JP4916012B2 - Fluid damper - Google Patents

Description

  The present invention relates to a fluid damper.

Fluid dampers are used in various fields, and Patent Documents 1 and 2 listed below include examples of such liquid dampers. The former is used for a folding table. When the top plate is rotated between the horizontal use position and the vertical storage position, a rotation resistance is applied so that an impact is not generated at each rotation end. In the latter, it is used for door closers, and when opening the door, the resistance is reduced and lightly opened, but when closing, devise to increase the resistance so that it does not close shockingly and close slowly, The closed end is devised so that it can be reliably closed by reducing the resistance. Moreover, the fluid damper by this applicant before improving to this invention is disclosed by the following patent document 3. FIG.
JP 2004-135725 A JP 2003-193740 A JP 2007-46729 A

However, the fluid damper can be operated in various resistance changes by various structures according to the purpose. For example, in a cabinet to which a fluid damper is applied, even if the drawn drawer is pushed in vigorously, if the fluid damper starts to operate near the end of the drawer's storage, the drawer will first absorb the excessively strong momentum of the drawer. If it can be prevented from hitting the casing well, and then the storage can be completed with a soft storage feeling, the cabinet has a higher-class feeling. As a fluid damper exhibiting such an action, there is a structure of the above-mentioned Patent Document 3. However, a fluid damper having a structure that can achieve a softer storage feeling than an alternative structure or a structure of Patent Document 3 is desired. It is also important to improve the fluid-tight reliability of the fluid-tight flexible sliding member 24 in Patent Document 3.
The problem to be solved by the present invention is to provide a fluid damper that satisfies the above-mentioned needs.

In the first invention, the operating shaft moves back and forth along the longitudinal direction of the casing in the casing of the casing filled with fluid, the indoor diameter dimension of the casing is constant along the longitudinal direction, A fixed-position member having a fixed-position member communication passage having an outer diameter having a gap with respect to the inner wall of the casing and penetrating from the front surface to the rear surface is provided at a fixed position at a rear portion of the operation shaft, The moving member has a moving member that moves back and forth on an operating shaft between a fixed position member and a predetermined position behind the moving member. The moving member has an outer peripheral portion facing the inner wall of the casing that is elastic in the radial direction. On the front surface of the movable member that slides in a fluid tight manner against the rear surface of the fixed-position member, a convex portion that has elasticity and can be crushed with a predetermined force or more is provided. Before being separated by the presence of the moving member A communication passage that communicates between the casing chamber and the rear casing chamber. When the convex portion is crushed and the front surface of the moving member contacts the rear surface of the fixed-position member, the fixed passage is provided. Except for the flow path in which the position member communication path and the communication path communicate with each other, the front casing chamber and the rear casing chamber can be in close contact with each other, and the casing rearward portion of the casing has the most operating shaft. An elastic block is disposed behind the moving member when positioned rearward, and the fluid in the casing can be compressed and restored by the pressure of the fluid without entering the inside of the elastic block . The front part of the casing is provided with a soft member sealing member that seals liquid leaking from the inside of the casing through the surface of the operating shaft to the outside, and the sealing member is inserted through the operating shaft. The hole wall of the insertion hole is provided with a plurality of annular convex portions having a mountain-shaped cross section projecting toward the central axis of the insertion hole at a plurality of positions in the front-rear direction, and the inner diameter of the annular convex portion is A sealing region in which the rear slope of the chevron cross-sectional shape is smaller than the outer diameter of the operating shaft and forms a larger inclination angle with respect to the central axis than the front slope, and the annular convex portion is provided The portion provides a fluid damper characterized in that its thickness can be made thinner than the thickness of the region where the annular convex portion is not provided, and can be deformed following slight movement of the operating shaft .

The casing of the present application is not limited to a cylinder and may have a rectangular cross section. Accordingly, the fixed position member and the moving member are not limited to a circular shape, and include a shape such as a rectangular shape. Similarly, it is expressed as a diameter, but it is also used to indicate the outer dimensions and inner dimensions of a rectangle other than a circle.
Having a gap includes, for example, a case in which a groove is provided on the inner wall of the casing, and fluid is communicated before and after the member through the groove.
The fluid-tight state is an air-tight state in the case of gas and a liquid-tight state in the case of liquid.
Examples of the porous elastic block include urethane foam. In order to prevent the fluid from entering the inside, the holes inside the elastic block are not in communication with each other so that most of the holes open to the surface of the elastic block.

  In the second invention, the moving member of the first invention is disposed on the side facing the fixed position member, and has an outer diameter dimension that slides in a fluid tight manner against the inner wall of the casing, A flexible member having a elasticity that is more flexible than the fixed-position member, and having a convex portion provided on the front surface thereof and having elasticity and capable of being crushed with a predetermined force or more, and the flexible member And a hard member that has an outer diameter that has a gap with respect to the inner wall of the casing and is less likely to be deformed than the flexible member. And the flexible member are provided so as to extend over the flexible member.

In the third invention, the moving member of the first invention is disposed on the side facing the fixed position member, and has an outer diameter dimension that slides in a fluid tight manner against the inner wall of the casing, It is a flexible plate having elasticity that is more flexible than the fixed position member, and has a convex portion that is provided on the front surface thereof and has elasticity and can be crushed with a predetermined force or more,
In the predetermined rear position, there is provided another fixed position member that is a hard member that has an outer diameter having a gap with respect to the inner wall of the casing and is harder to deform than the flexible member,
The other fixed position member is provided with another fixed position member communication path at a position where the flexible member can communicate with the communication path of the flexible member when the flexible member contacts the other fixed position member. Constitute.

In a fourth invention, the flexible member of the second or third invention is provided with an annular groove near the outer peripheral edge of the rear surface thereof, and further, a cone in which the outer peripheral surface of the flexible member is reduced in diameter in the front direction. It forms so that it may form.
According to the fifth aspect of the invention, there is provided an urging means for urging the operating shaft of the first to fourth aspects of the invention in the rear side direction or the front side direction.

In the first invention, when the operation shaft starts to move backward from the position where the operation shaft is most drawn out (front position), the moving member receives the resistance force of the fluid in the rear casing chamber and is located at the rear position of the operation shaft. Pressed against a fixed position member. At this time, when the speed of the operating shaft is higher than the predetermined value, that is, when the pressing force is higher than the predetermined force, the convex portion is sufficiently crushed, and in this state, the communication path and the fixed position member communication path are merely communicated. Since there is no other flow path, the greatest fluid resistance force is exhibited and the approaching force of the operating shaft is suppressed. However, since an elastic block is disposed in the rear part of the casing, which is the direction in which the operating shaft enters, the pressure corresponding to the largest fluid resistance force acts on the elastic block and is elastic. The block is compressed and deformed in the direction of decreasing the thickness. By this deformation, the operating shaft enters while the fluid resistance is gradually reduced to a soft feeling. As a result, the collapsed convex part is restored by its elasticity, and a gap according to the restoration height of the convex part is created between the fixed position member and the moving member, so a new flow path is secured through this gap. Therefore, the fluid resistance is reduced by that amount, and the operating shaft can enter with a light force. By the compression deformation of the elastic block and the generation of a new flow path, the operating shaft can reach the end while entering a soft feeling.
In addition, due to the movement of the working shaft, the volume of the fluid in the casing needs to fluctuate due to the volume fluctuation of the working shaft in the casing. However, especially when the fluid is liquid, the volume fluctuation is difficult. The elastic block absorbs.
When the elastic block is porous, it compresses and deforms in the direction in which the thickness of the elastic block is reduced with the elasticity of the elastic block material itself while compressing the internal porosity by the pressure of the fluid. This deformation gradually reduces the fluid resistance to a softer feeling.
Moreover, since the rear side slope of the mountain-shaped cross section of the annular convex portion has a larger inclination angle than the front side slope, it becomes easy to handle the liquid adhering to the surface when the operating shaft is drawn forward. Still, the liquid remaining on the surface of the operating shaft that has not been handled and remains on the surface of the operating shaft again, when the operating shaft enters the casing again, the inclination angle of the front slope of the annular convex portion is relatively small. It is difficult to handle and the rate of returning to the casing increases. Since a plurality of such annular protrusions are provided, the sealing effect is further enhanced. Furthermore, the operating shaft is inserted into the opening provided in the casing. However, since the operating shaft moves forward and backward, it is inevitable that a slight gap is provided between the opening and the operating shaft. Therefore, when the operating shaft moves back and forth, a slight lateral vibration corresponding to the gap occurs. However, the seal region of the seal member of the present application is configured so that the thickness thereof is thinner than the thickness of the region where the annular convex portion is not provided, and can follow the above-described lateral vibration, and thus a plurality of annular convex portions. The sealing effect can be maintained.

  When the operation shaft starts to move backward from the position where the operation shaft is most pulled out, the moving member is pressed against the fixed position member. If the speed of the operation shaft at this time is lower than a predetermined value, that is, the pressing force is reduced. If the force is less than the predetermined force, the crushed state of the convex portion becomes incomplete, and there is a gap between the facing surfaces of the fixed position member and the moving member in addition to the communication flow path between the moving path of the moving member and the fixed position member communicating path. Therefore, there is also a flow path passing through this gap, and the operating shaft can reach the end while entering with a soft feeling.

  If the operating shaft is to be pulled forward from the approach end position, the moving member receives the resistance of the fluid in the front casing chamber and is pushed to a predetermined position behind the home position member. Therefore, in addition to the flow path in which the communication path of the moving member and the fixed position member communication path communicate with each other, the gap between the outer periphery of the fixed position member and the inner wall of the casing passes through the gap between the facing surfaces of the fixed position member and the moving member. Since the flow path passing through the gap is added as a flow path communicating with the communication path of the moving member, the fluid resistance is reduced. In this case, since the gap is larger than the gap between the facing surfaces of the fixed position member and the moving member in the case where the above-mentioned convex portion is not completely crushed, the fluid resistance is the smallest, and the operation shaft is drawn out smoothly. To be done.

  In 2nd invention, the form of the moving member is prescribed | regulated, it has a plate-shaped flexible member and a hard member, and it is set as the form which positions a flexible member between a hard fixed-position member and the said hard member. . As a result, even if the flexible member deviates to any of the front and rear sides according to the forward / backward movement direction of the operating shaft, it is held by the harder member, its shape is maintained, and the fluid tightness is maintained.

  In the third invention, the moving member is constituted by a flexible member, and another fixed position member which is a hard member is provided at a predetermined rear position described in the first invention. As a result, even if the flexible member moves to any side in accordance with the advancing / retreating movement direction of the operating shaft, the flexible member is held by the harder member, its shape is maintained, and the fluid tightness is maintained.

  In the fourth invention, the outer peripheral edge near the annular groove is easily deformed by the interaction between the annular groove and the conical outer peripheral surface. Accordingly, if the outer peripheral edge is set to a flexible member having a size to press against the inner wall of the casing, the fluid tightness can be effectively maintained.

In one aspect of the fifth aspect of the invention, since the operating shaft is biased in the approach end position direction (rear side direction), the operation shaft normally stands by at the approach end position.
In another aspect, since the operating shaft is biased in the approach start position direction (front side direction), the operation shaft normally stands by at the approach start position. Even if the object is not inadvertently connected to the operating shaft, when the object is carelessly stored and moved, the operating shaft receives the object and the momentum can be reduced by the action of the fluid damper.

  FIG. 1 is a plan view of a liquid damper having a fluid damper similar to the piston / cylinder mechanism according to the present invention in a partially omitted cross-sectional view, and FIG. 4 is an enlarged view of a main part thereof. There is a portion in which the operating shaft is depicted in a see-through state, and the same applies to FIGS. 2 and 3 described later. The casing 10 corresponding to the cylinder in this case has a rectangular cross section as shown by a two-dot chain line in FIG. 7 along the arrow GG, and the inner diameter of the casing defining the inner wall surface 10A is the operating shaft. Constant regardless of the longitudinal position within the 12 operating ranges. The inner wall cross-sectional shape of the casing 10 is a shape in which a rectangular corner is rounded and a slight curvature is provided on each side of the rectangle as shown in FIG. 7 (this shape is also called a rectangular shape). The reason for rounding is to prevent the casing from being damaged by stress concentration on the corners due to the internal oil pressure.

  An operating shaft 12 is inserted into the casing 10 and is configured to be capable of entering backward and moving backward. The member 18 is a sealing member for sealing. A fixed position member 22 made of a rectangular plate member is held at a fixed position at a predetermined position in the rear part of the operating shaft 12 and is sandwiched by a member 12B such as an E-ring. Its outer diameter is smaller than the casing inner diameter and creates a gap with respect to the wall surface 10A. The fixed position member 22 can be formed of a synthetic resin material or metal that has a normal hardness and can be used as a structural material, such as polyacetal. A moving member 23 that is movable at a predetermined position behind the member 22 and on the operating shaft between the rear end large diameter portion 12A of the operating shaft is disposed. In this example, the moving member 23 is composed of two rectangular plate-like members 24 and 26.

  The plate-like flexible member 24 is formed of a flexible material (soft material) that is elastic and deformable in the radial direction so as to be slidable while being in liquid-tight contact with the casing inner wall 10A. When oil is used as the fluid in the casing, it is made of, for example, oil resistant rubber. In particular, a thermoplastic type polyurethane resin (TPU) and other polyurethane resins (PU) using the same injection molding method as the thermoplastic resin are preferable. In terms of hardness, JIS A in the range of 70 to 100 degrees is appropriate. The outer diameter is set to a dimension that allows the liquid to slide in a liquid-tight manner with no gap with respect to the inner wall of the casing. Accordingly, the entire circumference of the rectangular shape is brought into close contact.

  Therefore, the flexible member 24 is provided with an annular groove 24M whose annular state is shown in FIG. 7 in addition to the one shown in FIGS. Further, as clearly shown in FIG. 4 and the like, the outer peripheral surface 24S of the member 24 is formed in a conical shape whose diameter is reduced in the forward direction. Due to the interaction between the annular groove 24M and the conical outer peripheral surface 24S, the outer peripheral edge near the annular groove is easily deformed. Therefore, if the outer diameter of the member 24 is appropriately larger than the inner diameter of the casing inner wall 10A, the liquid-tight state can be effectively maintained.

  Furthermore, an annular convex portion 24T having an appropriate thickness and height is formed on the front surface of the member 24, that is, the surface facing the member 22. The convex portion is crushed when pressed against the member 22 or the E-ring 12B integral with the member 22 with a force of a predetermined level or more.

  On the other hand, the plate-like hard member 26 can be formed of the same structural material as the fixed position member 22. Further, the outer diameter is smaller than the inner wall of the casing, and the gap is formed. In this example, the two members 24 and 26 are not integrated but separated, and the flexible member 24 is disposed between the hard member 26 and the fixed position member 22. A communication path is formed between the casing chamber A on the left side of the member 26 and the casing chamber B on the right side of the member 22 so as to allow oil in each chamber to pass therethrough. The member 22 is provided with a fixed position member communication path 22H, the member 24 is provided with a communication path 24H, and the member 26 is provided with an appropriate number of communication paths 26H, for example, two. The communication paths of the members 24 and 26 are circular straight paths having the same diameter in cross section, and those of the member 22 are circular sections but circular. The diameter is reduced toward the right chamber B.

  In this example, since it is a rectangular casing, the members 22, 24, and 26 do not rotate around the operating shaft, so that the communication paths are always in corresponding positions. When the casing is a cylinder, it is necessary to devise a way to stop the rotation so that each member does not rotate relative to the key, for example, so as to slide on the key. The members 24 and 26 may be integrated by bonding or the like. However, the member 26 may be configured as another fixed-position member that does not move on the operating shaft but is held at a fixed position pressed against the rear end large-diameter portion 12A, and only the member 24 may be movable. As another form example, a flexible member made of the same flexible material as that of the member 24 of the present example is fixed and held so as to fill a gap with the inner wall of the casing on the outer periphery of the movable member 26. The convex portion 24T may be provided on the front surface of the member 26.

In this example, the coil spring 20 is provided so as to allow the operating shaft to be inserted in order to use an automatic pull-in mechanism, which will be described later, and has a biasing force that biases the operating shaft toward the approach end position.
FIG. 1 is a diagram in which the operating shaft is going to be pulled out from the approach end position, FIG. 2 is a diagram of an initial state in which the operating shaft is entered at a speed (predetermined force) from a position where the operating shaft is most pulled out, and FIG. FIG. 3 shows a state diagram after the state of FIG. 4 to 6 are enlarged views of main parts corresponding to FIGS. 1 to 3, respectively.

  First, as shown in FIG. 2, a description will be given of a state in which the operating shaft 12 is approaching from the position where the operating shaft 12 is sufficiently pulled out in the approach end position direction (left direction in FIG. 2). Since the operating shaft 12 moves to the left, the moving member 23 receives the resistance of the oil and is biased toward the fixed position member 22. In this case, when the approach speed of the operating shaft is higher than a predetermined value, the fluid resistance (oil resistance) received by the oil in the left chamber A is increased by a predetermined value or more, and the aforementioned annular convex portion 24T is in this case the end face of the E ring 12B. The front surface of the member 24 and the rear surface of the member 22 are brought into contact and close contact with each other. Then, as shown in FIG. 5, the oil in the left side chamber A flows toward the right side chamber B only through the flow path in which the communication path 26H, the communication path 24H, and the fixed position member communication path 22H communicate with each other. At this time, it is designed to exhibit a large oil resistance. Therefore, the approach speed of the operating shaft that is faster than a predetermined value is immediately reduced.

  However, the porous elastic block 16 is disposed behind the moving member 23 in the indoor rear portion of the casing 10 when the operating shaft 12 is located at the rearmost (inside) position. Here, the casing 10 is disposed at the rearmost part of the room. As an arrangement method, it is included in a plastic case 14. Appropriate holes are provided in the front side wall of the case 14, and oil pressure acts on the elastic block 16. The elastic block 16 is porous such as foamed urethane, and the oil in the casing does not enter the inside of the elastic block, and soft compression and restoration are possible while crushing the pores by the pressure. Since many of the internal pores exist independently without being connected to each other, the oil does not enter the interior.

  An oil pressure corresponding to a large oil resistance acts on the elastic block 16 when the approach speed of the operating shaft that is faster than a predetermined speed in the previous operation is immediately reduced. Thereby, the elastic block is compressed and thinned. In addition, since the approach speed of the operating shaft is reduced, the oil resistance is reduced, and the fact that the annular convex portion 24T of the member 24 has been crushed is restored, and accordingly, the front surface of the member 24 and the rear surface of the member 22 are restored. A gap is formed between the two. This state is shown in FIGS. That is, as shown in FIG. 6, in addition to the flow path in which the communication path 26H, the communication path 24H, and the fixed position member communication path 22H in the case of FIG. A flow path indicated by an arrow is generated. Due to the increase of the flow path and the thin deformation of the elastic block due to the oil pressure, the soft approach is entered immediately after the approach speed is reduced.

  Further, in the case where the operating shaft 12 is advanced from the position where the operating shaft 12 is pulled forward toward the approach end position, if the operating speed of the operating shaft is slower than a predetermined speed, the state shown in FIG. enter in.

  Returning to FIG. 1, when the operating shaft is pulled out from the approach end position, the moving member 23 is pressed against the rear end large diameter portion 12 </ b> A by oil resistance. Although clearly shown in FIG. 4, in addition to the flow paths that pass through the communication paths, a flow path that passes between the outer periphery of the member 22 and the casing inner wall 10 </ b> A, and between the rear surface of the member 22 and the front surface of the member 24. Becomes the largest and the oil resistance becomes very small. Further, the coil spring 20 is pulled out from the state where the resistance force is the smallest.

  The oil resistance increases in the order of FIG. 1, FIG. 3, and FIG. Therefore, when the head 12H of the operating shaft 12 protruding from the casing is attached to, for example, the automatic drawing device for the drawer provided in the cabinet described in FIG. Even if it is lightly pulled out and stowed, even if it is stowed vigorously, when the automatic retracting device starts to operate (FIG. 2), the oil resistance exhibits the strongest resistance, but the soft block 16 is compressed with the compression action. After that, the momentum is relaxed, and after that (FIG. 3), the strong oil resistance is reduced, so that it can be stored by the automatic pull-in force by the biasing force of the coil spring 20.

  FIG. 8 is a diagram illustrating an example of an automatic retracting device. For example, it is an apparatus using a slide member 34 having a concave portion 34A in which a convex portion 32 provided on a cabinet drawer can be engaged. For example, the rail member 30 having the same width as the casing 10 is disposed between one wall surface 30A and the other wall surface 30B and can slide in the longitudinal direction. The head 12H of the operating shaft 12 of the liquid damper is engaged with the casing side end of the slide member so as to be rotatable so as to enable the inclination described later, and the operating shaft advances and retreats following the longitudinal movement of the slide member. To do. An engagement hole or engagement recess 30 </ b> H is formed at an appropriate position on the other wall surface 30 </ b> B of the rail member 30. On the other hand, the engaging projection 34B is provided on the slide member 34 on the side facing the wall surface 30B.

  Further, the point of action of the tensile force applied to the slide member 34 received from the convex portion 32 engaged with the concave portion 34A is located at a position deviated from the central axis of the operating shaft 12 toward the wall surface 30A. As a result of the drawer movement in the right direction (drawer opening direction), a moment M is generated in the slide member 34 in the clockwise direction in the drawing. Therefore, the engaging projection 34B always presses the wall surface 30B while the slide member is moving in the right direction. When the sliding member reaches the engaging hole 30H, the engaging protrusion 34B enters and engages with the engaging hole 30H. As a result, the slide member tilts as shown by 34 ', and the convex portion 32 moves to the right until the engagement with the concave portion 34A is released and the drawer is fully pulled out with the slide member remaining at the position of the engagement hole. (Denoted by 32 ').

  When the slide member is at the position indicated by 34 ′, the operating shaft 12 is at the position where it is most pulled out from the casing 10. Further, the coil spring 20 is most compressed. Thereafter, when the drawer is housed, the drawer is pushed in by a human hand. When the convex portion 32 presses the pushing end side wall surface (the left side wall surface in FIG. 8) of the concave portion 34A, the slide member is illustrated in FIG. As a result, a counterclockwise moment is generated, and the engagement between the engagement protrusion 34B and the engagement hole 30H is released. Thereafter, even if the person does not push in the drawer, it is automatically pulled in by the biasing force of the coil spring described above. In the final position where the drawer is drawn, the slide member 34 is the position shown on the left side of FIG. 8, and the operating shaft is at the entry end position.

  In the above mechanism, the biasing force of the coil spring 20 is minimum at the beginning of drawing out the drawer, and the oil resistance increases in the order shown in FIGS. 1, 3, and 2, so that it can be pulled out lightest. In this case, when the automatic pull-in mechanism starts to operate, the state shown in FIG. 2 is reached, so that the oil resistance is the highest, and the drawer with the momentum is moved. Serves buffering action. At this time, since the action of the elastic block 16 is added, a buffering action can be achieved with a soft feel, and thereafter, the state shown in FIG. 3 is obtained, and the oil resistance can be reduced and the automatic pulling force of the coil spring 20 can be utilized.

  The automatic pull-in mechanism may have another form and is not limited to the form shown in FIG. Further, although the fixed position member communication path 22H provided in the member 22 has a conical shape, it may have a cylindrical shape. When the operating shaft 12 is made to enter (FIGS. 2 and 3), the oil resistance is increased, and when the operating shaft 12 is moved backward (FIG. 1), it is desired to make it as small as possible. Further, the casing is not rectangular, but a cylindrical or other shape casing may be used.

  As described above, as an application form of the liquid damper and the gas damper, if the operating shaft 12 is urged by the urging means in the direction in which the operating shaft 12 protrudes from the casing 10 (the pulling direction), an object such as a drawer is connected to the urging means. Even if it does not make it, the buffering action of the accommodation movement of an object can be fulfilled.

  FIG. 9 is an enlarged view of the vicinity of the seal member 18 that prevents leakage of oil in the casing when the operating shaft 12 that is a cylinder or a column moves forward and backward with respect to the casing 10. This member is formed of the same material as that described for the flexible member 24, that is, a flexible material (soft material) having elasticity and being deformable. For example, it is made of oil resistant rubber. In particular, a thermoplastic type polyurethane resin (TPU) and other polyurethane resins (PU) using the same injection molding method as the thermoplastic resin are preferable. When expressed in terms of hardness, those in the range of JIS A 70 degrees to 100 degrees are appropriate.

  The annular seal member 18 is provided with an annular insertion hole 18H having an inner diameter larger than the outer diameter of the operation shaft through which the operation shaft is inserted. The hole wall of the insertion hole protrudes toward the center side. Two annular convex portions 18A and 18B having a chevron cross-sectional shape are arranged in the front-rear direction. The inner diameters of these annular projections are smaller than the outer diameter of the operating shaft. Further, the rear slope K1 which is the casing chamber side forms a larger inclination angle with respect to the central axis than the front slope K2. As an example, the former angle θ1 is 70 degrees and the latter angle θ2 is 30 degrees. When the operating shaft 12 is drawn forward, it becomes easy to handle oil adhering to the surface of the operating shaft by the action of the rear inclined surface K1 with a large inclination angle. Still, the oil remaining on the surface of the operating shaft without being handled is less likely to be handled because the tilt angle of the rear slope K2 is relatively small when the operating shaft next enters the casing. The rate of going back into the casing increases. Moreover, since two such annular convex portions are provided, the sealing effect is further enhanced.

  The operating shaft 12 passes through the opening 10H having a circular cross section provided in the casing 10, but moves forward and backward in the front-rear direction, so that a slight gap Δ is inevitable between the opening and the operating shaft. . Therefore, when the operating shaft moves forward and backward, a slight lateral vibration corresponding to the gap occurs. However, the sealing member 18 of the present application is provided with the annular groove 18M on the end face on the casing chamber side, so that the thickness of the seal region 18J provided with the annular protrusions 18A and 18B is provided with the annular protrusion. Since the seal region 18J provided with the annular convex portion can follow the above-mentioned lateral vibration, the sealing effect by the annular convex portions 18A and 18B is maintained. The

  The seal member 18 in the above example is provided with an annular groove 18M so that the seal region 18J has a predetermined flexibility. This annular groove presses the seal holding member 19 against the end surface of the outer region 18K. This is necessary because a structure for holding the seal member is employed. However, if the holding means for the seal member 18 is changed, the annular groove 18M is not necessary. For example, the outer region 18K can be eliminated by showing the outer shape of the seal member by a two-dot chain line 18L. . The annular protrusions 18C and 18D on the outer periphery of the seal member 18 have a mountain shape in cross section. The seals prevent pressure leakage and holding of the casing 10 in the circular mounting hole 10H 'and oil leakage from the outer periphery of the seal member. It is an elastic pressing part for.

  INDUSTRIAL APPLICABILITY The present invention can be used for furniture and doors having double doors, sliding doors, drawers, and the like.

FIG. 1 is a plan view with a partially omitted cross section of the overall structure of a liquid damper according to the present invention. FIG. 2 is a plan view of an initial state in which the operating shaft is made to enter at a predetermined speed or more from the position where the operating shaft is most pulled out. FIG. 3 is a plan view showing a state after the state of FIG. FIG. 4 is an enlarged view of a main part corresponding to FIG. FIG. 5 is an enlarged view of a main part corresponding to FIG. FIG. 6 is an enlarged view of a main part corresponding to FIG. FIG. 7 is a diagram of the flexible member and the casing taken along line GG in FIG. FIG. 8 is an illustration of an automatic retracting device. FIG. 9 is an enlarged view of the vicinity of the seal member.

DESCRIPTION OF SYMBOLS 10 Casing 12 Actuating shaft 18 Annular seal member 22 Fixed position member 22H Fixed position member communication path 23 Moving member 24 Flexible member 24H Communication path 24M Annular groove 24T Annular convex 26 Hard member 26H Communication path

Claims (5)

The operating shaft (12) moves back and forth along the longitudinal direction of the casing in the casing (10) filled with fluid,
The indoor diameter dimension of the casing is constant along the longitudinal direction,
A fixed position member communication path (22H) having an outer diameter dimension having a gap with respect to the inner wall (10A) of the casing at a fixed position at the rear portion of the operating shaft and penetrating from the front surface to the rear surface. A position member (22) is provided;
A moving member (23) that moves back and forth on the operating shaft between the fixed position member and a predetermined position behind the fixed position member;
The moving member is
The outer peripheral part facing the inner wall of the casing has elasticity in the radial direction and slides in a fluid-tight manner against the inner wall of the casing, and the elasticity is applied to the front surface of the moving member facing the rear surface of the fixed position member. And has a convex portion (24T) that can be crushed with a predetermined force or more,
There are provided communication passages (24H, 26H) for communicating the front casing chamber (B) and the rear casing chamber (A) separated by the presence of the moving member,
When the convex portion is crushed and the front surface of the moving member comes into contact with the rear surface of the fixed position member, the casing chamber on the front side except the flow path where the fixed position member communication path communicates with the communication path And close contact with the rear casing chamber is possible,
An elastic block (16) is disposed behind the moving member when the operating shaft is located at the rearmost position in the interior of the casing, and the fluid in the casing is placed inside the elastic block. Can be compressed and restored by the pressure of the fluid without entering the
The front part of the casing is provided with a sealing member (18) of a soft member that seals liquid leaking outside from the inside of the casing through the surface of the operating shaft,
The seal member is provided with an insertion hole (18H) through which the operating shaft is inserted,
The hole wall of the insertion hole is provided with a plurality of annular convex portions (18A, 18B) having a mountain-shaped cross-section projecting toward the central axis of the insertion hole at a plurality of positions in the front-rear direction.
The inner diameter of the annular convex portion is smaller than the outer diameter of the operating shaft,
The rear slope (K1) of the mountain-shaped cross section forms a larger inclination angle with respect to the central axis than the front slope (K2),
The seal region portion (18J) provided with the annular convex portion can be deformed following the slight deflection of the operating shaft by making its thickness thinner than the thickness of the region where the annular convex portion is not provided. Features fluid damper.   The moving member (23) is disposed on the side facing the fixed position member (22) and has an outer diameter dimension that slides in a fluid tight manner against the inner wall (10A) of the casing. A flexible member (24) which is a plate having elasticity more flexible than the position member, and has a convex portion (24T) which is provided on the front surface and has elasticity and can be crushed by a force of a predetermined level or more; A hard member (26) which is disposed at a position sandwiching the flexible member with the fixed position member, has an outer diameter having a gap with respect to the inner wall of the casing, and is less deformable than the flexible member; The fluid damper according to claim 1, wherein the communication path is provided between the hard member and the flexible member. The moving member is disposed on the side facing the fixed-position member, has an outer diameter dimension that slides in a fluid-tight manner against the inner wall of the casing, and is more flexible than the fixed-position member. It is a flexible member having a convex portion that is provided on the front surface and has elasticity and can be crushed with a predetermined force or more.
In the predetermined rear position, there is provided another fixed position member that is a hard member that has an outer diameter having a gap with respect to the inner wall of the casing and is harder to deform than the flexible member,
The other fixed position member is provided with another fixed position member communication path at a location where the flexible member can communicate with the communication path of the flexible member when the flexible member contacts the other fixed position member. Item 2. The fluid damper according to Item 1.   The said flexible member is provided with the annular groove (24M) near the outer periphery of the rear surface, Furthermore, the outer peripheral surface (24S) of this flexible member is formed in the cone shape diameter-reduced to the front side direction. The fluid damper according to 2 or 3.   The fluid damper according to any one of claims 1 to 4, further comprising a biasing means (20) for biasing the operating shaft in a rearward direction or a forward direction.

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