JP6644526B2 - Buffer device and strut using the same - Google Patents

Description

  The present invention relates to a shock-absorbing device provided on an inner member that can be inserted into and removed from an outer cylinder, which can be brought into close contact with the inner peripheral surface of the outer cylinder when the inner member is inserted into the outer cylinder and slidable, and a column using the same.

  Conventionally, an Irrigator stand that suspends a drip bottle includes an outer cylinder, an inner member that can be inserted into and removed from the outer cylinder, and fixing means such as a screw for fixing a relative position between the outer cylinder and the inner member, What can adjust a support height is known.

  In this type of irrigator stand, if the fixing by the fixing means is not enough, or if the user accidentally releases his hand while releasing the fixing and adjusting the support height, There is a possibility that the upper member of the outer cylinder and the inner member may fall suddenly.

  As a device for preventing such a sudden drop, a shock absorber provided at an end of an insertion portion of an inner member is known (for example, see Patent Document 1). In the shock absorber, the internal space of the outer cylinder is made substantially closed to increase the pressure of the internal space, and the air velocity causes the falling speed of the upper member of the outer cylinder and the inner member to fall (ie, (Moving speed in a direction to narrow the internal space).

JP 2013-103013 A

  However, the shock absorber described in Patent Literature 1 has high airtightness, so that the pressure in the internal space of the outer cylinder does not easily change. Therefore, when changing the relative position between the outer cylinder and the inner member, there is a problem that a large force is required due to air resistance.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a shock absorber that easily changes a relative position between an outer cylinder and an inner member and a column using the same.

  In order to achieve the above object, a shock absorber according to the present invention is provided on an inner member that can be inserted into and removed from an outer cylinder, and when the inner member is inserted into the outer cylinder, the shock absorber comes into close contact with the inner peripheral surface of the outer cylinder. A movable shock absorber, a communication path for communicating the internal space of the outer cylinder with the outside, a communication hole having a smaller diameter than the communication path, and when the inner member is inserted into the outer cylinder, And a flow regulating means for closing the opening of the communication passage, allowing the fluid to flow through the communication hole, and opening the opening when the inner member is pulled out from the outer cylinder. And

  As described above, in the shock absorber of the present invention, the opening is opened by the flow rate adjusting means when the inner member is pulled out from the outer cylinder. As a result, the fluid easily flows into the internal space, so that the inner member can be easily pulled out of the outer cylinder with a small force.

  On the other hand, at the time of the insertion operation of the inner member into the outer cylinder, the communication passage is closed by the flow rate adjusting means but is not completely closed, and the outside and the inner space of the outer cylinder are communicated via the communication hole. State. Therefore, the fluid inside the inner space of the outer cylinder is discharged to the outside through the communication hole having a smaller diameter than the communication passage. As a result, the resistance at the time of the insertion operation of the inner member into the outer cylinder is larger than the resistance at the time of the withdrawal operation, but smaller than the resistance of the conventional shock absorber in which the fluid is not discharged.

  Therefore, according to the shock absorber of the present invention, the relative position between the outer cylinder and the inner member can be easily changed.

  Further, in the shock absorber according to the present invention, the flow rate adjusting means is located at a position covering the opening when the outer cylinder and the inner member are fixed and when the inner member is inserted into the outer cylinder. When the opening is closed and the inner member is pulled out from the outer cylinder, the inner member is pushed away from the opening by a force received from a fluid flowing from the outside into the internal space through the communication path. Thus, the opening may be opened.

  Further, in the shock absorber according to the present invention, the flow rate adjusting means is located at a position distant from the opening when the outer cylinder is fixed to the inner member and when the inner member is pulled out from the outer cylinder. Opening the opening, and covering the opening by a force received from a fluid that is going to flow out of the internal space through the communication path to the outside during the operation of inserting the inner member into the outer cylinder. The opening may be closed by being pushed in the direction.

  In the shock absorber according to the present invention, the flow rate adjusting means is a flexible valve body that covers the opening, and the valve body flows into the internal space from the outside through the communication passage. You may comprise so that it may bend by the force received from a fluid.

  In addition, the flow rate adjusting unit includes a valve element that covers the opening, and an urging member that urges the valve element to press the valve element against the opening, and the valve element is provided through the communication passage. You may comprise so that it may move by the force received from the fluid which flows into the said internal space from the said outside.

  In the shock absorber of the present invention, it is preferable that the communication hole is formed in the valve body.

  Since the valve body is a plate material, a process of forming the communication hole can be easily performed, and the diameter of the communication hole can be accurately set to an arbitrary size. That is, when the communication hole is provided in the valve body, it is possible to easily manufacture a member that can obtain a desired air discharge amount. Therefore, for example, when the inner member and the outer cylinder are arranged vertically, the upper member of the outer cylinder and the inner member may be configured to drop slowly at an arbitrary speed.

  Further, in order to achieve the above object, the support of the present invention may be configured by the above-described shock absorber, an outer cylinder, and an inner member.

FIG. 1 is a perspective view showing an external view of an irrigator stand provided with a shock absorber according to a first embodiment of the present invention. FIG. 2 is a perspective view of a shock-absorbing device provided in the Irrigator stand of FIG. 1. FIG. 3A is a cross-sectional view taken along line AA of the shock absorber of FIG. 2, FIG. 3A shows a state at the time of insertion, and FIG. The perspective view of the shock absorber concerning a 2nd embodiment of the present invention. FIG. 5B is a sectional view of the shock absorber of FIG. 4 taken along the line BB, FIG. 5A shows a state at the time of insertion, and FIG. The perspective view of the buffer device concerning a 3rd embodiment of the present invention. 7A is a cross-sectional view of the shock absorber of FIG. 6, and FIG. 7A shows a state at the time of insertion, and FIG. 7B shows a state at the time of pull-out. The perspective view of the buffer device concerning a 4th embodiment of the present invention. 9 is a cross-sectional view of the shock absorber of FIG. 8 taken along the line DD. FIG. 9A shows a state at the time of insertion, and FIG. 9B shows a state at the time of pull-out. The perspective view of the shock absorber concerning the modification of a 4th embodiment of the present invention. FIG. 14 is a perspective view of a shock absorber according to another modified example of the fourth embodiment of the present invention. The perspective view of the buffer device concerning a 5th embodiment of the present invention. FIG. 13 is a plan view showing a damper part of the shock absorber of FIG. 12. FIG. 14B is a cross-sectional view taken along the line EE of the shock absorber of FIG. 12, wherein FIG. 14A shows a state at the time of insertion, and FIG. It is a schematic diagram of the shock absorber concerning 6th Embodiment of this invention, FIG. 15: A is a front view, FIG. 15: B is a rear view. FIG. 16 is a perspective view showing a shape of a damper part of the shock absorber of FIG. 15. 17A is a cross-sectional view of the shock absorber of FIG. 15 in a direction along the axis, FIG. 17A shows a state at the time of insertion, and FIG. 17B shows a state at the time of pulling out. FIG. 18A is a cross-sectional view of the shock absorber of FIG. 17 taken along the line FF. FIG. 18A shows a state at the time of insertion, and FIG.

[First Embodiment]
Hereinafter, an irrigator stand provided with a shock absorber according to the first embodiment will be described with reference to FIGS. In FIG. 3, a thick arrow indicates a moving direction of a support pipe or a shock absorber, and a thin arrow indicates a flow of air.

  First, the configuration of the irrigator stand S will be described with reference to FIGS.

  As shown in FIG. 1, the irrigator stand S (post) includes a base 1, six legs 2 extending radially from the base 1, casters 3 attached to the lower ends of the legs 2, and a base. 1, a cylindrical support pipe 4 (outer cylinder), a cylindrical upper pipe 5 (inner member) inserted into the support pipe 4, and an upper pipe 5 opposite to the support pipe 4 side. A hanging tool 6 attached to the end for hanging a drip bottle, etc .; a fixed handle 7 provided at an end on the upper pipe 5 side of the support pipe 4; And a handle 8 to be gripped by the user when moving S.

  The cylindrical support pipe 4 is provided below the upper pipe 5 therein, the wall surface of the support pipe 4, the base 1 for closing the lower end of the support pipe 4, and the end on the insertion side of the upper pipe 5 (that is, described later). The internal space 4a is hermetically sealed with the shock absorber 9A) (see FIG. 3).

  The cylindrical upper pipe 5 can be freely inserted into and removed from the cylindrical support pipe 4, and their relative positions can be arbitrarily changed when the fixed handle 7 is not used. An upper pipe-side fixing hole 5a penetrating the wall surface is formed at the tip of the upper pipe 5 (see FIG. 3).

  The fixed handle 7 includes a grip portion to be gripped by a user, and a male screw portion fixed to the grip portion. The male screw portion is screwed into a fixing hole (not shown) formed to penetrate the wall surface of the support pipe 4.

  When the fixed handle 7 is turned to one side, the tip of the male screw portion is pressed against the outer peripheral surface of the upper pipe 5 inserted into the support pipe 4, and the relative position between the support pipe 4 and the upper pipe 5 is fixed. . When the fixed handle 7 is turned to the other side, the fixing is released, and the relative position between the support pipe 4 and the upper pipe 5 can be changed.

  As shown in FIG. 2, a shock absorber 9 </ b> A is provided at an end of the upper stage pipe 5 on the insertion side of the support pipe 4.

  As shown in FIG. 3, the shock absorber 9 </ b> A includes an insertion portion 9 a inserted into the upper pipe 5 when attached to an end of the cylindrical upper pipe 5, and a sealing portion located outside the upper pipe 5. 9b.

  The insertion portion 9 a is formed to have a smaller diameter than the upper pipe 5. The insertion portion 9a has a shock-absorbing device-side fixing hole 9a1 formed so as to be oriented in a direction crossing the axis of the upper pipe 5 when the insertion pipe 9 is attached to the upper pipe 5. The shock absorber 9A and the upper pipe 5 are fixed by screwing a fixing screw 10 into the shock absorber side fixing hole 9a1 so as to penetrate the upper pipe side fixing hole 5a of the upper pipe 5.

  The sealing portion 9 b has a larger diameter than the upper pipe 5 and a smaller diameter than the support pipe 4. An annular recess 9b1 is formed on the outer peripheral surface of the sealing portion 9b. An O-ring 9c made of rubber is fitted into the annular recess 9b1 as a sealing member. When the upper pipe 5 is inserted into the support pipe 4, the O-ring 9 c comes into close contact with the inner peripheral surface of the support pipe 4 and is slidable. The O-ring 9c prevents the flow of air between the internal space 4a of the support pipe 4 existing below the shock absorber 9A and the outside of the irrigator stand S.

  When the insertion portion 9a is fixed after being inserted into the upper pipe 5, the upper end of the sealing portion 9b and the lower end of the upper pipe 5 abut. At this time, a part of the upper end of the sealing portion 9b is recessed so as to communicate with a communication passage 9d described later. Therefore, a gap communicating with the communication passage 9 d is formed between a part of the upper end of the sealing portion 9 b and the lower end of the upper pipe 5.

  A communication passage 9d penetrating the sealing portion 9b is formed in the shock absorber 9A. When the upper pipe 5 is inserted into the support pipe 4, the internal space 4 a of the support pipe 4 existing below the shock absorber 9 </ b> A and the outside of the irrigator stand S communicate with the communication path 9 d and the upper end of the sealing portion 9 b. Air (fluid) is communicablely communicated through a gap between the portion and the lower end of the upper pipe 5 and between the support pipe 4 and the upper pipe 5.

  The communication path is not limited to such a path, and may be any path that allows the internal space 4a to communicate with the outside of the Irrigator stand S via the communication path 9d.

  In the shock absorber 9A, the opening 9d1 of the communication passage 9d on the side of the internal space 4a is formed at the lower end of the sealing portion 9b.

  The opening 9d1 is covered by a flexible plate-shaped valve element 9e (flow rate adjusting means). The valve element 9e is attached to the lower end of the sealing portion 9b with one attachment screw 9f. That is, the valve element 9e has a cantilever shape in which the free end on one side in the longitudinal direction covers the opening 9d1 and the other side is fixed to the sealing portion 9b with the mounting screw 9f. Therefore, the opening 9d1 is closed by the valve 9e when the support pipe 4 and the upper pipe 5 are fixed, and is opened when the valve 9e is bent.

  The valve body 9e has a communication hole 9e1 for communicating the internal space 4a with the communication passage 9d in a state where the valve body 9e covers the opening 9d1. The diameter of the communication hole 9e1 is smaller than the diameter of the communication passage 9d.

  Next, with reference to FIG. 3, the function of the shock absorber 9A when changing the relative position between the support pipe 4 and the upper pipe 5 in the irrigator stand S will be described.

  As shown in FIG. 3A, during the operation of inserting the support pipe 4 into the upper pipe 5, the air in the internal space 4a is compressed, and the air pressure in the internal space 4a increases. At this time, the opening 9d1 of the communication passage 9d is covered by the valve 9e. However, the outside of the irrigator stand S and the internal space 4a are not completely shut off, but are in communication with each other via a communication hole 9e1 provided in the valve body 9e.

  Therefore, the air inside the internal space 4a is discharged to the outside through the communication hole 9e1 having a smaller diameter than the communication passage 9d. As a result, although the resistance at the time of the insertion operation of the upper pipe 5 into the support pipe 4 is larger than the resistance at the time of the withdrawal operation, the resistance in the case of using a type of shock absorber in which the internal space 4a is completely sealed is used. Smaller than

  On the other hand, as shown in FIG. 3B, at the time of the withdrawal operation from the upper pipe 5 of the support pipe 4, the air in the internal space 4a is expanded, and the air pressure in the internal space 4a decreases. At this time, the valve 9e is bent by being pushed by the air flowing into the internal space 4a from the outside of the irrigator stand S through the communication passage 9d, and the opening 9d1 is opened. As a result, air easily flows into the internal space 4a, so that the upper pipe 5 can be easily pulled out of the support pipe 4 with a small force.

  The above-described Illigarter stand S including the shock absorber 9A according to the present embodiment includes the shock absorber 9A, so that the fixing by the fixed handle 7 is not sufficient or the fixing is released to adjust the support height. In the case where the user accidentally releases his hand while performing the operation, the upper pipe 5 does not fall sharply onto the support pipe 4.

  On the other hand, when adjusting the supporting height, the flow rate of the air passing through the communication path between the outside of the irrigator stand S and the internal space 4a of the support pipe 4 is adjusted by the shock absorber 9A. Therefore, the withdrawal operation of the support pipe 4 from the upper pipe 5 can be easily performed with a small force. In addition, the operation of inserting the support pipe 4 into the upper pipe 5 can be performed with a smaller force than an Irrigator stand equipped with a conventional shock absorber that does not discharge air.

  Furthermore, since the valve element 9e is a plate material, the buffering device 9A can easily perform the processing of forming the communication hole 9e1, and the diameter of the communication hole 9e1 can be accurately set to an arbitrary size. That is, the shock absorber 9A can be easily manufactured.

  In the irrigator stand S, when the fixing by the fixing handle 7 is released, the upper pipe 5 falls slowly at a speed corresponding to the diameter of the communication hole 9e1. The falling speed changes according to the weight of the drip bottle or the like suspended from the suspending device 6 and the diameter of the communication hole 9e1 formed in the valve body 9e. That is, the falling speed changes according to the air discharge amount when the communication path 9d is closed by the valve element 9e.

  Since the shock absorber 9A provided in the irrigator stand S is fixed to the upper pipe 5 with the fixing screw 10, it is easy to replace the shock absorber 9A. Further, since the valve element 9e is also fixed to the sealing portion 9b of the shock absorber 9A with the mounting screw 9f, it is easy to replace only the valve element 9e.

  Therefore, when the falling speed of the upper pipe 5 is too slow or too fast, the buffer 9A itself is replaced, or the valve 9e is replaced by one having a different size of the communication hole 9e1. The falling speed can be easily set to a desired speed.

[Second embodiment]
Hereinafter, the shock absorber according to the second embodiment will be described with reference to FIGS. 4 and 5. However, the shock absorber 9B of the present embodiment differs from the above embodiment only in the configuration of the flow rate adjusting means, and therefore only those configurations will be described in detail. In FIG. 5, thick arrows indicate the direction of movement of the support pipe or the shock absorber, and thin arrows indicate the flow of air.

  As shown in FIG. 4, the opening 9d1 on the side of the internal space 4a of the communication passage 9d of the shock absorber 9B is covered by a plate-shaped valve 9g. The valve body 9g is attached to an end face of the sealing portion 9b with an attachment screw 9h. A predetermined interval is provided between the valve body 9g and the head of the mounting screw 9h, and a spring 9i (biasing member) for biasing the valve body 9g to press the opening 9d1 is disposed. Have been.

  A communication hole 9g1 is formed in the valve body 9g to allow the internal space 4a to communicate with the communication passage 9d while the valve body 9g covers the opening 9d1. The diameter of the communication hole 9g1 is smaller than the diameter of the communication passage 9d.

  Therefore, the valve element 9g is movable in the axial direction of the mounting screw 9h. Therefore, the opening 9d1 is closed by the valve 9g when the support pipe 4 and the upper pipe 5 are fixed, and is opened when the valve 9g moves against the urging force of the spring 9i. That is, in the present embodiment, the flow rate adjusting means is constituted by the valve body 9g and the spring 9i.

  Next, with reference to FIG. 5, the function of the shock absorber 9B when changing the relative position between the support pipe 4 and the upper pipe 5 in the Irrigator stand S will be described.

  As shown in FIG. 5A, during the insertion operation of the support pipe 4 into the upper pipe 5, the air in the internal space 4a is compressed, and the air pressure in the internal space 4a increases. At this time, the opening 9d1 of the communication passage 9d is covered by the valve 9g. However, the outside of the irrigator stand S and the internal space 4a are not completely shut off, but are in communication with each other through a communication hole 9g1 provided in the valve body 9g.

  Therefore, the air inside the internal space 4a is discharged to the outside through the communication hole 9g1 having a smaller diameter than the communication passage 9d. As a result, although the resistance at the time of the insertion operation of the upper pipe 5 into the support pipe 4 is larger than the resistance at the time of the withdrawal operation, the resistance in the case of using a type of shock absorber in which the internal space 4a is completely sealed is used. Smaller than

  On the other hand, as shown in FIG. 5B, during the withdrawal operation from the upper pipe 5 of the support pipe 4, the air in the internal space 4a is expanded, and the pressure in the internal space 4a decreases. At this time, the valve element 9g moves toward the head of the mounting screw 9h against the urging force of the spring 9i by being pushed by the air flowing into the internal space 4a from the outside of the irrigator stand S through the communication passage 9d. The opening 9d1 is opened. As a result, air easily flows into the internal space 4a, so that the upper pipe 5 can be easily pulled out of the support pipe 4 with a small force.

  The same effect as that of the shock absorber 9A of the first embodiment can be obtained by the shock absorber 9B of the present embodiment configured as described above.

[Third embodiment]
Hereinafter, the shock absorber according to the third embodiment will be described with reference to FIGS. 6 and 7. However, the shock absorber 9C of the present embodiment is different only in the structures of the shock absorber, the flow rate adjusting means, and the sealing portion of the above embodiment, and thus only those structures will be described in detail. In FIG. 7, thick arrows indicate the direction of movement of the support pipe or the shock absorber, and thin arrows indicate the flow of air.

  As shown in FIG. 6, the opening 9d1 on the side of the internal space 4a of the communication passage 9d of the shock absorber 9C is covered by a flexible plate-shaped valve element 9j (flow rate adjusting means). The valve element 9j is attached to the lower end of the sealing portion 9b with one attachment screw 9f.

  That is, the valve body 9j has a cantilever shape in which the free end on one side in the longitudinal direction covers the opening 9d1 and the other side is fixed to the sealing portion 9b with the mounting screw 9f. Therefore, the opening 9d1 is closed by the valve body 9j when the support pipe 4 and the upper pipe 5 are fixed, and is opened when the valve body 9j is bent.

  A slit 9j1 is formed in the valve body 9j from an end of the valve body 9j on the side remote from the mounting screw 9f toward the center of the valve body 9j. The end of the slit 9j1 on the center side of the valve 9j is located closer to the center of the communication passage 9d than the edge of the communication passage 9d in a state where the valve 9j covers the opening 9d1.

  Therefore, in the cushioning device 9C, when the valve element 9j covers the opening 9d1, a communication hole having a smaller diameter than the opening 9d1 of the communication passage 9d is formed between the slit 9j1 and the edge of the communication passage 9d. The communication hole connects the internal space 4a and the communication passage 9d.

  A rod-shaped stopper 9k is provided in the opening 9d1 of the shock absorber 9C. When the valve element 9j covers the opening 9d1, the stopper 9k contacts the surface of the valve element 9j on the sealing portion 9b side (see FIG. 7A).

  Next, with reference to FIG. 7, the function of the shock absorber 9C when changing the relative position between the support pipe 4 and the upper pipe 5 in the Irrigator stand S will be described.

  As shown in FIG. 7A, during the insertion operation of the support pipe 4 into the upper pipe 5, the air in the internal space 4a is compressed, and the air pressure in the internal space 4a increases. At this time, the opening 9d1 of the communication passage 9d is covered by the valve 9j. However, the outside of the irrigator stand S and the internal space 4a are not completely shut off, and communicate with each other through a communication hole formed by a slit 9j1 provided in the valve body 9j and an edge of the communication passage 9d. It is in the state that was done.

  At this time, even if the pressure in the internal space 4a is suddenly increased due to a fast insertion operation or the like, the valve element 9j contacts the edge of the communication passage 9d and the stopper 9k. 9j does not enter the inside of the communication passage 9d.

  Therefore, the air inside the internal space 4a is formed by the slit 9j1 and the edge of the communication passage 9d, and is discharged to the outside through a communication hole having a smaller diameter than the communication passage 9d. As a result, although the resistance at the time of the insertion operation of the upper pipe 5 into the support pipe 4 is larger than the resistance at the time of the withdrawal operation, the resistance in the case of using a type of shock absorber in which the internal space 4a is completely sealed is used. Smaller than

  On the other hand, as shown in FIG. 7B, during the withdrawal operation from the upper pipe 5 of the support pipe 4, the air in the internal space 4a is expanded, and the pressure in the internal space 4a decreases. At this time, the valve element 9j is bent by being pushed by the air flowing into the internal space 4a from outside the Irrigator stand S through the communication path 9d, and the opening 9d1 is opened. As a result, air easily flows into the internal space 4a, so that the upper pipe 5 can be easily pulled out of the support pipe 4 with a small force.

  With the shock absorber 9C of the present embodiment configured as described above, the same effects as those of the shock absorbers of the other embodiments can be obtained.

  In the present embodiment, in order to prevent the valve body 9j from bending during the insertion operation, a stopper 9k that contacts the valve body 9j is provided at the opening 9d1 of the communication passage 9d. However, the stopper 9k may be omitted if the bending of the valve element 9j during the insertion operation can be sufficiently prevented only by the edge of the communication passage 9d.

[Fourth embodiment]
Hereinafter, the shock absorber according to the fourth embodiment will be described with reference to FIGS. However, the shock absorber 9D of the present embodiment is different from the shock absorber of the above embodiment only in the configuration of the flow rate adjusting means and the sealing portion. Therefore, only those configurations will be described in detail. In FIG. 9, a thick arrow indicates the moving direction of the support pipe or the shock absorber, and a thin arrow indicates the flow of air.

  As shown in FIG. 8, the opening 9d1 on the side of the internal space 4a of the communication passage 9d of the shock absorber 9D is covered with a flexible plate-shaped valve element 91 (flow rate adjusting means). The valve body 91 is attached to the lower end of the sealing portion 9b with one attachment screw 9f.

  That is, the valve body 91 has a cantilever shape in which the free end on one side in the longitudinal direction covers the opening 9d1 and the other side is fixed to the sealing portion 9b with the mounting screw 9f. Therefore, the opening 9d1 is closed by the valve body 91 when the support pipe 4 and the upper pipe 5 are fixed, and is opened when the valve body 9l bends.

  At the lower end of the sealing portion 9b of the shock absorber 9D, a communication hole 9b2 is formed for communicating the internal space 4a with the communication passage 9d while the valve body 91 covers the opening 9d1. The communication hole 9b2 is provided at a position symmetrical to the mounting screw 9f with respect to the axis of the shock absorber 9D. The diameter of the communication hole 9b2 is smaller than the diameter of the opening 9d1.

  Next, with reference to FIG. 9, the operation of the shock absorber 9D when changing the relative position between the support pipe 4 and the upper pipe 5 in the irrigator stand S will be described.

  As shown in FIG. 9A, during the insertion operation of the support pipe 4 into the upper pipe 5, the air in the internal space 4a is compressed, and the air pressure in the internal space 4a increases. At this time, the opening 9d1 of the communication passage 9d is covered by the valve body 9l. However, the outside of the irrigator stand S and the internal space 4a are not completely shut off, but are in communication with each other via a communication hole 9b2 provided in the sealing portion 9b.

  Therefore, the air inside the internal space 4a is discharged to the outside through the communication hole 9b2 having a smaller diameter than the communication passage 9d. As a result, although the resistance at the time of the insertion operation of the upper pipe 5 into the support pipe 4 is larger than the resistance at the time of the withdrawal operation, the resistance in the case of using a type of shock absorber in which the internal space 4a is completely sealed is used. Smaller than

  On the other hand, as shown in FIG. 9B, at the time of the withdrawal operation from the upper pipe 5 of the support pipe 4, the air in the internal space 4a is expanded, and the pressure in the internal space 4a decreases. At this time, the valve body 91 is bent by being pushed by the air flowing into the internal space 4a from the outside of the irrigator stand S through the communication passage 9d, and the opening 9d1 is opened. As a result, air easily flows into the internal space 4a, so that the upper pipe 5 can be easily pulled out of the support pipe 4 with a small force.

  With the shock absorber 9D of the present embodiment configured as described above, the same effects as those of the shock absorbers of the other embodiments can be obtained.

  In the shock absorber 9D, the communication hole 9b2 is provided at a position symmetrical to the mounting screw 9f of the sealing portion 9b with respect to the axis of the shock absorber 9D. However, as in the modification shown in FIG. 10, the communication hole 9b2 may be provided in another position of the sealing portion 9b.

  In addition, as in the modification shown in FIG. 11, the communication hole forms a groove 9b3 communicating with the communication passage 9d in the sealing portion 9b, and a part of the groove 9b3 is formed on the sealing portion 9b side of the valve body 91. You may make it comprise by covering with a surface.

  In the shock absorber 9D of the modification shown in FIGS. 10 and 11, the area where the valve body 91 covers the lower end of the sealing portion 9b is wider than in the shock absorber 9D of the present embodiment shown in FIG. Therefore, it is easy to omit the stopper 9k.

[Fifth Embodiment]
Hereinafter, the shock absorber according to the fifth embodiment will be described with reference to FIGS. However, the shock absorber 9E of the present embodiment differs from the shock absorber of the above embodiment only in the configuration of the flow rate adjusting means, and therefore only those configurations will be described in detail. In FIG. 14, thick arrows indicate the direction of movement of the support pipe or the shock absorber, and thin arrows indicate the flow of air.

  As shown in FIG. 12, the opening 9d1 on the side of the internal space 4a of the communication passage 9d of the shock absorber 9E is covered with a flexible plate-shaped valve 9m. The valve body 9m is attached to the lower end of the sealing portion 9b with one attachment screw 9f.

  That is, the valve element 9m has a cantilever shape in which the free end on one side in the longitudinal direction covers the opening 9d1 and the other side is fixed to the sealing portion 9b with the mounting screw 9f. Therefore, the opening 9d1 is closed by the valve 9m when the support pipe 4 and the upper pipe 5 are fixed, and is opened when the valve 9m is bent.

  A damper part 9n is arranged between the lower end of the sealing part 9b of the shock absorber 9E and the valve body 9m.

  As shown in FIG. 13, an opening 9n1 having a shape corresponding to the opening 9d1 of the communication passage 9d is formed at the center of the damper part 9n. On one side of the opening 9n1, a slit 9n2 communicating from the outer edge to the opening 9n1 is formed. A hole 9n3 through which the mounting screw 9f is inserted is formed on the other side of the opening 9n1. In the shock absorber 9E, the damper part 9n having such a shape is arranged between the lower end of the sealing part 9b and the valve body 9m.

  Therefore, in the shock absorber 9E, when the valve 9m covers the opening 9d1, the slit 9n2 of the damper part 9n, the edge of the communication passage 9d, and the surface of the valve 9m on the sealing portion 9b side are connected. A communication hole having a smaller diameter than the opening 9d1 of the passage 9d is formed, and the communication hole connects the internal space 4a and the communication passage 9d. That is, in the shock absorber 9E, the flow rate adjusting means is constituted by the valve body 9m and the damper part 9n.

  Next, with reference to FIG. 14, the operation of the shock absorber 9E when changing the relative position between the support pipe 4 and the upper pipe 5 in the Irrigator stand S will be described.

  As shown in FIG. 14A, during the operation of inserting the support pipe 4 into the upper pipe 5, the air in the internal space 4a is compressed, and the air pressure in the internal space 4a increases. At this time, the opening 9d1 of the communication passage 9d is covered by the valve 9m. However, the outside of the irrigator stand S and the internal space 4a are not completely shut off. The slit 9n2 of the damper part 9n, the edge of the communication passage 9d, and the surface of the valve body 9m on the side of the sealing portion 9b. It is in a state of being communicated through the formed communication hole.

  Therefore, the air inside the internal space 4a is formed by the slit 9n2 of the damper part 9n, the edge of the communication passage 9d, and the surface of the valve 9m on the sealing portion 9b side, and the communication hole has a smaller diameter than the communication passage 9d. And will be discharged to the outside. As a result, although the resistance at the time of the insertion operation of the upper pipe 5 into the support pipe 4 is larger than the resistance at the time of the withdrawal operation, the resistance in the case of using a type of shock absorber in which the internal space 4a is completely sealed is used. Smaller than

  On the other hand, as shown in FIG. 14B, during the withdrawal operation from the upper pipe 5 of the support pipe 4, the air in the internal space 4a is expanded, and the pressure in the internal space 4a decreases. At this time, the valve 9m is bent by being pushed by the air flowing into the internal space 4a from the outside of the irrigator stand S through the communication passage 9d, and the opening 9d1 is opened. As a result, air easily flows into the internal space 4a, so that the upper pipe 5 can be easily pulled out of the support pipe 4 with a small force.

  According to the shock absorber 9E of the present embodiment configured as described above, the same effects as those of the shock absorbers of the other embodiments can be obtained.

  In the shock absorber 9E of this embodiment, the communication hole is formed by the slit 9n2 of the damper part 9n, the edge of the communication passage 9d, and the surface of the valve 9m on the side of the sealing portion 9b. Therefore, the diameter of the communication hole can be changed only by changing the thickness of the damper part 9n or the width of the slit 9n2. As a result, the flow rate of the air passing through the communication hole becomes easier to control, so that the control of the falling speed becomes easier.

[Sixth embodiment]
Hereinafter, the shock absorber according to the sixth embodiment will be described with reference to FIGS. However, the same components as those in the above embodiment are denoted by the same reference numerals, and description thereof is omitted. In FIG. 17, thick arrows indicate the moving direction of the support pipe or the shock absorber, and thin arrows indicate the flow of air. The arrow in FIG. 18B indicates the flow of air flowing into the internal space 4a from the outside.

  As shown in FIG. 15, the sealing portion 9b of the shock absorber 9F has a small diameter at the distal end. An opening 9d1 of the communication passage 9d and a communication hole 9b4 communicating with the communication passage 9d and having a smaller diameter than the opening 9d1 are formed on the peripheral surface of the small diameter portion. A damper part 9o (flow rate adjusting means) is attached to the small diameter portion.

  As shown in FIG. 16, the damper part 9o has a shape in which a slit 9o1 extending in the axial direction is formed in a cylinder. The damper part 9o is formed of a member having flexibility.

  As shown in FIG. 15A, a plurality of holding portions 9b5 formed so as to protrude in the radial direction are formed at the distal end portion of the small-diameter portion of the sealing portion 9b. The sealing portion 9b holds the damper part 9o so as to be sandwiched between the lower end surface of the large diameter portion and the upper end surface of the holding portion 9b5. Therefore, the movement of the damper part 9o in the axial direction of the shock absorber 9F is restricted.

  Further, a rotation preventing portion 9b6 formed so as to protrude in the radial direction is formed above the communication hole 9b4 in the small diameter portion of the sealing portion 9b. The rotation preventing portion 9b6 has a width corresponding to the width of the slit 9o1 of the damper part 9o, and is inserted into the slit 9o1 when the damper part 9o is attached to the sealing portion 9b. Therefore, the rotation of the damper part 9o around the axis of the shock absorber 9F is restricted by the rotation prevention part 9b6.

  The opening 9d1 is covered by a damper part 9o. Therefore, the opening 9d1 is closed by the damper part 9o when the support pipe 4 and the upper pipe 5 are fixed (see FIG. 18A), and is opened when the damper part 9o bends (see FIG. 18B).

  The communication hole 9b4 is located below the rotation preventing portion 9b6 that fixes the position of the slit 9o1 of the damper part 9o. Therefore, even when the support pipe 4 and the upper pipe 5 are fixed, or when the damper part 9o is bent, the open state is maintained.

  Next, with reference to FIGS. 17 and 18, the operation of the shock absorber 9F when changing the relative position between the support pipe 4 and the upper pipe 5 in the Irrigator stand S will be described.

  As shown in FIG. 17A, during the operation of inserting the support pipe 4 into the upper pipe 5, the air in the internal space 4a is compressed, and the air pressure in the internal space 4a increases. At this time, as shown in FIG. 18A, the damper part 9o that covers the opening 9d1 of the communication passage 9d is not deformed. However, the outside of the irrigator stand S and the internal space 4a are not completely shut off, but are in communication with each other via a communication hole 9b4 not covered with the damper part 9o.

  Therefore, the air inside the internal space 4a is discharged to the outside through the communication hole 9b4 having a smaller diameter than the communication passage 9d. As a result, although the resistance at the time of the insertion operation of the upper pipe 5 into the support pipe 4 is larger than the resistance at the time of the withdrawal operation, the resistance in the case of using a type of shock absorber in which the internal space 4a is completely sealed is used. Smaller than

  On the other hand, as shown in FIG. 17B, at the time of the withdrawal operation from the upper pipe 5 of the support pipe 4, the air in the internal space 4a is expanded, and the air pressure in the internal space 4a decreases. At this time, as shown in FIG. 18B, the damper part 9o is bent by being pushed by the air flowing into the internal space 4a from the outside of the irrigator stand S through the communication passage 9d, and the opening 9d1 is opened. As a result, air easily flows into the internal space 4a, so that the upper pipe 5 can be easily pulled out of the support pipe 4 with a small force.

  With the shock absorber 9F of the present embodiment configured as described above, the same effects as those of the shock absorbers of the other embodiments can be obtained.

[Other Embodiments]
Although the illustrated embodiment has been described above, the present invention is not limited to such an embodiment.

  For example, in the above-described embodiment, an irrigator stand provided with a shock absorber is described. However, the shock absorber of the present invention is not only applicable to an irrigator stand, but also to a column having an outer cylinder and an inner member that can be inserted into and removed from the outer cylinder. It can be adopted.

  Further, in the first to fifth embodiments, the valve body is fixed when the support pipe and the upper pipe are fixed (that is, the relative position is not changed) and when the outer cylinder is inserted into the inner member. The opening of the communication passage is covered, and the opening is opened at the time of the pulling-out operation. This is because when the sudden fall of the upper pipe 5 to the support pipe 4 occurs suddenly, the fall speed is rapidly reduced.

  However, the present invention is not limited to such a configuration, and the valve element opens the opening when the support pipe and the upper pipe are fixed and when the inner member is pulled out from the outer cylinder, The opening may be closed during the insertion operation.

  For example, as in the second embodiment, when the flow rate adjusting means is constituted by the valve body 9g and the spring 9i for urging the valve body 9g, the spring 9i is formed by the valve body 9g and the head of the mounting screw 9h. Instead of being disposed between the valve body 9g and the sealing portion 9b (see FIG. 5).

  Further, in the third to sixth embodiments, the flow rate adjusting means is constituted by using a valve element constituted by a flexible plate-shaped member. However, as in the second embodiment, the flow rate adjusting means may be configured using a valve body and a spring for biasing the valve body.

  Further, in the shock absorber 9C of the third embodiment, in order to prevent the valve body 9j from being bent during the insertion operation, the stopper 9k that comes into contact with the valve body 9j is provided in the opening 9d1 of the communication passage 9d. I have. However, the configuration of providing such a stopper is not applied only to the shock absorber 9C of the third embodiment. For example, the present invention may be applied to the shock absorber of the other embodiments described above.

DESCRIPTION OF SYMBOLS 1 ... Base part, 2 ... Leg part, 3 ... Caster, 4 ... Support pipe (outer cylinder), 4a ... Internal space, 5 ... Upper pipe (inner member), 5a ... Upper pipe side fixing hole, 6 ... Hanging tool, 7 ... fixed handle, 8 ... handle, 9A, 9B, 9C, 9D, 9E, 9F ... shock absorber, 9a ... insertion portion, 9a1 ... shock absorber side fixing hole, 9b ... sealing portion, 9b1 ... annular concave portion, 9b2 ... communication Hole, 9b3 groove, 9b4 communication hole, 9b5 holding part, 9b6 rotation prevention part, 9c O-ring, 9d communication path, 9d1 opening, 9e, 9g, 9j, 9l, 9m valve body 9e1, 9g1 communication hole, 9f, 9h mounting screw, 9i spring (biasing member), 9j1 slit, 9k stopper, 9n damper part, 9n1 opening, 9n2 slit, 9n3 hole, 9o ... damper parts, 9o1 ... slit 10 ... fixing screws, S ... stand.

Claims (3)

A shock absorber that is provided on an inner member that can be inserted into and removed from the outer cylinder, and that is slidable in close contact with the inner peripheral surface of the outer cylinder when the inner member is inserted into the outer cylinder,
A communication passage for communicating the internal space of the outer cylinder with the outside,
A communication hole smaller in diameter than the communication passage;
When the inner member is inserted into the outer cylinder, the opening of the communication passage is closed and fluid flows through the communication hole, and when the inner member is withdrawn from the outer cylinder, the opening is closed. and a flow rate adjusting means for opening a
The flow rate adjusting means is located at a position away from the opening when the outer cylinder and the inner member are fixed and when the inner member is pulled out from the outer cylinder, and the opening is opened, and When the material is inserted into the outer cylinder, the opening is closed by being pushed in a direction to cover the opening by a force received from a fluid that is going to flow out of the internal space to the outside through the communication path. A shock absorber characterized by doing. An outer cylinder erected on a base, an inner member inserted from an upper opening of the outer cylinder and sliding in close contact with an inner peripheral surface of the outer cylinder, and an inner member provided at a lower end portion of the inner member; A shock absorber for reducing the falling speed of the inner member when descending, and a telescopic medical stand having:
The shock absorber is a bottomed cylindrical shape,
A sealing portion that is in air-tight contact with the inner peripheral surface of the outer cylinder,
A small-diameter portion having a smaller diameter than the sealing portion at the lower end of the sealing portion,
A communication passage that is formed to penetrate the side wall of the small-diameter portion, communicates with the internal space of the outer cylinder through the shock-absorbing device and the outside, and is formed so as to penetrate the small-diameter portion, A communication hole having a smaller diameter than the communication path for communicating the space with the outside through the shock absorber;
On the outer peripheral surface of the small diameter portion, a cylindrical elastically deformable flexible damper part inserted so as to cover the communication path,
The damper part is formed in a C-shape in plan view by having a vertically extending slit in a part of a cylindrical peripheral wall, and an outer peripheral surface thereof has a predetermined interval with an inner peripheral surface of the outer cylinder. And
The medical stand, wherein only when the inner member is lifted, the medical stand is detached from the small-diameter portion by being pushed by the external air moving toward the internal space of the outer cylinder through the communication passage. A shock absorber that is provided at a lower end portion of an inner member that can be inserted into and removed from the outer cylinder and that can be slid in close contact with the inner peripheral surface of the outer cylinder when the inner member is inserted into the outer cylinder,
A communication passage for communicating the internal space of the outer cylinder with the outside,
A communication hole smaller in diameter than the communication passage;
When the inner member is inserted into the outer cylinder, the opening of the communication passage is closed and fluid flows through the communication hole, and when the inner member is withdrawn from the outer cylinder, the opening is closed. Bei example and a flow rate adjustment means for opening the,
The flow rate adjusting means includes a plate-shaped valve body that covers the opening, and a mounting screw that attaches the valve body to a lower end of the shock absorber by screwing into a screw hole provided around the opening. A spring disposed between the valve body and the head of the mounting screw for urging the valve body to press the valve body against the opening. And the length of a portion of the mounting screw inserted into the screw hole when the spring is mounted,
The valve body closes the opening at a position covering the opening when the outer cylinder and the inner member are fixed and when the inner member is inserted into the outer cylinder, and the inner member is closed. During the withdrawal operation from the outer cylinder, the spring is compressed by a force received from a fluid flowing into the inner space of the outer cylinder from the outside through the communication path, and moves in a direction away from the opening by being compressed. A shock absorber, wherein the opening is opened .