WO2017094375A1

WO2017094375A1 - Pipe connection structure

Info

Publication number: WO2017094375A1
Application number: PCT/JP2016/080789
Authority: WO
Inventors: 大洋緒方; 吉則形谷; 英俊河西; 隼人池田
Original assignee: 株式会社荏原製作所
Priority date: 2015-12-01
Filing date: 2016-10-18
Publication date: 2017-06-08
Also published as: JP2017101725A

Abstract

The present invention pertains to a pipe connection structure applied to pipes through which a working fluid for a fluid coupling flows. The pipe connection structure comprises: a connection pipe (34) through which the working fluid for the fluid coupling flows; a support member (35) having a through hole (35a) into which the connection pipe (34) is inserted; an annular seal (48) that seals a gap between an outer circumferential surface (34a) of the connection pipe (34) and the through hole (35a); and a flange member (66) that presses the annular seal (48) against the support member (35). The diameter of the outer circumferential surface (34a) of the connection pipe (34) is smaller than the diameter of the through hole (35a).

Description

Piping connection structure

The present invention relates to a pipe connection structure for connecting one pipe to the other pipe, and more particularly to a pipe connection structure applied to a pipe through which a working fluid of a fluid coupling flows.

The fluid coupling is a device that transmits the rotation of the input shaft to the output shaft via the working fluid that exists between the impeller that is the input-side impeller and the runner that is the output-side impeller. For example, hydraulic oil is used as the working fluid. The fluid coupling includes a scoop tube (rake pipe) that increases or decreases the amount of working fluid in a fluid chamber formed between the impeller and the runner. By increasing or decreasing the amount of working fluid in the fluid chamber, the rotational speed of the output shaft relative to the input shaft can be changed steplessly.

Since the working fluid is rotated at high speed by the impeller, the pressure and temperature of the working fluid increase. For example, the working fluid temperature can reach 100 degrees. The hot working fluid scooped up by the scoop tube is sent to the fluid cooling device, cooled by the fluid cooling device, and then returned to the fluid chamber.

JP-A-10-196686

The working fluid circulates between the fluid chamber and the fluid cooling device through the piping. However, as described above, since the working fluid becomes high temperature, the piping expands due to the heat of the working fluid, and a load is applied to the piping and the connection portion between the pipings. And this causes damage to the piping and damage to the connecting portion, which may cause the working fluid to leak.

The present invention has been made in view of the above-described problems, and provides a pipe connection structure capable of preventing damage to a pipe and damage to a connection portion between pipes even when thermal expansion of the pipe occurs. For the purpose.

In order to achieve the above-described object, one aspect of the present invention includes a connection pipe through which a working fluid of a fluid coupling flows, a support member having a through hole into which the connection pipe is inserted, an outer peripheral surface of the connection pipe, and the An annular seal that seals a gap between the through hole and a flange member that presses the annular seal against the support member, and the diameter of the outer peripheral surface of the connection pipe is smaller than the diameter of the through hole This is a characteristic pipe connection structure.

In a preferred aspect of the present invention, the through hole has an annular inclined surface that gradually expands toward an end of the through hole, and the annular seal includes the annular inclined surface, the outer peripheral surface of the connection pipe, It is in contact with the flange member.
In a preferred aspect of the present invention, the connecting pipe is made of metal.
In a preferred aspect of the present invention, an external pipe having an external flange connected to the flange member is further provided.
In a preferred aspect of the present invention, a gap is formed between an end portion of the connection pipe and an end portion of the external pipe.
In a preferred aspect of the present invention, an inner diameter of the flange member is larger than a diameter of an outer peripheral surface of the connection pipe.

According to the present invention, since the connecting pipe is gently inserted into the through hole of the support member, the connecting pipe is allowed to move in the axial direction when the connecting pipe is thermally expanded. Therefore, no load is applied to the connecting pipe, and the connecting pipe can be prevented from being damaged. Furthermore, since the annular seal seals the gap between the outer peripheral surface of the connecting pipe and the through hole, the working fluid can be prevented from leaking.

It is a top view which shows a fluid coupling typically. It is sectional drawing which shows one Embodiment of piping connection structure.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a plan view schematically showing a fluid coupling. As shown in FIG. 1, the fluid coupling includes an impeller 1 and a runner 2 arranged to face each other, a drive shaft 11 to which the impeller 1 is fixed, and an output shaft 12 to which the runner 2 is fixed. The impeller 1 is also called an input side impeller, and the runner 2 is also called an output side impeller. The impeller 1 and the runner 2 each have a hemispherical shape having a plurality of radial blades inside, and a fluid chamber 5 is formed between the impeller 1 and the runner 2.

The input shaft 15 is arranged in parallel with the drive shaft 11. The input shaft 15 is supported by

radial bearings

16 and 17. A large gear 21 is fixed to the input shaft 15, and a small gear 22 that meshes with the large gear 21 is fixed to the drive shaft 11. The end of the input shaft 15 is connected to a prime mover (not shown) such as an electric motor or a gas turbine. The rotation of the prime mover is transmitted from the input shaft 15 to the drive shaft 11 via the large gear 21 and the small gear 22.

The fluid coupling includes a working fluid circulation system 25 that supplies a working fluid to a fluid chamber 5 formed between the impeller 1 and the runner 2, and a scoop tube for increasing or decreasing the amount of the working fluid in the fluid chamber 5 ( Rake pipe) 30. The tip 30 a of the scoop tube 30 is located in the impeller casing 7. The impeller casing 7 is fixed to the impeller 1 and has a shape surrounding the runner 2. The impeller casing 7 rotates together with the impeller 1.

An actuator 31 such as a hydraulic servo is connected to the scoop tube 30, and the scoop tube 30 can be moved in the radial direction of the impeller 1 and the runner 2 by the actuator 31. When the impeller 1 and the impeller casing 7 are rotating, the working fluid (for example, hydraulic oil) is held in the rotating impeller casing 7. The working fluid in the impeller casing 7 flows by the rotating impeller 1, and the flowing working fluid rotates the runner 2.

When the impeller 1 is rotating, centrifugal force is generated in the working fluid, and the pressure of the working fluid increases. The tip 30 a of the scoop tube 30 scoops the working fluid in the impeller casing 7, and the working fluid passes through the scoop tube 30 and is discharged from the impeller casing 7. The working fluid circulation system 25 includes a fluid cooling device 26 for cooling the working fluid, and a working fluid circulation line 27 extending through the fluid cooling device 26. The inlet of the working fluid circulation line 27 is connected to the scoop tube 30, and the outlet of the working fluid circulation line 27 communicates with the fluid chamber 5 between the impeller 1 and the runner 2.

The working fluid discharged from the impeller casing 7 through the scoop tube 30 flows through the working fluid circulation line 27 and is sent to the fluid cooling device 26. The working fluid is cooled by heat exchange with the cooling water, and then returned to the fluid chamber 5 through the working fluid circulation line 27. In this way, the working fluid circulates between the fluid chamber 5 and the fluid cooling device 26 by its own pressure raised by the rotating impeller 1.

The impeller 1 is fixed to the drive shaft 11 and the runner 2 is fixed to the output shaft 12. The rotation of the drive shaft 11 is transmitted from the impeller 1 to the runner 2 via the working fluid, and the output shaft 12 rotates. The rotational speed of the runner 2 varies depending on the amount of working fluid in the fluid chamber 5 formed between the impeller 1 and the runner 2. Specifically, the rotation speed of the runner 2 increases as the amount of working fluid increases.

The amount of working fluid in the fluid chamber 5 varies depending on the position of the scoop tube 30. That is, when the tip 30a of the scoop tube 30 moves radially outward, the amount of working fluid decreases, and when the tip 30a of the scoop tube 30 moves radially inward, the amount of working fluid increases. Thus, by operating the scoop tube 30 with the actuator 31, the amount of working fluid in the fluid chamber 5, that is, the rotational speed of the output shaft 12 can be changed.

FIG. 2 is a cross-sectional view showing an embodiment of the pipe connection structure. As shown in FIG. 2, the pipe connection structure includes a connection pipe 34 through which a working fluid of a fluid coupling flows, and a support member 35 having a through hole 35 a into which the connection pipe 34 is inserted. The support member 35 is a casing that houses components such as the impeller 1 and the runner 2 described above.

The connecting pipe 34 is made of metal. The diameter of the outer peripheral surface 34 a of the connection pipe 34 (that is, the outer diameter of the connection pipe 34) is slightly smaller than the diameter of the through hole 35 a, and the connection pipe 34 is supported by the support member 35. Since the connecting pipe 34 is gently inserted into the through hole 35a of the support member 35, the connecting pipe 34 is allowed to move in the axial direction. Therefore, one end 34b of the connection pipe 34 is a free end.

The other end 34c of the connecting pipe 34 is fixed to the fixing member 33 by a fastener 44 such as a screw. Therefore, the end 34c of the connection pipe 34 is a fixed end. The fixing member 33 is, for example, a pipe through which the working fluid discharged through the scoop tube 30 described above flows, or another pipe. The connection pipe 34 constitutes a part of the working fluid circulation line 27 described above.

An annular seal 48 is provided on the outer peripheral surface 34 a of the connection pipe 34 to seal a gap between the outer peripheral surface 34 a of the connection pipe 34 and the through hole 35 a of the support member 35. The through hole 35a of the support member 35 has an annular inclined surface 55 that gradually widens toward the end of the through hole 35a. The annular seal 48 is disposed between the outer peripheral surface 34 a of the connection pipe 34 and the annular inclined surface 55. The annular seal 48 is, for example, an O-ring.

The outer peripheral surface 34a of the connecting pipe 34 has a tapered surface 56 in which the tip of the connecting pipe 34 is gradually narrowed toward the end 34b. The tapered surface 56 is formed by grinding, for example. In a state where the connection pipe 34 is supported by the support member 35, the annular seal 48 is guided by the tapered surface 56 and attached to the outer peripheral surface 34 a of the connection pipe 34. As described above, by providing the tapered surface 56, the annular seal 48 can be mounted on the outer peripheral surface 34 a of the connection pipe 34 without damaging the annular seal 48.

The annular seal 48 is pressed against the annular inclined surface 55 of the support member 35 by an annular flange member 66. The flange member 66 is connected to the outer flange 61 of the outer tube 60 by a plurality of screws 75. An annular seal member 71 is disposed between the flange member 66 and the outer flange 61. The seal member 71 is, for example, an annular gasket. The screw 75 extends through the external flange 61, the seal member 71, and the flange member 66, and is screwed into a plurality of screw holes 35 c formed in the support member 35. The other end of the external pipe 60 is connected to the fluid cooling device 26 described above, for example.

The flange member 66 is in contact with the end surface 35b of the support member 35, and the flange member 66 and the connection pipe 34 are disposed concentrically. The inner diameter of the flange member 66 is larger than the diameter of the outer peripheral surface 34a of the connection pipe 34 and further larger than the diameter of the through hole 35a so that the flange member 66 does not hinder the movement of the connection pipe 34 in the axial direction. Therefore, the flange member 66 is not in contact with the connection pipe 34. The annular seal 48 is in contact with the annular inclined surface 55 of the support member 35, the outer peripheral surface 34 a of the connection pipe 34, and the flange member 66.

The connecting pipe 34 is separated from the outer pipe 60. More specifically, a gap 80 is formed between the free end 34 b of the connection pipe 34 and the end 60 a of the outer pipe 60. The gap 80 has such a size that it does not come into contact with the outer pipe 60 even if the connection pipe 34 expands due to the heat of the working fluid. The working fluid flowing through the connection pipe 34 flows into the outer pipe 60 through the gap 80.

When the screw 75 is tightened, the gap between the flange member 66 and the external flange 61 is sealed by the seal member 71. At the same time, the annular seal 48 is pressed against the annular inclined surface 55 of the support member 35 by the flange member 66, and the annular seal 48 is guided by the annular inclined surface 55 and strongly pressed against the outer peripheral surface 34 a of the connection pipe 34. As a result, the annular seal 48 seals the space between the end surface 35 b of the support member 35 and the flange member 66 and the clearance between the through hole 35 a of the support member 35 and the outer peripheral surface 34 a of the connection pipe 34. Therefore, the annular seal 48 can prevent the working fluid from leaking.

According to this embodiment, the connection pipe 34 is gently inserted into the through hole 35a of the support member 35, and the connection pipe 34 is not in contact with the external pipe 60. The annular seal 48 is in close contact with the outer peripheral surface 34a of the connection pipe 34, but does not constrain the position of the connection pipe 34 in the axial direction. Therefore, even if the connection pipe 34 expands in the axial direction due to the heat of the working fluid, no stress is generated in the connection pipe 34, and as a result, the connection pipe 34 can be prevented from being damaged.

Furthermore, according to the present embodiment, by providing the annular seal 48, the working fluid can flow between the outer peripheral surface 34 a of the connection pipe 34 and the through hole 35 a of the support member 35 and / or the end surface 35 b of the support member 35 and the flange member. It is possible to prevent leakage from the space 66.

The above-described embodiments are described for the purpose of enabling the person having ordinary knowledge in the technical field to which the present invention belongs to implement the present invention. Various modifications of the above embodiment can be naturally made by those skilled in the art, and the technical idea of the present invention can be applied to other embodiments. Accordingly, the present invention is not limited to the described embodiments, but is to be construed in the widest scope according to the technical idea defined by the claims.

The present invention can be used for a pipe connection structure applied to a pipe through which a working fluid of a fluid coupling flows.

DESCRIPTION OF SYMBOLS 1 Impeller 2 Runner 5 Fluid chamber 7 Impeller casing 11 Drive shaft 12 Output shaft 15

Input shaft

16, 17 Radial bearing 21 Large gear 22 Small gear 25 Working fluid circulation system 26 Fluid cooling device 27 Working fluid circulation line 30 Scoop tube 30a Tip 31 Actuator 33 Fixed member 34 Connecting pipe 34a Outer peripheral surface 34b Free end 34c Fixed end 35 Support member 35a Through hole 35b End surface 35c Screw hole 44 Fastener 48 Annular seal 55 Annular slope 56 Tapered surface 60 External tube 60a End 61 External flange 66 Flange Member 71 Seal member 75 Screw 80 Clearance

Claims

A connecting pipe through which the working fluid of the fluid coupling flows;
A support member having a through hole into which the connection pipe is inserted;
An annular seal that seals the gap between the outer peripheral surface of the connecting pipe and the through hole;
A flange member that presses the annular seal against the support member;
A pipe connection structure, wherein a diameter of an outer peripheral surface of the connection pipe is smaller than a diameter of the through hole.
The through hole has an annular slope that gradually spreads toward the end of the through hole;
The pipe connection structure according to claim 1, wherein the annular seal is in contact with the annular inclined surface, an outer peripheral surface of the connection pipe, and the flange member.
The pipe connection structure according to claim 1 or 2, wherein the connection pipe is made of metal.
The pipe connection structure according to any one of claims 1 to 3, further comprising an outer pipe having an outer flange coupled to the flange member.
The pipe connection structure according to claim 4, wherein a gap is formed between an end of the connection pipe and an end of the external pipe.
The pipe connection structure according to any one of claims 1 to 5, wherein an inner diameter of the flange member is larger than a diameter of an outer peripheral surface of the connection pipe.