JP2519447B2 - Refrigerant piping structure of engine driven heat pump device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a refrigerant piping structure of an engine driven heat pump device.

[Conventional technology]

There is an engine-driven heat pump device that elastically supports a compressor to reduce noise and vibration.

If this system is adopted, the refrigerant piping system extending from the compressor needs to be flexible, and the refrigerant piping system is subject to internal pressure by the refrigerant, and the airtightness of the piping is required. A metal bellows tube such as is adopted as part of the way.

Then, the bellows tube portion is caused to intensively bend the entire piping system to protect the entire piping system (see, for example, Japanese Patent Application No. 60-218016).

[Problems to be solved by the invention]

By the way, if such a configuration is adopted, vibration of the compressor or the like causes concentration of stress in the mouthpiece portion that is a connection portion between the end portion of the bellows pipe and the pipe made of copper pipe, etc. It is advantageous to prolong the service life of the refrigerant pipe of the engine-driven heat pump device in which the compressor is elastically supported.

The present invention has been made based on this point of view, and is intended to prolong the service life of this type of refrigerant pipe.

[Means for solving problems]

Therefore, according to the present invention, in a refrigerant pipe of an engine-driven heat pump device of this type, an expanded guide cylinder portion extending toward the metal bellows pipe is formed in the mouthpiece, and the inner surface of the guide cylinder portion and the vibration absorbing portion are formed. A gap is formed between the outer peripheral surface of the tube.

[Action]

Since a guide tube portion having an expanded shape extending toward the metal bellows tube is formed on the base and the inner surface of the guide tube portion and the outer peripheral surface of the vibration absorbing tube are separated from each other, they are fixed by welding or the like. It is possible to prevent excessive bending of the metal bellows pipe in the vicinity of the closed part, and the length of the bellows pipe that can be vibrated by the excitation force from the compressor etc. is shortened by installing the guide tube part. Since this does not occur, it is possible to take measures without increasing the stress per unit length of the bellows pipe during normal vibration, and it is possible to extend the life of the cooling pipe.

Further, since the guide tube portion is simply formed on the base, there is an advantage that it is possible to easily take measures.

〔Example〕

 The present invention will be described below with reference to the embodiments shown in the drawings.

The figure shows a power unit of an engine-driven heat pump device according to the present invention, where 1 is an engine driven by gas fuel such as city gas or propane gas, and 2 is a compressor supported and fixed on the upper part of the engine 1.

In addition to the compressor 2, the engine 1 is an assembly in which other auxiliary equipment such as an exhaust gas heat exchanger 6 having a sound deadening function is assembled.

A V-belt 3 is wound between a drive pulley 4 mounted on the engine 1 side and a driven pulley 5 mounted on the compressor 2 side, and the power of the engine 1 is compressed via the V-belt 3. It is designed to be transmitted to aircraft 2.

The assembly of the compressor 2 and the like configured as described above is supported in the vicinity of its center of gravity G through an elastic material F on a pillar E standing on the base plate at the lower part of the housing for vibration isolation. It can swing in any direction.

A discharge pipe 7 and a suction pipe 8 are connected to the compressor 2, and the refrigerant compressed by the compressor 2 is pressure-fed from the pipe 7 to the refrigerant circulation system, so that an air heat exchanger in another housing is connected. After that, it is returned to the pipe 8 again.

The vibration absorption pipes 9a, 9b, 10a, 1
0b is connected, and each end 7a, 8a of the pipe is connected to a connecting portion 11, 12 fixed to the upper wall of the housing.

The vibration absorbing tubes 9a, 9b, 10a, 10b are made of stainless steel wire mesh 13
It consists of a stainless steel bellows tube 14 covered with, and since this stainless steel bellows tube 14 has a structure that can absorb bending but not expansion and contraction, each pipe 7, 8 is designed to absorb vibrations of three axes x, y, z. Both use two.

In this specification, the term “bellows tube” is a concept that includes both the annular protrusion and the spiral protrusion formed on the peripheral surface of the pipe.

The ends of the vibration absorbing tubes 9a, 9b, 10a, 10b are all configured and connected as shown in FIG.

That is, a base 15 made of stainless steel is attached to the end of the bellows pipe 14.
Is fixed by silver brazing 16, and the other end of the base 15 is airtightly fixed by brazing to the pipe 7 made of a copper pipe. A metal sleeve 17 is welded and attached to the outer periphery of the mouthpiece 15 near the open end on the bellows pipe 14 side, and a guide cylinder portion 18 is attached to the tip of the metal sleeve 17.

The guide tube portion 18 is made of a metal pipe and has a widened front end side. The end surface shape of the guide tube portion 18 on the mouthpiece 15 side is almost the same as the shape of the mouthpiece 15 and is installed concentrically. There is. This is because when the metal bellows tube 14 disposed inside thereof vibrates due to the excitation force, its vibrating posture is favorably maintained.

Further, the guide tube portion 18 in this embodiment has a pre-opening shape in which the expanded shape is curved, so that an excessive vibration force is applied to the metal bellows tube 14 and the metal becomes large even when the amplitude becomes large. The bellows tube 14 is prevented from coming into contact with the opening end edge of the guide tube portion 18 and locally receiving bending stress locally.

In this embodiment, the mouthpiece 15, the metal sleeve 17 and the guide tube portion 18 are thus constituted.
After performing the silver brazing work with 14, the guide tube part 18
It is because of the work procedure that was decided to be installed on the
It goes without saying that the guide tube portion 18 may be formed integrally with the base 15 as shown in the figure.

Further, since a gap S is formed between the inner surface of the guide tube portion 18 and the outer surface of the metal net 13 that covers the outer side of the metal bellows tube 14, a normal excitation force of the compressor 2 or the like is generated. The length of the metal bellows tube 14 that can be vibrated is the interval between the bases 15 and 15, and the stress can be distributed over the entire length of the metal bellows tube 14 to share the stress. Be beneficial.

In addition, the connecting portions 11 and 12 on the wall surface of the housing from the compressor 2
The vibration absorbing pipes 9a, 9b, 10a, 10b having elasticity are connected to the pipes 7, 8 adapted to be connected to the pipes 7, 8 from the engine 1 or the compressor 2 to the pipes 7, 8. The vibration transmitted to 8 is absorbed on the way, which has the advantage of preventing the occurrence of resonance of the housing.

Next, another embodiment shown in FIG. 4 will be described.
In this embodiment, the structures of the base 15 and the guide cylinder portion 18 are different from those of the above-described embodiment, and other points are almost the same as those of the previous embodiment. Therefore, the same reference numerals as in the previous embodiment are given. Detailed description is omitted.

The mouthpiece 15 of this embodiment is one in which the large-diameter portion 15a and the small-diameter portion 15b are formed as separate cylindrical bodies, and these are fixed and integrated with a silver braze 16 to form the mouthpiece of the embodiment. It is equivalent to 15.

This includes the large diameter portion 15a, the wire mesh 13 and the metal bellows tube 14.
This is because the workability of fixing with the silver brazing filler metal 16 is taken into consideration.
Connection with is also made.

The tip portion (left side in FIG. 4) of the large-diameter portion 15a is extended leftward, and the tip has a curved and expanded shape so that the guide tube portion 18 is integrated with the large-diameter portion 15a. Has been formed. Therefore, it is not necessary to prepare a special component for forming the guide tube portion 18, and the brazing operation described above is easy, so that there is an advantage that it can be easily manufactured.

Next, another embodiment shown in FIG. 5 will be described. In the description of this embodiment described below, the same reference numerals as those of the previous embodiment are used in respect of being similar to the previously described embodiment. Is added and detailed description is omitted.

The embodiment shown in FIG. 5 is designated by the reference numeral in FIG.
Shows the vibration absorber tube designated as 10a, this vibration absorber tube 1
Regarding the caps 15, 15 at both ends of 0a, FIG. 5 shows the cap 15 on the right side in FIG. 2 as 15R in FIG. 5 and conversely as 15L on the left side.

The caps 15R and 15L on both sides are formed in the same shape as the embodiment described with reference to FIG. 4, and the guide tube portion 18 is integrally formed at the tip thereof.

Then, both ends of the vibration absorbing tube 10a are fixed to the caps 15R and 15L by brazing as described with reference to FIG.

 The distance between these fixed points is indicated by A in the figure.

A gap S is formed in each of the guide cylinders 18 of the caps 15R and 15L, and the rear end side (the pipe 8 side to be connected) of the caps is connected to the guide cylinders 18 of the caps. The inner peripheral surface is the outer peripheral surface of the vibration absorbing pipe 10a (specifically, the wire mesh 1
The outer peripheral surface of 3) is formed with a close contact portion B having a reduced diameter.

The length of the close contact portion B is shown in FIG.
Shown as B1 and B2.

As a result, the portion of the vibration absorbing tube 10a that can be displaced in the radial direction becomes the portion indicated by A in FIG.

Here, the function of the close contact portion B will be explained. Although the vibration absorbing tube 10a is restrained from being displaced in the radial direction at the close contact portion B, it can be slightly expanded and contracted in the axial direction.

That is, the vibration absorbing tube 10a is attached to the caps 15R and 15L.
Since the radial displacement is suppressed, the bending moment does not act on the end portion of the vibration absorbing tube 10a integrally fixed to the base by the braze 16, and the risk of breakage here is reduced.

In addition, since the vibration absorbing tube 10a can be expanded and contracted to some extent in the close contact portion B, it functions as an adjustment allowance for the expansion and contraction displacement amount associated with the displacement of the vibration absorbing tube 10a that is bent by the excitation force. Also has.

A guide tube portion 18 is formed in an expanded shape at the tip end side of the close contact portion B of the mouthpieces 15R and 15L, and a gap S having a triangular cross section is formed between the guide cylinder portion 18 and the outer peripheral surface of the vibration absorbing tube 10a. ing.

Particularly, in this embodiment, the base 15R has an expanded shape with a small curvature, while the base 15L has an expanded shape with a large curvature. Also, these caps 15R, 15L
In the above, in the contact portion B, B2 is formed longer than B1.

This is because the base 15R is fixed to the assembly that is the vibration source, as is clear from FIG. 2, and a large bending force is applied by this excitation force compared to the base 15L, so the stress caused by this is vibrated. This is because the absorption tube 10a is dispersed over a wider range to reduce the stress.

〔The invention's effect〕

As described above, in the refrigerant pipe of the engine-driven heat pump device of this type, the present invention forms, in the mouthpiece, a guide tube portion having an expanded shape extending toward the metal bellows tube, and the inner surface of the guide tube portion and the guide tube portion. Since a gap is formed between the vibration absorbing pipe and the outer peripheral surface, it is possible to prevent excessive bending of the metal bellows pipe in the vicinity of the portion fixed by welding etc. at the local part, and from the compressor etc. Since the length of the bellows tube that can vibrate due to the excitation force of the bellows is not shortened by this, it is possible to take measures against normal vibrations without increasing the stress per unit length of the bellows tube, and to extend the life of the refrigerant pipe. Can be achieved.

In addition, since the guide tube portion is simply formed on the mouthpiece, there is an advantage that it is possible to take measures with a simple structure.

[Brief description of drawings]

The drawings relate to the embodiment of the present invention, and FIG.
2 is a schematic view of a power unit of an engine driven heat pump device, FIG. 3 is a view taken along the line III-III in FIG. 2, and FIG. 4 is a sectional view corresponding to FIG. 1 of another embodiment. The figure is a sectional view of still another embodiment. B ... Close part, S ... Gap, 1 ... Engine, 2 ... Compressor, 7,8 ... Piping, 9a, 9b, 10a, 10b ... Vibration absorption pipe, 14 ... Bellows pipe, 15 ... … Clasp, 17 …… cylinder, 18 …… guide cylinder.

Claims (2)

(57) [Claims] Claim: What is claimed is: 1. An engine and a compressor driven by the engine are elastically supported, and a vibration absorbing pipe made of a metal bellows pipe is provided in the middle of a refrigerant pipe connected to the compressor via a base. In this case, an engine-driving heat is formed in the mouthpiece by forming an expanded guide tube portion extending toward the metal bellows tube and forming a gap between the inner surface of the guide tube portion and the outer peripheral surface of the vibration absorbing tube. Refrigerant piping structure of pump device. 2. A refrigerant piping structure for an engine-driven heat pump device according to claim 1, wherein an inner surface of the base, which is continuous with the guide cylinder, is in close contact with an outer peripheral surface of the vibration absorbing tube. .