JP3213826B2 - Check valve and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a check valve applicable to various uses, such as for preventing a backflow of a refrigerant, in a refrigerant circuit of various refrigeration and cooling / heating devices, and a method of manufacturing the same.

[0002]

2. Description of the Related Art In a refrigerant circuit of a refrigeration / cooling / heating apparatus, for example, when a refrigerant flow path is formed at the time of switching a cycle of a heat pump cooling / heating apparatus, or in order to prevent backflow, or when a compressor of various refrigeration equipment is stopped, a rotary compression method is used. When a compressor is used, a check valve is provided at an appropriate position in the refrigerant circuit to prevent high-pressure gas from flowing back together with oil from the compressor.

Such a check valve is a plate or spherical check valve, a seat for receiving the check valve, and a holder for preventing the check valve from popping out of the copper pipe joint in terms of space and cost. Inserting a check valve assembly consisting of: and fixing it by caulking into the annular groove from the outer periphery of the copper pipe joint at a position corresponding to the annular groove formed on the outer periphery of the seat to manufacture a set of check valves Has been done.

In this caulking operation, a check valve assembly is inserted from one side opening of the copper pipe joint and pushed into the pipe by a predetermined length by a positioning stopper.
A checker is inserted to position the check valve assembly in the copper fitting, and is clamped and fixed at a predetermined position with the stopper end as a reference position. Next, a pressing tool that rotatably supports a roll piece having a V-shaped cross section at one end of the outer periphery of the copper pipe corresponding to the annular groove formed on the outer periphery of the seat of the check valve assembly and a V-shaped cross section at the other side. Place. Hold the outer circumference of one side of the copper pipe joint with a chuck, rotate the copper pipe joint to the center line of the pipe, move the pusher closer to the outer circumference of the copper pipe joint by rotating the cam, etc., and gradually move the roll piece to the outer circumference of the copper pipe joint. I will push it. As a result, the entire periphery of the portion where the roll piece on the outer periphery of the copper pipe joint is pressed is pressed into the annular groove formed on the outer periphery of the sheet, and the swaging is completed when the pusher is pushed in a predetermined length by rotation of the cam.

[0005]

In the caulking method described above, since the copper pipe joint is rotated and the roll piece is applied to the entire circumference, the entire outer circumference of the pipe is caulked, and the entire circumference of the pipe is set in the annular groove on the outer circumference of the sheet. Although there is an advantage that there is no gap because the pipe material enters, there is a check valve assembly that rotates with the copper pipe joint because the copper pipe joint is rotating, and a check valve that is inserted into the pipe and This causes rubbing due to frictional contact with the tip end surface of the fixed holding tool that holds the pressing member. For this reason, the distal end of the valve assembly may be damaged, and it is necessary to take measures such as designing without a projection so as not to damage the valve assembly.

Further, when rotating the copper pipe joint, rotation about the center axis of the copper pipe joint hand is not always performed accurately, and eccentric rotation may be performed.
At that time, the caulking was offset, and the caulking in the caulking was concentrated at one place, so that appropriate caulking could not be performed. Also, the copper tube does not rotate eccentrically
As well, if it is a state <br/> sheet periphery portion which is an internal component is eccentric, offset would occur caulking.

Further, the annular groove formed on the outer peripheral surface of the seat is
Since a V-shaped cross-section groove is usually used, the gripping force of the material of the tube that has entered the V-shaped cross-section groove by caulking is small,
When a large pressure is applied to the check valve, the check valve may escape in the reverse pressure direction. In particular, in a check valve body using a flat valve, since the flat valve and the holder are not in contact with each other, it is difficult to caulk while positioning the axis by the caulking method using a roll piece. Further, since the entire circumference of the pipe is uniformly caulked, the thickness of the caulked portion is also uniform, and the entire circumference of the caulked portion may be broken due to vibration or the like.

In addition, caulking by a roll top requires a lot of time since the caulking operation is performed while rotating the copper pipe joint many times, and thus has a disadvantage in that the working efficiency and the production efficiency are poor.

Therefore, the present invention can securely caulk the valve assembly without causing damage due to rubbing, does not cause the check valve assembly to come off, and does not cause cracks in the pipe. Moreover, it is an object of the present invention to provide a check valve in which a check valve assembly is fixed in a copper pipe joint by caulking means having good production efficiency, and a method of manufacturing the check valve.

[0010]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention is directed to a check valve assembly having a seat fitted in a pipe and a valve body with respect to an annular groove having a concave cross section formed on the outer periphery of the seat. A plurality of caulking pieces whose inner circumferences are arc-shaped are pressed from the outer circumference of the pipe and integrated with the pipe to form a check valve, with a non-caulking part between adjacent caulking parts by the caulking piece. In addition, a check valve assembly having a seat and a valve body is fitted into a pipe, and a plurality of caulking pieces having an arcuate inner surface are piped into an annular groove having a concave cross section formed on the outer periphery of the seat. The caulking is completed by pressing from the outer periphery and caulking is finished with a gap between adjacent caulking pieces, so that the valve assembly can be securely caulked without causing damage due to rubbing. Do not cause the valve assembly to come off. And it does not cause cracking in the tube, yet is obtained by producing efficient check valve and its manufacturing method.

[0011]

According to the present invention, as described above, the annular groove formed in the outer periphery of the seat of the check valve assembly fitted in the pipe is formed by a plurality of caulking pieces pressed from the outer circumference of the pipe. The material enters and is instantly swaged into a firmly fixed state. In the manufactured check valve, a caulking residual portion is generated between adjacent caulking portions, but also at this portion, the material of the pipe enters the annular groove on the outer periphery of the seat due to the influence of the adjacent caulking portion, and the groove is formed. Since the side wall of the concave portion of the groove is in close contact with the material of the tube, no fluid leakage occurs. Also,
The caulking remainder also serves to reinforce the tube.

[0012]

An embodiment of the present invention will be described with reference to the drawings. As shown in FIG.
A check valve assembly 5 including a plate-shaped valve body 1, a seat 3 having an opening 2 opened and closed by the valve body 1, and a holder 4 for restricting the movement of the valve body 1 is placed in a copper pipe joint 6. It is constituted by closing and fixing. The seat 3 is a leg 7 of the holder 4.
In addition to having a fitting groove 10 for fitting and fixing the bent portion 8 at the end of the outer peripheral portion 11, an annular groove 12 having a concave cross section is formed in the outer periphery 11. In the upper part of the valve body, which is the fully open position 1 ', the lower end of the claw-shaped stopper 13 projecting downward regulates the upward movement range of the valve body 1. FIG.
As shown in (a), even if the valve body 1 is pushed up obliquely, the valve body 1 is restricted by the stopper 13 and the leg 7 of the holder 4 and returns to the normal position.

The holder 4 is made of an elastic plate material, and the leg 7 of the holder 4 has a gap A between the holder 4 and the copper pipe joint 6 as shown in FIG. In addition, since the sheet is guided from the outside and the inside is also guided by the outer diameter portion of the sheet, even if the opening angle of the leg 7 of the holder 4 is incorrect before the assembly of the holder 4, it is forcibly performed. It has a prescribed shape and can guide the stable vertical movement of the valve body 1. The bent portion 8 at the tip of the leg 7 of the holder 4 is held by the fitting groove 10 even in the case of a shocking flow in the valve opening direction.

When fixing the check valve assembly 5 in the copper pipe joint 6, as shown in FIG. 3, the check valve assembly 5 is inserted through a lower end opening of the copper pipe joint 6, and then, is inserted into the upper end. A positioning stopper 16 having a positioning fitting portion 15 that can be fitted to the inner periphery of the copper pipe joint 6 is set up at the portion, and this positioning fitting portion 15 is fitted into the copper pipe joint 6 with the check valve assembly 5 to stand up. I do. Thereafter, a presser 18 having a press-fitting portion 17 that can be inserted into the copper pipe joint from above is fitted into the copper pipe joint, and the weight of the presser 18 or another pressing force is applied.
Below the upper end of the check valve assembly 5, that is, the positioning stopper 1
Press on the 6 side.

As shown in FIG. 4, three check valves 9 are set at the height of the outer peripheral surface of the copper pipe joint 6 where the annular groove 12 of the inner seat 3 is located. A swaging piece 20 is horizontally movably arranged, and three swaging pieces 2 are pressed by pressing means such as hydraulic pressure (not shown).
Reference numeral 0 approaches and comes into contact with the outer periphery of the copper pipe joint 6 while being aligned with the central axis of the copper pipe joint 6. When the caulking piece is further pressed, the outer circumference of the tube is crushed, and the inner circumference enters into the annular groove of the sheet 3.

The pressing is stopped when a predetermined amount is pushed by adjusting the pressing force such as the hydraulic pressure of the pressing means of the swaging piece 20, but at this time, there is a gap t between the three swaging pieces, so that the copper pipe joint As shown in FIGS. 5 and 6,
Non-caulked non-caulked portions 21 are formed.
When the caulking operation is completed, the caulking piece 20 returns to the original position, the holding member 18 is pulled out, and the check valve 9 in which the check valve assembly 5 and the copper pipe joint are integrated is pulled out from the positioning stopper 16.

The swaged portion of the check valve 9 manufactured as described above has a swaged portion 22 and a non-swaged portion 21 as shown in FIG.
While the tube material 23 has penetrated as far as possible into the annular groove 12, the non-caulked portion 21 does not penetrate as far as possible, and has a gap 24.

However, due to the influence of the adjacent caulking portion 22, there is provided a fitting portion 25 which enters into the annular groove 12, whereby the upper and lower end walls 26, 27 of the annular groove 12, as shown in FIG. The overlapping portion 28 is formed so as to be fitted while being in contact therewith. The overlapping portion 28 that fits in contact with the end walls 26 and 27 is smaller than that in the caulked portion, so that a sealing action is performed at this portion. Further, the annular groove 12 has a concave cross section, and the upper and lower end walls 26, 2
7, the overlapping portion 28 at this end wall portion is in a direction perpendicular to the axis, so that even if a large force is applied to the check valve, it does not come off from the caulked portion.

In the above embodiment, an example in which three caulking pieces are used has been described. However, if the number is two or more, an appropriate number can be selected. This caulking method is not limited to a check valve, and can be widely applied to a method of caulking a valve element fitted into a pipe such as an expansion valve from the outer periphery and integrating the valve body with the pipe.

[0020]

Since the present invention is constructed and operated as described above, it does not cause friction between the holding member and the check valve assembly as in the case of caulking using a conventional roll piece, thus preventing the check valve. Valve damage can be avoided. Also, since there is no deviation in swaging, centering is automatically performed,
Reliable staking can be performed, and cracking of the pipe due to over-staking can be prevented.

Further, since the non-caulked portion is formed between the adjacent caulked portions, the non-caulked portion serves as a reinforcing portion of the pipe, and it is possible to prevent the pipe from being broken or broken. In addition, since the caulking piece is only pressed from the outer periphery of the tube, it can be manufactured very quickly and the production efficiency can be improved. In addition, since it is caulked in the annular groove having a concave cross section, the fixing strength is improved, and the check valve assembly does not come off even when high pressure is applied.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an embodiment of a check valve according to the present invention.

FIG. 2A is a longitudinal sectional view of another embodiment of the check valve according to the present invention, and FIG. 2B is a plan view of the embodiment of the check valve.

FIG. 3 is a longitudinal sectional view showing a state when a check valve according to the present invention is manufactured.

FIG. 4 is a partial sectional view taken along line AA of FIG. 3;

FIG. 5 is a cross-sectional view of an embodiment of the check valve according to the present invention.

FIG. 6 is a partially enlarged view of FIG. 5;

FIG. 7 is a partial sectional view taken along the line BB of FIG. 5;

FIG. 8 is an external view of a caulked portion of the embodiment of the check valve according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Valve body 3 Seat 4 Holder 5 Check valve assembly 6 Copper pipe joint 9 Check valve 12 Annular groove 16 Positioning stopper 18 Pressing tool 20 Caulking piece 21 Non-caulking part 22 Caulking part 24 Gap 25 Fitting part 28 Overlapping part

──────────────────────────────────────────────────続 き Continuation of the front page (56) References Japanese Utility Model Sho 58-30078 (JP, U) Japanese Utility Model Sho 56-30665 (JP, U) Japanese Utility Model Hei 3-66987 (JP, U) Japanese Utility Model Sho 60- 5159 (JP, Y2) (58) Fields investigated (Int. Cl. ⁷ , DB name) F16K 15/00-15/20 B21D 39/04

Claims (2)

(57) [Claims] 1. A check valve assembly having a seat and a valve body fitted in a pipe is connected to a check groove assembly having a concave cross-section formed in the outer periphery of the seat by a plurality of caulking pieces having an inner circumference in an arc shape. The check valve is integrated with the pipe by pressing against the outer circumference,
A check valve having a non-caulking part between adjacent caulking parts by said caulking piece. 2. A check valve assembly having a seat and a valve body is fitted in a pipe, and a plurality of caulking pieces having an arcuate inner circumference are formed in a circular groove formed in the outer periphery of the seat. A method for manufacturing a check valve, comprising: crimping by pressing from the outer periphery, and terminating the crimping in a state where there is a gap between adjacent crimping pieces.