JPH10159804A - Accumulator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent any rust from taking place in the jointing part of a shell to deteriorate its fixing attachment by forming a deformed part on the spirally fitting surface of the screw part between a cylinder and an end cover. SOLUTION: An accumulator 1 is composed of a shell 2 in whose inner peripheral surface 15 a hollow chamber 3 is formed and a piston 6 fitted freely slidably on the inner peripheral surface 15. This shell 2 is constituted in such a way that an end cover 11 in which the second screw part 12 is provided is screw jointed to the first screw part 10 formed on the external peripheral surface 9 of the opening part 8 of a cylinder 7 having its bottom and cylindrical shape. And also, the shell 2 is subjected to such surface treatment as plating, etc., so as to fit the piston 6 in the cylinder 7 and additionally the second screw part 12 of the end cover 11 is tightened to the first screw part 10 of the cylinder 7 up to its terminal end while making screw jointing the second screw part 12 of the end cover 11 to the first screw part 10 of the cylinder 7. Next, a thin wall part 13 is given hit scars by means of a chisel, a deformed part 17 is formed on mutually screwed surface 14 so as to engagingly lock the cylinder 7 to the end cover 11. Since this hit scar is formed in a small size, plating may not be peeled off at the time of making hit scars.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an accumulator for adjusting pressure by introducing fluctuations in fluid pressure into a gas chamber. In particular, it relates to a piston type accumulator.

[0002]

2. Description of the Related Art An accumulator shown in FIG. 5 exists as a prior art according to the present invention.

FIG. 5 is a sectional view of a main part of the accumulator 100. In FIG. 5, the accumulator 100
Is provided with a piston 103 slidably fitted on the inner peripheral surface 109 of a cylindrical shell 110. On the outer peripheral surface 103a of the piston 103, two O-rings 104 and 105 are fitted in respective grooves, and
Is sealed with the inner peripheral surface 109.

[0004] The empty space of the shell 110 is divided by a piston 103 into a gas filling chamber 107 and a liquid chamber 108. The gas filling chamber 107 is provided with a gas valve 111, and the liquid chamber 108 is provided with a liquid port (not shown) so as to be connectable to piping.

[0005] The shell 110 has a screw formed on the outer peripheral surface on the opening side of the cylinder 101 having a bottom and a screw formed on the inner peripheral surface of the end cover 102 having a bottom, and an empty space is formed therein. Has formed. And this cylinder 101
Both are fixed by penetrating split pins 112 so that the screw engagement between the and the end cover 102 is not loosened.

The fixing by the pin 112
01 and the end cover 102 are screwed into
And a split pin or pin 112 is driven into the pin hole 113 to be fixed.

Incidentally, the shell 110 is subjected to a plating process because it is exposed to an atmosphere of moisture or salt.
However, since the pin hole 113 cannot be machined until after the cylinder 101 and the end cover 102 are assembled, the pin hole 113 cannot be plated and causes rust. In particular, when rust occurs on the pin 112 and the pin hole 113, the pin 112
The cylinder 101 and the end cover 102 loosen from each other or are broken, and finally, a breakdown or an accident is caused by the high pressure inside.

FIG. 6 shows another prior art accumulator 1.
It is sectional drawing of 00.

FIG. 6 differs from FIG. 5 in that the open end 114 of the end cover 102 is formed to be thin. Then, the annular convex portion 11 of the cylinder 101
The end cover 102 is fixed to the cylinder 101 by caulking the opening end 114 at 5. Reference numeral 106 denotes a fluid port that communicates with the liquid chamber 108. Other configurations are similar to those in FIG.

An end cover 102 is attached to the cylinder 101.
In the caulking method of fixing the end, the thin open end 114 of the end cover 102 is caulked over the entire surface, so that the plating is peeled off.

As a result, rust occurs at the opening end 114. Then, since the opening end 114 is formed to be thin due to caulking, the opening end 114 is broken by rust, and the cylinder 101 and the end cover 1 are broken.
02 is loose and causes a failure or accident. In addition, the precision that the opening end 114 is processed to be thin is required, and the cost increases.

[0012]

The position of the accumulator shown in FIG. 5 is determined by tightening and fixing the thread portions of the cylinder 101 and the end cover 102 in accordance with the processing accuracy. At the stage where this position is determined, the pin hole 113 must be processed, and the pin 112 must be driven into the pin hole 113 to be fixed. For this reason, since the pin hole 113 cannot be plated, rust is generated from the pin hole 113,
The failure of the accumulator is caused by the fixing failure caused by the pin 112.

The accumulator shown in FIG. 6 is formed by a cylinder 101 by caulking after plating.
And the end cover 102 are fixed, but the entire periphery of the swaged open end 114 is thin, and the thin open end 114 causes peeling of plating due to swaging. When rust occurs on the opening end 114, the opening end 114 is easily broken.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and an object of the present invention is to prevent rust from being generated at a fixing portion of a joint portion of a shell and causing a fixing problem. is there. Another object of the present invention is to allow the cylinder and the end cover to be easily locked and fixed after the cylinder and the end cover are tightened and fixed in accordance with their accuracy.

[0015]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and the technical means thereof is configured as follows. That is, claim 1 has a cylinder 7 which has a bottomed cylindrical shape and has a first threaded portion on the peripheral surface of the opening and which has been subjected to rust prevention treatment, and a second threaded portion which is screwed into the first threaded portion of the cylinder. A shell 2, which forms an empty space in the inner peripheral surface by screwing with the end cover 11 which has been subjected to rust prevention treatment, and is slidably fitted to the inner peripheral surface of the shell to partition one of the empty spaces into a gas chamber. It has a piston 6 for partitioning the other into an operating chamber, and forms a thin portion 13 on the outer peripheral side of a screwing surface 14 between the first screw portion and the second screw portion of the shell, and from the thin portion to the first screw portion and the second screw portion. The cylinder 7 and the end cover 11 are locked by forming a deformed portion 17 on a screwing surface with a screw portion.

Further, a member having a screw portion on the outer peripheral side of the screwing surface 14 of the first screw portion and the second screw portion of the shell 2 has a through hole 16 reaching the screwing surface 14. , Through hole 1
The cylinder 7 and the end cover 11 are locked by forming a deformed portion 17 in a threaded portion in 6.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An accumulator according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a half sectional view of an accumulator according to an embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes a piston type accumulator. The accumulator 1 includes a cylindrical shell 2 in which an empty space 3 is formed in an inner peripheral surface 15 and a piston 6 slidably fitted on the inner peripheral surface 15.

The shell 2 has a bottomed cylindrical cylinder 7.
And a bottomed cylindrical end cover 11 provided with a second screw portion 12 which is screwed to a first screw portion 10 formed on an outer peripheral surface 9 of the opening 8 of the cylinder 7 by screwing them together. The vacant space 3 is formed in the peripheral surface 15.

The cylinder 7 and the end cover 11 are
If only the screwing is performed, the screwing surface 14 is loosened, and the pressure fluid in the empty chamber 3 flows out. Therefore, a thin portion 13 is formed on the end cover 11 located on the outer periphery of the screwing surface 14 of the screw portions 10 and 12 between the cylinder 7 and the end cover 11, and the thin portion 13 is stamped and deformed into the screwing surface 14. Forming a part 17, the screwing surface 1 of the cylinder 7 and the end cover 11
4 is locked. The thin portion 13 can be made thin by forming a hole or a groove in the end cover 11.

FIG. 2 shows an enlarged cross section.

In FIG. 2, the first screw portion 1 of the cylinder 7
A thin portion 13 is formed on the bottom surface of the machined hole in the end cover 11 located outside the mutually screwed surface 14 of the 0 and the second screw portion 12 of the end cover 11. Then, the recess 18 is formed from the outer surface of the thin-walled portion 13 with the slug 30, so that the screwing surface 14 between the first screw portion 10 and the second screw portion 12 is formed.
The cylinder 7 and the end cover 11 are locked so as not to be loosened.

Since the shell 2 comes into contact with moisture and salt in the atmosphere, a surface treatment such as plating is performed for each component. Thereafter, the piston 6 is fitted into the cylinder 7, and the second threaded portion 12 of the end cover 11 is screwed to the first threaded portion 10 of the cylinder 7 and tightened to the final end. Reference numeral 19 denotes a stopper provided on the cylinder 7 for fixing the tightening end of the end cover 11.

Next, an indentation is made on the thin-walled portion 13 with a flap 30.
A deformed portion 17 is formed on each screwing surface 14 to lock the cylinder 7 and the end cover 11. Since the indentations are formed small, the plating does not peel off during the indentations. Even if the plating is peeled off, the strength is not reduced from the rusted portion because of the small area.

FIG. 3 is a sectional view of an accumulator according to another embodiment of the present invention.

FIG. 3 is different from FIG. 1 in that the end cover 11 has a through-hole 16 such that the thin portion 13 is eliminated.
Is formed, and the deformed portion 17 is indented from the through hole 16 to the first threaded portion 10 of the cylinder 7 by the slack 30. The screwing surfaces 14 are locked to each other by the deformed portion 17.

FIG. 4 is an enlarged view of the deformed portion 17.
In FIG. 4, a deformed portion 17 is formed in the first threaded portion 10 from the through hole 16 with a ridge 30. Then, if necessary, a rubber stopper 20 is fitted into the through hole 16.

The deformed portion 1 is formed in the first screw portion 10 by the indentation.
Even if 7 is formed, since the amount of deformation is small, the plating does not peel off. Even if it occurs, the strength is not reduced due to rust because of the small amount of deformed portion 17.

In FIG. 3, the other components are the same as those indicated by the reference numerals in FIG.
The number of the thin portions 13 is not limited to one, but may be plural in the circumferential direction. Further, the number of through holes 16 is not limited to one, but may be plural in the circumferential direction. Further, reference numeral 21 denotes an O-ring that seals between fittings, and reference numeral 22 denotes a fluid port through which fluid flows to the working chamber 4 of the accumulator. Also, when replacing the piston, if the cylinder 7 and the end cover 11 are strongly reversed, the deformed portion 17 becomes close to the state before the deformation and can be disassembled. Further, even if the deformed portion 17 is deleted, it can be disassembled. Then, if reconfigured in the same manner as in the present invention, the cylinder 7 and the end cover 11 can be locked again.

[0031]

According to the accumulator of the present invention, since the deformed portion is formed on the threaded surface of the threaded portion of the cylinder and the end cover, the cylinder and the end cover are locked by the threaded surface,
Looseness of the threaded surface is effectively prevented. At the same time, the screwing surface of the screw portion is locked by the small deformed portion, so that rust is prevented from being generated in the deformed portion. Even if rust is generated, the area of the rust portion is small and the strength of the deformed portion is not reduced by the rust, so that the accumulator does not fail. Also, at the same time as forming the thin part,
Since the indentation work of the deformed portion is also very easy, the engagement between the cylinder and the end cover can be effectively achieved. Furthermore, if you want to disassemble the cylinder and end cover from necessity,
If the deformed part is slightly removed, it can be easily disassembled. Then, if the processed portion is subjected to rust prevention treatment, re-assembled, and then a deformed portion is formed, the two can be easily locked.

[Brief description of the drawings]

FIG. 1 is a half sectional view of an accumulator according to an embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view showing a deformed portion of the screwing surface of FIG.

FIG. 3 is a half sectional view of an accumulator according to another embodiment of the present invention.

FIG. 4 is an enlarged cross-sectional view showing a deformed portion of the screw surface of FIG. 3;

FIG. 5 is a sectional view of a main part of a conventional accumulator.

FIG. 6 is a sectional view of another conventional accumulator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Accumulator 2 ... Shell 3 ... Empty chamber 4 ... Working chamber 5 ... Gas chamber 6 ... Piston 7 ... Cylinder 8 ... Opening 9 ... Outer peripheral surface 10 ... 1st screw part 11 ... ... End cover 12... Second screw portion 13... Thin portion 14... Screwing surface 15... Inner peripheral surface 16... Through hole 17. O-ring 22 Fluid port 30 Fragment 100 Accumulator 101 Cylinder 102 End cover 103 Piston 103a Outer peripheral surface 104, 105 O-ring 106 Fluid port 107 Gas filled chamber 108 Liquid chamber 109 Inner peripheral surface 110 Shell 111 Gas valve 112 Pin 113 Pin hole 114 Open end 115 Annular convex

Claims (2)

[Claims] 1. A rust-proof cylinder (7) having a bottomed cylindrical shape and having a first threaded portion (10) on a peripheral surface of an opening (8), and a first threaded portion of the cylinder (7). A shell (2) that is screwed with a rust-proofed end cover (11) having a second screw portion (12) that is screwed into (10) to form an empty space (3) in the inner peripheral surface (15). ), Said shell (2)
Slidably fitted to the inner peripheral surface (15) of the vacant chamber (3)
One is partitioned into a gas chamber (5) and the other is a working chamber (4).
A thin portion (13) on an outer peripheral side of a screwing surface (14) of the first screw portion (10) and the second screw portion (12) of the shell (2). And forming a deformed part (17) from the thin part (13) on the screwing surface (14) of the first screw part (10) and the second screw part (12) to form the cylinder ( 7) The accumulator, wherein the end cover (11) is locked with the end cover (11). 2. The first threaded portion (1) of the shell (2).
0) and the screwing surface (14) of the second screw portion (12).
A member having the screw portion (12 or 10) on the outer peripheral side of the member has a through hole (16) reaching the screwing surface (14),
The accumulator according to claim 1, wherein a deformed portion (17) is formed in the screw portion (10 or 12) in the through hole (16) to lock the cylinder (7) and the end cover (11).