KR100519624B1 - Length Adjustable Gas Spring - Google Patents

Abstract

The present invention relates to a length regulating gas spring, an outer cylinder, a cylinder embedded in the interior of the outer cylinder, a gas moving passage tube embedded in the cylinder, and a piston unit integrally formed with a piston unit and a piston rod unit. As a structure, the outer diameter surface of the cylinder is a cylindrical superhard mold to achieve the roundness and straightness of the cylinder.The spindle support of the outer cylinder allows the spindle support to be fixed between the bend of the lower end of the outer cylinder and the protruding protrusion above the bent portion. By compressing and coating the heat-shrinkable tube on the outer diameter surfaces of the outer and outer cylinders, the present invention relates to a product innovation that can produce a product by applying various colors to the outer diameter surface, which was only available in a single color, and a length-controlled gas spring that reduces manufacturing costs.

Description

 Length Adjustable Gas Spring

In order to achieve the object of the present invention, in the present invention, the upper end of the cylinder has a push bar for assembling the gas moving passage pipe and a valve body for assembling the push bar and a lower part of the gas moving passage tube to the inner side of the piston rod through the center of the piston. It has a one-piece piston structure with a circular gas flow passage hole in the center for insertion.The roundness, straightness, and surface of the cylinder's outer diameter surface are made by passing the outer diameter surface of the cylinder through the outer diameter surface with a cylindrical superhard mold. It improves roughness, and the spindle support of the outer cylinder has a bent portion rounded inwardly with the lower end of the outer cylinder and at least two inwardly projecting projections on the upper portion thereof, so that the spindle support is not welded between the bent portion of the lower cylinder and the projection. It is fixed, and cylinder and piston rod part As fast cylinder structure that implement various colors by compression bonding of the heat-shrinkable tube covering the outer surface of the outer tube, the invention provided an innovative electrical product innovation, reduce manufacturing costs and productivity improve performance.

Conventional length control gas spring is a double cylinder structure consisting of the inner cylinder (44a) and the outer cylinder (10a) is composed of many parts inside the outer cylinder (10a), the piston (80a) is made of synthetic resin or metal metal rod The piston rod 30a made of a metal round rod is a piston structure that is coupled to the piston rod 30a by riveting operations to perform a surface polishing process to remove pin holes, fine stamp marks, etc. on the surface of the metal round rod. The plating is prevented by corrosion, and the piston 80a and the piston rod 30a are mutually coupled by a riveting process, and the upper inclined portion 12a of the outer cylinder 10a is formed by compression of the shaft mold based on the power press. The outer diameter surface of the outer cylinder 10a except the inclined portion 12a is bent in the transverse direction by the compression force of the shaft mold, and the outer diameter is Since this problem is the irregular outer surface of the outer cylinder (10a) outer surface roundness and straightness and complement and improve the outer cylinder (10a) for grinding by the abrasive grinding process is to prevent oxidation by chromium plating. The spindle support 50a is welded to the bottom of the outer cylinder 20a based on a welding operation and is surface treated by powder coating or electrodeposition coating to prevent oxidation of the outer diameter surface of the outer cylinder.

As described above, the polishing work on the surface of the conventional gas spring parts and the surface treatment work by chromium plating and painting may cause environmental pollution and serious damage to the human body of the worker, and require a complicated and highly functional polishing process. The process of plating and painting requires precision technicians and requires a lot of work time due to complicated and diverse work processes, which increases the cost of manufacturing parts.

Length adjustment gas spring is a very important core product to adjust the seat height of the chair. Conventionally, a double cylinder structure consisting of an outer cylinder (10a) and an inner cylinder (44a) is composed of the assembly of many ultra-precision parts, attached Referring to the drawings as follows.

Figure 1 is a longitudinal cross-sectional view showing a conventional regulating gas spring, Figure 2 is a cross-sectional view showing a conventional valve assembly structure and gas opening and closing pins, Figure 3 is an enlarged cross-sectional view showing a piston assembly in an operating state in a conventional length regulating gas spring. to be.

As shown in FIG. 1, the conventional length adjusting gas spring has a rod-shaped outer cylinder 10a and a piston rod 30a mounted below the outer cylinder 20a in which the outer cylinder is inserted, and the surface of the outer cylinder 10a is After the polishing process is chrome plated, the push rod (14a) is fixed to the upper side of the outer cylinder (10a) by the push support 16a, the lower portion of the push rod is arranged to abut the gas opening and closing pin (100a). . The gas opening and closing pin (100a) is installed to move up and down in the valve assembly (40a) assembled in the outer cylinder (10a),

The spindle support 50a is fixed to the outer cylinder 20a by a welding process under the outer cylinder, and the piston rod 30a is fixed through the spindle support 50a. The surface of the outer cylinder is powder coated or electrodeposited. To prevent oxidation, the outer cylinder (10a) is the upper portion of the tapered inclined portion (12a). An inner cylinder 44a is disposed in the outer cylinder 10a, and a thrust bearing 60a and an anti-vibration rubber 62a are mounted on the spindle support 50a. The lower part of the piston rod 30a is fixed to the spindle support 50a by a clip 70a so as to be coupled to or separated from the spindle support 50a. The surface of the piston rod 30a is oxidized by chromium plating after polishing. Prevented.

2 is a sectional view showing a conventional valve assembly 40a. The valve assembly 40a has a cylindrical shape as a whole, and forms an inner circumferential hole 41a into which the gas opening and closing pin 100a is inserted, and an O-ring is inserted in the outer O-ring groove 43a to maintain airtightness. It is

The inner center of the valve assembly 40a is a space 46a for distributing gas, and at least two O-rings 45a are disposed in the space 46a for airtightness. In addition, the space portion 46a is provided with an inner holder 47a to maintain the gap between the O-ring 45a and to smoothly operate the gas opening and closing pin 100a. One side of the inner holder 47a is connected with the gas passage hole 42a so that a minute hole is drilled. In FIG. 1, the slide member 52a is disposed between the outer cylinder 10a and the outer cylinder 20a to be external. The cylinder 10a was made to allow slide movement.

Referring to Figure 3 with respect to the piston (80a) installed on the upper side of the piston rod (30a), the piston (80a) and the piston rod (30a) is separated from each other, the piston rod (30a) is a metal rod It is manufactured by a machining process, a surface polishing process, and a chromium plating process, and the piston 80a is inserted into the upper end of the piston rod 30a and then fixed to the upper end of the piston rod 30a by a riveting operation. In order to maintain gas tightness inside and outside, several O-rings 82a are inserted. A rod guide 83a is assembled at the inner lower portion of the outer cylinder 10a, and a rod seal 84a is assembled at the upper side of the rod guide to maintain gas tightness of the outer cylinder 10a.

A ring 88a, a two-stage washer 85a, and the like are used to engage the piston 80a, and the two-stage washer 85a supports the lower end of the piston 80a.

The arrow direction in FIG. 3 shows a state in which gas moves from the chamber chamber C to the chamber chamber A. As shown in FIG.

As shown in FIG. 1, when the push rod 14a installed at the top of the outer cylinder 10a is pressed, the push rod 14a presses the gas opening and closing pin 100a. The small diameter portion 102a located in the middle of the fin 100a is downward to open the space portion 46a and the chamber chamber A. Since the space portion 46a communicates with the gas passage hole 42a, the gas in the chamber chamber C temporarily moves to the chamber chamber A side. The chamber (C) has a higher gas pressure than the chamber (A) side, so the piston (80a) pushes the piston (80a) smoothly, and the lower end of the piston rod (30a) has a spindle support (a) of the outer cylinder (20a). Since it is fixed to 50a), the outer cylinder 10a eventually rises by reaction.

When the pressing force of the push rod 14a is removed, the small diameter portion 102a of the gas opening and closing pin 100a is raised to close the space portion 46a and the chamber chamber A, so that the outer cylinder 10a is lifted up. Stop.

The present invention is a single-cylinder structure consisting of one cylinder 30 by applying the gas flow passage pipe 70 to solve the above problems, to minimize the number of parts assembled in the cylinder 30, the piston integral 90 is composed of a piston portion 81 and the piston rod 91, integrally formed by metal casting or synthetic resin injection molding, the outer cylinder 120, the bent portion 123 and the inner protrusions toward the inner side of the lower end (120) The spindle support 130 is fixed without welding between 122 and the outer diameter surface 32 of the cylinder 30 is passed through the inner side of the cylindrical superhard mold, thereby improving accuracy of roundness, straightness and surface roughness. 30) and the outer diameter surfaces of the piston rod 91 and the outer cylinder 120 are heat shrinkable tubes (32-1, 95-1, 124-1) that can be various colors without conventional grinding, chrome plating and painting process Crimped) As by adjustable length having a fast cylinder 30 architecture implement different colors required by customers gas spring, product innovation course, that would make up the improved quality, reduce production costs and improve productivity purposes another object of the present invention.

In order to achieve the above object, the present invention relates to a length control gas spring, the outer cylinder, a cylinder embedded in the interior of the outer cylinder, and the gas flow passage tube is built in the cylinder, the piston portion, And the piston rod structure with integral piston rod structure, the outer diameter surface of the cylinder is a cylindrical ultra-hard mold to achieve the roundness and straightness of the cylinder, the spindle support of the outer cylinder between the bend of the lower end of the outer cylinder and the protrusion projected above the bent portion By compressing and coating the heat-shrinkable tube on the outer diameter surface of the cylinder, the piston rod part and the outer cylinder, the product innovation that can produce products by applying a variety of colors to the outer diameter surface that was possible only in a single color can be achieved. It relates to a regulating gas spring.

The present invention will be described with reference to the drawings.

Figure 1 is a longitudinal sectional view showing a conventional length regulating gas spring, Figure 2 is a sectional view showing a valve assembly in a conventional length regulating gas spring, Figure 3 is a sectional view showing a piston assembly in a conventional length regulating gas spring, Figure 4 Figure 5 is a longitudinal sectional view showing a length adjusting gas spring of the present invention, Figure 5 is a state in which the cylinder of the length adjusting gas spring of the present invention is raised, Figure 6 is a detailed view of the cylinder of the present invention, Figure 7 is a cylinder upper detail of the present invention Figure 8 is a detailed view of the push bar of the present invention, Figure 9 is a detailed view of the valve seal of the present invention, Figure 10 is a detailed view of the push support of the present invention, Figure 11 is a detailed view of the gas flow passage pipe of the present invention, Figure 12 Figure 13 is a detailed view of the piston unit of the present invention, Figure 13 is a detailed view of the piston unit of the piston unit incorporated in the cylinder of the present invention, Figure 14 is a detailed view of the outer cylinder of the present invention, Figure 15 shows another state diagram of the outer cylinder in the present invention. Cylinder 30, Inclined portion 31, outer diameter surface 32, adhesive layer 32-1, heat shrinkable tube 32-2, cylinder inner surface 33, boundary surface 34, end inner surface 35, inclined surface 36, Push bar 40, small diameter portion 41, inclined surface 42, large diameter portion 43, the central groove inner surface 44, the central groove 45, the gas movement hole 46, the push support 50 , Central through hole (51), central groove (52), outer groove (53), O-ring (54), valve seal (60), inner circumferential seal lip (61), corner seal lip (62), upper inner hole (63), center Groove 64, gas flow passage tube 70, gas flow passage 71, upper end portion 72, lower portion 73, metal bar 74, piston portion 81, inner step groove 82 ), Outer groove 83, O-ring 84, support member 85, inner groove 86, O-ring 87, the piston body 90, piston rod 91, central inner groove 92, Inner diameter surface 93, boundary surface 94, outer diameter surface 95, adhesive layer 95-1, heat shrinkable tube 95-2, lower portion 96, groove 97, gas movement hole 98 , Rod seal 100, metal core 101, rod guide 110, outer cylinder 120, inner protrusion 121, inner protrusion 122, bent portion ( 123, outer diameter surface 124, adhesive layer 124-1, heat shrinkable tube 124-2, outer surface white layer 124a, outer surface nitride diffusion layer 124b, inner surface surface 125, inner surface white Layer 125a, inner nitride diffusion layer 125b, spindle support 130, outer portion 131, central hole 132, slide member 140, anti-vibration rubber 150, clip 160, outer metal thickness (T), X chamber room (X), and Y chamber room (Y) are shown.

Looking at the structure, Figure 4 and Figure 5 is a longitudinal cross-sectional view showing a length control gas spring of the present invention,

The upper and lower portions of the cylindrical outer cylinder 120 is opened, and the upper structure is a single structure that is built up over the upper and inside of the outer cylinder 120 is moved up and down about the outer cylinder 120 to act as a piston and the upper portion is open The lower part is press-fitted and fixed to the inside of the cylindrical cylinder 30 having a through-hole formed in the center, and the upper edge of the outer cylinder 120, and serves to support the built-in cylinder 30 to move up and down smoothly. The slide member 140, the spindle support 130 is inserted into the open lower portion of the outer cylinder 120, the central support 132 is formed in the center and the interior of the cylinder 30, The cylinder 30 serves to fix when the cylinder moves up and down, and a central inner groove 92 (space) is formed so that the gas movement passage tube 70 can be moved, and a gas movement hole through which gas is moved on the upper side ( 68) A piston support 90, a push support 50 formed in the open upper inner side of the cylinder 30 and acting as a stopper, a groove is formed in the middle edge of the side, and a hole formed in the center thereof, and the push support 50 And a valve seal 60 made of an annular rubber and elastic body having a hole formed in the center of the cylinder 30 to prevent the gas inside the cylinder 30 from flowing out to the outside, and the push support 50 and the valve. The upper part is inserted into the central through hole of the seal 60 and protrudes outward from the upper part of the cylinder 30. The lower part has an arc shape and has a predetermined step, and an insertion groove is formed in the lower center, and an outer peripheral surface is formed on one side of the insertion groove. The push bar 40 made of a synthetic resin material having the gas moving hole 46 formed therein, and is inserted into and fixed to an insertion groove formed in the center of the middle part of the lower part of the push bar 40 and has a long shape and a metal bar therein. Interpolate) And a gas flow passage tube 70 made of synthetic resin or metal, which is inserted into the central inner groove 92 leading to the center of the piston body 90, and an open lower inner side of the cylinder 30. Is formed, the rod seal 100 of the rubber and elastic material, the rod guide 110 is formed on the lower side of the rod seal 100, and the cylinder which is provided on the upper portion of the spindle support (130) Anti-vibration rubber 150 to alleviate the impact of 30, and the piston body 90 passing through the lower central hole of the cylinder 30 and penetrated the central hole 132 of the lower spindle support 130 of the outer cylinder 120 It is a length adjustment gas spring structure consisting of a clip 160 to be fixed to the groove 97 of the lower portion (96).

6 and 7, the inclined portion 31 coupled to the upper plate of the chair, and the outer diameter surface of the cylinder 30 forming the outer surface of the cylinder 30, as shown in Figs. (32), the inner diameter of the lower one side of the cylinder 30 is inclined between the end inner surface 35 formed larger than the inner diameter of the cylinder inner surface 33, and the lower end inner surface 35 and the cylinder inner surface 33 In the center of the lower portion of the lower surface of the cylinder 34, the inclined surface 36 formed to bend at right angles to prevent the components formed on the inner surface of the cylinder 30 to escape to the outside Is formed of the through hole, the lower portion of the cylinder 30, the metal core 101 is installed on the interface 34, the rod seal 100 is formed by inserting the metal core 101, and the metal core The rod guide 110 formed between the 101 and the lowermost part of the cylinder is constituted. I can see that.

The metal core 101 is to prevent the rod seal 100 and the rod guide 110 from being moved into the cylinder due to the high-pressure gas pressure injected into the cylinder,

In the conventional length-controlled gas spring, the upper inclined portion 12a of the outer cylinder 10a is formed by compression by a vertical force of the shaft mold based on a power press operated up and down, and thus the outer diameter surface of the outer cylinder 10a is the shaft tube. Due to the compressive force of the mold, the outer diameter of the outer cylinder 10a is irregular and the outer diameter of the outer cylinder 10a is irregular, and the outer diameter and outer surface of the outer cylinder 10a are subjected to the abrasive grinding process. By grinding the surface of the outer diameter surface thinly through this, the roundness and straightness of the outer diameter surface of the outer cylinder 10a are corrected, and the entire outer surface of the outer surface is treated with chromium plating so as not to oxidize the grinding surface, and the outer diameter of the outer cylinder 10a In the process of chromium plating on the surface, pinholes and scratches on the rough surface and outer diameter surface caused by abrasive grinding on the outer diameter surface are It causes uneven density and uneven plating at the fine parts. Therefore, the rough surface roughness of the chromium plated outer diameter surface is treated with chrome plating, and the outer diameter surface is subjected to two to three puffing grinding processes. To maintain the illuminance

In the present invention, the outer diameter surface 32 of the cylinder 30, which is bent in the transverse direction in the process of forming the upper inclined portion 31 by the compression by the vertical force of the shaft mold based on the power press, is a cylindrical cemented carbide formed of special carbide. As a mold, the inside has a cylindrical inner through-hole having an accurate roundness, and the inner diameter of the inner through is smaller than the outer diameter of the pipe in the state before the formation of the upper inclined portion 31 and at the same time the outer diameter of the cylinder 30 to be achieved. It is formed in the same dimensions and the cylindrical mold length is 10% to 40% of the total length of the cylinder 30, the appropriate length is 20% of the total length is appropriate. The inner surface roughness of the inner cavity of the cemented carbide mold is so high that it maintains a high gloss like the mirror surface when viewed in natural light, and as the cemented carbide, the entire outer diameter surface 32 of the cylinder 30 is used to By passing through the roundness of the outer diameter 32 of the cylinder 30 is formed on the basis of the cylindrical roundness of the inner hole of the cemented carbide mold, the exact straightness of the cylinder 30 is formed on the basis of the appropriate cemented carbide length The surface roughness of the outer diameter surface 32 of the cylinder 30 is greatly improved based on the high inner roughness of the inner cavity of the cemented carbide die, and at the same time, the structure of the outer diameter surface 32 of the cylinder 30 is uniformly dense. Passing the cylinder 30 into the superhard mold formed of a special steel to achieve the outer diameter surface 32 of the cylinder 30 having accurate roundness, straightness and improved surface roughness.

A synthetic resin-based adhesive is applied to the entire outer diameter surface 32 of the cylinder 30 to form an adhesive layer 32-1 of a thin film, and the entire outer portion of the adhesive layer 32-1 is made of engineering plastic. The outer diameter surface 32 of the entire cylinder 30 and the adhesive layer 32-1 of the entire cylinder 30 are applied by applying appropriate heat to the heat shrinkable tube 32-2 formed of a thin film having excellent corrosion resistance and various colors. Press-coating can provide various colors to prevent oxidation and to meet customer requirements. Heat-shrinkable tube is a rigid thin tube made of engineering plastic with high strength, abrasion resistance, oil resistance, oxidation resistance, etc., and has a characteristic of shrinking about 10% to 50% when an appropriate temperature is applied to the tube. -2) is appropriate for the thickness of 0.01mm ~ 0.5mm.

Shrinkage is performed by passing heat, steam, or oven within a temperature range that does not affect rubber-sealed seals, O-rings, etc., used in length-controlled gas springs, and an appropriate temperature range in which the heat-shrinkable tube shrinks. The tube is contracted to a certain thickness and adhered to the entire outer diameter surface 32 of the cylinder 30 to achieve perfect oxidation and various colors for the outer diameter surface 32 of the cylinder 30.

As shown in FIG. 8, the push bar 40 has a circular rod shape molded and injected from a synthetic resin material, and has a small diameter portion 41 forming an upper portion, and a lower diameter portion formed below the small diameter portion and having an arc toward the bottom thereof. A large diameter portion 43 having a predetermined step, an arc-shaped inclined surface 42 forming a boundary between the large diameter portion 43 and the small diameter portion 41, and the gas flow passage pipe ( The upper end of the 70 is inserted and bonded to the central groove 45 formed with a central groove inner surface 44 (space) from the lower portion of the large diameter portion 43 to one side of the upper central portion, and the inside of the central groove 45 It is formed to penetrate the central groove inner surface 44 and the arc-shaped inclined surface 42, the gas of the Y chamber chamber (Y) through the gas movement passage pipe 70 and the central groove (45) X chamber chamber (X) It can be seen that it consists of a gas moving hole 46 that serves as a guide to flow in the have.

As shown in FIG. 9, the valve seal 60 is a seal made of an annular rubber and an elastic body that is internally bonded to the push support 50.

The upper inner through-hole 63 formed in the upper portion, the lower portion of the central groove 64 of the circular space form of the inner diameter larger than the upper inner through-hole 63, and the inside of the small diameter portion 41 of the push bar 40 An inner circumferential surface seal lip 61 having at least one seal lip having a sealing function for preventing the gas inside the cylinder 30 from leaking out during up and down operation, and an inner circumferential surface and a lower end surface of the central groove 64. Consists of right angle edge seal lip 62 is formed by,

When the push bar 40 moves upward by the gas pressure inside the cylinder 30, the arc-shaped inclined surface 42 of the push bar 40 and the edge seal lip 62 of the valve seal 60 come into close contact with each other to move the gas. It serves to stop the gas movement between the 46 and the X chamber chamber (X).

As shown in FIG. 10, the push support 50 has a cylindrical shape formed on top of the cylinder 30 to serve as a stopper.

The upper portion has a central through-hole 51 of the upper portion formed so that the small diameter portion 41 of the push bar 40 penetrating through the upper inner hole 63 of the valve seal 60 penetrates and protrudes outward from the upper side of the cylinder 30. A lower portion is formed at the lower side of the central through hole 51 to form a central groove 52 having a large inner diameter formed to insert and bond the valve seal 60, and an outer groove 53 formed at one side of the side to insert the gas sealing O-ring 54. It can be seen that it is composed of).

As shown in FIG. 11, the gas flow passage tube 70 is a cylindrical tube formed in a straight line having an outer diameter of 2.5 mm to 10 mm, and has a gas moving passage 71 formed at an inner diameter of 1.0 mm to 8.0 mm in the center. An upper end 72 inserted into the lower center groove 45 of the push bar 40 to be adhesively fixed to the inner surface 44 of the central groove, and the gas sealing O-ring 87 of the upper central portion of the piston 81. The lower portion 73 is inserted into the central inner groove 92 leading to the lower inner center of the piston rod 91 and the lower portion of the piston rod 91, and the gas movement passage 71 to compensate for the weakness that can be easily bent when formed of synthetic resin. It consists of a straight metal bar 74 inserted and internally inserted.

It is built in the cylinder 30, the inner center groove 92 (space) is formed in the middle part so that the gas flow passage tube 70 reciprocates up and down, the upper part is open, the lower part is 12 is shown in FIG. 12, which has a blockage and a lower portion penetrates through the central hole of the lower spindle support 130 of the outer cylinder 120 and is fixed by the clip 160.

The upper portion has the same diameter as the inner diameter of the cylinder 30, and when the cylinder 30 rises, the piston portion 81 for supporting the lower portion of the cylinder 30 so as not to rise any more, and the piston portion 81 It is formed to extend to the bottom of the cylindrical shape and smaller than the diameter of the piston 81, the lower portion passes through the lower hole of the cylinder 30 and the central hole 132 of the spindle support 130 of the outer cylinder 120 It is formed so as to, the lower portion 96 is provided with a lower portion 96 is provided with a piston unit 90 is a part formed integrally formed by the die-casting injection or synthetic resin injection by a mold to be described in more detail,

The outer groove 83 is formed on the side of the piston portion 81 and formed so that the gas sealing O-ring 87 made of an elastic body that serves as a gas sealing function between the X chamber chamber (X) and the Y chamber chamber (Y) is inserted. And an inner step groove 82 formed on one side of the upper central through-rim of the piston part 81 and on which the support member 85 is seated to prevent another O-ring 84 from being detached. Is formed in the lower portion of the jaw groove 82, the gas groove passage pipe 70 is penetrated and the inner groove 86 is inserted into another O-ring 84 to function as a gas sealing, and the gas passage pipe 70 It is formed so as to penetrate through the inside of another O-ring 84 in the upper middle of the piston portion 81 to the lower portion of the inner central portion of the piston rod 91, and has a center having a length of at least the up and down stroke distance of the piston rod 91. Boundary between the inner groove 92 and the piston portion 81 and the piston rod portion 91 of the piston body 90 And an outer diameter surface of the piston rod 91 in the central inner groove 92 above the piston rod 91 so as to allow gas to move from the X chamber chamber X to the Y chamber chamber Y. A gas movement hole 98 penetrating up to 95),

 The lower portion 96 of the piston body 90 formed to be inserted into the central hole 132 of the spindle support 130 and the spindle support 130 in contact with the upper surface smoothly rotates when the piston body 90 rotates. It consists of a boundary surface 94 consisting of a right angle step of the upper portion and the lower portion 96 and a groove 97 formed to be inserted into the lower portion 96, the clip 160 is inserted so as to function It can be seen that.

The rod seal 100 and the rod guide 110 formed at the lower portion of the cylinder 30 are internally installed inside the cylinder 30 through the lower portion 96 of the piston rod body 90, and the dustproof rubber outside the cylinder lower portion. 150 is inserted and formed to absorb the impact of the cylinder 30.

Conventional length adjusting gas spring is the piston 80a and the piston rod (30a) is a separate type, the outer diameter surface of the piston rod made of a metal rod is a pin hole, a scratch, etc. on the outer diameter surface of the metal rod forming a piston rod Minimize pin hole, scratch, etc. through grinding process, and surface treatment with chromium plating to prevent oxidation of the ground surface. Grinding of outer diameter surface with pin hole, scratch, and grinding Due to the rough surface, roughness of the surface of the chromium plated film is caused by unevenness of plating density and fine plating at the micro parts, and the roughness of the surface is roughened, and the outer diameter surface treated with chromium plating is 2 to 3 to improve the rough surface roughness. The piston rod moves up and down through the center of the rod seal by improving the surface roughness through a series of puffing operations. While operating, the damage of the seal lip of the rod seal was minimized to maintain gas tightness and durability.

In the present invention, when the piston unit 81 and the piston body 90 of the piston rod 91 formed integrally is formed of a metal by die casting injection by a mold,

It is a cylindrical cemented carbide mold made of special cemented carbide, which has a cylindrical inner through-hole having an exact roundness, and the inner diameter of the inner through is smaller than the outer diameter of the injection-molded piston rod 91 and is intended to be achieved at the same time. It is formed to have the same dimensions as the outer diameter of the piston rod 91, the cylindrical mold length is 20% to 40% of the total length of the piston rod 91, the appropriate length is 30% of the total length, super hard mold The inner surface roughness of the inner through hole is so high that it is configured to maintain high gloss like the mirror surface when viewed in natural light, and the outer diameter surface 95 of the piston rod 91 is made of the ultra hard mold by the ultra hard mold. The outer diameter surface 95 of the piston rod 91 is formed with the correct roundness based on the cylindrical roundness of the inner hole of the cemented carbide mold by compressing and inserting it into the through hole. Definition The exact straightness of the piston rod 91 is formed based on the length of the cemented carbide die, and the surface roughness of the outer diameter surface 95 of the piston rod 91 is greatly increased based on the high inner roughness of the inner through hole of the cemented carbide die. When the outer diameter surface 95 is compressed and inserted into the cemented carbide die, the structure of the piston rod portion 91 and the outer diameter surface 95 is uniformly dense, so that the piston rod 91 has an accurate roundness, straightness and improved performance. To make the outer diameter surface 95 having surface roughness,

A synthetic resin-based adhesive is applied to the entire outer diameter surface 95 of the piston rod 91 to form an adhesive layer 95-1 of a thin film, and the entire outer portion of the adhesive layer 95-1 is made of engineering plastic. By applying appropriate heat to the heat-shrinkable tube formed of a thin film having excellent wear resistance and corrosion resistance, the entire outer diameter surface 95 of the piston rod 91 and the adhesive layer 95-1 are pressed and coated to completely prevent oxidation and injection. The piston rod 91 is sealed by the heat shrinkable tube 95-2 by completely covering the fine pin holes and scratches generated and formed on the outer diameter surface 95 of the piston rod 91 in the molding process. (100) It is configured to enhance the gas sealing force and durability between the rod seal 100 and the outer diameter surface 95 of the piston rod 91 during the vertical operation through the center. Heat-shrinkable tube is a rigid thin tube made of engineering plastic with high strength, wear resistance, oil resistance, oxidation resistance, etc., and shrinks about 10% to 50% when the tube is subjected to a proper temperature. 2) The thickness of 0.01mm ~ 0.5mm is appropriate. The shrinkage method allows a heat-shrinkable tube to have a constant thickness on the outer diameter surface 95 of the entire piston rod portion 91 by passing heat, steam, or an oven within an appropriate temperature range in which the heat-shrinkable tube is contracted to a length-adjustable gas spring. By contracting to close contact with the outer surface of the piston rod 91 to achieve a complete oxidation prevention and gas sealing on the outer surface (95). However, since the piston part 81 is built in the inside of the cylinder 30 filled with nitrogen gas which is inert gas, it does not become oxidative corrosion.

In the present invention, when the piston unit 81 and the piston body 90 of the piston rod 90 formed integrally is formed of a synthetic resin material by injection of the synthetic resin by a mold,

It is a cylindrical cemented carbide mold made of special cemented carbide, which has a cylindrical inner through-hole having an exact roundness, and the inner diameter of the inner through is smaller than the outer diameter of the injection-molded piston rod 91 and is intended to be achieved at the same time. It is formed in the same dimension as the outer diameter of the piston rod 91, the cylindrical mold length is 20% to 40% of the total length of the piston rod 91, the appropriate length is 30%, the inner cavity of the super hard mold The surface roughness of the surface is very high, so that it is formed to have high gloss like the mirror surface when viewed in natural light, and the above-described superhard mold preheated to an appropriate temperature capable of thermal deformation of the synthetic resin material constituting the piston rod 91. By inserting the outer diameter surface 95 of the piston rod 91 into the inner bore of the superhard mold by pressing it in and out based on the cylindrical roundness of the inner bore of the super hard mold. The outer diameter surface 95 of the stone rod portion 91 has an accurate roundness, and the correct straightness of the piston rod 91 is formed on the basis of a suitable cemented die length, and a high inner roughness of the inner hole of the cemented die. On the basis of this, the surface roughness of the outer diameter surface 95 of the piston rod 91 is greatly improved, and when the outer diameter surface 95 is compressed and inserted into the ultra hard mold, the structure of the outer diameter surface 95 of the piston rod 91 is reduced. Uniformly compacted, and thus the piston rod 91 makes the outer diameter surface 95 with accurate roundness, straightness and improved surface roughness,

A synthetic resin-based adhesive is applied to the entire outer diameter surface 95 of the piston rod 91 to form an adhesive layer 95-1 of a thin film, and the entire outer surface of the adhesive layer 95-1 is made of engineering plastic, A heat-shrinkable tube formed of a thin film having excellent wear resistance and corrosion resistance, and by applying appropriate heat, compressing and coating the entire outer diameter surface 95 of the piston rod 91 and the whole adhesive layer 95-1 to the piston unit 90 In the injection molding process, the piston rod 91 is completely sealed by covering the pin hole and the scratch formed on the outer diameter surface 95 of the piston rod 91 with the heat shrinkable tube 95-2. (100) It is configured to enhance the gas sealing force and durability between the rod seal 100 and the outer diameter surface 95 of the piston rod 91 during the vertical operation through the center. Heat-shrinkable tube is a rigid thin tube made of engineering plastic with high strength, wear resistance, oil resistance, oxidation resistance, etc., and it shrinks by about 10% to 50% when a proper temperature is applied to the tube. 2) The thickness of 0.01mm ~ 0.5mm is appropriate. The contraction method is a heat shrinkability by passing the heat, steam or oven within the temperature range of the proper temperature that the heat shrinkable tube is contracted to the length control gas spring and the proper temperature range that the synthetic resin constituting the piston rod 91 is not thermally deformed. Enhances gas sealing force and durability between the rod seal 100 and the outer diameter surface 95 of the piston rod portion 91 by allowing the tube to shrink and adhere to the entire outer diameter surface 95 of the piston rod portion 91. It is configured to

The outer cylinder 120 is, as shown in Figure 14, the slide member 140 made of synthetic resin is formed by pressing the inner surface of the open upper portion of the outer cylinder 120,

In order to prevent the slide member 140 from being separated, one or more inner protrusions 121 formed on the upper inner edge, the lower end portion are formed on the curved portion 123 bent in the inward direction, and the upper portion of the curved portion 123 And at least two left and right symmetrical inner cylinders 122 inwardly directed to the inside, a spindle support 130 formed between the bent portion 123 and the inner protrusions 122, and the spindle support 130. ) Can be seen that the outer portion 131 is formed with a central hole 132 therein.

In the surface treatment of the outer diameter surface of the outer cylinder 120, the outer diameter surface was conventionally coated to prevent oxidation corrosion,

In the present invention, in the surface treatment of the outer cylinder 120, a synthetic resin-based adhesive is applied to the entire outer diameter surface 124 of the outer cylinder 120 to form a thin film adhesive layer (124-1), the adhesive layer (124-) 1) The entire outer diameter of the outer cylinder 120 and the entire outer diameter surface of the outer cylinder 120 by applying appropriate heat as a heat-shrinkable tube formed of a thin film that is excellent in high strength, wear resistance, corrosion resistance and can realize various colors made of the engineering plastic By pressing and coating the adhesive layer 124-1, various colors can be realized based on perfect oxidation prevention and customer's request. Heat-shrinkable tube is a rigid thin tube made of engineering plastic with high strength, abrasion resistance, oil resistance, oxidation resistance, etc., and it shrinks by about 10% to 50% when a proper temperature is applied to the tube. 2) The thickness of 0.01mm ~ 0.5mm is appropriate. In the contraction method, the heat-shrinkable tube is contracted to a constant thickness on the outer diameter surface 124 of the entire outer cylinder 120 by passing heat, steam, or an oven within a proper temperature range in which the heat-shrinkable tube is contracted by the length adjusting gas spring. In order to be in close contact with each other, the outer cylinder 120 of the outer diameter surface 124 may be completely prevented from oxidation and implement an outer cylinder 120 having various colors.

15 shows another surface treatment of another outer cylinder 120. The outer cylinder 120 is applied to the inner diameter surface 125 and the outer diameter surface 124 of the outer cylinder 120 by applying nitriding heat treatment. ~ 10 microns to form a solid outer side white layer (124a) and the inner side white layer (125a) consisting of iron and nitrogen compounds, from the white layer to the outer surface nitride diffusion layer 124b containing nitrogen from 100 to 200 microns and The inner nitride diffusion layer 125b is formed to prevent oxidative corrosion and to significantly improve the strength of the iron material of the outer cylinder 120. The metal thickness T of the outer cylinder 120 is equal to the thickness of the nitride layer from the inner and outer diameter surfaces of 1.25 to 2.5. By applying a nitriding heat treatment to the outer cylinder 120 made of a metal thickness (T) of 0.8 mm ~ 1.6 mm to prevent the oxidation of the inner and outer surfaces of the outer cylinder 120, at the same time the external force bearing strength of the outer cylinder 120 Greatly improves.

The operation of the up and down operation, when the push bar 40 is pressed in a state in which gas is inside the cylinder 30 at a predetermined pressure, the arc-shaped inclined surface 42 of the push bar 40 moves in the a direction so that the valve seal ( Since an open space is formed between the lower edge seal lip 62 of the 60 and the inclined surface 42 of the arc shape, the gas in the Y chamber chamber Y is transferred through the gas movement hole 98 above the piston rod 91. After flowing into the central inner groove 92 of the piston rod 91, the upper portion is moved along the gas movement passage 71 of the gas movement passage tube 70 to move the gas movement hole 46 of the push bar 40. It flows into the X chamber room (X) through. Therefore, since the lower end of the piston body 90 is fixed to the spindle support 130 by the clip 160, the cylinder 30 is raised in the b direction by reaction (see Fig. 5). The top plate of the chair coupled to the inclined portion 31 also rises and the chair is raised. In the case of reducing the length of the gas spring, the procedure is reversed.

In addition, when the external force pushing the push bar 40 is removed, the push bar 40 moves by itself in the b direction due to the gas pressure in the chamber X inside the cylinder 30, and thus the circular arc of the push bar 40. Since the inclined surface 42 of the shape is in close contact with the lower seal seal 62 of the valve seal 60, the gas movement path is blocked, so the gas movement between the X chamber chamber X and the Y chamber chamber Y is stopped and the piston is integrally formed. 90 stops the operation, and thus the cylinder 30 stops rising in the b direction.

The above operation is repeated to operate.

The present invention is a single-cylinder structure, the gas flow passage tube is built into the cylinder and the piston integral body, the piston integral structure consisting of the piston portion and the piston rod portion integral, the cylinder outer diameter of the straight outer diameter surface of the cylinder into the cylindrical cemented carbide inside By passing through the surface, it is possible to improve the accuracy of roundness, straightness and surface roughness of the outer diameter surface of the cylinder.The spindle support of the outer cylinder has a bent portion that rounds inwardly with the lower end of the outer cylinder, and at least two inwardly upwards The protrusion support is fixed so that the spindle support is fixed without welding between the bent portion of the outer cylinder bottom portion and the protrusion protrusion, and the heat-shrinkable tube is crimped on the outer diameter surface of the cylinder, the piston rod portion and the outer cylinder, thereby allowing only the outer diameter of a conventional solid By applying various colors to the surface of customers We can produce products that suit the taste and taste, and provide electricity for product innovation and manufacturing cost reduction by using heat shrinkable tube, which is an environmentally friendly method, for waste water pollution and environmental pollution problems caused by conventional polishing, plating and painting work processes. It is an invention that realizes a great innovation of the length regulating gas spring, which has improved international competitiveness.

 Figure 1 is a longitudinal sectional view showing a conventional regulating gas spring

 Figure 2 is a cross-sectional view showing a valve assembly in a conventional length regulating gas spring

 Figure 3 is a cross-sectional view showing a piston assembly in a conventional length regulating gas spring

 Figure 4 is a longitudinal cross-sectional view showing a length adjustment gas spring of the present invention

 Figure 5 is a state in which the cylinder of the adjustable gas spring of the present invention is raised

 Figure 6 is a detailed view of the cylinder of the present invention

 Figure 7 is a detailed view of the upper cylinder cylinder of the present invention

 Figure 8 is a detailed view of the push bar of the present invention

 9 is a detailed view of the valve seal of the present invention

 10 is a detailed view of the push support of the present invention

 11 is a detailed view of the gas flow passage pipe of the present invention;

 12 is a detailed view of the integral piston of the present invention

 Figure 13 is a detailed view of the piston portion of the piston unit incorporated in the cylinder of the present invention

 Figure 14 is a detailed view of the outer cylinder of the present invention

 Figure 15 is another state diagram of the outer cylinder in the present invention

<Description of the symbols for the main parts of the drawings>

Cylinder 30, inclined portion 31, outer diameter surface 32, adhesive layer 32-1, heat shrinkable tube 32-2, cylinder inner surface 33, boundary surface 34, end inner surface 35, Inclined surface 36, push bar 40, small diameter surface 41, inclined surface 42, large diameter surface 43, the central groove inner surface 44, the central groove 45, the gas movement hole 46, Push support 50, center hole 51, center groove 52, outer groove 53, O-ring 54, valve seal 60, inner peripheral seal lip 61, corner seal lip 62, upper inner hole (63), central groove (64), gas flow passage pipe (70), gas flow passage (71), upper end portion (72), lower portion (73), metal bar (74), piston portion (81), Inner step groove 82, Outer groove 83, O-ring 84, Support member 85, Inner groove 86, O-ring 87, Piston body 90, Piston rod 91, Center inner Groove 92, inner surface 93, interface 94, outer surface 95, adhesive layer 95-1, heat shrinkable tube 95-2, lower portion 96, groove 97, gas Moving hole (98), rod seal (100), metal core (101), rod guide (110), outer cylinder (120), inner protrusion (121), inner protrusion (12) 2), bend 123, outer diameter surface 124, adhesive layer 124-1, heat shrinkable tube 124-2, outer side white layer 124a, outer side nitride diffusion layer 124b, inner diameter surface 125 ), Inner side white layer 125a, inner side nitride diffusion layer 125b, spindle support 130, outer side 131, central hole 132, slide member 140, anti-vibration rubber 150, clip 160 ), Outer cylinder metal thickness (T), X chamber chamber (X), Y chamber chamber (Y)

Claims (16)

In the length-regulated gas spring, a cylindrical outer cylinder 120 having an upper and a lower part opened, and the upper and lower portions of the outer cylinder 120 are built in and moved up and down about the outer cylinder 120 to act as a piston. The upper part of the structure is open, the lower part of the cylindrical cylinder 30 has a through-hole formed in the center, and the press-fit fixed inside the open upper edge of the outer cylinder 120, the built-in cylinder 30 is smoothly up and down Slide member 140, which serves to support to move to, the spindle support 130 is inserted and coupled to the open lower portion of the outer cylinder 120, the central hole 132 is formed in the center and the cylinder 30 ) Is built in the interior and serves to fix the cylinder 30 when moved up and down, and a central inner groove 92 is formed so that the gas flow passage pipe 70 can be moved and the gas is moved to the upper one side. A piston support 90 having a gas movement hole 68 formed therein, and a push support 50 formed at an inner side of an open upper portion of the cylinder 30 to serve as a stopper, and a groove is formed at a lateral middle edge thereof, and a hole is formed at the center thereof. And a valve seal 60 made of an annular rubber and an elastic body, which is internally bonded to the push support 50 to prevent the gas inside the cylinder 30 from flowing out to the outside, and has a through-hole formed in the center thereof. The upper part is inserted into the central through hole of the push support 50 and the valve seal 60 and protrudes to the outside of the upper part of the cylinder 30, and the lower part has an arc shape and has a predetermined step, and an insertion groove is formed in the lower center. A push bar 40 made of synthetic resin having a gas movement hole 46 penetrated to an outer circumferential surface on one side of the insertion groove, and a fixed long insertion and insertion inserted into an insertion groove formed in the middle of the middle portion at the lower portion of the push bar 40. Shape The gas flow passage tube 70 and the synthetic resin or metal material is inserted into the central inner groove 92 leading to the center of the piston body 90, the space is formed to insert the metal bar 74 therein, and the cylinder It is formed in the open lower inner side of the 30, the rubber seal and the rod seal 100 of the material; The rod guide 110 configured below the rod seal 100, the dustproof rubber 150 provided on an upper portion of the spindle support 130 to mitigate the impact of the cylinder 30 moving upward and downward, and the cylinder The clip for fixing to the groove 97 of the lower part 96 of the piston body 90 which passed through the lower central hole of the 30, and penetrated the center hole 132 of the lower spindle support 130 of the outer cylinder 120. Lengthwise gas spring, characterized in that consisting of (160). According to claim 1, wherein the cylinder 30 is the inclined portion 31 of the upper portion coupled to the upper plate of the chair, the outer diameter surface 32 of the cylinder 30 to form the outer surface of the cylinder 30, The inner diameter of the lower one side surface of the cylinder 30 is an end surface inner surface 35 formed larger than the inner diameter of the cylinder inner surface 33, and the boundary surface formed in a stepped shape between the lower end inner surface 35 and the cylinder inner surface 33 34, an inclined surface 36 formed to bend at right angles so as to prevent components formed on the inner surface of the cylinder 30 from being separated outward, and a through hole formed in the center of the lower portion of the cylinder 30. Adjustable gas spring, characterized in that there is. 3. The outer diameter surface 32 of the cylinder 30 comprises: a thin film adhesive layer 32-1 formed by applying an adhesive made of a synthetic resin adhesive to the entire outer diameter surface 32; The adhesive layer 32-1 and the outer surface of the outer diameter surface 32 of the cylinder 30 are press-coated and coated with a high strength, abrasion resistance, corrosion resistance, and a thickness of 0.01 mm to 0.5 mm formed of an engineering plastic capable of implementing various colors. Length-regulating gas spring, characterized in that consisting of a thin film heat shrinkable tube (32-2). delete According to claim 1, wherein the push bar 40 is a rod-shaped rod injection molded of synthetic resin material, the small diameter portion 41 to form an upper portion, and the lower diameter portion formed on the lower side of the circular arc shape toward the bottom A large diameter portion 43 having a predetermined step, an arc-shaped inclined surface 42 forming a boundary between the large diameter portion 43 and the small diameter portion 41, and the gas flow passage tube 70. The upper end of the upper end portion is inserted and bonded to the central groove (45) formed with a central groove inner surface 44 (space) from the lower portion of the large diameter portion (43) to one side of the upper central portion, and the center that is inside of the central groove (45) It is formed to penetrate the groove inner surface 44 and the arc-shaped inclined surface 42, the gas of the Y chamber chamber (Y) to the X chamber chamber (X) through the gas movement passage pipe 70 and the central groove (45) Characterized in that it is composed of a gas moving hole 46 to guide the flow Adjustable gas springs. According to claim 1, The valve seal 60 is a seal made of an annular rubber and an elastic body that is internally bonded to the push support 50, The upper inner through-hole 63 formed in the upper portion, the lower portion of the central groove 64 of the circular space form of the inner diameter larger than the upper inner through-hole 63, and the inside of the small diameter portion 41 of the push bar 40 An inner circumferential surface seal lip 61 having at least one seal lip having a sealing function for preventing the gas inside the cylinder 30 from flowing out to the outside during up and down operation, and an inner circumferential surface and a lower end surface of the central groove 64. Lengthwise gas spring formed by being characterized by consisting of a right angle edge seal lip (62) formed by. According to claim 1, The push support 50 is formed in the upper portion of the cylinder 30 to act as a stopper, the upper portion of the push bar (40) penetrating through the inner through-hole 63 above the valve seal 60 The central through-hole 51 of the upper portion formed so as to penetrate through the small diameter portion 41 of the upper side and protrudes outward the upper side of the cylinder 30, and the lower portion is formed below the central through-hole 51, the valve seal 60 is inserted and bonded Longitudinal adjustment gas spring characterized in that it consists of a central groove 52 of a large inner diameter and an outer groove 53 formed to be inserted into the gas sealing O-ring 54 on one side of the side. According to claim 1, wherein the gas flow passage pipe 70 is a cylindrical pipe formed in a straight line having an outer diameter of 2.5mm ~ 10mm gas center passage 71 formed in the inner diameter of 1.0mm ~ 8.0mm in the center, and the push bar 40 is inserted into the lower center groove 45 and penetrates the upper end 72 which is adhesively fixed to the inner surface 44 of the central groove, and the gas sealing O-ring 87 of the upper middle of the piston 81; And a lower portion 73 inserted into the central inner groove 92 leading to the lower inner center of the piston rod 91 and a straight metal bar 74 inserted into the gas flow passage 71. Length adjustable gas spring characterized in that. According to claim 1, The piston body 90 is embedded in the cylinder 30, the central inner groove 92 (space) in the middle portion so that the gas flow passage pipe 70 reciprocates up and down therein Is formed, the upper part is open, the lower part is blocked and the lower part is a shape fixed through the central hole of the lower spindle support 130 of the outer cylinder 120 and fixed by the clip 160, The upper portion has the same diameter as the inner diameter of the cylinder 30, and when the cylinder 30 rises, the piston portion 81 for supporting the lower portion of the cylinder 30 so as not to rise any more, and the piston portion 81 It is formed to extend to the bottom of the cylindrical shape and smaller than the diameter of the piston 81, the lower portion passes through the lower hole of the cylinder 30 and the central hole 132 of the spindle support 130 of the outer cylinder 120 It is formed to, and consists of a piston rod 91 formed with a lower portion 96 is provided with a groove 97 on the lower side, The outer groove 83 is formed on the side of the piston portion 81 and formed so that the gas sealing O-ring 87 made of an elastic body that serves as a gas sealing function between the X chamber chamber (X) and the Y chamber chamber (Y) is inserted. And an inner step groove 82 formed on one side of the upper central through-rim of the piston part 81 and on which the support member 85 is seated to prevent another O-ring 84 from being detached. Is formed in the lower portion of the jaw groove 82, the gas groove passage pipe 70 is penetrated and the inner groove 86 is inserted into another O-ring 84 to function as a gas sealing, and the gas passage pipe 70 It is formed so as to penetrate through the inside of another O-ring 84 in the upper middle of the piston portion 81 to the lower portion of the inner central portion of the piston rod 91, and has a center having a length of at least the up and down stroke distance of the piston rod 91. Boundary between the inner groove 92 and the piston portion 81 and the piston rod portion 91 of the piston body 90 And an outer diameter surface of the piston rod 91 in the central inner groove 92 above the piston rod 91 so as to allow gas to move from the X chamber chamber X to the Y chamber chamber Y. A gas movement hole 98 penetrating up to 95, a lower portion 96 of the piston body 90 formed to be inserted into the central hole 132 of the spindle support 130, and an upper surface of the spindle support 130; And a boundary surface 94 formed at right angles between the upper and lower portions 96, which contact each other so as to smoothly rotate when the piston body 90 rotates, and is formed below the lower portion 96, and the clip Length adjusting gas spring, characterized in that consisting of a groove (97) formed to be inserted (160). 10. The method of claim 9, wherein the piston body 90 is a die cast injection or synthetic resin injection molding by a mold using a metal or synthetic resin material is characterized in that the piston 81 and the piston rod 91 is formed integrally. Adjustable gas springs. The outer diameter surface (95) of the piston rod (91) comprises: a thin film adhesive layer (95-1) formed by applying an adhesive made of a synthetic resin adhesive to the entire outer diameter surface (95); A thin film heat shrinkable tube having a thickness of 0.01 mm to 0.5 mm formed of an engineering plastic having excellent strength, wear resistance, and corrosion resistance by compressively coating the entire outer diameter 95 of the adhesive layer 95-1 and the piston rod 91. Length adjusting gas spring, characterized in that consisting of (95-2). delete The method of claim 1, wherein the outer cylinder 120 is formed by the slide member 140 made of synthetic resin is pressed into the inner surface of the open upper portion of the outer cylinder 120, In order to prevent the slide member 140 from being separated, one or more inner protrusions 121 formed on the upper inner edge, the lower end portion are formed on the curved portion 123 bent in the inward direction, and the upper portion of the curved portion 123 And at least two left and right symmetrical inner cylinders 122 inwardly directed to the inside, a spindle support 130 formed between the bent portion 123 and the inner protrusions 122, and the spindle support 130. ) Is a length adjustment gas spring, characterized in that consisting of an outer portion 131 formed with a central hole 132 therein. 15. The method of claim 13, wherein the outer cylinder 120 is a thin film adhesive layer (124-1) formed by applying an adhesive made of a synthetic resin adhesive on the entire outer surface (124); Thin heat-shrinkable tube 124 having a thickness of 0.01 mm to 0.5 mm formed of an engineering plastic having high strength, abrasion resistance, and corrosion resistance by compressively coating the entire outer surface of the adhesive layer 124-1 and the outer diameter surface 124 of the outer cylinder 120. -2) length adjustable gas spring, characterized in that consisting of. 14. The outer cylinder 120 is formed of iron and nitrogen compounds from the inner and outer diameter surfaces to 4 to 10 microns by applying nitriding heat treatment to the inner diameter surface 125 and the outer diameter surface 124 of the outer cylinder 120. A rigid outer side white layer 124a and an inner side white layer 125a are formed, and an outer side nitride layer 124b containing nitrogen from 100 to 200 microns and an inner side nitride layer 125b are formed from the white layer. This prevents oxidation corrosion and greatly improves the strength of the iron material of the outer cylinder 120, and the metal thickness (T) of the outer cylinder 120 is 1.25 to 2.5 times the sum of the thickness of the nitride layer from the inner and outer diameter surfaces, and 0.8 mm to 1.6 mm. Length adjusting gas spring, characterized in that consisting of a metal thickness (T). In the operation method of the length adjusting gas spring, when the push bar 40 is pressed while the gas is inside the cylinder 30 at a predetermined pressure, the arc-shaped inclined surface 42 of the push bar 40 descends to seal the valve. Since the open space is formed between the lower edge seal lip 62 of the 60 and the inclined surface 42 of the arc shape, the gas in the Y chamber chamber Y is the gas movement hole 98 above the piston rod 91. The center chamber groove 92 of the piston rod 91, the gas movement passage 71 of the gas movement passage tube 70 and the gas movement hole 46 of the push bar 40 to the X chamber chamber (X). Since the piston unit 90 moves downward, and the lower end of the piston unit 90 is fixed to the spindle support 130 by the clip 160, the cylinder 30 rises by reaction and the push bar. When the external force for pressing the 40 is removed, the push bar 40 rises by itself due to the gas pressure of the chamber X inside the cylinder 30. The arc-shaped inclined surface 42 of the push bar 40 is in close contact with the lower edge seal lip 62 of the valve seal 60 so that the gas flow path is blocked, so that the space between the X chamber chamber X and the Y chamber chamber Y is maintained. The gas movement is stopped and the piston body (90) stops operation, and thus the cylinder (30) operates in such a way as to stop rising.