KR101239916B1 - Method for filling and sealing fluid in a shock absorber - Google Patents

Abstract

The present invention relates to a fluid encapsulation method for sealing by filling gas and oil in a tube in a shock absorber.
According to the present invention, a method of encapsulating fluid in a shock absorber, comprising: a seal unit gripped by a support means installed on a piston rod of the shock absorber and a position fixing means provided outside of the shock absorber; Provided is a fluid filling method of a shock absorber characterized in that an oil is filled into the tube after the seal is fixed to the upper opening of the tube to fix the position of the seal unit.

Description

METHOOD FOR FILLING AND SEALING FLUID IN A SHOCK ABSORBER}

The present invention relates to a fluid encapsulation method of a shock absorber and a shock absorber manufactured by the present invention, and more particularly, to a fluid encapsulation method for filling and sealing gas and oil in a tube in a mono-tubular shock absorber and a shock absorber manufactured by the same It is about.

In general, a vehicle shock absorber is installed between the vehicle body and the axle to prevent vibration and shock received by the axle from the road surface while driving the vehicle to improve the ride comfort, gas and oil in the interior to increase the damping force This seal is filled.

These shock absorbers are classified into a twin tube type in which the oil storage tube is composed of a double wall and a mono tube type consisting of a single wall, according to the structure thereof.

In particular, since the mono-tubular shock absorber uses only one tube, its structure is very simple and easy to assemble.

Such a mono tubular shock absorber is shown by way of example in FIG. 1. The monotube type shock absorber 10 includes a single tube 11, a piston rod 12 having one end inserted into the tube 11 and the other end extending outward through an upper end of the tube 11. It is installed at the lower end side of the piston rod 12 and partitions the inside of the tube 11 into the upper tension chamber 11a and the lower compression chamber 11b, and the body has a tension chamber 11a and a compression chamber 11b. A piston valve 13 having an oil passage 13a for oil flow therebetween, and a free piston positioned inside the tube 11 to partition the upper compression chamber 11b and the lower gas chamber 11c. (14) and a seal assembly (15) provided at an upper end of the tube (11) to seal the upper end of the tube (11) while slidably supporting the piston rod (12).

The seal assembly 15 is a rod guide and an oil seal combined. An upper mounting portion such as an eye 16 or a bolt is coupled to an upper end of the piston rod 12, and an upper portion for installing a dust cover (not shown) or the like immediately below the upper mounting portion, for example, the upper eye 16. The cap 17 is engaged.

In the tube 11, gas is filled in the gas chamber 11c under the free piston 14, and oil is filled in the tension chamber 11a and the compression chamber 11b on the free piston 14.

In filling gas into the gas chamber 11c, a gas injection hole is formed in the lower end of the tube 11 in advance, and the lower end of the tube 11 is inserted with the free piston 14 inserted into the tube 11. Inject gas into the gas chamber 11c through the gas injection hole of the gas chamber 11c so as to block the upper end of the tube 11 so that the free piston 14 with the gas filled thereon does not fall over the upper end of the tube 11. The gas injection hole was welded to seal the gas chamber 11c.

However, such a conventional gas encapsulation method has to go through the process of welding the gas injection hole, there is a problem that not only sludge is generated during the welding operation but also water cooling the welding site after the welding operation.

When the oil is filled in the tension chamber 11a and the compression chamber 11b on the free piston 14, conventionally, the lower end of the piston rod 12 has a free piston (with a gas filled therein). 14) was pushed down to the desired position to fill the oil while securing a space inside the tube 11.

The basic length of the mono tubular shock absorber is determined by the position where the free piston is pushed down for oil filling. For example, when the piston rod 12 lowers the free piston 14 deeply as shown in FIG. 2A to fill the oil, a portion where the piston rod 12 overlaps the tube 11 is formed. Since the base length of the shock absorber becomes relatively small, and the piston rod 12 lowers the free piston 14 shallowly as shown in FIG. 2 (b) to fill the oil, the piston rod 12 Since the portion overlapping with the tube 11 is relatively small, the basic length of the shock absorber becomes large.

By the way, the seal assembly 15 fitted on the piston rod 12 is located outside the upper part of the tube 11 when oil is filled in the inner space of the tube 11, and oil is contained in the inner space of the tube 11. After filling it is inserted into the tube 11. Here, the seal assembly 15 is inserted into the tube 11 by a seal assembly insertion unit (not shown), which lowers and inserts the seal assembly 15 fitted on the piston rod 12 into the tube 11. In order for the seal assembly insertion unit to be in close proximity to the piston rod 12 at the top of the tube 11.

However, when the piston rod 12 with the upper eye 16 and the upper cap 17 coupled to the upper end descends deeply as shown in FIG. 2A, the upper part coupled to the upper end of the piston rod 12 Since the gap between the cap 17 and the upper end of the tube 11 is narrowed, there is no space for the seal assembly insertion unit to work.

Therefore, conventionally, as shown in (b) of FIG. 2, the piston rod 12 descends shallowly to widen the gap between the upper cap 17 coupled to the upper end of the piston rod 12 and the upper end of the tube 11. Although the seal assembly insertion unit has secured a space to work, in this case, there is a problem that the basic length of the shock absorber is increased as described above.

In contrast, in the state where the upper eye 16 and the upper cap 17 are not coupled to the piston rod 12, the seal assembly insertion unit even if the piston rod 12 is lowered to the position shown in FIG. Since the piston rod 12 may be in close proximity, the piston rod 12 is inserted into the tube 11 without engaging the upper eye 16 and the upper cap 17 so that the piston rod 12 may be inserted. Although there is a way to reduce the basic length of the shock absorber by lowering it deeply to the position shown in FIG. 2 (a) to fill the oil and then inserting it into the seal assembly 15, the tube 11 is remarked. In order to couple the upper eye 16 and the upper cap 17 to the upper end of the duly inserted piston rod 12, the piston rod 12 must be fixed and worked, so the means for fixing the piston rod 12 are separately And complicated assembly work There is a troublesome problem.

In order to cope with this conventional problem, the Applicant inserts a free piston after injecting gas into the tube, and vacuums the space above the free piston inside the tube through a hole formed in the upper side of the tube and injects oil therein. , Has developed a fluid sealing device and method for sealingly fixing an oil seal integrated rod guide to a top of a tube by caulking. The applicant's technology is disclosed in Korean Patent Registration Publication No. 10-0880820.

The fluid encapsulation device and method according to the present applicant has advantages such as a separate coating or tube surface treatment process may be omitted after assembly, but only an oil seal integrated rod guide may be used. It was not possible to use products with separate rod guides. In addition, in the final stage of shock absorber assembly, the fixing of the rod guide could be performed only by the caulking method and not by other methods such as the curling method.

Accordingly, the present invention is to solve the problems of the prior art, by extending the piston rod to fix the rod guide to prevent the fall of the rod guide during vacuum after gas injection, it is possible to use the oil seal integrated rod guide It is also an object of the present invention to provide a fluid sealing method of a shock absorber in which an oil seal and a rod guide can use a product separated from each other, and a shock absorber manufactured thereby.

According to the present invention for achieving the above object, a method for enclosing a fluid in a shock absorber, a seal unit gripped by a support means provided on the piston rod of the shock absorber and a position fixing means provided outside of the shock absorber Is inserted into the tube top opening of the shock absorber to seal the top opening of the tube, thereby fixing the position of the seal unit, and then filling the oil into the tube.

After the step of filling the oil, it is preferable to include a seal unit fixing step of permanently fixing the position of the seal unit.

As the seal unit, a rod guide and an oil seal may be used separately. In the seal unit fixing step, the position of the seal unit may be permanently fixed by curling.

As the seal unit, a rod guide and an oil seal may be integrally formed, and in the seal unit fixing step, the position of the seal unit may be permanently fixed by caulking.

Prior to the filling of the oil, preparing a tube having a fluid injection hole for injecting gas and oil in the upper portion and closing the lower portion thereof, and inserting a free piston in the upper opening of the tube, Sealing the top opening and pushing the free piston into the tube by compressing a piston rod after injecting gas through the fluid injection hole.

It is preferable to further include vacuuming the inner space of the tube to be filled with oil before filling the oil into the tube.

The seal unit is inserted into the top opening of the tube so as not to close the fluid injection hole before filling the oil into the tube, and further added to the top opening of the tube to close the fluid injection hole after the oil is filled. It is preferred to be inserted.

According to another aspect of the present invention, a shock absorber is provided between the vehicle body and the axle to absorb vibrations or shocks received by the axle from the road surface when the vehicle travels, and the fluid in the shock absorber by the fluid sealing method of the shock absorber described above. The fluid injection hole is formed so that the fluid can be sealed, and the fluid injection hole is kept open when the fluid is injected by the fluid filling method, and the seal unit is completed when the fluid filling operation of the fluid filling method is completed. A shock absorber is provided that is closed by.

The shock absorber includes a single tube having the fluid injection hole formed therein, a piston rod having one end inserted into the tube and the other end extending outward through an upper end of the tube, and a lower end of the piston rod. A piston valve installed at the side to partition the inside of the tube into an upper tension chamber and a lower compression chamber; a free piston positioned inside the tube to partition the upper compression chamber and a lower gas chamber; The seal unit may be installed at an upper end of the tube to seal the tube and to close the fluid injection hole.

According to the present invention, by extending the piston rod and fixing the rod guide to prevent the rod guide from falling during vacuum after gas injection, the oil seal integral rod guide can be used as well as the oil seal and the rod guide separated from each other. A fluid encapsulation method of a shock absorber capable of using a product and a shock absorber manufactured thereby can be provided.

In addition, according to the fluid encapsulation method of the present invention, in the final stage of assembly of the shock absorber, fixing of the rod guide and the oil seal and sealing the shock absorber may be performed by other methods such as a curling method in addition to the caulking method. The work of the upper fixing part may be any shape of the eye and the bolt.

1 is a cross-sectional view showing a conventional mono-tubular shock absorber,
Figure 2 is a cross-sectional view for explaining a fluid filling method for a mono-tubular shock absorber according to the prior art, and
3 to 6 are cross-sectional views for explaining a fluid filling apparatus and method for a mono tubular shock absorber according to the present invention.

Hereinafter, a fluid sealing apparatus and a method of a shock absorber according to a preferred embodiment of the present invention with reference to the accompanying drawings will be described. As shown in Figures 3 to 6, the fluid filling device of the shock absorber according to an embodiment of the present invention, the fluid injection nozzle 110 for injecting a fluid, such as gas and oil into the tube 11 of the shock absorber And a position for supporting the seal unit 20 including the rod guide 21 and the oil seal 22 in a fixed position in cooperation with supporting means such as a stopper 12a installed on the piston rod 12 during oil injection. Fixing means 120 and sealing fixing means 130 for sealingly fixing the seal unit 20 after the gas and oil injection is completed.

The mono-tubular shock absorber to which the fluid filling apparatus and method of the present invention is applied may be the same as the shock absorber described in the prior art, and the same reference numerals will be used for the same configuration as the prior art.

In the present invention, the fluid injection hole 11d is formed in the tube 11 of the shock absorber in advance. The position of the fluid injection hole 11d is set close to the upper end of the tube 11, and more particularly, the upper end of the tube 11 is closed by the free piston 14 or the rod guide 21 during gas or oil injection. At the same time, the fluid injection hole 11d is preferably formed at a position that may not be closed.

The fluid injection nozzle 110 may be installed to be movable from side to side on one side of the tube 11 and may be sealingly inserted into the fluid injection hole 11d formed in the tube 11. A hydraulic cylinder 111 for moving the fluid injection nozzle 110 left and right is connected to the fluid injection nozzle 110 to move the fluid injection nozzle 110 when necessary.

In addition, a gas supply device, a vacuum pump, and an oil supply device may be selectively connected to the fluid injection nozzle 110. The gas supply device may include a gas storage tank, a compressor, and the like, and the oil supply device may include an oil storage tank, a compressor, and the like. These gas supply devices, vacuum pumps, and oil supply devices are well-known technical configurations, and thus will not be described in detail herein.

The position fixing means 120 is used to vacuum the space above the free piston 14 of the tube 11 and to inject oil after the gas injection and the free piston 14 insertion are completed. The position fixing means 120 includes a rod guide 21 and an oil seal 22 in cooperation with support means such as a stopper 12a installed on the piston rod 12, as shown in FIGS. 4 and 5. The seal unit 20 is supported at a fixed position.

If the stopper 12a is not provided on the piston rod 12, a washer or the like installed on the top of the piston valve 13 may be utilized as the support means. According to the present invention, since the position fixing means 120 can cooperate with the supporting means such as the stopper 12a to keep the seal unit 20 fixed at a fixed position on the upper end of the tube 11, the tube 11 Even when the inside of the vacuum is vacuumed, the rod guide 21 and the like of the seal unit 20 are not sucked into the inside of the tube 11.

In order to allow the support means to cooperate with the position fixing means 120, the operation is performed while the piston rod 12 is in tension during the vacuum treatment and the oil injection. As the position fixing means 120, the seal unit 20 can be fixed in position in cooperation with the supporting means in the state where the piston rod 12 is tensioned, and if necessary, the seal unit 20 is held together with the supporting means. Any configuration can be used as long as the seal unit 20 can be moved up or down in the state. To this end, the position fixing means 120 may include a driving device such as a cylinder or an actuator.

4 and 5 show that the two position fixing means 120 in contact with the upper left and right of the oil seal 22, but this is only an example and the number and shape of the position fixing means 120 is the present invention. It does not limit.

When the injection of gas and oil into the tube 11 is completed, the seal unit 20 temporarily fixed is moved downward by the above-described position fixing means 120 and the supporting means to inject gas and oil. The fluid injection hole 11d formed in the upper end of the tube 11 is closed. In this state, a seal fixing means 130 is used to seal fix the seal unit 20.

The seal fixing means 130 sealably seals the seal unit 20 so that the seal unit 20 can close the upper end of the tube 11 by a processing method such as curling or caulking. The seal fixing means 130 may be installed to be movable by the hydraulic cylinder.

According to the present invention, the fluid absorber of the shock absorber can be sealed by filling the shock absorber with gas and oil through the following process.

According to the present invention, the lower eye 18 may be pre-mounted at the lower end of the tube 11 before filling the gas and oil into the tube 11 of the shock absorber 10. In addition, a fluid injection hole 11d is previously formed in the upper end side of the tube 11. Although a bolt is formed at the top of the piston rod 12 in the drawing, the upper eye 16 and the upper cap 17 as shown in FIG. May be combined.

As described above, the position of the fluid injection hole 11d is determined to be close to the top of the tube 11, more specifically, the tube 11 by the free piston 14 or the rod guide 21 when gas or oil is injected. It is preferable that the upper end of the top face 9) is formed at the same time that the fluid injection hole 11d cannot be closed.

First, as shown in FIG. 3, the free piston 14 is fitted into the top opening of the tube 11 to seal the top opening of the tube 11. Here, it is necessary to prevent the side of the free piston 14 from blocking the fluid injection hole 11d, so that the upper part of the free piston 14 slightly exits above the top of the tube 11 so that the free piston 14 ), The position of the free piston 14 can be temporarily fixed in the state of being fitted to the upper end of the tube (11). Here, the pre-piston insertion device for inserting the free piston 12 into the tube 11 and temporarily fixing the position before the gas filling is well known, and thus will not be described in detail herein. do.

Next, the fluid injection nozzle 110 is moved to be sealedly inserted into the fluid injection hole 11d to inject an inert gas into the tube 11 through the fluid injection hole 11d.

Subsequently, as shown in FIG. 4, the free piston 14 is pushed downward from the top of the tube 11 by compressing the piston rod 12. At this time, the seal unit 20, that is, the rod guide 21 and the oil seal 22 is held by the support means such as the stopper 12a and the position fixing means 120 above the piston valve 13. .

According to the invention, it is necessary to pull the piston rod 12 upwards in order to hold the seal unit 20 by the support means and the position fixing means 120, which is a separate pull for pulling the piston rod 12. This can be accomplished by utilizing a device such as an actuator or by utilizing the reaction force of the free piston 14.

In addition, according to the present invention, since the piston rod 12 can be artificially stretched so that the seal unit 20 can be temporarily fixed between the support means and the position fixing means 120, the seal unit 20 is a single unit. The fluid encapsulation method according to the invention can be applied both in the case of components or in separate components, that is, in the case of a rod guide 21 and an oil seal 22. This saves costs by using relatively inexpensive rod guides and oil seal detachable seal units rather than using relatively expensive rod guides and oil seal integral seal units.

The depth at which the free piston 14 is pushed is such that the free piston 14 is located below the fluid injection hole 11d while the top opening of the tube 11 can be closed by the rod guide 21. It is preferable to be determined. Closing the top opening of the tube 11 by the rod guide 21 is inserted only to the extent that the rod guide 21 does not close the fluid injection hole 11d.

Here, since the seal unit insertion device for lowering the seal unit 20 fitted on the piston rod 12 and inserting the seal unit 20 into the upper end of the tube 11 is a known technique, it will not be described in detail herein.

Next, the fluid injection nozzle 110 is hermetically inserted into the fluid injection hole 11d to extract air from the space between the seal unit 20 and the free piston 14 through the fluid injection hole 11d to close the space. Make a vacuum In this case, as described above, it will be appreciated that the space is vacuumed by a vacuum pump selectively connected to the fluid injection nozzle 110.

Next, as shown in FIG. 5, oil is injected from the fluid injection nozzle 110 through the fluid injection hole 11d into the space between the seal unit 20 and the free piston 14. In this case, as described above, it will be appreciated that the space is filled with high pressure oil by an oil supply device which may be selectively connected to the fluid injection nozzle 110.

Here, since the seal unit 20 is gripped by the support means such as the stopper 12a and the position fixing means 120, and is fixed, the free piston is supplied with oil at a high pressure into the fluid injection hole 11d. 14 descends below the tube 11. The oil injection continues until the internal pressure of the tube 11 reaches the set pressure and the free piston 14 reaches the desired position.

When the high pressure oil is injected into the space between the seal unit 20 positioned at the upper end of the tube 11 and the free piston 14 in a gas-filled state below, the free piston 14 is Since the pressure of the gas enclosed in the gas chamber 11c below it is overcome and pushed, it is possible to lower the free piston 14 to a desired position without pushing it by the piston rod 12.

Therefore, according to the present invention, since the piston rod 12 does not need to be inserted deeply into the tube 11, the gap between the upper cap 17 coupled to the upper end of the piston rod 12 and the upper end of the tube 11. This can be kept wide so that sufficient space for the seal unit insertion apparatus to work can be secured.

Next, after the free piston 14 has reached the desired position, as shown in FIG. 6, the seal unit 20 such that the rod guide 21 side of the seal unit 20 blocks the fluid injection hole 11d is shown. Push down to lower.

Next, the sealing fixing means 130 is moved to curl the upper end of the tube 11 protruding upward of the oil seal 22 while the side of the rod guide 21 blocks the fluid injection hole 11d. As a result, the position of the seal unit 20 is permanently fixed, and the fluid injection hole 11d can be permanently closed without the need for performing a separate process such as welding. Furthermore, since no post-processing such as welding is performed, no additional surface treatment is required on the outer surface of the tube, thereby reducing costs and improving productivity.

According to the present invention, in addition to curling, the position of the seal unit 20 can be permanently fixed by processing such as caulking.

In addition, the fluid encapsulation device and method according to the present invention may be utilized even when the fluid is filled in other types of shock absorbers such as twin-tube shock absorbers other than the mono-tube shock absorbers.

While the present invention has been particularly shown and described with reference to specific embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the present invention as defined by the appended claims. And should not be construed as limiting the scope of the present invention, but rather should be construed as exemplifying the invention.

10: shock absorber, 11: tube, 11d: fluid injection hole, 12: piston rod, 12a: stopper, 13: piston valve, 14: free piston, 20: seal unit, 21: rod guide, 22: oil seal, 110 : Fluid injection nozzle, 120: position fixing means, 130: sealing fixing means

Claims (8)

As a method of filling a fluid into a shock absorber,
Holding the seal unit up and down by supporting means installed on the piston rod of the shock absorber and a position fixing means provided outside of the shock absorber;
Securing the position of the seal unit by inserting the gripped seal unit into the tube top opening of the shock absorber to seal the top opening of the tube;
Filling oil into the tube;
A sealing unit fixing step of permanently fixing the position of the sealing unit after the filling of the oil;
Including;
A rod guide and an oil seal are used separately as the seal unit, and in the seal unit fixing step, the position of the seal unit is permanently fixed by curling. delete delete delete The method according to claim 1,
Prior to the filling of the oil, preparing a tube having a fluid injection hole for injecting gas and oil in the upper portion and closing the lower portion thereof, and inserting a free piston in the upper opening of the tube, Sealing the top opening and forcing the free piston into the interior of the tube by compressing a piston rod after injecting gas through the fluid injection hole. . The method according to claim 5,
Vacuuming the inner space of the tube to be filled with oil before filling the oil into the tube;
The seal unit is inserted into the top opening of the tube so as not to close the fluid injection hole before filling the oil into the tube, and further added to the top opening of the tube to close the fluid injection hole after the oil is filled. A fluid sealing method of a shock absorber, characterized in that inserted. delete delete

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