CN1158429C - Elastic railway guide rail fastening clip and fixing device cooperating with it - Google Patents

Abstract

A clip for fastening a railway rail to an underlying foundation, of the type having an anchoring leg whereby the clip is retained by anchoring device, has means to resist unauthorised disengagement of the clip from the anchoring device comprising first locating means on the anchoring leg at a region spaced from the free end thereof, cooperating with second locating means inside the housing of the anchoring device when the anchoring leg of the clip is inserted therein. The clip for fastening a railway rail to an underlying foundation has stop means engaging cooperating means on the anchoring device to prevent overdriving of the clip into the anchoring device.

Description

Elastic railway guide rail fastening clip and fixing device cooperating with it

technical field

The invention relates to an elastic rail fastening clip and a fixing device cooperating with it.

Background technique

A common system for fastening railway rails to an underlying base such as concrete or wooden rail ties consists of a pair of fixtures which, when installed in place, are secured to the bases on either side of the rail, These devices hold the fixed legs of the resilient rail fastening clips supported on the rail. This structural solution is disclosed in British Patent GB 1510224, which particularly relates to a railway rail fastening clip called an "e" clip, one of which is a rod bent from an elastic material so that it can be It is depicted sequentially from one free end to the other as having a straight fixed leg, a reversely curved portion, a portion next to the fixed leg forming a “heel”, and another reversely curved portion And finally another part forming a "toe" next to the fixed leg. Such clips are referred to below as "right-hand" clips. Another form of clamp, hereinafter referred to as a "left hand" clamp, is a mirror image of the right hand clamp and is made so that the fixing legs can be inserted into opposite ends of the fixing device.

The "e" clip and its replacement "PR" clip disclosed in British Patent GB 86 1473 provide safe and secure rail fastening and are therefore widely used. However, it has been found in some areas that a thief or vandal can remove the clip from the fixture, which is clearly undesirable. In order to prevent this kind of guide rail fastener from being destroyed without authorization, the applicant proposed in British Patent GB 2085057B that a step is arranged on the "spring heel" part of the clip, which is used to lean against a fixed On the stop on the peripheral portion of the device, the "spring heel" of the clip is to be driven past the stop when the clip is installed in the fixture. This solution makes it impossible for unauthorized persons to easily remove the clip from the fixture. However, increased force is required to extract the clip from the assembly, and it also increases the difficulty of replacing a clip that has been installed in the assembly and has been used for a long time so that it becomes damaged. In addition, this scheme cannot completely prevent being stolen. Because it has been found that although attempts to remove the clip by hammering alone can be prevented, if a crowbar (or even a stone) is first used to disengage the "spring heel" of the clip from the stop on the fixture, it can still be removed. Remove the clip. For this reason, the applicant aims to provide a more firm guide rail fastening assembly than British Patent GB 2085057B.

Contents of the invention

According to a first aspect of the present invention, there is provided a resilient railroad rail fastening clip for fastening a railroad rail to a base, the clip being a clip with a fixed leg for securing the clip to the rail Clamped by a fastening clip fixture, the clip has a mechanism for preventing unauthorized removal of the clip from the fixture, wherein the mechanism includes: A first locking structure on a spaced area, which is used to cooperate with a second locking structure disposed in the housing of the fixing device when the fixing leg is inserted into the fixing device, the first locking structure includes an abutment surface and a One of the protrusions, the second locking structure includes an abutment surface and the other one of the protrusions.

According to a second aspect of the present invention, there is provided a railway guide rail fastening clip fixing device for clamping the elastic railway guide rail fastening clip according to the first aspect of the present invention. The fixing device includes a housing with a channel for receiving the fixing leg of the clip, and the second locking structure is arranged in the channel to cooperate with the first locking structure configured on the fixing leg of the clip. Cooperate so that the clip cannot be seen outside the housing after being placed in the housing, the first locking structure includes one of an abutment surface and a protrusion, and the second locking structure includes either another.

In this way, the clip of the first aspect of the present invention can be placed in the fixing device of the second aspect of the invention in a simple and reliable manner, and it does not significantly increase the force required to remove the clip from the fixing device, But it can reduce the risk of being dismantled without authorization and increase the firmness of fastening.

Unlike the assembly disclosed in British Patent GB-2085057B, the mechanism of the present invention for preventing unauthorized removal of the clip is arranged invisibly within the fixture housing so that it is quite unobtrusive to a speculative thief. Or vandals showing signs of how to remove the clip. Conversely, if an attempt is made to use a crowbar that has been used in the past, the rock will dislodge the clip of the present invention from the fixture of the present invention, which will even cause the clip to be held more firmly in the fixture.

A clip to which the present invention is applied is preferably, but not necessarily, an "e" clip or a "PR" clip. It should be noted that no adjustments to the overall shape of the clip, such as the length of its securing legs, are required in order to employ the invention.

After installation, the stresses in the "e" or "PR" clips are higher (approximately 75% of the maximum stress on the clip) where an anti-vandal feature has been conventionally configured on the -80%). Therefore, as disclosed in British Patent GB-2085057B, a step (related to the shape and size of the set step) placed on the "spring heel" of the clip can cause a higher maximum in this area than the rest of the clip. Stress thus becomes one of the key factors for clamp function. In contrast, the stresses in the region near the end of the fixing leg are negligible, so that the stress concentration effect of providing the first locking structure on the fixing leg of the clip is insignificant.

It is recommended that the first locking structure comprises an abutment surface such as an inclined surface of a groove, in which case the second locking structure comprises a protrusion. Alternatively, the second locking structure comprises an abutment surface such as an inclined surface of a groove, in which case the first locking structure comprises a protrusion.

The angle of inclination of the inclined surface relative to the longitudinal axis of the fixed leg/channel is desirably in the range of 20°-90°.

The angle at which the abutment is inclined largely determines the force required to pull the clip out of the fixture. In some railroad systems, clip removal machines are used to pull conventional clips out of their fixtures. Therefore, if such a machine is used to extract the clip of the first aspect of the present invention from the fixture of the second aspect of the invention, the angle of inclination of the abutment surface should be chosen such that the force required to pull the clip out While higher than conventional fastening assemblies, the force should not damage the machine or damage the fastening members during pulling of the machine. In this case, a relatively small angle of eg 30° is suitable.

If it is required to prevent thieves and damage to a greater extent, the inclination of the abutment surface should be steeper (for example, greater than 40°), but it is basically impossible for traditional clip removal machinery to be used to pull this clip.

A special tool can be used to apply a downward force on the free end of the clamp's fixing leg, visible at the channel end of the fixing device housing, to disengage the first locking structure on the clamp's fixing leg from disposition. It is removed in the second locking structure in the housing and at the same time the clip is pulled out of the fixing device. It is convenient to use the tool if the housing is such that at least a part of the free end of the fixing means of the clip is exposed except for its end face when mounted in the housing.

With conventional clips such as "e" clips or "PR" clips, it can be difficult to ensure that the clip is installed in the correct position. If the clip is packed too far into the housing, there may be contact between other parts of the clip and the fixture than contact between the top of the fixture leg and the interior of the fixture. Such unintended changes in contact can result in undesirably high "toe" loads and stresses in the clip.

According to a third aspect of the present invention, there is provided an elastic railway guide rail fastening clamp for fastening a railway track to a base, wherein the clamp has a stop structure, which is used for fastening with a guide rail. Cooperating features on the clip fixture engage, thereby preventing the clip from being pushed too far into the fixture. The stop structure includes one of an abutment surface and a protrusion, and the matching structure includes the other of an abutment surface and a protrusion.

According to the fourth aspect of the present invention, there is provided a guide rail fastening clamp fixing device for clamping the elastic railway guide rail fastening clamp of the third aspect of the present invention, wherein the device has a An engaged mating structure, the stopper structure includes one of an abutment surface and a protrusion, and the mating structure includes the other of an abutment surface and a protrusion.

Thus, the clip embodying the third aspect of the invention can be correctly positioned in the housing of the fixture embodying the fourth aspect of the invention.

The stop structure may comprise an abutment surface, in which case the cooperating structure comprises a protrusion. As an alternative, the stop structure may comprise a protrusion. In this case, the matching structure has an abutment surface. The abutment surface can be provided by a surface of a groove, and it is desirable that the inclination angle of the abutment surface relative to the installation direction of the clip is in the range of 35°-90°, and the recommended angle value is about 90°.

If the clip is the kind that has a fixed leg, and the clip is clamped by the fixing device accordingly, then the stop structure can be arranged on the fixed leg, and its matching structure can be configured in the fixture housing.

In order to avoid the problem of overfitting in the clip of the first aspect of the invention or in the fixing device of the second aspect of the invention, the groove (the groove may constitute the first or second locking structure as the case may be) ) may have another inclined surface which is inclined in the opposite direction to the other inclined surfaces. The inclination angle and position of the other inclined surface are configured to prevent excessive loading of the clip into the fixture. The desired value of the inclination angle of the other inclined surface relative to the longitudinal axis of the fixed leg/channel is in the range of 35°-90°, and the recommended value is about 90°. The foot of the other slope may be spaced from the foot of the other slope.

Description of drawings

The correlation will now be explained by way of example in conjunction with the accompanying drawings, each of which is:

Figure 1A shows a plan view of a prior art elastic railway rail fastening clip;

Figure 1B shows a partial side sectional view of a railroad rail fastening assembly for use with the clip shown in Figure 1A;

Figure 2 shows a partial cutaway end view of the railway rail elastic fastening clip and fixing device of the present invention;

Fig. 3 shows the side cross-sectional view of a part of the railway rail elastic fastening clip and fixing device of the present invention;

Fig. 4 shows the partial sectional view of another kind of railway guide rail fastening clip and fixing device of the present invention;

5A, 5B, and 5C are partial side sectional views showing the embodiment in FIG. 4 respectively, and they are used to illustrate how the clip can be detached from the fixing device;

Figure 6A shows a partial end view of another guide rail fastening (clip) fixture of the present invention, and Figure 6B is a partial cross-sectional view taken along the section line A-A in Figure 6A;

7A shows a partial side view of the rail fastening clip of the present invention for use in conjunction with the fixing device of FIGS. 6A and 6B, and FIG. 7B is a partial cross-sectional view taken along line A-A of FIG. 7A.

Detailed ways

The prior art railroad rail elastic fastening clip 10 shown in FIG. 1 is an "e"-shaped clip. The clip 10 is made by bending a metal rod, which is depicted sequentially from one end A to the other B of its end A to have a first substantially straight portion, the fixed leg 11, followed by a second oppositely bent portion 12 , a third portion 13 , a fourth reversely curved portion 14 and finally a fifth portion 15 . When clip 10 is designed as shown structure, the lowermost part of its third and fifth parts are in the same plane, and when clip 10 is viewed directly from above or below this plane, the third and fifth parts are in its first position. Part 11 of the opposite side. Although not shown in the description of this application, so-called "PR" type clips have a similar shape.

Both the "e" type clip and the "PR" type clip can be gripped by a metal cast rail fastening clip fixture as shown in FIG. Either the third part or the fifth part) is supported on the adjoining rails. Only one pair of fixtures 100 that may be used in rail fasteners is shown in FIG. 1B . The fixing device 100 is fastened to the rail base, in this case a concrete tie 2, by feet 101 embedded in the cement. The leg 101 is connected to the housing 102 of the fixing device 100 , and the housing 102 has a through passage 103 . The guide rail 1 has a foot 1a, the guide rail 1 is placed on the vibration-absorbing guide rail pad 4 between the pair of shoulders 100, and a guide rail isolator 3 is placed on the guide rail foot 1a. The fixed leg 11 of the rail clip 10 is loaded into the channel 103 and deflects the clip 10 so that the "toe" portion of the clip (in this case the fifth portion) passes a desired force through the rail spacer 3 applied to the rail foot 1a. The "spring heel" portion (in this case the third portion) of the clip 10 rests against a leg portion 104 of the housing 102 . An upper surface of the fixed leg 11 is held in contact with the top of the channel 103 .

Although not shown in FIG. 1A , the fixing leg 11 of the clip 10 may be beveled at its free end to facilitate insertion of the fixing leg 11 into the channel 103 of the fixing device 100 .

Although the present invention may be applied to any type of railroad track resilient fastening clip having a fixed leg whereby the fastening means retains the clip, the present invention will only be described in connection with the application of the "e" type clip.

FIG. 2 shows a fixing leg 21 of the rail fastening clip 20 of the first aspect of the present invention. Although the entire rail clip 20 is not shown, the rest of it outside of the fixed legs 21 is similar to, for example, an "e" clip, a "PR" clip or the like. The fixed leg 21 has a bevel 21b at its free end A. As shown in FIG. Moreover, the first locking structure disposed at a distance from the free end has a detent, that is, a groove 21a, which (21a) has an abutment surface 21c. A fastening device, namely a shoulder 200 (not shown in full view) for clamping the rail fastening clip 20 has a housing 202 in which a through passage 203 is formed. On top inside the channel 203 there is a second locking structure comprising a protrusion 203a. The first and second locking structures work together to form a mechanism that prevents the clip 20 from being removed from the fixing device 200 without authorization. Other parts of the fixation device may be similar to that of the fixation device 100 shown in FIG. 1B . The detents 21a may be punched into the fixed legs of the clip 20 during or after the clip is made. The protrusion 203a is formed during the manufacture of the fixing device 200 .

The difference between the embodiment shown in FIG. 3 and that shown in FIG. 2 is that the rail fastening clip 30, not shown in its entirety, has a fixed leg 31 with a beveled angle 31b, and it has a first locking structure including a protrusion 31a The fixing device 300 (not showing its whole picture) has a housing 302, which (302) has a passage 303, and a second locking structure is provided on the top of the passage 303, and this structure has a groove 303b with an abutment surface 303b .

When the fixing leg 21 (31) of the clamp 20 (30) of the present invention is inserted into the channel 203 (303) of the fixing device of the present invention, the projection 203a is on the fixing leg 21, especially on the bevel 21b or The pressure of the protrusion 31a on the top of the channel 303 forces the clip to deflect slightly downwards and continues until the fixed leg 21 (31) reaches a position where the first and second locking means are snap-engaged with each other as shown in FIG. 4 until.

To deter theft and vandalism, the locking structure should be sized and positioned such that substantial movement of the securing leg is necessary to remove the clip, but such movement does not cause permanent deformation of the clip.

Depending on whether a "right hand" or a "left hand" type clip is used, it is desirable to determine which end of the passageway the locking structure (feature) of the fixture is placed near. If it is desired to enable the fixture to be used with either a "left hand" or "right hand" type clip, then its locking structure can be located at the center of the fixture. In this case, due to the increased angle subtended by the top of the protrusion, it becomes more difficult to actuate the associated clip.

Fig. 4 shows another embodiment of the invention based on the embodiment shown in Fig. 2, but the fixing device 400 has a modified housing 402 which (402) has a channel 403 and a protrusion 403a. The other end of housing 403 is enlarged, thereby makes the one end portion of channel 403 adjacent to projection 403a be cut off so that there is a flaring hole 404, thereby makes the upper surface of the free end A of fixed leg 21 be exposed, so that A special clip removal tool (described in more detail below in connection with Figures 5A, 5B and 5C) enters it. It can be seen from FIG. 4 how the protrusion 403 a abuts against the abutment surface 21 c of the fixed leg 21 , thereby hindering the removal of the clip. Compared to some prior art, the clip 20 (30) of the present invention can be made such that it cannot be easily removed from the fixture 200 (300, 400) of the present invention by a blow of a hammer in the R direction. Remove it. Rather, in order to remove such a clip 20 (30), downward pressure must be applied to the free end A of the fixed leg to deflect the fixed leg downward so that the protrusion 403a (203a, 31a) is free from abutment The face 21c (303b) is disengaged and the clip is driven in the direction R at the same time.

As can be seen from Figures 5A, 5B and 5C, removal of the clip can be accomplished using a specially designed tool 70 having a front end 71 . The front end 71 of the tool 70 is shaped to be inserted into a flared hole between the upper surface of the free end A of the fixed leg 21 ( FIG. 5A ) of the clamp 20 and the housing 402 . As the front end 71 of the tool 70 is further pushed into the flaring hole 404, the free end A of the fixed leg 21 of the clip 20 is gradually pushed downward, so that the catch 21a is disengaged from the protrusion 403a and is attached to the tool. Table 72 of 70 contacts (FIG. 5B), and then fixed leg 21 can be pushed along channel 403 (FIG. 5C).

As shown in the above embodiment, the first and second locking structures of this embodiment have an abutment surface and a protrusion, and one of the clip or the fixing device may have an abutment surface. From a manufacturing point of view, however, it is more desirable and easier to manufacture to provide the clamping part with an abutment surface and the fixing means with projections, for example by means of a detent.

Although the above-mentioned embodiment of the present invention has adopted a cast fixture, the present invention can also be applied to a press-worked steel fixture, as described below in conjunction with accompanying drawings 6A, 6B and 7A, 7B ; Or it can also be used for a fixture (not shown) made of rolled steel sheet.

As shown in Figures 6A and 6B, a press-worked steel fixture 500 has a housing 502 shaped to have a through passage 503 with the top of the passage 503 at one end adjacent to but not far from the end. A second locking structure having a protrusion 504 formed by forming a groove on the top of the housing 502 is disposed at an alternate position. The protrusion 504 can be seen more clearly in FIG. 6B , which shows a cross-sectional view of the top of the housing 502 parallel to the channel 503 . The shape and size of the protrusion 504 depend on the shape and size of the abutting surface that cooperates with it. In the thick 10 mm shell 502, the length of its channel 503 is 70 mm, and its protrusion 504 can be made at 45 mm from one end of the channel 503. It is made to be 2 mm high and 5 mm wide. The radius of curvature is 3 mm.

Figures 7A and 7B illustrate the fixed leg 51 of the rail fastening clip 50 (not shown in its entirety) of the first and third aspects of the invention, the clip 50 being similar in many respects to the clip in Figures 2, 3 and 4. The fixed leg 51 has a chamfer at its free end A and at a short distance from the free end A has a detent or groove 51a. The groove 51a has two abutment surfaces 51c and 51d, which (as viewed along the order of the fixing leg 51 away from the free end A) extend downward and upward, respectively. In this embodiment, the upwardly extending surface 51d is more inclined than the downwardly extending surface 51c. In the present embodiment shown, with respect to downwardly extending surface 51c, its angle relative to the longitudinal axis of fixed leg 51 is about 30°; and the angle toward the top of upwardly extending surface 51d is about 90°, which is The base has a radius 1R.

In the clip embodiment shown in Figures 7A and 7B, the groove 51a is made such that its edge closest to the free end A of the leg 51 is 10 mm from the end A, and its (51a) is along the leg 51. The length in the direction of extension is 12.5 mm and the depth is 2 mm. The base radius of the upwardly extending surface 51d is 1 mm.

In the previously described embodiment, the surface of the groove which abuts against the protrusion and which is intended to hinder disassembly of the clip is substantially vertical. Therefore, it is very difficult to remove the clip in the usual way. However, in the embodiment shown in Figures 6A, 6B, 7A and 7B, the downwardly extending surface 51c is inclined at a relatively small angle. Obviously, such a clamp still provides a much greater resistance to unauthorized disassembly than a clamp without locking means, but the resistance provided is still relatively small because the abutment surface 51c passes over the protrusion 504. Movement requires less force. Nevertheless, the force required in this case is still sufficient to prevent the clip 50 from moving out of the fixture 500 as it becomes worn in use.

If it is desired to hinder the removal of the clip more, the abutment surface 51c can have a steeper angle of inclination, preferably greater than 40°.

The angle of inclination of the upwardly extending surface 51d can also vary, but in the embodiment shown in FIGS. When the device 500 is in place, the stopper comes to abut against the protrusion 504, thereby ensuring that the clip 50 cannot be easily pushed past its correct installation position in the set working position. Specifically, by configuring a suitable steep upwardly extending surface 51d with an angle of inclination in the range of 35-90° relative to the longitudinal axis of the fixed leg 51 at a suitable position, it is possible to make the clamp when the clip is installed in the correct position. The sudden increase in force required to drive the clip prevents the clip from being over-loaded.

A clip that adopts the present invention is configured with a detent as shown in Figure 2 on its fixed leg (instead of configuring a protrusion as shown in Figure 3), and it can be used in existing, not adopting the present invention in the fixture. This would allow the railroad system to maintain an inventory of only one type of clip that would take advantage of the added benefits of fixtures embodying the present invention, but be combined with conventional clips and existing fixtures that do not employ the present invention Compared with the situation, the defects are eliminated.

In an assembly designed to provide maximum resistance to disassembly, the shape of the fixture has been modified to allow removal of the fixture with specialized tools. Another advantage is conceivable: where rust in the fixture would become one question. Prior art clips cannot be easily removed from the fixture if corroded. However, if the fixing device with a cut-off part as shown in Figure 4 is adopted, downward pressure can be easily applied to the free end of the clamp fixing leg, thereby easily breaking the gap between the clamp and the fixing device. of adhesion. This is of greatest advantage if the fixture has a D-shaped cross-section (rather than a circular) passage, since it provides more space for the deflection of the fixture legs of the clip into it.

Claims (18)

1. one kind is used for railroad rails is anchored on elasticity railroad rails anchorage clip on the pedestal, this folder is a kind of folder with a fixed supporting leg, it is used for making double-layered quilt guide rail anchorage clip fastening devices clamping, this folder has and is used for hindering without permission folder from mechanism that fastening devices is pulled down, wherein, this mechanism comprises: be configured on the fixed supporting leg with this supporting leg free end zone at interval on first latch-up structure, this structure is used for when fixed supporting leg is inserted into fastening devices and the second latch-up structure mating reaction that is configured in the fastening devices housing, first latch-up structure comprises in an abutment face and the projection, and second latch-up structure then comprises another in an abutment face and the projection.

2. folder as claimed in claim 1, it is characterized in that, this folder comprises a rod member that is bent into by elastomeric material, be followed successively by to its another free end B from a free end A of bar, one first of this fixed supporting leg of formation of straight line substantially, the about 180 ° second portion of one bending, one places the other third part of first's side, one bends 180 ° the 4th part substantially, and last one place the 5th other part of first's side, this folder is configured to when it is positioned arrangement, the 3rd, minimum point on five parts is in the same plane, and above or below this plane, rightfully observe when pressing from both sides the 3rd, five parts are positioned at the opposite both sides of first significantly.

3. folder as claimed in claim 1 or 2 is characterized in that, this abutment face is that the inclined plane by a groove provides.

4. folder as claimed in claim 1 is characterized in that, the angle of slope of the longitudinal axis of this abutment face relative fixed supporting leg is 20 °-90 °.

5. folder as claimed in claim 4 is characterized in that, this angle of slope is 30 °.

6. folder as claimed in claim 4 is characterized in that this angle of slope is greater than 40 °.

7. folder as claimed in claim 3, it is characterized in that, this groove has a relative righrts requirement 3 described inclined planes and does another inclined plane that rightabout tilts, and the position on this inclined plane and angle of inclination are set up to such an extent that can prevent that folder is by in the fastening devices of packing into too much.

8. folder as claimed in claim 7 is characterized in that, the angle of slope of the longitudinal axis of described another inclined plane relative fixed supporting leg is 35 °-90 °.

9. folder as claimed in claim 7 is characterized in that, the foot on the foot on this another inclined plane and the described inclined plane of claim 3 is spaced apart.

10. one kind is used for the guide rail anchorage clip fastening devices of the described elasticity railroad rails of the arbitrary claim in clamping front anchorage clip, this fastening devices comprises that one has the housing of a passage, passage is used for admitting the fixed supporting leg of folder, wherein, second latch-up structure is configured in this passage, first latch-up structure that is used for and is configured on the fixed supporting leg of folder is used, thereby first fixed structure can not be in sight from this hull outside when folder is loaded in the housing, first latch-up structure comprises in an abutment face and the projection, and second latch-up structure then comprises another in an abutment face and the projection.

11. fastening devices as claimed in claim 10 is characterized in that, this abutment face is that the inclined plane by a groove provides.

12. fastening devices as claimed in claim 10 is characterized in that, the angle of slope of the longitudinal axis of the relative passage of this abutment face is 20 °-90 °.

13. fastening devices as claimed in claim 12 is characterized in that, this angle of slope is 30 °.

14. fastening devices as claimed in claim 12 is characterized in that, this angle of slope is greater than 0 °.

15. fastening devices as claimed in claim 11, it is characterized in that, this groove also has a relative righrts requirement 11 described inclined planes to do another inclined plane that rightabout tilts, and the position on this inclined plane and angle of inclination are configured to prevent that folder is by in the fastening devices of packing into too much.

16. fastening devices as claimed in claim 15 is characterized in that, the angle of slope of the longitudinal axis of the relative passage in described another inclined plane is 35 °-90 °.

17. fastening devices as claimed in claim 15 is characterized in that, the foot on the foot on this another inclined plane and the described inclined plane of claim 12 is spaced apart.

18. fastening devices as claimed in claim 10, it is characterized in that, when this housing was provided in double-layered quilt and is fit into fastening devices, at least a portion except that free end face of fixed supporting leg that makes folder was by exposed, thereby allowed to exert pressure thereon with a specialist tools.

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