JP4592979B2 - Fastening method of brake disks for railway vehicles - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for fastening a railway vehicle brake disc, and more particularly to a fastening method suitable for an aluminum matrix composite disc.
[0002]
[Prior art]
There are two types of disc brakes for railway vehicles: wheel-side mounted types and axle-mounted types. Wheel side-mounted disc brakes use the space on the wheel side to store the brake discs in this space. Because of the method, it can be a compact design. In addition, cast steel, forged steel, cast iron, and aluminum-based composite materials are used as brake disc materials, and brake discs made of aluminum-based composite materials are lightweight and have excellent sliding characteristics. is doing. The aluminum-based composite material is obtained by dispersing particles and fibers such as SiC ceramic in an aluminum alloy.
[0003]
FIG. 3 shows an example of a conventional wheel side mounted disc brake. In this disc brake, a pair of brake discs 52 are overlapped on both side surfaces of the wheel 51, and the fastening holes 53, 54 provided on the wheel 51 and the brake discs 52 are aligned, and the fastening holes 53 are aligned. The brake discs 52 are fastened to the wheels 51 by means of fastening bolts 55 and fastening nuts 56 inserted into the wheels 51. A flat sliding surface 57 is provided on the front surface side of each brake disk 52, and fins 58 for heat dissipation are provided on the back surface side, and brake pads (not shown) are pressed from both sides of each sliding surface 57. ing.
[0004]
The brake discs 52 are formed of an aluminum-based composite material that is softer than steel, and each brake disc 52 includes a flat washer 59 and the like so that the fastening parts made of steel do not bite into the surface by the fastening force at the time of fastening. It is clamped via a disc spring washer 60 having an elastic restoring force.
[0005]
Further, the shaft portion of the fastening bolt 55 is formed with a smaller diameter than the fastening hole 54 of the brake disc 52 in anticipation of thermal expansion allowance of the brake disc 52 due to frictional heat generation at the time of brake operation. A straight portion 61 that fits into the fastening hole 53 of the wheel 51 is provided, and the fastening bolt 55 is positioned and fixed to the wheel 51.
[0006]
When fastening the pair of brake discs 52 to the wheels 51, first, in a state where the fastening holes 53, 54 of the wheels 51 and the brake discs 52 are aligned, A separate positioning tool such as a gauge pin or a positioning bolt is fitted into the brake disk 52 so that the center of each brake disk 52 is positioned. Thereafter, the fastening bolt 55 is inserted into each of the remaining pairs of fastening holes 53 and 54, and a fastening nut is inserted. 56, the positioning tool used for center positioning is pulled out, and the fastening bolts 55 are inserted into the fastening holes 53 and 54 from which these positioning tools have been pulled out, thereby fastening the fastening nut 56.
[0007]
[Problems to be solved by the invention]
The above-described conventional method for fastening a brake disc for a railway vehicle has a problem that a separate positioning tool is required for centering the brake disc.
[0008]
In addition, the washer used for fastening has a center hole formed larger in diameter than the shaft portion of the fastening bolt and is eccentric about the shaft portion, so that the washer is unevenly contacted with the surface of the brake disk, When a brake disc made of an aluminum matrix composite is used, there is a problem that the surface pressure of the unevenly contacting portion becomes high and the washer bites into the surface of the brake disc. This eccentricity of the washer also causes the rotational balance of the wheel to be out of order when the brake disk is removed and returned for testing or the like.
[0009]
Therefore, an object of the present invention is to enable center positioning at the time of fastening of a brake disk for a railway vehicle without using a separate positioning tool, and to prevent eccentricity of a washer used for fastening.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a pair of brake discs on both sides of a wheel of a railway vehicle so that each of the wheels and each brake disc has an equal-diameter fastening hole. Align, insert a fastening bolt into each of the aligned fastening holes, screw a fastening nut to the tip of the fastening bolt, and between the fastening bolt head and one brake disc, and the fastening nut In a method for fastening a brake disc for a railway vehicle in which a pair of brake discs are fastened to wheels by interposing a washer between the other brake discs, at least two, preferably three or more of the fastening bolts. Positioned and combined fastening with a straight part that fits the fastening holes of the same diameter at the neck lower part and the shaft center part, each with a predetermined length. The plurality of positioning and combined fastening bolts are inserted into the plurality of fastening holes of the overlapped wheel and the pair of brake discs up to the lower neck portion, and the straight portion of the lower neck portion is inserted into the fastening bolt head side. Is fitted to the fastening holes of the brake disc, the straight portion of the central portion of the shaft is fitted to both fastening holes of the brake disc on the wheel and the fastening nut side, and the center positioning of the pair of brake discs is performed, By inserting a fastening bolt into each of the above-mentioned aligned fastening holes in which these positioning and fastening bolts are not inserted, and tightening these fastening bolts with a washer between the head side and the fastening nut side. The pair of center-positioned brake discs are fixed to the wheels, and then the positioning and fastening bolts are removed from the fastening holes. Then, insert each of these positioning / use fastening bolts with a washer on the head side and insert it again into each of the extracted fastening holes, and also place a washer on the side of the fastening nut to attach the pair of brake discs. When fastening, the straight portion at the lower part of the neck of each positioning / fastening bolt is retracted from the fastening hole of the brake disc on the fastening bolt head side, and the straight portion at the center of the shaft is moved to the brake disc on the fastening nut side. The method of retracting from the fastening holes and fitting only into the fastening holes of the wheels is adopted.
[0011]
In other words, at least a plurality of fastening bolts are superposed as positioning and fastening bolts each having a predetermined length with a straight portion that fits in each of the equal diameter fastening holes in the lower neck portion and the shaft center portion. Insert these positioning bolts into the fastening holes of the pair of brake discs up to the bottom of the neck. Insert the straight part at the bottom of the neck into the fastening hole of the brake disc on the fastening bolt head side and the straight part at the center of the shaft. The center of each brake disc is positioned by fitting it into both the fastening holes of the wheel and the brake disc on the side of the fastening nut, and this pair of centered brake discs are fastened with the other fastening holes that are aligned. After that, when fastening the brake disc, the lower part of the neck and the straight part of the central part of the shaft are connected to the fastening bolt head side. By retracting from the fastening hole of the brake disc on the fastening nut side, the thermal expansion allowance is secured in the fastening hole of each brake disc, and each brake disc can be positioned at the center without using a separate positioning tool. .
[0012]
The center hole of the washer on the positioning and fastening bolt head side has the same diameter as the fastening hole, and a straight portion that fits into the center hole of the washer on the fastening nut side is provided at a tip of the positioning and fastening bolt. When the pair of brake discs are fastened with each of these washers interposed, the straight part of the lower neck is fitted into the central hole of the washer on the bolt head side, The straight portions are fitted into the center holes of the washers on the side of the fastening nuts and retracted from the fastening holes of the brake discs on the side of the fastening nuts. Can be prevented.
[0013]
By interposing another washer having an elastic restoring force on the outer surface side of each of the fastening bolt head side and the fastening nut side, an excessive tightening force is not generated when the brake disc is fastened, and the brake disc is Even when an aluminum matrix composite material softer than steel is used, the washer can be prevented from getting into the brake disk surface.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a railway vehicle disc brake to which a brake disc fastening method according to the present invention is applied. In this disc brake, a pair of brake discs 2a and 2b are overlapped on both side surfaces of the wheel 1, and the positioning and fastening bolts 5 inserted through the fastening holes 3 and 4 provided in the wheel 1 and the brake discs 2a and 2b, respectively. Each brake disc 2 is fastened to the wheel 1 by a fastening nut 6. A flat sliding surface 7 is provided on the front surface side of each brake disk 2a, 2b, and a heat radiating fin 8 is provided on the back surface side so that the brake pad 9 is pressed from both sides of each sliding surface 7. Yes.
[0015]
The brake discs 2a and 2b are made of an aluminum-based composite material that is softer than steel, and the surfaces of the brake discs 2a and 2b are so formed that the fastening parts made of steel do not bite into the surface due to the fastening force at the time of fastening. In addition to the flat washer 10, it is tightened via two disc spring washers 11 having elastic restoring force so that an excessive tightening force is not generated.
[0016]
As shown in FIG. 2A, the positioning and fastening bolt 5 has a fastening nut 6 screwed to a screw portion 12 provided at the tip portion, and a tip portion on the shaft center portion, a neck lower portion, and the screw portion 12 side. The straight portions 13a, 13b and 13c are provided in the respective portions, and the small diameter portions 14a and 14b are provided between the straight portions 13a, 13b and 13c. The fastening nut 6 is provided with a notch 15, and a locking pin 16 for preventing rotation is inserted from the notch 15.
[0017]
The straight portions 13 a, 13 b, and 13 c are fitted in the fastening holes 3 of the wheels 1 formed to have the same diameter and the center holes of the plain washers 10, and the positioning and fastening bolts 5 are positioned on the wheels 1. While being fixed, each flat washer 10 is fixed so as not to be eccentric around the shaft portion of the fastening bolt 5. Further, the small diameter portions 14a and 14b are inserted into the fastening holes 4 of the brake disks 2a and 2b, and a gap as a thermal expansion allowance is provided between the fastening holes 4 and the shaft portions of the positioning and fastening bolts 5. Is formed.
[0018]
Below, the procedure of fastening each brake disk 2a, 2b to the wheel 1 using the positioning and combined fastening bolt 5 will be described. First, in a state where the wheel 1 and the fastening holes 3 and 4 of the brake discs 2a and 2b are aligned, as shown in FIG. The combined fastening bolt 5 is inserted to the lower part of the neck, the straight part 13b of the lower part of the neck is fitted into the fastening hole 4 of the brake disk 2a, and the straight part 13a of the central part of the shaft is connected to the fastening hole 3 of the wheel 1 and the brake disk 2b. The center of each brake disk 2a, 2b is positioned by fitting in both of the fastening holes 4. The fastening holes 3 and 4 used for the center positioning can be, for example, every other one of a plurality of holes formed in the circumferential direction of the wheel 1 and the brake disks 2a and 2b.
[0019]
Next, the other positioning / fastening bolts 5 are inserted into the fastening holes 3 and 4 other than the fastening holes 3 and 4 into which the positioning / fastening bolts 5 are inserted to the lower part of the neck, as shown in FIG. As described above, the fastening nut 6 is tightened with the plain washer 10 and the disc spring washer 11 interposed between the head side of the positioning and fastening bolt 5 and the fastening nut 6 side.
[0020]
Further, with respect to the fastening holes 3 and 4 used for the center positioning, once the positioning and fastening bolts 5 inserted to the lower part of the neck are extracted, the plain washers 10 and As shown in FIG. 2A, the disc spring washer 11 is interposed and reinserted into the extracted fastening holes 3 and 4, and the plain nut 10 and the disc spring washer 11 are also interposed on the fastening nut 6 side. Then, the fastening nut 6 is tightened. At this time, as described above, each flat washer 10 is fixed so as not to be eccentric by the neck lower portion and the straight portions 13b and 13c of the tip portion of the positioning and fastening bolt 5.
[0021]
In the embodiment described above, all fastening bolts are used as positioning and fastening bolts in order to provide compatibility of parts. However, only a plurality of bolts necessary for positioning of the brake disk are used as positioning and fastening bolts, and others. A fastening bolt similar to the conventional one can also be used.
[0022]
In addition, although the brake disc is made of an aluminum-based composite material, the method of fastening the brake disc according to the present invention can also be applied when using a steel brake disc. In this case, only the plain washer is used as a washer. It is good.
[0023]
【The invention's effect】
As described above, the method of fastening a brake disc for a railway vehicle according to the present invention includes fastening at least a plurality of fastening bolts with equal diameters provided on a wheel and a pair of brake discs at a lower neck portion and a shaft central portion. As positioning and fastening bolts each provided with a straight portion that fits into the hole with a predetermined length, these positioning and fastening bolts are inserted into the fastening holes of the wheel and the pair of brake disks that are overlapped to the bottom of the neck, Position the center of each brake disc by fitting the straight part at the bottom of the neck into the fastening hole of the brake disc on the fastening bolt head side and the straight part at the center of the shaft into the fastening holes on the brake disc on the wheel and fastening nut side. The pair of brake disks positioned at the center are fixed to the wheel with fastening bolts at the other fastening holes aligned with each other. That is, when the brake disc is fastened, the straight portions of the neck lower part and the shaft center part are retracted from the fastening holes of the brake disk on the fastening bolt head side and the fastening nut side, respectively. The brake disk can be positioned at the center without using.
[0024]
The center hole of the washer on the positioning and fastening bolt head side has the same diameter as the fastening hole, and a straight portion that fits into the center hole of the washer on the fastening nut side is provided at a tip of the positioning and fastening bolt. When the pair of brake discs are fastened with each of these washers interposed, the straight part of the lower neck is fitted into the central hole of the washer on the bolt head side, The straight portions are fitted into the center holes of the washers on the side of the fastening nuts and retracted from the fastening holes of the brake discs on the side of the fastening nuts. Can be prevented.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing a railway vehicle disc brake to which a brake disc fastening method according to the present invention is applied. FIG. 2 is an enlarged view of a main part of FIG. Fig. 3 is a longitudinal sectional view showing an enlarged main part of a conventional railway vehicle disc brake.
DESCRIPTION OF SYMBOLS 1 Wheel 2a, 2b Brake disk 3, 4 Fastening hole 5 Positioning combined use bolt 6 Fastening nut 7 Sliding surface 8 Fin 9 Brake pad 10 Flat washer 11 Belleville spring washer 12 Screw part 13a, 13b, 13c Straight part 14a, 14b Small diameter Part 15 notch 16 pin

Claims (3)

A pair of brake discs are overlapped on both sides of the wheels of the railway vehicle, and the equal diameter fastening holes respectively provided on the wheels and the brake discs are aligned. Insert the fastening bolt, screw the fastening nut onto the tip of the fastening bolt, and place a washer between the head of the fastening bolt and one brake disc, and between the fastening nut and the other brake disc. Then, in the method for fastening a brake disc for a railway vehicle, in which a pair of brake discs are fastened to wheels, at least two of the fastening bolts are connected to the lower part of the neck and the central part of the shaft with the same diameter. The straight portion that fits into each fastening hole is a positioning / fastening bolt provided with a predetermined length, and the plurality of positioning / fastening bolts are overlapped with each other. Inserted into the plurality of fastening holes of the wheel and the pair of brake discs up to the lower part of the neck, and the straight part of the lower part of the neck is fitted into the fastening hole of the brake disc on the fastening bolt head side, and the shaft center part The straight portion is fitted into both the fastening holes of the wheel and the brake disc on the side of the fastening nut, the center positioning of the pair of brake discs is performed, and the other positions where these positioning and fastening bolts are not inserted By inserting fastening bolts into the respective fastening holes and fastening these fastening bolts with a washer between the head side and the fastening nut side, the pair of center-positioned brake disks are fixed to the wheels. After that, the positioning and fastening bolts are removed from the fastening holes, and the positioning and fastening bolts are placed on the head side with a washer. Then, when the pair of brake discs are fastened with a washer interposed on the side of the fastening nut, the straight portion at the lower part of the neck of each positioning / use fastening bolt is inserted into each of the extracted fastening holes. Retract from the fastening hole of the brake disk on the fastening bolt head side, and retract the straight part at the center of the shaft from the fastening hole of the brake disk on the fastening nut side to fit only in the fastening hole of the wheel. A method of fastening a brake disk for a railway vehicle, characterized in that it is configured as described above. The center hole of the washer on the positioning and fastening bolt head side has the same diameter as the fastening hole, and a straight portion that fits into the center hole of the washer on the fastening nut side is provided at a tip of the positioning and fastening bolt. When the pair of brake discs are fastened with each of these washers interposed, the straight part of the lower neck is fitted into the central hole of the washer on the bolt head side, The method for fastening a brake disc for a railway vehicle according to claim 1, wherein the straight portion is fitted into a center hole of a washer on the side of the fastening nut and retracted from the fastening hole of the brake disc on the side of the fastening nut. . 3. The brake disk according to claim 1 or 2, wherein the brake disc is formed of an aluminum-based composite material, and another washer having an elastic restoring force is interposed on each outer face side of each of the fastening bolt head side and the fastening nut side. To fasten brake discs for railway vehicles.

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