JP2008151188A - Railway vehicle brake linings and disc brakes - Google Patents

Abstract

Thermal energy generated during brake operation is evenly distributed on the inner and outer peripheral sides of a brake disc with a fastening hole interposed therebetween.
A brake lining 5 for a railway vehicle that is pressed against a disc body 4 attached to an axle 3 or a slide surface 2a of a brake disc 2 that is bolted to a wheel 1 at a fastening hole 2b provided in the slide surface 2a. is there. A friction member 5a pressed against the sliding surface 2a and a back plate 5b attached to the brake caliper and supporting the friction member 5a are provided. The friction member 5 a is divided and arranged in two or more in the radial direction of the brake disk 2. Each of the divided friction members 5a is arranged avoiding a concentric circle passing through the center of the fastening hole 2b. The friction member 5a is formed so that the center line 7 in the radial direction of the friction member 5a and the outline of the fastening hole 2b do not intersect during the brake operation.
[Effect] Since the maximum temperature of the brake disc is reduced, the occurrence of thermal deformation and cracking of the brake disc can be reduced.
[Selection] Figure 1

Description

  The present invention relates to a brake lining for a railway vehicle that effectively disperses thermal energy due to friction with the brake disk and improves durability of the brake brake mainly in a railway vehicle disk brake, and a disk brake including the brake lining. It is about.

  In land transport machines such as railway vehicles, automobiles, and motorcycles, disk brakes are increasingly used as braking devices with the increase in speed and size of vehicles.

  A disc brake is a device that obtains a braking force by friction between the brake disc and the brake lining, and obtains a braking force by pressing the brake lining against the sliding surface of the brake disc to brake the rotation of the axle or wheel. To control the vehicle speed.

  At this time, the temperature of the contact surface between the brake lining and the brake disc rises due to frictional heat, but the brake load increases and the temperature at the contact surface tends to increase as the vehicle speed increases or the vehicle weight increases.

  By the way, in a railway vehicle, there are a side disk and a shaft mount disk as the brake disk. Of these, the side disc is a brake disc 2 fastened to the side surface of the wheel 1 as shown in FIG. 3, and the shaft mount disc is fastened to a disc body 4 attached to the axle 3 as shown in FIG. Brake disc 2

  Hereinafter, in the present specification, the case of the side disk will be described, but it goes without saying that the same applies to the case of the shaft-mounted disk.

  FIG. 5 shows a brake lining and a brake disc as a conventional disc brake for a railway vehicle. 5A is a plan view of the brake lining as viewed from the friction member side, and FIG. 5B is a cross-sectional view taken along the line AB of FIG.

  The brake lining 5 has a configuration in which a friction member 5a that comes into contact with the brake disk 2 is attached to the back plate 5b by a rivet (not shown). The brake lining 5 is attached to a brake caliper (not shown).

  The brake caliper is a device for obtaining a braking force by pressing the brake lining 5 against the brake disc 2, and there are a hydraulic type and a pneumatic type. The pressing force applied to the brake lining 5 from the brake caliper does not act on the entire brake lining 5 due to the structure of the mounting portion, but acts on a specific part. For example, in the case of a hydraulic caliper, there are two pressing load center positions 6 as shown in FIG. 5, and even in the case of a pneumatic caliper, the pressing load is applied at substantially the same position.

  As described above, in the conventional disc brake, because of its structure, the pressing force from the brake caliper acts only on a part of the brake lining 5. For this reason, in the contact surface of the brake lining 5 and the brake disc 2, the difference between the portion with a high contact surface pressure and the portion with a low contact surface pressure becomes large, and immediately below where the pressing force from the brake caliper acts, the brake lining 5 and the brake disc 2 The contact surface pressure tends to increase.

  In the portion where the contact surface pressure is high, more heat energy is generated due to friction, and particularly in a high-speed vehicle such as a Shinkansen, there is a possibility that the temperature rise during the brake operation becomes excessive. If the contact surface pressure increases and the temperature rises, it may cause an increase in the amount of wear of the brake lining 5 and the brake disc 2 and the occurrence of cracks in the brake disc 2. Therefore, in order to ensure the durability of the brake lining 5 and the brake disc 2, it is important to efficiently disperse the heat energy due to friction between the two during the brake operation.

  In particular, in recent years, the shape and structure of the brake disc has been diversified along with the increase in the speed of the vehicle, and depending on the structure of the brake lining used, there is a possibility that the performance cannot be fully exhibited.

For example, Patent Document 1 discloses a brake disc that is bolted at a sliding portion, and this brake disc is provided with a fastening hole on a sliding surface that comes into contact with a brake lining (see FIG. 3). . Therefore, in order to improve the durability of the brake disc and the brake lining, a structure that efficiently dissipates heat energy due to friction is necessary while considering the positional relationship between the bolt fastening hole and the friction member of the brake lining.
JP-A-2005-321091

  The problem to be solved by the present invention is that in the conventional disc brake, the pressing force from the brake caliper acts only on a part of the brake lining, so that the contact surface pressure between the brake lining and the brake disc is just below the pressing force. And the temperature rise during brake operation may become excessive.

The brake lining for railway vehicles of the present invention is
A railcar brake lining that has a fastening hole in the sliding surface and is pressed by a brake caliper on the sliding surface of the disc body attached to the axle or the rail vehicle brake disc that is bolted to the wheel at the fastening hole. There,
A friction member pressed against the sliding surface of the brake disc;
A back plate attached to the brake caliper and supporting the friction member;
The friction member is
It is divided into two or more pieces in the radial direction of the brake disc,
Each of the divided friction members is arranged so as to avoid a concentric circle passing through the center of the fastening hole, and the center line in the radial direction of each of the friction members and the outline of the fastening hole are The most important feature is that the friction member is formed so as not to intersect during the brake operation.

  In the brake lining for a railway vehicle according to the present invention, the friction material of the brake lining is disposed so as to avoid the fastening hole, so that the heat energy generated by the friction during the brake operation can be transferred to the inner periphery of the brake disc across the fastening hole. It can be evenly distributed on the side and the outer peripheral side.

  In the brake lining for a railway vehicle of the present invention, when the friction member is divided and arranged in two or more in the circumferential direction of the brake disc, it is further effective that the contact surface pressure of the friction member is locally increased. Can be avoided.

  In the railway vehicle brake lining of the present invention, the shortest distance D between the center line and the outer shape line of the fastening hole is 10 mm or more, and the center position of the pressing load acting from the center line and the brake caliper If the distance on the inner peripheral side is Ri and the distance on the outer peripheral side is Ro, then if Ri / Ro is in the range of 0.8 to 2.2, The pressing load is well distributed on the outer peripheral side, and the thermal energy due to friction is more evenly distributed.

The disc brake for railway vehicles of the present invention is
A brake disc that is provided with a fastening hole on the sliding surface and is bolted to a disc body or a wheel attached to the axle at the fastening hole portion;
The most important feature is that the brake lining for a railway vehicle of the present invention attached to a brake caliper is provided.

  In the disk brake for railway vehicles of the present invention, the heat energy generated by friction during brake operation can be evenly distributed, so that the durability of both the brake disk and the brake lining can be greatly improved.

  According to the present invention, thermal energy generated by friction during brake operation is evenly distributed and the maximum temperature of the brake disc is reduced, so that thermal deformation and cracking of the brake disc can be reduced.

  Furthermore, since the contact surface pressure between the brake lining and the brake disc is reduced, wear of the brake lining and the brake disc can be reduced.

  Thereby, the durability of the brake lining and the brake disc is improved, and it is possible to cope with the increase in speed and size of the railway vehicle.

The best mode for carrying out the present invention will be described below with reference to FIG.
1A and 1B are views showing an embodiment of a brake lining according to the present invention. FIG. 1A is a plan view of the brake lining as viewed from the friction member side, and FIG. 1B is a cross-sectional view taken along line AB in FIG.

  In the case of a brake disc 2 that is bolted at a sliding portion as shown in FIG. 1 and is the subject of the present invention, the thermal energy due to friction during brake operation is effectively dispersed by paying attention to the following three points. can do.

(1) When the brake disc 2 and the brake lining 5 come into contact with each other in the vicinity of the fastening hole 2b provided in the sliding surface 2a, the contact surface pressure locally increases at that portion, and the thermal energy due to friction becomes excessive. Since the fastening hole 2b provided in the sliding surface 2a is substantially in the center position in the radial direction, the friction member 5a is disposed on the brake lining 5 so as to avoid the fastening hole 2b. It is important to disperse to the outer peripheral side.

(2) When the friction member 5a is dispersed on the inner and outer peripheral sides of the sliding surface 2a, the thermal energy per unit area absorbed by the brake disk 2 among the heat energy generated by friction is distributed on the inner and outer periphery. It needs to be even. By doing so, local temperature rise is suppressed, thermal deformation of the brake disc 2 is reduced, and wear of the brake lining 5 is also reduced. In order to achieve uniform thermal energy, the pressing position loaded from the brake caliper to the brake lining 5 is very important.

(3) Although the brake disc 2 is thermally deformed during the brake operation, in order to reduce the contact surface pressure even in such a state, it is effective to allow the friction member 5a to move following the deformation of the brake disc 2. large. For this purpose, the friction member 5a may be divided into a plurality of parts and each may be provided with a mechanism that moves independently.

The brake lining for a railway vehicle of the present invention is made based on the above concept.
That is, in the present invention, the friction members 5a have the following arrangement, size, and number.

  Since the contact surface pressure of the friction member 5a tends to increase at the central portion thereof, it is most important that the central portion of the friction member 5a does not interfere with the fastening hole 2b of the brake disk 2. Assuming that the friction member 5a is in uniform contact with the entire sliding surface 2a of the brake disk 2, the concentric circle passing through the center of the fastening hole 2b is locally at the position where the contact surface pressure is highest. It is important that the friction member 5a does not exist on a concentric circle passing through the center of the fastening hole 2b. Furthermore, when the friction member 5a slides on a concentric circle passing through the center of the fastening hole 2b, the side surface of the fastening hole 2b may come into contact with the friction member 5a. At that time, a great load is applied to the friction member 5a, and it is difficult to ensure durability.

  Therefore, in the present invention, in order to avoid locally increasing contact surface pressure, the friction member 5a is arranged so as to avoid a concentric circle passing through the center of the fastening hole 2b. The shortest distance D between the center line 7 and the outline of the fastening hole 2b of the brake disk 2 is set to be greater than 0 mm.

  In order to obtain a greater effect, the shortest distance D is preferably 10 mm or more. As described above, the contact surface pressure of the friction member 5a tends to increase at the center, but if the shortest distance D is set to 10 mm or more, the contact surface pressure is surely independent of the size of the friction member 5a. Interference between the region where the width of the fastening hole 2 and the fastening hole 2b are reduced. Although the upper limit of the shortest distance D depends on the size of the brake disc 2, it is preferable that the radial center line 7 of the friction member 5 a is at least 10 mm inside the inner and outer peripheral ends of the brake disc 2.

  Further, if the friction member 5a is too small, a sufficient contact area with the brake disk 2 cannot be secured. Therefore, the radial length L1 of the friction member 5a is preferably 20 mm or more. However, if the friction member 5a is too large, there is a possibility that it will interfere with the fastening hole 2b of the brake disc 2. Therefore, the radial length L1 is 0. 0 of the radial length L2 of the sliding surface 2a of the brake disc 2. It is preferable to make it 45 times or less.

  Further, two or more friction members 5a need to be arranged in the radial direction across the fastening hole 2b of the brake disk 2, but in order to avoid a local increase in the contact surface pressure of the friction member 5a, the circumferential direction of the friction member 5a is not limited. It is preferable to arrange a plurality of them in the direction.

  In FIG. 1, the number of divisions of the friction member 5a in the radial direction is 2, the number of divisions in the circumferential direction is 5 on the inner circumferential side, and 7 on the outer circumferential side. The circumferential length of one of the friction members 5a is preferably substantially equal to the radial length L1.

  In order for the friction member 5a to move following the deformation of the brake disk 2, it is preferable to insert the connection component 8 between the friction member 5a and the back plate 5b. As the connection component 8, a ring-shaped member, a ball-shaped member, and various springs (a disc spring or a radially arched leaf spring) can be applied.

  In FIG. 1, a connection spring 8 using a disc spring is shown. However, when such a spring is used, the spring constant is set to 6 to 12 kN / mm for the friction member 5a to move sufficiently. Is preferred.

  This is because when the spring constant is smaller than 6 kN / mm, the durability of the spring cannot be sufficiently secured, and when it is larger than 12 kN / mm, the friction member 5a cannot sufficiently move. More preferably, the spring constant is 8 to 10 kN / mm.

  The distance between the center position 6 of the pressing load acting on the brake lining 5 on which the friction member 5a is installed from the brake caliper and the radial center line 7 of the friction member 5a is defined as Ri on the inner peripheral side and Ro on the outer peripheral side. Then, Ri / Ro is preferably 0.8 to 2.2.

  By setting it as such a range, a pressing load is well disperse | distributed by the inner peripheral side and an outer peripheral side, and the heat energy by friction is disperse | distributed equally. More preferably, Ri / Ro is set to 1.2 to 1.8. Further, the center position 6 of the pressing load is preferably two or more in the circumferential direction, and is preferably positioned evenly on the same radius.

For the friction member 5a of the brake lining 5 of the present invention, generally used sintered materials and resin materials can be applied.
The brake caliper applied to the railway vehicle disc brake of the present invention having the brake disc 2 and the brake lining 5 of the present invention attached to the brake caliper can be applied to various systems such as a hydraulic type and a pneumatic type. It is.

  Hereinafter, the results of the finite element analysis for evaluating the thermal energy due to the friction between the brake disc and the brake lining during the brake operation will be described. The analyzed brake disc model is a type in which the bolt is fastened at the sliding portion, and a brake disc made of forged steel is assumed.

  In the finite element analysis, the brake lining and brake disc were modeled with elastic bodies, and a load equivalent to the pressing force from the brake caliper was applied from the back of the brake lining. In the finite element analysis, the arrangement of the friction member shown in FIG. 1, the pressing position loaded on the brake lining, and the structure of the portion where the friction member is attached to the back plate were changed. In addition, finite element analysis was also performed for a conventional brake lining.

Table 1 below summarizes the evaluated brake linings. Comparative Example 1 is a conventional brake lining.
Common to all brake linings, the brake lining for Shinkansen was targeted, and the longitudinal length of the brake lining was 400 mm and the length in the width direction was 130 mm. In addition, the material constituting the brake lining was a steel material for the back plate and a copper sintered alloy for the friction member.

  Brake conditions are equivalent to emergency braking from 360 km / h. The pressing force was 20 kN. The brake disc has an inner diameter of 439 mm and an outer diameter of 705 mm, and the fastening hole on the sliding surface has a diameter of 30 mm, and the center thereof is located on a circle having a diameter of 570 mm when viewed from the center of the brake disc.

  An object of the present invention is to improve durability of a brake disc and a brake lining. The average torque energy is obtained from the contact pressure distribution of the brake lining and brake disc obtained by finite element analysis, assuming that it is the average thermal energy per unit area due to friction, and the maximum temperature of the brake disc at that time Were also evaluated by finite element analysis.

  In addition, since the wear of the brake disc and the brake lining has a correlation with the contact surface pressure between them, the maximum contact surface pressure during brake operation was evaluated. The durability of the brake disc and brake lining improves as the maximum temperature of the brake disc is lower and the maximum contact surface pressure is lower.

  Table 2 below shows the maximum temperature and the maximum contact surface pressure of the brake disc. As can be seen from Table 2, the maximum temperature and the maximum contact surface pressure of each of the inventive examples are significantly lower than those of Comparative Example 1 which is a conventional brake lining.

  FIG. 2 shows the relationship between the maximum brake disc temperature and Ri / Ro for Examples 3 to 7 described above. From FIG. 2, it can be seen that the maximum temperature of the brake disc can be reduced when Ri / Ro is 0.8 to 2.2, particularly 1.2 to 1.8, and the maximum effect is 1.5.

  FIG. 2 shows the relationship when D is 25 mm. Invention Example 1 when D is 5 mm and Invention Example 2 when D is 15 mm are shown on the diagram shown in FIG. Needless to say, in these cases, the maximum temperature and the maximum contact surface pressure of the brake disk are significantly reduced as compared with Comparative Example 1. In particular, if D is 10 mm or more and Ri / Ro satisfies 0.8 to 2.2, the maximum brake disc temperature is preferably 750 ° C. or less.

  The present invention is not limited to the above-described example, and it goes without saying that the embodiments may be appropriately changed within the scope of the technical idea described in each claim.

  The present invention described above is not limited to a brake disk for a railway vehicle, but can be applied to a brake disk for an automobile, a motorcycle, or the like.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows one Embodiment of the brake lining of this invention, (a) is the top view which looked at the brake lining from the friction member side, (b) is AB sectional drawing of (a) figure. FIG. 2 is a diagram showing the relationship between the maximum brake disc temperature and Ri / Ro obtained by finite element analysis for the brake lining of the example of the present invention shown in FIG. 1. It is a schematic explanatory drawing of a side disk. It is a schematic explanatory drawing of an axis mount disc. It is the figure which showed the brake lining and brake disc which comprise the conventional disc brake for rail vehicles, (a) is the top view which looked at the brake lining from the friction member side, (b) is AB sectional drawing of (a) figure FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wheel 2 Brake disc 3 Axle 4 Disc body 5 Brake lining 5a Friction member 5b Back plate 6 Center position of pressing load 7 Center line of friction member in radial direction 8 Connection parts

Claims (4)

A railcar brake lining that has a fastening hole in the sliding surface and is pressed by a brake caliper on the sliding surface of the disc body attached to the axle or the rail vehicle brake disc that is bolted to the wheel at the fastening hole. There,
A friction member pressed against the sliding surface of the brake disc;
A back plate attached to the brake caliper and supporting the friction member;
The friction member is
It is divided into two or more pieces in the radial direction of the brake disc,
Each of the divided friction members is arranged so as to avoid a concentric circle passing through the center of the fastening hole, and the center line in the radial direction of each of the friction members and the outline of the fastening hole are The brake lining for a railway vehicle is characterized in that the friction member is formed so as not to intersect during a brake operation. The friction member is
The brake lining for a railway vehicle according to claim 1, wherein the brake lining is divided into two or more in the circumferential direction of the brake disc. The shortest distance D between the center line and the outline of the fastening hole is 10 mm or more;
Of the distance between the center line and the center position of the pressing load acting from the brake caliper, Ri / Ro is 0.8-2. Where Ri is the inner peripheral distance and Ro is the outer peripheral distance. The brake lining for a railway vehicle according to claim 1 or 2, wherein the brake lining is within a range of 2. A brake disc that is provided with a fastening hole on the sliding surface and is bolted to a disc body or a wheel attached to the axle at the fastening hole portion;
A disc brake for a railway vehicle, comprising the brake lining according to any one of claims 1 to 3 attached to a brake caliper.

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