JP4785516B2 - Railway vehicle brake linings and disc brakes - Google Patents

Description

  The present invention relates to a brake lining for a railway vehicle and a disk brake capable of reducing the contact surface pressure between the brake lining and the brake disk and improving the durability of the disk brake mainly for a railway vehicle.

2. Description of the Related Art In land transportation 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 braking force by friction between a brake disc and a brake lining, and presses the brake lining against the sliding surface of the brake disc attached to the axle or wheel to brake the rotation of the axle or wheel. Control the speed of the vehicle.

  During braking, the temperature at the contact surface between the brake lining and the brake disc rises due to frictional heat. However, the higher the speed or the greater the vehicle weight, the greater the brake load and the higher the contact surface temperature. There is a tendency.

  FIG. 7 shows a brake lining and a brake disc in a conventional disc brake for a railway vehicle. FIG. 7A is a plan view of the brake lining viewed from the friction member side, and FIG. 7B is a cross-sectional view taken along the line AB of FIG.

  The brake lining 1 is attached to a brake caliper (not shown), and a friction member 3 that comes into contact with the brake disk 11 is attached to the back plate 2 by a rivet (not shown).

The brake caliper is a device for obtaining a braking force by pressing the brake lining 1 against the brake disc 11, and there are a hydraulic type and a pneumatic type.
The pressing force applied to the brake lining 1 from the brake caliper does not act on the entire brake lining 1 due to the structure of the mounting portion, but acts on a specific portion. For example, in the case of a hydraulic caliper, there are two pressing load positions 21 as shown in FIG. Further, even in the case of a pneumatic caliper, the pressing force is loaded at substantially the same position.

  As described above, in the conventional disc brake, the pressing force from the brake caliper acts only on a part of the brake lining 1 due to its structure. For this reason, in the contact surface of the brake lining 1 and the brake disc 11, the difference between the portion where the contact surface pressure is high and the portion where the contact surface pressure is low is large. For example, the contact surface pressure between the brake lining 1 and the brake disc 11 tends to increase immediately below the pressing load position 21 where the pressing force from the brake caliper acts.

  In the portion where the contact surface pressure is high, more energy required for deceleration is input, and therefore, particularly in a high-speed vehicle such as a Shinkansen, the temperature rise during braking may be excessive. Further, when the contact surface pressure increases and the temperature rises, the amount of wear of the brake lining 1 and the brake disc 11 increases, which may cause cracks in the brake disc 11 and the like. Therefore, in order to ensure the durability of the brake lining 1 and the brake disc 11, it is important to reduce the contact surface pressure between them during braking.

  In particular, in a high-speed vehicle represented by the Shinkansen, the brake disk 11 is deformed due to a temperature rise during braking, so that the contact pressure between the brake lining 1 and the brake disk 11 tends to be higher.

FIG. 8 is a radial-axial sectional view schematically showing the contact state between the brake disc and the brake lining during braking in the Shinkansen brake disc.
When a braking force is applied from the high speed state, the temperature in the vicinity of the sliding surface 11a of the brake disk 11 rises, and the brake disk 11 is deformed into a convex shape as shown in FIG. When the brake disc 11 is deformed in this way, the brake lining 1 and the brake disc 11 come into contact only in the vicinity of the convex apex, the contact area is reduced, and the contact surface pressure is locally increased.

Therefore, as shown in FIG. 9, the friction member 3 is divided into a plurality of parts, and a structure in which the pressing force from the brake caliper is equally applied to each friction member 3, A technique for reducing the contact surface pressure of a brake disk is disclosed in Patent Document 1. In addition, 22 in FIG. 9 shows the radial center position of the brake disk sliding surface.
JP 10-507250 gazette

  However, although the technical idea disclosed in Patent Document 1 is divided into a plurality of friction members, the arrangement positions of the divided friction members are taken into account until the brake disk is deformed by a brake load. Absent. Therefore, as a matter of course, as shown in FIG. 9, the friction member is also arranged at the radial center position of the brake disk sliding surface.

  As shown in FIG. 9, when the friction member is arranged at the radial center position of the brake disk sliding surface, when the brake disk is deformed into a convex shape, the brake lining and the brake disk come into contact with each other at the convex vertex, There is a possibility that the contact surface pressure becomes high at that portion.

  The problem to be solved by the present invention is that when the contact surface pressure between the brake lining and the brake disc is reduced during braking to improve the durability of each of the brake linings and the brake disc, There has been no attempt to optimize the arrangement of the members and the pressing load position of the brake lining.

  If the pressing force from the brake caliper to the brake lining is distributed widely over the entire contact surface between the brake lining and the brake disc, especially in the radial direction of the brake disc, both contact surfaces even when the brake disc is deformed by braking from high speed Pressure can be reduced.

Based on this idea, the inventors have established the present invention as follows.
That is, the brake lining for railway vehicles of the present invention is
Even when the brake disc is deformed due to braking from high speed, the pressure applied to the brake lining is distributed over the entire contact surface between the brake lining and the brake disc, particularly in the radial direction of the brake disc to reduce the contact surface pressure between them. In addition,
A brake lining for a railway vehicle that is pressed against a sliding surface of a brake disc attached to both sides of a wheel or an axle by a brake caliper,
A friction member pressed against the sliding surface of the brake disc;
A back plate for supporting the friction member and attaching to the brake caliper is provided.
The friction member is divided into a radially inner peripheral side and an outer peripheral side at the center of the brake lining, which is a portion corresponding to the center position in the radial direction on the sliding surface of the brake disc, and also divided in the circumferential direction of the brake disc. And a groove in the circumferential direction of the brake disc at the center position in the radial direction,
Between each of the divided friction members and the back plate, the pressing force from the brake caliper is distributed and transmitted to the respective friction members in the radial direction of the brake disc with the back plate side as the top. The most important feature is that a plurality of pressing force distribution portions each having an arch shape are provided on each of the friction members divided on the radially inner and outer peripheral sides.

  In the brake lining for a railway vehicle according to the present invention, the friction member is divided into an inner peripheral side and an outer peripheral side in the radial direction at the center of the brake lining, which is a portion corresponding to the central position in the radial direction of the brake disk sliding surface. The friction member can follow the deformation of the brake disk.

  Here, dividing the friction member into the radially inner and outer circumferential sides means that at least a portion of the friction member in contact with the brake disk is divided into slits at the radial center portion (lining center). Let's say what is being. Therefore, it is used as a concept including both a completely divided portion and a portion that is divided only halfway. Needless to say, it is more preferable that the friction member is completely separated in terms of easy deformation. .

  Note that this division position may be slightly shifted. When the division positions are deviated, the deviation amounts are preferably within a range of 10 mm on the inner and outer circumferences in the radial direction.

  In addition, the brake lining for a railway vehicle according to the present invention further includes a pressing force distribution portion between the friction member and the back plate. Therefore, the pressing force from the brake caliper to the brake lining is distributed to each friction member. I can tell you.

  Due to the above synergistic effect, in the brake lining for a railway vehicle according to the present invention, it is possible to effectively suppress an increase in the contact surface pressure between the brake lining and the brake disc, and as a result, the durability of the brake lining and the brake disc. Will improve.

In the railcar brake lining according to the present invention, in order to secure a contact area between the brake lining and the brake disc , a plurality of the pressing force distribution portions are respectively provided on the friction members divided on the inner peripheral side and the outer peripheral side in the radial direction. It is provided one by one.

  In this case, the width in the circumferential direction of the brake disk of the pressing force dispersing portion is preferably substantially the same as the width of the friction member as a total value, but at least 1/2 or more of the width of the friction member. Is preferred.

  Although it is preferable that the plurality of pressing force distribution portions provided in a plurality are arranged uniformly, it is not necessary to have the same number on the inner peripheral side and the outer peripheral side of the brake disc. Further, it may not be completely uniform in the circumferential direction of the brake disc.

Further, the pressing force distribution unit, since the set to be arched the back plate side in the radial direction of the brake disc to the top, can in a distributed at four places the pressing force from the brake caliper in the radial direction, The effect of reducing the contact surface pressure is further increased.

  The pressing force dispersing portion described above may be formed integrally with the back plate or the friction member, or may be fixed by inserting another member between them. In the case of another member, for example, various members such as a ring-shaped member can be applied. However, if a member having a spring characteristic such as a disc spring is used, the friction member is more easily deformed and the effect is great.

  In the case where the pressing force dispersing portion is another member, it is usually attached to the friction member and the back plate with bolts, rivets or the like in the vicinity of the central portion thereof. However, for example, when the friction member is divided at the central portion of the pressing force distribution portion (when a plurality of friction members divided in the circumferential direction and one pressing force distribution portion are combined), etc., each is divided. What is necessary is just to fasten these friction members, pressing force dispersion | distribution parts, and a back plate with a volt | bolt, a rivet, etc.

Contact position between the back plate and the pressing force distribution unit, although in the so that further than 20mm from the brake lining center, and more preferably are separated by more than 30 mm. This is because if the contact position is too close to the center of the brake lining, the dispersion effect of the pressing force is reduced.

In addition, this contact position does not need to be the same on the radially inner and outer peripheral sides of the brake disc, but in order to distribute the pressing force evenly on the inner and outer peripheral sides, The difference in the contact position on the outer peripheral side should be small and is preferably within 10 mm.
The above pressing force dispersion portion preferably has a thickness of 2 mm or more in order to ensure sufficient strength.

  It is appropriate to use a steel material from the viewpoint of strength, rigidity, and workability for the above-mentioned pressing force dispersion part. However, if these performances are satisfied, a non-ferrous metal material or a non-metal material may be used. .

  Further, if the friction member is also divided in the circumferential direction of the brake disc, the contact surface pressure between the brake lining and the brake disc can be further reduced. However, since the structure becomes complicated if it is excessively divided, it is preferable to make it 8 or less.

  When the friction member is also divided in the circumferential direction of the brake disk as described above, each of the friction members divided in the circumferential direction may be provided with at least one pressing force distribution portion. preferable.

The disc brake for railway vehicles of the present invention is
Brake discs attached to both sides of the wheel or axle;
Comprising the brake lining of the present invention described above attached to a brake caliper;
A brake force is obtained by pressing the brake lining against the sliding surface of the brake disc by the brake caliper.

  Note that generally used sintered materials and resin materials can be applied to the friction member which is a component of the brake lining of the present invention. In addition, various types of brake calipers that are components of the disc brake of the present invention, such as a hydraulic type and a pneumatic type, can be applied.

  According to the present invention, it is possible to effectively reduce the contact surface pressure between the brake lining and the brake disc, and to reduce the occurrence of wear and cracks on the brake lining and the brake disc. As a result, the durability of the brake lining and the brake disc is improved, and the speed and size of the railway vehicle can be increased.

Hereinafter, various embodiments and best modes for carrying out the present invention will be described with reference to FIGS. 3 to 4 along with the progress from the idea to the solution of the problem.
The contact pressure between the brake lining and the brake disc increases locally during braking from high speed because the pressing force from the brake caliper concentrates on a specific part and the brake disc deforms into a convex shape due to temperature rise. This is because the contact area becomes smaller.

  If the pressing force can be dispersed especially in the radial direction of the brake disc as described above, the pressing force from the brake caliper does not concentrate on a specific part, and the brake disc is deformed and the contact area is increased. It becomes possible to avoid becoming smaller.

  The reason why the pressing force is distributed in the radial direction of the brake disc is that the vertex of the brake disc deformed into a convex shape during braking is substantially at the center position in the radial direction of the sliding surface. Therefore, if the pressing force is distributed to the inner peripheral side and the outer peripheral side of the center in the radial direction, it is possible to prevent the contact surface pressure from increasing at the center in the radial direction.

  Such a distribution of the pressing force seems to be possible, for example, by distributing the points at which the back plate is pressed by the brake caliper to the inner peripheral side and the outer peripheral side of the center in the radial direction, but the rigidity of the back plate is high. In addition, it is difficult to cause the friction member to follow the brake disk deformed into a convex shape only by dispersing the pressing points.

  Accordingly, the pressing force can be dispersed only by inserting a member that disperses and loads the pressing force between the back plate and the friction member. If such a member is inserted, the pressing force is transmitted from the radially inner and outer friction members to the convexly deformed brake disc, and as a result, the contact surface pressure between the brake lining and the brake disc. Can lead to improved durability of each.

  However, even if the member is inserted and the pressing force is dispersed, if the brake lining cannot be deformed following the deformation of the brake disk, it is difficult to ensure a sufficient contact area between the two. Therefore, in order to exhibit the effect of dispersing the pressing force, it is necessary to configure the friction member to follow the brake disc deformed into a convex shape. For that purpose, it is important to divide the friction member at the center position in the radial direction of the brake disk sliding surface to facilitate deformation.

The brake lining for a railway vehicle according to the present invention has been made based on the above idea and consideration. For example, as shown in FIG. 3, the inner peripheral side of the sliding surface 11a of the brake disk 11 at the radial center position 22 is provided. The friction members 3a and 3b are divided on the outer peripheral side. And, between these divided friction members 3a, 3b and the back plate 2, for example, the back plate 2 side is the top, and the pressing force distribution portion 4 that is arched only in the radial direction of the brake disk 11 is inserted, The pressing force acting on the friction members 3a and 3b is dispersed at four locations in the radial direction. Also, in the circumferential direction of the brake disc 11, the friction member 3a on the inner peripheral side is divided into four parts, the friction member 3b on the outer peripheral side is divided into five parts, and the brake disk is arranged at the radial center position of each friction member 3a, 3b. The grooves 5 are provided in the circumferential direction.

In the example of FIG. 2, the friction members 3a and 3b are not divided in the circumferential direction of the brake disk 11 in place of the friction members 3a and 3b of FIG. 3, and the radii of the friction members 3a and 3b are not divided. This is a comparative example in which no groove is provided in the circumferential direction of the brake disc at the center in the direction. Further , in the example of FIG. 1, instead of the pressing force dispersion portion 4 of FIG. 2, a ring-shaped pressing force dispersion portion 4 is inserted, and the pressing force acting on the friction members 3 a and 3 b is dispersed in two locations in the radial direction. This is a comparative example.

  Further, in the example of FIG. 4, instead of the pressing force dispersion portion 4 of FIG. 3, one pressing is performed by the adjacent friction members 3 a and 3 a, 3 b and 3 b except for the friction member 3 b located at the center on the outer peripheral side. A force distribution unit 4 is provided.

  Thus, when the groove 5 is provided in the circumferential direction of the brake disk at the radial center position of the friction members 3a and 3b, the friction members 3a and 3b are deformed in the radial direction of the sliding surface 11a of the brake disk 11. As a result, the effect of suppressing the contact surface pressure between the brake lining and the brake disc is further improved.

  At this time, in order to exert more effect, the depth of the groove 5 is preferably 0.5 times or more the plate thickness of the friction members 3a and 3b, and the strength of the friction members 3a and 3b is ensured. For this purpose, it is preferably 0.9 times or less.

  Needless to say, the effect of suppressing the contact surface pressure is further improved if the grooves 5 are completely divided at the radial center positions of the friction members 3a and 3b instead of providing the grooves 5.

  In the disc brake that obtains braking force by pressing the brake lining of the present invention against the sliding surface of the brake disc attached to the wheel or axle by the brake caliper, the contact surface pressure between the brake lining and the brake disc can be effectively reduced. It becomes possible to reduce the occurrence of wear and cracks in the brake lining and brake disc. This improves the durability of the brake lining and brake disc. This is the railway vehicle disc brake of the present invention.

To evaluate the brake lining (invention example) and the contact surface pressure of the brake disc of the present invention shown in FIG. 3 above, will be described results of finite element analysis. 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.

As a comparison, the conventional brake lining (conventional example 1) in which the pressing force shown in FIG. 7 is not dispersed and is applied to the friction member and the friction member shown in FIG. 9 are divided into 18 pieces, and each friction member is divided. The finite element analysis was also performed on the brake lining (conventional example 2) having a structure in which the pressing force is equally distributed. Further, Comparative Examples 1 to 5 of the brake lining of the present invention using the ring-shaped pressing force dispersion portion 4 shown in FIG. 1 and the friction members 3a and 3b shown in FIG. Is not divided, and the friction linings shown in FIG. 3 are compared with comparative examples 6 to 11 of the brake lining of the present invention in which the grooves are not provided in the circumferential direction of the brake disc at the radial center positions of the respective friction members 3a and 3b. member 3a, in 3b, the friction member 3a, in the radial direction central position of 3b, even with the comparative examples 12 to 13 of the brake lining of the present invention provided with no grooves in the brake disc circumferential direction was finite element analysis.

  The purpose of the present invention is to improve the durability of the brake lining and the brake disc, and it is considered that the durability of both increases as the contact surface pressure between the brake lining and the brake disc decreases. For the deformation state, the maximum contact surface pressure obtained by finite element analysis was evaluated.

Here, as shown in FIGS. 1 to 3, the position of the pressing force acting on the friction member 3 was determined based on the radial center position 22 of the brake disk sliding surface.
Point A represents an end point of the contact portion between the back plate 2 and the pressing force dispersion portion 4 on the side close to the radial center position 22 of the brake disk sliding surface. Point B represents the end of the contact portion between the pressing force distribution portion 4 and the friction members 3a and 3b on the side close to the radial center position 22 on the sliding surface of the brake disk when the pressing force distribution portion 4 is arched. The point represents the end of the contact portion between the pressing force distribution portion 4 and the friction members 3a and 3b on the far side.

  D1 represents the distance from the radial center position 22 of the brake disk sliding surface to the point A. d2 represents the brake disc radial distance between points A and B, and d3 represents the brake disc radial distance between points A and C, respectively.

  All were targeted for Shinkansen brake lining, and the length of the brake lining in the longitudinal direction was 400 mm and the length in the width direction was 130 mm. 1 has a thickness of 2 mm and an outer diameter of 20 mm. The outer friction member 3a has 10 pieces at equal intervals, and the inner friction member 3b. 8 were arranged at equal intervals. 2 and 3, the arch-shaped pressing force distribution part 4 has a thickness of 3 mm, an arch height of 1 mm, a radial length of the brake disc 11 of 45 mm, and a circumferential direction of the brake disc 11. The length arranged on the inner peripheral side was 45 mm, and the length arranged on the outer peripheral side was 65 mm. The outer friction member 3a is arranged at five equal intervals, and the inner friction member 3b is arranged at four equal intervals.

  The material constituting the brake lining was a steel material for the back plate and a copper sintered alloy for the friction member. The brake conditions were equivalent to emergency braking from 360km / h, and the target was the state where the pressing force was 20kN and the brake disc was most deformed. The brake disc is a forged steel brake disc, and the outer diameter of the sliding surface that comes into contact with the brake lining is 720 mm and the inner diameter is 465 mm.

  Table 1 below summarizes the brake linings evaluated. Table 2 below shows the maximum contact surface pressure obtained by finite element analysis for each brake lining.

From Table 2, the inventive examples, pressing and with force is dispersed radially, the friction member is divided in the sliding surface center of the brake disc, as compared with the conventional example 1 is a conventional brake lining It can be seen that the maximum contact surface pressure is significantly reduced. Further, it can be seen that the maximum contact surface pressure is low and the durability is improved as compared with the brake lining of Conventional Example 2.

FIG. 5 shows the relationship between the maximum contact surface pressure and d1 in Comparative Examples 1-5. From FIG. 5, it can be seen that the maximum contact surface pressure decreases as d1 increases, and that the effect increases more when d1 is 20 mm or more, but the maximum contact surface pressure does not change much when 30 mm or more.

FIG. 6 shows the relationship between the maximum contact surface pressure and d1 in Comparative Examples 6 to 11 using an arch-shaped pressing force dispersing portion. From FIG. 6, it can be seen that the maximum contact surface pressure is reduced as d1 is increased, and that the effect is increased when d1 is 20 mm or more, and the maximum contact surface pressure is reduced most at 35 mm.

Comparing FIG. 5 and FIG. 6, it can be seen that the maximum contact surface pressure is reduced in Comparative Examples 6 to 11 using the arch-shaped pressing force dispersion portion even in the same d 1 as compared with Comparative Examples 1 to 5. .
Further, compared to Comparative Example 9 , Comparative Examples 12 and 13 in which the friction member is also divided in the circumferential direction has a lower maximum contact surface pressure. Compared to Comparative Example 13 , the brake disk circumferential direction is located at the center of the friction member. It can be seen that the maximum contact surface pressure is further reduced in the example of the present invention in which the groove is provided.

The present invention is not limited to the above example, and it goes without saying that the embodiment may be appropriately changed within the scope of the technical idea described in each claim.
The shape of the pressing force dispersion portion is not limited to the shape shown in the above example, and the number of installations may be at least one provided on the inner peripheral side and the outer peripheral side from the radial center (lining center). . For example, the pressing force dispersion part may be formed to be substantially similar to the divided friction member and smaller than the friction member, or may be divided into a plurality of parts.

  In the above example, the pressing force distribution portion is fastened between the back plate and the friction member with bolts or rivets. However, the present invention is not limited to this, and the back plate or the friction member is previously integrated in a protruding shape. Alternatively, it may be previously connected to any means by any means.

  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.

(A) is the top view which looked at the brake lining of the 1st comparative example from the friction member side, (b) is AB sectional drawing of (a) figure. (A) is the top view which looked at the brake lining of the 2nd comparative example from the friction member side, (b) is AB sectional drawing of the (a) figure. (A) is the top view which looked at the 1st brake lining of this invention from the friction member side, (b) is AB sectional drawing of (a) figure. It is the top view which looked at the 2nd brake lining of the present invention from the friction member side. It is a figure which shows the relationship between the maximum contact surface pressure and d1 in Comparative Examples 1-5. It is a diagram showing the relationship between the maximum contact surface pressure and d1 in Comparative Examples 6-11. (A) is the top view which looked at the conventional type brake lining from the friction member side, (b) is AB sectional drawing of (a) figure. It is a radial direction-axial direction sectional view showing typically the contact state of the brake disc and brake lining under brake in the Shinkansen brake disc. It is the top view which looked at the brake lining which divided and arranged the friction member into the plurality from the friction member side.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Brake lining 2 Back plate 3 Friction member 4 Pushing force dispersion | distribution part 11 Brake disc 11a Sliding surface 22 Center position of radial direction of brake disc sliding surface

Claims (5)

A brake lining for a railway vehicle that is pressed against a sliding surface of a brake disc attached to both sides of a wheel or an axle by a brake caliper,
A friction member pressed against the sliding surface of the brake disc;
A back plate for supporting the friction member and attaching to the brake caliper is provided.
The friction member is divided into a radially inner peripheral side and an outer peripheral side at the center of the brake lining, which is a portion corresponding to the center position in the radial direction on the sliding surface of the brake disc, and also divided in the circumferential direction of the brake disc. And a groove in the circumferential direction of the brake disc at the center position in the radial direction,
Between each of the divided friction members and the back plate, the pressing force from the brake caliper is distributed and transmitted to the respective friction members in the radial direction of the brake disc with the back plate side as the top. A brake lining for a railway vehicle, wherein a plurality of pressing force dispersion portions each having an arch shape are provided on each of the friction members divided on the radially inner and outer peripheral sides.   2. The brake lining for a railway vehicle according to claim 1, wherein the pressing force dispersing portion is configured by inserting and fixing a member different from the back plate or the friction member therebetween.   The brake lining for a railway vehicle according to claim 1 or 2, wherein a distance between a contact position between the pressing force distribution portion and the back plate and a center of the brake lining is 20 mm or more.   The brake lining for a railway vehicle according to any one of claims 1 to 3, wherein each of the friction members divided in the circumferential direction is provided with at least one pressing force distribution portion. Brake discs attached to both sides of the wheel or axle;
The brake lining according to any one of claims 1 to 4 attached to a brake caliper,
A disc brake for a railway vehicle, wherein the brake lining is pressed against the sliding surface of the brake disc by the brake caliper to obtain a braking force.

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