JPH10129480A - Aluminum compound material rotor of disc brake for rolling stock - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent cracking or deformation from occurring around a bolt through hole through which an attaching bolt passes even if thermal expansion is generated by a temperature rise. SOLUTION: At the inner periphery part of a rotor body 23 integrally-formed of an aluminum compound material into a roughly disc shape, a fixing ring 25 made of iron material is fitted so that relative displacement can be made in the thickness direction of the rotor body 23 and may be regulated in the peripheral direction. A bolt through hole 21 which fastens it against the side surface of a wheel 8 by bolt 5 is formed at a fixing ring 25. The fixing ring 25 and the rotor body 23 under a fitted condition are pressed and fixed against the wheel 8 by the pressing force of a wavy leaf spring 28 fastened against the wheel 8 together with the fixing ring 25.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotor made of an aluminum-based composite material of a disk brake for a railway vehicle, which is formed into a substantially disk shape and fastened to a side surface of a wheel of a railway vehicle.

[0002]

2. Description of the Related Art Conventionally, as a disk brake for a railway vehicle, a substantially disc-shaped rotor is fastened to both inner and outer surfaces of a wheel of a railway vehicle by bolts, so that a sliding sliding surface for braking is provided on both sides of the wheel. Are known. In this type of conventional rotor, the rotor is manufactured from an iron-based material such as cast iron or forged steel. However, in recent years, railway vehicles have become more and more fast-moving, and accordingly, there has been a strong demand for weight reduction of parts constituting the vehicles. In particular, the weight of the wheels and the aforementioned rotors mounted on the wheels are unsprung masses that directly apply a load to the rails, which have a large effect on the vibrations and shocks applied to the rails and the running performance of the vehicle. Has been an important issue.

Therefore, in recent years, a rotor made of an aluminum-based composite material, which is a lightweight material, has been developed. The aluminum-based composite material referred to here is a composite material in which reinforced particles such as ceramic particles (Al ₂ O ₃ , SiO ₂ , SiC, etc.) are dispersed in a metal matrix of an aluminum alloy, and has a specific gravity of about 2.8. The weight can be reduced significantly as compared with conventional iron-based materials.

FIGS. 6 and 7 show the structure of a conventional rotor 1 made of such an aluminum-based composite material. The rotor 1 is integrally formed in a substantially disc shape with an aluminum-based composite material, and has a configuration in which a plurality of bolt through holes 3 are formed to penetrate near the inner periphery. As shown in FIG. 7, the vehicle is fastened to the side surface of the wheel 8 of the railway vehicle by the mounting bolt 5 and the nut 6 screwed to the mounting bolt 5.

[0005] The surface 9 of the rotor 1 is such that a certain range on the outer peripheral side becomes a sliding surface 9a for braking, and the range of the sliding surface 9a is finished flat. The back surface 10 of the rotor 1 is a surface that comes into contact with the side surface of the wheel 8 and has a structure in which cooling fins 10a protrude radially from the center of the rotor in order to enhance the heat radiation effect.

The bolt through hole 3 is a circular hole having an appropriate margin for the shaft diameter of the mounting bolt 5 and a nut 6.
The side is usually equipped with a spring washer 11 as a locking stop for the nut 6.

[0007]

However, during braking operation, the rotor 1 used in a high-speed vehicle heats up to about 250 to 300 ° C. due to frictional heat, and the resulting thermal expansion causes a problem as shown in FIG. The outer peripheral side is deformed into a substantially bowl shape protruding toward the front surface 9 side. An arrow (a) shown in FIG. 8 indicates a radial tensile stress (thermal stress) generated at the time of this substantially bowl-shaped deformation.

When the rotor 1 is thermally deformed in such a substantially bowl shape, as shown in FIG. 9, a bolt penetrates through the rotor 1 due to a tensile stress F acting due to radial thermal expansion. A part of the hole 3 (more precisely, the inner wall surface of the bolt through hole 3 on the rotor center side) is strongly pressed against the mounting bolt 5, and as a result, a concentrated load is applied to a part of the inner wall surface of the bolt through hole 3. Therefore, there is a problem that cracks and deformations are likely to occur in the periphery of the bolt through hole 3 due to the compressive load acting as follows.

Therefore, conventionally, as a means for preventing the occurrence of such a problem, as shown in FIG. 10, the diameter of the bolt through hole 3 is set to be larger beforehand, and the mounting bolt 5 and the bolt through hole 3 are set. It has been studied to increase the gap S between the inner wall surface of the rotor 3 and the disk spring 13 between the nut 6 and the rotor 1. However, the radial thermal expansion of the rotor 1 is considerably large. Therefore, these means have not yet achieved sufficient results.

In Japanese Utility Model Publication No. 8-5400, the amount of heat transferred from the rotor 1 to the wheels 8 is increased by increasing the contact area between the back surface 10 of the rotor 1 and the wheels 8.
A technique has been shown to suppress the occurrence of cracks and deformation at the periphery of the bolt through-hole 3 by suppressing the temperature rise itself of the bolt 1. It is extremely difficult to greatly reduce it, and it is still impossible to obtain sufficient results.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, and an object of the present invention is to provide a rotor made of an aluminum-based composite material for a disk brake for a railway vehicle, which is fastened to wheels by mounting bolts. However, there is no crack or deformation on the periphery of the bolt through-hole, and a rotor made of aluminum-based composite material for disc brakes for railway vehicles that can withstand the severe braking conditions of high-speed railway vehicles for a long period of time. To provide.

[0012]

According to the present invention, there is provided a rotor made of an aluminum-based composite material for a disk brake for a railway vehicle according to the present invention, which has a through hole in the center and is integrally formed in a substantially disk shape. A fixing member made of an iron-based material having a rotor main body and a through-hole for mounting bolts to the wheel, which is fitted and inserted into the central through-hole with a degree of freedom only in the thickness direction of the rotor with respect to the rotor main body. A ring, a corrugated leaf spring in which a pressing plate portion to be brought into contact with the rotor main body and a fastening plate portion having a through hole corresponding to a through hole for a fixing bolt of the fixing ring are connected in a stepwise manner; A configuration in which the pressing plate portion presses and fixes the rotor body and the fixing ring to the side surface of the wheel by tightening the fastening plate portion of the corrugated plate spring with the mounting bolt that penetrates the corrugated plate spring and the fixing ring. A.

Further, in order to achieve the above object, in the rotor made of an aluminum-based composite material for a railway vehicle disc brake according to the present invention, the fitting shape between the center through hole of the rotor body and the fixing ring is a gear. And the fixing ring has a through-hole for a mounting bolt provided on a protruding tooth portion of the fixing ring.

One of the causes of the cracks or deformation of the periphery of the bolt through hole of the rotor due to the thermal expansion due to the temperature increase is that the displacement of the periphery of the bolt through hole to the outer peripheral side of the rotor due to the thermal expansion is forcible. You may be restrained. More specifically, when the rotor is thermally expanded in the radial direction, the inner wall surface of a part of the bolt through-hole on the rotor center side is restricted by the displacement of the mounting bolt, so that the inner wall cannot fully respond to the thermal expansion.

Prior to that, for example, in the case of a mounting structure in which the rotor is directly tightened and fixed by a spring washer as shown in FIG. 9, the rotor changes over time in the mounting state due to thermal expansion in the thickness direction of the rotor. A depression occurs in the portion of the surface where the spring washer is in contact, and the entire range of the semicircle on the rotor shaft center side of the depression becomes a hook that regulates displacement due to thermal expansion of the rotor in the radial direction. Constraining radial displacement is also a significant factor that cannot be overlooked. The stress generated during thermal expansion in the radial direction due to the catch of the recessed portion rapidly increases at the peripheral portion of the bolt through hole on the rotor center side, and acts as a concentrated load on the peripheral portion of the bolt through hole on the rotor center side. Because it will.

On the other hand, in the configuration of the present invention described above,
On the inner periphery of the through hole of the rotor body made of an aluminum-based composite material that provides a sliding surface for braking, a separate fixing ring made of an iron-based material is fitted and fitted. A bolt insertion hole for screwing to a wheel of a railway vehicle is provided in the fixing ring. A part of each of the rotor body and the fixing ring in which the fixing ring is inserted into the inner peripheral part is covered with a corrugated leaf spring. First, the fastening plate part of the corrugated leaf spring is moved in the direction of the fixing ring by mounting bolts. Pressed. At the same time, the pressing plate portion of the corrugated leaf spring presses and fixes the rotor body to the wheel side surface. In other words, since the back surface of the wheel has the same configuration, the opposed fastening plate portions of the corrugated leaf springs disposed on the front and back of the wheel are tightened by the mounting bolts, so that the rotor body disposed on the front and back of the wheel is mounted. Can be pressed and fixed to the wheel side surface.

In this manner, the rotor body having no mounting hole does not cause unbalanced thermal expansion in the rotor body which is heated to a high temperature due to friction of the sliding surface during braking, and the expansion direction is restricted by the mounting bolt. It will not be done. Here, the force applied to the rotor during braking includes an axial force near the mounting bolt and a compressive stress that presses the rotor body against the wheel side surface. As in the present invention,
The fixing ring is provided with a through hole for a mounting bolt, and the configuration in which the degree of freedom is allowed only in the thickness direction of the rotor. The role of receiving the axial force is distributed to the fixing ring, while the compressive stress is transmitted from the pressing plate portion to the rotor body, so that the portion receiving the force is dispersed, and the durability can be further increased.

Further, since the fixing ring is made of an iron-based material having high mechanical strength and a small coefficient of thermal expansion as compared with the aluminum-based composite material, the stress acting due to the thermal expansion accompanying the temperature rise during braking is obtained. High durability against Therefore, even when a large thermal expansion occurs in the rotor body due to a temperature rise during braking or the like, the displacement due to the thermal expansion of the rotor body becomes a relative displacement between the rotor body and the fixing ring, and cracks or deformations occur at the periphery of the bolt insertion hole. And can withstand the severe braking conditions of high-speed railway vehicles for a long period of time.

Further, as described in claim 2, the fitting shape of the central through hole of the rotor main body and the fixing ring is a meshing shape of the gear, and is protruded radially from the inner periphery of the rotor main body. In the configuration in which the fixed ring is fitted to the inner periphery of the rotor body by engaging the engaged locking teeth with the teeth protruding from the outer periphery of the fixed ring, the rotor body faces the outer periphery with respect to the fixed ring. At the same time as displacement against radial thermal expansion is allowed, displacement against thermal expansion in the plate thickness direction is also allowed, and the rotor body has an ideal mounting state that does not exert excessive restraining force during thermal expansion. can get.

Further, the corrugated leaf spring includes a fastening plate portion which can be fastened to the side surface of the wheel of the railway vehicle together with the tooth portion of the fixing ring,
The pressing plate portion to be brought into contact with the locking teeth of the rotor body located between the tooth portions is stepped with each other, and alternately in a ring shape corresponding to the arrangement of the tooth portions and the locking teeth. Because of the continuous configuration, only one corrugated leaf spring is required to fix the rotor body, which suppresses the increase in the number of parts, and makes it clear at a glance that the wrong state of the front and back will not result in a fixed state. Can be eliminated on the mounting side, and assemblability can be improved.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiments. FIGS. 1 to 5 show an embodiment of an aluminum-based composite rotor for a railway vehicle disc brake according to the present invention. FIG. 1 shows an aluminum-based railway vehicle disc brake according to an embodiment of the present invention. FIG. 2 is a perspective view of a main part of the composite rotor, FIG. 2 is a perspective view of a fixing ring constituting one embodiment of the present invention, and FIG. FIG. 4 is a perspective view of a corrugated leaf spring constituting an aluminum-based composite rotor according to an embodiment of the present invention, and FIG.
It is sectional drawing which follows a line.

The aluminum-based composite material rotor 20 of this embodiment is used for a disk brake of a railway car running at high speed, and as shown in FIG. A rotor body 23 formed so that the surface 22 is a sliding surface 22a for braking;
3 is provided with a degree of freedom of relative displacement only in the thickness direction, and is fitted into a central through hole 29 in the inner peripheral portion of the rotor main body 23, and is fastened to a side surface of a wheel 8 of a railway vehicle by a mounting bolt 5. Fixing ring 25 made of iron-based material
A corrugated leaf spring 28 in which a pressing plate 26 to be brought into contact with the rotor main body 23 and a fastening plate 27 fastened to the wheel 8 together with the fixing ring 25 by the mounting bolt 5 are connected in a stepwise manner. The rotor body 23 fitted to the fixing ring 25 is pressed by the corrugated leaf spring 28 fastened to the wheel 8 together with the fixing ring 25 by the mounting bolts 5 and nuts 6. It is pressed and fixed to the side surface of the wheel 8.

As shown in FIG. 1, the rotor body 23 has locking teeth 23a protruding toward the center of the disk on its inner periphery.
Are protruded at regular intervals in the circumferential direction. The surface 22 of the rotor 20 has a certain area on the outer peripheral side serving as a sliding surface 22a for braking, and the area of the sliding surface 22a is finished flat. Also, the back surface of the rotor 20
Although not shown, in order to enhance the heat radiation effect on the surface which is in contact with the side surface of the wheel 8, a cooling fin is provided so as to project radially from the center of the rotor. The rotor body 2
The aluminum-based composite material that forms No. 3 is a composite material in which reinforcing particles such as ceramic particles are dispersed in a metal matrix of an aluminum alloy. Specifically, a material component such as Al ₂ O ₃ , SiO ₂ , or SiC is used. Sub-materials are uniformly mixed at a predetermined ratio, and the specific gravity is set to about 2.8.

As shown in FIG. 2, the fixing ring 25 has a ring portion 2 which can be inserted through the inner periphery of the rotor main body 23.
5a and the ring portion 2 so as to mesh with the locking teeth 23a.
A plurality of teeth 25b protruding from the outer periphery of 5a are integrally formed with an iron-based material such as cast iron or forged steel.
A bolt through hole 21 through which the mounting bolt 5 can be inserted is formed in the tooth portion 25b so as to penetrate the rotor body 23 along the thickness direction of the rotor body 23. As shown in FIG. 3, the rotor main body 23 and the fixing ring 25 are engaged with each other by locking teeth 23a and teeth 25b.

As shown in FIG. 4, the corrugated leaf spring 28 has a bolt insertion hole 27a through which the mounting bolt 5 can be inserted. The fastening plate 27 that can be fastened to the side surface of the wheel 8 of the vehicle and the pressing plate 26 that is in contact with the locking teeth 23a of the rotor body 23 located between the teeth 25b are stepped from each other. In addition, a configuration is provided in which the teeth 25b and the locking teeth 23a are alternately connected in a ring shape in accordance with the arrangement of the teeth 23a.

In the aluminum-based composite rotor 20 according to the embodiment of the present invention, the inner periphery of the aluminum-based composite rotor body 23 that provides the sliding surface 22a for braking is formed of an iron-based material. The formed separate fixing ring 25 is fitted and fitted, and the fixing ring 25 is provided with a bolt through hole 21 for screwing to the wheel 8 of the railway vehicle. Then, the fixing ring 2 is inserted into the central through hole 29 in the inner peripheral portion.
The rotor body 23 fitted with 5 is corrugated by a corrugated leaf spring 28 screwed to the wheel 8 together with the fixing ring 25.
It is pressed and fixed to the side surface of the wheel 8. Accordingly, the displacement of the rotor body 23, which rises to a high temperature due to the friction of the sliding surface 22a at the time of braking, due to the thermal expansion due to the temperature rise is not restrained by the mounting bolt 5. The displacement caused by the thermal expansion of the rotor body 23 can be tolerated in the radial direction and in the plate thickness direction by devising a fitting structure with the fixing ring 25.

Further, according to the present invention, as shown in FIG.
Is provided with through holes 21 for mounting bolts, and the fixing ring 25 has a degree of freedom only in the thickness direction of the rotor main body 23. By the action, the function of receiving the axial force is
It is distributed to. On the other hand, since the compressive stress is transmitted from the pressing plate portion 26 to the locking teeth 23a of the rotor body 23, the portions that receive the force are dispersed, and the durability can be further increased.

The fixing ring 25 whose displacement is restrained by the tightening of the mounting bolts 5 is made of an iron-based material having a higher mechanical strength and a smaller coefficient of thermal expansion as compared with the aluminum-based composite material. High durability against stress caused by thermal expansion accompanying temperature rise at the time. Therefore,
Even when a large thermal expansion occurs in the rotor main body 23 due to a temperature rise during braking or the like, the displacement due to the thermal expansion of the rotor main body 23 can be allowed as a relative displacement between the rotor main body 23 and the fixing ring 25, and the bolt through hole No cracks or deformations occur on the periphery of 21, and it is possible to withstand severe braking conditions in high-speed railway vehicles for a long period of time.

Further, in the rotor 20 of the present embodiment, the locking teeth 23a protruding radially from the inner periphery of the rotor body 23.
The fixed ring 25 is fitted to the inner periphery of the rotor main body 23 by meshing with the teeth 25 b projecting from the outer periphery of the fixed ring 25. Is allowed in the radial direction, and at the same time, the displacement in the plate thickness direction is also allowed. The mounting condition has been obtained.

The corrugated leaf spring 28 is attached to the fixed ring 2.
5, a fastening plate portion 27 that can be fastened to the side surface of the wheel 8 of the railway vehicle together with the tooth portion 25b, and a pressing plate portion that comes into contact with the locking teeth 23a of the rotor body 23 located between the tooth portions 25b. 26 are arranged stepwise and alternately in a ring shape corresponding to the arrangement of the teeth 25b and the locking teeth 23a, so that a corrugated leaf spring 28 necessary for fixing the rotor body 23 is provided. Only a single component is required, and an increase in the number of parts can be suppressed, and assemblability can be improved.

The locking teeth 23a provided on the inner periphery of the rotor body 23 and the teeth 2 provided on the outer periphery of the fixed ring 25 are provided.
The number of teeth, the tooth shape, and the size of 5b are not limited to those of the embodiment. The number of teeth, tooth shape, size, and the like can be appropriately changed in design.

[0032]

According to the rotor made of an aluminum-based composite material of a disk brake for a railway vehicle of the present invention, the rotor body which rises to a high temperature due to friction of the sliding surface during braking has a displacement accompanying thermal expansion due to the temperature rise. In addition, the configuration in which the fixing ring is provided eliminates direct restraint by the mounting bolt. The displacement caused by the thermal expansion of the rotor body can be tolerated in both the radial direction and the plate thickness direction by the fitting structure with the fixing ring. In addition, the fixing ring, whose displacement is restricted by tightening with mounting bolts, is made of an iron-based material that has higher mechanical strength and a smaller coefficient of thermal expansion compared to aluminum-based composite materials, so it can be used to raise the temperature during braking. High durability against the stress caused by the accompanying thermal expansion. Therefore, even when a large thermal expansion occurs in the rotor body due to a temperature rise during braking or the like, it can be allowed as a relative displacement between the rotor body and the fixing ring, and can be used for a long time even under severe braking conditions in a high-speed railway vehicle. It becomes possible to endure. The corrugated leaf spring includes a fastening plate portion that can be fastened to the side surface of the wheel of the railway vehicle together with the tooth portion of the fixing ring, and a pressing plate that abuts against a locking tooth of the rotor body located between the tooth portions. If the plate portions are arranged in a stepwise manner and alternately arranged in a ring shape corresponding to the arrangement of the tooth portions and the locking teeth, a single corrugated leaf spring required for fixing the rotor body is provided. Thus, an increase in the number of parts can be suppressed, and assemblability can be improved.

[Brief description of the drawings]

FIG. 1 is a perspective view of an aluminum-based composite rotor according to an embodiment of the present invention.

FIG. 2 is a perspective view of a fixing ring used in the aluminum-based composite rotor according to the embodiment of the present invention.

FIG. 3 is a perspective view showing a configuration of an aluminum-based composite rotor and a fixing ring according to the embodiment of the present invention.

FIG. 4 is a perspective view of a corrugated leaf spring used in the aluminum-based composite rotor according to the embodiment of the present invention.

FIG. 5 is a sectional view taken along the line AA in FIG. 3;

FIG. 6 is a perspective view of a rotor made of an aluminum-based composite material of a conventional disk brake for a railway vehicle.

FIG. 7 is a cross-sectional view of a state in which a conventional aluminum-based composite rotor of a disc brake for a railway vehicle is mounted on wheels.

FIG. 8 is a perspective view showing deformation of a rotor made of an aluminum-based composite material of a disc brake for a railway vehicle due to thermal expansion.

FIG. 9 is a cross-sectional view showing a problem that occurs during thermal expansion in an aluminum-based composite rotor of a conventional disk brake for a railway vehicle.

FIG. 10 is a sectional view showing a conventional countermeasure.

[Explanation of symbols]

 Reference Signs List 5 mounting bolt 6 nut 8 wheel 20 aluminum-based composite material rotor 21 bolt through hole 22 surface 23 rotor body 23a locking tooth 25 fixing ring 25a ring portion 25b tooth portion 26 pressing plate portion 27 fastening plate portion 28 corrugated leaf spring

Claims (2)

[Claims] An aluminum-based composite rotor for a railway vehicle disc brake fastened to a side surface of a railway vehicle wheel (2).
0), wherein a rotor body (23) having a through hole (29) at the center and integrally formed in a substantially disc shape, and being free with respect to the rotor body (23) only in a thickness direction of the rotor. A fixing ring (25) made of an iron-based material, which is fitted and inserted into the center through hole (29) with a certain degree, and has a through hole (21) for a mounting bolt to the wheel, and the rotor body (23). Pressing plate part (2
6) a corrugated leaf spring (28) in which a fastening plate portion (27) having a through hole (27a) corresponding to the through hole (21) for a mounting bolt of the fixing ring (25) is connected in a stepwise manner.
By pressing the fastening plate portion (27) of the corrugated leaf spring (28) with a mounting bolt (6) penetrating the corrugated leaf spring (28) and the fixing ring (25), the pressing is performed. A rotor made of an aluminum-based composite material for a railway vehicle disc brake, wherein a plate portion (26) presses and fixes the rotor body (23) and the fixing ring (25) to the side surface of the wheel. 2. The fitting shape of the central through hole (29) of the rotor body (23) and the fixing ring (25) is a meshing shape of a gear, and teeth of the fixing ring projecting therefrom. Through holes (21) for mounting bolts in the part (25b)
The rotor made of an aluminum-based composite material of a disk brake for a railway vehicle according to claim 1, wherein a rotor is provided.