JPH0820335A - Structure for independently rotating wheel and axle - Google Patents

Abstract

PURPOSE:To prevent a slip on treads of wheels on a curve road having a small radius of curvature by inserting the first axle into the second axle, providing radial bearings and thrust bearings between both axles, and providing brake disks on both axles. CONSTITUTION:The first axle 22 provided with the first wheel 21 is inserted into the second axle 24 having a hollow structure and provided with the second wheel 23. Thin radial bearings 25, 26 maintaining the axes of both axles 22, 24 and thrust bearings 27, 28 maintaining the axial positions of both axles 22, 24 are provided between the first and second axles 22, 24. The axles 22, 24 are provided with the first and second brake disks 30, 31 at positions adjacent to each other. Two brake disks 30, 31 can be concurrently braked by the action a brake device 7 constituted of a brake shoe 8, a brake lever 9, and a brake cylinder 10, and equal brake torque can be applied to the axles 22, 24.

Description

Detailed Description of the Invention

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of wheels and axles for a railroad vehicle, and in particular, a structure in which left and right wheels can rotate independently. .

2. Description of the Related Art Wheels and axles for railway vehicles that have been conventionally used are mainly one in which a pair of left and right wheels are firmly assembled and integrally rotated. In this case, the tread surface of the wheel has a slope, and the effective wheel diameter is determined at the position where the wheel contacts the rail. Therefore, when the wheel axle (assembly of wheels and axles) moves laterally, the diameter of one wheel changes and the other changes slightly.
Depending on the ratio of the diameters of the left and right wheels at this time, the wheels can roll on a curved road without slipping. This will be described with reference to FIGS. In FIG. 1, the solid line indicates that the wheel shaft is at the center of the track, the left wheel 1 and the right wheel 2 have the same diameter, and the value is D ₀ . The dotted line shows the state in which the wheel axle has moved laterally, and the diameter of the left wheel 1 is D due to the lateral movement d.
₁ , larger than D ₀ , the diameter of the right wheel 2 is D ₂ , D
_Less than ₀ . In this way, a diameter ratio is created between the left and right wheels. The relationship between the lateral movement d and the diameter ratio k ₁ is as follows. _{k 1 = D 1 / D 2} = (D 0 + 2di) / (D 0 -2d
i) where i is the slope of the tread. Next, when the vehicle travels on the curved road of FIG. _2, the diameter ratio k ₂ of the left and right wheels required to prevent the treads of the wheels from slipping is as follows. _{k 2 = L 1 / L 2} = A (R + g / 2) / A (R-g /
2) Alternatively, at the obtained wheel diameter ratio k, the curve radius R is the limit at which the vehicle can travel without slipping on the tread surface of the wheel.
Is as follows with k ₁ = k ₂ = k. R = g (k + 1) / 2 (k-1) The results are obtained using the following numerical values which are considered to be the maximum practically possible. D ₀ = 660 mm d = 15 mm i = 1/10 g = 1435 mm, and the result is k = k ₁ = (660 + 3) / (660-3) = 1.00.
91 R = 1435 (1.091 + 1) / 2 (1.009)
1-1) = 158410 mm = 158.4 m. As is clear from the above relationship, when the curve radius is less than 158.4 m, the vehicle runs with slippage on the treads of the wheels. When running with slip on the tread, the slip is not constant and tends to be intermittent, which causes vibration and noise, which makes the ride uncomfortable and causes abnormal wear of rails and wheels. . On the other hand, unless a large amount of brake energy is required for high-speed railways exceeding 100 km / h, the commuting vehicles and the like tend to have one brake disc per axis to simplify the structure. The case is shown in FIG.
The left wheel 1 and the right wheel 2 are rigidly assembled to the axle 3 and only one brake disc 6 is provided on it. A set of brake devices 7 including a brake shoe 8, a brake lever 9, and a brake cylinder 10 acts on the brake disc 6. Reference numeral 11 is a brake device support arm, and 12 is a lateral beam of the bogie frame. Reference numeral 13 is an axle bearing that supports the load of the vehicle, and 14 is an axle bearing seat. As a means for solving the problem caused by running with slippage on the tread, it has been proposed to provide a structure in which the left and right wheels can rotate independently. It has the structure of FIG. 4 disclosed in the magazine “Railway Pictorial 1993-3 special edition, page 23”. It has wheels 15 of the same structure on the left and right, and supports the weight of the vehicle through a wheel bearing 16 and an axle tube 17 that does not rotate. The left and right wheels can rotate independently. The wheel bearing is required to support the weight of the vehicle and withstand a high speed of rotation in accordance with the traveling speed. In addition to the independent rotating structure of the wheels, in this embodiment, the left and right wheels are connected through the torque shaft 18 and the powder coupling 19, and the powder coupling is not connected at low speed running, but at high speed running. A device is added to combine the wheels so that the left and right wheels rotate together. Even if the torque shaft and the powder coupling are not added, the structure of this independent rotation is complicated as a whole, the wheel bearing is large due to the required bearing capacity, and the brake disc 20 is provided for each wheel. Two of them are arranged in two places, and the braking device that acts on them is also two.
A pair is needed. Further, this wheel set is far from the generally used one shown in FIG. 3, and the trolley structure using the wheel set is quite special, which is disadvantageous because of many design restrictions.

The overall structure is simple,
The structure of an independently rotating wheel and axle that can be handled equivalent to one brake disc per axle and can be replaced by the fixed wheel and axle in a bogie with a conventional structure, eliminating slippage on the tread of the wheel even on curved roads with a small radius of curvature. Is provided.

In order to solve the above problems, a first wheel is provided on a first axle and a second wheel is provided on a second axle.
Is provided with a wheel, and the second axle has a hollow structure through which the first axle penetrates. Between the first axle and the second axle, there is a radial bearing that maintains the axial center of both axles and the axial position of both axles. Has a thrust bearing, which holds a first brake disc on the first axle and a second brake disc on the second axle,
By providing the brake disc and the second brake disc in the adjacent position.

The first axle is provided with the first wheel, the second axle is provided with the second wheel, and the second axle has a hollow structure through which the first axle penetrates. Since the radial bearings that maintain the shaft centers of both shafts are provided between the axles, the first axle and the second axle can rotate relative to each other. Therefore, the first wheel provided on the first axle and the second wheel provided on the second axle.
The wheels of the can rotate independently. Further, since it has a thrust bearing for keeping the axial positions of both shafts, the left-right space between the first wheel and the second wheel can be maintained. Further on the first axle the first
Has a second brake disc on the second axle, and the first brake disc and the second brake disc are provided in adjacent positions, so that a pair of both discs are sandwiched between them. By providing the brake device, the two brake discs can be handled as if they were one brake disc, and the same brake torque can be applied to both the first wheel and the second wheel.

Embodiments of the present invention will be described in detail with reference to the drawings. 5 is a plan view of an embodiment showing the entire wheel and axle of the present invention, and FIG. 6 is a partially enlarged view of FIG. The first wheel 21 is provided on the first axle 22, and the second wheel is provided on the second axle 24.
Wheel 23 is provided, the second axle has a hollow structure through which the first axle penetrates, and thin radial bearings 25 and 26 that maintain the axes of both axles are provided between the first axle and the second axle. It has thrust bearings 27 and 28 that maintain the axial positions of both shafts. The rotational speed of these bearings is only a slight difference between the left and right wheel rotations so that the treads of the wheels do not slip on curved roads. Therefore, the "product of load and rotational speed" that determines the size of the bearing is much smaller than in the case of Fig. 4 and the bearing can be made thinner, which allows the first axle in the second axle. The structure allows the axle to penetrate therethrough. The first axle has a first brake disc 30, the second axle has a second brake disc 31, and the first brake disc and the second brake disc are provided at positions adjacent to each other. By doing so, the external appearance is the same as that of the conventional case shown in FIG. 3, and the dimensions can be almost the same. Here, the two brake discs 30 and 31 can be handled as if they were one brake disc with only one set of the brake device 7 including the brake shoe 8, the brake lever 9, and the brake cylinder 10, and the first wheel It is possible to apply an equal braking torque to both the second wheel and the second wheel. Numeral 32 is a floating metal provided to prevent the brake disc from being bent due to the pressure of the brake shoes. 11 is a brake device support arm, and 1
2 is a horizontal beam of the bogie frame. Reference numeral 29 is a thrust receiver flange fixed to the first axle 21. Reference numeral 13 is an axle bearing that supports the load of the vehicle, and 14 is an axle bearing seat. Figure 7
Is a plan view of another embodiment of the present invention, in which a first axle 33, a second axle 34, a radial bearing 35, a thrust bearing 36,
The shape of the thrust receiving flange 37 is different from that in the case of FIG. 5, and the characteristic of the structure is that the left axle bearing 13 is on the second axle, which is different from the case of FIG. Although the shape is more complicated than the case of FIG. 5, there is an advantage that the first axle and the second axle can be separated without disassembling the axle bearing.

As described above, the entire structure is simple and can be handled in the same manner as one brake disc per shaft, and can be replaced with a fixed wheel and an axle in a bogie with a conventional structure, and a curve with a small curve radius can be used. Even on roads, it has the effect of providing an independently rotating wheel and axle structure that eliminates slippage of the treads of the wheels.

[Brief description of drawings]

FIG. 1 is a front view showing a conventional wheel for a general railroad vehicle and effective diameters of left and right wheels when an axle is on a rail.

FIG. 2 is a plan view showing a curved road of a railway.

FIG. 3 is a front view showing an example of wheels and axles for a railway vehicle used in a recent commuter car or the like.

FIG. 4 is a plan view showing an example of a structure in which left and right wheels can rotate independently.

FIG. 5 is a plan view showing a structure of a wheel and an axle for a railway vehicle of the present invention.

FIG. 6 is an enlarged view of a part of FIG.

FIG. 7 is a plan view showing the structure of another embodiment of the present invention.

[Explanation of symbols]

 1, 2 Wheels 3 Axles 4, 5 Rails 6 Brake Discs 7 Brake Device 12 Wheels 13 Wheel Bearings 21 First Wheels 22 First Axles 23 Second Wheels 24 Second Axles 25, 26, 35 Radial Bearings 27, 28, 36 Thrust bearing 30 First brake disc 31 Second brake disc

Claims (1)

[Claims] 1. A first axle is provided with a first wheel, a second axle is provided with a second wheel, and the second axle has a hollow structure through which the first axle penetrates. Between the second axle, there is a radial bearing that keeps the shaft center of both shafts and a thrust bearing that keeps the axial position of both shafts, the first axle has a first brake disc, and the second axle has a second brake disc. A structure of an independently rotating wheel and an axle, which has two brake disks, and the first brake disk and the second brake disk are provided in adjacent positions.