JPH0455041Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to rails for various railway vehicle curves that are also applied to urban transportation systems, such as streetcars.

(Prior Art) To explain the curve running function of the conventional railway vehicle curved rail, as shown in FIG. Wheels 5a and 5b of a railway vehicle running on the same axis have wheel side treads 6a and 6b fixed to both ends of the same axle 4 and having a predetermined taper angle α in the width direction with a small diameter on the outside, and are relatively small. Inside and outside curved rail 1a with radius of curvature R,
When a railway vehicle runs on a curve on 1b, the second
As shown in FIG. The contact point Po radius ri of the wheel 5a decreases,
The radius ro of the contact point Pi of the outer wheels 5b increases, and the contact point radius difference ro-ri between the wheels 5a and 5b, that is, the rotational radius difference, caused by the movement of the contact point P when the railway vehicle runs on a curve causes them to fit on the same axle. It is structured so that both fixed and fixed wheels can run in a rolling state according to the radius of curvature of the curved rail on which the wheels are installed, and the radius difference at the contact point position of the two wheels is expressed as ro-ri= The relationship 2br/R holds true, and r is
The average value of ri and ro is approximately equal to the contact point radius during straight running, and b corresponds to 1/2 of the contact point spacing at that time,
If this relationship holds true for any radius of curvature R, both wheels will maintain a perfect rolling state and the vehicle will be able to travel in a stable curve.

The means for maintaining the rolling state is usually
) Increasing the slope of the wheel tread, ) Providing a moving gap (slack) between the wheel and the curved rail,
) There are methods such as laying curved rails with an inclination toward the center of the track, but these methods must be selected appropriately based on normal running stability, etc. On the other hand, the contact position of the wheels changes during running. However, it is necessary to determine the shape of the wheel tread so that the contact surface pressure does not become excessive. Taking these into consideration, the conventional system described above has rail heads 2a and 2b as shown in FIG. 2B. Due to the shape constraints of the rail side treads 3a, 3b, it is not possible to increase the amount of change in the width direction of the contact points of the wheel side treads 6a, 6b, and therefore, the difference in turning radius is small and the difference in travel distance between the two wheels cannot be increased. There is a limit to how large it can be made, and for the above reasons, the minimum radius of curvature R of the rail is about 100m, and if a vehicle is to pass through an even smaller curve, it is necessary to compensate for this by wheel creep. Then,
If this limit is exceeded, slippage will occur between the contact surfaces of the wheels and the rails, causing strain on the rails and wheels, impairing smooth running.

(Problems to be Solved by the Invention) In the conventional curved rail for railway vehicles, in the conventional system, the relative relationship between the wheels and the curved rail causes a large difference in the turning radius of the wheels at the contact points on the inner and outer rail sides when traveling on a curve. The difference in travel distance between the two rotating wheels is small, making it difficult to maintain the rolling state when traveling on short curves.

In other words, it is difficult for a vehicle to pass stably on a curved rail with a radius of curvature of 100 m or less, and if it is forced to pass, it may cause an increase in pressure at the contact point, abnormal wear of the curved rail and wheel flange, and noise pollution due to squeaking noise. Various problems arise, and there are problems such as a significant loss of stability when the vehicle is running.

(Means for solving the problem) The present invention is a rail for curved railway vehicles developed to solve the above-mentioned problems. By creating a shape that is gradually lowered toward the side and providing a sloped tread on the rail side tread that moves the contact point of the wheel side tread to the outside of the track, the turning radius of both the inner and outer wheels when the vehicle runs on a curve is improved. By increasing the difference, the rolling performance of the wheels and the running performance of the vehicle on curved rails with a relatively small radius of curvature are improved.

(Function) The rail side tread of the rail head on the inner track side curved rail is shaped to be gradually lowered toward the track center side, and the slope provided on the rail side tread moves the contact point of the wheel side tread to the outside of the track. The tread increases the distance between the contact points of both the inner and outer wheels when the railway vehicle runs on a curve, and the difference in the radius of contact between the two wheels, that is, the difference in turning radius, increases. Even in this case, perfect rolling movement of both wheels is ensured, and the railway vehicle runs stably.

(Embodiment) Fig. 1 shows an embodiment of the present invention, in which 1a is an inner curved rail, 1b is an outer curved rail, 5
a and 5b are wheels of a railway vehicle, both wheels 5
a, 5b are fitted and fixed to both ends of the same axle 4, and the wheel treads 6a, 6b of the wheels 5a, 5b are formed at a predetermined taper angle α with a smaller diameter on the outside, and have an outer track curve. The rail side tread 3b of the rail head 2b on the rail 1b is the same as the conventional one, and in the present invention, the rail side tread 3b of the rail head 2a on the inner curved rail 1a is
A is made into a shape that is gradually lowered toward the center of the track by cutting or other means (see the chain line in Fig. 1A), and the contact point of the wheel side tread 6a with the rail side tread 3a is moved to the outside of the track (wheel Taper angle in the width direction β) Slightly larger than the side tread 6a) Gradient tread 10
The structure includes a.

The embodiment of the present invention has the above-mentioned structure, and its operation will be explained as follows:
When a railway vehicle runs on a curve on the inner curved rail 1a and the outer curved rail 1b, which have a radius of The outer curved rail 1b and the outer wheels 5
The contact point P _L with b is the same as the conventional one, and the inner curved rail 1a and the inner wheel 5a are the same as the conventional contact point.
The contact point P _s has moved significantly outward from P _p , and
For the rotation radius r of the wheel corresponding to the contact point P, the rotation radius r _p at the conventional contact point P _p becomes the rotation radius r _s at the contact point P _L , and when the contact points P _p and P _s are compared in detail, , as shown in FIG. 1A, the wheel tread 6 of the wheel 5a
Due to the relationship between the taper angle α of a and the taper angle β of the slope tread 10a of the inner curved rail 1a, the contact point that could conventionally only be made at the contact point P _p is changed to the outside of the track (that is, closer to the center of curvature). In other words, the taper angle β line of the rail side tread surface 3a on _the inner track side curved rail 1a is formed lower than the taper angle α line of the wheel side tread surface 6a by the slope tread surface 10a. This enables the movement of the contact point P _p →P _s , and as a result, r _s < r _i and the difference in rotation radius between the inner and outer wheels 5a and 5b is r _p −
Since r _i <r _p -rs, the difference in the rotation radius between the two wheels 5a and 5b is increased, and the rotation radius on the inner curved rail 1a side is significantly reduced, so that rolling contact between the two wheels is maintained. That is, by r _p −r _s =2br/R, r _p −
If r _s is increased, the radius of curvature R of the curved rail can be set smaller.

The feature of this invention is to modify the shape of the rail side tread of the rail head to move the contact point of the wheel tread, and to set a large difference in the corresponding rotation radius (wheel circumference) between the contact points of both wheels. However, the method of modification is not limited to the above-mentioned embodiment, and various design changes can be made without departing from the gist of the present invention.

As a method for obtaining the wheel rotation radius difference, in addition to the above, increasing the taper angle of the wheel side tread surface,
Wider the laying pitch of the inner and outer curved rails,
Various methods can be considered, such as tilting the inner curved rail toward the outer curved rail and making contact with the wheel side tread on the outside of the track. , there are many drawbacks such as difficulty in rail laying work, which makes practicality a problem.However, the above-mentioned structure of the present invention eliminates these drawbacks and allows railway vehicles to operate even on short curves with a rail curvature radius of about 30 m. It has become possible to stably pass through the area, making it possible to widely handle geographical control for urban transportation.

(Effects of the invention) The present invention has the above-mentioned configuration, and is a slope tread that moves the contact point of the wheel side tread provided on the rail side tread of the rail head on the inner track side curved rail to the outside of the track. This increases the distance between the contact points of both the inner and outer wheels when the railway vehicle runs on curves,
The difference in radius of contact between the two wheels, that is, the difference in the radius of rotation, becomes larger, ensuring perfect rolling movement of both wheels even on curved rails with a relatively small radius of curvature, resulting in stable running and improved running of the railway vehicle. Performance has been significantly improved and versatility has been increased.

[Brief explanation of the drawing]

Fig. 1A is a vertical cross-sectional view of an inner curved rail showing an embodiment of the present invention, Fig. 1B is a longitudinal cross-sectional view showing the overall arrangement of Fig. 1A in the installed state, Fig. 2A, B
2 is a vertical cross-sectional view of a conventional inner curved rail and a vertical cross-sectional view showing the overall layout of the rail when it is installed. 1a...Inner track side curved rail, 2a...Rail head, 3a...Rail side tread, 6a...Wheel side tread, 10a...Slope tread.

Claims (1)

[Scope of utility model registration request] The rail side tread of the rail head of the inner track side curved rail is shaped to be gradually lowered toward the track center side, and a sloped tread is provided on the rail side tread to move the contact point of the wheel side tread to the outside of the track. Railway vehicle curve rail featuring: