CLIAMS:1. A rail-track switching system for switching rail guided vehicle from a first track to a second track, said rail-track switching system comprising:
? a pair of stock rails fixed on a base;
? a pair of tongue rails slidably disposed between said pair of stock rails;
? a leading stretcher bar; wherein said leading stretcher bar is disposed between said pair of tongue rails and provided with a pair of clamping elements configured on an end portions of said leading stretcher bar for clamping said leading stretcher bar; and
? at least one following stretcher bar disposed at pre-determined distance from said leading stretcher bar and between said pair of tongue rails,
wherein said following stretcher bar comprises a pair of stretcher elements functionally coupled to each other and said tongue rails and adapted to move collectively together and independently relative to each other along the longitudinal axis thereof to change longitudinal dimension of said following stretcher bar for facilitating independent movement of each tongue rail of said pair of tongue rails relative to stock rails, said pair of stretcher elements are functionally coupled to each other by a stretcher conduit adapted to slidably receive a first end portion of each of said stretcher elements.

2. The rail-track switching system as claimed in claim 1, wherein said pair of clamping elements are configured operatively below said leading stretcher bar.

3. The rail-track switching system as claimed in claim 1, wherein said stretcher conduit further comprises a barrier disposed within said stretcher conduit for averting movement of said stretcher elements beyond a predetermined distance within said stretcher conduit.

4. The rail-track switching system as claimed in claim 1, wherein said stretcher elements are rigid bars.
5. The rail-track switching system as claimed in claim 1, wherein a point machine connected to said leading stretcher bar is adapted to facilitate the longitudinal displacement thereof, said point machine further adapted to detect proper contact between one of said pair of tongue rails and one of said pair of stock rails that are disposed adjacent to each other. ,TagSPECI:FIELD OF DISCLOSURE
The present disclosure relates to a field of a railway tracks for a rail-guided vehicle, particularly to a rail-track switching system for switching track of a rail-guided vehicle from a first track to a second track.
DEFINITION
? A point machine is an electric motor that facilitates the longitudinal movement of
• a leading stretcher bar; and
• a pair of tongue rails coupled to the leading connecting bar.
? The leading stretcher bar is a rigid bar coupled to both the tongue rails and disposed there-between to maintain the separation between the tongue rails;
? a first and second following stretcher bars (conventional) are rigid bars disposed downstream of the leading stretcher bar and coupled to both the tongue rails and disposed there between to maintain the separation between the tongue rails.
? Rail-guided vehicle refers to any vehicle that may be guided by rails, for example, railway locomotive.
BACKGROUND
A rail-guided vehicle track mainly consists of stock rail. A tongue rail arrangement is disposed between the stock rails for guiding and switching the track of the rail-guided vehicle from one track to another, such an arrangement is available at a rail-guided vehicle junction or at a spur or siding branches. This arrangement is also called as a railroad switch, a turnout, or points. The tongue rail arrangement is formed by a pair of linked tapering rails lying between the diverging outer rails or stock rails. The tongue rail arrangement also called as points, or switch can be moved laterally into one of two positions to direct a rail-guided vehicle towards the straight path or the curved path. One of more stretcher bars are configured between the two tongue rails. The connecting bars (or stretcher bars) are rigid and maintain the specific lateral distance between the tongue rails. Conventionally, the stretcher bars are of following types: a leading stretcher bar, a first following stretcher bar, a second following stretcher bar and a third following stretcher bar which is now replaced by a spring-operated device in order to reduce the load on the point machine. The point machine is responsible for the longitudinal movement of the leading stretcher bar and guiding the wheels of the rail-guided vehicle on the same track or in changing the track. During the passage of the rail-guided vehicle from the point track, one of the tapered end of the tongue rail is in contact with the stock rail and is secured in its position by the point machine such that there is no movement of the tongue rail during the passage of the rail-guided vehicle. The first tongue rail that is in contact with the stock rail is said to be in ‘closed switch condition’. The second tongue rail that is away from the stock rail is said to be in ‘open switch condition’.
The conventional type Over Riding Switches (ORS) are not provided with clamp lock type point machines, while the modern Thick Web Switches (TWS) on which clamp lock type point machines can be provided. It is observed that in the conventional over riding switch arrangement, rigid type stretchers bars are provided and there is no provision for locking open end of switch, whereas for Thick Web Switch (TWS) arrangement the open end of switch may be clamp locked for which the first and second following stretcher bars are eliminated from the standard design.
The point machine detects contact between the tongue rail and the stock rail at and around the leading stretcher bar only. However, this does not ensure proper contact between the tongue rail and the stock rail at regions in and around the first and second following stretcher bar respectively. This improper contact may occur due to intentional or un-intentional insertion of an object between tongue rail and stock rail and this may lead to derailment of rail-guided vehicle, which is not desired.
However, for maintaining speeds at and above 140 Kmph, the points have to be provided with thick web switches with clamp lock type point machines. Hence, there is a need to provide a stretcher bar arrangement for rail guided vehicles that averts the drawbacks associated with the conventional tongue rail arrangement and that are stable even in case rail-guided vehicles at high speed exceeding 140 Kmph passing over the tongue rail arrangement, thereby enabling rail-guided vehicles to achieve higher speeds during turning and passing over the tongue rail arrangement. Further, there is a need for a first following stretcher bar and a second following stretcher bar arrangement that prevents accidents, derailment during turning and ensures safety.
OBJECTS
Some of the objects of the present disclosure aimed to ameliorate problem of the prior art or to at least provide a useful alternative are listed herein below.
It is an object of the present disclosure to avert the drawbacks associated with conventional stretcher bar switching system.
Another object of the present disclosure is to provide a rail-track switching system that can retain first following stretcher bar and second following stretcher bar in the standard design of Thick Web Switch assembly even when clamp lock type point machine has been provided.
Yet another object of the present disclosure is to provide a rail-track switching system that detects the object inserted between the tongue rail and stock rail at first following stretcher bar & second following stretcher bar and hence prevent derailment of the rail-guided vehicle.
The other objects and advantages of the present disclosure will be more apparent from the following description when read in conjunction with the accompanying figures, which are not intended to limit the scope of the present disclosure.
SUMMARY
The present disclosure provides a rail-track switching system for switching rail guided vehicle from a first track to a second track for obviating one or more shortcomings of the conventional rail-track switching system.
In accordance with the present disclosure, the rail-track switching system comprises:
? a pair of stock rails secured on a base that guides the rail-guided vehicle;
? a pair of tongue rails slidably disposed between the pair of stock rails that facilitate the rail-guided vehicle to switch from one track to another;
? a leading stretcher bar; wherein the leading stretcher bar is disposed between the pair of tongue rails and provided with a pair of clamping elements configured on an end portions of the leading stretcher bar for clamping the leading stretcher bar; and
? at least one following stretcher bar disposed at a pre-determined distance from the leading stretcher bar and between the pair of tongue rails.
In accordance with the present disclosure, the following stretcher bar comprises a pair of stretcher elements functionally coupled to each other and said tongue rails and adapted to move collectively together and independently relative to each other along the longitudinal axis thereof to change longitudinal dimension of the following stretcher bar for facilitating independent movement of each tongue rail of the pair of tongue rails relative to stock rails, the pair of stretcher elements are functionally coupled to each other by a stretcher conduit adapted to slidably receive a first end portion of each of the stretcher elements.
Further, the pair of clamping elements are configured below the leading stretcher bar.
Still further, the stretcher conduit further comprises a barrier disposed within the stretcher conduit for averting movement of the stretcher elements beyond a predetermined distance within the stretcher conduit.
Typically, the stretcher elements are rigid bars.

Further, a point machine connected to the leading stretcher bar is adapted to facilitate the longitudinal movement thereof, the point machine further adapted to detect proper contact between one of the tongue rails and one of the stock rails that are disposed adjacent to each other. Still further, in accordance with the present disclosure, the pair of clamping elements that are configured at an end portion of the leading stretcher bar and just below the end portion of the leading stretcher bar, are adapted to engage with a complementary engaging element secured on the base for facilitating clamping of tongue rail in open switch condition.
BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS
A rail-track switching system will now be described with the help of accompanying drawings, in which:
FIG. 1A illustrates a schematic view of a conventional rail-track switching system with tongue rails disposed between the stock rails wherein the tongue rails are arranged such that the rail-guided vehicle follows a straight track;
FIG. 1B illustrates a schematic view of a conventional rail-track switching system with tongue rails disposed between the stock rails wherein the tongue rails are arranged such that the rail-guided vehicle is diverted from the straight track to another track, that is, the vehicle switches track;
FIG. 1C illustrates a schematic view of a conventional rail-track switching system wherein the tongue rails are provided with a leading stretcher bar, a first following stretcher bar, a second following stretcher bar and a spring box coupled to the tongue rails;
FIG. 2A1 illustrates a schematic view of a leading stretcher bar with a clamping mechanism for clamping an open switch tongue rail, wherein clamps are provided in proximity to the ends of the leading stretcher bar and on the lower side of the leading stretcher bar in accordance with an embodiment of the present disclosure;
FIG. 2A2 illustrates a schematic view of one of flexible stretcher bars in accordance with an embodiment of the present disclosure, wherein the flexible stretcher bar comprises of at least a pair of stretcher elements functionally coupled to each other, a stretcher conduit, and a stopper;
FIG. 2B illustrates a schematic view of a rail-track switching system in accordance with an embodiment of the present disclosure, wherein the tongue rails are provided with a leading stretcher bar, a first following stretcher bar, a second following stretcher bar, and a spring box coupled to the tongue rails in which the first and second stretcher bars comprises of at least a pair of stretcher elements functionally coupled to each other and the tongue rails and adapted to move collectively together and independently relative to each other; and
FIG. 3 illustrates a schematic view of a longitudinal displacement of the first following stretcher bar in accordance with an embodiment of the present disclosure.
DETAILED DESCRIPTION
A rail-track switching system of the present disclosure will now be described with reference to the embodiments, which do not limit the scope and ambit of the disclosure.
The embodiments herein, the various features and the advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known components and processing techniques are omitted so that there is no unnecessarily confusion about the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
The description hereinafter, of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.
FIG. 1A illustrates a schematic view of a conventional rail-track switching system 100 with tongue rails (102a, 102b) disposed between the stock rails (101a, 101b) wherein the tongue rails (102a, 102b) are arranged such that the rail-guided vehicle follows a straight track indicated by numeral 104a. The tongue rail 102a is separated from the stock rail 101a by a certain distance. The other straight tongue rail 102b is in contact with the other stock rail 101b. This configuration of the tongue rail 102a with respect to the stock rail 101a is termed as ‘open switch condition’. FIG. 1B illustrates a schematic view of a conventional rail-track switching system 100 with tongue rails (102a, 102b) disposed between the stock rails (101a, 101b) wherein the tongue rails (102a, 102b) are arranged such that the rail-guided vehicle (not shown in the figure) is diverted from the straight track to another track (direction indicated by arrow 104b), that is, the vehicle switches track. For switching the track of the rail-guided vehicle, the tongue rail 102a is brought in contact with the stock rail 101a (as shown in FIG. 1B) whereas the other tongue rail 102b is positioned away from the stock rail 101b. This configuration of the tongue rail 102a with respect to the stock rail 101a is termed as closed switch condition. The tongue rails (102a, 102b) in this position guides the rail-guided vehicle (not shown in the figure) along the direction of the arrow indicated by numeral 104b.
FIG. 1C illustrates a schematic view of a conventional rail-track switching system 100 wherein the tongue rails (102a, 102b) are provided with a leading stretcher bar105a, a first following stretcher bar 105b, a second following stretcher bar 105c and a spring box 105d connected to the tongue rails (102a, 102b) by suitable coupling means (not shown in the figure). A point machine 106 is connected to the leading stretcher bar105a by suitable coupling mechanism 106a. The point machine 106 brings about the displacement of the tongue rails (102a, 102b) by moving the leading stretcher bar105a along its longitudinal axis. The point machine 106 may be one of an electric motor capable of producing sufficient power to bring about the displacement of the tongue rails (102a, 102b) so that the rail-guided vehicle may be directed along one of the tracks (in the directions indicated by the arrows 104a or 104b as shown in FIG.1C) as described hereinabove with reference to FIG. 1A and FIG. 1B. However, the point machine 106 is not limited to be an electric motor and may be other device that is capable of applying pulling and pushing forces for causing movement of the leading stretcher bar105a along its longitudinal axis.
In the conventional rail-track switching system 100, the tongue rails (102a, 102b) are having ends A and B (as shown in FIG. 1A and FIG. 1B) respectively. At any point of time (whether the rail-guided vehicle moves on the same track or switches track) one of the ends (A/ B) is in contact with one of the stock rails (101a, 101b), that is, one of the ends (A/B) of the tongue rail is in closed switch condition while the other end is separated or spaced from the stock rails (101a, 101b) at a certain distance, that is, the other tongue rail is in open switch condition. It is observed that the end A / B of the tongue rails (102a/102b) that is in open switch condition vibrate as the rail-guided vehicle passes over it.In particular, at and above 140 kmph speed of the rail-guided vehicle there is possibility that the open switched tongue rail may get displaced from its position due to the vibrations and may come in close proximity to the stock rail. This condition may again lead to derailment of the rail-guided vehicle.
Further, in accordance with the present disclosure, clamps (207a, 207b) (as shown in FIG. 2A) are provided below the leading stretcher bar to securely hold or clamp the tongue rail (102a/102b) that is in open switch condition to avert the vibrations and hence the displacement of the tongue rail (102a/102b) at end of the tongue rail A or B
FIG. 2A1 illustrates a schematic view of a leading stretcher bar205a with a clamping mechanism for clamping an open switch tongue rail 202a (FIG.2B), wherein clamps (207a and 207b) are provided in proximity to the ends (End ‘A’ and End ‘B’) of the leading stretcher bar 205a and on the lower side of the leading stretcher bar205a in accordance with an embodiment of the present disclosure. The grooves or notches 207c and 207d respectively receive the clamps 207a and 207b, wherein the grooves 207c and 207d have a profile that is complementary to the shape of the clamps 207a and 207b.
In particular, as shown in FIG. 2A1, the clamp 207a is received within the groove 207c such that the end (which is in open switched condition) of the stretcher bar 205a is secured and hence open tongue rail is locked. This ensures that the open tongue rail does not vibrate and move closer to the stock rail when the rail-guided vehicle moves over the tongue rail at speeds of 140 Kmph or higher.
In accordance with the present disclosure, the open switched tongue rail is clamped and hence secured. However, every time when there is need for switching the direction of the rail-guided vehicle passing over the rail-track system, the clamping of the open switched tongue rail has to be removed. This is achieved by moving the tongue rail by using the point machine 206 that moves the leading stretcher bar205a.
To remove the clamping or the clamp from the groove, it is necessary to achieve independent movement of one of the tongue rails (that is in open switch condition) and keeping the other tongue rail static by clamping it. This independent movement of the one of the tongue rail cannot be achieved by use of the conventional rigid first following 105b and second following stretcher bar 105c (according to FIG. 1C).
One-way out is to remove the first following stretcher bar and second following stretcher bars from the tongue rails. However, the inventors have observed that removal of the first following stretcher bar and the second following stretcher bar make the tongue rails in that region susceptible to non-detection of obstruction in this region by the point machine. .
Further, the point machine 206 (according to FIG. 2B) only detects the contact of the leading stretcher bar205a (according to FIG. 2B) and not of the first and second following stretcher bars. Any object that may be inserted either with or without malicious intent may infringe with the displacement of the tongue rails, which in turn may lead to rail-guided vehicle derailment.
In order to overcome any such possibility, the present disclosure provides a first and second following flexible stretcher bar respectively. The flexibility of the first following stretcher bar and the second following stretcher bar is in the sense that the length of the stretcher bar may be varied.
FIG. 2A2 illustrates a schematic view of one of flexible stretcher bars 205b (according to FIG.2B) in accordance with an embodiment of the present disclosure, wherein the flexible stretcher bar 205b comprises of at least a pair of stretcher elements 205b1 and 205b2 functionally coupled to each other, a stretcher conduit 205b3, and a stopper 208. The ends E1 & E2 of the stretcher elements 205b1 and 205b2 respectively are coupled to the tongue rails. With such configuration, the stretcher elements 205b1 and 205b2 are adapted to move collectively together and also independently relative to each other along the longitudinal axis thereof to change longitudinal dimension (length) of the stretcher bar 205b for facilitating independent movement of each tongue rail of the pair of tongue rails relative to stock rails.
In accordance with the present disclosure, the stretcher elements 205b1 and 205b2 are functionally coupled to each other by the stretcherconduit 205b3, the conduit is adapted to slidably receive the free ends E3 and E4 of each of the stretcher elements 205b1 and 205b2, while the opposite ends E1 and E2 of the stretcher elements 205b1 and 205b2 are secured to the tongue rails (not shown in Fig. 2A2).
In accordance with the present disclosure, typically the stretcher elements 205b1 and 205b2 may be simple rods or strips having enough strength to sustain the harsh movements, vibrations and load encountered in rail-systems.
In accordance with the present disclosure, typically the stretcher elements 205b1 and 205b2 are in form of strips made of mild steel or any other metal.
In accordance with the present disclosure, typically the stretcher conduit 205b3 is a tubular enclosure made of metal and has a stopper 208 securely disposed at the center of the stretcher conduit. This stopper 208 is provided for stopping the further movement or insertion of the ends E3 and E4 into the stretcher conduit during the switching of the tongue rails.
Typically, the stretcher conduit 205b3 have a length such that the end portions E3 and E4 of the stretcher elements are always retained inside and never comes out of the stretcher conduit 205b3 in the event of displacement of the stretcher elements 205b1 and 205b2 from the center of the stretcher conduit 205b3.
Typically, the stretcher elements 205b1, 205b2 and the stretcher conduit 205b3 have a rectangular cross-section.
Typically, length and breadth of the stretcher conduit 205b3 is such that the stretcher elements 205b1 and 205b2 or the ends thereof are received within the conduit 205b3 slidably.
Referring to FIG. 2B in conjunction with FIG. 2A1, FIG. 2A2, and FIG. 2B illustrates a schematic view of a rail-track switching system 200 in accordance with an embodiment of the present disclosure, wherein the tongue rails 202a, 202b are disposed with the stock rails 201a, 201b and are provided with a leading stretcher bar205a, a first following stretcher bar 205b, a second following stretcher bar 205c and a spring box 205d coupled to the tongue rails 202a, 202b in which the first and second stretcher bars are flexible stretcher bars as described hereinabove according to FIG. 2A1. The leading bar 205a is coupled to a point machine 206 via a stretcher shaft 206a. The point machine 206 makes it possible to displace the tongue rails 202a, 202b such that the rail-guided vehicle can be directed to straight track 204a or a diverted track 204b.
FIG. 3 illustrates a schematic view of a longitudinal displacement of the first following stretcher bar 205b in accordance with an embodiment of the present disclosure, wherein the longitudinal displacement of the first following stretcher bar 205b is caused by longitudinal displacement of the stretcher elements 205b1 and 205b2 with respect to the stretcher conduit 205b3.
In a first step (I) of FIG. 3 illustrates the stock rail 201a and tongue rail 202a in contact with each other (that is closed switch condition) and the tongue rail 202b separated from the stock rail 201b by distance X1. The first flexible stretcher bar 205b in accordance with the present disclosure connects the tongue rails 202a and 202b to each other. The two stretcher elements 205b1 and 205b2 and the conduit 205b3 are in such a configuration that there is no gap or separation of the stretcher elements from the center or the stopper 208.
When the point machine 206 (not shown in FIG. 3) displaces the tongue rails 202a and 202b by dragging the leading stretcher bar205a, the first following stretcher bar, which is 205 b, is also displaced with it. This leads to displacement of the stretcher element 205b2 towards the stock rail 201b, thereby decreasing the separation between the stretcher element 205b2 and the stock rail 201b to X2 from X1, wherein X1 is greater than X2 (according to a second step (II) of FIG. 3). This creates a gap or separation Y1 between the stopper 208 (in the stretcher conduit 205b3) and the stretcher element 205b2. According to the second step (II) of FIG.3, the clamp that is secured at the open end of switch is unlocked.
In a third step (III) of FIG. 3, both the tongue rails now move together such that the stretcher element 205b1 is now displaced with the tongue rail 202a and the following stretcher bar 205b1 creates a separation X3 between the tongue rail 202a and the stock rail 201a. At the same time the separation X2 between the tongue rail 202b and stock rail 201b is reduced to zero and the two are now in contact with each other (closed switch condition). Further, the gap between the stretcher element 205b2 and the stopper 208 is reduced to Y2.
In a fourth step (IV) of FIG. 3, the gap Y2 between the stretcher element 205b2 and the stopper 208 is reduced to zero by movement of the tongue rail 202a only, wherein during this step the tongue rail 202a is clamped by the clamping mechanism provided in leading connector bar 205a. This creates a separation X4 between the stock rail 201a and the tongue rail 202a which is the open switched condition for tongue rail 202a.
Thus, the following flexible stretcher bars of the present disclosure permits independent movement of the tongue rails.
Thus, the embodiment of the present disclosure accomplishes the objects of the present disclosure and curtails the drawbacks associated with the conventional rail-track switching system.
TECHNICAL ADVANCEMENT
The technical advancements of the tongue rail arrangement of the present disclosure are as follows:
? retained all safety parameters (Housing of Tongue rail & JOH clearance) which were achieved with conventional Overriding Type Switch having fixed following stretcher bars (without clamp lock type point machine) for speeds upto 140 Kmph is being achieved for speeds upto 140 Kmph where Thick Web Switches are to be used with clamp lock type point machines.
? a new tongue rail arrangement with clamping mechanism and the flexible stretcher bars that is able to detect the object inserted between the tongue rail and stock rail; even at the 1st & 2nd stretcher bar, thereby ensuring safety
Throughout this specification the word “comprise”, or variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.
The use of the expression “at least” or “at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the invention to achieve one or more of the desired objects or results. While certain embodiments of the inventions have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Variations or modifications to the formulation of this invention, within the scope of the invention, may occur to those skilled in the art upon reviewing the disclosure herein. Such variations or modifications are well within the spirit of this invention.
The numerical values given for various physical parameters, dimensions and quantities are only approximate values and it is envisaged that the values higher than the numerical value assigned to the physical parameters, dimensions and quantities fall within the scope of the invention unless there is a statement in the specification to the contrary.