FIELD OF INVENTION
This invention relates to a draft gear for main line/LHB coaches of railways.
PRIOR ART
Draft gears used on the main line/LHB coaches are as such known in the art. The same has been depicted in fig 1. Said draft gears comprising of resilient means such as spring elements in a housing used for both travel modes i.e. tension and compression. The housing consists of two striking plates with spring elements therebetween. Upon application of force on the front striking plate, the spring gets compressed between the front and rear striking plates. This causes deflection of the front plate. Thereafter, the front striking plate travels into the housing/pocket. During recoil, front striking plate travels outwards and hits the front stopper on the coach. Similarly, in case of tension rear striking plate moves inward or outward.
The technical problems/disadvantages associated with the above are as follows:
-uncomfortable ride due to jerks caused by striking plates
travelling in draw and buff mode and striking the stoppers of
the pocket during recoil. This results in undesirable sound and
jerk.
-slack either between the pocket and striking plates or between
the interface of draft gear and coupler head.
OBJECTS OF THE INVENTION
The primary object of this invention is to propose a draft gear for main line/LHB coaches of railways which overcomes disadvantages associated with the prior arts.
Another object of this invention is to propose a draft gear for main line/LHB coaches of railways having no free slack between the coupler head and draft gear interface or between stopper of the coach pocket and striking plates of the draft gear.
Further object of this invention is to propose a draft gear for main line/LHB coaches of railways having complete axial travel of the spring column.
Still another object of this invention is to propose a draft gear for main line/LHB coaches of railways having ±18° horizontal and ± 5° vertical swing.
STATEMENT OF INVENTION
According to this invention there is provided a draft gear for main line/LHB coaches of railways comprising of a housing accommodating a pack of compressive resilient means connected to a pack of tensile resilient means wherein a wedge assembly is disposed between the housing and rear stopper.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Further objects and advantages of this invention will be more apparent from the ensuing description when read in conjunction with the accompanying drawings and wherein:

Fig. 1 shows: conventional draft gears.
Fig. 2 shows: Top view of draft gear of the present invention. Fig. 3 shows: perspective view of draft gear of the present invention. Fig. 4 shows: sectional view of draft gear of the present invention. Fig. 5 shows: side elevation of draft gear of the present invention.
DETAIL DESCRIPTION OF THE INVENTION WITH REFERENCE TO THE ACCOMPANYING DRAWINGS;
Reference may be made to the accompanying drawings wherein the draft gear comprising of a housing (4) accommodating a pack of compressive resilient means comprising of a plurality of compression pads (5)/ springs separated by plate as shown in fig. 2. Further, the draft gear is having a fork head (3) disposed between front stopper (1) and adjacent to the housing having a bolt connecting its upper and lower part (as shown in fig. 4) and fixedly/detachably attached to the fork head.
Further, a pack of tensile resilient means is provided between end plate (9) and center plate of the housing in which the pack comprising of a plurality of compression pads (5')/springs separated by plate as shown in
fig. 4. A linear busing (14) is provided in the housing for linear guiding. The compressive and tensile resilient means are held tightly by means of for example bolt and nut (8 and 7).
A wedge assembly is also provided between tapered side (15) of the housing and rear stopper (2). The wedge assembly comprising of wedge housing supporting a wedge block (11) therein held tightly to each other by a bolt and nut (12 and 13). Tightening of the bolt causes upward sliding of the wedge block inside the wedge housing, which exerts force on the tapered side of said housing and wedge assembly.
Thus allowing no motion between the housing and the front and rear stoppers of the pocket (1 and 2). Therefore, the motion is restricted within the housing and to the said resilient means. This causes elimination of free slack.
The draft assembly is incorporated inside the coach pocket followed by positioning of the wedge assembly.
The working principle
The draft gear works in both the modes of travel i.e. Tension(Draw) and Compression (Buff) mode.
When there is no force applied on the Fork Assembly, the draft gear remains in the assembled condition.
The Buff Mode
As can be seen in the figure, when force is applied in the axial direction on the Fork assembly in compressive mode, the compression spring pack gets compressed between the center plate of the main body (4) and Fork Assembly.
By virtue of this compression and decompression of the compression spring pad, energy gets absorbed, the amount of which is proportional to the impacted energy.

During this travel the main bolt (7) also travels in the compressive axial direction. This causes decompression of the tension spring pack.
The Draw Mode
As can be seen from the figure when force is applied in the axial direction in tensile mode, the force gets transferred from the Main bolt (7) to the Main nut (8) and finally to the End plate (9). Thus compressing the tension spring pack between the end plate (9) and the center plate of the main housing (4).
By virtue of this compression and decompression of the compression spring pad, energy gets absorbed, the amount of which is proportional to the impacted energy.
It is to be noted that the present invention is susceptible to modifications, adaptations and changes by those skilled in the art. Such variant embodiments employing the concepts and features of this invention are intended to be within the scope of the present invention, which is further set forth under the following claims:-

WE CLAIM
1. A draft gear for main line/LHB coaches of railways comprising
of a housing accommodating a pack of compressive resilient
means connected to a pack of tensile resilient means wherein a
wedge assembly is disposed between the housing and rear
stopper.
2. A draft gear for main line/LHB coaches of railways as claimed
in claim 1 wherein the compressive and tensile resilient means
comprises a plurality of compression pads/springs separated by
plate (s).
3. A draft gear for main line/LHB coaches of railways as claimed
in claim 1 or 2 wherein the compressive and tensile resilient
means are connected to each other by means of nut and bolt.
4. A draft gear for main line/LHB coaches of railways as claimed
in any of the preceding claims wherein the tensile resilient
means is provided between end plate and center plate of the
housing.

5. A draft gear for main line/LHB coaches of railways as claimed
in any of the preceding claims comprising of a fork head having
a bolt connecting its upper and lower part, which is disposed
between front stopper and adjacent to the housing.
6. A draft gear for main line/LHB coaches of railways as claimed
in any of the preceding claims wherein the wedge assembly
comprising of a wedge housing accommodating a wedge block
held tightly to each other by means of a nut and bolt.
7. A draft gear for main line/LHB coaches of railways as claimed
in any of the preceding claims wherein the housing is having a
bushing for linear guiding.
8. A draft gear for main line/LHB coaches of railways substantially
as herein described with reference to the accompanying
drawings.