EP2103738B1

EP2103738B1 - Frog

Info

Publication number: EP2103738B1
Application number: EP08466022A
Authority: EP
Inventors: Dusan Navratil
Original assignee: Dt-Vyhybkarna A Strojirna AS
Current assignee: Dt-Vyhybkarna A Strojirna AS
Priority date: 2008-03-18
Filing date: 2008-08-19
Publication date: 2012-10-03
Anticipated expiration: 2028-08-19
Also published as: CZ18503U1; EP2103738A3; SK5623Y1; SK32009U1; ES2396464T3; EP2103738A2; PL2103738T3

Description

Technical Fields

The technical solution concerns the frog, mainly for switches of town transport rails.

The Contemporary State of the Art

The hitherto known and used frogs for town transport are simple frogs welded of facing rail casts and slot profile rails of standard quality. The weldment is further welded to the stringer metal plate and side and front metal sheets are welded so as to reach compact unit of the frog. Shallow grooves are made in the frog to safely cover the switch diamond and to arrange fluent and smooth passage. The frog with enclosed rails is usually a part of the switch weldment on the route.
Other known frogs are simple frogs performed as a weldment of a steel block with machined grooves and four facing rails. The frog is usually welded into the route. Wear and tear of the frog material in the field of switch diamond and crossing caused by traffic is repaired to a specific operation status by using the welding-on technology. In case of excessive wear and tear it is necessary to open the ballast and to replace the frog, which is very time- and money-consuming.
There are also known simple frogs performed as a weldment of the cast of the central frog block cast with four casts of wide-web facing rails and four facing rails of standard quality. Shallow grooves are made in the frog to safely cover the switch diamond and to arrange fluent and smooth passage. The frogs are usually welded in the route and the ballast is closed.
There are also used well-known simple frogs, solved as a weldment of the mono block cast with welded-on rails of the given profile. There is a pre-cast groove in the mono-block, processed to specified parameters. The frogs are usually welded in the route and the ballast is closed.
There are also well-known the assembled frogs of rails. The individual parts of the frog are closely connected by detachable pins into one unit. The frog is usually connected on detachable basis with rails using connections and screws and the ballast is closed.
The disadvantage of the above stated weldments of frogs is the fact that the wear and tear of material appears - in case of the above stated known frogs - in the diamond and crossing section is repaired up to specific operation status by using the welding-on technology directly in the route. In case of excessive wear and tear when it is not possible to make repairs any more it is necessary to open the ballast and to replace the frog, which is very time- and money-consuming.
EP-A-143 289 shows a frog representing the closest prior art and showing the features of the preamble of claim 1.
The disadvantage of assembled frogs of rails is the possible slackening of pins and change of required geometric position of individual parts of the frog. For performing service or repairs and replacement of parts it is necessary to open the ballast and to replace the frog, which is very time- and money-consuming.

Technical Solution Base

The task of the technical solution is to eliminate to the maximal possible extent the imperfections of known versions of frogs as well as to create a frog of simple construction allowing easy replacement of their worn-down parts without opening the rail parts.
This can be reached to a significant extent by a frog based on this technical solution, based mainly on the fact that it includes an external part following connection rails and an internal part with crossing, which is pushed-placed in the external part recession and it is connected with it on detachable basis.
From the point of view of the internal part setting it seems favourable for the fronts of the internal part to be of wedge shaped form with matching treated recession fronts in the external part.
In consideration of reliable fixation of the internal part, the external and internal parts are connected on detachable basis using inserts flushed in gaps between the sides of the external part and longitudinal grooves on sides of the internal part, while the inserts are equipped with holes for screws with their nuts placed in shaped grooves made in the external part recession bottom and continuing the assemblage holes leading out of the external part.
It is favourable if the gap and the insert are wedge-shaped for reliable securing of the internal part.
It is purposeful - in consideration of resistance - for at least one internal part to be made of abrasion-resistant steel, mainly bainitic steel.
In consideration of easy dismantling it seems favourable for the insert and the internal part to be equipped with continuous threaded holes.
It is favourable - in consideration of pollution - for the assemblage holes and continuous threaded holes to be blinded.

List of Figures in Drawings

The technical solution will be explained in detail using drawings, where Fig.1 schematically shows the view of the frog, Fig.2 shows the detail of internal and external part of the frog and Fig.3 shows a detail of the external part of the frog with removed internal part.

Description of Samples

As you can see from the figures enclosed, the frog includes a bigger part, connected with connection rails 2. The recession 3 made in the external part 1 houses a push-placed internal part 4 with crossing 5. For good setting it seems favourable for the fronts 6 of the internal part 4 to be of wedge shaped form with matching treated recession fronts 7 of the recession 3. The internal part 4 with crossing 5 is connected on detachable basis with the external part 1 using the inserts 8, arranging side settings of the internal part 4. The inserts 8 are recessed into gaps 9 between side walls 10 of the external part 1 a longitudinal grooves 11 on side walls 12 of the internal part 4. Inserts 8 are equipped with holes 13 for screws 14, with their nuts 15 inserted in shaped grooves 16 made in the bottom 17 of the recession 3 of the external part 1, while the shaped grooves 16 house - from the outer side of the external part 1 - the assemblage holes 18, ideally of round shape for round-shaped nuts. The assemblage holes 18 lead from the outer side of the external part 1 to shaped grooves 16._
For better settlement of the internal part 4 it is suitable for the gap to be wedge-shapes for wedge-shaped inserts 8. The material for external and internal parts 1, 4 should be abrasion-resistant, for example bainitic steel.
So as to make dismantling easier, the inserts 8 and the internal part 4 house threaded holes 19. In consideration of possible pollution it is suitable for the assemblage holes 18 and threaded holes 19 to be blinded by covers not shown in the example.
In the course of assemblage, the internal part 4 is inserted to the recession 3 of the external part 1, through assemblage holes 18 there are inserted the inserts 8 and screws 14 to shaped grooves 16 and to the gap 9 - they pass up to the inserts 8 and they are screwed to nuts 15 and tightened, which means that the position of the internal part 4 is secured.
In the course of dismantling, the screws are screwed out - it does not matter if they break. Then, non-displayed screws are screwed into continuous threaded holes 19 and by their tightening, the internal part 4 and inserts 8 move out of the recession 3 of the external part. The nut 15 is pushed - using the assemblage holes 18 - to the extended part 20 of shaped grooves 16, from where it can be easily taken out. That is the end of dismantling.

Industrial Applicability

The frog can be favourably used in switches of town tram transport.

Claims

Frog, mainly of a rail switch of town transport, including an external part (1) continuing connecting rails (2) and an internal part (4) with crossing (5) placed in a recession (3) adjusted in the external part (1) and connected with the external part (1) on detachable basis, characterised in that the external part (1) and the internal part (4) are connected on detachable basis using inserts (8) recessed into gaps (9) between side walls of the external part (1) and longitudinal grooves (11) on side walls (12) of the internal part (4), while the inserts (8) are equipped with holes (13) for screws (14), with their nuts (15) inserted in shaped grooves (16) adjusted in the bottom (17) of the recession (3) of the external part (1) and continuing assemblage holes (18) leading out of the external part (1), said screws (14) being screwed to said nuts (15) and tightened, thereby securing the position of the internal part (4).
Frog according to claim 1, characterised by the fact that faces (6) of the internal part (4) are of wedge shape and there are accordingly adjusted even the fronts (7) of the recession (3) in the external part (1).
Frog according to claim 1, characterised by the fact that gaps (9) are wedge-shaped for the wedge profile of inserts (8).
Frog according to claims 1 and 2, characterised by the fact that at least the internal part (4) is made of abrasion-resistant steel, mainly bainitic steel.
Frog according to claim 1, characterised by the fact that the insert (8) and the internal part (4) are equipped with continuous threaded holes (19).
Frog according to claims 1 and 5, characterised by the fact that the assemblage holes (18) and continuous threaded holes (19) are blinded.