GB2293847A

GB2293847A - Track machine - discharges material for formation protection layer by screw conveyors

Info

Publication number: GB2293847A
Application number: GB9520528A
Authority: GB
Inventors: Josef Theurer; Herbert Woergoetter
Original assignee: Franz Plasser Bahnbaumaschinen Industrie GmbH
Current assignee: Franz Plasser Bahnbaumaschinen Industrie GmbH
Priority date: 1994-10-05
Filing date: 1995-10-04
Publication date: 1996-04-10
Anticipated expiration: 2015-10-04
Also published as: DE19535230A1; GB9520528D0; FR2725461B1; ITMI951973A1; IT1277649B1; FR2725461A1; AT406967B; GB2293847B; ATA189094A; ITMI951973A0; DE19535230B4

Description

1 A MACHINE FOR FORMING A FORMATION PROTECTION LAYER OF A TRACK 2293847

The invention relates to a machine for forming a formation protection layer of a track, comprising a machine frame supported on on-track undercarriages and connected to a track lifting unit, and a device for inserting additional materials onto the formation.

A machine for cleaning the ballast of track beds and simultaneously stabilizing the formation is already known according to AT 294 898 B, comprising a machine frame supported at each end on on-track undercarriages. The front excavating chain of a total of two excavating chains which is guided through under the track serves to take up the track ballast and discharge the same into a screening unit. The following second excavating chain is provided to remove and take up the formation in a certain layer thickness. The excavated earth is conveyed upwards and falls onto a conveyor belt by which the ballast residues accumulating from the screen are simultaneously transported. This material is then deposited in a conveyor device which may be fed by a receptacle holding additional materials and bonding agents. The resulting mixture of earth, ballast residues, additional materials and bonding agents is discharged in the track bed by means of a flexible jib ahead of the discharge site of the cleaned ballast, in the working direction, and is intermixed by means of a rotating body. The material is then graded and consolidated by an oscillating plate.

Further, there is known - according to EP 0 135 478 Al a method for stabilizing soft ground in order to improve its bearing capacity. In this case, after the removal of the layers covering the formation, the natural soil lying beneath 2 is prepared using the local mixing process, in which bonding agents, such as cement and lime, are incorporated and water and reinforcing particles are added.

A method and a device for consolidating the surface of a formation layer is described by CH 595 512 B. Here, diffusible rigid foam in the unfoamed form is laid on top of the formation and is foamed to form a load-bearing joint-free strip.

Finally, yet another machine for formation rehabilitation is known through DE 93 19 958.9 Ul, in which a charging hopper having a dosing screw is provided above a conveyor belt for inserting formation gravel, for the dosed discharge of lime onto the formation gravel lying on the conveyor belt. The formation gravel covered with lime is then discharged by means of another conveyor device onto the formation, and is graded and consolidated.

The object of the present invention is now to provide a machine of the type previously defined, with which improved and uniform insertion of the additional material into the track substructure is possible.

This object is achieved according to the invention with the machine described in the introduction, in that the device for inserting additional materials is designed as a screw conveyor, arranged beneath the track and extending at an angle to the longitudinal direction of the machine and horizontally, a cylindrical feed duct supporting a feed screw being provided with a number of discharge openings which are spaced apart from one another in the longitudinal direction of the said feed duct.

Uniform distribution of the additional material over the whole width of the formation is ensured with this construction, while troublesome dust formation is also 3 advantageously avoidable at the same time. Uniform distribution over the entire cross-section of the formation is also ensured by the transverse delivery by means of the feed screw if, as a constructional simplification, the additional material is only supplied at one end of the screw conveyor the end remote from the middle of the machine and therefore more easily accessible. By appropriately selecting the size of the discharge openings in conjunction with varying the speed of rotation of the feed screw, if appropriate, the amount of additional material delivered can be varied.

Other advantageous developments of the invention emerge from the subclaims.

The invention is described in more detail in the following with the aid of an exemplary embodiment shown in the drawing, in which Fig. 1 shows a side view of a machine for forming a formation protection layer of a track, comprising a device for inserting additional materials, Fig. 2 shows an enlarged partial side view of the device for inserting additional materials, Fig. 3 shows an enlarged plan view of the aforementioned device in the direction of arrow III of Fig. 2, Fig. 4 shows an enlarged partial view of a screw conveyor of the device, and Fig. 5 shows a cross-section according to the section line V in Fig. 4.

A machine 1 shown in Fig. I has a machine frame 3 supported on on-track undercarriages 2, with which machine frame there are associated an excavating chain 4 for taking up 4 ballast 5 of a track 6 which is to be cleaned and a screening unit 7 for cleaning the taken-up ballast. A depositing conveyor belt 8 which may be swivelled in the horizontal plane is provided for discharging the cleaned ballast onto the track 6. The track 6 can be lifted in the region of a ballastless renewal gap 10 with the aid of two vertically adjustable track lifting units 9. The machine 1 is designed to travel continuously under the power of a motive drive 11 in the working direction shown by an arrow 12. The power is supplied by means of a central power plant 13.

Various working units for stabilizing and rehabilitating a formation 14 are provided in the region of the ballastless renewal gap 10. The said working units essentially comprise a scarifying and mixing unit 15, a device 16 for inserting additional materials and an unrolling mechanism 17. This serves to unroll a geo-plastic 18 from a supply roll.

As Fig. 2 and 3 particularly show, the device 16 for inserting additional materials is composed of two screw conveyors 19 arranged beneath the track 6 and extending at an angle of 900 to the longitudinal direction of the machine and horizontally. Each screw conveyor 19 is associated with one machine half 20 - each machine half being situated opposite the other at right angles to the longitudinal direction of the machine - wherein ends 21 of the two screw conveyors 19 located in the middle of the machine are arranged so as to overlap one another with respect to the longitudinal direction of the machine. This overlap region expediently extends over a length of about 200 to 400 mm.

Associated with each screw conveyor 19 at the end 22 remote from the middle of the machine is a feed opening 24, connected to a transport pipeline 23, for delivering the additional material. A drive 25 serves to rotate a feed screw 27 of the screw conveyor 19 which is mounted so as to be rotatable in a feed duct 26.

AS Fig. 4 and 5 particularly show, the feed duct 26 has on its underside facing towards the formation 14 a number of discharge openings 28 which are spaced apart from one another in the longitudinal direction of the screw. The feed duct 26 is enclosed by a cylindrical dosing cover 29 which is arranged coaxially with respect to an axis 30 of the feed screw 27 and is mounted so as to be rotatable. The dosing cover 29 is similarly provided with a number of further discharge openings 31, spaced apart from one another in the longitudinal direction of the axis, which coincide with the first-mentioned discharge openings 28 of the feed duct 26 when the dosing cover 29 is appropriately rotated relative to the feed duct 26.

Each screw conveyor 19 is detachably joined in the region of the drive 25 to a carrier frame 32 which is mounted vertically adjustably on the machine frame 3. The aforementioned scarifying unit 15 and a mixing unit 33 for mixing the loosened formation 14 with the supplied additional materials are also fixed to this carrier frame 32. Provided above the device 16 for inserting additional materials is a cyclone separator 34 with which a conveying screw 35 connected to the transport pipeline 23 is associated. The cyclone separator 34, to which a filter unit 36 is connected, is connected by a supply pipeline 37 to storage receptacles 38 for storing the additional material.

The additional material, e.g. cement, drawn in through the cyclone separator 34 is delivered by the conveying screw 35 to the two transport pipelines 23 and is thereby supplied to the two feed screws 27. The feed screws 27 which are set rotating by the respective drives 25 convey the additional material at right angles to the longitudinal direction of the machine up to each opposite end 21. In the course of this the additional material falls through the discharge openings 28 and 31 of the feed duct 26 and the dosing cover 29 onto the formation 14 which has been loosened by the scarifying unit 6 15. Water can also be supplied as required by means of another supply pipeline 39. The amount of additional material discharged onto the formation 14 can be varied by altering the speed of rotation of the feed screw 27 and/or by appropriately rotating the dosing cover 29.

In the event that the supply of another additional material, such as lime, is desired, either the number of screw conveyors 19 can be doubled or a single screw conveyor 19 extending over the whole formation width can be used for each additional material.

Claims

CLAI MS

7 1. A machine for forming a formation protection layer of a track, comprising a machine frame supported on on-track undercarriages and connected to a track lifting unit, and a device for inserting additional materials onto the formation, characterized in that the device for inserting additional materials is a substantially horizontal screw conveyor, arranged beneath the track and extending at an angle to the longitudinal direction of the machine, and comprising a cylindrical feed duct supporting a feed screw, the feed duct being provided with a plurality of discharge openings which are spaced apart from one another in the longitudinal direction of the said feed duct.
2. A machine according to claim 1, characterized by a cylindrical dosing cover, enclosing the feed duct and arranged coaxially thereto, the said dosing cover being mounted so as to be rotatable about the common axis and being provided with a plurality of further discharge openings arranged to coincide with the discharge openings of the feed duct.
3. A machine according to claim 1 or 2, characterized 8 in that the said device comprises two said screw conveyors, each associated with one half of the width of the machine.
4. A machine according to claim 3, characterized in that the ends of the two screw conveyors located in the middle of the machine are arranged so as to overlap one another with respect to the longitudinal direction of the machine.
5. A machine according to any one of claims 1 to 4, characterized in that there are associated with the or each screw conveyor at the end remote from the middle of the machine a feed opening connected to a transport pipeline for delivering the additional material into the feed duct, and a drive for rotating the feed screw.
6. A machine according to claim 5, characterized in that the or each screw conveyor is detachably joined, in the region of the said drive, to a carrier frame which is mounted vertically adjustably on the machine frame.
7. A machine according to any one of claims 1 to 6, characterized in that a cyclone separator is provided above the said device for inserting additional 9 materials, with which cyclone separator is associated a conveying screw connected to a transport pipe for c. onveying the said materials to the said device.
8. A machine for forming a formation protective layer of a track, substantially as herein described with reference to the accompanying drawings.