WO1999024669A1

WO1999024669A1 - An arrangement for bringing a clamping element from a fastening position to a released position

Info

Publication number: WO1999024669A1
Application number: PCT/SE1998/001993
Authority: WO
Inventors: Lars Erne Holmberg
Original assignee: A. Rosenquist Förvaltnings Ab
Priority date: 1997-11-06
Filing date: 1998-11-03
Publication date: 1999-05-20
Also published as: AU1182499A; SE9704062L; SE509316C2; SE9704062D0

Abstract

The invention relates to an arrangement for moving a clamping element forming part of a clamping unit and movably fastened to a railroad sleeper from a position in which the clamping unit fastens the sleeper to a rail, to a releasing position. The clamping element can be moved in a direction away from (and towards) the rail through the medium of a support means belonging to said clamping unit and fixed in relation to said sleeper, and with the aid of a device that co-acts with the clamping element. The arrangement includes a means (51, 51a') which when the clamping element (3a') is moved in one direction functions to ensure that a stop means (20') will prevent the clamping element (3a') from leaving the clamping unit (3').

Description

TITLE OF INVENTION: AN ARRANGEMENT FOR BRINGING A CLAMPING

ELEMENT FROM A FASTENING POSITION TO A RELEASED POSITION

FIELD OF INVENTION

The present invention relates to an arrangement for moving at least one clamping element from a fastening position, and more particularly to an arrangement that can bring at least one clamping element forming part of a clamping unit and ovably fastened to a railroad sleeper from a position in which it fastens a rail section to said sleeper and to a sleeper releasing or "non-fastening" position.

The clamping unit intended for use in accordance with the present invention includes a clamping element which is adapted for movement towards and away from a rail section through the medium of a support means belonging to the clamping unit and fixed in relation to said sleeper and with the aid of means that co-acts with the clamping element or the like.

More specifically, the invention includes the use of clamping units arranged in pairs on respective sides of a rail section, wherein the two clamping elements of each pair can be moved towards one another so as to take a fixed or fastening position, or away from each other so as to take a releasing or non-fastening position in one and the same sequence.

DESCRIPTION OF THE BACKGROUND ART

Several different embodiments of arrangements for bringing a clamping element fastened to a railroad sleeper and forming part of a clamping unit to a position in which it fastens said rail section to said sleeper are known to the art.

An example of such an arrangement is found in U.S. Patent Publication US-A 3,690,264 and International Patent Publication W095/13427 (International Patent Application PCT/SE94/01042) .

With respect to the properties afforded by an arrangement according to the present invention for moving a clamping element from a fastening position to a releasing position, a generally available and demonstrated arrangement also forms part of the prior art.

This arrangement requires three different working sequences that can be effected by means of three separate activatable means in the form of hydraulic piston-cylinder devices, a first means for gripping and clamping a railroad sleeper at its end surfaces, a second means for lifting a thus clamped sleeper into abutment with a rail section, a third means for moving or displacing a clamping element into a fastening position, and a fourth means for moving a clamping element from a sleeper fastening position to a sleeper releasing position.

Activation of these means requires the arrangement to be stationary in relation to the sleeper during each of these different working sequences. Such an arrangement is illustrated schematically in more detail in Figure 1.

(The arrangement illustrated in Figure 1 is described in more detail in Swedish Patent Application 9602434-4, "Machine for Mounting Fastener Elements to Rails", filed on June 19, 1996) .

SUMMARY OF THE INVENTION

TECHNICAL PROBLEMS

When taking into consideration the technical deliberations that a person skilled in this particular art must make in or- der to provide a solution to one or more technical problems that he/she may encounter, it will be seen that, on the one hand, it is necessary initially to realise the measures and/or the sequence of measures that must be undertaken to this end, and, on the other hand, to realise which means is/are required in order to solve one or more of said problems. On this basis, it will be evident that the technical problems listed below are highly relevant to the development of the present invention.

When considering the present state of the art, particularly with respect to the arrangement described hereinafter with reference to Figure 1, it will be seen that a technical problem resides in providing, with the aid of simple means, conditions which enable one or more clamping elements to be placed on a mobile unit that can be moved or driven along a rail section and therewith move one or more clamping elements from a fastening position to a releasing position, without impeding movement of the mobile unit along said rail section.

It will also be seen that a technical problem resides in the provision of conditions which allow the mobile unit to move freely even when needing to pass joints and the like in said rail section and/or pass filling material located between adjacent sleepers and extending over said sleepers.

It will also be seen that another technical problem is one of creating with the aid of simple means conditions whereby clamping element stop means separate from the clamping unit and intended to prevent movement of the clamping element out of the clamping unit shall be active at least during the sleeper releasing movement of the clamping element.

Another technical problem is one of providing a particular movement sequence for said stop means and a support surface that can face towards a clamping element, and where said movement sequence can be controlled by a scissors-like movement.

Another technical problem is one of providing a simple mechanical link arrangement for adapted control of said move- ment sequence.

It will also be seen that another technical problem resides in creating, with the aid of simple means, conditions which will enable rail sections to be released from underlying sleepers, by releasing all sleeper-associated clamping elements during movement along said rail section.

It will also be seen that a technical problem resides in providing an arrangement with which sleepers intended for mutu- ally parallel rails of a rail section can be released smoothly and consecutively more quickly than is possible with known methods .

It will also be seen that a technical problem resides in re- alising the significance of and the advantages that are afforded by allowing one end-part of a lever to be configured as a stop means and provided with a hooked recess or groove intended for co-action with a curved surface part of a clamping element.

It will also be seen that a technical problem resides in realising the significance of adapting the clamping elements of four mutually opposing clamping units so that all of said clamping elements will be displaced to a releasing position for detachment of the mutually parallel rails from one and the same sleeper.

It will also be seen that a technical problem is one of controlling movement of the stop means by means of a simple link arrangement to a position in which the curved upper part of the stop means will be located somewhat outwardly of a fully extended clamping element during the clamping element extending sequence, and then take a withdrawn or uplifted position.

It will also be seen that a technical problem resides in exe- cuting the movement sequence of said stop means solely by means of the movement pattern of the scissors device.

SOLUTION

With the intention of solving one or more of the aforesaid technical problems, the present invention takes as its starting point an arrangement of the aforedescribed kind with which a clamping element forming part of a clamping unit and movably fastened to a railroad sleeper can be moved from a position in which it secures a rail track to the sleeper to a sleeper releasing position, where said clamping element is adapted for movement in a direction away from (and towards) the rail track through the medium of support means belonging to said clamping unit and fixed in relation to said sleeper, with the aid of means that co-act with said clamping unit, said means being adapted to move the clamping element away from said rails.

The invention proposes the particular use of stop means that are separate from the clamping unit and that are adapted to prevent movement of said clamping elements, via said means, through a distance which is greater than the intended distance for detaching rails from an underlying sleeper.

According to proposed embodiments that lie within the scope of the present invention, the aforesaid stop means may be fixed relative to a mobile unit.

According to one embodiment, the stop means may be movably arranged and adapted to take an active position solely, or essentially solely, during displacement of said clamping elements to a sleeper releasing position.

According to one embodiment, one end-part of a lever is pro- vided with a hooked recess or groove that functions as a stop means and which is adapted for co-action with an outer surface part of the clamping element.

The lever arm will conveniently form part of a link arrange- ment and the clamping elements of at least two mutually opposing clamping units will be capable of moving simultaneously away from and towards each other.

Said means is arranged for movement relative to a chassis, in a direction relating to the longitudinal extension of a rail section.

One end-part of the lever carries a shoulder that can face towards the clamping element and that is fastened to one end of a lever and link arrangement, while the other end can be guided by a guide groove, a link system or like means. One end-part of the lever and link arrangement is adapted to take a position close to a rail section or to a position distanced from said rail section, or, alternatively, to move be- tween an upper and a lower position.

ADVANTAGES

Those advantages primarily afforded by an inventive arrange- ment reside in the provision of conditions whereby a clamping element can be moved to a sleeper releasing position with the aid of means provided for this purpose and where the clamping element is unable to "flip out of" the clamping element if moved beyond this sleeper releasing position. There is used to this end a stop means which is separate from the clamping unit and which becomes active when the clamping element is moved through an excessively long distance.

The primary characteristic features of an inventive arrangement are set forth in the characterising clause of the following Claim 1.

BRIEF DESCRIPTION OF THE DRAWINGS

An embodiment of an earlier known arrangement and exemplify- ing embodiments of inventive arrangements will now be described in more detail with reference to the accompanying drawings, in which

Figure 1 is a perspective view of an earlier known ar- rangement that includes first means for firmly clamping a railroad sleeper whose end surfaces are exposed to said means, a second means for lifting an exposed sleeper into abutment with adjacent rail sections, and a third means which can be activated to move a clamping element of a clamping unit towards (or away from) said rail section in a horizontal direction;

Figure 2 is a perspective view of a mobile unit that can be moved along two mutually parallel rails, wherein said mobile unit is provided on one side with an inventive arrangement constructed for "detaching" a sleeper from a rail section, and also two sleeper attachment arrangements;

Figure 3 is a perspective view of a clamping unit according to Figure 2, and shows the clamping element moved to a "fastening" position;

Figure 4 is a perspective view of a clamping unit with the clamping element in a releasing or "detaching" position;

Figure 5 is a side view of part of a mobile unit with clamping units in an initial position adjacent clamping elements in a clamping mode and shows fixed stop means for impeding movement of respective clamping elements beyond a distance that exceeds the distance required to release a clamping element;

Figure 6 is a side view illustrating means for moving a clamping element from a fastening to a releasing position, with a movable stop means in a sleeper released position; and Figure 7 is a side view illustrating the movable stop means in an active position in which said means is able to prevent the clamping element from moving through a distance which, with a certain dis- tance, exceeds the distance required to release the clamping element.

DESCRIPTION OF A PRIOR ART ARRANGEMENT

Figure 1 thus shows in perspective an arrangement 1 by means of which a clamping element included in clamping unit 3 and movably fastened to a railroad sleeper 2 can be moved to a position in which a rail section 4 is fastened to the sleeper 2.

In this case, the clamping element can be moved towards the rail section 4, and possibly also away from said rail section 4, via clamping means belonging to said clamping unit and fixed in relation to the sleeper 2, with the aid of means co- acting with said clamping element.

The clamping unit 3 and associated clamping elements and support means will be described in more detail hereinafter with reference to Figures 3 and 4.

The arrangement shown in Figure 1 includes on one side of the rail section three different means for performing three separate operations.

These three means operate in co-ordination with means on the other side of said rail section, although not shown in Figure 1.

A first means 5 is adapted for clamping a sleeper 2 through the medium of end-related, exposed planar vertical surfaces, of which the illustrated planar surface 2a is caused to co- act frictionally with a plate 5a that forms a planar surface 5a' for engagement with said means 5, and with a corresponding, opposing co-action between the end-surface of the sleeper not shown in the Figure and a planar surface belonging to said means.

A second means 6 (and a corresponding means adjacent the rail section 4 ' ) is adapted to raise the sleeper 2 into abutment with a pair of overlying rails 4, 4' in said rail section.

A third means 8 is adapted to move the clamping element to a clamping position against the rails 4, 4' (or to a releasing position) .

More specifically, the means 5 is comprised of a first lever arrangement that carries mutually opposing clamping plates, of which one is referenced 5a, that face towards respective exposed end-surfaces of the sleeper 2, of which one end surface is referenced 2a, wherewith said clamping plates are ma- noeuvred into clamping engagement with the sleeper 2 through the medium of side-mounted piston-cylinder devices, of which one is referenced 5c in Figure 1.

The illustrated two-arm lever arrangement uses a horizontal pivot shaft 5b on one side and a corresponding pivot shaft on the other side.

The embodiment shown in Figure 1 also includes two second, side-mounted means, of which one is referenced 6, in the form of a hydraulic or pneumatic piston-cylinder device that functions to lift a sleeper 2 clamped by the first means 5, 5' into abutment with two overlying rails 4, 4' of a rail section.

The arrangement illustrated in Figure 1 also includes third means, of which one is referenced 8. These third means also utilise a two-arm lever system that includes on one end-part of one arm? a support surface 8a adapted for co-action with the clamping element 3a in the clamping unit 3, while the other end-part is activated to rotate about a shaft 8c by means of a piston-cylinder device 8b.

Activation of the first means (5, 5' ) brings the surface 5a into clamping engagement with the surface 2a on one side, and, correspondingly, brings a similar surface on said means into engagement with an opposing surface of the sleeper 2.

The piston-cylinder device 6 is then activated to lift the sleeper 2 into abutment with the rails 4, 4' of said rail section. When this is completed, the third means 8 is acti- vated to bring the clamping element into clamping engagement with said rails.

The clamping elements are released by carrying out said steps in a reverse order with the use of a release arrangement not shown in detail. The present invention relates to this release sequence.

DETAILED DESCRIPTION OF EMBODIMENTS AT PRESENT PREFERRED

Figure 2 is a perspective view of a mobile unit M which can be moved on four wheels along mutually parallel rails 4, 4' of a rail section.

In the illustrated case, the mobile unit is moved with the aid of a working machine or loading machine 9, said machine having an arm 9a which is secured to a part that can rotate in relation to the unit M, through the medium of a shaft 9b.

The mobile unit M includes a chassis to which a clamping de- vice 10 and two schematically illustrated, inventive unclasping devices 11 are attached. The inventive arrangement may be such as to activate simultaneously four clamping elements in each respective clamping unit, such as to bring said clamping elements to a releasing position, wherein said activation is co-ordinated, two and two, for co-action with respective clamping elements at mutually opposing edge parts of a rail section comprising said rails 4 and 4' .

There is nothing to prevent the movement of all four clamping elements to be co-ordinated through the medium of a releasing arrangement or in respect of pairs of clamping units.

For the sake of simplicity, the introductory part of the fol- lowing description will include only one clamping unit.

Since the present invention includes the releasing or unclasping device 11, only this device will be described in more detail hereinafter.

The releasing arrangement 11 comprises a scissors-like device 11 adapted for co-action with the rail 4, and a scissors-like device 11' adapted for the rail 4' of said rail section, each of said devices being of identical construction and mutually co-ordinated, as illustrated in Figure 5.

The two scissors-like devices 11, 11' enable the clamping elements of four clamping units to be moved simultaneously from a fastening or clamping position to a releasing posi- tion.

Each scissors-like device 11, 11' is activated by a respective single piston-cylinder device 12 and 12' .

Figure 5 shows the clamping unit 3 and clamping elements 3a in a fastening mode. The clamping elements 3a shall be moved away from respective rails to a releasing position (not shown in Figure 5) in which they support against a shoulder forming part of a re- spective clamping unit.

However, when a clamping element is moved towards its releasing position, it is possible that the clamping element will pass beyond said shoulder and leave the sleeper support.

In order to prevent said clamping element 3a from being moved by said device through a distance which, with a certain distance "a", is additional to or in excess of the distance "b" required for release purposes, the arrangement includes a stop device which is separate from said clamping element, said stop device being shown in an enlarged part-view of Figure 5.

Figure 5 shows schematically four stop devices 20, 20a, 20b and 20c, each of said devices being disposed on a respective side of respective rails 4, 4' .

In practice, the distance "a" shall be the smallest possible distance and may even be a negative distance "a", i.e. the device is adapted to stop movement of the clamping element 3a slightly before its co-action with said shoulder.

Practical deliberations speak for a positive distance "a", such as a distance of 5-20 mm, preferably of 7-15 mm in the case of certain applications.

The fundamental principles of the invention will be exemplified hereinafter by describing how a clamping element 3a can be moved to a releasing position (Figure 4) and how the stop devices shall be arranged. It will be obvious to the person skilled in this art how this principle can be applied in a double-mode with the use of a scissors-like device, and how to scissors-like devices can be caused to co-act so as to release four clamping elements in one and the same working operation, i.e. two clamping elements for one rail 4 and two clamping elements for the other rail 4' .

The invention includes an embodiment in which four clamping elements can be moved to their respective releasing positions simultaneously, two for each rail, with the aid of a respective piston-cylinder device 12, 12', although it will be understood that this working operation can be effected with the aid of a single piston-cylinder device subsequent to small structural modifications.

Figures 3 and 4 illustrate in perspective the inventive application of a clamping unit 3.

Although Figures 3 and 4 show only one clamping unit 3 active on the right side of a rail, it will be understood that two clamping units are used in practice, one on each side of said rail. Figure 4 shows the clamping element 3a in its rail releasing position, while Figure 3 shows the clamping element 3a in its inwardly moved and fastening position.

The clamping unit 3 is comprised of a springy, steel clamping element 3a mounted in a groove or channel in a plastic member 3b.

The plastic member 3b, together with the clamping element 3a, is displaceably mounted in a holder or support device fastened to the upper surface 2b of the sleeper 2. The arrangement also includes a plastic member 3c that functions as a side isolator.

In the Figure 4 illustration, the clamping element 3a and the plastic member 3b of the clamping unit 3 are shown in a non- clamping or releasing position, with the rail 4 resting loosely on an elastic pad 3e on the upper surface 2b of the sleeper.

In the Figure 3 illustration, the clamping element 3a is shown in a rail clamping and fastening position, with the clamping element 3a and the plastic member 3b in a position in which they co-act with the upper surface part 4a of the bottom flange of the rail 4.

Fundamental to the present invention is the concept of releasing at least two clamping units from the sleeper, by moving two clamping elements 3a and associated plastic members 3b from the position shown in Figure 3 to the position shown in Figure 4 with the aid of one single device 11 (51a) .

The reference to "one single device" shall be interpreted as meaning that the requisite working sequences can be carried out through the medium of the lone co-action between the de- vice and the clamping element or the like during a movement sequence of said device.

In Figure 6, a significant part of this device has been shown to comprise the bottom part 51a of an arm 51.

The invention is based on a particular design of the bottom part 51a of the arm 51 and a particular pattern of movement of said bottom part.

It shall be possible to cause the lowermost part 51a of the arm 51 to be moved mechanically and/or hydrauli- cally/pneumatically towards and into abutment with an outer part 3b' of the clamping element 3a.

In the state of the arrangement shown in Figure 6, it shall be possible for the lowermost part 51a of the arm 51 to move the clamping element from the position shown in Figure 3 to the non-clamping position or releasing position shown in Figure 4, whist moving the corresponding part 51a' of the opposite clamping element 3' to a non-clamping or releasing posi- tion at the same time.

A specific feature is that the clamping elements of four such clamping units 3, 3' and 31, 31' respectively belonging to one and the same sleeper 2 can be moved simultaneously to their respective non-clamping positions.

In the embodiment shown in Figures 5 and 6, said device 11 is comprised of a two-arm lever system with one end-part 51a' of said lever 51' co-acting with the outer part or the like of said clamping element 3a' , while the other end-part 51b' of said lever co-acts with an hydraulic or a pneumatic piston- cylinder device 12.

The pivot shaft 53, 53' of respective levers 51, 51' are po- sitioned above respective clamping units 3, 3' .

The pivot shaft 53' carries bearing means for the arm 51' and is attached to a bracket 54 which is bolted to the chassis of the mobile unit M, such as to enable desired adjustments to be made to the arrangement through the medium of inserts fitted between the bracket 54 and a chassis attachment device or attachment profile.

The bottom end-part 51a' of the lever includes a hook-shaped recess or groove (in the shape of an arcuate surface) , in- tended for co-action with an arcuate outer part 3g' of the clamping element.

It will be seen particularly from Figure 5 that the levers 51 and 51' are included in a scissors-like device, with one lever arm 51' being an identical mirror image of the other lever arm 51, so as to be able to activate the clamping elements 3a, 3a' of two clamping units 3, 3' simultaneously in one and the same working operation.

The scissors-like device 11, 11' has been duplicated for one and the same sleeper 2.

The chassis of the mobile unit M includes a guide 110 along which the bracket 54 can be moved in a direction corresponding to the longitudinal direction of the rail 4, through the medium of a sleeve or like element.

This enables the device 11 to be stationary in relation to the sleeper 2 during a clamping element releasing operation, as the mobile unit M moves slowly along the rails.

Although not shown, a spring or like device may be provided for an element 26' which functions to quickly move the stop device 20 down to a lowermost stopping and active position, prior to completion of a clamping element releasing movement.

Figures 6 and 7 illustrate a movable stop means 20.

Figure 6 shows the stop means in an out of the way, upwardly located position at a sufficiently insulated distance from a live rail 60.

The stop means or stop device 20 includes a protective plate 21 attached to the lower part 22a of an arm 22. The arm 22 is carried by two links, an upper link 23 and a lower link 24.

One end 23a of the upper link 23 is pivotally connected to the upper part 22b of the link 22. Its other end 23b is pivotally connected to the arm 51 and is moved reciprocatingly thereby. A plate 25 that includes an elongated groove 25a co- acts with a rod 26 and a spherical nut 26a.

The rod 26 is fixed to the chassis M through the medium of a spring element 27, and a thrust spring (not shown) may be placed over the rod section 26' so as to press the plate 25 constantly to the right in Figure 6.

The length of the rod 26 can be adjusted, by turning the rod.

The length of the arm 24 can also be adjusted by rotation.

When activating the lever 51 to release a clamping element, the link arrangement 26, 25, 23, 22 forces the plate 21 down to a lower position and there forms protection against the clamping element 3a flipping out of position.

When the release function has been completed, the lever 51 and the plate 21 return to the position shown in Figure 6.

It will be obvious to one skilled in this art that the arrangement comprising a rod 26, a plate 25 and an elongated grove 25a can be modified or replaced with an appropriate link arrangement or like means.

It will be understood that the invention is not restricted to the aforedescribed and illustrated exemplifying embodiment thereof, and that modifications can be made within the scope of the inventive concept as illustrated in the following Claims .

Claims

1. An arrangement for moving a clamping element, included in a clamping unit and movably fastened to a railroad sleeper, from a position in which said element fastens a rail to a railroad sleeper to a sleeper releasing position, wherein said clamping element is adapted for movement in a direction away from (and towards) said rail through the medium of support means belonging to said clamping unit and fixed in relation to said sleeper and with the aid of a device co-acting with said clamping element, wherein said device is adapted to move the clamping element away from said rail, characterised in that the arrangement includes a stop means which is separate from the clamping unit and which functions to prevent the clamping element from being moved by said device through a distance which, with an adapted distance, is greater than the distance required to release said element from said sleeper.

2. An arrangement according to Claim 1, characterised in that said stop means is fixed in relation to a mobile unit.

3. An arrangement according to Claim 1, characterised in that said stop means is movable and is adapted to take an ac- tive position solely, or generally solely, during movement of said clamping element to its releasing position.

4. An arrangement according to Claim 3, characterised in that one end-part of a lever arm has a hook-shaped recess or groove which functions as a stop means and which is adapted for co-action with an outer part of said clamping element.

5. An arrangement according to Claim 1 or 3, characterised in that said lever forms part of a link arrangement.

6. An arrangement according to Claim 1, characterised in that the clamping elements of at least two mutually opposing clamping units are adapted to be moved away from each other simultaneously.

7. An arrangement according to Claim 1, characterised in that said means is movable relative to a chassis, in a direction corresponding to the longitudinal extension of a rail in a railroad track.

8. An arrangement according to Claim 4, characterised in that one end-part of the lever carries a shoulder that can face towards the clamping element; and in that said shoulder is attached to one end of a two-arm lever arrangement and the other end is guided in a guide groove, by a link arrangement or the like.

9. An arrangement according to Claim 8, characterised in that one end-part of the lever arrangement is adapted to take a position close to a rail, or a position remote from said rail, or an upper or a lower position.