WO1998059113A1

WO1998059113A1 - A pressure plate adapted for an arrangement for a displacement of a clip-element to a holding position

Info

Publication number: WO1998059113A1
Application number: PCT/SE1998/001225
Authority: WO
Inventors: Lars Erne Holmberg; Jörgen RICKLUND; Stefan Ricklund; Per Olof Ohlsson
Original assignee: A. Rosenqvist Förvaltnings Ab
Priority date: 1997-06-23
Filing date: 1998-06-23
Publication date: 1998-12-30
Also published as: SE9702386D0; AU7950898A; SE9702386L

Abstract

The invention relates to an arrangement for bringing a clamping element, which is movably attached to a railroad sleeper and forms part of a clamp unit to a position in which it fastens a rail section to the sleeper. The clamping element can be moved in a direction towards and away from the rail section via support means belonging to the clamp unit and fixed in relation to the sleeper, with the aid of a device (50), in the form of a pressure plate, co-acting with the clamping element. A device (51) functions to aply to the sleeper a force (Fv) that acts towards the rail section prior to and/or upon commencement of the movement of the clamping element in said direction, so as to bring the sleeper (2) and the rail section (4) into mutual abutment. The device (51) thereafter functions to move the clamping element (3a) into clamping co-action with the rail section, in a known manner, while using a pressure plate with a groove (60).

Description

TITLE OF I^NVENTIO^N; _{A PRE}ssURE PLATE ADAPTED FOR AN ARRAN_GEMENT

FOR A DISPLACEMENT OF A CLIP-ELEMENT TO A HOLDING POSITION

FIELD OF INVENTION

The present invention relates to an arrangement acting as a pressure plate for bringing at least one clamping element to a fastening or clamping position, and more particularly to an arrangement by means of which at least one clamping element forming part of a clamp unit and movably fastened to a railroad sleeper can be brought to a position in which a railroad section is fastened to the sleeper.

The clamp unit used in the present invention includes a clamp- ing element which can be moved towards and away from said rail section via a support element belonging to said clamp unit and fixedly related to the sleeper, with the aid of a device co- acting with said clamping element or the like and holding a pressure plate.

More specifically, the invention encompasses the use of pairs of clamp units positioned on respective sides of a rail section and capable of being moved towards one another to a fastening position, in one and the same sequence or vice versa.

Even if the present invention mainly intends to provide an arrangement acting as a pressure plate, with the intention of bringing a clamping element to a fastening position, it shall be mentioned that said pressure plate also can be used to bring a clamping element from a fastening position to a releasing position.

BACKGROUND OF THE INVENTION

Several different types of arrangement for moving a clamping element fastened to a railroad sleeper and forming part of a clamp unit to a position in which a rail section is fastened to the sleeper are known to the art, and these are also using a pressure plate.

In this regard, the contents of U.S. Patent Publication US-A 3,690,264 and International Patent Publication WO 95/13427 (International Patent Application PCT/SE 94/01042) can be mentioned by way of example of prior art disclosures.

With respect to the characteristic features of the present invention, mention should also be made to a generally available and demonstrated arrangement which requires three separate working sequences to be carried out by means of three separate activatable devices in the form of hydraulically operated piston-cylinder arrangements, a first device for firmly clamping a railroad sleeper, a second device for lifting the firmly clamped sleeper into abutment with a rail section, and a third device for moving or displacing a clamping element to a fastening position.

This arrangement requires the sleeper to have exposed freely available end surfaces and is therefore restricted in practice to use when laying rail sections initially, and is also stationary relative to the sleeper as the three separate working sequences are carried out.

Such an arrangement is illustrated in Figure 1. The arrangement shown in Figure 1 will be more easily understood from Swedish Patent Application 9602434-4 "Machine for Mounting Fastener Elements to Rails", filed on June 19, 1996.

The content of patent publication US-A-4 494 463 is also a part of prior art.

The expedient pressure plates or pressure surfaces are here described as planar.

SUMMARY OF THE INVENTION

TECHNICAL PROBLEMS

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

When considering the present standpoint of techniques, as previously described, it will be seen that a technical problem is one of providing conditions, with the aid of simple means and measures with the pressure plates, which enable the bringing of a clamping element, belonging to a clamp unit, to a fastening position (or a releasing position) through a guide belonging to the pressure plate.

It is also a technical problem to realise the advantages pro- vided by forming this guide as a hook-shaped recess in the pressure plate. It is also a technical problem to be able to select suitable dimensions and a suitable shape for said recess.

Another technical problem is one of showing the use of a rub- ber and/or plastic covering that will be plastically deformed into said hook-shaped recess during the actuating sequence.

It is thereto a technical problem to chose material in the covering so that this will endure a relative movement between the pressure plate and the clamping element, and/or so that this will provide a possibility of a complete insertion of the clamping element, even if there are some mechanical obstructions.

When considering the present standpoint of techniques, and particularly when studying the arrangement described hereinafter with reference to Figure 1 and comprising three separately constructed and separately driven devices, to-wit a first device for firmly clamping the sleeper, a second device for raising the sleeper into abutment with an overlying rail section and, upon completion of this working sequence, functioning to activate a third device for at least initially moving the clamping element purely horizontally into co-action with said rail section, it will be seen that a technical problem is one of providing conditions, with the aid of simple means, which enable the functions of the three earlier known and mutually separate devices to be combined and performed by a single device, therewith providing a constructively simpler arrangement .

Another technical problem with an arrangement of this kind is to provide conditions which enable the sleeper to be lifted against the rail section without needing to utilise to this end frictional forces generated between planar, exposed end- surfaces of the sleeper and said first device, therewith enabling this function to be employed even when the railroad sleeper is embedded in a bed of gravel. Another technical problem is one of achieving the necessary lifting movement through hook-like co-action between the device or pressure plate and means belonging to the sleeper and fastened to the upper exposable surface thereof.

It will also be seen that another technical problem is one of realising the advantages that are associated with the use of sleeper-associated clamp units or clips as fastener means in order to totally or partly simplify the lifting of the sleeper.

Another technical problem is one of realising the advantages that are afforded when using parts of the clamping element that lies distal from the rail section as a fastener surfaces for the pressure plate for the lifting movement.

It will also be seen that a technical problem is one of providing, with the aid of simple means, conditions whereby a rail section can be firmly placed on underlying sleepers while moving along the rail section.

Another technical problem is one of providing an arrangement which will enable railroad sleepers to be secured firmly to parallel rail sections more quickly than was earlier the case.

Another technical problem is one of realising the significance of and the advantages obtained when said one device, or pressure plate, is adapted to exert on the sleeper, via chosen clamping elements, force components that acts vertically and horizontally on said rail sections prior to and/or upon initial displacement of the clamping element in said direction towards its co-action with the rail section, therewith to bring the sleeper and the rail sections into mutual abutment through the vertical force component.

It will also be seen that a technical problem is one of realising the conditions for and advantages associated with the use of all sleeper-associated clamp units with its four clamping elements for lifting the sleeper, when necessary.

Another technical problem is one of realising the significance of allowing adapted horizontally acting forces to engender conditions that enable the clamp units, through the clamping elements, to apply force components that act vertically upwards, in conjunction with particular constructive measures.

Another technical problem is one of realising the significance of and the advantages that are obtained when allowing said single device, or pressure plate, to displace respective clamping elements into clamping co-action with the rail section, in a known manner.

Another technical problem is one of realising the significance of and the structural measures required by allowing said vertical force components to be adapted for compressing a resilient pad placed between the sleeper and the rail section, through the medium of said clamp units and particularly the clamping elements included in said units .

When said single device, and thereto belonging pressure plate, is comprised of a two-arm lever arrangement with one end-part of respective lever arm capable of co-acting with said clamping element or the like, by means of its pressure plate, and with the other end of said lever arm capable of co-acting with an hydraulic or pneumatic piston-cylinder arrangement with the rotational axis of said lever arm arrangement being orientated over said clamp unit, it will be seen that a technical problem is one of realising the significance of and the advantages afforded by positioning the rotational axle at a horizontally equal or greater distance from the rail section, in a direction away from the rail section, than the outer surface parts of said clamping element, that co-acts with said device or pressure plate, when the clamping element of the clamp unit is in a releasing position. It will also be seen that a technical problem resides in realising the significance of and the advantages afforded by providing one end-part of the lever arrangement with a hook- shaped recess in the pressure plate adapted for co-action with the curved outer surface part of the clamping element.

It will also be seen that a technical problem resides in realising the significance of enabling the clamping elements of at least in pairs and usually four mutually opposition clamp units to be moved simultaneously to a fastening position in which parallel rail sections are fastened to one and the same railroad sleeper.

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 kind described in the introduction and shows specifically that a pressure plate, adapted for a displacement of a clamping element, is to be formed with a recess adapted for co-action with one or several outer surface parts of said clamping element.

As proposed embodiment, falling within the scope of the present invention, it is proposed that said recess is to constitute a straight, horizontally oriented, groove.

It is further proposed that the cross section of said groove should have a surface corresponding to a part of a cylindrical surface.

As an alternative it is possible that the cross section of said groove is given at least one, obliquely oriented, surface.

It is specifically proposed that the most open part of said groove has an opening which is adapted to be equal to, or somewhat larger than, the diameter of the clamping element. It is further indicated that said recess is totally or partly surfaced with a rubber and/or plastic covering, and that an elastic impression of the clamping element into the covering forms a hook-shaped recess.

In this case it is proposed that a part of the rubber and/or plastic covering is to be selected with expediently adapted material properties regarding hardness.

The part of the covering can be adapted to extend over an obstruction belonging to the clamp unit or the sleeper.

As an alternative it is proposed that said part is to co-act with a second part, a subjacent part of a rubber and/or plastic covering, selected with expediently adapted material properties regarding softness .

The distance between upper and lower surfaces, converging to- wards the inner part of the recess, are to be adapted so that these can form bearing surfaces towards actuating surfaces belonging to the clamping element, it may be suitable to support the actuating surfaces of the clamping element towards a lower surface and an inner surface.

APVftNTAgES

Those advantages primarily characteristic of an inventive arrangement reside in the provision of conditions which, through simple means in the form of a pressure plate that can act upon a clamping element, enable a controllable movement of a clamping element into a clamp unit (fastening position) or a controllable movement of a clamping element out of a clamp unit (releasing position).

Thereto it is shown the possibility for a railroad sleeper to be lifted into abutment with an adjacent rail section with the aid of one single device and thereto belonging pressure plate, by applying to the clamping elements force components that acts vertically and horizontally towards the rail sections and thereafter moving the clamping element through the horizontal force component into co-action with and attachment to said rail section.

The inventive arrangement enables each of the functions of firmly clamping and securing the railroad sleeper, of lifting the sleeper into abutment with a rail section and/or of moving a clamping element into a fastening position to be carried out with the aid of one single piston-cylinder arrangement and the particular mechanical construction of devices required here- for.

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

The present invention will now be described in more detail with reference to exemplifying embodiments thereof and also with reference to the accompanying drawings, in which

Figure 1 is a perspective view of a known arrangement that includes a first device intended for firmly clamping a railroad sleeper having exposed end-surfaces, a second device which functions to lift a freely positioned railroad sleeper into abutment with an adjacent rail section, and a third device which functions to move a clamping element of a clamp unit horizontally towards said rail section; Figure 2 is a perspective view of a mobile unit which can be moved along two parallel rail sections, wherewith the mobile unit is provided on one side with an inventive arrangement for securing railroad sleepers to rail sections, and also two release arrangements;

Figure 3 is a perspective view of a clamp unit and shows a clamping element in a "releasing" position;

Figure 4 is a perspective view of the clamp unit in Figure 3, and shows the clamp unit moved to a "fastening" position;

Figure 5 is a side view showing the clamping element in the fastened position of Figure 4 in full lines and indicating in broken lines the position of the clamping element in Figure 3 prior to said element being moved against the rail section by the inven- tive device and pressure plate;

Figure 6 is a side view of the fastening arrangement shown in Figure 2, and shows its attachment to the mobile unit;

Figure 7 is a side view of one part of two co-acting parts in an orientation adapted for a position in which the clamping element may be in a releasing position, and shows two clamping elements in a fastening position relative to the rail section;

Figure 8 illustrates in perspective a state in which each arm has brought its respective clamping element to a fastening position with an intermediate rail section; Figure 9 is a movement diagram significant of the arrangement shown in Figures 6, 7 and 8, in accordance with the invention;

Figure 10 is a side view of an alternative embodiment of an arrangement, and shows said arrangement in two different positions (A and B);

Figure 11 is a side view of an alternative fastening ar- rangement having a movable attachment to the mobile unit;

Figure 12 is a sectional view of a guide and a sleeve included in the movable attachment of Figure 11;

Figure 13 is a perspective view of an alternative embodiment with a device in the form of a pressure plate with the form of an equally sided parallel trapezium;

Figure 14 is a cross sectional side view of the form of a recess shown in Figure 13 in co-action with a clamping element; and

Figure 15 is yet another alternative embodiment where a re- cess is formed by an impression of the clamping element in a rubber and/or plastic covering.

DESCRIPTION OF A PRIOR ART ARRANGEMENT

Figure 1 shows in perspective an arrangement 1 by means of which a clamping element 3a included in a clamp 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.

The clamping element 3a can be moved towards and away from the rail section 4 via support means belonging to the clamp unit and affixed to the sleeper 2 and with the aid of a device that, as a pressure plate, can co-act with the clamping element.

The clamp unit 3 and its associated clamping element 3a and support means will be described in more detail hereinafter with reference to Figures 3, 4 and 5.

The arrangement shown in Figure 1 includes three different devices on one side of the rail section 4, for performing three separate operations.

The functions performed by these three devices are co-ordinated with the functions of corresponding devices on the other side, not shown in Figure 1.

A first device 5 is adapted to firmly clamp a railroad sleeper 2 via end-related exposed opposite planar surfaces, where the illustrated planar surface 2a is caused to co-act frictionally with a planar surface 5a' on the device 5 and through corre- sponding, opposing co-action between the surface of the sleeper and a planar surface on said device, these latter surfaces not being shown in Figure 1.

A second device 6 ( and a corresponding device adj acent the rail section 4') is adapted to raise or lift the sleeper 2 into abutment with a pair of overlying rail sections 4, 4'.

A third device 8 is adapted to move a clamping element into a fastening position against the rail sections 4, 4'.

More specifically, the first device 5 is comprised of a first lever arm related arrangement with opposing clamping plates, of which one is referenced 5a, facing towards one of the opposing end surfaces of the sleeper 2, which is referenced 2a, wherein the clamping plates can be manoeuvred into clamping co-action with the sleeper 2 with the aid of side-related piston-cylinder arrangements, of which one is referenced 5b in Figure 1. The illustrated two-arm lever arrangement utilises? a horizontal pivot axle 5b, and a corresponding axle is located on the other side .

The embodiment illustrated in Figure 1 also includes two other side-related devices, of which one is referenced 6. These devices have the form of an hydraulic or a pneumatic piston-cylinder arrangement adapted to lift a sleeper 2 firmly clamped by the first devices 5, 5' into abutment with two overlying rail sections 4, 4'.

The arrangement illustrated in Figure 1 also includes two third devices, of which one is referenced 8. These third de- vices also utilise a two-arm lever system where a support surface 8a at the one end-part of the arm is able to co-act with the clamping element 3a of the clamp unit 3, whereas the other end-part is caused to rotate about an axle 8c, by means of a piston-cylinder arrangement 8b.

Activation of the devices 5, 5' causes the surface 5a to be brought into clamping co-action with the surface 2a on one side, while a corresponding surface on similar devices is caused to be brought into co-action with an opposing end-sur- face of the sleeper 2.

The piston-cylinder 6 is then activated to raise the sleeper 2 into abutment with the rail sections 4, 4'. When this working process has been completed, the third device 8 is activated to fasten the clamping element to the rail sections.

DESCRIPTION OF EMBODIMENTS AT PRESENT PREFERRED

Shown in Figure 2 is a perspective view of a four-wheel mobile unit "M" which can be moved along parallel rail sections 4, 4', in accordance with the present invention. In the illustrated case, the mobile unit can be moved with the aid of a loading machine 9 and an arm 9a belonging thereto.

The mobile unit M has a chassis to which there is attached a fastener device 10 significant of the invention, and also two release devices 11.

The inventive arrangement includes four fastening clamp units which are co-ordinated two and two for co-action with opposing edge-parts of a track-forming rail section 4 and a track-forming rail section 4 ' .

Alternatively, movement of all clamp units can be co-ordinated through the medium of a fastening device or by pairs of clamp units.

For the sake of simplicity, the following description will be made initially with reference solely to one clamp unit.

Since the present invention mainly includes the fastening device 10, only this device will be described in more detail hereinafter.

The fastening device 10 comprises a scissors-like means adapted for co-action with the rail section 4 and a scissors- like means adapted for co-action with the rail section 4 ' , said scissors-like means having mutually the same construction and being co-ordinated with one another.

The two scissors-like means enable the clamping elements of four clamp units to be moved simultaneously to a fastening position.

A scissors-like means can be actuated by a single piston-cyl- inder arrangement.

The fundamental principles of the present invention will be exemplified hereinafter with reference as to how a lifting force through a pressure plate can actuate a clamping element, and how a clamping element can be moved to a fastening position.

It will be obvious to a person skilled in this art how this principle can be duplicated with scissors-like means and how two scissors-like means can be made to co-act to firmly fasten four clamping elements, two elements for one rail section 4 and two elements for the other rail section 4 ' , in one and the same working operation.

In accordance with one embodiment of the invention, four clamping elements are moved to a fastening position simultaneously, two for each rail section, with the aid of a respective piston-cylinder arrangement, although the working operation could be carried out with the aid of a single piston-cylinder arrangement, subject to minor modifications in construction.

Figures 3 and 4 are perspective views of a clamp unit 3 used in conjunction with the invention.

Although Figures 3 and 4 show only one clamp unit 3 active on the right side of the rail section, it will be understood that two clamp units may be used in practice, one on each side of said rail section.

Figure 3 shows a clamping element 3a in a "releasing" position, while Figure 4 shows the clamping element 3a in a for- wardly displaced and "fastening" position.

The clamp unit 3 is comprised of a springy clamping element 3a which is made of steel and placed in a groove or channel in a plastic element 3b.

The plastic element 3b, and the clamping element 3a, is dis- placeably mounted in a holder or support means fastened to the upper surface 2b of the sleeper 2. The clamp unit also includes a plastic element 3c that functions as a side-insulator.

Figure 3 shows the clamping element 3a and the plastic element 3b in a non-clamping or "releasing" position, with the rail section 4 placed loosely on a resilient pad 3e that rests on the upper sleeper surface 2b.

Figure 4 shows the clamping element 3e in a rail-section fas- tening position, in which the clamping element 3a with the plastic element 3b co-acting with an upper surface part 4a of the bottom flange of the rail section 4.

When there is a need to lift the sleeper up against the mutu- ally parallel rail sections 4, 4', the inventive arrangement enables the sleeper to be clamped firmly through the medium of at least two clamp units and the sleeper lifted by applying upwardly acting forces on the clamp units and by displacing the clamping elements 3a and the plastic elements 3b from the position shown in Figure 3 to the position shown in Figure 4 with the aid of one single device, formed as a pressure plate 50.

The expression "one single device" shall be interpreted as meaning that the necessary three working sequences can be performed through the medium of single co-action between said device and said clamping element or the like as the device moves in accordance with its movement plan or pattern.

Figure 5 shows a significant part 50 of the device, said part consisting of a lower part 51a, formed as a pressure plate, of an arm 51.

The invention is based on a particular configuration of the lower arm-part or pressure plate 51a and a particular pattern of movement of said lower arm-part. The lower arm-part 51a shall be movable towards and into abutment with a curved outer surface part or surface 3g of the clamping element 3a, by means of mechanical and/or hydraulic/pneumatic arrangement.

When an adapted, horizontally acting pressure is applied to the surface 3g, the lowermost part 51a of the arm 51 will be raised so that the sleeper 2 will be lifted up to and against the overlying rail section 4 as a result of this co-action be- tween said surface 3g and said arm-part 51a.

In order to achieve this clamping co-action it is necessary that, according to Figure 8, the lowermost part 51a' of another arm 51 ' also is raised slightly so as to bring the sleeper 2 into abutment with respective overlying rail sections 4.

The clamp units shall be positioned opposite one another and at the end-parts of the sleeper 2.

In this raised position of the sleeper, the clamping element 3a shall be moved to the position shown in Figure 4 by the arm-part 51a, at the same time as an opposing clamping element 3a ' is moved to a fastening position by its corresponding arm- part 51a.

According to one preferred embodiment, four such clamping elements associated with one and the same railroad sleeper 2 are moved to a fastening position simultaneously.

The bottom part 51a of the arm 51 of the device 50 now functions to apply to the sleeper 2 a force component that acts vertically towards the rail section 4 prior to and/or upon initial movement of the clamping element 3a horizontally to- wards said rail section 4, i.e. the sleeper 2 is lifted directly or indirectly to a position in which the clamping element 3a can take the position shown in Figure 4, with the aid of said clamp units 3. Application of this vertical force component brings the sleeper 2 and the parallel rail sections 4, 4' into abutment with one another. It is only when this state is reached that the device 50 moves clamping elements 3a into clamping engagement with the rail sections 4, 4'.

The vertically, but also horizontally, acting force components are conveniently adapted to slightly compress a resilient pad 3e placed between the sleeve 2 and the rail section 4.

In the embodiment shown in Figures 6 and 7, the device 50 is comprised of a two-arm lever arrangement where one end-part 51a' of the lever arm 51' can co-act with the outer surface part 3g ' or the like of the clamping element 3a¹, and the other end-part 51b' of the lever arm co-acts with an hydraulic or a pneumatic piston-cylinder arrangement 52.

The rotational axle 53' of the lever arm 51' is positioned above said clamp unit 3 ' .

The rotational axle 53' carries bearing means for the arm 51' and is attached to a bracket 54. The bracket, in turn, is fastened to the chassis of the mobile unit M with bolts 55, 55a, such as to allow adjustments to the arrangement 50 to be made through the medium of inserts 56 placed between the bracket 54 and a chassis fastener device or fastener rail 57.

As will be evident from Figure 7, when the clamping element 3a ' of the clamp unit 3 is in its non-engaging position shown in Figure 3, the axle 53' is located at a greater horizontal distance "a" from the rail section 4, in a direction away from the rail section 4, than said outer surface part 3g' of the clamping element 3a'.

can in the practical application be selected as smaller than what is shown, and even approach zero. The distance "a" can even be selected as being negative depending on the form of the groove 60 in the pressure plate 51a.

The bottom-most part 51a' of the arm 51' will therewith move in a arcuate path with one horizontal and one vertical force component Fh and Fv, that acts to lift the sleeper 2 via the clamp unit 3 ' , while continued rotary movement about the axle 53' urges the clamping element 3a' to the position shown in Figure 7.

One end-part 51a' of the lever arm includes a hook-shaped recess 60 (part cylindrical in shape), adapted for co-action with the circle-arcuate outer surface part 3g ' of the clamping element .

As will be seen particularly from Figure 8, the lever arms 51 and 51' are part of a scissors-like device with the lever arms 51' and 51 being mutually identical and in mirror-image relationship, so as to be able to actuate two clamp units 3, 3' and their respective clamping elements 3a, 3a' simultaneously in one and the same working operation.

The scissors-like device 50 is duplicated for one and the same railroad sleeper 2.

According to a further embodiment of the invention, the lever arm 51 may alternatively be included in a link arrangement according to Figure 10.

As shown in Figure 8, the scissors-like device 50 may include a two-arm lever system in which the two arms are swung to a position in which the mutually opposing clamping elements of respective clamp units 3, 3' are located in a final fastening position.

Figure 9 is intended to illustrate principally the arcuate movement of the arm 51 (or the arm 51') between a position in which the free end 51a of the arm strikes against the outer surface part 3g of the clamping element 3a and in which the clamping element 3a has been moved to its fastening position.

According to Figure 9, the arcuate movement of the arm 51 shall commence at an adapted distance "b" from a vertical line 91 that passes through the centre 92 of the arcuate path and terminates at the reference "C" .

This arcuate movement generates a force on the outer surface part 3g of the clamping element 3a that can be divided into a horizontal force component Fh and a vertical force component Fv, where force component Fv shall primarily serve to lift the sleeper 2 towards and against the rail section 4 when necessary.

The clamping element 3a is then moved horizontally by the horizontally acting force component Fh, where the vertically acting force component Fv serves to allow the free end 51a of the arm 51 to slide along the surface 3g.

Figure 10 illustrates an embodiment of a link arrangement in which an arm 100 co-acts with an arm 103 through the medium of two links 101 and 102 (the arm 103 corresponding to the arm 51 in Figures 5, 6 and 7), wherein the bottom 103a of the arm 103 includes a groove or recess 104 which is located beneath a contemplated lowest position of the surface 3g.

When a surface 105 strikes against the surface 3g as a result of the arcuate movement of the arm 100 or some other movement to the left, the arm 103 will be lifted through the medium of the links 101 and 102 and immediately when the groove or recess 104 is engaged with the surface 3g, lifting of the sleeper 2 commences, if necessary, and displacement is effected towards the fastening position of the clamping element, in accordance with the aforedescribed sequence.

The recess 60 and the recess 104 may both conveniently include a bottom lip whose length exceeds the radius of the clamping element 3a, such as to provide a horizontal support surface for the lifting movement.

It will be understood that the arrangement may include force- limiting means that will prevent vertical and/or horizontal overloading of the clamp units.

Figure 11 is a side view of an alternative fastening arrangement that includes a movable attachment to the mobile unit M. Figure 12 is a sectional view of a guide and a sleeve for the movable attachment shown in Figure 11.

As will be seen, there is attached to the mobile unit M a guide 110 along which the bracket 54 can be moved in a direc- tion corresponding to the longitudinal direction of the rail section 4, through the medium of a sleeve 111 or like device.

The device 50 can herewith be kept stationary relative to the sleeper 2 during the fastening operation, while moving the mo- bile unit M slowly along the rail sections.

Although not shown, springs or like devices may be provided for returning the device 50 quickly to a starting position upon completion of a fastening function.

The invention is based upon being able to control the movement of the clamping element 3a in and out of the clamp unit 3.

Figure 8 has in this respect shown that that a pressure plate (51a') is formed with a recess 60' adapted for co-action with one or several outer surface parts of a clamping element 3a.

It is here shown that said recess 60 constitutes a straight, horizontally oriented, groove with a cross section that has a surface corresponding to a part of a cylindrical surface.

A decreased radius of curvature for the recess 60 below the radius of curvature for the clamping element 3a provides the advantage of that discrete point-formed contact surfaces 61, 62 are formed with a high contact pressure, and thereby a safe movement even under hard circumstances.

There is nothing that prevents that the radius of curvature for the recess 60 is increased to be somewhat larger than the radius of curvature for the clamping element 3a in order to provide a larger catching area in the beginning of the co-action.

The selected angle of contact is shown in Figure 5 and should be given a value smaller than 170° and larger than 120°.

Figure 13 shows, in perspective view, the lower part of a pressure plate 51a and Figure 14 a cross sectional view of a recess 60.

The recess is here shown as a groove with a cross section that has at least one obliquely oriented upper surface 60a, a ver- tical support surface 60c, and a catching and lower support surface 60b.

According to this embodiment the groove has two inwardly converging surfaces 60a, 60b, with one connecting support surface 60c in the back, giving the groove the form of an equally sided parallel trapezium.

The surfaces 60a, 60b is to form an angle in relation to the connecting surface 60c of 105° to 170°, and are not necessar- ily equal.

These surfaces 60a and 60b could co-act with the clamping element 3a as discrete point-formed contact surfaces as shown in Figure 5.

Smaller angular values may then give a higher surface pressure but may also require a deeper groove. Figure 14 is intended to illustrate that the most open part of the groove 60 can have an opening which is adapted to be equal to or somewhat larger than the diameter of the clamping element 3a, and that the clamping element 3a rests towards the surfaces 60a and 60b.

Figure 15 is intended to illustrate that the recess 60 can be totally or partly surfaced with a rubber and/or plastic covering 64, and that an impression of the clamping element 3a into the covering 64 will form a hook-shaped recess 60, which prohibits a vertical movement.

An upper part 64a of the rubber and/or plastic covering 64 is selected with expediently adapted material properties regard- ing hardness.

It is specifically shown that said part 64a is positioned and dimensioned to extend over an obstruction ( 63 in Figure 5 ) belonging to the clamp unit.

As a possible alternative embodiment it is shown that said part 64a can co-act with a second part 64b, a subjacent part of a rubber and/or plastic covering, selected with expediently adapted material properties regarding softness.

Said obstruction 63 has a very limited extension perpendicularly to what is shown in Figure 5.

The distance between upper and lower surfaces 60a, 60b, con- verging towards the inner part of the recess 60 or towards the surface 60c, is adapted so that these can form bearing surfaces towards selected actuating surfaces belonging to the clamping element .

The recess 60 is here shown in a position where a clamping element 3a is to be moved to a fastening position. To move a clamping element from a fastening position to a releasing position it is proposed that the pressure plate 51a is turned so that the recess 60 can co-act with inner surface parts belonging to the clamping element 3a.

In Figure 14 a lower edge 65 beneath the oblique surface 60b has been given a height of 2 to 5 mm and the depth of the recess 60 is selected to be 7 to 12 mm, such as approximately 10 mm.

There is nothing that prevents the elongated extension of the groove 60 to be somewhat angular in its form according to line 66, as shown in Figure 13, even if the recess 60 has been shown as a straight groove in the previous description.

The width of the recess 60 is to be adapted so that it can agree with the different forms of the outer surface part 3g of the clamping element 3a in a fastening position and in a releasing position.

Even though the embodiments previously described shows an inwardly upwardly directed movement of the pressure plate 51a for it to be able to lift the railroad sleeper and the clamping element 3a to the rail section 4 before the clamping element 3a is moved to a fastening position it is obvious that this technical effect can be achieved also with a purely horizontal movement for the pressure plate 51 towards the rail section 4 if an underlying lip, formed by the surfaces 60b and 65, dimensioned to first, if required, lift the clamping ele- ment 3a and the sleeper towards the rail section at a purely horizontal movement and thereafter, as the clamping element 3a is caught in the pressure plate 51a, move the clamping element to a fastening position.

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 defined in the following Claims.

Claims

1. An arrangement for moving a clamping element which is movably fastened to a railroad sleeper and forms part of a clamp unit to a position in which a rail section is fastened to said sleeper or vice versa, wherein the clamping element can be moved towards and away from said rail section via support means belonging to said clamp unit and can be fixedly related to the sleeper, with the aid of a device, in the form of a pressure plate co-acting with said clamping element, characterised in that said pressure plate (51a) is formed with a recess (60) adapted for co-action with one or several outer surface parts of a clamping element (3a).

2. An arrangement according to Claim 1, characterised in that said recess constitutes a horizontally oriented groove.

3. An arrangement according to Claim 1 or 2, characterised in that the cross section of said groove has a surface corre- sponding to a part of a cylindrical surface.

4. An arrangement according to Claim 1 or 2, characterised in that the cross section of said recess has at least one obliquely oriented surface.

5. An arrangement according to Claim 2, 3 or 4, characterised in that the most open part of said groove has an opening which is adapted to be equal to somewhat larger than the diameter of the clamping element .

6. An arrangement according to Claim 1, characterised in that said recess is totally or partly surfaced with a rubber and/or plastic covering, and that an impression of the clamping element into the covering forms a hook-shaped recess.

7. An arrangement according to Claim 6, characterised in that a part of the rubber and/or plastic covering is selected with expediently adapted material properties regarding hardness.

8. An arrangement according to Claim 7, characterised in that said part is adapted to extend over an obstruction belonging to said clamp unit.

9. An arrangement according to Claim 7, characterised in that said part co-acts with a second part, a subjacent part of a rubber and/or plastic covering, selected with expediently adapted material properties regarding softness.

10. An arrangement according to Claim 1, characterised in that the distance between upper and lower surfaces, converging towards the inner part of the recess, is adapted so that these can form bearing surfaces towards actuating surfaces belonging to the clamping element.

11. An arrangement according to Claim 1, characterised in that said device, formed as a pressure plate, is adapted for applying to the sleeper a force that acts towards the rail section such as to bring the sleeper and said rail section into mutual abutment, either prior to and/or upon commencement of the movement of said clamping element in said direction; wherein said device thereafter functions to move the clamping element into clamping co-action with said rail section.

12. An arrangement according to Claim 11, characterised in that said force is adapted so as to slightly compress a resilient pad placed between the sleeper and the rail section.

13. An arrangement according to Claim 11, characterised in that said device (50, 60) is a doubled two-arm lever arrangement, that respective one end-part (51a) of the lever arm can co-act with said clamping element or the like, that respective other end-part of said lever arm co-acts with an hydraulic or a pneumatic piston-cylinder arrangement (52), that the pivot axle ( 53 ) of respective lever arm is positioned above said clamp unit, that in a non-engaging or "releasing" position of the clamping element (3a') of said clamp unit (3') the pivot axle ( 53 ' ) is located at a horizontally equal or greater distance from the rail section, in a direction away from the rail section, than said outer surface part (3g') of the clamping element, adapted for co-action with said device.

14. An arrangement according to Claim 13, characterised in that one end-part of respective lever arm includes a hook-shaped recess ( 60 ' ) adapted for co-action with the outer surface part (3g') of said clamping element.

15. An arrangement according to Claim 11 or 13, characterised in that respective lever arm forms part of a link arrangement.

16. An arrangement according to Claim 11, characterised in that the clamping elements of at least two mutually opposing clamp units are adapted for simultaneous movement towards one another.

17. An arrangement according to Claim 11, characterised in that said force is adapted to be able to act on four railroad sleeper clamp units simultaneously.

18. An arrangement according to Claim 11, characterised in that said as a pressure plate acting device is movable relative to a chassis, in a direction corresponding to the longitudinal extension of a rail section (4).

19. An arrangement for moving a clamping element which is movably fastened to a railroad sleeper and forms part of a clamp unit to a releasing position by means of a movable device, characterised in that said clamping element (3a) is adapted to be moved from a fastening position ( Figure 8 ) by a planed device, which presents a recess (60, 60') adapted to a co-action with a surface part belonging to the clamping element (3a).

20. An arrangement according to Claim 19, characterised in that said recess (60) constitutes a horizontally oriented groove, positioned in the lower part of the device.

21. An arrangement according to Claim 19 or 20, characterised in that said device and said recess ( 60 ) given a horizontal length that exceeds the corresponding length of the clamping unit ( 3 ) .