HK1147117B - Connection element for running rails and running rail system - Google Patents

Description

Connecting element for a running rail and running rail system

Technical Field

The invention relates to a connecting element for a running rail/carriageway (laufschien) of a suspended rail, having a cavity for receiving the running rail and a fastening device for preventing the running rail from being pulled out of the cavity; the invention also relates to a running rail system with a plurality of running rails that can be connected by means of said connecting element.

Background

Such a connection comes from DE 4317498a 1. The suspension rail described in this document is mainly made of a U-profile, the branch ends of which are bent towards each other to form a running surface, leaving an intermediate through-channel. In order to connect the two running rails to one another at their ends, connectors are used which have substantially the same cross section as the running rails but which engage them in a wrap-around manner. A fixed, secure connection preventing undesired extraction or removal of the connected running rails is achieved in that the ends of the running rails have holes which are aligned with the holes in the connector. Mechanical bolts are then threaded through the aligned holes and prevent the running rail from slipping or being withdrawn. Although this connection method establishes a reliable connection, installation costs are high. The holes in the running rail must be aligned with the holes in the connector and then the machine bolts are screwed in with a tool. Although these bolts can be screwed in beforehand during the manufacture of the connector, there is a risk that during the transport of the connector: the protruding bolt is dropped or damaged by hitting it or the threads of the hole or bolt. Additionally, tools must be carried at all times to tighten the bolts.

It is also possible for the connection means to have a mechanical bolt which is screwed onto the C-shaped guide rail in a blind hole or with a nut. That is to say in this case the guide rail does not have a hole for the connector bolt to engage. The C-shaped rail is only clamped here. A disadvantage is that, when the screw is tightened too firmly, the limbs of the C-shaped guide rail are bent too strongly inward, so that the travel space for the carriage guided therein is too small and the carriage can get stuck therein. When the screw is not tightened sufficiently, the connection may loosen during operation. Here again tools are required to create the connection.

In order to achieve a tool-less connection of the running rail, WO 2007/068897a1 proposes another connector and another running rail system. In this document, the end of the running rail has a projection in the longitudinal direction, which is cut off by a notch immediately before its end. The running rail is pushed into a connector with a corresponding cross section. Cutouts are provided in the connector corresponding to these indentations, through which the two webs of the insert can pass to establish the connection. The insert has a spring web which substantially matches the shape of the connector and which rests against the outer side of the connector. When the insert is fully inserted into the connector and into the running rail through the indentation, the resilient tab of the insert snaps into the outer contour of the connector to prevent the insert from falling out. Although this allows a tool-free assembly of the running rail system, it has the disadvantage that, in addition to the connector, a further insert is required, which has to be adapted to the shape of the connector as exactly as possible. Furthermore, when the running rail system is installed, the recess in the running rail must exactly correspond to the cutout of the connector, so that the tab of the insert can be inserted not only through the cutout of the connector but also through the recess in the running rail.

WO 2005/089691 relates to a locking coupling for two guide rails of a suspended track. First and second couplers are provided on the ends of the two rails, respectively, and engage each other when the two rails are aligned with each other. Each of the links has a hinged latch, the first link having a latch member with an angled end which is engageable with a pin projecting out of the latch of the second link, wherein the latch member is arranged to engage into an indentation of the latch, wherein both latches are activated by moving the latch member. The disadvantage is that a reliable, fixed and releasable connection of the two rails can only be achieved with complex, expensive and costly latching couplings.

DE 2741096a1 relates to a guide rail device, in particular for a two-rail suspended rail vehicle for transporting persons, which essentially comprises a box-shaped track carrier arranged with an expansion joint in its longitudinal extension, which has a running rail for supporting wheels or guide rollers of a chassis running in the carrier, wherein the track carrier has a cutout for a suspension connecting the chassis to a vehicle body to pass through. In order to bridge the telescopic joints arranged between the lane carriages in a manner which is as simple and space-saving as possible, wherein the bridging should automatically and steplessly compensate for changes in the length of the carriages, the telescopic joints between the two lane carriages are bridged in the region of the running track for the supporting wheels or guide rollers by means of a triangular filler piece which is respectively mounted in the running track and which rests with its inclined face against a corresponding inclined face formed by the lane carriage under the action of a spring force.

DE 3343075C2 relates to a rail-mounted suspension rail, in particular a monorail suspension rail, comprising a suspendable profile rail with a suspension fastening device and a running vehicle, wherein the profile rail comprises an elongated hollow body and a continuous longitudinal slot for receiving the suspension fastening device. The suspension fastening device comprises a metal sheet with a lead-in tip with a subsequent connected barb projecting laterally out of the plane of the metal sheet, both arranged in a T-shaped, elongated hollow body serving as a profile running rail, wherein the barb engages with connecting plates arranged laterally of the continuous longitudinal cut on the end side of the "T" bar of the profile running rail. The mounting of the profile rail on the top-side fixed suspension fastening is effected only by introducing the lead-in tip of the suspension fastening into the longitudinal slit of the profile rail and additionally pushing the profile rail upwards, wherein the two sides of the "T" bar are inclined outwards, slide over the outer surfaces of the barbs and can then be snapped together again in order to engage the webs with the barbs. In this case, the insertion point cannot be simply pulled out of the longitudinal slot of the profile running rail again.

Disclosure of Invention

The object of the present invention is therefore to provide a connecting element or running rail system of the type mentioned in the introduction, which overcomes the disadvantages mentioned above and, while reliably connecting the running rails of the running rail system, enables a particularly simple, quick and tool-free installation.

The object of the invention is achieved by a connecting element as described below and a running rail system as described below.

The invention provides that the fastening device of the connecting element has at least one spring-elastic first connecting claw which, in the relaxed state, projects obliquely into the cavity in the insertion direction of a first running rail. This advantageously establishes a secure connection of the running rail to the connecting element without additional loosening elements or tools, since the connection can be established solely by the connecting element itself. A quick and simple mounting of the running rail system is thus simultaneously achieved.

In a preferred embodiment, a reliable connection is ensured in the following manner: the at least one connecting claw is formed to be pressed out of the cavity by the running rail from a relaxed state when the running rail is pushed in, and to be resiliently embedded in the first running rail when the first running rail is withdrawn. The insertion is effected at the time of extraction in the following manner: the coupling pawl rests elastically against the pushed-in running rail and pulls counter to its inclined position when pulled out. The stronger the pulling, the tighter the connection claw rests against the running rail and the connection claw penetrates into the running rail more strongly. Above a certain tension, however, the running rail can be pulled out of the connecting element again. The tension is determined such that the running rail cannot be withdrawn in normal use.

In one embodiment of the invention, it is advantageously provided that the connecting claw has a spring-elastic tongue which projects obliquely inward into the cavity in the insertion direction. The spring-elastic tongues ensure that the coupling claws can be pressed out of the cavities when they are pushed into the running rail and, when they are tensioned, abut against the pushed-in running rail.

In order to ensure a secure connection between the connecting element and the running rail, the front end of the connecting claw projecting into the cavity can be designed as a structure for poking into the running rail, wherein, in an embodiment which is advantageous in terms of production, this structure can be designed as a cutting edge or as a tip. In order to ensure improved penetration of the structure for penetrating the running rail when the running rail is pulled out, the structure for penetrating can be bent in the direction of the running rail to be pushed into the cavity.

In order to connect the two running rails in a simple and rapid manner, in an advantageous embodiment of the invention, a spring-elastic second connecting claw is provided, which corresponds to the first connecting claw and which projects into the cavity in the relaxed state at an angle in the insertion direction of the second running rail. This embodiment is particularly advantageous for connecting pieces in which the running rails are pushed in from opposite push-in directions to one another.

In order to simplify the insertion and thus the installation of the running rail system, a first insertion limiting lug which is elastic in terms of a spring and which is arranged on the connecting piece for limiting the insertion of the first running rail in its insertion direction into the cavity provided for it can advantageously be provided on the connecting piece, which first insertion limiting lug projects into a further cavity provided for the second running rail. The insertion stop web may preferably have a stop edge which extends in a plane perpendicular to the insertion direction of the first running rail.

Advantageously, the first insertion stop tab can project obliquely into a cavity provided for the second running rail in the relaxed state and is configured to be pressed out of the cavity by the second running rail when the second running rail is inserted. In particular, in embodiments in which the insertion directions are opposite to one another, it is advantageous if, in order to limit the insertion of the second running rail into the cavity in its insertion direction, a second spring-elastic insertion-limiting lug is provided on the connecting part, which second insertion-limiting lug, in the relaxed state, projects obliquely into the cavity provided for the first running rail and is configured to be pushed out of the cavity by the first running rail when the first running rail is inserted into the cavity. The insertion stop web preferably projects obliquely into the cavity region of the respective other running rail counter to the insertion direction of the running rail it stops. In particular in the case of a connecting element for two running rails having opposite insertion directions, the first inserted running rail, when inserted into the cavity region provided for it, pushes the insertion stop disk provided in this cavity region out of this cavity region, while the other insertion stop disk arranged in the cavity region provided for the other running rail which has not yet been inserted serves as a stop for the first inserted running rail. Since the running rail which is pushed in first if necessary is held securely in the connecting piece by the connecting claw, it itself acts as a stop for the other running rail which is pushed in later. The running rails can thereby be connected in such a way that the ends abut against one another without interruptions between the running rails. This results in a very good running stability of the vehicle guided in the running rail.

In an advantageous embodiment, the connecting claw and/or the insertion stop web are formed integrally, in particular stamped or cut out, from the connecting piece. Simple assembly and rapid and simple production can thereby be achieved. If the connecting claws and/or the structures for poking are hardened, the same or only slightly harder material than the running rail can be used for the connecting element in the one-piece connecting element without affecting a reliable connection.

In a further embodiment, which is also advantageous in terms of production, it can be provided that the connecting element has a connecting body, into which an elastic plate is inserted, which is formed with connecting claws and/or with insertion-limiting lugs. The coupling claws and/or the insertion stop lugs can therefore be produced simply from a harder material than the running rail, for example spring steel, while the coupling body can be produced from another material that is easier to machine.

In order to enable a simple, but secure connection of the spring plate to the connecting body, the spring plate has fastening tabs which engage in corresponding recesses of the connecting body. It is particularly advantageous if a part of the connecting web is designed as a snap-in connection which securely holds the spring plate on the connecting body, while the other fixing web is designed in the form of a stop which prevents the spring plate from moving when the running rail is pushed in the push-in direction.

If the connecting element according to the invention is used in the running rail system described at the outset, a particularly quick and simple installation without additional parts or tools can be advantageously achieved. Advantageously, the running rail is made of a softer material than the connecting claw, for example having a tensile strength of up to 400N/mm²Is made of the steel of (1). And in particular for a connection element with a connection body and an embedded spring plate, the material of the connection claw is advantageously at least comparable to that of the connection elementThe material of the rail is twice as hard and has, for example, 1700N/mm²The tensile strength of (2). For the one-piece connection, in particular when the connection claws or the structures for poking are hardened, it can be advantageous to use a material for the working rail which is identical to or only slightly softer than the material of the connection.

Drawings

The invention will now be described with reference to the accompanying drawings in conjunction with embodiments. In the figure:

fig. 1 shows a running rail system comprising two running rails and a connecting element, which are in a state of being separated from each other;

fig. 2 shows the running rail system according to fig. 1 in an assembled state;

figure 3 shows a three-dimensional view of a joint according to the invention according to a first embodiment of the invention;

FIG. 4 shows a middle longitudinal section through the connection according to FIG. 3;

fig. 5 shows a three-dimensional view of the elastic plate of the connection piece according to fig. 3;

fig. 6 shows a middle longitudinal section through the spring plate according to fig. 5;

fig. 7 shows a detail of the spring plate according to fig. 6;

fig. 8 shows a middle longitudinal section through the connecting piece according to fig. 3, with the running rails inserted;

fig. 9 shows a detail of the connection according to fig. 8;

fig. 10 shows a detail of the connection piece according to fig. 9 in a sectional view;

figure 11 shows another three-dimensional view of the connection piece according to figure 8;

FIG. 12 is a three-dimensional view of a connector according to another embodiment of the present invention;

figure 13 shows a detail of the coupling claw of the coupling piece according to figure 12;

FIG. 14 shows a detail of the push-in stop tab of the connector according to FIG. 12;

FIG. 15 shows another embodiment of a connecting jaw of the connector according to FIG. 12;

fig. 16 shows the view according to fig. 15 in a further perspective view.

Detailed Description

The running rail system shown by way of example in fig. 1 has a connecting part 1 into which two running rails 2, 2 'can be pushed from opposite push-in directions E, E' into one another. Fig. 2 shows the connected state. Since the connecting element 1 and the running rail 2 or 2 'are of substantially symmetrical design, corresponding components have the same reference numerals, wherein the components located to the left in the drawing on the basis of the center of the connecting element 1 are each marked with a prime (').

The connecting piece 1 and the running rails 2, 2' are each made of an essentially elongated steel hollow profile, one side of which has a break in the longitudinal direction. Such running rails 2, 2' are also referred to as C-rails. This cutout serves to receive the roller of the rail vehicle suspended on the running rails 2, 2'. As shown in particular in fig. 2, in the assembled state of the running rail system, the connecting element 1 surrounds the running rails 2 and 2 'which are pushed into the cavity H, H' of the connecting element.

As can be seen particularly well in fig. 4 and 8, the cavity H, H ' of the connecting part 1 can be divided into a cavity region H for the first running rail 2 and a cavity region H ' for the second running rail 2 '. In the present embodiment, the boundary between the cavity regions H, H' is located centrally in the longitudinal direction of the connector 1. However, in some alternative embodiments, cavity area H, H' may have different dimensions.

The connecting element 1 shown in detail in fig. 3 and 4 has a connecting body 3, the side walls of which, which are vertical in fig. 3, have guide tabs 4, 4'. The guide tabs 4, 4 'press the running rails 2, 2' from both sides in the inserted state of the running rails 2, 2 ', thus centering the running rails 2, 2' relative to the upright side walls of the connecting element 1. On the side opposite to the fracture side, the connector 3 has a plurality of notches, the functions of which are described later.

An elastic plate 5 is fixed to the inner side of the connecting body 3 on the upper side in fig. 3. The elastic plate 5, which can be observed particularly well in fig. 5 to 7, has a tensile strength of 1700N/mm²I.e. a tensile strength of 400N/mm²The steel of (a) is significantly harder. The spring plate 5 has fastening tabs 6, 6 'at its longitudinal ends, the fastening tabs 6, 6' being able to snap into an outer recess on the upper side of the connecting body 3 due to the spring elasticity of the spring plate 5, so that the spring plate 5 is held in the connecting body 3. In order to prevent the spring plate 5 from moving in the longitudinal direction of the connecting body 3, the further fastening tabs 7, 7' engage in the central recess on the upper side of the connecting body 3 and rest there directly against the end edges of the central recess. The fastening tabs 6, 6 'and 7, 7' thus serve to hold the spring plate 5 securely in the connecting body 3, so that a movement in the longitudinal direction of the connecting body 3 and a movement transverse to the connecting body 3 is avoided.

In order to ensure that the running rails 2, 2 ' which are completely pushed into the cavity H, H ' can no longer be easily pulled out of or dropped out of the connecting element 1, a fastening device is formed by the connecting claws 8, 8 ' arranged on the spring plate. In the state in which the spring plate 5 has been inserted into the body 3 in the respective push-in direction E, E ', the connection claws 8, 8 project obliquely into the cavity H or H'. The coupling claws 8, 8 ' comprise spring-elastic tongues 8a ', the tongues 8a ' each having a front edge 8b, 8b ' at their front end projecting into the cavity H or H '. In the relaxed state shown in fig. 7, the front edges 8b, 8 b' are oriented substantially perpendicular to the longitudinal axis of the connecting body 3.

Due to the resilient properties of the coupling claws 8, 8 ', the running rails 2, 2 ' can be pushed into the respective cavity region H or H ' without a large resistance. During the insertion, the press-fit connection claws 8, 8 'are pushed upward from the cavity H or H' toward the connection body 3. If, on the other hand, the running rail 2, 2 ' is attempted to be pulled out of the connecting part 1 again, the front edge 8b, 8b ' is pressed by the spring-back action of the tongue 8a, 8a ' against the surface of the running rail 2, 2 ' facing the front edge and, due to its high tensile strength or rigidity, penetrates into the running rail 2 or 2 '. The stronger the running rails 2, 2 'are drawn, the stronger the prestressing of the connecting claws 8, 8' and the stronger the inclined position of the connecting claws 8, 8 'towards the cavity H, H', i.e. the deeper the front edges 8b, 8b 'dig into the material of the running rails 2 or 2'.

Only above a predetermined high tension force, the contact force of the coupling claws 8, 8 'can be overcome and the running rails 2, 2' can be pulled out of the coupling part 1 again for the purpose of removal. To further simplify the extraction, two recesses are provided in the connecting body 3 in such a way that the front edges 8b, 8b 'of the connecting claws 8, 8' can be seen through these recesses and the front edges 8b, 8b 'can be lifted off the running rails 2, 2'. These gaps in the connecting body 3 can furthermore be checked: whether the front edge 8b, 8b 'penetrates sufficiently into the material of the running rail 2, 2'. This state can be seen particularly well in fig. 8 to 10, which fig. 8 to 10 show a connecting element 1 with a pushed-in running rail 2, 2'.

In order to ensure that the running rails 2, 2 'can only be pushed into the center of the connecting part 1 and thus only in the corresponding region H or H' of the cavity when the running rails 2, 2 'are pushed in, a push-in stop tab 9, 9' is provided on the spring plate 5. The push-in limiting lugs 9, 9 ' are formed by the parts of the spring plate 5 which project into the cavity region H or H ', wherein a respective stop edge 10 and 10 ' of the push-in limiting lugs 9, 9 ' serves as a stop for the running rails 2 and 2 ', respectively. In this case, the stop edges 10, 10 ' extend in a plane transverse to the insertion direction E or E ', i.e., in the present embodiment through a central plane of the connecting body 3 extending between the cavity regions H and H '. The push-in stop tab 9 and its stop edge 10 serve as a stop for the running rail 2 'which is pushed into the region H' of the cavity from the left, while the push-in stop tab 9 'and its stop edge 10' serve as a stop for the running rail 2 which is pushed into the region H of the cavity from the right in fig. 11.

As can be seen particularly well from fig. 11, the running rail 2 is initially pushed into the cavity region H from the right in fig. 11 until the running rail 2 strikes the stop edge 10 'of the insertion stop 9'. Since the coupling claw 8 then engages into the surface of the running rail 2, there is no risk of the running rail 2 being pulled out of the coupling piece 1 again by mistake. Furthermore, the insertion stop 9' ensures that the running rail 2 is only inserted into the center, i.e. only into the cavity region H of the connecting part 1. Subsequently, the running rail 2 ' is pushed into the cavity region H ' from the left in fig. 11, wherein the running rail 2 ' pushes the push-in stop tab 9 ' upward from the cavity region H ' toward the connecting body 3 at the end of the push-in process, which is easily achieved on the basis of the spring-elastic properties of the elastic plate 5. The running rail 2 which has been pushed in and fixed by the resilient claws 8 thus acts as a stop for the running rail 2'. The insertion stop web 9, which is not visible in fig. 11, is already pressed upward out of the cavity H when the first running rail 2 is inserted from the right in fig. 11, and the insertion stop web 9 is not effective when the running rails 2, 2' are inserted in this order. However, for simple assembly, the insertion-limiting lugs 9 and 9 ' are provided for both insertion directions E, E ', wherein one of the insertion-limiting lugs is inactive in the sequence of insertion of the running rails 2, 2 '.

As described above, the connecting element according to the invention allows a particularly simple mounting of the running rail system and a reliable connection is established.

While the spring plate 5 makes it possible in a simple manner to provide the connecting claws with the necessary spring elasticity characteristics while having a high stiffness and tensile strength with a low material consumption, the connecting body 3 in this embodiment can be made of a softer material which can be processed in a simpler manner in terms of manufacturing technology.

Fig. 12 to 13 show a further connecting element 11 according to the invention. The connecting element 11 differs from the connecting element 1 shown in fig. 1 to 11 mainly in that the connecting element 11 is formed in one piece and has differently designed resilient claws and insertion-limiting lugs. However, the basic functions of the connecting member, the elastic claw, and the push-in stopper piece are the same as above, and the differences are mainly studied below.

Unlike the connector 1, the connector 11 is integrally formed of one material. In order to ensure a good connection, a number of connection claws are formed directly from the connecting element 11 on the lateral and upper sides of the connecting element 11 in fig. 12, wherein for the sake of simplicity only the connection claws 12 are illustrated. However, the description of the coupling claw 12 applies in the same way to the other coupling claws of the coupling element 11. The production can advantageously be further simplified by the one-piece material, since no additional spring plate 5 is required.

As can be seen in connection with the coupling claw 12 shown in detail in fig. 13, the coupling claw 12 projects inwardly into the cavity H of the coupling piece 1. The inwardly projecting spring-elastic tongue 12a of the connecting element 11 ensures that the tip 12b of the connecting claw 12, which is slightly bent toward the running rail, can be pressed against the running rail 2 when the running rail 2 is pushed in. When the running rail 2 is extracted, the tongue 12a presses the tip 12b against the running rail 2, causing the tip 12b to dig into the running rail 2. Although the running rail 2 can be withdrawn with the application of a large force, chips are cut out of the material of the running rail 2. In this embodiment, the connecting member 11 may be made of the same material as the working rail 2 based on the shape of the tip 12b, so that a material of different hardness is not required. However, the disadvantage is that after a plurality of withdrawals of the running rail 2, the tip 12b of the connecting claw 12 is worn. A method of overcoming this disadvantage consists in hardening the tip 12b, which is preferably achieved by induction hardening. Importantly, the tip 12b is harder than the material of the running rail 2.

Fig. 14 shows in detail the insertion-limiting lugs 13, 13' which are likewise formed by the connecting piece 11. These push-in stopper pieces 13, 13 'work substantially the same as the push-in stopper pieces 9, 9' of the first embodiment described above. The insertion limiting lugs 13, 13 'also have stop edges 14, 14' which are designed as stops for the respective other guide rail 2 'or 2 and which extend obliquely into the cavity H, H', the stop edges 14, 14 'extending in a plane transverse to the insertion direction E or E'. The stop edge 14 still limits the insertion of the running rail 2 ' into the cavity region H ', while the stop edge 14 ' limits the insertion of the running rail 2 into the cavity region H. Since the insertion-limiting lugs 13, 13 'spring-elastically into the corresponding cavity regions H, H', the insertion-limiting lugs 13, 13 'can be pressed out of the cavity regions H, H' when the running rails 2, 2 'are inserted, so that the running rails 2, 2' can be pushed together in abutment with one another. As described in detail above for the connection element 1, the running rail 2 which is pushed in first, which first strikes against the stop edge 14 ' of the push-in stop lug 13 ', itself acts as a stop for the second running rail 2 ' which is then pushed in.

In fig. 15 and 16, the connecting element 11 has connecting claws formed in an alternative manner, which are exemplarily illustrated in connection with the connecting claw 15. The connecting claw 15 is formed by the link 11 as the connecting claw 12, but does not have the curved tip 13 b. And the structure for stabbing is formed by a cutting edge 15a on the front end of the tongue piece 15a of the spring elastically protruding into the cavity H. Since the connecting claws 15 are stamped out of the original shape of the connecting piece 11 in the present exemplary embodiment, the stamped-out edges of the connecting claws 15 have a stamped-out burr. Unlike conventional practice, these punch burrs are not removed, but instead sharp cutting edges 15b are provided by these punch burrs, which cutting edges 15b advantageously cut into or dig into the running rail 2 when the running rail 2 is withdrawn. Such a cutting burr can also be produced by producing the connecting claw 15 by cutting, for example by laser cutting. The connecting element 11 can also be made of the same or a slightly harder material than the running rail 2. The cutting edge 15b can also be hardened in an advantageous manner.

In an alternative embodiment, instead of the symmetrically formed (two) halves shown here, the connecting element can also have connecting regions of different sizes for the running rails. The connector may also be configured as a coupling for a variety of different connection systems. A conventional connecting element, for example a bolt, can be provided on one side and a connecting claw according to the invention on the other side.

Claims (21)

1. A connecting element (1; 11) for running rails (2, 2 '), having a first cavity (H) and a second cavity (H ') for receiving a first running rail (2) and a second running rail (2 '), respectively, and a securing device for preventing the first running rail (2) and the second running rail (2 ') from being pulled out of the first cavity (H) and the second cavity (H '), respectively, characterized in that the securing device has at least one spring-elastic first coupling claw (8; 12; 15) which, in the relaxed state, projects obliquely into the first cavity (H) in the insertion direction (E) of the first running rail (2); the at least one first connecting claw (8; 12; 15) is formed to be pressed out of the first cavity (H) by the first running rail (2) from a relaxed state when the first running rail is pushed in, and to be resiliently embedded in the material of the first running rail (2) when the first running rail is withdrawn.

2. The connecting element (1; 11) according to claim 1, characterised in that the first connecting claw (8; 12; 15) has a spring-elastic tongue (8 a; 12 a; 15a) which projects obliquely inward into the first cavity (H) in the insertion direction (E).

3. The connecting element (1; 11) according to claim 2, characterized in that the front end of the first connecting claw (8; 12; 15) projecting into the first cavity (H) is configured as a formation (8 b; 12 b; 15b) for stabbing into the first running rail (2).

4. The connection piece (1; 11) according to claim 3, wherein the structure for stabbing is a cutting edge (8 b; 15b) or a tip (12 b).

5. Connection piece (1; 11) according to claim 4, characterized in that the structure (8 b; 12b) for stabbing is bent towards the direction of the first running rail (2) to be pushed into the first cavity.

6. Connection piece (1; 11) according to claim 3, characterized in that the fixing means have a spring-elastic second connecting claw (8 '; 12'; 15 ') which in the relaxed state projects obliquely into the second cavity (H') in the push-in direction (E ') of the second running rail (2').

7. Connection piece (1; 11) according to claim 6, characterized in that, for limiting the pushing-in of the first running rail (2) in its push-in direction (E) into the first cavity (H) provided for it, a first spring-elastic push-in limiting tab (9 '; 13') is provided, which is provided on the connection piece (1; 11) and which protrudes into the second cavity (H ') provided for the second running rail (2').

8. Connecting element (1; 11) according to claim 7, characterized in that the stop edge (10 ', 14') of the first insertion stop (9 '; 13') extends in a plane perpendicular to the insertion direction (E) of the first running rail (2).

9. Connection piece (1; 11) according to claim 7 or 8, characterized in that the first push-in limiting tab (9 '; 13') in the relaxed state projects obliquely into the second cavity (H ') provided for the second running rail (2') and is configured to be pressed out of the second cavity (H ') by the second running rail (2') when pushed in.

10. Connection piece (1; 11) according to claim 7 or 8, characterized in that, for the purpose of limiting the insertion of the second running rail (2 ') in its insertion direction (E ') into the second cavity (H ') provided for it, a second spring-elastic insertion-limiting tab (9; 13) is provided on the connection piece (1; 11), which in the relaxed state projects obliquely into the first cavity (H) provided for the first running rail (2) and is configured to be pressed out of the first cavity (H) by the first running rail (2) when it is inserted.

11. The connecting element (11) according to claim 10, characterized in that the first and second connecting claws (12, 12 '; 15) and/or the first and second push-in limiting lugs (13, 13') are formed integrally by the connecting element (11).

12. The connecting element (11) according to claim 11, wherein the first and second connection claws (12, 12 '; 15) and/or the first and second push-in limiting tabs (13, 13') are stamped or cut out of the connecting element (11).

13. The connecting element (1) according to claim 10, characterised in that the first and second connecting claws (8, 8 ') and/or the first and second push-in limiting tabs (9, 9') are formed by an elastic plate (5) which is fixed in the connecting body (3) of the connecting element (1).

14. Connecting element (1) according to claim 13, characterized in that the elastic plate (5) has fixing tabs (6, 6 ', 7') for fixing on the connecting body (3), which engage into corresponding indentations of the connecting body (3).

15. Connection piece (1; 11) according to claim 14, characterized in that the first and second connection claws (8, 8 '; 12, 12 '; 15) and/or the first and second push-in limiting tabs (9, 9 '; 13, 13 ') and/or the fixing tabs (6, 6 ', 7 ') and/or the elastic plate (5) are made of a harder material than the running rails (2, 2 ').

16. Connection piece (1; 11) according to claim 15, characterized in that the first and second connection claws (8, 8 '; 12, 12'; 15) and/or the first and second push-in limiting tabs (9, 9 '; 13, 13') and/or the fixing tabs (6, 6 ', 7') and/or the elastic plate (5) are made of spring steel.

17. The connecting element (11) according to claim 6, characterized in that said first and second connecting jaws (12, 12', 15) and/or said structure for stabbing (8 b; 12 b; 15b) are hardened.

18. Work rail system with a plurality of work rails (2, 2') that can be connected by means of a connecting piece (1; 11), characterized in that the connecting piece (1; 11) is constructed according to one of the preceding claims.

19. Running rail system according to claim 18, characterized in that the running rail (2, 2 ') is made of a softer material than the first and second connecting claws (8, 8 '; 12, 12 '; 15) of the connecting piece (1; 11).

20. Work rail system according to claim 18 or 19, characterized in that the work rail (2, 2') is formed with a tensile strength of up to 400N/mm²Is made of the steel of (1).

21. Running rail system according to claim 18 or 19, characterized in that the tensile strength of the first and second connecting claws (8, 8 '; 12, 12 '; 15) is at least twice the tensile strength of the running rail (2, 2 ').