UA110888C2 - Guide plate for mounting rails for rail vehicles - Google Patents

Abstract

The invention provides a guide plate for attaching rails (S) for rail vehicles with even reduced weight and optimized performance. For this purpose, the guide plate has at least one molded from the lower side (11), on which the guide plate (3) is in the mounted position, inside the guide plate (3) the recess (30-34), made on the upper side (10) of the guide plate (10). 3) a support surface (13) for the resilient element (1, 2) provided for clamping the mounting rail (S), and a surface (9) made in the end face of the guide plate extending in the longitudinal direction of the guide plate (3) and on which side it is directed in the mounted position is reinforced and the rail (S). According to the invention, at least one reinforcement rib (21) extends over the upper side (10) of the guide plate (3), which rises above the support surface (13) and extends transversely to the surface (9) of the fit. At the same time, the notch (30) formed from the underside (11) inside the guide plate (3) extends into the region of the guide plate (3), in which the reinforcement rib (21) is made.

Description

The invention relates to a guide plate for fastening rails for rail vehicles.

In addition to the guide plate of the type discussed here, the system for attaching the rails typically includes at least one resilient element and a clamping element for securing the resilient element relative to the corresponding substructure of the track, on which the attachment point for the corresponding rail is to be formed by the system.

In the assembled position, the guide plate with a contact surface made on the long side of the guide plate abuts laterally against the sole of the mounting rail.

Under the lower structure of the track, on which the guide plate is mounted, a sleeper is typically understood, consisting, for example, of concrete, wood or other suitable material. In the lower structure of the track in the embodiment, there is a support shelf, which can be made according to the shape of the lower structure of the track or an additional element. On the support shelf in the ready-assembled system is fixed a guide plate, made with a bearing surface provided on the long side of the guide plate, and which lies opposite the long side equipped with an abutment surface. Alternatively, the guide plate can be rigidly held on the corresponding substructure of the track also by means of a separate fastening element.

In practical use, the guide plate performs a double function. On the one hand, it guides the rail from the side and ensures its correct longitudinal correction. At the same time, in the ready position mounted on the rail way, it diverts the transverse forces that occur in each case when moving through the reinforced rail at the corresponding attachment point, to the lower structure of the track. On the other hand, in the ready-mounted rail fastening system, the elastic element is reinforced and directed on the guide plates. This elastic element performs an elastic pressing force, with the help of which the rail is kept pressed against the corresponding lower structure of the track.

In the case when the guide plate is made in the form of a so-called "angle guide plate", then on the lower side of the guide plate facing the corresponding lower structure of the track, a ledge is made, extending in the longitudinal direction of the guide plate, which in the assembled position sits with geometrical locking in the corresponding shaped recess of the lower structure of the track. Thus, in addition to the support on the corresponding support shelf, the position of the guide plate across the longitudinal length of the rail is additionally ensured.

In order to secure the spring located on the guide plate relative to the lower track structure, a through hole is formed in the guide plate, usually directed from its upper side to its lower side. A clamping element, which is connected to the lower structure of the track carrying the rail, is inserted into this passage hole, which is necessary for clamping the corresponding elastic element. As a rule, the clamping element is a screw or threaded bolt, which is screwed into the frame, which is mounted in the lower structure of the track. For reliable retention of the elastic element, also under the influence of the forces acting in the working assembled state, in the correspondingly proposed position, on the upper side of the guide plate, shaped elements such as protrusions or recesses can be made, in which or on which the elastic element is fixed in each case by its plot

The resilient element used to press the rail typically has a mounting portion and at least one shelf portion extending from the mounting portion, which, in the operationally assembled state, presses against the rail with its free end.

Examples of guide plates of the type explained above and mounting systems or rail attachment points formed for the use of such guide plates are presented in CE 102 54 679

B4, OE 41 01 198 C1, OE 20 in 2004 020 816 01, UMO 2011/110454 AT or RE 20 in 2009 004 399

MI, as well as in practice in a large number of variants of implementation in use.

Guide plates of the type described above are made, as a rule, from plastics with a high load. To ensure in practical use the possibility of reliable resistance to the load acting on them, older versions of implementation were made, as a rule, massive. The recent demand for weight reduction can be met by having notches formed in a suitable location in the guide plate. Thus, in the guide plate described in CE 102 54 670 B4, in the areas where there is no need either to support the elastic element or to drain the liquid that falls on the guide plate, both outlets from the upper side and exit from the lower side of the notch. The shape of the notches, as well as the shape and orientation of the sections of the wall remaining between them, of the guide plate are chosen in such a way that, on the one hand,

high resistance to deformation of the guide plate is ensured and, on the other hand, a significant reduction in weight is achieved.

Along with its support function and direction function, the guide plate of the type discussed here should also provide good electrical isolation of the fixed on it and the structural elements that come into contact with it, relative to the lower structure of the track. To fulfill this requirement, it was proposed, for example, in UMO 2011/110454 A1 to surround the passage hole of the guide plate with a circular flange.

The embankment prevents, like a protective dam, the penetration of water into the opening.

At the same time, the flap can be used with the appropriate shape of the elastic element as a guide for the elastic element.

Even if the guide plates made in the framework of the method described above have optimized operational properties with reduced weight, practice has set the goal of providing a highly loaded guide plate with even more reduced weight.

According to the invention, this goal was achieved with the help of a guide plate with the features set forth in clause 1 of the claims.

The best variants of the invention are set forth in the dependent clauses of the claims and explained further as the general essence of the invention in detail.

According to the invention, the guide plate for fastening rails for rail vehicles has, in accordance with the previously explained state of the art, at least one formed from the lower side on which the guide plate stands in the mounted position, inside the guide plate, a recess, made on the upper side of the guide plate, a support surface for the elastic element provided for pressing the reinforced rail, and the abutment surface made in the end face of the guide plate, which extends in the longitudinal direction of the guide plate and along which the reinforced rail is directed laterally in the mounted position.

According to the invention, a reinforcement rib is made on the upper side of the guide plate, which also rises above the support surface and extends transversely to the contact surface. At the same time, the groove formed from the lower side inside the guide plate goes into the area of the guide plate in which the reinforcement rib is made.

The guide plate according to the invention has at least one rib in the form of a stiffening rib or a rib on its upper side provided by the support surface for the elastic element fixed on the guide plate in each case, which increases the rigidity of the guide plate structure. This makes it possible to expand the groove formed from the lower side inside the guide plate also in the region of the volume of the guide plate, over which the reinforcement rib extends. Since a small wall thickness is enough for the reinforcing effect of the reinforcement rib, the reinforcement rib itself can be made, thus, to a large extent hollow. In general, in this way it is possible to further reduce the volume of the material of the guide plate and thereby, accordingly, its weight, without causing damage to its load capacity and other mechanical properties.

Depending on the execution of the adjacent shaped elements of the guide plate, the shape of the section inserted inside the reinforced area of the guide plate overlapped by the rib corresponds to the shape of the notch formed in the guide plate. At the same time, it optimally follows the shape of the reinforcing rib in its longitudinal direction and transverse direction in such a way that the reinforcing rib is hollow enough to only provide the necessary wall thickness for the formation of its side walls and its roof.

The guide plate according to the invention can be mounted in the same way as the prior art guide plates explained above. Accordingly, the guide plate according to the invention typically also has a through hole directed from the upper side to the lower side of the guide plate, through which the clamping element provided for the clamp of the elastic element is inserted. In order to prevent in this case, taking into account the state of the art, the penetration of water or other liquids falling on the guide plate into the through hole, and, also as in the state of the art, the neck of the through hole correlated with the support surface can be surrounded, at least in parts, raised above support surface of unloading. At the same time, it can also serve as a guide for a section of an appropriately formed, mounted on a guide plate elastic element. In this connection, an optimally reinforcing and at the same time technologically simple design of the guide plate according to the invention can be obtained in the case when the reinforcement rib is attached to the sidewall. At the same time, the connection of the reinforcement rib to the rib can be formed in such a smooth way that optimal force transmission is obtained, and the rib as a continuation of the reinforcement strengthens the guide plate along its entire width.

Along with the already mentioned flange, which forms a barrier against the penetration of liquid into the passage hole, other shaped elements for the direction of the elastic element can be made on the support surface of the guide plate in an essentially known way. By these shaped elements can be meant, for example, limiters, to which in the mounted position one section of the elastic element adjoins in each case, or a groove in which the elastic element sits in the assembled position with its other section. Also by corresponding shaped members may be meant a concavity of slight depth by which a pre-mounted position is given, in which the spring element is supported pre-assembled under a slight pre-tension until the rail is installed in its position according to the assignment and the spring element can move in its final position.

Two grooves can be formed on the support surface of the guide plate, extending in the longitudinal direction of the guide plate, in which in the mounted position in each case at least one area rests against the elastic element. At the same time, the grooves can be located in such a way that they are separated from each other by a reinforcement rib made according to the invention on the upper side of the guide plate.

Thus, despite the presence of grooves, the reinforcing rib can extend across the entire width of the guide plate and perform its strengthening function. With the appropriate shape of the elastic element, the reinforcement rib can additionally serve as a guide or support for the corresponding section, which stands in the mounted position in the groove. To ensure that there is no accumulation of large amounts of liquid in the area of the grooves, the grooves, at least in sections, can be lowered in the direction of their reinforced end facing away from the rib. Thus, the liquid entering the grooves can flow out of the grooves from the side.

It goes without saying that if it is appropriate, for example, for technological reasons or on the basis of static loads, two or more recesses can be formed from the lower side inside the guide plate. There can be notches located next to each other

At the same time, they are limited by jumpers, which are located in the form of a half-timbered structure and thus have an optimal bearing capacity with a minimized amount of material.

In the event that the corresponding recess extends over a large volume of the guide plate, it may be appropriate, for example, on the roof facing the upper side of the guide plate of the corresponding recess to perform at least one rib, which also acts as a reinforcement. It is also possible to form recesses on the upper side inside the guide plate to save material. Alternatively, it is also intended to introduce gaps that are directed from the upper to the lower side of the guide plate for the same purpose. At the same time, the corresponding gaps can be made in such a way that they fall into the groove formed from the lower side inside the guide plate.

The guide plate according to the invention typically has an elongated, rectangular parallelepiped-like basic shape, which in the assembled position is longer along its long sides directed parallel to the reinforced rail than along its narrow sides located transversely to them.

The protection of the guide plate according to the invention against the liquid that appears, primarily water, which collects during rain in the environment of the guide plate, and at the same time, its insulating effect can be increased by means of the fact that the guide plate has a known substantially distant from it on the side protrusions that form, for the surfaces associated with the lower side of the guide plate, a continuation of the bearing surface made on the lower side of the guide plate, with the help of which the guide plate stands in the mounted position on the corresponding lower track structure.

At the same time, the protrusions can extend along the narrow sides and along the long side of the guide plate, which lies opposite the contact surface. On the corresponding long side, in addition, a support surface can also be made in a known manner, with the help of which the guide plate rests in the mounted position on the shelf of the lower structure of the track, on which the guide plate is mounted. At the same time, the protrusions can be made in the form of thin boards, which are tightly located in the mounted position on the upper side of the lower structure of the track. It is sufficient if the protrusions have a thickness that is only a small fraction of the thickness of the main body of the guide plate on which they are formed.

According to the invention, the design of the guide plate is particularly suitable for its production from plastic. Thus, the reinforcement rib provided according to the invention can be produced without problems within the framework of the usual manufacturing method from plastic, which is already used for the production of guide plates at this time.

The advantages of the invention are manifested for ordinary guide plates intended for installation on a flat surface as positively as for guide plates made in the form of angular guide plates, for the installation of which a recess should be provided in the corresponding lower structure of the track, in which the angular section of the guides is correlated plates are planted in the assembled position with geometric locking.

In the future, the invention is explained in more detail with the help of variants of implementation. In each case, it is schematically shown:

Fig. 1 - attachment point for the rail in a side partially cut view,

Fig. 2 - elastic clamp in a perspective view,

Fig. C - mounted in the system according to fig. 1 guide plate in a perspective view from above,

Fig. 4 - guide plate in a perspective view from below.

In the presented in fig. 1 point B fastening of the rail 5 is fixed on the shown in this case only partially cast concrete sleeper OO, which forms a solid, supporting rail 5 lower structure of the track.

A flat bearing surface 01, which is limited on its narrow sides in each case by a shelf Ш2, 03, is formed on the transversely to the longitudinal length of the rail 5 sleeper SHO in a substantially known way. In the region of the transition of the bearing surface О1 to the corresponding shelf

Ц2, ОЗ in the sleeper О in each case, one groove-like depression Ш4, О5 is made, which extends along the width of the sleeper Ш measured in the longitudinal direction of the reinforced rail 5 and is directed at the mounting point B parallel to the rail 5, which is assembled to the state of readiness.

The fastening point B is formed by a system for fastening the rail 5, containing two elastic clamps 1, 2, which serve as elastic elements, as well as two guide plates 3, 4, two necessary as clamping devices for clamping the corresponding elastic clamp 1, 2 tightening screws 5 , 6 and the supporting plate 7.

As shown in fig. 2 on the basis of the elastic clamp 1, the identically formed elastic clamps 1, 2 are made M/-similar in essence in a known way and have in each case one middle loop Ta, the shoulders 16, 1c of which are connected to each other at one end by means of of the arc section 14, covering a semicircle and passing at their other end in each case into the outwardly directed section 1e, 17 of twisting, to which the upwardly curved spring lever 19, 1j is attached in each case. Spring levers 19, 1 and pass in each case into the end section 1, 1), which is facing the direction of the middle loop And in such a way that the ends of the end sections 11, 1) are directed against each other. With its final sections, 1| the elastic clamp in its working mounted state presses on the side facing it of the sole of the E rail

WITH.

In each case, one of the elastic clamps 1, 2, one of the guide plates 3, 4 and one of the tightening screws 5, 6 are located on one of the long sides of the rail 5, while the backing plate 7 stands between the guide plates 3, 4 and is located on the bearing surface of the sleeper Ш1 |. On the supporting plate 7, the rail 5 stands with its PE sole.

The guide plates 3, 4 are made in this case in the form of corner guide plates and have a ledge on their lower side facing the sleeper О, which extends along the width measured in the longitudinal direction of the rail 5, which, when the guide plate З is in the assembled position, in in each case, it sits with a geometric closure in the corresponding and formed joint depression 04, О5 sleepers |.

In addition, the guide plates 3, 4 in the mounted position rest in each case with their supporting surface 8 made on the long side facing away from the rail 5 against the shelf Ш2,

OZ sleepers W. On its opposite sides, facing the sole E of the rail, which represent the end face of the guide plate. From the long sides, the guide plates 3, 4 have in each case a contact surface 9, against which the sole E of the rail abuts with its longitudinal edge. Thus, the transverse forces C) generated when the rail vehicle (not shown here) moves the rail 5) are perceived by the guide plates 3, 4 and are transferred to the sleeper y.

The identical design of the guide plates 3, 4 is explained on the example shown in fig. With and 4 guide plates 3.

In the guide plate Z, a through hole 12, made in the form of a longitudinal hole, is formed, directed from the upper side 10 to the lower side 11 of the sleeper Ш lying opposite it and facing the bearing surface 01, which is centrally located relative to the length of the guide plate 3, 4 and with by a shift in the direction of the abutment of the long sides of the guide plate 3, 4 equipped with a surface 9. Through the through hole 12 during the installation of the point B of the fastener for clamping the elastic clamps 1 located on the guide plate C, a clamping screw 5 is inserted, which is then screwed into the sleeper Ш and not shown here is a crutch.

On the upper side 10 of the guide plate C, a support surface 13 is made, on which the elastic clamp 1 is fixed in the mounted position. At the same time, the support surface 13 is not made flat, but has different shaped elements that serve for the direction and support of the elastic clamp 1.

These include the abutment surfaces 14, 15 rising in the direction provided by the surface 9 of the abutment of the long sides of the guide plate C and adjacent to this long side, of which in each case one when viewed in the longitudinal direction is located on the side on each side of the through hole 12. In addition to this, there are two stops 16, 17 on the support surface 13, one of which in each case faces the support surfaces 14, 15.

The limiters 16, 17 together with the support surfaces 14, 15 form a seat in which the end sections T, 1|) of the elastic clamp 1 are temporarily supported in the pre-assembly position until they are moved after positioning the rail 5 for final assembly on the support surfaces 14, 15 on the sole E of rail 5.

In addition, on the support surface 13, the surrounding neck of the through hole 12 is made of a bulkhead 18. On the one hand, this bulkhead 18 prevents the penetration of liquids falling on the support surface 13 into the through hole 12. At the same time, the bulkhead 18 has a thin-walled growth 18a, which serves for additional protection, which is located in the mounted position below the level of the support surface 13 of the internal thread of the corresponding tightening screw 5, 6 from dirt and to simultaneously increase the electrical resistance. On the other hand, the flange 18, in its raised area facing the long side of the guide plate Z facing the provided surface 9, serves as a guide for the arc section and the elastic clamp 1.

In addition, two grooves 19, 20 are formed in the support surface 13, which are located in the longitudinal direction on the same line with each other, as well as adjacent to the supplied support surface 8 on the long side and parallel to it. At the same time, the grooves 19, 20 end in each case on the narrow side Za, 36 of the guide plate 3. At the same time, they are beveled with a decrease in the direction of their respective narrow side Za, ZB ends in such a way

In such a way that the liquid entering the grooves, such as water, flows out laterally through the narrow sides of the grooves 19, 20.

The grooves 19, 20 are separated from each other by a reinforcement rib 21, which is located on the support surface 13 centrally relative to its length and extends in the direction of the width of the guide plate With the transversely supplied support surface 8 and the surface 9 of adjacency to the long side of the guide plate 3. Moving away from the supplied support surface 8 of the long side of the guide plate 3, the reinforcement rib 21 approaches the surrounding neck of the passage opening 12 of the flange 18. At the same time, the width of the reinforcement rib 21 continuously decreases in the direction of the flange 18 until it passes in the rounding of its faces 22, 23 into the corresponding outer surface 24 , 25 flange 18. The flange 18 thus forms a continuation of the reinforcement rib 21 and complements the strengthening effect of the reinforcement rib 21 in the area surrounded by the through hole 12 of the edge of the guide plate 3.

On the narrow sides За, ЗБ and on the long side of the guide plate Z provided by the support surface 8, edge-like protrusions 26, 27, 28 are formed, which stand aside from the guide plate Z and overlap in the mounted position on the surrounding guide plate Z of the sleeper section). In this way, the protection of the upper side of the guide plate Z from water that appears in or on the sleeper Y is improved. At the same time, the thickness p of the protrusions 26-28 is at most one tenth of the thickness O" of the main body 29 of the guide plate 3.

A large number of recesses 30, 31, 32, 33, 34 are formed from its lower side 11 inside the guide plate C. At the same time, the recess 30 is formed in that area of the guide plate 3, in which the rib 21 of reinforcement is made on the upper side 10. The shape of the correlated rib 21 of the reinforcement of the recess 30 is adapted to the shape of the rib 21 of the reinforcement. According to this, the recess 30, departing from its wide edge, which is correlated with the support surface 8 provided by the long side, extends in the direction of the through hole 12 until only a thin bridge 35 remains between the recess 30 and the through hole 12. In general, thus , the reinforcement rib 21 on its side facing the lower side 11 is hollow up to the thin wall thickness.

Other recesses 31-34 when viewed in the longitudinal direction are in each case symmetrically located relative to the middle of the guide plate 3. At the same time, adjacent recesses 31-34 are separated from each other by jumpers, which in the form of half-timbered struts are directed in each case in such a way that the guide plate C has high hardness also in its area provided with notches 31-34.

Thanks to the reinforcement rib 21 and the recess 30 formed in it, a prerequisite is thus created so that identically designed guide plates 3, 4 can be made with a minimum amount of material and, accordingly, with a minimum weight, and at the same time can reliably fulfill the requirements proposed to the load capacity of such guide plates 3, 4.

The decrease in hardness due to the saving of material is compensated by the reinforcement rib 21, which significantly increases the moment of inertia of the cross-sectional area on average due to the area of the corresponding guide plate 3, 4 supplied by the reinforcement rib 21. Thus, the guide plates 3, 4 are strengthened and achieve an overall higher load capacity . For the direction of force transmission around the through hole 12 made in the form of a longitudinal hole, the longitudinal hole is surrounded by an extended flange 18, which smoothly transitions into the reinforcement rib 21. A construction suitable for a plastic product assumes that the reinforcement rib 21 is made hollow from the lower side 11, and in the region of the reinforcement rib 21 is provided with a constant wall thickness.

REFERRAL DESIGNATIONS

B - attachment point r' - thickness of protrusions 26-28 r" - thickness of the main body 29

E - the sole of rail 5

Y is the length of the guide plate Z

O - transverse forces

C - rail

M - sleeper

МО - bearing surface of sleeper 0 2, ОЗ - shelves of sleeper О

О4, 05 - deepening of sleeper 1a - middle loop of elastic clamp 1 15, 1c - shoulder of middle loop я 1a - arc section of middle loop and

Te, 171 - twisting sections of elastic clamp 1 19, 1 - spring lever of elastic clamp 1 1st, 1) - end sections of elastic clamp 1 1, 2 - elastic clamps (elastic element)

C, 4 - guide plates

Za, Zb - the narrow sides of the guide plate Z

B, 6 - clamping screws 7 - supporting plate 8 - support surface 9 - contact surface 10 - upper side of the guide plate C 11 - lower side of the guide plate C 12 - through hole of the guide plate C 13 - support surface of the guide plate C 14, 15 - stop surfaces of the guide plate C 16, 17 - limiters of the guide plate C 18 - flange of the guide plate C 1va - growth of the flange 18 19, 20 - grooves of the guide plate C 21 - rib of the guide plate C 22, 23 - side surfaces of the rib 21 reinforcement 24, 25 - outer surfaces of removal 18 26, 27, 28 - protrusions 29 - main body 30-34 - recesses 35 - bridge

Claims (12)

FORMULA OF THE INVENTION 1. Guide plate for fastening rails (5) for rail vehicles, - with at least one recess (30-34) formed from the lower side (11), on which the guide plate (3) stands in the mounted position, inside the guide plate (3), - 3 made on the upper side (10) of the guide plate (3) ) a support surface (13) for an elastic element (1, 2) provided for pressing the reinforced rail (5), and - with a contact surface (9) made in the end face of the guide plate (3) extending in the longitudinal direction of the guide plate (3) ) and along which side the reinforced rail (5) is directed in the assembled position, which is characterized by the fact that on the upper side (10) of the guide plate (3) at least one reinforcement rib (21) is made, which rises above the support surface (13) and extends across the contact surface (9), and that the recess (30) formed from the lower side (11) inside the guide plate (3) goes into the area of the guide plate (3), in which the reinforcement rib (21) is made. 2. The guide plate according to claim 1, which is characterized in that it has a through hole (12) directed from the upper side (10) to the lower side (11) of the guide plate (3) for inserting a clamping element (5, 6) provided for clamping of the elastic element (1, 2), which correlates with the support surface (13) of the neck of the through hole (12), at least in parts, surrounds the flange (18) raised above the support surface (13), and that the reinforcing rib (21) is attached to the flange (18). 3. The guide plate according to any of the previous items, which is characterized by the fact that the support surface (13) has shaped elements for the direction of the elastic element (1, 2). 4. The guide plate according to claim 2 or claim 3, which is characterized by the fact that the part of the removal (18) is made to guide the surrounded part in the mounted position of the loop (1a) of the elastic element (1, 2). 5. Guide plate according to any of paragraphs With or 4, which differs in that two grooves (19, 20) are formed in the support surface (13), which extend in the longitudinal direction of the guide plate (3) and in which, in the mounted position, at least one area (16, 11) resists the elastic element (1, 2), and that the grooves (19, 20) are separated from each other by a rib (21) of reinforcement. 6. Guide plate according to claim 5, which is characterized by the fact that the grooves (19, 20), at least 3 sections, are lowered in the direction of their strengthening end facing away from the rib (21). 7. The guide plate according to any of the previous items, which differs in that more than two recesses (30-34) are formed from the lower side (11) inside the guide plate (3). 8. Guide plate according to claim 7, which is characterized by the fact that adjacently located recesses (30-34) are limited by jumpers (35), which are arranged in a half-timbered type. 9. The guide plate according to any of the preceding points, which is characterized by the fact that it has lateral protrusions (26-28) that are distant from it, correlated with the lower side (11) of the guide plate (3), the surfaces of which form a continuation of the one made on the lower side (11) of the guide plate (3) of the bearing surface (01), with the help of which the guide plate (3) stands in the mounted position on the corresponding lower structure of the track. 10. The guide plate according to any of the previous items, characterized in that the protrusions (26-28) extend along the narrow sides (Za, 30) and along the long side of the guide plate (3) lying opposite the surface (9) of the abutment . 11. Guide plate according to claim 9 or claim 10, which is characterized by the fact that the protrusions (26-28) have a smaller thickness (0) than the main body (29) of the guide plate (3). 12. The guide plate according to any of the previous items, which is characterized by the fact that it is molded from plastic.