PT89084B - DEVICE FOR FIXING A RAILWAY RAIL ON A CRANK, CONSTITUTED BY A GARROT AND A CUNHA - Google Patents

Abstract

This device comprises an elastic sole 2 between the rail and the sleeper, a stop 3 on each side of the flange 4 of the rail, an insert 7 on each side of the rail, and two attachments 5a, 5b bearing on the flange 4 of the rail and designed to work together with the inserts 7, characterised in that each insert comprises a branch 15 parallel to the rail and creating a free space 16 under the said branch 15. The attachments 5a, 5b each have a loop 6a, 6b, one external part 30, 70 of which bears on the flange 4 in a gripping position while one internal part 32, 72 of the loop is inserted forcibly under the said branch 15 of the insert to exert a gripping pressure on the rail flange. Ease of positioning of the fixing attachment is obtained. <IMAGE>

Description

Description of the object of the invention that

ALLDVARD INDUSTRIES, Sociéte

Anonyme, French, industrial, headquartered in Chemin de Malacher, 3824o MEYLAN, France, intends to obtain in Portugal, for: DEVICE FOR FIXING A RAILWAY RAIL ON A PLATE CONTAINED BY A GARROTE AND A WEDGE The present invention refers to to a device for fixing a railway track on a crosspiece, withers and wedge.

A more or less elastic and cushioning base is arranged between the rail and the crosspiece. In order to keep the rail always pressed against the base, despite the displacements of one in relation to the other, to keep the distance between the two rows of rails within the permitted limits, despite the oblique efforts that come from the rolling material and to prevent the rail to walk, that is to say, to slide longitudinally with respect to the beam under the effect of braking, deceleration, acceleration or due to temperature variations, an elastic rail fixing device relative to the crossbar is required: elastic because this device holds a part that has a spring function.

Generally, such a device comprises a spring-loaded tourniquet anchored or retained by various means in the crosspiece or

NGV. 1385

6th .451

Ref: H. 1 ^ 204 Cas 4

3 / JBB / FRP

Mod. 71 - 10 000 βχ - 4-87 in the intermediate metallic saddle between the rail and the crosspiece. In addition to this anchoring part, the tourniquet includes, of course, a part intended to come to press the rail elastically (usually on the upper part of the skate). The tourniquet anchoring device, relative to the crosspiece, is such that, when placing the tourniquet, it is forced to deform the tourniquet although always within the areas of elasticity of the material chosen for that tourniquet. This deformation is accompanied by an accumulation of elastic energy; it is the very principle of a spring function.

In French patent FR 2 365 00 3 (THE TEMPERED SPREC), the tourniquet consists of an arc clamp, one end of which forms the base is displaced laterally in relation to the other end forming a tree it is inserted into a crack in the anchor, so that its base-forming end touches the rail skid and that the fitting of the tree-forming part to the anchoring member retains the torsion tourniquet. two ends prevents the anchor from being involved in the tourniquet and makes the tourniquet very deformable in relation to the elevation or swinging of the rail, since the tourniquet has only two points of contact; one with the rail at the level of the end that forms the base and the other with the anchoring organ by insertion in a crack of said organ.

In addition, in this patent, the plane of the rim shape and the flexion plane are parallel to the rail.

In US patent 4 J12 478 (MATSUO) the fixing organ or wedge has its active part perpendicular to the rail and, in addition, the withers are attached to the wedge through an opening in which a-260.451

Ref: H 15204 Cas 4

03 / JBB / FRP

Mod. 71 - 10 000 βχ - 4-87 store a part of the said wedge, preventing any placement of the withers by means of lateral translation parallel to the rail.

In patent DE 1 130 461 (VOSSLOH) it is the wedge that rests on the arched tourniquet, but on the outside of the latter.

In US patent 2 570 871 (SCHULZE) all the flexibility of the withers comes from the dimensions of the blade that constitutes it. On the other hand, the tourniquet does not present any particular stiffness in relation to any inclination of the rail. Finally, this tourniquet has no arc surrounding the wedge, so that it does not allow the accumulation of energy while minimizing tensions.

In the article PLASTICS IN JAPAN ”(PLASTICS N0 JAPAN) the tourniquet is made up of a substantially horizontal blade, one end of which rests on the rail and the other is curved to rest on the crosspiece, passing the wedge through that blade.

object of the present invention is to solve a new technical problem that consists of allowing simultaneously a certain number of services hereafter announced, that until now could not be reconciled, namely;

- use an unscrewed rail tourniquet to respond to the wishes of certain customers and for mechanization purposes.

- use a flat rail tourniquet to obtain a light spring that has a high frequency of its own and that can be supported, in particular, on the rail, thanks to an important surface, which minimizes pressure and wear. But the same principle can also be used

325 iSSS

60,451

Ref: Η 15204 Cas 4

03 / JBB / FRP principle, even to the same crosspiece with the same wedge, to use a round or square steel wire tourniquet, which is preferred by certain customers,

- the said rail can be installed by means of a simple translation parallel to the rail, to facilitate the laying operation and use a movement parallel to that of the laying train,

Mod. 71 - 10 OOO βχ - 4-87

- use a rigid wedge as a means of anchoring, the part of which is intended to hold the tourniquet in a deformed position will be substantially parallel to the rail; and this taking into account the inclination movements, that is to say, oscillation of the rail on its seat, which are rotations around an axis parallel to the axis of the rail. It is desirable that the tourniquet, designed to follow the rail elastically in order to continue in contact with the rail and press it against the respective base, has a rotation movement on itself that does not drag opposite antagonistic torque with it. Since the wedge has its part that holds the withers parallel to the rail, the two axes of rotation, respectively of the withers and the rail over itself, will be parallel,

- use a wedge that allows different sizes and types of tourniquets to be assembled, according to the desired effort and flexibility for that tourniquet and this on the same crosspiece without having to change the wedge,

- use a wedge that does not prevent any limit on the transverse length of the withers, length defined by the measure (taken perpendicular to the rail) outside the space occupied by the withers.

-460 ^ 51

Ref: Η. 15204 Cas 4

03 / JBB / FRP

Mod. 71 - 10 OOO βχ - 4-87

- use a wedge whose part resting on the tourniquet is inside a tourniquet, this tour or arch should be the tourniquet's main arch, that is to say, the one that accumulates the maximum placement deflection: this provision it has the advantage of being able to reconcile the fact that it has a highly flexible rail garrote (with a large arch) with the fact that it can be kept within the acceptable effort limits (the point of application of the effort exerted by the wedge on the tourniquet it is closer to the extreme tense fibers of the bow being inside it than outside) “This is not only an important advantage but also a specific feature in itself of the present invention. Indeed, it would be possible to imagine that a part of the wedge rested not on the inside of the arch but on the outside, as is the case in DE 1130461. However, in this case, the point of application of the effort (exerted by the wedge) on the tourniquet) in relation to the fibers more contracted in tension of the tourniquet arc and when doing this, the stresses in the tourniquet would be greatly increased. It was what was intended to be avoided in the present invention, the present invention also allows,

- obtain a fixing device which simultaneously presents:

elastic operation with respect to the upward and downward movements of the rail skate edge, in relation to the crosspiece.

the possibility of blocking an upward movement of the rail skate edge, if the amplitude of that movement exceeds a certain value. This is of paramount safety in relation to the inclination movements of the rail, which occur, in particular, in curves and when you want to be able to use under the rail a very flexible base to protect the crosspiece and the leveling—

-560 ^ 51

Aef: H. 15204Cas 4

03 / JBB / FRP solve this new technical problem

track.

invention allows co, for the first time and in a satisfactory way.

Thus, according to the invention, a device for fixing a rail to a crosspiece is provided, which consists of an elastic base between the rail and the crosspiece, a stop on each side of the rail skate, a wedge of each side of the rail and two tourniquets that rest on the rail skid and intended to cooperate with the wedges, each wedge comprising a branch parallel to the rail and creating a free space under that branch, characterized by the fact that the tourniquets are positioned transversely to the rail and have caMod. 71-10 000 ex -4-81 gives a clear theme to theirs, an arch, an outer part of which skates in a closed position, while one supports part of the arch to exert a clamping pressure of the rail, '' ¹ '''on and the force is introduced under that crack so that, a »

arch (6a, 6b) of the withers (5a 5b) branch (15) of the wedge (7) once the assembly is finished, completely

According to another particularly interesting feature, the tourniquet arch completely surrounds the wedge branch when the assembly is complete. According to another characteristic, the aforementioned arch has a substantially spiral shape when viewed from the top according to figure 1, defined below.

According to another variant, a spring tourniquet made of flat steel is used.

According to yet another variant, the flat steel used can be rolled and cut in place to optimize the stress distribution.

-660,451

Ref; Η. 15204 Cas 4

03 / JBB / FRP

According to an advantageous feature of the invention, the spring garrote used is made of an insulating material.

In addition to another advantageous feature, the spring garrote used ensures the lateral maintenance function of the rail thanks to a part that forms the stop.

According to an interesting variant of the invention, the spring tourniquet used is made of steel wire.

Mod. 71 - 10,000 βχ - 4-07

Still according to another variant, the aforementioned wedge has an entry chamfer, used to facilitate the placement of the tourniquet spring.

According to a feature of the invention, the wedge branch is located outside the space between the skids of the rails, parallel to the latter.

According to another feature of the invention, the inner end of the aforementioned arc rests on said arc, close to its inner end.

According to a variant of the invention, the tourniquet consists of a single thread comprising two arches connected together by an incurved connecting part in the direction of the rail defining the aforementioned internal end, forcibly introduced under the wedge branch.

According to a particularly interesting feature of the invention, the aforementioned tourniquet consists of a single plate or lamella, one end of which has a substantially spiral shape.

-6-4

25. O12S3

6OJ45I

Ref: H. 15204 Cas 4

03 / JBB / FRP

According to a variant, the tourniquet is electrically isolated from the rail skid and comprises at least one insulating part that forms a side stop and a part of which is interposed between the arch and, at the level of the rail skid area

According to the rear side and support stop for the

According to the fixation route

According to pressure with another variant of embodiment, the comprises a part which extends so that at the end it forms a shoulder at the rear end of the withers.

with a characteristic of the invention, the garé as previously defined.

Mod. 71 - 10 000 ex - +87 With another characteristic of the invention, the fixation wedge is as previously defined.

According to the present invention, the tourniquet is designed so that it does not present any antagonistic torque at the level of the connection with its wedge.

Thus, a rotational movement of the rail in relation to its longitudinal axis, ramento at the level of the contact does not translate to an interior of the arch with te of the wedge shape that keeps it withers according to the general perpendicularly oriented the present invention has emper_ a pa_r one to the rail, more precisely a flat spiral shape that is inscribed on a plane perpendicular to the rail. The flexing work during the placement, as well as later in dynamic operation, is also done in a plane perpendicular to the rail, like the spiral was designed to be able to block beyond a certain inclination of the rail,

-760.-4 51

Ref; Η. 15204 Cas 4

03 / JBB / FRP

elevation value. This was not only not foreseen, but it is even impossible with the garrotes of the prior art.

On the other hand, according to the invention, the part of the wedge that serves to retain the tourniquet, is completely surrounded by the tourniquet arch once it is assembled and the active part of the wedge, parallel to the rail, disappears inside the arch when the assembly.

In addition, the present invention relates to a 3-point tourniquet, that is, which comprises a support reaction on the rail, a support reaction on the cross member and a maintenance force applied within the arch.

Mod. 71 - 10,000 βχ - 4-87

Other objectives, characteristics and advantages will clearly stand out, in the light of the following explanatory description, made with reference to the accompanying drawings, which represents a currently preferred embodiment of the present invention, given simply by way of example and which therefore should not in any way. to limit the scope of the present invention.

In the drawings:

figure 1 is a top view of a rail fastening that benefits from the present invention.

figure 2 is a top view of figure 1, figure 3 θ is a perspective view of the upper part of the wedge usually fixed permanently to the upper part of the crosspiece or saddle (the words anchor hooks are three synonyms here),

-860.4.51

Ref: Η. 15204 Cas 4

03 / JBB / FRP

- figure 4 is a diagram showing the collocation deflection of the spring tourniquet,

- figure 5 ® is a perspective view of an embodiment of the flat tourniquet,

figure 6 is a perspective view of an embodiment of the round steel tourniquet.

With reference to figures 1 to 5, the rail fastening device on a crosspiece comprises an elastic base (2) between the rail and the crosspiece, a stop (3) on each side of the rail (4), a wedge (7) of each of the rail modes and two tourniquets (5a, 5b) that rest on the rail (4) of the rail and intended to cooperate with the wedges (7), each wedge comprising a branch ( 15) parallel to the rail creating a free space (16) in said branch (15), characterized in that the tourniquets (5a, 5b) are positioned transversely relative to the rail and have, each one, an arc (6a , 6b), that an external part (30, 70) rests on the skid (4) in the clamping position, while an internal part (32, 72) of the arch is forcibly introduced under said branch (15 ) of the wedge to exert a clamping pressure on the rail skid.

According to an advantageous embodiment, the branch (15) of the wedge (7) is located outside the space between the skids of the rails, parallel to the latter.

The remaining part of the wedge (7), possibly in the form of an elbow at (14) to make it more rigid, is arranged outside the inner space of the withers (5 ^a , 5b) according to a clearly visible embodiment in figure 3.

-96θΛ51

Hef: H. 1J2O ^ Cas k

03 / JBB / FKP

It is observed that the active part of the wedge (7) is constituted by the branch (lp) which is arranged parallel to the rail.

According to a particular characteristic, the inner end (32) of the bow (6a, 6b) is located on the rail, the (6a, 6b) on the edge of the branch skid (15) is advantageously supported on the arc near its inner end (32).

Mod. 71 * 10 000 «x - 4-87

In figure 1, the tourniquet (5a) is located on the right side of the rail before the assembly and on the left, the tourniquet (5b) mounted, that is, tightening the rail skid (U), at the level of the zone (10). Between the rail skid (^ l ·) and the support table (9) of the crosspiece (1) there is an elastic base (2). Between the two tourniquets, unmounted (5a) and mounted (5b), the difference lies essentially in the curvature of the arch which is reduced to pass from the profile (6a) to the profile (6b).

bow is kept deformed and flexed thanks to the part (11) of the branch (15) of the wedge (7), itself sealed or anchored in a way that is, in principle, immovable, to the crosspiece (1). The wedge (7) can also be an integral part of the rail support, namely when that support is a metallic saddle (the metallic saddle can be used, if necessary, in indirect seating with all types of wooden, metal and even of concrete).

When the tourniquet (5 = ¹ ) is tightened on the wedge (7) in its final position, the bow (6b) completely surrounds the branch (15) of the wedge, relative to its profile.

stop (3) serves for the lateral maintenance of the rail.

It can either pre-exist on the platter before the installation of the tourniquet, or come with the latter (glued or a-10

00,451

Ref: H. 15204 Cas 4

03 / JBB / FRP

the latter or forming an integral part of the respective structure). Preferably, the stop (3) is made of a plastic material.

Mod. 71 - 10,000 βχ - 4-87

In (8), there is a small support plate for the withers. This plate (8) does not allow the garrote material to rest directly on the crosspiece (1) and precisely locate the rear support. This plate (8) can be glued or tightened on the withers (5b) or already exists on the cross member 1. It can also be replaced by a localized shoulder of the cross member (1), if direct contact between the cross member (1) and the tourniquet (5b). This plate (8) can also be attached to the stop (3) and this to limit the number of components; for this purpose, either a very large stop (3) (measured perpendicular to the rail) will be used, or a stop (3) with a tongue that comes up on the crosspiece will constitute the support (8) at its end.

The plate (8), in addition to its rear support function for the withers (5a, 5b), can also serve immobilization in rotation of the withers (flat rotation along an axis perpendicular to the support table (9) of the rail); in this case, the plate (8) must cooperate with a protrusion or emptying of the crosspiece (1).

If an insulating installation is desired to prevent leakage of current from one rail to another, or between the rail and the ground, it is necessary;

are of insulating quality and an insulating insert is inserted between the tourniquet (5a) θ θ darril skid (4), at the level of the outer part (.30) of the arch (6a, 6b) that rests on the skid of the rail (4) at the level of the pressure zone (10) or that the wedge (7) is, itself / iso-11 <0.451

Ref: Η. 15204 Cas 4

3 / jBB / FRP

before.

If the insertion of an insert between the arch (6b) and the rail track (4) at the level of the external supporting part (30) is chosen, it is also possible to ensure that this insulating insert is connected to the stop ( 3) to constitute a single and single monobloc insulating assembly.

- A solution for the tourniquet also, the base 1 before.

consists of resorting (5b) and, in this case, (2) and the stop (3) to a sufficient isolating material that,

Mod. 71 - 10 OOO βχ - 4-87

Figure 2 shows the assembly in a top elevation view. On the right side, the tourniquet (5a) is in a free position, that is, prior to assembly. It can be seen in this figure, on the left side, that the tourniquet arch, once assembled, masks branch 15 of wedge 7 in great art, passing over that branch 15.

This figure also shows that the placement of the withers by means of translation parallel to the rail can also be planned to be carried out until it is leaning against any vertical part of the wedge 7,

Figure 3 θ is a perspective view of the upper part of the wedge (7). The wedge is a rigid piece and, in principle, cannot be disassembled, that is to say it has been sealed, glued or welded to the crosspiece or saddle. The branch (15) θ roughly parallel to the rail. The lower part (11) of the branch (15) is designed to rest on the withers within the arch (6b). A free space (16) exists under the rim (11) to allow the placement of the withers.

The part (12) is a non-return post, which prevents

-1260.4-51

Ref: II. 15204 Cas 4

03 / JBB / FRP

Mod. 71 - 10,000 βχ - 4-87

(

after assembly the tourniquet can come out by itself, thanks to longitudinal displacements. The leveling between (11) and (12) is reduced to the necessary strictness, for example 2 to 3 mm, so as not to increase the tourniquet flexion. Once the entire end of the arc has passed this obstacle, the a_rco's end will rise again elasticly and stick to the edge (11; of the wedge.

The part (13) is an entry chamfer; it is not essential but it facilitates the placement of the withers. In the absence of a correctly dimensioned chamfer (13), it is necessary, when assembling the tourniquet with respect to the wedge, to exert vertical downward effort on the arch (6a) and release this effort, as soon as the tourniquet is at least partially fitted under the part (12).

The elbow shape (14) of the wedge is given here as an indication, to reinforce said wedge. Preferably there are two wedges for each crosshead, ie four for each crosshead. The two wedges of the same crosshead, that is to say, belonging to the same rail, can be arranged symmetrically in relation to the axis of the support table (9) of the rail or in relation to the center of that same support table.

Figure 4 shows the tourniquet, before (6a) and after (6b) the assembly. For simplicity, the tourniquet was assimilated to its neutral fiber as if it had no thickness. Deflection is measured in the arc at the point of application of the part (11) of the wedge. The greater the deflection, the more the tourniquet will exert an important force on the rail, by reaction, and the rail will also be more elastic.

-1360,451

Ref; Η. 15204 Cas 4

3 / jBB / FRP

Mod. 71 - 10,000 βχ - 4-87

The game J between the lower part of the arch (6b) and the upper part of the part (50b) of the withers, will be obtained through the appropriate dimensioning of the withers. It is chosen according to the lifting stroke that is accepted for the rail. Beyond a lift of J mm from the edge of the rail skid (4) the part (50b) of the withers comes into contact with the underside of the part (60b) of the arch. This part (60b), because it is itself retained by the part (11) of the rigid wedge (7), causes the rail movement to block.

R and F are two consecutive reactions to action Q, itself generated by reflection. F is the forward reaction designed to provide the clamping force of the rail (at the level of the pressure zone (10) of the part (30) of the withers on the rail (4), according to figure 1).

R is the back support reaction (located on the plate (8) in figure 1).

The part of the withers located between the application areas of reactions R and F can be straight or slightly pumped. When placing the withers, yours. The shape therefore changes slightly, so that the elastic energy is essentially accumulated by the arc (6b).

The inner end (32) of the bow (6a, 6b) can advantageously have a slight hollow (60a, 60b) to precisely position the tourniquet relative to the rail.

Figure 5 is an embodiment of the tourniquet in flat laminated steel, in order to optimize the stresses in the tourniquet arc. End cutouts can also be predicted, in the image of what is generally done to

-14OO.Upl

Ref: H. 1520 ^ Cas h

03 / JBB / FRP

the ends of the leaf springs of the truck suspensions, that is to say, a tourniquet (pa, 5b) whose part (6a, 6b) is less than the width of the support part on the rail through zone 10 .

Mod. 71 - 10,000 ex - 4-87

Figure 6 shows, by way of example, a possibility of carrying out the present invention with a tourniquet made of wire instead of flat steel.

The tourniquet (5a) θ then consists of a single wire (5a, 5a) that comprises two arches (6a) connected together by a connecting part (72) curved in the direction of the rail that defines the previously mentioned inner end, introduced forcefully under the branch (lp) there is a wedge (7).

This tourniquet then rests on the rail skid by means of two zones (7θ) located at the beginning of the arch (6a) similarly to the tourniquet (5a, 6a) of figures 1 to 5.

In this case, the material of the tourniquet is preferably steel. The principle and shape of the wedge, as well as the principle of assembly, remain the same. For this wire tourniquet, localized flattening can also be practiced.

the present invention simultaneously covers the fixing assembly as a rail maintenance device on a crosspiece, the withers and the wedge as new industrial products.

The first application for the invention described above was filed in France on 27 November 1987 under the N '. 87.16525.

Claims (12)

- CLAIMS Mod. 71 - 10,000 βχ - 4-Θ7 1-. - Device for fixing a rail on a crosspiece, which has an elastic support (2) between the rail and the crosspiece, a stop (3) on each side of the rail (4) on the rail and a wedge (7) on each side of the rail. rail and two withers (5 ^a , 5b) which rest on the rail (4) of the rail and intended to cooperate with the wedges (7) comprising each of the wedges a branch (15) parallel to the rail and creating a space free (16) underneath said branch (15) characterized by the fact that the withers (5 ^a , 5t>) are positioned transversely in relation to the rail and each have an arc (6a, 6b), the part of which outer (30, 70) rests on the skid (4) in a closed position, while an inner part (32, 72) of the arch, to exert a tightening pressure on the rail skid, is forcibly inserted from below said branch (15) of the wedge, so that, once the mounting arch (6a, 6b) of the withers ^(a · 5, 5b) completely surrounds the branch ( 15) of the wedge (7). 2?. Fixing device according to claim 1, characterized in that the arch (6a, 6b) of the tourniquet has a substantially spiral shape, when viewed from the top, according to figure 1 3-. - fixing device according to the indications reivin 1 to 2, characterized in that the spring-tourniquet (5a) is used held in flat steel. 4 ?. Clamping device according to claim 3, characterized in that the flat steel uses the power to be laminated and cut locally to improve the distribution of efforts. -1660,451 Ref: 'ί. 15204 Cas 4 03 / jBB / FRP 5®. - Fixing device according to claims 1 to 2, characterized in that the tourniquet (spring 5 ^a ) used is made of an insulating material, 6 ^a . Fixing device according to claim 5, characterized in that the garrote-spring (5a) used ensures the lateral maintenance function of the rail, thanks to a part of itself that forms the stop (3). - Fixing device according to claims 1 to 2, characterized in that the garrote-spring (5 ^a ) used is made of steel wire. Mod. 71 - 10,000 βχ - 4-87 8? Clamping device according to any one of claims 3 ^to 7, characterized in that the wedge has an entry chamfer (13) used to facilitate the placement of the tourniquet spring. Clamping device according to any one of claims 1 to 8, characterized in that the branch (15) of the wedge is located outside the projection of the rail (4), parallel to the latter. 10? «- Clamping device according to any one of claims 1 to 9, characterized in that the inner end of the arch is located substantially at the level of the rail skate edge, supporting the above-mentioned branch (15 ) on said arc, in the vicinity of its internal end. 11 ?. Fixing device according to any one of claims 1 to 10, characterized in that -176c.451 Ref: H. 1.5204 Cas 4 03 / JBP / FRP the tourniquet consists of a single thread that comprises two arches connected together by a curved connecting part in the direction of the rail, defining the referred internal end, forcibly introduced under the branch (15) of the wedge. 12 ?. Fixing device according to claims 1 to 6, or claims 8 to 10, characterized in that the withers consist of a single plate or lamella, having a substantially spiral-shaped end. Mod. 71 - 10,000 βχ - 4-87 13 ?. Fixing device according to any one of claims 3 to 7, characterized in that the tourniquet is electrically isolated from the rail skid and comprises at least one insulating part that forms a lateral barrier (3) and of which a part it comes between the support part (3θ) of the withers and the skate (4), at the level of the pressure zone (10). 14 ?. Fixing device according to any one of claims 3 to 7, characterized in that the side stop (3) comprises a part which extends towards the rear and which forms at its end a supporting shoulder 8 of the rear end of the withers ( 5a).