Adjustable wrench with improved mechanical stability
Patent Information
- Application Number
- FR2023000938
- Authority / Receiving Office
- FR · FR
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2023-02-01
- Publication Date
- 2025-03-07
- Estimated Expiration
- 2043-02-01
Smart Images
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Abstract
Description
Title of the invention: ADJUSTABLE WRENCH WITH IMPROVED MECHANICAL STABILITY TECHNICAL FIELD OF THE INVENTION
[0001] The invention relates to an adjustable wrench, comprising a wheel provided for driving a jaw by means of a rack. TECHNOLOGICAL BACKGROUND
[0002] An adjustable wrench is a tool for tightening and loosening nuts. As illustrated in [Fig.l], a conventional adjustable wrench 100 typically comprises a handle 120 and a head 130. The head 130 comprises a fixed jaw 140 secured to the handle 120 and a movable jaw 150 secured to a rack 155 moved relative to the fixed jaw by means of an adjustment wheel 160 consisting of a worm screw mounted around an axis 165 in an opening 132 located in the head 130. Moving the movable jaw makes it possible to define a space between the two jaws corresponding to the distance separating two opposite faces of a nut 170.
[0003] One cause of deterioration of bolt edges is related to the way in which adjustable wrenches are used. For example, tightening a bolt requires opening the space between the jaws sufficiently with the wheel, engaging the wrench around the bolt, bringing the jaws together so as to grip the bolt at two of its opposite faces, turning the wrench in one tightening direction, then, in the most frequent case, reopening the jaws to disengage the wrench and turning it in the opposite direction to the tightening direction, then repeating the above steps. The repetitive nature of the operation sometimes leads to the bolt not being properly gripped between the jaws using the wheel. An approximate adjustment of the spacing between the jaws or a progressive slippage of the movable jaw causes wear of the edges of the bolt, which can lead to its deterioration to the point where it becomes necessary to replace it.
[0004] Indeed, for the reasons mentioned above, repeated tightening and loosening of the bolt tends to round off its edges until it no longer allows tightening at a sufficient torque or makes tightening or loosening difficult, in which case it is generally necessary to replace the bolt.
[0005] In order to prevent damage to bolts, improvements have been suggested to improve conventional adjustable wrenches, as disclosed for example in documents CA2567082A1 or EP1000708A1.
[0006] However, a solution that is satisfactory from a practical point of view still remains to be implemented. Statement of the invention
[0007] An object of the invention is to provide an adjustable wrench preventing the deterioration of bolts occurring during their repeated tightening and loosening.
[0008] With a view to achieving this aim, a first aspect of the invention is an adjustable wrench comprising an actuating rod on which is mounted a head comprising a fixed jaw and a movable jaw, the movable jaw is secured to a rack comprising teeth separated by tooth bases, the adjustable wrench further comprises a wheel provided with a thread meshing between the teeth of the rack, the tooth bases each having a concave profile capable of receiving the thread of the wheel.
[0009] An advantage of the structure according to the invention is the provision of an adjustable wrench with improved mechanical stability by the structure of the rack engaging with the wheel. The wheel ensures the movement and holding of this rack and therefore of the movable jaw of the wrench. The precision of the movement and the stability of the holding depend on the facing surfaces of a thread of the wheel and teeth of the rack. In the wrench according to the invention, with a particular geometry of the rack, the facing surfaces are, for given dimensions of the rack and the wheel, relatively larger than in the case of a conventional geometry. Thus, all other things being equal, the rack and therefore the jaw attached thereto are held more stably by the wheel, with a limited risk of slippage, than for a conventional adjustable wrench.
[0010] According to additional non-limiting characteristics of the first aspect of the invention, considered individually or in any technically feasible combination: - the concave profile of the tooth bases can be defined by an arc of a circle; - the arc of a circle can have a radius of curvature greater than or equal to half of the outside diameter of the thread of the wheel; - the teeth may each have a concave profile summit; - the concave profile of the tooth tops can be defined by an arc of a circle; - the arc of a circle can have a radius of curvature greater than or equal to half of the inner diameter of the thread of the wheel; - the teeth of the rack can extend in a direction inclined at an angle of between 2° and 20° relative to a plane perpendicular to an axial direction of a rod of the rack; - surfaces of the rack and surfaces of the wheel intended to come into contact with each other may have complementary geometries; - surfaces of the rack and the wheel intended to come into contact may have helical geometries; - a mechanical clearance of between 0.02 mm and 0.2 mm may be provided between the surfaces of the rack and the wheel intended to come into contact; - the fixed jaw being integral with the actuating rod in a rotatable manner around an axis of rotation, the actuating rod may comprise an element provided to block a longitudinal movement of the wheel when a torque is exerted on the actuating rod in a tightening direction; - the adjustable wrench may comprise a plate mounted coaxially with the wheel, interposed between the wheel and the element intended to block the wheel when the wrench is turned in a tightening direction, the plate being able to comprise at least one notch configured to allow said element to pass through, intended to block the wheel when the wrench is turned in a direction opposite to the tightening direction while a fixed object is engaged by the fixed jaw and the movable jaw; - the plate may further comprise a concavity configured to accommodate a rod of the rack; - the adjustable wrench may comprise a torsion spring mounted around the axis of rotation and exerting a force on the actuating rod and the fixed jaw tending to close a space between one end of the actuating rod and the fixed jaw; and - the adjustable wrench may comprise a second return means exerting on the wheel a force tending to bring the movable jaw closer to the fixed jaw.
[0011] The combination of the adjustable wrench with a ratchet system is particularly advantageous in that the tightening operation requires only a single adjustment of the spacing between the jaws of the wrench, the ratchet system avoiding successive disengagements and re-engagements of the wrench around the bolt, a spacing which can be precisely maintained throughout a tightening operation despite repeated steps of rotating the wrench in the tightening direction and rotating in the opposite direction until an adequate tightening torque is obtained. Conversely, in a conventional wheel-rack system, the movable jaw may have a tendency to slip during these repeated operations, leading to damage to the nut as described above. BRIEF DESCRIPTION OF THE FIGURES
[0012] Other characteristics and advantages of the invention will emerge from the detailed description of the invention which follows with reference to the appended figures in which:
[0013] [Fig.l] [Fig.l] represents a conventional adjustable wrench;
[0014] [Fig.2] [Fig.2] shows a perspective view of a ratcheting adjustable wrench according to the invention in an orthogonal xyz reference frame;
[0015] [Fig.3] [Fig.3] represents an exploded view of the key of [Fig.2] in the yz plane;
[0016] [Fig.4] [Fig.4] represents a perspective view of the fork of the key of [Fig.2];
[0017] [Fig.5] [Fig.5] represents a view of the fixed jaw of the key of [Fig.2] in the xz plane.
[0018] [Fig.6] [Fig.6] illustrates the operation of the key of [Fig.2];
[0019] [Fig.7] [Fig.7] represents a perspective view of the rack and the movable moss of the key of [Fig.2];
[0020] [Fig.8] [Fig.8] represents a perspective view of the plate of [Fig.2];
[0021] [Fig.9] [Fig.9] represents two variants of the rack of [Fig.7] in the xz plane;
[0022] [Fig. 10] [Fig. 10] illustrates a rack of the key of [Fig.2] in the xy plane;
[0023] [Fig. 11] [Fig. 11] illustrates a comparison between the rack of a key according to the invention and a conventional rack;
[0024] [Fig. 12] [Fig. 10] represents the wheel of the key illustrated by [Fig.2];
[0025] [Fig. 13] [Fig. 13] illustrates a variant for the rack and wheel geometries of [Fig.2];
[0026] [Fig. 14] [Fig. 14] illustrates a stud of the key illustrated by [Fig.2]; and
[0027] [Fig. 15] [Fig. 15] illustrates a torsion spring of the key illustrated by [Fig.2]. DETAILED DESCRIPTION OF THE INVENTION
[0028] Figures 2 to 15 illustrate a particular application consisting of a ratchet wrench with improved mechanical stability, making it possible to exploit the advantages of the invention to the best advantage. [Fig.2] is a perspective representation in an orthogonal space defined by the three axes x, y and z defining, in this order, a direct trihedron, as well as planes xy, yz and zy, respectively by means of the axes x and y, y and z, and z and x. These axes are reused in the other figures to orient the elements illustrated in the space of [Fig.2].
[0029] Figures 2 to 10 and 12 to 14 illustrate a ratchet wrench 200 according to the invention and its elements, as well as its mode of operation. [Fig. 11] illustrates a comparison with a conventional adjustable wrench.
[0030] The wrench 200 comprises an actuating rod 220 on which a head 230 is mounted. The rod is configured to accommodate a handle capable of exerting a given tightening torque so as to form with the wrench 200 a torque wrench. Alternatively, the rod 220 could itself form a handle such as the jaw 120 of the conventional adjustable wrench 100.
[0031] The head 230 comprises a fixed jaw 240 and a movable jaw 250 which is secured to a rack 255 comprising a rack rod 256. The rod 256 is provided with teeth 257 and tooth bases 257b located between two teeth of the rack or of the outer side of the first or last teeth of the rack. The teeth 257 have tooth apices 257s located opposite the movable jaw 250 relative to the rod 256. The assembly formed by the movable jaw and the rack is reversible, that is to say that it can be turned 180° to use one or other of the faces of the jaw 250, each adapted to a particular type of object to be gripped, for example a nut having parallel faces or a pipe of circular profile.
[0032] The fixed jaw 240 extends into a tab 241 defining an opening 242 and a first housing 243 provided to accommodate the rack rod 256.
[0033] The opening 242 is provided to accommodate a wheel 260 mounted in rotation around a first wheel stud 262 inserted in a second housing 244 along an axis 265 parallel to a direction DI of movement of the rack 255 and the movable jaw 250. The wheel 260 is mounted around the first stud 262, the wheel being provided with a thread 261 meshing between the teeth 257 of the rack so as to control the position thereof. More specifically, flanks of the thread 261 are opposite flanks of the teeth 257, the flanks of the thread coming into mechanical contact with the flanks of the teeth to move the rack (a flank of the thread pushes the flanks of the teeth in a direction of movement) or maintain its position (a flank of the thread blocks the teeth and therefore the rack).A spring 264 and a plate 263 are also mounted around the first stud 262, so that the spring 264 applies a force to the wheel 260 via the plate 263, this force tending to bring the movable jaw 250 closer to the fixed jaw 240.
[0034] The actuating rod 220 extends at a head end 224 formed by two parallel extensions 224A and 224B in the form of parallel forks configured to accommodate between them the tongue 251 of the fixed jaw 240. Each of the parallel extensions 224A and 224B comprises a recess 226 between two opposite branches of the corresponding fork, branches Ai and A2 for the extension 224A and branches Bi and B2 for the extension 224B, and configured to accommodate the wheel 260 and guarantee access thereto for manual adjustment of the position of the rack 255.
[0035] In order to obtain a ratchet mechanism, the head end 224 and the fixed jaw 240 are mounted in rotation relative to each other about a common axis 210 by means of a second stud (not shown) passing through corresponding circular openings 225A and 225B in the two extensions 224A and 224B at the branches Ai and BH respectively, and a circular opening 246 in the tongue 241.
[0036] [Fig.6] illustrates an operation of tightening a nut using the ratchet of the key 200. For reasons of clarity, the rack rod 256 is not shown here.
[0037] In state (A), the position of the movable jaw 250 has been adjusted by means of the wheel 260 in such a way that the jaws 240 and 250 are adjusted around two opposite faces of a bolt 270. Thus, the jaws can no longer come closer together. A torque is applied to the bolt in the tightening direction DI via the actuating rod 220. As a result, contact zones C located outside the branches A2 and B2 of the fork 224 (see [Fig. 4]) are held in abutment against contact zones C2 of the extension tab 241 of the fixed jaw 240. In this position, the internal faces FA and FB of the branches A2 and B2, respectively, prevent the wheel from moving away longitudinally from the axis 210 in the direction D4 parallel to the axis 265. The wheel 260 is thus blocked longitudinally via the plate 263.
[0038] State (B) illustrates the situation where, with the nut remaining engaged by the jaws, i.e. in contact with each of the two jaws, the wrench is turned in the direction D3 opposite to the tightening direction D2 by applying a torque in this direction D3. This corresponds to the action of turning the wrench in a loosening direction in order to repeat the tightening action when, for example, there is not enough space to make complete turns of the wrench around the bolt. Here, the head end 224 pivots around the axis 210, opening a gap between the head 224 of the actuating rod 220 and the fixed jaw 240, releasing the plate 263 and the wheel 260 which, under a reciprocal force exerted by the bolt 270 on the movable jaw 250, is pushed in the direction D4, away from the axis 210. At the same time, a gap Esp located between the head end 224 of the actuating rod 220 and the fixed jaw 250 opens.Thus, the jaw 240 is released and the key 200 can be turned in the opposite direction to the tightening direction without disengaging the bolt from between the jaws and without applying significant torque to it, which could unscrew it.
[0039] In this way, we find the operation of a flat ratchet wrench, applied to an adjustable wrench whose distance between the jaws is automatically varied only in a loosening rotation direction by action on the actuating rod 220. In the opposite tightening rotation direction, the distance is maintained, as when trying to screw an object such as a bolt onto a threaded rod.
[0040] [Fig. 8] shows the plate 263 in detail. It is designed so as to improve the reliability of the system for controlling the movement of the wheel 260 while improving the compactness of the assembly consisting of the wheel 260, the plate 263 and the first stud 262, and thereby the compactness of the assembly of the head 230 of the key 200.
[0041] The plate 263 includes two symmetrical lateral notches 263A and 263B intended to be located on the side of the head end 224 of the actuating rod 224A, so as to facilitate the passage of the branches A2 and B2 in the direction D4 beyond the plate 263, as illustrated in (B) of [Fig. 6]. This characteristic makes it possible to reduce the amplitude of rotation necessary to release the plate 263 and the wheel 260, facilitating the use of the key 200.
[0042] The plate 263 also includes a concavity 263C intended to accommodate the rod 256 of the rack 255. The notches 263A and 263B and the concavity 263C allow the plate 263 to occupy a maximum surface area in the volume of the opening 242 in a plane perpendicular to the axis 265 of the wheel, while ensuring the functionality of the key, which improves the reliability of the latter: the internal faces FA and Fb of the branches A2 and B2 intended to hold the wheel by means of the plate 263 are ensured to come into contact with the latter thanks to the large surface area that it occupies in the opening 242, only reduced by the notches 263A and 263B and the concavity 263C.
[0043] [Fig.7] illustrates the assembly formed by the movable jaw 250 and the rack 255 according to a perspective view.
[0044] [Fig.9] illustrates two variants (VA) and (VB) of this set, seen in the xz plane, and which are distinguished by the geometry of the rack, and more specifically by the geometries of the 257 teeth. These geometries provide advantages to the use of the key as explained below.
[0045] In the variant (VA), the bases 257b of teeth located between two teeth, or in front of the first tooth of a rack, have a concave profile in a direction parallel to the tops of the teeth, capable of receiving the thread 261 of the wheel 260. Such a profile allows the thread 261 of the wheel to engage the teeth over a relatively large height and a relatively large width at the level of each tooth, which makes it possible to increase the contact surface between a flank of the thread 261 and the flanks of the teeth 257 and improves the driving and holding of the rack by the wheel. The concave profile can for example be defined by an arc of a circle, possibly having a radius of curvature greater than or equal to the outer radius of the thread 261, i.e. 0ext / 2 where 0ext represents the outer diameter of the thread 261 as illustrated in [Fig. 12].
[0046] In the variant (VB), in addition to tooth bases similar to those of the variant (VA) with the associated advantages, the tops of the teeth 257 also have a concave profile, which can for example be defined by an arc of a circle, possibly having a radius of curvature greater than or equal to the internal radius of the thread 261, i.e. 0 int / 2 where 0 int represents the internal diameter of the thread 261 as illustrated by [Fig. 12]. With such a geometry, the wheel and the rack have large facing surfaces, which ensures great stability between these parts, with little mechanical play and a reduction in vibrations compared to conventional adjustable wrenches.
[0047] [Fig. 11] illustrates the above advantages by a comparison between (A) the variant (VB) described above and (B) a conventional geometry distinct from the variant (VB) in that the teeth 257' and the rod 256' of this conventional rack have flat profiles for the tooth tips and the tooth bases. The profiles P ext and Pint represented by circles in dotted lines respectively indicate the projections of the outer diameter and the inner diameter of the thread of the wheel 260 parallel to the axis 265 on a plane perpendicular to this axis. The profiles Pext and Pint make it possible to visualize the meshing of the thread 261 between the teeth 257 of the rack 255.
[0048] [Fig. 11] thus illustrates by the hatched surfaces R and R' the overlaps between the lateral surfaces of the threads and the teeth, which correspond to the intersection surfaces of the profile Pext with the teeth 257 and 257'. The fact that the surface R is greater than the surface R' indicates a greater overlap in the geometry according to the invention, favoring better control of the position of the rack 255 and therefore of the movable jaw 250 compared to the conventional geometry.
[0049] Furthermore, it can be seen that in the case of the geometry of the rack according to the invention, the profiles Pint and Pext follow the profiles of the tooth heads and the tooth bases, and this for each tooth and each tooth base over the length of the rack rod, ensuring involuntary relative movements between the rack and the wheel of very small amplitudes whatever the direction of movement considered, ensuring the stability of the rack. Conversely, in the conventional geometry illustrated in (B), only a point contact is observed in the plane of the figure, insufficient to ensure the stability of the relative positioning of the rack and therefore of the jaw 250, for example in the case of a rotation Rot around this point contact in the plane of the figure.
[0050] The above remarks concerning variant (VB) also apply to variant (VA).
[0051] Another advantage of the rack is explained by means of [Fig. 10], which illustrates the rack seen in the xy plane, giving a view of the top of the teeth 257, which each extend in a plane defined by (i) a direction perpendicular to the direction 256d of extension (or axial) of the rod 256 and opposite the jaw 250 and (ii) a direction 257d inclined at an angle a between 2° and 20° relative to a plane perpendicular (axis zx) to the direction of extension 256d of the rack rod 256. In this configuration, the flanks of the teeth belong to planes. The profiles mentioned in the preceding paragraphs are to be considered in planes each perpendicular to the plane of the figure and including the direction 257d. In other words, the profiles are to be considered in planes substantially parallel to the planes of extension of the teeth.
[0052] The angle a is chosen so that the flanks of the teeth follow as closely as possible the flanks of the thread 261 of the wheel, that is to say that they are substantially parallel to the flanks of the thread 261, and in particular parallel to a tangent to a flank of the thread at point D of the thread located on the side of the rack and belonging to a plane of symmetry Sym of the rack 255. When the flanks of the thread are defined for example by a helicoid with an axis corresponding to the axis 265 of the wheel, the angle a corresponds to the angle that a tangent Tg makes to this helicoid with respect to a normal direction Nor to the axis 265 in a normal projection on a plane containing this axis, as illustrated by [Fig. 12], this figure representing such a projection in the yz plane.
[0053] The angle a of inclination of the direction 257d ensures a strong proximity between the flanks of the teeth and those of the thread, which limits the play between the wheel and the rack and has the advantage of reducing vibrations and sliding between these parts, making the use of the key easier and more comfortable.
[0054] Figures 9 to 11 and their descriptions apply, among other things, to teeth 257 having flat or any flanks in contact with a flank of the thread 261. An improvement consists in using, for the parts of the rack facing the corresponding parts of the wheel, a geometry complementary to that of these corresponding parts, as illustrated by [Fig. 13]. Complementary geometry of the rack with respect to the geometry of the wheel is understood to mean a geometry defining a volume of the rack as a subtraction of the volume of the wheel from a full volume. This can be done, for example, at the stage of defining the shapes of the rack in software for designing three-dimensional mechanical parts by a Boolean operation of subtraction of shapes.In this way, a surface contact geometry can be obtained between (1) the flanks 257f of the teeth 257 of the rack and the flanks 26If of the thread 261 of the wheel, (2) the tooth apices 257s and the base 261b of the thread of the rack and (3) the tooth bases 257b and the apex 261s of the thread of the rack. Thus, in this configuration, the flanks of the teeth of the rack are not planar but form a surface complementary to that of the flanks of the thread of the wheel, and follow for example the geometry of a helicoid.
[0055] In practice, for production, assembly and use, a clearance J of between 0.02 mm and 0.2 mm is maintained between these surfaces by adjusting the dimensions in order to limit friction and possibly leave a free space for a lubricant. Thus, the amplitudes of the vibrations and the relative movements of the rack and the wheel are limited by the clearance J.
[0056] In this surface contact geometry, despite the play, during the blocking or movement of the rack imposed by the rotation of the wheel, there will be a surface contact between a flank of the thread and a flank opposite the teeth of the rack. It can always be considered that the teeth generally extend in the direction 257d illustrated by [Fig. 10], even if the flanks can no longer be strictly considered as planes.
[0057] Such a geometry makes it possible to reduce vibrations and relative movements between the wheel and the rack, facilitating the use of the key and improving its comfort of use. Its resistance to wear is also improved since the forces are distributed over a large contact surface rather than being concentrated at point contact zones.
[0058] [Fig. 14] illustrates a stud 280 having a head 282 of a first diameter at a first end, a first cylindrical section 286 at an end opposite that of the head, and a second cylindrical section 284 between the head 282 and the first cylindrical section 286. A diameter of the second cylindrical section is strictly greater than a diameter of the first cylindrical section. This stud is intended to slide along its axis in a circular opening 228 and take either a raised position or a pushed-in position.
[0059] In the raised position, the first cylindrical section 286 is located in an extension plane of the tongue 241 and does not interfere with it when the actuating rod 220 pivots along the axis 210 as illustrated in (B) of [Fig.6], the actuating rod 220 and the fixed jaw 240 can then pivot around each other. In this situation, the key can be used as a ratchet key.
[0060] In the depressed position, it is the second cylindrical section, of larger diameter than the first cylindrical section, which is located in the extension plane of the tongue 241. The tongue and the second cylindrical section are designed to come into abutment against each other at a shoulder 245 of the tongue, so as to maintain the actuating rod 220 and the fixed jaw 240 in the same relative position. In this situation, the wrench can be used as a conventional wrench without a ratchet, such as the wrench illustrated in [Fig. 1], that is to say that this wrench can be used both for tightening and for loosening a bolt. The stud 280 constitutes a locking means for the adjustable wrench 200, configured to block the rotation between the actuating rod 220 and the fixed jaw 240 according to the user's wishes, in a reversible manner.
[0061] [Fig. 15] illustrates a torsion spring 290 comprising two arms 290A and 290B, intended to be mounted around the axis 210. The arms are configured so that, once installed, the torsion spring exerts a torque tending to pivot the actuating rod in the direction D2, therefore opposite to the direction D3, so that the torsion spring constitutes a return means tending to close the space Esp between the head 224 of the actuating rod 220 and the fixed jaw 240, or to maintain the head 224 in contact with the fixed jaw when this space is closed. Due to its location between the branches 224A and 224B of the head end 224, the spring is protected from direct external contacts, promoting the reliability of the mechanism. Thus, the key manipulation is facilitated by a simple and compact mechanism, easy to implement.
[0062] In this document, the figures are not necessarily to scale. Some features and components may be shown exaggerated relative to other components or in a somewhat schematic form, and some details of conventional elements may not be shown in the interest of clarity and conciseness.
[0063] Of course, the invention is not limited to the embodiment described and variant embodiments can be made without departing from the scope of the invention as defined by the claims.
Claims
Claims
1. Adjustable wrench (200) comprising an actuating rod (220) on which is mounted a head (230) comprising a fixed jaw (240) and a movable jaw (250), the movable jaw (250) is secured to a rack (255) comprising teeth (257) separated by tooth bases (257b), the adjustable wrench further comprises a wheel (260) provided with a thread (261) meshing between the teeth (257) of the rack (255), the tooth bases (257b) each having a concave profile capable of receiving the thread (261) of the wheel (260), in which surfaces of the rack (257f, 257s, 257b) and surfaces of the wheel (26If, 261s, 261b) intended to come into contact with each other having complementary geometries, and in which surfaces of the rack (257f, 257s, 257b) and the wheel (26If, 261s, 261b) intended to come into contact having helical geometries.
2. The adjustable wrench according to claim 1, the concave profile of the tooth bases (257b) being defined by an arc of a circle.
3. The adjustable wrench according to claim 2, the arc of a circle having a radius of curvature greater than or equal to half the outer diameter (0ext) of the thread (261) of the wheel (260).
4. The adjustable wrench according to any one of claims 1 to 3, the teeth (257) each having a summit (257s) of concave profile.
5. The adjustable wrench according to claim 4, the concave profile of the apexes of the teeth being defined by an arc of a circle.
6. The adjustable wrench according to claim 5, the arc of a circle having a radius of curvature greater than or equal to half the internal diameter (0int) of the thread (261) of the wheel (260).
7. The adjustable wrench according to any one of claims 1 to 6, the teeth of the rack extending in a direction (257d) inclined at an angle (a) between 2° and 20° relative to a plane (zx) perpendicular to an axial direction (256d) of a rod (256) of the rack.
8. The adjustable wrench according to claim 1, a mechanical clearance (J) of between 0.02 mm and 0.2 mm being provided between the surfaces of the rack and the wheel intended to come into contact.
9. The adjustable wrench according to any one of claims 1 to 8, the fixed jaw being integral with the actuating rod in a rotatable manner around an axis of rotation (210), the actuating rod (220) comprising an element (224, A2, B2) provided to block a longitudinal movement of the wheel (260) when a torque is exerted on the actuating rod in a tightening direction (D2).
10. The adjustable wrench according to claim 9, comprising a plate (263) mounted coaxially with the wheel (260), interposed between the wheel (260) and the element (224, A2, B2) provided for locking the wheel (260) when the wrench is rotated in a tightening direction (D2), the plate (263) comprising at least one notch (263A, 263B) configured to allow passage of said element (224, A2, B2) provided for locking the wheel (260) when the wrench is rotated in a direction (D3) opposite to the tightening direction (D2) while a fixed object (270) is engaged by the fixed jaw (240) and the movable jaw (250).
11. The adjustable wrench of claim 10, the plate (263) further comprising a concavity (263C) configured to receive a rod (256) of the rack (255).
12. The adjustable wrench according to any one of claims 8 to 11, comprising a torsion spring (290) mounted around the axis (210) of rotation and exerting a force on the actuating rod (220) and the fixed jaw (240) tending to close a space (Esp) between one end (224) of the actuating rod (220) and the fixed jaw (240).
13. The adjustable wrench according to any one of claims 1 to 12, comprising a second return means (264) exerting on the wheel (260) a force tending to bring the movable jaw (250) closer to the fixed jaw (240).