Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
  • B25B—TOOLS OR BENCH DEVICES NOT OTHERWISE PROVIDED FOR, FOR FASTENING, CONNECTING, DISENGAGING OR HOLDING
  • B25B23/00—Details of, or accessories for, spanners, wrenches, screwdrivers
  • B25B23/14—Arrangement of torque limiters or torque indicators in wrenches or screwdrivers
  • B25B23/142—Arrangement of torque limiters or torque indicators in wrenches or screwdrivers specially adapted for hand operated wrenches or screwdrivers
  • B25B23/1422—Arrangement of torque limiters or torque indicators in wrenches or screwdrivers specially adapted for hand operated wrenches or screwdrivers torque indicators or adjustable torque limiters
  • B25B23/1427—Arrangement of torque limiters or torque indicators in wrenches or screwdrivers specially adapted for hand operated wrenches or screwdrivers torque indicators or adjustable torque limiters by mechanical means
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
  • B25B—TOOLS OR BENCH DEVICES NOT OTHERWISE PROVIDED FOR, FOR FASTENING, CONNECTING, DISENGAGING OR HOLDING
  • B25B13/00—Spanners; Wrenches
  • B25B13/02—Spanners; Wrenches with rigid jaws
  • B25B13/08—Spanners; Wrenches with rigid jaws of open jaw type

Definitions

• Rotational drive tool for a screwing member Rotational drive tool for a screwing member.
• the invention relates to a rotary drive tool for a screwing member, in particular a hand tool, of the type comprising a head having at least two gripping surfaces for driving the screwing member by at least partial form complementarity, and means for driving the head in rotation, the head acting generally as a single piece when driving a screwing member in rotation, the head comprising a region for connecting the gripping surfaces and the transmission parts towards the gripping surfaces of a force of rotation applied to the drive means, the connection region being situated between the force transmission parts and the gripping surfaces.
• the invention applies, for example, to open-ended spanners.
• the head of such a key comprises two open rigid jaws which each have a gripping surface for a screwing member such as a nut.
• the two gripping surfaces are facing each other.
• a wrench is used to transmit torque to a nut
• the fork is deformed so that the gripping surfaces move apart.
• the nut therefore, rotates relative to the fork.
• This modifies the support points between the nut and the fork by tending to bring together the force vectors (theoretically parallel) corresponding to the torque. Therefore, for a given torque, the intensity of the corresponding forces increases. This increase in turn leads to an increase in the bending of the fork.
• the phenomenon amplifies itself and, beyond a certain value, there is total rotation of the nut in the fork with often destruction of the latter. We can say that the nut then turns into a real cam which makes the key explode. The phenomenon therefore limits the value of the torques which can be transmitted by such an open-ended open-end wrench.
• This phenomenon is generally present in tools which, unlike for example pliers, do not allow clamping of the gripping surfaces independent of the rotary drive.
• the object of the invention is to solve this problem by providing a tool of the aforementioned type making it possible, for example, to exert increased torques on a screwing member.
• the invention relates to a tool of the aforementioned type, characterized in that the head is adapted so that the action of the drive means in rotation on the force transmission parts tends to deform the geometry of the head to bring the gripping surfaces closer to one another when a drive force in rotation of a screw member is applied via the drive means.
• the tool may include one or more of the following characteristics, taken alone or in any technically possible combination: - the head is adapted so that said action of the drive means in rotation tends to elastically deform the head,
• the means for driving the head in rotation comprise a member for operating the head
• the operating member of the head is movable relative to the latter so as to tend to bring the gripping surfaces closer to one another, by lever or cam effect on the force transmission parts, when 'a drive force in rotation of a screwing member is applied to the operating member,
• the head has a general configuration in H and comprises two branches connected by a central core, a distal region of each branch having one of the gripping surfaces and the proximal regions of the branches forming said force transmission parts, the two branches are movable relative to each other by deformation of the central core to bring the gripping surfaces closer to each other by spacing of proximal regions of the branches, and a distal region of the operating member is arranged between the proximal regions of the branches in order to move them apart, by lever or cam effect, when a drive force in rotation of a screwing member is applied to the actuating member,
• the operating member is connected to the head by a flexible connection
• the flexible connection comprises a deformable part made integrally with the head and the operating member
• the tool comprises removable means for connecting the head and the operating member, - the operating member is orientable relative to the head,
• the operating member is part of a dynamometric tool
• the tool comprises means for adjusting the tendency to deformation of the head under said action of the rotation drive means, the head comprises two open jaws which each have at least one of the gripping surfaces,
• the flexible connection is made of elastomer.
• head having at least two engagement surfaces for driving a screwing member in rotation by at least partial form complementarity is understood here to mean a head enabling such a member to be driven by the fact that their respective shapes, such as for example polygonal shapes, do not allow relative rotation.
• the head also behaves functionally generally as a single piece of stiffness sufficiently large so that, during use, the functional geometry of the head remains generally unchanged, except under the effect of the deformation under load. and the compensation thereof according to the invention as will be described later.
• FIG. 1 is a schematic plan view of an open-ended open-end wrench according to the invention, ready to drive a rotating nut,
• FIGS. 2 and 3 are views similar to FIG. 1, illustrating the key when a screwing force and respectively a force for unscrewing the nut is applied to its handle,
• FIG. 4 is a plan view and enlarged view of the head of the key of FIGS. 1 to 3, schematically illustrating the action thereon of a relative rotation of the handle of the key,
• FIGS. 5 and 6 are enlarged views from above illustrating the head and the distal end of the handle of two variants of the key of FIGS. 1 to 4,
• FIG. 7 is a schematic perspective view of a tool according to another embodiment of the invention
• - Figure 8 is a view similar to Figure 1 illustrating yet another embodiment of the invention.
• FIG. 1 illustrates an open-ended open-end wrench 1 ready to drive a nut 2 in rotation.
• the key 1 essentially comprises a separate head 4 and a handle 5.
• the head 4 which can be made of a material that is less efficient than steel and in particular with a modulus of elasticity of less than 150 GigaPascal, has an H shape and comprises two rectilinear branches 6 longitudinal with respect to a central axis X-X.
• the branches 6 are interconnected by a central and transverse core 7.
• Each branch 6 comprises on either side of the core 7 a distal end region 8 (on the left in FIG. 1), and a proximal end region 9.
• the core 7, made in one piece with the branches 6, is relatively thin and elastically deformable at least in bending.
• the distal end regions or jaws 8 each have a flat surface 10 for engagement with the nut 2.
• the engagement surfaces 10 are oriented towards the inside of the head 4 and face each other.
• the branches 6 are movable in rotation relative to each other in the plane of Figures 1 and 4, on either side of a rest position, as shown in solid lines in Figure 1 and dashed in Figure 4.
• This rest position corresponds to the case where no force is applied to the branches 6.
• the branches are mutually parallel and parallel to the axis X-X.
• the distal 8 and proximal 9 end regions can therefore approach and deviate respectively by bending deformation of the core 7.
• the branches 6 are movable between their rest position and a position in which their distal end regions 8 are brought close together (FIG. 4) while their proximal end regions 9 are separated from one another. As soon as a screw member 2 is inserted between the distal end regions 8 of the branches 6 of the head 4, the mobility of the branches 6 is therefore limited.
• the handle 5 is an elongated bar of axis Y-Y and has a transverse dimension slightly less than the spacing between the two proximal end regions 9 of the branches 6.
• the distal end region 12 of the handle 5 is received with little play between the proximal end regions 9 of the branches 6.
• the longitudinal axis X-X of the head 4 is coincident with the longitudinal axis Y-Y of the handle 5.
• the nut 2 is a hexagon nut received between the distal end regions 8 of the branches 6.
• the gripping surfaces 10 of the head 6 are located opposite two opposite sides of the nut 2.
• the head 4a by its gripping surfaces 10, a shape partially complementary to that of the nut 2.
• the handle 5 is movable in rotation relative to the head 4 in the plane of FIG. 1, on either side of its rest position, between two branches 6 spacing positions illustrated respectively in FIGS. 2 and 3.
• the distal end region 12 of the handle 5 then bears at a point 15 on the free end of the lower branch 6 (in FIG. 2) of the head 4, and in a point 16 adjacent to the core 7 on the other branch 6. Points 15 and 16 are spaced apart from each other longitudinally along the axis XX. The axes X-X and Y-Y are then also inclined relative to each other. In the other spacing position illustrated in FIG. 3, the handle 5 has pivoted relative to the head 4 in the direction 18 of unscrewing the nut 2. The distal end region 12 of the handle 5 is then supported in a first point
• the support points 15 and 16 then have a relative longitudinal position similar to that points 15 and 16 of Figure 2.
• the axes XX and YY are then also inclined relative to each other.
• the operating mode of the key 1 is as follows. When it is desired to screw the nut 2, a force 20 is applied, as illustrated in FIG. 2, to the proximal end region 21 of the sleeve 5 tending to pivot the latter in the direction of rotation 14.
• the handle 5 then reaches the position of FIG. 2 and drives the head 4 in rotation in the direction 14. A screwing torque is therefore applied to the nut
• the proximal end regions 9 then form force transmission parts of the handle 5 towards the grip surfaces 10 and therefore towards the nut 2.
• the handle 5 plays, thanks to the two support points 15 and 16 offset longitudinally, the role of a lever of the first order and tends to spread the proximal end regions 9 of the branches 6 of the head 4.
• the handle 5 when applying a force 24 to unscrew the nut 2 on the proximal end 21 of the handle 5, the handle 5 takes the position illustrated in FIG. 3 and tends on the one hand to drive the nut 2 in the direction of rotation 18 and, on the other hand, by bringing the distal end regions 8 of the branches 6 closer together.
• the leverage produced by the handle 5 tends to oppose the separation by the nut 2 of the gripping surfaces 10.
• the release of the force 24 on the handle 5 allows the return to position rest of the distal end regions 8 of the branches 6.
• the key 1 makes it possible, in the two drive directions, to limit the rotation between the nut 2 and the head 4 and also the risks of the head 4 bursting.
• key 1 allows the transmission of greater torques than a conventional open-ended open-end wrench.
• key 1 allows to access a screwing member as easily as a conventional open-end wrench.
• the key 1 of Figure 5 differs from that of Figures 1 to 4 by the fact that the head 4 and the handle 5 are no longer separated but connected by a longitudinal blade 26 formed integrally with the core 7 of the head 4 and the distal end region 12 of the handle 5.
• This blade 26 can be deformed, for example in bending, so that it forms between the head 4 and the handle 5 a flexible connection allowing the latter to pivot relative to the head 4 to take the positions shown in FIGS. 2 and 3.
• the proximal end regions 9 of the head 4 include four internal beads 27 arranged in pairs on these regions 9.
• the beads 27 of the same region 9 are spaced from one another and face the beads 27 of the 'other region 9. These beads 27 form support reliefs of the handle 5 on the proximal end regions 9 when the handle 5 will take, relative to the head 4, the positions of Figures 2 and 3. It will be noted that in the rest position shown in FIG. 5, the four beads 27 are practically in contact with the handle 5.
• the blade 26 may not have come in one piece with both the head 4 and the handle 5, but fixed by welding to the head 4 and / or to the handle 5.
• the blade 26 is replaced by an elastomer insert, made integral with both the head 4 and the handle 5 by means known per se (mechanical means or injection molding, for example).
• the head 4 includes relief reliefs of the handle 5 against the proximal end regions 9 of the branches 6, namely a pair of beads 28 and a pair of pins 29. These reliefs project from the branches 6 towards the distal end region 12 of the handle 5.
• the beads 28, on the one hand, and the pins 29, on the other hand, are arranged opposite.
• the beads 28 and the pins 29 can be arranged otherwise.
• the beads 28 came integrally each with the proximal end region 9 of a branch 6 and are more distant from the central core 7 than the pins 29.
• the pins 29, of cylindrical shape, are each received in a recess 30 formed in the proximal end region 9 of a branch 6.
• the head 4 carries two pairs of recesses 30 which can receive the pins 29 and which are spaced along the axis X-X. Thus, the spacing along the X-X axis between the pins 29 and the beads
• the beads 28 and the pins 29 define the support points of the handle 5 on the head 4 so that it fulfills its role as a lever. It is then possible to adjust, by modifying the position of the pins 29, the intensity of the tendency for the surfaces 10 to approach, induced by a force in rotation driving a nut 2 applied to the handle 5.
• FIG. 7 illustrates another tool 1 according to the invention which differs from the key of FIGS. 1 to 4 by the fact that the handle has been replaced by an operating member 5 of T shape and which thus comprises a bar 32 of torque transmission extended by a handle 33.
• the distal end region 34 of the operating member 5 is received with little play between the proximal end regions 9 of the branches 6.
• the proximal end regions of the head 4 have four beads 27 for supporting the region 34 of the operating member 5 on the head 4.
• This region 34 has a rectangular section and is provided with a transverse bore 36.
• a transverse pin 37 crosses the two branches 6 and the bore 36. This pin 37 connects the operating member 5 and the head 4 by making it possible to orient the operating member 5 relative to the head 4, by rotation around pin axis 37.
• the bar 32 can be located outside the plane of the head 4, for example inclined or perpendicular to this plane as shown in FIG. 7. This possibility of orientation makes it possible to adapt to various conditions of use, by example for screwing hard-to-reach nuts.
• the user then adapts the effort that he exerts to obtain, in all cases, a torque for driving in rotation on the screwing member. Furthermore, the clearance between the bore 36 and the pin 37 is sufficiently large for, when in the position of FIG. 7, a torque is applied to the rotation of a nut to allow the rotation of the nut.
• bar 32 around its longitudinal axis with respect to the head 4. The region 34 of the bar 32 then bears on the beads 27 and thus tends to spread by cam effect the regions 9 of the branches 6 so as to tend to bring the surfaces of take 10 as before.
• the pin 37 is removable to allow the head 4 and the member 5 to be separated, and therefore to connect heads 4 of different sizes and shapes to the operating member 5.
• the handle is removable to allow the head 4 and the member 5 to be separated, and therefore to connect heads 4 of different sizes and shapes to the operating member 5.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Details Of Spanners, Wrenches, And Screw Drivers And Accessories (AREA)
• Manipulator (AREA)
• Gripping On Spindles (AREA)

Applications Claiming Priority (3)

Publications (2)

Family

ID=9550322

Family Applications (1)

Country Status (7)

Families Citing this family (4)

Family Cites Families (12)

• 1999
  • 1999-09-28 FR FR9912086A patent/FR2798876B3/fr not_active Expired - Lifetime
• 2000
  • 2000-09-01 AT AT00960781T patent/ATE291991T1/de not_active IP Right Cessation
  • 2000-09-01 US US10/088,410 patent/US6557441B1/en not_active Expired - Fee Related
  • 2000-09-01 AU AU72970/00A patent/AU7297000A/en not_active Abandoned
  • 2000-09-01 DE DE60019140T patent/DE60019140T2/de not_active Expired - Lifetime
  • 2000-09-01 EP EP00960781A patent/EP1216120B1/de not_active Expired - Lifetime
  • 2000-09-01 WO PCT/FR2000/002427 patent/WO2001023145A1/fr active IP Right Grant

Non-Patent Citations (1)

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