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Title:
ADJUSTABLE SOCKET DEVICE
Document Type and Number:
WIPO Patent Application WO/2011/086148
Kind Code:
A1
Abstract:
An adjustable socket drive device for wrench, drill and the like comprises a body means (2) having a plurality of parallel cylindrical seats (3) each assigned to house a respective free rotating cylindrical stem means (4) each having a respective eccentric elongated jaw means (5) protruding outside the cylindrical seats (3). Said device (1) further comprising rotating means (6) engaged to the stem means (4) for the rotation of said stem means (4) and of the jaw means (5) adapting the distance between the lasts to accommodate nuts, bolts ad stems of different size. The rotating means (6) comprises a set of slots (10) carried out through the body means (2) and each debouching into a respective cylindrical seats (3) and it comprises a set of concave scores (11) each carried out onto a respective stem means (4), said slots (10) and scores (11) are respectively parallel to the geometric axis of the cylindrical seats (3) and helicoidally shaped or vice versa and each slot (10) and the respective score (11) are slidingly engaged by a corresponding coupling means (12) each moved along the respective slot (10) by an operating means (14) to control the rotation of the jaw means (5) and the mutual distance thereof.

Inventors:
TRAVERSI ALESSANDRO (IT)
Application Number:
PCT/EP2011/050445
Publication Date:
July 21, 2011
Filing Date:
January 14, 2011
Export Citation:
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Assignee:
A L F A COSTRUZIONI MECCANICHE S R L (IT)
TRAVERSI ALESSANDRO (IT)
International Classes:
B23B31/12; B25B13/44; B25F3/00
Foreign References:
DE2131732A11973-01-11
US1564768A1925-12-08
US5918511A1999-07-06
SU1404190A11988-06-23
JP2009202321A2009-09-10
US5819607A1998-10-13
US3618961A1971-11-09
US20040140629A12004-07-22
US4580483A1986-04-08
DE2131732A11973-01-11
Attorney, Agent or Firm:
NEGRINI, Elena (Via dell'Angelo Custode 11/6, Bologna, IT)
Download PDF:
Claims:
CLAIMS

Adjustable socket drive device for wrench, drill and the like comprising a body means (2) having a plurality of parallel cylindrical seats (3) each assigned to house a respective free rotating cylindrical stem means (4) each having a respective eccentric elongated jaw means (5) protruding outside the cylindrical seats (3); said device (1) further comprising rotating means (6) engaged to the stem means (4) for the rotation of said stem means (4) and of the jaw means (5) adapting the distance between the lasts to accommodate nuts, bolts ad stems of different size; said device (1) being characterized in that the rotating means (6) comprises a set of slots (10) carried out through the body means (2) and each debouching into a respective cylindrical seats (3) and it comprises a set of concave scores (11) each carried out onto a respective stem means (4), said slots (10) and scores (11) are respectively parallel to the geometric axis of the cylindrical seats (3) and helicoidally shaped or vice versa and each slot (10) and the respective score (11) are slidingly engaged by a corresponding coupling means (12) each moved along the respective slot (10) by an operating means (14) to control the rotation of the jaw means (5) and the mutual distance thereof.

Device according to claim 1 characterized in that the operating means (14) is ring shaped and it is constrained to rotate around the body (2) almost without axial translation, the inner face of said annular operating means (14) is provided with one helicoidal thread (60) for each coupling means (12) where each helicoidal thread (60) has a concave transversal section complementary in respect to a portion of said coupling means (12) for slidingly housing said portion.

Device according to claim 1 characterized in that the operating means (14) is annular shaped and its internal face is provided with a concave annular groove (13) having concave annular shape with transversal section complementary shaped in respect to a portion of said coupling means (12) for slidingly housing said portion, and said face is equipped with at least one female threading (15) engaged with at least one male thread (16) carried out on the external side of the body means (2) at least close to the slots (10); the rotation of the operating means (14) causes the axial translation thereof and the rotation of the jaw means (5). Device according to claim 2 or 3 characterized in that each coupling means (12) is preferably sphere shaped and the transversal section of each helicoidal thread (60) or annular groove (13) is circular arch shaped, the radius of said circular arch is equal or slightly bigger than the radius of said sphere.

Device according to claim 1 characterized in that the generatrix at least of a matching portion of the side surface of the elongated jaw means (5) are straight and parallel to the main geometric axis of the cylindrical stem means (4) and of the cylindrical seats (3); were in case of hexagonal nuts, bolts ad stems, preferably the cylindrical seats (3) are in number of three and the respective main geometric axis orthogonally cut the vertex of an equilateral triangle.

Device according to claim 2 characterized in that each jaw means (5) is inscribable inside a geometric cylindrical side wall coaxial with the respective stem means (4) and the transversal section of said jaw means (5) is asymmetric and preferably it has three main side forming a sort of triangle, one of said sides consisting of the arch of circumference made by the intersection of the section plane with said geometric cylindrical side wall, and the remaining two sides are bevelled and they have very different length and they are slightly convex curved and they form and intermediate angle of 90° or preferably bigger.

Device according to any of the preceding claims characterized in that the end of the body means (2) opposed to the cylindrical seats (3) is provided with an axial cavity (65) communicating with said cylindrical seats (3) and assigned to house blocking washer (67), assigned to axially block the stem means (4), slidingly engaged in annular groves (68) of said stem means (4).

Device according to any of the claims 1 - 6 characterized in that the body means (2) comprises a set of hollow first radial seats (7) each interfering with one or two cylindrical seats (3) and assigned to be engaged by a respective pin means (8), each stem means (4) is provided with an annular concave seat (9) assigned to be engaged by one or two pin means (8) allowing the free rotation of the each stem means (4) and preventing the axial sliding thereof. Device according to any claims 1 - 6 characterized in that the body means (2) comprises a set of hollow second radial seats (47) each having one end ending into the respective cylindrical seat (3) and assigned to house respective sphere means (48), each stem means (4) is provided with an concave seat (49) annular or arch shaped assigned at least to be engaged by one sphere means (48) allowing the free rotation of the each stem means (4) and preventing the axial sliding thereof.

Device according to claim 5 characterized in that the end of each second radial seats (47) opposed to the respective cylindrical seat (3) flows into a cylindrical hole (50) made into the body means (2) and the respective geometric axis is parallel and equidistant to the geometric axis of the cylindrical seats (3); said cylindrical hole (50) is provided with an axial female thread to be axially engaged by a threaded pin (51) whose head (52) is conical or ogival shaped and it is assigned to slidingly match with all the sphere means (48) to engage said sphere means (48) into the respective concave seat (49) made in the stem means (4).

Device according to any of the preceding claims characterized in that the end of the body means (2) opposite to the jaw means (5) is equipped with a socket or connection (20) for a tool.

Device according to claim 3 characterized in that the portions (17) of the external side of the body means (2) interposed between the male threads (16) are almost flattened or slightly concave.

Device according to claim 12 characterized in that at lest one of the flattened portions (17) is provided with a scale referring to the axial position of the operating means (14) along the body means (2).

Device according to claim 12 characterized in that it comprises a set of sliding blocks (30) each interposed between a flattened portions (17) and the annular operating means (14) and complementary shaped in respect to the groove (13) and to the flattened portions (17), each sliding blocks (30) is provided with a radial hole (31) housing a spring (32) and a ball (33) elastically matching with the surface of the groove (13) that is provided with stop holes (34) assigned to detachably stop the ball (33) and the rotation of the annular operating means (14) in predetermined mutual distance among the jaw means (5).

Device according to claim 2 characterized in that it comprises a tubular member (75) fixed to the body means (2) and freely slidingly matching with one end of the operating means (14) avoiding the axial translation thereof cooperating with a shoulder (76) of the body means (2), where said shoulder (76) freely slidingly matches with the other end of the operating means (14).

Device according to claim 15 characterized in that it comprises an annular sealing means (79) interposed with friction between the the body means (2) and the tubular member (75).

Device according to claim 15 characterized in that the end of the tubular member (75), matching with the operating means (14) in a rotating manner, comprises a set of longitudinal concave seats (80) each housing a respective small sphere (81) and a corresponding resilient means (82) acting on the respective small sphere (81) for pushing it against scores (83) carried out into the edge of the operating means (14) for detachably blocking it in predetermined positions.

Device according to claim 15 characterized in that it comprises an inch scale (90) and/or a metric scale (91), one made on the operating means (14) and the other made onto the tubular member (75).

Device according to claim 7 characterized in that it comprises a closing means (69) blocked into the axial cavity (65), for the blocking washer (67) engaged to the stem means (4), and it comprises an elastic means (70) compressed between said closing means (69) and blocking washer (67) for elastically pushing the latter (67) toward the exit from the respective cylindrical seats (3).

Device according to any of the preceding claims characterized in that the portion of each cylindrical seats (3) opened toward the outside has a cylindrical or frustoconical shaped enlargement (55) assigned to house a respective beveled portion (56) interposed between each jaw means (5) and the respective cylindrical stem means (4) and having shape respectively cylindrical or frustoconical complementary to the enlargement (55).

Device according to any of the preceding claims characterized in that the pitch of the helicoidal concave scores (11) is variable.

Device according to claims 2, 18 and 21 characterized in that the pitch of the helicoidal threads (60) of the operating means (14) is constant and the pitch of the helicoidal concave scores (11) increases in the direction from the end of the stem means (4) carrying jaw means (5) to the opposite end so the distances among the numeric indexes of the inch scale (90) and/or of the metric scale (91) are constant.

Description:
ADJUSTABLE SOCKET DEVICE

TECHNICAL FIELD The present invention is framed into the technical field of the mechanical tools and it refers to an adjustable socket drive device for bolt or nut driver tool, for drills, for device and machine tools and especially assigned to engage various sizes of hexagonal nuts or bolts and to tighten or to loose them ad assigned, similarly to a mandrel, to engage the cylindrical or hexagonal stems of drilling bits, of twist bits or of other rotating tools.

BACKGROUND ART

The known hand or powered bolt driver tools have a rotating link assigned to be connected to various known hexagonal socket drives each provided with a hexagonal seat having a respective size corresponding to the size of the hexagonal socket heads of the bolts or nuts to be screwed or unscrewed.

A drawback of said known not adjustable hexagonal socket drives consists in that they must be replaced to fit different sizes of hexagonal socket head of bolts or nuts to be engaged.

A further drawback of said hexagonal socket drives consists in that they can match hexagonal socket heads only.

Document n. DE 21 31 732 discloses an adjustable socket drive device comprising a body means provided with a plurality of cylindrical seats, each assigned to house in a freely swivelling manner a respective stem means having a respective eccentric and elongated jaw means protruding outward in respect of the corresponding housing.

Said known device comprises rotating means engaged to the stem means for rotating them and the jaw means for adjusting the mutual distance thereof to the various sizes of the nuts, bolts or stems.

DISCLOSURE OF THE INVENTION An object of the present invention is to propose a socket drive device adjustable between two extreme minimum and maximum sizes, for engaging heads and cylindrical or hexagonal stems whose sizes range between said minimum and maximum.

Further object is to propose a simple, effective and reliable device.

Another object is to propose an adjustable socket drive device also operating as a mandrel for drills and rotating tools that can be engaged to various sizes of twist bit stems, disk saws stems, milling cutter stems and other rotating tools.

Further object is to propose an adjustable socket drive device that can be tighten on hexagonal or cylindrical heads and stems by hand, without the need of spanner, tools or the like. BRIEF DESCRIPTION OF THE DRAWINGS

The features of the invention are highlighted in the following whit particular reference to the enclosed drawings in which:

figure 1 shows a front view of an embodiment of the adjustable socket drive device object of the present invention;

figure 2 shows a view sectioned according to the plane II - II of figure 1;

figure 3 shows an axial view of the device of figure 1;

figures 4 and 5 show section views respectively according to planes IV - IV and V - V of figure 1;

- figure 6 shows an axonometric view of the device of figure 1;

figure 7 shows an exploded and axonometric view of the device of figure 1 ;

figures 8 - 10 show axial views of the device of figure 1 in different adjustment conditions for rotating nuts of different sizes;

figure 11 shows a front view of a different embodiment of the device of figure 1;

- figure 12 shows a section view according to the plane XII - XII of the embodiment of figure

11;

figure 13 shows an axial view of the device of figure 11;

figures 14 and 15 show section views respectively according to plans XIV - XIV and XV - XV of figure 11 ;

figure 16 shows an axonometric view of the device of figure 11;

figure 17 shows an axonometric and exploded view of the device of figure 11;

figure 18 shows a section view according to a longitudinal axial plane of a further embodiment of the device of figure 1 ;

figures 19 and 20 show views sectioned by planes respectively XIX - XIX and XX - XX of figure 18;

figure 21 shows an exploded and axonometric view of the device of figure 18;

figures 22 - 24 show respectively side, axial and axonometric views of the preferred embodiment of the device object of the present invention;

figure 25 shows a view sectioned according to plane XXV - XXV of figure 22;

figures 26 and 27 show views of the device of figure 22 sectioned according to planes XXVI

- XXVI and XXVII - XXVII of figure 25;

figures 28 and 29 show respective enlarged portions of figure 25;

- figure 30 shows an axonometric and exploded view of figure 22;

figures 31 - 33 show axial views of the device of figure 22 in conditions of engagement with nuts of various sizes.

EMBODIMENTS OF THE INVENTION

Referring to figures 1 - 10, 1 indicates a simplified embodiment of the adjustable socket drive device, object of the present invention, associable to mounts, adjustable spanner, drills, manual or powered tool drives and the like and assigned to engage or to grab nuts and bolts or stems of bits and of rotating tools and in general for hexagonal heads or cylindrical stems.

The device 1 comprises a body means 2, for instance made of ferrous metal, cylinder or regular prism shaped and having a main longitudinal geometric axis.

In the body means 2 are carried out, for instance by means of drilling, three cylindrical seats 3 whose main geometric axes are parallel to the main geometric axes of the body means 2 and they cut perpendicularly the vertexes of an equilateral triangle.

Each cylindrical seat 3 is assigned to house, in a freely swivelling manner, a respective cylindrical stem means 4.

Each of the three cylindrical stem means 4 has a respective eccentric elongated jaw means 5 protruding outward the cylindrical seats 3 and outward the body means 2.

The portion of the body means 2 where outflow the cylindrical seats 3 has a side wall 18, approximatively cup shaped, partially containing the jaw means 5 without separation of said jaw means 5. The end of the body means 2 opposed to the jaw means 5 and to the side wall 18 is provided with a socket connection or link 20 for a manual operated tool or for a drill or the like.

Said device 1 further comprises rotating means 6 engaged to each stem means 4 for the rotation of said stem means 4 and of the jaw means 5 adjusting the distance between said jaw means 5 for housing nuts, bolts and hexagonal or cylindrical stems of various sizes.

In alternative the invention provides that the number of stem means 4 and of jaw means 5 can differ from three or that one or two of the jaw means 5 can be fixed. In this latter case the alignment and the centreing of the device with the hexagonal or cylindrical elements are not reached.

The geometric generatrix of the portions of the side surfaces of the elongated jaw means 5 assigned to match with nuts, bolts, stems, etc., are straight and parallel to the main geometric axes of the cylindrical stem means 4 and of the cylindrical seats 3.

Each jaw means 5 is inscribed in a cylindrical geometric wall coaxial to the respective stem means 4 and preferably having diameter bigger then the diameter of the stem means 4.

The transverse section of said jaw means 5 is unsymmetrical and preferably it has three main sides forming a kind of triangle whose vertexes are rounded.

The biggest of said sides consists in the circumference arch made by the intersection of the transversal section plane with said cylindrical geometric wall. The two remaining sides, whose common vertex is bevelled by means of a rounding off having a predetermined radius, have very different lengths, for instance the smaller one ranges between one quarter and one half of the bigger one.

Said two remaining sides of the transversal section are convex and slightly curved shaped and they form an interposed angle of about 90° o preferably bigger.

Said structure of the jaw means allows the matching with the sides of the hexagonal heads and nuts far from the axial geometrical planes of the said heads, so helping the forces and torque transmission. Furthermore said jaw means can also grab cylindrical stems.

The body means 2 comprises three cylindrical shaped first concave radial seats 7, each located between two cylindrical seats 3 and interfering with said seats 3.

Said first concave radial seats 7 are assigned to be engaged by respective pin means 8 that thus enter partially and tangentially into the cylindrical seats 3.

Each stem means 4 is provided with an annular concave seat 9 assigned to be engaged by two pin means 8 that allow the free rotation of the stem means 4 avoiding the axial sliding thereof 4.

The rotating means 6 comprise three slots 10 elongated and parallel to the main geometric axes of the body means 2. Each slot 10 crosses the body means where said body release the wall of the respective cylindrical seat 3, releasing a communication between a side portion of the latter 3 with the outside.

The rotating means 6 comprise three scores 11 concave and helicoidal shaped, each 11 made in a respective stem means 4.

In alternative, said slots 10 can be helicoidal shaped and the scores 11 can be parallel in respect to the geometric axes of the cylindrical seats 3, in other word of the respective stem means. The rotating means 6 further comprise three coupling means 12, for instance pin shaped or preferably sphere shaped, each of them is engaged into a corresponding slot 10 and into the respective score 11.

The external end of each coupling means 12 is at least partially housed in a groove 13 of an operating means 14 of the rotating means 6.

Said operating means 14 translates along the body means 2 for controlling the rotation of the jaw means 5 and their mutual distance.

Said operating means 14 is annular shaped and its inner face is provided with the groove 13 having annular concave shape; furthermore, said inner face of the operating means 14 is provided with at least one female threading 15 engaged to at least a male thread 16 made onto the external face of the body means 2 at least close to the slots 10.

The rotation of the operating means 14 causes its axial translation and, by means of the spheres of the coupling means 12, the rotation of the jaw means 5. Obviously the helicoidal scores 11 are phased in respect to the respective jaw means 5 for the synchronous and consistent rotation of the latter 5

The portions 17 of the external face of the body means 2 interposed between the male threads 16 are almost flat.

At least one of said flat portions 17 is provided with a scale referring to the axial position of the operating means 14 along the body means 2 to gauge in millimetres and/or in inches the jaw means 5 adjustment for the size of an hexagonal nut engaged or to be engaged. The operation of the device provides that it can be adjusted manually acting on the operating means 14 for adjusting the jaw means 5 for various sizes of heads, nuts and hexagonal or cylindrical stems. In the further embodiment of figure 11 - 17, the portions 17 of the external face of the body means 2 are slightly concave.

Said embodiment comprises a set of sliding blocks 30, for instance three or less, each interposed between a portion 17 and the annular operating means 14.

Each sliding block 30 is complementary shaped in respect to the groove 13 and to the portion 17 to avoid disengagement from the operating means 14 and to follow it 14 along the longitudinal translation thereof 14.

Each sliding block 30 is provided with a radial hole 31 opened only towards the outside and housing a spring 32 and a sphere 33.

Said sphere 33 elastically matches with the surface of the groove 13 that is provided with stop holes 34 assigned to detachably block the spheres 33 and the rotation of the annular operating means 14 in correspondence of predetermined distance among the jaw means 5 corresponding to precise sizes of the hexagonal heads.

The further embodiment of the device of figures 18 - 21, does not comprise the pin means 8 of figures 1, 11, but it is provided with other means assigned to avoid the taking off of the stem means 4 and of the jaw means 5 allowing the axial rotation thereof 4,5.

This further embodiment provides that the body means 2 includes a set of concave cylindrical shaped second radial seats 47 radial oriented in respect to the longitudinal geometric axes of the body means 2.

One end of each second seat 47 flows into a respective cylindrical seat 3 and the other end flows into a cylindrical hole 50 made inside the body means 2.

For instance, the second radial seats 47 can be carried out into the body means 2 through the slots 10.

The geometric axes of the cylindrical hole 50 is parallel and equidistant in respect to the geometric axes of the cylindrical seats 3; in particular the cylindrical hole 50 and the body means 2 are coaxial.

The second radial seats 47 are assigned to house respective sphere means 48, for instance spheres for ball bearing or, in alternative, pieces in form of small cylinders with hemisphere shaped ends.

Each stem means 4 is provided with an annular concave seat 49 whose transversal section is round arch or annular sector shaped.

Each concave seat 49 is assigned to be engaged by a respective sphere means 48 allowing the free rotation of each stem means 4 and stopping the axial sliding thereof 4.

The inner face of the cylindrical hole 50 is threaded forming an axial female threading engaged by a threaded pin 51 having a head 52 conical or ogival shaped and assigned to slidingly match with the sphere means 48 for constraining them 48 into the respective concave seats 49 carried out in the stem means 4.

The cylindrical hole 50 is made in the bottom of the concave socket connection or link 20.

The present embodiment of the device allows to adjust the axial play of the stem means 4 and jaw means 5 and it allows a fast assembly and disassembly of the latter 4, 5.

In the above described embodiments, the portion opened toward the outside of each cylindrical seat 3 has an enlargement 55 cylindrical or frustoconical shaped; said enlargement 55 is assigned to house a respective bevelled portion 56 interposed between each jaw means 5 and the respective cylindrical stem means 4.

Each bevelled portion 56 is cylindrical or frustoconical shaped and is complementary shaped in respect to the corresponding enlargement 55.

The figures 22 - 33 show the preferred embodiment of the adjustable socket drive device for nuts, bolts, and hexagonal or cylindrical stems or bits in general. Said preferred embodiment differs from the preceding embodiments mainly because of the following features. The annular operating means 14 is axially almost blocked and it 14 can rotate around the geometric axis of the body means 2 only.

The inner face of the annular operating means 14 is provided with one helicoidal thread 60 for each coupling means 12 spheres.

The transversal section of each helicoidal thread 60 is concave and complementary to a portion of said coupling means 12 for slidingly housing said portions thereof 12; in particular said transversal section is arch or portion of circumference shaped. The radius of said arch or portion of circumference is equal to or slightly bigger than the radius of each spheres of said coupling means 12.

The end of the body means 2 opposed to the cylindrical seats 3 is provided with an axial cavity 65, cylindrical shaped, communicating with said cylindrical seats 3 and assigned to house a blocking washer 67 interfering with said cylindrical seats 3 and slidingly engaged into annular scores 68 carried out into the stem means 4.

Said annular scores 68 interfere with the corresponding helicoidal scores 11 for allowing an easy coupling between said blocking washer 67 and said annular scores 68.

The blocking washer 67 thus stops the unwanted taking off of the stem means abutting against the bottom or a proper shoulder made into said axial cavity 65.

The axial cavity 65 for the blocking washer 67 further comprises a housing seat for a closure means 69, for instance consisting of a kind of flange dab joinable into the respective seat made in the axial cavity 65.

The latter axial cavity 65 further houses an elastic means 70 compressed between said closure means 69 and the blocking washer 67 for impressing to the latter 67 a resilient force directed toward the outside of the respective cylindrical seats 3.

Said configuration allows a reduction of the rotation frictions of the stem means 4 during the operations of adjustment of the distance among the jaw means 5 and in absence of axial load.

The preferred embodiment of the device 1 further comprises a tubular member 75, for instance a cylindrical shaped wall, or frustoconical or shaped in form of a cylinder surmounted by the truncated cone.

The tubular member 75 is fixed to the body means 2 and it 75 matches in a freely swivelling manner an end of the operating means 14 blocking the unwanted axial translation cooperating with a shoulder 76 of the body means 2. Said shoulder 76 slidingly matches the other end of the operating means 14.

The tubular member 75 is axially blocked to the body means 2 by means of a resilient ring 77, for instance a Seeger ring, engaged in a cave annular seat carried out into the end of the body means opposed to the jaw means 5.

Furthermore an annular sealing means 79, for instance an O-Ring, interposed with friction between the body means 2 and the tubular member 75, acts against the rotation of the tubular member 75 in respect to the body means 2. The end of the tubular member 75 swivelling matching the operating means 14 comprises a set of concave longitudinal seats 80 each housing a respective small sphere 81 and a corresponding elastic means 82 acting against the small sphere 81 for pushing it 81 against scores 83 carried out in the edge of the operating means 14 for elastically blocking it 14 in preset positions. The preferred embodiment of the device further comprises inch 90 and metric 91 round scales, one carried out onto the operating means 14 and the other onto the tubular member 75 of the body means 2. In said preferred embodiment of the device 1, the pitch of the helicoidal concave scores 11 is variable and the pitch and lead of the helicoidal threads 60 of the operating means 14 is constant.

In particular, the pitch of the helicoidal concave scores 11 increases in the direction from the end of the stem means 4 carrying the respective jaw means 5 to the opposite end in a manner that the distances among the numeric indexes of the metric scale 91 are constant.

The helicoidal threads 60 and the helicoidal concave scores 11 can be left-handed or, in alternative, right-ended or they can have different oriented hands.

Due to said variable pitch of the helicoidal concave scores 11 and to the jaw means 5 shape, the rotation of the annular operating means 14 for adjusting the jaw means 5 from a metric nut size to an adjacent size is fixed and independent by sizes. Furthermore, the jaw means 5 are tapered and only the portion assigned to match nuts and bolts of the side surface of the jaw means 5 has straight generatrix parallel to the main axis of the device.

An advantage of the present invention is to provide a socket drive device adjustable between two extreme minimum and maximum sizes, for engaging heads and cylindrical or hexagonal stems whose sizes ranges between said minimum and maximum.

Another advantage is to provide an adjustable socket drive device also operating as a mandrel for drills and rotating tools that can be engaged to various sizes twist bit stems, disk saws stems, milling cutter stems and the like.

Further advantage is to provide an adjustable socket drive device that can be tighten on hexagonal or cylindrical heads and stems by hand, without the need of spanner, tools or the like. Further advantage consists in keeping the centreing of the socket heads and stems into the device and the device irrespective of the size of said heads and stems.

Further advantage is to provide a simple, effective and reliable device.