SOCKET FOR A WRENCH AND METHOD OF LOOSENING A FASTENER

Field of Invention

This invention relates to a socket to be used with a handle as a wrench (in Great Britain wrenches are referred to as spanners) which can be used for the purpose of tightening or slackening various types of nuts, bolts or screws (hereinafter referred to as fasteners).

Background to the Invention

The head portion of a ring wrench or socket usually has an inner shape and size complementary to that of a typically hexagonal fastener head. The head of such a wrench has an inner surface, which surrounds the fastener head with only a small amount of play between the inner surface of the wrench or socket and the fastener head. As torque is applied to the wrench or socket the torque is transmitted to the fastener head to turn the fastener in the appropriate direction.

Ring-type sockets and wrenches are preferable to open jaw type wrenches and sockets as the torque applied to the wrench is transmitted to the fastener via a much larger contact area and the ring head of the socket or wrench Ring-type sockets and wrenches can also transmit far greater torque without harmful distortion of the fastener head and with less chance of the wrench or socket slipping off the fastener. However, if incorrectly sized, poor quality or open wrench has been used on a stubborn or tight fastener and the fastener head has become inoperable by reason of damage or corrosion, the fastener would normally require to be removed by other means than a socket or wrench. A further problem is that sometimes when using a wrench further purchase power may be required to tighten or slacken a fastener. Ring wrenches or sockets however can seldom be used to operate damaged or rounded fasteners, in particular those in recessed areas where the space surrounding the fastener head is restricted. Torque tightening wrenches which can operate partially rounded fasteners are known, but these normally require unrestricted access to the fastener head. These wrenches / sockets are incapable of operating severely damaged or worn fastener heads.

Summary of the Invention

The invention provides a socket for a wrench, said socket comprising a fixed portion provided with a first fastener receiving aperture and a rotatable portion provided with a second fastener receiving aperture, said fixed and rotatable portions being disposed such that said first and second fastener receiving apertures are in overlying relationship to define a fastener receiving

space and said rotatable portion being rotatable with respect to said fixed portion to adjust said fastener receiving space.

The invention also includes a method of loosening a fastener, said method comprising locating a socket having a fixed portion defining a plurality of fastener engaging faces and a rotatable portion having a plurality of fastener engaging faces over said fastener, applying a rotational force to said socket such that there is relative rotation between said fixed and rotatable portions to cause an adjustment of a fastener receiving space defined by said fastener engaging faces.

Brief Description of the Drawings

Embodiments of the present invention will now be described by way of example, with reference to the accompanying drawings in which: -

Fig 1 illustrates in perspective a first embodiment of a socket for a wrench and a spigot drive ratchet for driving the socket;

Fig 2 illustrates in perspective the various component parts of the socket of Fig 1 ;

Fig 3 illustrates in perspective a second embodiment of a socket in the form of a wrench head; Fig 4 illustrates in perspective the various component parts of the socket of Fig 3;

Fig 5 a illustrates in plan view a fixed ring portion of the socket of Fig 1 ;

Fig 5b shows a plan view of a rotatable ring portion of the socket of Fig 1;

Fig 5c illustrates in plan view parts of the socket of the socket of Fig 1 at rest;

Fig 5d illustrates in plan view the parts from Fig 5c with the rotatable ring portion fully rotated in relation to the socket body;

Fig 6a illustrates in plan view parts of the socket of Fig 1 engaged on a worn fastener drive surface with the rotatable ring portion partially rotated in the drive direction;

Fig 6b illustrates in plan view the rotatable ring portion of Fig 6a fully rotated in the drive direction; Fig 6c illustrates in plan view parts of a third embodiment of a socket for a wrench;

Fig 6d illustrates in plan view the third embodiment with the rotatable ring portion is fully rotated;

Fig 7a illustrates in perspective view a fourth embodiment of a socket for a wrench;

Fig 7b illustrates in perspective view the component parts of the fourth embodiment; Fig 8a illustrates in perspective view a fifth embodiment of a socket for a wrench;

Fig 8b illustrates in perspective view the component parts of the fifth embodiment;

Fig 9a illustrates in plan view parts of the fifth embodiment in the unoperated or at-rest position;

Fig 9b illustrates in plan view the parts of the fifth embodiment shown in Fig 9 fully operated in the clockwise direction (30° in this example); and

Fig 9c illustrates in plan view the parts of the fifth embodiment shown in Fig 9a fully operated in the anti-clockwise direction (30° in this example).

Reference to the Drawings hi the drawings like features will be given like numbers as follows: 1. Socket for a wrench. 5a. Post fixed end.

2. Rotatable ring portion. 5b. Post retention end. 2a. Rotational slots. 7. Fixed wrench portion.

2b. Fastener drive surface. 7a. Fixed wrench post retention holes.

2c. Fastener drive concave surface. 40 7b. Fastener drive surface. 2d. Fastener drive convex surface. 7c. Rotational ring portion slot.

2e. Corrugated surface. 8. Handle portion.

2f. Rotatable ring incorporated post. 8a. Handle grip.

2g. Rotatable ring recess. 9. Fastener.

3. Socket body portion. 45 9a. Fastener drive surface. 3a. Post fixing holes. 9b. Fastener drive undulations.

3b. Fastener drive surface. 9c. Worn / damaged fastener drive

3c. Housing inner recess. surface .

3d. Drive spigot recess. 9d. Circular fastener drive surface.

3e. Socket body housing. 50 10. Resilient portion. 3f. Socket body incorporated post. D Drive direction

3g. Socket body rotatable ring recess. O Offset direction

3h. Positioning mark. A/F Across the flats

3i. Positioning pin slot. AJC Across the corners.

3j. Free end of housing inner recess 55 A 6 point. 4. Fixed ring portion. B 12 point.

4a. Fixed ring post holes. 11. Spigot drive ratchet.

4b. Fixed ring fastener drive surface. 11a. Drive spigot.

4c. Fastener drive surface recess. 12. Positioning pin.

4d. Post recess. 5. Post.

Detailed Description of the Illustrated Embodiments

Fig 1 illustrates in perspective a first embodiment of a socket (1) for a wrench comprising a socket body (3), rotatable ring portion (2) and a fixed ring portion (4). The socket body (3) has a drive spigot recess (3d) complementary to a known drive spigot (1 Ia) ratchet (11).

Fig 2 illustrates the socket (1) dismantled, showing it's various component parts, including the socket body portion (3) with it's post fixing holes (3a) in which respective ends (5a) of the posts (5) are retained. The rotatable ring portion (2) is restricted in rotational movement by the engagement of the posts (5) with the ends of the rotational slots (2a). The fixed ring portion (4) is suitably retained by the posts (5) within the fixed ring post holes (4a) and the post retention ends (5b) at their extremities. A fastener (9) with it's fastener drive surface (9a) is also illustrated.

Fig 3 shows a second embodiment of a socket (1) for a wrench in the form of a wrench head. The rotatable ring portion (2) is retained within a slot (7c) by the posts (5) and the fastener drive surface (2b) preferably has a polygonal surface similar to the profile of the fastener drive surface (7b) of the fixed wrench portion (7). A handle portion (8) with an optional grip (8a) has a socket (1) .

Fig 4 shows the various component parts of the wrench head form of the socket (1) illustrating the fixed wrench portion (7), the posts (5) with the post retention ends (5b) at either end which are fixed within the fixed ring post holes (7a) and through the rotational slots (2a) and the slots (7c) for the respective rotatable ring portions (2).

Fig 5a shows an example of the fixed ring portion (4) of Figs 1 and 2 illustrating the across the flats (A/F) measurement within the fixed ring fastener drive surface (4b) recess (4c). The fastener drive surface (3b) of the socket body (3) corresponds to the fastener drive surface (4b).

Fig 5b illustrates an example of the rotatable ring portion (2) having a fastener drive surface (2b) comprising a fastener drive concave surface (2c), a fastener drive convex surface (2d) and a further corrugated surface (2e).

Figs 5c and 5d shows the socket (1) of Figs 1 and 2 with the said fixed ring portion (4) removed and the drive surfaces (2b) and (3b) shown flat for ease of representation, hi Fig 5 c,

the posts (5) are in their unoperated position in relation to the said rotational slots (2a). The flank drive or six point (A) fastener drive surfaces (2b and 3b) and the across the corners (A/C) measurement are also indicated. It will be appreciated that the six point (A) fastener drive surface (4b) and the A/C measurement for the fixed ring portion (4) corresponds to that of the socket body (3).

Fig 5d shows the posts (5) in their fully operated position in relation to the rotational slots (2a). The six point (A) has now become a twelve point (B) composite of the fastener drive surfaces (2b, 3b) (and 4b) and usefully the said across the corners (A/C) measurement has also been substantially reduced.

Figs 6a and 6b illustrate the socket (1) of Figs 1 and 2 with the fixed ring portion (4) removed and a worn / damaged fastener drive surface (9c) engaged by the rotatable ring portion (2) fastener drive surface (2b) and socket body portion (3) fastener drive surface (3b). When operated in the drive direction (D) the rotatable ring portion (2) rotates within the confines of the rotational slots (2a) restricted by the posts (5). In Fig 6a the socket (1) is shown partially operated in the drive direction (D), yet imparting a substantial grip on the undersized, worn or damaged fastener drive surface (9c) via the remaining fastener drive undulations (9b). The corrugated surface (2e) provides further mechanical grip upon the worn or damaged fastener drive surface (9c). Fig 6b shows the rotatable ring portion (2) fully operated imparting further grip on the fastener drive surface (9b, 9c).

When the socket (1) is operated in the drive direction (D) as in Fig. 6a and the rotatable ring portion (2) has sufficient grip on the fastener drive surface (9c) or is manually held and the socket body (3) further rotated in the drive direction (D), it's said fastener drive surfaces will come into contact with any undulations (9b) left on the damaged or worn fastener drive surface (9c) in an ever tightening manner until locked upon the damaged or worn fastener drive surface (9c). Any further torque applied to the socket (1) in the drive direction (D) is transmitted to the fastener (9) in order to operate the same. As shown in Fig. 6b, if the rotatable ring portion (2) is fully operated within the confines of the rotational slots (2a) , the essentially "flank drive" or "six point" (A) that is illustrated in Fig. 5c is transformed into a the twelve point (B) of a smaller size shown in Fig. 5d. For example, an unoperated 17mm A/F is approximately 19.8mm widest A/C is transformed to an operated 17mm widest A/C equivalent to 14.65mm A/F.

It will be understood that the description of the operation of the parts (2), (3) and (4) given with reference to Figs 5a to 6b applies equally to the parts (2) and (7) of the second embodiment shown in Figs 3 and 4.

Figs 6c and 6d illustrate in plan view a third embodiment of the socket (1) where, for illustration purposes only, the fixed ring portion (4) is removed. In this embodiment the rotatable ring portion (2) in relation to the socket body (3) is eccentric in that, as shown in Fig 6c, initially the profiles of the at-rest socket body fastener drive surface (3b) and the rotatable ring portion (2) fastener drive surface (2b) are aligned but as shown in Fig 6d when the rotatable ring portion (2) is rotated relative to the said socket body (3) the posts (5) act upon the suitably offset said rotational slots (2a) to cause the fastener drive surface (2b) to travel in the offset (O) direction, further reducing the said across corners (A/C) distance in that direction and thereby increasing the drive grip upon the fastener (9) to be operated enabling even a circular fastener drive surface (9d) to be operated.

Figs 6c and 6d further show in plan view the said rotatable ring portion (2) provided with bias members (10) in the form of springs fitted in the rotation slots (2a). The bias members 10 act against respective posts (5) to urge the rotatable ring portion (T) into the open position at which the fastener drive surfaces (2b, 3b) form a similar profile . Fig 6d shows the rotatable ring portion (2) rotated in the drive direction (D) against the bias members (10), which are compressed to store a restoring force for restoring, or returning, the rotatable ring portion (2) to the open position.

Figs 7a and 7b show a fourth embodiment of a socket (1) for a wrench which operates in the same general manner to that shown in Figs 6a and Fig 6b. As illustrated in Fig 7a, when in the unoperated or at-rest position, the fastener drive surface (2b) is generally aligned with a fixed fastener drive surface (4b). In this embodiment, for ease of manufacture, the fastener drive surface (3b) of the socket body housing (3) of the Figs 1 and 2 embodiment has been replaced by a fastener drive surface (4b) defined by an inner fixed ring portion (4). An outer fixed ring portion (4) is fixed by known means to the socket body housing (3e). The outer profile of the fixed ring portions (4) incorporates post recesses (4d) which suitably interact with the socket body incorporated posts (3f) to prevent any movement between the socket body housing (3e) and the fixed ring potions (4). The rotatable ring portion (2) in this embodiment incorporates posts (2f) and recesses (2g) which interact with the socket body incorporated posts (3f) and rotatable ring recesses (3g) allowing the rotatable ring portion (2) to rotate within the socket

body housing (3e) inner recess (3c) within the confines of the said posts (2f, 3f). In this embodiment the drive spigot recess (3d) is shown to be a known square drive.

Figs 8a, 8b, 9a, 9b and 9c illustrate a fifth embodiment of a socket (1) for a wrench, which operates in the same general manner to that shown in Figs 6a and 6b. As shown in Fig 8a when in the unoperated or at-rest position, the fastener drive surface (2b) of the rotatable ring portion (2) is generally aligned with the fastener drive surfaces (4b) of the fixed ring portion (4). A positioning pin (12) within a positioning pin slot (3i) enables manual alignment of the fastener drive surfaces (2b, 4b). The unoperated or at-rest position is visually indicated by a position mark (3h). The fixed ring portions (4) are held either side of the rotatable ring portions (2) within the socket body housing inner recess (3c). The outer profile of the fixed ring portions (4) incorporates post recesses (4d) which suitably interact with the socket body incorporated posts (3f) to prevent any movement between the socket body housing (3 c) and the fixed ring portions (4). hi this embodiment the rotatable ring portion (2) said incorporated posts (2f) and recesses (2g) interact with the socket body incorporated posts (3f) and said rotatable ring recesses (3g) to allow the rotatable ring portion (2) to rotate within the said socket body housing inner recess (3c) within the confines of the posts (2f, 3f). As illustrated in Figs 9b and 9c, in this embodiment the rotatable ring portion (2) is rotatable is rotatable in both drive directions (D) from the unoperated or at-rest position shown in Fig 9a. hi this embodiment the fastener drive surfaces (2b, 4b) are generally convex. For illustration purposes the outer fixed ring portion (4) is not shown in Figs 9a, 9b and 9c.

The fourth and fifth embodiments shown in Figs 7a to 9c can be modified by reducing the length of three of the posts (3f) such that those posts do not extend to the free end (3j) of the housing inner recess (3c). The reduction in length of the three posts (3f) provides a seating for the outermost of the fixed ring portions (4b). The length of the three shortened posts (3f) should be such that the inner fixed ring portion (4b) and the rotatable ring portion (2) can fit behind the outermost fixed ring portion (4b) with sufficient clearance to allow the rotatable ring portion to rotate. Using this arrangement simplifies manufacture by providing a set clearance for the rotatable ring portion (2b) that will not be affected by the fixing of the outermost ring portion (4b) in the inner housing recess (3 c). The outermost fixed ring portion (4b) can be secured in the housing inner recess (3 c) by, for example, crimping or welding.

It will be understood that the fourth and fifth embodiments shown in Figs 7a to 9c can be modified by providing a greater number of rotatable ring portions (2) and fixed ring portions

(4). For example, there could be a total of five or seven portions (2) and (4) disposed in the housing inner recess (3c). As shown in Figs 7b and 8b, the ring portions (2) and (4) preferably alternate. Thus in a seven ring portion arrangement, an innermost fixed ring portion (4) would be located at the inner end of the housing recess (3 c) followed by a rotatable ring portion (2), another fixed ring portion (4), another rotatable ring portion (2), yet another fixed ring portion (4), yet another rotatable ring portion (2) and an outermost fixed ring portion (4). As previously described, the outermost fixed ring portion (4) preferably seats on the ends of a number of shortened posts (3f).

In modifications of the fourth and fifth embodiments in which the outermost fixed ring portion (4) seats on the ends of a number of shortened posts (3f), the number of post recesses (4f) provided in the outermost fixed ring portion may be reduced in number to take account of the number of shortened posts (3f). Thus, if number of posts (3f) that are shortened is three, the outermost ring portion (4) has three fewer post recesses (4f) than any other fixed ring portion (4).

It will be appreciated that features of the illustrated embodiments may be combined to form new embodiments. For example, the offset feature shown in Figs.όc and 6d can be incorporated in either of the embodiments shown in Figs 7a to 9c, so increasing the number of fastener head drive (9a) sizes the sockets (1) can usefully operate. This can be achieved by offsetting the respective axes of the apertures that define the fastener drive surfaces (2b), (4b) such that as the rotatable ring portion (2) rotates relative to the fixed ring portions (4) the fastener drive surface (2b) effectively makes a translational movement with respect to the fastener drive surfaces (4b).

In the embodiments, the sockets (1) each have one or more rotatable ring portions (2) sandwiched between parts (3), (4) or (7) that define fixed fastener drive surfaces (3b), (4b) or (7b) fixed. This is not essential. The socket may comprise just one rotatable ring portion cooperating with just one fixed fastener drive surface (3b), (4b) or (7b). As shown in Figs 1 and 2, the fixed fastener drive surface can be formed in the socket body portion (3) or, as shown in Figs 7a and 8a, the fixed fastener drive surface can be formed in a separate generally annular member fitted to the socket body portion.

It will be appreciated that when used in a wrench with an integral fixed handle as shown in Figs 3 and 4, the drive direction is easily reversed by the flipping or turning the wrench through 180°.

It will be understood that the fastener drive surfaces of the socket may be configured to allow a wide variety of size of fasteners to be operated by the same socket. For example, the fastener drive surfaces can enable the operation of both an as new 19mm A/F fastener head and when fully operated an as new 16mm A/F fastener head. Thus the socket can operate across a range of fastener sizes. In an another example a socket (1) can be configured such that unoperated the fastener receiving space is effectively 17mm A/F (across / flats) and approximately 19.8mm widest across the corners and by rotation of the rotatable portion can be adjusted to 17mm widest across the corners, which is equivalent to 14.65mm A/F.

The or each rotatable ring portion of the socket can be made capable of rotating in both directions from a mid at-rest or unoperated point (for example. 30° in either direction). This makes the socket capable of operating undersized fasteners (within it's size limitations) in either rotational direction so that it can be used for both tightening and undoing such a fastener.

It will be appreciated that the illustrated embodiments provide a socket that can be used to remove worn or damaged fasteners. When engaged upon a worn fastener drive surface, the rotatable ring portion is preferably held still while the socket is rotated. As the socket is rotated, its fastener drive surfaces come into contact with any undulations left on the fastener drive surface in an ever-tightening manner until locked upon the fastener drive surface. Any further torque applied to the socket is transmitted to the fastener to turn the fastener.