A tool for a plumbing connector

Abstract

Disclosed are examples of a spanner / ratches / wrench 100 for use with plumbing connectors C. These have features to prevent too much torque from being applied to a connector. There are mechanisms for indication to the user that the torque applied has exceeded a desired limit. There are features which prevent torque from being applied in the wrong direction. There are features which provide a simple engagement / disengagement with the connector. Also disclosed is a combination of these tools 100 with a generally circular connector C.

Description

[0001] A TOOL FOR A PLUMBING CONNECTOR

[0002] The present disclosure relates to tools for plumbing connectors or fittings. For example, it is concerned with a tool which is suitable for use in a plastic plumbing connector, particularly for use in the commercial plumbing environment. The Applicant has developed a new type of connector, which forms the subject of co-pending applications GB

[0003] 2011438.5, GB2011440.1 . These relate to a plastic locking cap to be rotated onto a body thereby compressing a collet against the pipe to be connected.

[0004] The locking cap can be rotated by hand. However, a tool may be used in order to generate the necessary torque. In such a case, it is important that the tool is not capable of generating too high a level of torque as this could result in over-tightening of the locking nut which could potentially damage the connector.

[0005] We are aware of a product for a part of the George Fischer Sanipex MT range which discloses a spanner with a pair of jaws which are biased to a closed configuration. In order to remove the spanner from the connector to which they are applied, it is necessary to slide the spanner axially along the connector as the adjacent pipework is a smaller diameter than the connector and there is then sufficient clearance to remove the spanner in this region. This limits the application of the connector as it can only be used where there is sufficient clearance adjacent to the connector to allow the spanner to be slid axially from the connector.

[0006] According to a first aspect of the disclosure, there is provided spanner for a connector, the spanner comprising a handle extending in a longitudinal direction and a head defining a substantially part circular cavity with an entrance in a closed configuration in which the width of the entrance is less than the maximum diameter of the cavity, the cavity having an entrance opposite to and facing away from the handle to receive a connector, the head comprising a pair of jaws which are biased together by a resilient member, such that when the spanner is moved longitudinally onto the connector, the jaws are separated against the action of the resilient member to allow the connector to enter the cavity, a thumb lever on one of the jaws, the thumb lever being positioned such that pressure on the thumb lever causes the jaws to move apart against the action of the resilient member from the closed configuration in which the width of the entrance is less than the maximum diameter of the cavity to an open configuration in which the jaws open out such that the width of the entrance is greater than the maximum diameter of the cavity in the closed configuration.

[0007] The present disclosure provides a spanner with jaws which are biased closed, but which can be opened by thumb lever so that, that they can be removed from the connector in the longitudinal direction.

[0008] One of the jaws may be provided with teeth facing the cavity and the other is not. This makes it easier to disengage the spanner form the connector as one side of the head can be disengaged without fear of snagging the teeth.

[0009] The inner profiles of the jaws may have a partially curved configuration which has the radius of curvature of the part circular cavity. This helps provide an intimate engagement wit ha curved connector.

[0010] The inner profiles of the jaws may have a curved inner profile, the curved inner profile extending for more than 180° of the circumference of the cavity, the angle at the centre of the cavity in the closed configuration being measured from one end of the curved inner profile to the other. Again, this helps provide an intimate engagement with a curved connector.

[0011] Each of the jaws may have a curved inner profile extending from the entrance of the cavity. Again, this helps provide an intimate engagement with a curved connector.

[0012] The head may be pivotally connected to the handle about a transverse axis which is parallel to the axis of rotation of the head, the head being biased in an operational position with respect to the handle by a spring loaded latch configured to release the head to pivot with respect to the handle about the transverse axis when the torque on the spanner exceeds a pre-determined threshold. This provides a tactile indication of overtightening.

[0013] The first aspect also applied to a combination of the spanner and a connector, wherein the spanner may be dimensioned such that the spanner can be applied to and disconnected from the connector by depression of the thumb lever and movement of the spanner in the longitudinal direction. The connector may have a substantially circular outer face in which a number of recesses are formed, wherein the inner profile of the cavity of the spanner follows the curvature of the substantially circular outer face and has teeth which are complementary with the recesses.

[0014] The locking cap on plumbing connectors is rotatable in a first direction through a limited number of turns to lock the connector. However, if the locking cap is accidentally rotated in the wrong direction, this can cause damage to the connector.

[0015] According to a second aspect of the disclosure, a combination of a spanner and a connector, the spanner comprising a handle extending in a longitudinal direction and a head defining a cavity, the head comprising a pair of jaws which are biased together by a resilient member to urge the jaws into a closed position surrounding a connector, at least one of the jaws having teeth which, in use, engage with complementary grooves in the connector, a first engagement feature on the head which is complementary with a second engagement feature on the connector, such that, when the spanner is placed onto the connector in a first orientation, the engagement features do not engage and prevent the jaws from fully closing, thereby preventing the teeth from entering the grooves, so that the spanner will slip around the connector, and when the spanner is placed onto the connector in a second orientation opposite to the first orientation, the engagement features engage to allow the jaws to fully close, so that the spanner can rotate the connector.

[0016] With this combination, if the spanner is used in the incorrect (first) orientation, the teeth are held out of the grooves and the spanner will slip around the connector. This prevents the spanner from being used to rotate the locking cap in the wrong direction thereby avoiding damaging the connector.

[0017] The first engagement feature may comprise a pair of longitudinally spaced circumferential protrusions on the head, and the jaws extending longitudinally partially between the circumferential protrusions in a manner which is not symmetrical about a median plane between circumferential protrusions; and the second engagement feature may comprises a pair of shoulders on the connector which engage with the circumferential protrusions to limit longitudinal movement of the spanner with respect to the connector, and grooves extending longitudinally partially between the shoulders in a manner which is not symmetrical about a median plane between shoulders and which is complementary to the jaws when the spanner is on the connector in the second orientation. This prevents the spanner being used in the wrong orientation, while providing a robust engagement when used in the correct orientation.

[0018] The teeth may have an asymmetric configuration such they can only drivingly engage in the grooves in one rotational direction. This makes it easier for the spanner to slip when used in the incorrect orientation.

[0019] A spanner may be provided for the combination of the second aspect, the spanner comprising a handle extending in a longitudinal direction and a head defining a cavity, the head comprising a pair of jaws which are biased together by a resilient member to urge the jaws into a closed position surrounding a connector, at least one of the jaws having teeth which, in use, engage with complementary grooves in the connector, and a first engagement feature in the form a pair of longitudinally spaced circumferential protrusions on the head, and the jaws extending longitudinally partially between the circumferential protrusions in a manner which is not symmetrical about a median plane between circumferential protrusions.

[0020] The spanner may have the optional features referred to above.

[0021] According to a third aspect of the present disclosure, there is provided a spanner comprising a handle extending in a longitudinal direction and a head defining a substantially part circular cavity with an entrance opposite to the handle to receive a connector, the head comprising a pair of jaws which are biased together by a resilient member, the jaws being relatively movable apart against the action of the resilient member from a closed configuration in which the width of entrance is less than the maximum diameter of the cavity in the closed configuration to an open configuration in which the jaws open out such that the width of the entrance is greater than the maximum diameter of the cavity in the closed configuration, the jaws having an inner profile which, when fitted to a connector with a complimentary outer profile is such that movement of the ratchet spanner in the longitudinal direction causes the jaws to move to the open position such that the spanner can be removed from the connector in the longitudinal direction.

[0022] The third aspect provides a spanner with jaws which are biased closed but which can be opened to a sufficient extent by interaction of the inner profile of the jaws with a connector, that they can be removed from the connector in the longitudinal direction. This provides a benefit over the above prior art arrangement, in that any connector to which the spanner is applied does not now need to have sufficient axial clearance for the spanner to be slid axially off of a connector before being removed as it can be removed directly from the connector by movement in the longitudinal direction.

[0023] Optionally the head is pivotally connected to the handle about a transverse axis which is parallel to the axis of rotation of the head, the head being biased in an operational position with respect to the handle by a spring loaded latch configured to release the head to pivot with respect to the handle about the transverse axis when the torque on the spanner exceeds a pre-determined threshold.

[0024] This notification could be an audible signal caused by a mechanism within the handle producing a “click” as the handle rotates relative to the head. However, alternatively, once the threshold value is exceeded, the handle is optionally configured to pivot through a noticeable angle, optionally greater than 5° with respect to the head such that it is immediately noticeable simply from the feel of the tool that the end point has been reached. This is particularly beneficial as the connector may be being installed on a noisy site such that a non-audible indication will be more reliable. The angle is optionally less than 15°, as with too large an angle, the sudden movement may cause a user’s hand to hit a nearby object.

[0025] Optionally the biasing force on the jaws is lower than the biasing force on the latch. This ensures that the head will not move with respect to the handle while the spanner is in normal operation with the ratchet mechanism being employed.

[0026] At least one of the jaws, possibly both, may be provided with ratchet teeth on its inner profile. This disperses the force around the connector making the tightening process easier and reducing the chance of damaging the connector.

[0027] The inner profiles of the jaws may have a partially curved configuration which has the radius of curvature of the part circular cavity. This provides for close engagement with a substantially circular connector. Conventional spanners have a plurality of flat faces to engage with the flat faces of a hexagonal hut.

[0028] The inner profiles of the jaws may have a curved inner profile, the curved inner profile extending for more than 180° of the circumference of the cavity, the angle the angle at the centre of the cavity in the closed configuration being measured from one end of the curved inner profile to the other. This provides for close engagement with a significant proportion of a substantially circular connector.

[0029] Each of the jaws may have a curved inner profile extending from the entrance of the cavity. Again, this helps to provide a close engagement with a significant proportion of a substantially circular connector.

[0030] The present disclosure also extends to a combination of the above spanner and a connector, wherein the connector and spanner are dimensioned such that the spanner can be applied to and disconnected from the connector by movement of the spanner in the longitudinal direction.

[0031] The connector may have a substantially circular outer face in which a number of recesses are formed, wherein the inner profile of the cavity of the spanner follows the curvature of the substantially circular outer face and has teeth which are complementary with the recesses. This helps to provide a close engagement with a significant proportion of a substantially circular connector.

[0032] The present disclosure also extends to a method of removing the spanner from a connector, the method comprising applying a force to the spanner in a longitudinal direction away from the connector such that interaction between the spanner and the connector forces the jaws of the spanner apart to a sufficient extent that the spanner is removed from the connector by movement only in the longitudinal direction.

[0033] The connector may have a substantially circular outer face in which a number of recesses are formed, wherein the inner profile of the cavity of the spanner follows the curvature of the substantially circular outer face and has teeth which are complementary with the recesses.

[0034] According to a fourth aspect of the present disclosure, there is provided an open-ended ratchet spanner comprising a handle connected to a head, the head defining a socket having defining a cavity to receive a connector, a plurality of spring clips fixed into the wall of the socket facing the cavity, each spring clip mounted such that, in an unstressed state, one end of the spring clip protrudes at an angle into the cavity such that its end face can engage with a recessed feature on the connector to turn the connector when the spanner is rotated about an axis of rotation in the first direction, sufficient clearance being provided behind the end of the spring clip such that it can be resiliently displaced out of the cavity by rotation of the spanner about the axis of rotation in a second direction opposite to the first direction..

[0035] A standard open-ended ratchet spanner is designed with a single spring loaded pawl and is designed such that as much as the socket of possible engages with the object.

[0036] By contrast, according to the present disclosure, it is the end faces of a plurality of spring clips which engage with the connector. These provide a ratchet-like engagement as the spring clips are displaced out of the cavity by rotation of the spanner in the second direction. Distributing the force in this way can help to reduce or prevents localised damage caused by the concentration of the force in a single position. Further, because only the end faces of the spring clips engage with a connector, the amount of force being applied to the connector can be controlled such that it is at a level which will reduce the occurrence of or prevent over-tightening. The spring clips can be configured such that, in the event of excessive force being applied, they will deflect outwardly, thereby slipping out of engagement with the connector. The spanner thereby provides the tool which can readily be used in a commercial plumbing environment where the ratchet mechanism will help a user to tighten the connector in areas where the connectors are relatively inaccessible.

[0037] This compares very favourably with conventional commercial plumbing press-fit connectors which require power tools in order to compress the connector onto the pipe. This can allow for connections to be made in tighter spaces and therefore means that, as well as being easier to use, smaller volumes can be set aside for the pipe and connector.

[0038] Although specifically designed for the above-mentioned plastic commercial plumbing connector, the spanner can be used in any environment, particularly when a limited torque is required.

[0039] In a conventional spanner, the entrance to the cavity is the widest point of the cavity so that the spanner can be engaged with the object in a lateral direction. However, with a commercial plumbing connector, the connector has a larger diameter than the pipe to which it is connected. This allows the spanner to be engaged with the connector by being first moved in a lateral direction to surround the pipe and then being moved in a longitudinal direction to engage with the connector body. Thus, the opening of the cavity only needs to be wide enough to fit over the pipe, not over the connector. Therefore, optionally, the entrance to the cavity is narrower than the maximum diameter of the cavity. As a result of this, the head can engage with a greater portion of the circumference of the connector. This provides for a greater dispersion of force around the connector as it allows a larger number of spring clips to be used. This higher number of clips allows each individual clip and its mounting to be smaller as each one is required to provide a lower level of torque. As such, this allows the outer profile of the head to be reduced, thereby improving the accessibility of the tool into confined spaces.

[0040] Each spring clip may have a generally V configuration, with one arm having the one end protruding into the cavity and the other arm being embedded within the head to anchor the clip in place. In the unstressed state, the one arm is optionally supported by the head other than in the region adjacent to the one end to reduce the possibility of the spring clip buckling and / or being plastically deformed by a user apply excess torque to the tool.

[0041] In order to further enhance the flexibility of the tool, the handle and head are optionally pivotally connected together to allow the angle of the head to be adjusted with respect to the handle about a pivot axis transverse to the axis of rotation. Normally this would be counter-intuitive in a spanner as the handle and head should be coplanar in order to maximise the torque which can be applied by the head. However, in the present case, because the spanner does not need to apply such high levels of torque, the pivotal connection between the head and handle enhances the flexibility of the tool while still being able to provide the desired levels of torque.

[0042] The pivotal connection between the handle and head may, for example, be a relatively stiff connection which does not have any fixed positions. Optionally, however, a catch mechanism is provided between the handle and the head to selectively lock them in a number of different relative angular positions. The latch mechanism may comprise a spring loaded plunger on one of the handle or head configured to cause selective engagement with a plurality of teeth on the other of the handle or head which are arranged about the pivot axis such that the latch can selectively engage between different teeth to lock the handle and head in different angular configurations. This provides a mechanism which is very easy to use as the user simply needs to operate the spring loaded plunger, adjust the handle and head, and release the plunger at the desired angle. The selective engagement of the plunger with the teeth may be direct engagement of the plunger on the teeth or may be via an intermediate component such as a ball. According to a fifth aspect of the present disclosure, there is provided an adjustable wrench comprising two parts pivotally connected to each other, each part having a jaw on one side of the pivotal connection and a handle on the opposite side of the pivotal connection, one of the parts having a slot and the other having a pivoting element slidable along the slot to vary the position of the pivot axis; a variable stop between the handles, arranged such that a degree to which the handles can approach one another differs depending on the position of the pivot axis; wherein the inner face of each jaw is provided with at least one resilient element for engaging with an object to be gripped..

[0043] This adjustable wrench has a number of features which make it suitable for the above- mentioned plumbing connectors. Because the pivot axis is adjustable, the wrench is able to engage with connectors of different diameters, so that it does not require a separate tool for each size of connector. However, the variable stop ensures that, for each size of connector, the degree to which the handles can approach one another is controlled to an extent such that the jaws cannot be over-tightened on the connector.

[0044] This degree of engagement is set such that the resilient element is partially compressed. This partial compression of the resilient element ensures that a reliable and well defined gripping force is provided on the connector as the application of excessive torque causes the resilient element to slip over the connector, thereby reducing or preventing over- tightening. Further, the fact that the degree of closing of the jaws is limited reduces or prevents the possibility of crushing the connector.

[0045] There may be a single resilient element on the inner face of each jaw. The resilient element may be provided as a number of protuberances arranged around the inner face of each jaw. These protuberances may either discrete resilient elements, or there may be single resilient element with an undulating profile to provide the protuberances. With such an arrangement, when the wrench is set to engage with a smaller diameter connector, only certain of the protuberances will be engage with a connector, while, for a larger diameter connector, all of the protuberances will engage with a connector. This provides a way of controlling the force applied to a different diameters of connector which does not rely solely on the degree of compressibility of the resilient elements, but instead is able to vary the degree of contact between the resilient elements and the connector depending on the size of the connector. Optionally, the wrench is provided with a number of indicia which are selectively automatically displayed depending upon the position of the pivot axis. This can provide an indication of the size of the connector to which a particular configuration of the wrench can be applied.

[0046] The variable stop may be in the form of a lug on one of the handles which projects towards the other handle and a series of steps of different heights on the adjacent handle, the lug being positioned such that it is selectively aligned with one of the steps depending upon the position of the pivot axis. This provides a simple way of creating the variable stop as it is provided by features which are built into the handle, and which is fail safe in the sense that the position of the variable stop is determined by the position of the pivoting element within the slot.

[0047] Examples of spanners and adjustable wrenches in accordance with the various aspects of the invention will now be described with reference to the accompanying drawings, in which:

[0048] Figure 1 is partially sectioned plan view of the first example of an open-ended ratchet spanner of the fourth aspect in place on the connector;

[0049] Figure 1 A is a detailed view of the area shown in circle A in Figure 1 ;

[0050] Figure 1 B is a view similar to Figure 1 A showing the spanner in the different rotational position relative to the connector;

[0051] Figure 2 is a partially sectioned perspective view of the spanner of Figure 1 ;

[0052] Figure 3 is a perspective view of the spanner of Figure 1 with the handle and head in a first configuration;

[0053] Figure 4 is a view similar to Figure 3 with a handle and head in a second configuration;

[0054] Figure 5 is a plan view of part of the spanner of Figure 1 showing the detail in the interface between the handle and head; Figure 6 is a partial and cross-sectional view of the spanner of Figure 1 in a plane transverse to the plane of sectioning in Figure 1 showing the same part of the spanner as Figure 5;

[0055] Figure 7A is a cross-sectional plane in the same plane as Figure 6 showing the whole spanner with the handle and head in a third configuration;

[0056] Figure 7B is a view similar to Figure 7A showing the handle and head in the first configuration;

[0057] Figure 8 is an exploded perspective view of the spanner of Figure 1 ;

[0058] Figure 9 is a perspective view of the spanner of Figure 1 showing the head in exploded view;

[0059] Figures 10A to C show the manner in which the first spanner is applied to the connector,;

[0060] Figure 11 is a perspective view of a second example of a ratchet spanner in a first configuration;

[0061] Figure 12 is a cross-sectional view of the head of the spanner of Figure 9;

[0062] Figure 13 is an exploded perspective view of the second spanner of the fourth aspect;

[0063] Figure 14 is an exploded perspective view of a third example of a spanner of the fourth aspect;

[0064] Figure 15 is a perspective view of the third spanner in a plane which is at 90° from that of Figure 14 with the head and socket in a first configuration;

[0065] Figure 16A is a cross-section of the third example in the plane perpendicular to the main plane with the handle and head in a second configuration.

[0066] Figure 16B with a view similar to Figure 16A with the handle and head in the first configuration of Figure 14; Figure 17 is a plan view of a first adjustable wrench of the fifth aspect in a first configuration;

[0067] Figure 18 is a plan view of a first adjustable wrench of the fifth aspect in a second configuration;

[0068] Figure 19 is a plan view of a first adjustable wrench of the fifth aspect in a third configuration;

[0069] Figure 20 is a plan view of a first adjustable wrench of the fifth aspect in a fourth configuration;

[0070] Figure 21 is a perspective view of a spanner of the third aspect shown engaged with a coupling;

[0071] Figure 22 is a plan view of the head and part of a handle of the spanner of the third aspect;

[0072] Figure 23 is a side view of the spanner of the third aspect engaged with a coupling;

[0073] Figure 24 is a cross-section through a main plane of the spanner of the third aspect showing the head and handle in a first configuration;

[0074] Figure 25 is a view similar to Figure 24 showing the head and handle in a second configuration;

[0075] Figure 26 is a cross-sectional view showing the head of the spanner of the third aspect engaged with a connector;

[0076] Figure 26A shows the detail in circle A in Figure 26.

[0077] Figure 27 and 27A are views similar to 26 and 26A respectively showing the head partially decoupled from the connector; and

[0078] Figure 28 is a plan view of the spanner of the third aspect showing the spanner almost fully uncoupled from the connector; Figure 29 is a longitudinal cross-section with a spanner of the first and second aspects with the head in a first configuration;

[0079] Figure 30 is a view similar to Figure 29 with the head in a second configuration;

[0080] Figure 31 is a plan view similar to Figure 29 showing the spanner engaged with a connector;

[0081] Figure 32 is a view similar to Figure 31 showing the jaws in an open position;

[0082] Figure 33 is a view similar to Figure 32 with the spanner partially withdrawn from the connector;

[0083] Figure 34 is a cross-sectional view of a connector and the head and part of the handle of the spanner of the first and second aspects with the jaws in a fully engaged position;

[0084] Figure 34A shows in the detail in circled A in Figure 34;

[0085] Figure 35 is a view similar to Figure 34 with the jaws not fully closed;

[0086] Figure 35A shows the detail circled A in Figure 35;

[0087] Figure 36 is a perspective view with the spanner of the first and second aspects positioned on a connector;

[0088] Figure 37 is a cross-sectional view through part of the connector and head with the components in a position in Figure 34;

[0089] Figure 38 is a view similar to Figure 36 showing the spanner in the incorrect orientation;

[0090] Figure 39 is a view similar to Figure 37 with components in the position in Figure 38;

[0091] Figure 40 is a plan view of one of the jaws;

[0092] Figure 41 is a side view of the locking sleeve of the connector; Figure 42 is a perspective view of the head in a position shown in Figure 36;

[0093] Figure 43 is a cross-section of the same plane and the same orientation as Figure 35 but is showing the spanner in the incorrect orientation.

[0094] Examples of open-ended ratchet spanners of the fourth aspect are described in Figures 1 to 16. All of these use essentially the same socket configuration, but differ in the manner in which the handle is connected to the head. The common description of the socket will first be described below, before the separate different connections between the handle and the head of the three examples are described.

[0095] The spanner has a handle 1 and a head 2. The head 2 defines a socket 3 which has a generally part circular configuration which is sized to receive a connector C. In this case, the socket has been designed for a plumbing connector C or fitting which has an internal screw thread T and a number of axial grooves G on its outermost cylindrical surface.

[0096] The mouth of the socket 3 is narrower than the maximum diameter of the socket such that the head 2 extends around approximately three quarters of the circumference of the connector C.

[0097] As indicated in Figure 9, the head 2 is formed of a main body 4 and a cap 5. The main body 4 is provided with a plurality of recesses 6 which are partially filled with projections 7 on the cap 5 as best shown in Figures 1 A and 1 B. Within each recess 6 is a spring clip 8 having a generally V shape cross-section as best shown in Figures 1 A, 1 B, and 9. An inner arm 9 of each spring clip 8 is held in place by being disposed, e.g., sandwiched, between the projection 7 and the main body 4. The cap 5 is attached to the body 4 by the screws 10 and nuts 11 shown in Figure 9.

[0098] Once held in place, an outer arm 12 of each spring clip 8 will protrude slightly at an angle into the socket 3 as is apparent from Figure 1A. In this position, part of the outer arm 12 is supported by a wall 13 formed by part of the main body 4.

[0099] The spanner is applied to the connector as shown in Figures 10A to 10C. The spanner cannot fit transversely onto the connector C as the mouth of the socket 3 is too small. As shown, the spanner is presented to the pipe P axially away from the connector. It is then moved axially onto the connector C to the position shown in Figure 10C. When the spanner is applied to the connector shown in Figures 1 and 2, an outer end 14 of the outer arm 13 of each spring clip 8 will drop into a complimentary groove G in the connector C. As can be see, for example, from Figure 2, the spacing of the spring clips 8 is configured so that all of the spring clips 8 simultaneously engage with a groove G in the connector. In this case, the spacing of the spring clips 8 is twice the spacing of the grooves G so that the spring clips 8 engage in alternate grooves G, although this can be varied.

[0100] Rotation of the head 2 in a first direction, as depicted arrow 15 in Figures 1A, 2 and 10C, causes the outer end 14 of each spring clip 8 to push against a complimentary surface in the groove G thereby rotating the outer part of the connector G to tighten the screw thread T against an underlying component (not shown).

[0101] When the head 2 is rotated in the opposite direction, as depicted by the arrow 16 in Figures 1 B, 2 and 10C, the spring clips 8 have a ratchet-like effect in that the spring clip is pushed, by an outer wall W of the connector C away from the grooves G into the recess 6 in the manner shown in Figure 1 B thereby allowing the head 2 to rotate freely with respect to the connector C, producing a ratchet-like effect. The rotational direction of the head 2 is then reversed to further tighten the connector as described above in relation to Figure 1 A, and the process is repeated until the connector C is tightly made up.

[0102] The connector C may be provided with end-stop features which prevent over-tightening, or the user may simply experience a high resistance to further tightening. Either way, it is desirable that the spanner cannot apply further torque to the connector C which might damage the connection.

[0103] As will be appreciated from the above explanation, the torque is applied via the outer ends 14 of a small number of spring clips 8 onto grooves G within the connector C. As such, the connector C is inherently incapable of applying the level of torque associated with a traditional spanner in which flat surfaces within the spanner engage with complimentary flat surfaces on the object.

[0104] The effect of the application of excess torque can be appreciated from Figure 1A. Once the connector C can no longer rotate easily with respect to the head, further attempted movement in the first direction 15 begins to stress the outer arm 12 of each spring clip 8 which will cause this arm to buckle, thereby dislodging the outer end 14 from the groove G at which point the head 2 will slip with respect to the connector C thereby preventing further tightening.

[0105] The head thereby provides a simple, but effective way of applying relatively low levels of torque to a connector C in a well distributed manner around a connector and in a manner which will prevent unwanted tightening. As such, it is well adapted for a plumbing connector, or any other application where such performance is desirable. The fact that the spring clips 8 are distributed around a significant proportion of the head, reduces any localised stresses such that the width of the head 2 can also be kept relatively small. This allows connectors C to be deployed in relatively confined locations.

[0106] As a further way of improving accessibility to the connectors C, the handle 1 is pivotally attached to the head 2. The first way in which this is achieved will be described with reference to Figures 1 to 9.

[0107] The handle 1 is connected to the head 2 by a pivot pin 20 which passes through a pair of holes 21 on the handle 1 and a central hole 22 formed of on a boss 23 which fits onto the handle between the two holes 21 . The boss 23 is provided with an array of teeth 24, as best shown in Figure 6 which are arranged in an arc about the axis of the pivot pin 20. The handle 1 has a plunger 25 which is biased by a spring 26 towards the boss 23 such that the end 27 of the plunger is urged into a gap between adjacent teeth 24, thereby allowing the handle 1 to be fixed in different angular positions with respect to the head 2, as shown in Figures 3, 4, 7A and 7B. The plunger is manually retracted by a button 28 which is fixed to the plunger 25 as shown in Figure 6 and slidable within a groove 29. This provides a simple mechanism by which a user can adjust the head with respect to the handle in order to provide a more convenient position to use the tool on a connector C that may be difficult to reach. The mechanism even allows for the angular position of the handle 1 with respect to the head 2 to be changed after the head 2 is engaged with the connector C simply by the user operating the button 28 to withdraw the plunger, altering the angular position, and releasing the plunger to lock the tool in the appropriate configuration.

[0108] As shown in the Figures, the handle has approximately 45° of movement either side of the median plane. The greater the angle from the median plane, the more difficult it becomes to transmit the necessary torque to the head. A second example of the spanner is shown in Figures 11 to 13. This has the same socket arrangement as described above and this will not be described again here. The only difference concerns the manner in which the handle 1 is pivotally attached to the head 2.

[0109] In this case, the head 2 is provided with a pair of projecting bosses 30 with through holes 31 . The handle 1 has a single boss 32 with a through hole 33 which aligns with the holes 31 to receive a pivot pin 34. The boss 32 is provided with an array of teeth 35 arranged about the pivot pin 34. An actuation button 36 is received in a stepped bore 37 and is coaxial with the pivot pin 34. The button 36 is spring loaded by a spring 38 which urges it outwardly to the position shown in Figures 11 and 12 in which its end projects from the head 2. The button 36 has a recess 39 part way along its length. A ball 40 is retained within the head 10 between the teeth 35 and the button 36 such that, in the position shown in Figure 12, the ball 40 prevents rotation of the handle 1 relative to the head 2 because the ball 40 cannot move out of a gap between adjacent teeth 35.

[0110] In order to rotate the handle 1 with respect to the head 2, the button 36 is depressed thereby allowing the ball 40 freedom to move into the recess 39 such that the handle 1 is free to rotate with respect to the head 2. Upon release of the button, the spring 38 urges the button 36 outwardly thereby returning it to the position shown in Figure 12 and locking the handle 1 with respect to the head 2.

[0111] The third example is shown in Figures 14 to 16B.

[0112] This uses the same socket arrangement as the previous two examples. Also, the features of the handle 1 and head 2 are similar to those described in relation to the second example and the same reference numerals have been used to denote the similar components.

[0113] In this case, the button 36’ is mounted transversely to the pivot pin 34. Otherwise, the arrangement is the same as previously described. As can be seen in Figure 16B, in a locked configuration and the ball 40 is again unable to move out of the gap between adjacent teeth 35 thereby locking the handle 1 with respect to the head 2. In order to adjust the angle, the button 36’ is depressed such that the ball 40 can move into the recess 39 providing freedom to rotate the handle 1 with respect to the head 2. The button 36’ is forced outwardly by the spring 38 (to the position shown in Figure 16B) thereby locking the position of the handle 1 with respect to the head 2. The adjustable wrench in accordance with the fifth aspect of the disclosure will now be described with reference to Figures 17 to 20.

[0114] The wrench is formed of a first part 50 and a second part 51 pivotally connected together by pivot element 52. The first part 50 has a handle 53 on one side of the pivot element 52 and a jaw 54 on the opposite side of the pivot element 52. Similarly, the second part 51 has a handle 55 on one side of the pivot element 52 and a jaw 56 on the opposite side of the pivot element 52.

[0115] In the vicinity of the pivot element 52, the first part 50 is forked such that it has a first connecting portion 57 and a similarly shaped spaced apart second connection portion (not shown) immediately behind the first connecting portion 57. The second part 51 passes between the first and second connecting portions 57 and the pivot element 52 then passes through the first and second connecting portions 57 and the second part 51 in order to pivotally attach the two parts.

[0116] Each of the jaws 54,56 are provided on its inner face with four resilient protrusions 58 which may, for example be made of rubber, which are evenly spaced around the inner faces of the jaws.

[0117] The handle 53 is provided with a projecting lug 59 facing towards the opposite handle 55. A series of steps 60-62 are provided on the handle 55 and extend progressively further towards the handle 53.

[0118] In the vicinity of the pivot element 52, the second part 51 is provided with a slot 63 that the pivot element 52 can slide along.

[0119] This allows the wrench to be operated in a plurality of different configurations, such as illustrated in Figures 17 to 20 respectively.

[0120] The second part 51 is marked with four numbers along the length of the slot 63. In this case, the numbers are “16”, “20”, “26”, and “32” and these correspond to the size of the connector C that can be received by the wrench when the pivot is aligned with that particular number. In the present case, the adjustable wrench can be used in four configurations as shown in Figures 17 to 20. Figure 17 shows the smallest configuration. In this case, the pivot element 52 is at the top end of the slot 63, this effectively means that the jaw 56 takes on its smallest configuration and the cavity between the jaws 54,56 is therefore at its smallest. The pivot element 52 has a window 64 which is aligned with the number “16” on the first part 51 indicating to the user that the wrench is in a configuration which is suitable for use with a connector C with an outer diameter of 16mm.

[0121] The wrench is presented to the connector and the jaws are closed into the position shown in Figure 17. In this case, just the two inner most protrusions 58 will grip the connector C and will be slightly deformed by this engagement.

[0122] Figure 18 shows the connector suitable for engaging with a slightly larger connector C’. In this case, the pivot element 52 has been moved one position along the slot 63 thereby displaying the number “20” and slightly enlarging the socket. With this slightly larger connector C’, it is still only the central protrusions 58 which engage with the connector C’. The movement of the pivot axis moves the lug 59 down one step such that it aligns with the second highest step 61 thereby preventing further tightening of the wrench.

[0123] Figure 19 shows the wrench engaging with the second largest connector C”. In this case, the pivot element is aligned with the number “26” and the lug 59 is aligned with the lowermost step 60. By now, all of the protrusions 58 engage with the connector C”.

[0124] Finally, the largest connector C’” is shown in Figure 20. The pivot element 52 has now reached the bottom of the slot 63 and the number “32” is displayed. The lug 59 abuts against the handle 55.

[0125] A number of variations to the design can be readily envisaged. For example, the second part 51 may be provided with the forked structure and the first portion 50 may pass through this. The pivot and slot 63 may be provided on the first part and the pivot mechanism adapted accordingly. The described example has four separate settings, but a greater or lesser number could be provided.

[0126] In place of the numerical indicia, a different system could be used. For example, there may be colour coded indicia which match a colour tag on the connector. In order to use the wrench, the operator sets the jaws into the position to match the diameter of the connector that they are working on. They then grip and rotate the connector. The resilient protrusions 58 engage with the connector in a manner which will grip the connector, but will not crush it given the resilience of the protrusions 58 and the fact that over compression of the jaws 54, 56 is prevented by the engagement of the lug 59 with the appropriate step 60-62 or with the handle 55 itself. In addition, any damage caused by overtightening of the connector, as opposed to crushing of the connector, is also avoided as the gripping force is tightly controlled by the degree to which the protrusions 58 are compressed and can be set to slip at a level which might otherwise damage the connector.

[0127] An example of the spanner in accordance with the third aspect will now be described with reference to Figures 21 to 28.

[0128] The spanner 100 comprises a handle 101 and a head 102 pivotally connected together as described in greater detail below.

[0129] The handle 101 comprises a shaft 103 with a grip 104 at the end opposite to the head 102. Within the shaft 103 is part of break over torque limiting mechanism. This comprises a plunger 105 slidably mounted within the shaft 103. The plunger 105 is biased towards the head 102 by a spring 106 which is supported at the opposite end by a bung 107.

[0130] The opposite end of the plunger 105 from the spring 106 carries a rotatable bearing member 108 which is axially moveable together with the plunger 105.

[0131] The remaining part of the over torque limiting mechanism is provided by the head 102. This is pivotally supported with respect to the handle 101 by a pin 109 for limited pivotable movement with respect to the handle 101 . The head 102 comprises a stub 110 which projects into the handle 101 and receives the pin 109. The stub 110 has a tapered shape as best shown in Figures 24 and 25. This allows it to move between a first configuration shown in Figure 24 in which the top of the stub 110 is supported by the handle 101 and a second configuration shown in Figure 25 in which the opposite surface of the stub 110 is supported against the handle 101.

[0132] The configuration shown in Figure 24 represents the normal operation configuration in which the spanner is applied to the connector and the connector is tightened. Once the connector is tightened to a sufficient extent that it is fully made up, a further effort to tighten the connector using the spanner increases the torque on the handle. This causes an increased rotational force on the head 102 about the pin 109 such that engagement of an end face 111 of the stub on the bearing member 108 urges the bearing member 108 to the right as shown in Figure 24 against the biasing force of the spring 106. Thus, if a user attempts to apply a torque in excess of a pre-determined amount, this force will overcome the biasing force of the spring 106 displacing the plunger 105 to the right and causing the head 102 to rotate to the position shown in Figure 25.

[0133] As can be seen in Figure 25, the angle a through which the head 102 has rotated relative to the handle 101 is a relatively large angle (around 20°), and this movement will happen abruptly once the force of the spring is overcome. Thus, the user is presented with a very clear and well-defined end point indicating that the connector has been fully made up. This end point indication does not rely on an audible alert so is particularly useful in a noisy environment.

[0134] When the user backs off from applying the excessive torque, the spring 106 will urge the bearing mechanism 108 to the left as shown in Figure 25 which has the effect of rotating the head 102 back to the operational position shown in Figure 24.

[0135] The head 102 will now be described in greater detail.

[0136] The head 102 comprises a first jaw 120 and a second jaw 121 which are pivotally connected together via a second pivot pin 122 and are biased together by the second biasing spring 123. The first jaw 120 is an extension of the stub 110, while the second jaw 121 is a separate component. As best shown in Figure 26, the spring 123 biases the jaw to a normal operating position in which the first abutment surface 124 on the first jaw 120 abuts against a second abutment surface 125 on the second jaw 121. This is shown in Figure 26 and is the operational position in which the jaws tightly engage with the connector and rotated.

[0137] The first jaw 120 is provided with a first plurality of teeth 126 which have a ramped configuration with an inclined face 127 and an end face 128 as shown in Figure 26A. The second jaw 121 has a second plurality of teeth 129 with a similar configuration. In a position shown in Figure 26, the end faces 128 of the teeth press against corresponding recesses in the connector such that when the head 102 is rotated clockwise, the connector C is rotated and tightened.

[0138] When the head is rotated anti-clockwise, the ramp faces 127 of the teeth cause the teeth to disengage from the recesses R such that the head can rotate in an anti-clockwise direction as shown in Figure 27 around the outer periphery of the connector until the teeth re-enter other recesses R allowing further tightening of the connector. As the teeth 126,129 leave the recesses R, and ride along the outer face of the connector, the first 120 and second 121 jaws are urged slightly away from one another, as represented in Figure 27 where the first 124 and second 125 abutment surfaces have separated slightly. The spring 123 then urges the jaws back the closed configuration shown in Figure 26 when the teeth 126, 129 re-enter the recesses R.

[0139] The spring 123 serves a further purpose in that it can allow further separation of the jaws 120, 121 beyond the position shown in Figure 27. This further position is represented in Figure 28 in which the jaws 120, 121 have opened to their fullest extent which is limited by engagement of a third abutment surface 130 on the stub 110 with a fourth abutment surface 131 on the second jaw 121.

[0140] In this configuration, the jaws have opened to such an extent that the gap G between the jaws 120, 121 is equal to or greater than the diameter D of the connector C. The diameter D is a measurement to the outermost wall of the connector C at a location away from the recesses R. As a consequence of this degree of opening, the spanner 100 can be applied to the connector C by moving only in the longitudinal direction L. This means that the spanner can be applied directly to the connector C at its widest point. It does not need to be initially placed over the pipe P and then slid axially onto the connector C. Once it has been moved further right from the position shown in Figure 28, the second spring 123 will cause the jaws to contract around the connector C into the position shown in Figure 26 or 27 depending on whether or not the teeth 126, 129 are reliant with the recesses R. The user can then tighten the connector C using the ratchet assisted tightening method described above. Once the connector is fully tightened, if the user attempts to tighten the connector C any further, the break over torque mechanism described above will come into play thereby indicating that the connector is fully tightened.

[0141] Once the connector is fully tightened, this can either be determined by the operation of the break over torque, or because the user determines this by other means, the spanner can then be withdrawn. This is done by pulling the spanner away from the connector C in the longitudinal direction L. This forces the jaws 120, 121 apart and the extent to which they are able to open, allows the gap G to be opened to a size which is at least as large as the diameter D of the connector C allowing the spanner to be removed.

[0142] The degree to which the jaws 120, 121 , can be opened simply by moving to the longitudinal direction L is a function of both the degree to which the jaws are allowed to separate as well as the ability of the jaws themselves to generate a cam force which is sufficient to allow the jaws to be opened widely enough to be removed in the longitudinal direction L.

[0143] By way of illustration, for example, even if the jaws were capable of opening to the required extent, if the teeth were particularly large and / or were not provided with a shallow ramp angle, the jaws would not be capable of opening to the required extent. Some external force will be required, for example, the jaws could be manually prized apart or they would have to be slid axially to a narrower part of the connector.

[0144] Thus, the geometry of the internal faces of the first 120 and second 121 jaws must be one which will enable to jaws 120, 121 to opening such that the gap G between the jaws 120, 121 is at least as large as the diameter D of the connector C within the jaws, when the connector C has a geometry which is complementary to that of the inner surface of the jaws 120, 121 . It will be appreciated that, in the illustrated example, the outer geometry of the connector C is not entirely complementary with that of the jaws 120, 121 in that the recesses R have a rectangular cross-section which is not complementary with the ramplike teeth 126, 129. However, the spanner is configured such that it is capable of removing itself from such a notional connector with a complimentary configuration purely by movement in the longitudinal direction L. Although this is dependent on both the extent to which the jaws can open and the internal profile of the jaw geometry (which would be complex to specify geometrically), this can easily be determined in practice by attempting to remove the spanner form a connector with a complementary profile by pulling the spanner in the longitudinal direction and determining whether this is sufficient to remove it.

[0145] The connector depicted in Figures 26 and 27 has first teeth 126 on the first jaw 120 and second teeth 129 and the second jaw 121. This helps to distribute the loads evenly around the connector C, thereby reducing any localised stresses. However, it is also possible that the teeth are present on only one of the jaws 120, 121. In Figures 24 and 25, no teeth are present on the first jaw 120. An example of the spanner in accordance with the first and second aspects will now be described with reference to Figures 29 to 43.

[0146] As is apparent from Figures 29 and 30, this example is a similar structure to the handle of the second aspect shown in.Figures 24 and 25 and has the same over torque limiting mechanism in the form of the bearing member 108 which cooperates with the stub 110. In this example, the angle of rotation has been reduced to 5° degrees as this is deemed sufficient to alert the user to the torque limit without causing large sudden movements of the handle.

[0147] The main differences of this example relates to the jaws 220, 221 . These have essentially the same shape as the jaws 120,121 of the previous example and are biased in the same way by the spring 223 about a pivot point 222.

[0148] In the close position shown, for example, in Figure 29, the surfaces 224 and 225 prevent further rotation of the jaws thereby defining the closed position shown in Figure 29. The first jaw 220 has essentially the same shape as the first jaw 120 of the previous example. In this case, the inner face of the jaw 220 has no teeth.

[0149] The second jaw 221 has the same basic shape as the second jaw 121 of the previous example and is provided with teeth 229 on its inner face.

[0150] An additional feature, of this example is the provision of a thumb lever 230 to the second jaw 221 . This extends back towards the handle 101 . As shown in Figure 32 a user is able to apply manual pressure on the thumb lever 230 pushing it towards the handle 101 thereby rotating the second jaw 221 about the pivot 222 against the biasing force of the spring 223. This causes the jaws to open to the position shown in Figure 32 allowing the spanner to be withdrawn from the connector C as shown in Figure 33.

[0151] In the previous example, the interaction between the geometry of the head and the connector provides sufficient opening for the spanner to be withdrawn. In the present example, the thumb lever 230 can be configured to open the jaws to a sufficient extent that the spanner can be withdrawn without relying on the interaction of the geometries of the head and connector. Alternatively, the thumb lever may be configured to open to jaws to a lesser extent such that the interaction of the geometry of the head and connector still plays some role in removing the spanner. The thumb lever 230 will therefore either eliminate or reduce the need to rely on the geometrical interaction and therefore reduces or eliminates the amount of manoeuvring required of the user in order to remove the spanner. The lever 230 is described as a thumb lever as it is positioned in a location which is convenient for a user to operate using their thumb. However, this is no reason why this lever should not be used by the user’s fingers or in some other way.

[0152] The manner in which the spanner 100 engages with the connector C will now be described.

[0153] As shown in Figures 36 to 39 and 41 , the connector C is provided with a raised feature 300 which is bounded by a first shoulder 301 and second shoulder 302. The shoulders 301 , 302 are axially spaced and generally parallel to one another. A plurality of axially extending blind slots 303 extend from the second shoulder 302 most of the way to the first shoulder 301 . As will be appreciated from the above Figures, the effect of the slots 303 is that the second shoulder 302 is intermittent while the first shoulder 301 is continuous. A raised portion 304 of material as is apparent from Figures 37, 39 and 41 remains between the end of the slot 303 and the first shoulder 301 .

[0154] Features on the connector C are complementary to the features of the jaws 220 and 221 as best shown in Figures 40 and 42. The first 220 and second 221 jaws are provided with a pair of circumferential upstanding parallel tracks, namely a first track 306 and second track 307. The first track 306 is at the side of the head which faces the pipe P while the second track 307 is on the opposite side of the connector. The spacing between the tracks 306, 307 is the same as the spacing between the first 301 and second 302 shoulders such that when they are fully engaged, the tracks 306, 307 fit closely against the shoulders 301 , 302. The spacing and shape of the teeth 229 on the second jaw 221 is complementary to the shape and spacing of the slots 303 in that the teeth 229 terminate short of the second track 307 as shown in Figure 42.

[0155] The jaws 220, 221 are provided with arrows 308 indicating the correct orientation for applying the spanner 100 the connector C. Once oriented the correct way round, the spanner 100 is applied longitudinally to the connector C. Movement of the spanner onto the connector causes the jaws to be spread against the action of the biasing spring 223 (as shown in Figure 33) until the spanner reaches the fully engaged position (Figure 31) when the spring 223 closes the jaws against the connector. In the event that the teeth 229 are not aligned with the blind slots 303, the user can rotate the spanner 100 to a small extent until alignment is achieved. In the fully engaged position, the first track 306 abuts against the second shoulder 302 and the second track 307 abuts against the first shoulder 301 . In this position, the teeth 229 are fully engaged in the slots 303 as shown in Figure 34A such that the connector C can be rotated in the clockwise direction in Figure 34 where the teeth 229 press on the side of the slots 303. Teeth can be provided on the first jaw 220 to achieve a similar effect as well as, or in addition to the teeth on the second jaw 221 . However, it has been found that the arrangement shown is sufficient to provide the necessary driving force for the connector C.

[0156] When the spanner 100 is rotated in the opposite direction (anti-clockwise in Figure 34), the asymmetric nature of the teeth 229 with the ramp face shown in Figure 34A means that the teeth will ride up out of the slot 303 causing the jaws to be separated slightly against the spring 223 (as shown in Figure 35) such that the spanner 100 will rotate around the connector before the spring 223 causes the teeth 229 drop back into slots 303 further round the connector and reengage with these slots to provide a ratchet effect.

[0157] The spanner 100 may be applied to the connector C in the opposite orientation and this is illustrated in Figures 38, 39 and 43.

[0158] In view of the configuration of the slots 303 and teeth 229, the teeth 229 can never fully enter the slots 303 as the raised portion 304, the raised feature 300 will always engage with the teeth 229 as shown in Figure 39. By contrast and correct orientation, the raised portion 304 fits, as shown in Figure 37, into the space between the teeth 229 and second rail 307.

[0159] As a result of this, the jaws 220, 221 cannot fully close and the teeth 229 enter the slot 303 as shown in Figures 39 and 43. The spanner 100 will therefore slip around the connector C.

[0160] As a result of this, it is not possible to use the spanner 100 to rotate the connector C in the wrong direction either by applying it or turning it in the wrong direction.

Claims

CLAIMS1 . A spanner for a connector, the spanner comprising a handle extending in a longitudinal direction and a head defining a substantially part circular cavity with an entrance in a closed configuration in which the width of the entrance is less than the maximum diameter of the cavity, the cavity having an entrance opposite to and facing away from the handle to receive a connector, the head comprising a pair of jaws which are biased together by a resilient member, such that when the spanner is moved longitudinally onto the connector, the jaws are separated against the action of the resilient member to allow the connector to enter the cavity, a thumb lever on one of the jaws, the thumb lever being positioned such that pressure on the thumb lever causes the jaws to move apart against the action of the resilient member from the closed configuration in which the width of the entrance is less than the maximum diameter of the cavity to an open configuration in which the jaws open out such that the width of the entrance is greater than the maximum diameter of the cavity in the closed configuration.

2. A spanner according to claim 1 , wherein one of the jaws is provided with teeth facing the cavity and the other is not.

3. A spanner according to claim 1 or claim 2, wherein the inner profiles of the jaws have a partially curved configuration which has the radius of curvature of the part circular cavity.

4. A spanner according to any preceding claim, wherein the inner profiles of the jaws have a curved inner profile, the curved inner profile extending for more than 180° of the circumference of the cavity, the angle at the centre of the cavity in the closed configuration being measured from one end of the curved inner profile to the other.

5. A spanner according to any preceding claim, wherein each of the jaws has a curved inner profile extending from the entrance of the cavity.

6. A spanner according to claim 1 , wherein the head is pivotally connected to the handle about a transverse axis which is parallel to the axis of rotation of the head, the headbeing biased in an operational position with respect to the handle by a spring loaded latch configured to release the head to pivot with respect to the handle about the transverse axis when the torque on the spanner exceeds a pre-determined threshold.

7. A combination of a spanner according to any one of the preceding claims and a connector, wherein the connector and spanner are dimensioned such that the spanner can be applied to and disconnected from the connector by depression of the thumb lever and movement of the spanner in the longitudinal direction.

8. A combination according to claim 7, wherein the connector has a substantially circular outer face in which a number of recesses are formed, wherein the inner profile of the cavity of the spanner follows the curvature of the substantially circular outer face and has teeth which are complementary with the recesses.

9. A combination of a spanner and a connector, the spanner comprising a handle extending in a longitudinal direction and a head defining a cavity, the head comprising a pair of jaws which are biased together by a resilient member to urge the jaws into a closed position surrounding a connector, at least one of the jaws having teeth which, in use, engage with complementary grooves in the connector, a first engagement feature on the head which is complementary with a second engagement feature on the connector, such that, when the spanner is placed onto the connector in a first orientation, the engagement features do not engage and prevent the jaws from fully closing, thereby preventing the teeth from entering the grooves, so that the spanner will slip around the connector, and when the spanner is placed onto the connector in a second orientation opposite to the first orientation, the engagement features engage to allow the jaws to fully close, so that the spanner can rotate the connector.

10. A combination according to claim 9, wherein: the first engagement feature comprises a pair of longitudinally spaced circumferential protrusions on the head, and the jaws extending longitudinally partially between the circumferential protrusions in a manner which is not symmetrical about a median plane between circumferential protrusions; and the second engagement feature comprises a pair of shoulders on the connector which engage with the circumferential protrusions to limit longitudinal movement of the spanner with respect to the connector, and grooves extending longitudinally partiallybetween the shoulders in a manner which is not symmetrical about a median plane between the shoulders and which is complementary to the jaws when the spanner is on the connector in the second orientation.

11. A combination according to claim 9 or 10, wherein the teeth have an asymmetric configuration such that they can only drivingly engage in the grooves in one rotational direction.12 A spanner for the combination according to claim 10, the spanner comprising a handle extending in a longitudinal direction and a head defining a cavity, the head comprising a pair of jaws which are biased together by a resilient member to urge the jaws into a closed position surrounding a connector, at least one of the jaws having teeth which, in use, engage with complementary grooves in the connector, and a first engagement feature in the form a pair of longitudinally spaced circumferential protrusions on the head, and the jaws extending longitudinally partially between the circumferential protrusions in a manner which is not symmetrical about a median plane between the circumferential protrusions.

13. A spanner according to claim 12, wherein one of the jaws is provided with teeth facing the cavity and the other is not.

14. A spanner according to claim 12 or claim 13, wherein the inner profiles of the jaws have a partially curved configuration which has the radius of curvature of the part circular cavity.

15. A spanner according to any of claims 12 to 14, wherein the inner profiles of the jaws have a curved inner profile, the curved inner profile extending for more than 180° of the circumference of the cavity, the angle at the centre of the cavity in the closed configuration being measured from one end of the curved inner profile to the other.

16. A spanner according to any of claims 12 to 15, wherein each of the jaws has a curved inner profile extending from the entrance of the cavity.

17. A spanner according to claim 12, wherein the head is pivotally connected to the handle about a transverse axis which is parallel to the axis of rotation of the head, the headbeing biased in an operational position with respect to the handle by a spring loaded latch configured to release the head to pivot with respect to the handle about the transverse axis when the torque on the spanner exceeds a pre-determined threshold.

18. A spanner comprising a handle extending in a longitudinal direction and a head defining a substantially part circular cavity with an entrance opposite to the handle to receive a connector, the head comprising a pair of jaws which are biased together by a resilient member, the jaws being relatively movable apart against the action of the resilient member from a closed configuration in which the width of entrance is less than the maximum diameter of the cavity in the closed configuration to an open configuration in which the jaws open out such that the width of the entrance is greater than the maximum diameter of the cavity in the closed configuration, the jaws having an inner profile which, when fitted to a connector with a complimentary outer profile is such that movement of the ratchet spanner in the longitudinal direction causes the jaws to move to the open position such that the spanner can be removed from the connector in the longitudinal direction.

19. A spanner according to claim 18, wherein the head is pivotally connected to the handle about a transverse axis which is parallel to the axis of rotation of the head, the head being biased in an operational position with respect to the handle by a spring loaded latch configured to release the head to pivot with respect to the handle about the transverse axis when the torque on the spanner exceeds a pre-determined threshold.

20. A spanner according to claim 19, wherein the head is free to pivot through an angle of at least 5° or about the transverse axis once the pre-determined torque threshold is exceeded.21 . A spanner according to claim 19, or claim 20, wherein the biasing force on the jaws is lower than the biasing force on the latch.

22. A spanner according to any of claims 18 to 21 , wherein at least one of the jaws is provided with ratchet teeth on its inner profile.

23. A spanner according to any claim 22, wherein both of the jaws are provided with ratchet teeth on their inner profiles.

24. A spanner according to any of claims 18 to 23, wherein the inner profiles of the jaws have a partially curved configuration which has the radius of curvature of the part circular cavity.

25. A spanner according to any of claims 18 to 24, wherein the inner profiles of the jaws have a curved inner profile, the curved inner profile extending for more than 180° of the circumference of the cavity, the angle the angle at the centre of the cavity in the closed configuration being measured from one end of the curved inner profile to the other.

26. A spanner according to any of claims 18 to 25, wherein each of the jaws has a curved inner profile extending from the entrance of the cavity.

27. A combination of a spanner according to any one of claims 18 to 26 and a connector, wherein the connector and spanner are dimensioned such that the spanner can be applied to and disconnected from the connector by movement of the spanner in the longitudinal direction.

28. A combination according to claim 27, wherein the connector has a substantially circular outer face in which a number of recesses are formed, wherein the inner profile of the cavity of the spanner follows the curvature of the substantially circular outer face and has teeth which are complementary with the recesses.

29. A method of removing the spanner according to any one of claims 18 to 26 from a connector, the method comprising applying a force to the spanner in a longitudinal direction away from the connector such that interaction between the spanner and the connector forces the jaws of the spanner apart to a sufficient extent that the spanner is removed from the connector by movement only in the longitudinal direction.

30. A method according to claim 29, wherein the connector has a substantially circular outer face in which a number of recesses are formed, wherein the inner profile of the cavity of the spanner follows the curvature of the substantially circular outer face and has teeth which are complementary with the recesses.31 . An open-ended ratchet spanner comprising a handle connected to a head, the head defining a socket having defining a cavity to receive a connector, a plurality of spring clips fixed into the wall of the socket facing the cavity, each spring clip mounted such that,in an unstressed state, one end of the spring clip protrudes at an angle into the cavity such that its end face can engage with a recessed feature on the connector to turn the connector when the spanner is rotated about an axis of rotation in the first direction, sufficient clearance being provided behind the end of the spring clip such that it can be resiliently displaced out of the cavity by rotation of the spanner about the axis of rotation in a second direction opposite to the first direction.

32. A spanner according to claim 31 , wherein the entrance to the cavity is narrower than the maximum diameter of the cavity.

33. A spanner according to claim 31 or claim 32, wherein each spring clip has a generally V shape configuration, with one arm having the one end protruding into the cavity and the other arm being embedded within the head to anchor the clip in place.

34. A spanner according to any of claims 31 to 33, wherein the handle and head are pivotally connected together to allow the angle of the head to be adjusted with respect to the handle about a pivot axis transverse to the axis of rotation.

35. A spanner according to claim 34, wherein a latch mechanism is provided between the handle and the head to selectively lock them in a number of different relative angular positions.

36. A spanner according to claim 35, wherein the latch mechanism comprises a spring loaded plunger on one of the handle or head configured to cause selective engagement with a plurality of teeth on the other of the handle or head which are arranged about the pivot axis such that the latch can selectively engage between different teeth to lock the handle and head in different angular configurations.

37. An adjustable wrench comprising two parts pivotally connected to each other, each part having a jaw on one side of the pivotal connection and a handle on the opposite side of the pivotal connection, one of the parts having a slot and the other having a pivoting element slidable along the slot to vary the position of the pivot axis; a variable stop between the handles, arranged such that a degree to which the handles can approach one another differs depending on the position of the pivot axis; wherein the inner face of each jaw is provided with at least one resilient element for engaging with an object to be gripped.

38. An adjustable wrench according to claim 37, wherein the resilient element is provided as a number of protuberances arranged around the inner face of each jaw.

39. An adjustable wrench according to claim 37 or claim 38, provided with a number of indicia which are selectively automatically displayed depending upon the position of the pivot axis.

40. An adjustable wrench according to any one of claims 37 to 39 wherein the variable stop is provided by a lug on one of the handles which projects towards the other handle and a series of steps of different heights on the adjacent handle, the lug being positioned such that it is selectively aligned with one of the steps depending upon the position of the pivot axis.

Images