EP2459349B1

EP2459349B1 - Multi-bit tool having spring loaded actuation mechanisms

Info

Publication number: EP2459349B1
Application number: EP10807826.2A
Authority: EP
Inventors: Fern Beauchamp
Original assignee: Individual
Current assignee: GRAND, GERARD
Priority date: 2009-07-31
Filing date: 2010-07-31
Publication date: 2017-03-15
Anticipated expiration: 2030-07-31
Also published as: WO2011017796A1; EP2459349A1; EP2459349A4

Description

FIELD OF THE INVENTION

The present invention relates to a multi-bit
apparatus having spring loaded actuation mechanisms, and more particularly to a multi-bit tool having spring loaded actuation mechanisms.

BACKGROUND OF THE INVENTION

Tools, such as multi-bit screwdrivers, that have a
plurality of tool bits that are selectively usable one at a time, are well-known. In use, one tool bit is manually selected at a time via a sliding button to extend forwardly out of a housing through a bit chuck to an extended in-use configuration. An actuation mechanism causes the selected tool bit to move to its extended in-use configuration in response to the sliding button moving forwardly, and causes the selected tool bit to move back to its retracted configuration in response to the sliding button moving rearwardly.
It is even known to make the actuation mechanism
automatic, through the inclusion of a spring arrangement, such that a small movement of an actuator button in a forward direction will cause the selected tool bit to move to its extended in-use position, and a small movement of that same actuator button it at rearward direction will cause the extended tool bit to return to its retracted position.
The problem with this prior art multi-bit screwdriver
is that a user must first retract the extended tool bit before extending another tool bit, which is a two-step process. Moreover, if the extended tool bit is not retracted before a second tool bit is extended, one or both of the actuator mechanisms of the extended or partially extended tool bits will jam.
It has been found that in one particular prior art
multi-bit driver having cartridge type spring loaded actuation mechanisms, namely United States Patent No. 7,275,466 issued October 2, 2007 to Cluthe , the cartridge type spring loaded actuation mechanisms are all closely fit into an outer housing so as to be in abutting relation. In use, it is common for the working elements of the cartridge mechanisms to become jammed during use. In fact, such jamming is so common, that the manufacturer/distributor of the product supplies instructions on the packaging for unjamming the actuation mechanisms, by tapping the bottom end of the screwdriver on a surface a few times to dislodge any stuck bits.
US Patent No. 2,071,510 discloses a selective magazine pencil having a number of lead holders rotatably mounted in a case, within tubes. Pressure springs act upon the lead holders.
Guide pins of the lead holders extend through slots in the tubes, which are aligned with slots in an inner sleeve. A tube length defines a cam face. The guide pins ride up the cam face when the inner sleeve is rotated. On reaching a drop edge of the cam face, a subsequent rotation can bring the lead holder into a position for writing, under the action of the spring.
It is an object of the present invention to provide a multi-bit tool having spring loaded actuation mechanisms.
It is another object of the present invention to provide a multi-bit tool having spring loaded actuation mechanisms, wherein the jamming of the tool bit assemblies and the spring loaded actuation mechanisms is significantly reduced, and perhaps almost eliminated.
It is a further object of the present invention to provide a multi-bit tool having spring loaded actuation mechanisms, which multi-bit tool is more ergonomic and therefore easier to use.

SUMMARY OF THE INVENTION

According to the present invention, there is provided an apparatus having a plurality of individually selectable working elements as claimed in claim 1.
Optional further features of the apparatus are defined in the dependent claims.
Other advantages, features and characteristics of the
present invention, as well as methods of operation and functions of the related elements of the structure, and the combination of parts and economies of manufacture, will become more apparent upon consideration of the following detailed description and the appended claims with reference to the accompanying drawings, the latter of which is briefly described herein below.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features which are believed to be
characteristic of the multi-bit tool according to the present invention, as to its structure, organization, use and method of operation, together with further objectives and advantages thereof, will be better understood from the following drawings in which a presently preferred embodiment of the invention will now be illustrated by way of example. It is expressly understood, however, that the drawings are for the purpose of illustration and description only, and are not intended as a definition of the limits of the invention. In the accompanying drawings:

Figure 1 is a perspective view from the front of the
preferred embodiment of the multi-bit tool according to the present invention, with the tool bit extended;
Figure 2 is a side elevational view of the preferred
embodiment of the multi-bit tool of Figure 1, with the tool bit extended;
Figure 3 is a side elevational view of the preferred
embodiment of the multi-bit tool of Figure 1, with the tool bit retracted;
Figure 4 is a front end elevational view of the
preferred embodiment of the multi-bit tool of Figure 1;
Figure 5 is a back end elevational view of the
preferred embodiment of the multi-bit tool of Figure 1;
Figure 6 is an exploded perspective view of the
preferred embodiment of the multi-bit tool of Figure 1;
Figure 7 is an exploded side elevational view of the
preferred embodiment of the multi-bit tool of Figure 1;
Figure 8 is an exploded perspective view of the
preferred embodiment of the multi-bit tool of Figure 1, with the front cone and a ridged collar not shown for the sake of clarity;
Figure 9 is a sectional side elevational view of the
preferred embodiment of the multi-bit tool of Figure 1, with the tool bit retracted;
Figure 10 is a sectional side elevational view of the
preferred embodiment of the multi-bit tool of Figure 1, with the tool bit extended;
Figure 11 is a perspective view of one of the
cartridges used in the preferred embodiment of the multi-bit tool of Figure 1, with the carriage member and the bit assembly in a retracted configuration;
Figure 12 is another perspective view of one of the
cartridges used in the preferred embodiment of the multi-bit tool of Figure 1, with the carriage member and the bit assembly in a retracted configuration;
Figure 13 is another perspective view of one of the
cartridges used in the preferred embodiment of the multi-bit tool of Figure 1, with the carriage member and the bit assembly in an extended in-use configuration;
Figure 14 is a perspective view of the substantially
annular housing used in the preferred embodiment of the multi-bit tool of Figure 1;
Figure 15 is a perspective view of the bit selector
used in the preferred embodiment of the multi-bit tool of Figure 1;
Figure 16 is a side elevational view of the used in the preferred embodiment of the multi-bit tool of Figure 1;
Figure 17 is a sectional side elevational view of the
used in the preferred embodiment of the multi-bit tool of Figure 1, taken along section line 17-17 of Figure 15;
Figure 18 is a sectional side elevational view of the
bit selector used in the preferred embodiment of the multi-bit tool of Figure 1, taken along section line 18-18 of Figure 15;
Figure 19 is a perspective view from the front of the
preferred embodiment of the multi-bit tool of Figure 1, with the outer housing, the front cap and the outer portion of the annular collar removed for the sake of clarity, and with the single lobe the extension cam surface on the annular collar about to move a first trigger member to its extension triggering position;
Figure 20 is a perspective view from the front
similar to Figure 19, but with the first trigger member almost at the top of the leading edge of the single lobe the extension cam surface and with the single lobe the extension cam surface on the annular collar about to move the first trigger member to its extension triggering position;
Figure 21 is a perspective view from the front
similar to Figure 20, but with the first trigger member at the top of the single lobe the extension cam surface and with the single lobe the extension cam surface on the annular collar having moved the first trigger member to its extension triggering position, and with the first working element in an extended in-use position;
Figure 22 is a perspective view from the front
similar to Figure 21, but with the first trigger member almost at the bottom of the trailing edge of the single lobe the extension cam surface and with the retraction cam surface on the annular collar having moved the first trigger member to its retraction triggering position, and with the first working element retracting from its extended in-use position to its retracted position;
Figure 23 is a perspective view from the front
similar to Figure 22, but with the first trigger member just past the bottom of the trailing edge of the single lobe the extension cam surface and with the first working element having retracted to its retracted position, and with the second trigger member on the leading edge of the single lobe the extension cam surface and with the single lobe the extension cam surface on the annular collar about to move the second trigger member to its extension triggering position;

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

Reference will now be made to Figures 1 through 23, which show a preferred embodiment of the multi-bit tool of the present invention, as indicated by general reference numeral 20. In brief, the preferred embodiment multi-bit tool 20 comprises a housing 30, a substantially rigid main frame member 40, spring loaded actuator mechanisms 60, a plurality of working elements 72 as part of bit assemblies 70, and a bit selector 90.
The preferred embodiment of the present invention is
an apparatus that in its preferred embodiment is in the form of a multi-bit tool 20 that comprises a substantially annular housing 30 having a central interior cavity 32 and a bit chuck 34 with a bit-receiving opening 36. The substantially annular housing 30 defines a central longitudinal axis 'L'. The housing 30 acts as the handle for the multi-bit tool 20, and may be of any suitable shape. As can be seen in the figures, the substantially annular housing 30 comprises a forward cone portion 38 and a central handle portion 39 secured one to the other in selectively separable relation by means of suitable threaded fasteners 31 for the sake of manufacturing convenience and to permit subsequent access to the central interior cavity 32 of the substantially annular housing 30.
The central handle portion 39 has a plurality of
radially arcuate plates 37p disposed at the front end thereof. In the preferred embodiment as illustrated, there are five arcuate plates 37p, with each arcuate plate 37p separated from the two adjacent arcuate plates 37p by a pin receiving slot 37s, the purpose of which will be discussed in greater detail subsequently.
The substantially annular housing 30 also has an end
cap 33 secured to the back end of the substantially annular housing 30 by means of suitable threaded fasteners 35 for the sake of manufacturing convenience and to permit subsequent access to the central interior cavity 32 of the substantially annular housing 30.
There is a substantially rigid main frame member 40
that has a front end 42 and a back end 44. In the preferred embodiment, as illustrated, the substantially annular housing 30 and the substantially rigid main frame member 40 are each separate and distinct pieces. The housing 30 and the substantially rigid main frame member 40 are structurally interconnected one to the other such that the substantially rigid main frame member 40 precludes significant torsional deformation of the housing 30.
The substantially rigid main frame member 40 is
retained within the interior cavity 32 of the housing 30 to be generally aligned along the longitudinal axis 'L'.
The substantially rigid main frame member 40 a
central core 46 with the plurality of actuator separators 43 extend radially outwardly from the central core 46, and also defines a plurality of longitudinal channels 41, as can readily be seen in the figures. The substantially rigid main frame member 40 is disposed within the housing 30 such that each of the plurality of longitudinal channels 41 is generally aligned along the longitudinal axis 'L'. The plurality of actuator separators 43 preferably extend radially outwardly from the longitudinal axis 'L'.
The central core 46 extends forwardly along the
longitudinal axis 'L' past the front of the proximal wall portions 48. Preferably, the central core 46 is tapered at its front end 47 to accommodate the passage of the tool bits 72 therepast.
Preferably, for the purpose of maximum rigidity and
minimum overall size and thickness, the substantially rigid main frame member 40 is made from metal or a suitable plastic. Any other suitable material or combination of materials could be used.
There is also a plurality of spring loaded actuator
mechanisms 60 operatively mounted within the interior cavity 32 of the housing 30, one spring loaded actuator mechanism 60 per trigger member 69, and vice versa. The plurality of spring loaded actuator mechanisms 60 are carried in rigidly retained relation by the substantially rigid main frame member 40 within the interior cavity 32 of said housing 30. Each spring loaded actuator mechanism 60 is mounted in rigidly retained relation within one channel 41 of the substantially rigid main frame member 40. The plurality of spring loaded actuator mechanisms 60 are mounted within the substantially rigid main frame member 40 such that contact of each spring loaded actuator mechanism 60 with the other spring loaded actuator mechanisms 60 is precluded.
Preferably, but not necessarily, the spring loaded
actuator mechanisms 60 comprise sub-assemblies containing one or more springs and other components and the like. Alternatively, the spring loaded actuator mechanisms comprise assembled individual components within the housing 30 and supported by the housing 30 and/or the substantially rigid main frame member 40.
Cartridge type spring loaded actuator mechanisms 60
are well known and can be found in various prior art patent documents such as United States Patent No. 2,854,745 , the teachings of which are incorporated herein by reference.
Each spring loaded actuation mechanism 60 has an
element extending configuration and an element retracting configuration. In the element extending configuration, the working element 72 is caused to move to the extended in-use position. In the element retracting configuration, the working element 72 is caused to move to the retracted position. In the preferred embodiment, the working element 72 is part of a bit assembly 70 and specifically comprises a tool bit 72.
Each spring loaded actuator mechanism 60 has a
carriage member 66 that is movable between a rearward position, as indicated by arrow 'A' in Figure 9, and a forward position, as indicated by arrow 'B' in Figure 10, and a trigger member 69 that is slidably movable between an extension triggering position, as is indicated by arrow 'C' in Figure 9, and a retraction triggering position, as is indicated by arrow 'D' in Figure 9. The spring loaded actuation mechanism 60 is urged to its retracting configuration and the carriage member 66 is moved to its rearward position by movement of the trigger member 69 to its retraction triggering position, similarly, the spring loaded actuation mechanism 60 is urged to its extended in-use configuration and the carriage member 66 is moved to its forward position by movement of the trigger member 69 to its extension triggering position.
Each trigger member 69 comprises a cam follower 69f
that engages a cooperating cam surface 93 on the annular collar member 90. Further, each trigger member 69 is mounted for longitudinal sliding movement over a short distance, within the associated spring loaded actuator mechanism 60.
In the preferred embodiment, as illustrated, the cam
follower 69f comprises a raised cam follower 69f projecting outwardly from a base portion 69g. The raised cam follower 69f has a height of about 2 millimeters (mm) in order to not protrude too far, as it must be readily accommodated within the ridged outer ring 90a. The cam followers 69f are engaged by an extension portion 92 on the bit selector 90, as will be discussed in greater detail subsequently.
As can be best seen in Figures 11 through 13, the
spring loaded actuator mechanisms 60 are substantially straight along their length. Each spring loaded actuator mechanism 60 has an elongate substantially straight slot 62 therein. As the carriage member 66 travels along its spring loaded actuator mechanism 60, a portion of the carriage member 66 rides along the elongate slot 62 in the spring loaded actuator mechanism 60.
The multi-bit tool 20 also comprises a plurality of
working elements 72 operatively mounted within the housing 30. In the preferred embodiment, as illustrated, each working element comprises a tool bit, but alternatively could comprise other suitable types of working elements, such as parts of a toy, and so on. Each bit assembly 70 has a tool bit 72 at a front end and is operatively mounted within the housing 30 for movement by the actuator mechanism 60 between a retracted position corresponding to the retracted configuration of the actuator mechanism 60 and the rearward position of the carriage member 66, and a forwardly extended in-use position corresponding to the forwardly extended in-use configuration of the actuator mechanism 60 and the forward position of the carriage member 66. In the forwardly extended in-use configuration, the tool bit 72 extends outwardly from the housing 30 through the opening 36 of the bit chuck 34.
Preferably, each tool bit 72 is substantially
cylindrically shaped, in order to accommodate the passage of bits 72 past the tapered front end 47 of the central core 46.
Each bit assembly 70 is operatively connected to the
carriage member 66 on a corresponding spring loaded mechanism 80 for cooperative movement therewith. In use, as each carriage member 66 moves between its rearward position and its forward position, the corresponding spring loaded actuator mechanism 60 is retained substantially in its correct form by the substantially rigid main frame member 40.
The multi bit tool 20 further comprises the bit
selector 90 having an extension portion 92 for engaging each trigger member. In the preferred embodiment, as illustrated, the bit selector 90 is in the form of an annular collar mounted on the housing 30 for manual rotation about the longitudinal axis 'L'. The bit selector 90 is thereby mounted on the housing 30 for movement through an actuation position for each actuation mechanism 60.
The annular collar 90 comprises an annular ring shaped
main body that comprises a ridged outer ring 90a is secured to the internal cam ring 90b for co-rotation around the housing 30, about the longitudinal axis 'L'. The internal cam ring 90b fits over the five arcuate plates 37p in reasonably close fitting but freely rotatable relation.
As can be best seen in Figures 15 through 17, the
extension portion 92 comprises an extension cam surface 93 disposed on the annular collar 90. The extension cam surface 93 has a single lobe 91 for causing the trigger members 69 to move to their respective extension triggering positions. The single lobe 91 has a leading surface 93a and a trailing surface 93b adjoined by a peak 93c. The leading surface 93a of the single lobe 91 has a slope of about forty five (45) degrees. The angle of forty five (45) degrees has been found to be suitable for moving the trigger members 69 more than a required threshold distance of about twelve (12) millimeters along the longitudinal axis 'L' while still fitting in five bit assemblies 70 and actuation mechanisms 60 within the main body 30 around the longitudinal axis 'L'.
It has also been found that if the peak 93c of the
single lobe 91 is curved and has a radius of about five (5) millimeters, the cam followers 69f can readily follow the peak 93c of the single lobe 91.
In each actuation position, the extension portion 92
of the bit selector 90 engages a corresponding trigger member 69, thereby moving the trigger member 69 to the extension triggering position, thus urging the corresponding spring loaded actuation mechanism 60 to the element extending configuration, thereby moving the corresponding working element 72 from its retracted position to its extended in use position.
The bit selector 90 further comprises a retraction
portion 94. As can be seen in Figures 15 through 18, the retraction portion 94 is disposed at the same general longitudinal area of the bit selector 90 as is the single lobe 91, and extends much of the way around the diameter of the bits selector 90. The retraction portion 94 engages the trigger member 69 of the spring loaded actuation mechanism 60 that has its tool bit 72 in its extended in-use position. Such engagement of the trigger member 69 by the retraction portion 94 of the bit selector 90 occurs when the bit selector 90 is moved from a neutral position to a retraction position. Further, the trigger member 69 is thereby moved to the retraction triggering position, thus urging the spring loaded actuation mechanism corresponding to the working element 72 that is in its extended position to the element retracting configuration. The retraction portion 94 of the bit selector 90 thereby moves the corresponding working element 72 in its extended in use position moved to its retracted position.
In the preferred embodiment, a neutral position might
be anywhere between the retraction positions, and in that case would include the extension triggering positions. It is also contemplated that alternatively the neutral positions might be elsewhere, including positions that are longitudinally displaced from the presently shown protraction positions. In the preferred embodiment, as illustrated, there is a plurality of neutral positions, with a neutral position being disposed between each one of the actuation positions. Accordingly, the movement of the bit selector from the neutral position to the retraction position comprises the movement of the bit selector between a plurality of actuation positions. The retraction portion engages the trigger members between the actuation positions.
As can be seen in Figures 15 through 18, the
retraction portion 94 actually engages the trigger member 69 of the spring loaded actuation mechanism 60 that has its working element 72 in an extended in-use position, when the bit selector 90 is moved from the neutral position to the retraction position. Further, the retraction portion 94 causes any working element 72 not in its retracted position to be moved to its retracted position before another working element 72 is moved to its extended in use position.
As can be best seen in Figures 15 through 18, the
retraction portion 94 comprises a retraction cam surface 95 disposed on the annular collar 90. The extension cam surface 93 and the retraction cam surface 95 face each other with a cam follower receiving gap 96 in between. The extension cam surface 93 and the retraction cam surface 95 are spaced apart along the longitudinal axis 'L' by a distance slightly greater than the width of the cam follower 69f
As can also be seen in Figures 15 through 18, a
portion of the cam follower receiving gap 96 is open to the exterior of the annular collar 90 and a portion of the cam follower receiving gap 96 is closed off to the exterior of the annular collar 90 by an outer wall portion 97. The reason for this is for ease of manufacturing. Further, the extension cam surface 93 and the retraction cam surface 95 extend fully around the periphery of the annular collar 90. Accordingly, the bit selector 90 can be turned continuously about the longitudinal axis 'L' to contact and move the trigger members 69 to their respective extension triggering positions and retraction triggering positions.
Reference will now be made to Figures 19 through 23, which show the multi-bit tool 20 according to the present invention in use. As shown in Figure 19, all of the working elements 72 have been retracted to their respective retracted positions. Only three working elements are shown for the sake of clarity, namely a first working element 72a, a second working element 72b, and a third working element 72c. The first trigger member 69a is about to be engaged by the leading surface 93a of the extension cam surface 93 on the single lobe 91 as the annular collar 90 is rotated in the direction of arrow 'E'. As can be seen in Figure 20, the annular collar 90 has been continued to rotate in the direction as shown by arrow 'F' and the first trigger member 69a has moved up the leading surface 93a of the extension cam surface 93 of the single lobe 91 and is nearly at the peak 93c. The first trigger member 69a has just reached the threshold position of the first actuator mechanism 60a and accordingly the first actuator member 60a is about to move the corresponding first working element 72a to its extended in-use position.
Reference will now be made to Figure 21, which shows
the first trigger member 69a having reached the peak 93c of the extension cam surface 93, as caused by continued rotation of the annular collar 90 in the direction of arrow 'G'. Also shown is the first tool bit 72 of the first working element 72a in its extended in-use position.
Reference will now be made to Figure 22, which shows
the annular collar 90 having continued to rotate in a direction as indicated by arrow 'H', to thereby move the first trigger member 69a moving towards the bottom of the trailing surface 93b of the extension cam surface 93 on the single lobe 91, as moved there by the leading edge 95a of the retraction cam surface 95. The first working element 72a is thereby being retracted from its extended in-use position to its retracted position. The second trigger member 69b is being pushed up the leading edge 93a of the extension cam surface 93. Continued travel of the second trigger member 69b along the leading edge 93a of the extension cam surface 93 will shortly cause the second trigger member 69b to reach the threshold for triggering the second actuation mechanism 60b, at which point the second working element 72b will be moved from its retracted position to its extended in-use position.
Reference will now be made to Figure 23, that shows
the annular collar 90 having been turned slightly more in the direction of arrow 'I', and the second trigger member 69b having travelled up the leading edge 93a of the extension cam surface 93a slight bit more, just to the threshold distance for triggering corresponding second actuation mechanism 60b. Correspondingly, the second working element 72b has started to move forwardly from its retracted position to its extended in-use position.
In another aspect of the present invention, it is contemplated that in one the embodiment of the present invention, the present invention comprises a multi-implement apparatus that could be a toy that functions in an analogous manner to the multi-bit tool 20 as described.
As can be understood the accompanying drawings, the present invention provides a multi-bit tool having spring loaded actuation mechanisms, wherein the jamming of the tool bit assemblies and the spring loaded actuation mechanisms is significantly reduced, and perhaps almost eliminated, and which multi-bit tool is more ergonomic and therefore easier to use than prior art multi-bit tools, all of which features are unknown in the prior art.
In an alternative embodiment of the present invention, it is contemplated that trigger members 69 might be individually selectable for either extension or retraction of the working elements 72. For instance, the bit selector 90 might be used to cause extension of the working elements 72, but other means might be used to cause the retraction of the element 72.
Further, in another alternative embodiment, it is contemplated that the working element 72 could be pens, parts of a toy, lipstick, and many other types of elements, and accordingly, the apparatus according to the present invention might be a tool, a toy, and so on

Claims

An apparatus (20) having a plurality of individually selectable working elements (72), said apparatus comprising:
a housing (30) having a bit chuck (34) with a bit-receiving opening (36) and defining a longitudinal axis (L);

a plurality of working elements (72) operatively mounted within said housing (30) and each working element being independently movable between a retracted position and an extended in-use position;

a plurality of spring loaded actuation mechanisms (60) operatively mounted within said housing (30), one actuation mechanism for each working element (72);

wherein each spring loaded actuation mechanism (60) has an element extending configuration whereat said working element (72) is caused to move to said extended in-use position and an element retracting configuration whereat said working element (72) is caused to move to said retracted position;

characterized in that each spring loaded actuation mechanism (60) has a trigger member (69) movable between an extension triggering position and a retraction triggering position, and wherein said spring loaded actuation mechanism (60) is urged to its retracting configuration by movement of said trigger member (69) to its retraction triggering position and said spring loaded actuation mechanism (60) is urged to its extended in-use configuration by movement of said trigger member (69) to its extension triggering position; and,

a bit selector (90) having an extension portion (92) for engaging each trigger member (69), and mounted on said housing (30) for movement through an actuation position for each actuation mechanism (60);

wherein in each actuation position, said extension portion (92) of said bit selector (90) engages a corresponding trigger member (69), thereby moving said trigger member to said extension triggering position, thus urging the corresponding spring loaded actuation mechanism (60) to said element extending configuration, thereby moving the corresponding working element (72) from its retracted position to its extended in-use position.
The apparatus of claim 1, wherein said bit selector comprises an annular collar (90) mounted on said housing for manual rotation about said longitudinal axis.
The apparatus of claim 2, wherein said annular collar comprises an annular ring-shaped main body (90a, b).
The apparatus of claim 3, wherein said trigger member comprises a cam follower (69f) on a base portion (69g).
The apparatus of claim 4, wherein said cam follower comprises a raised cam follower projecting outwardly from said base portion.
The apparatus of claim 4, wherein said extension portion comprises an extension cam surface (93) disposed on said annular collar.
The apparatus of claim 6, wherein said bit selector further comprises a retraction portion (94) that engages the trigger member of the spring loaded actuation mechanism having its working element in its extended in use position, when said bit selector is moved from a neutral position to a retraction position, thereby moving said trigger member to said retraction triggering position, thus urging the spring loaded actuation mechanism corresponding to the working element in its extended position to said element retracting configuration, thereby moving the working element in its extended in-use position to its retracted position.
The apparatus of claim 7, wherein said retraction portion engages the trigger member of each spring loaded actuation mechanism, when said bit selector is moved from said neutral position to said retraction position, thereby causing any working element not in its retracted position to be moved to its retracted position before another working element is moved to its extended in-use position.
The apparatus of claim 8, wherein the movement of said bit selector from said neutral position to said retraction position comprises said movement of said bit selector between a plurality of actuation positions.
The apparatus of claim 9, wherein said retraction portion engages said trigger members between said actuation positions.
The apparatus of claim 8, wherein said retraction portion comprises a retraction cam surface (95) disposed on said annular collar.
The apparatus of claim 8, wherein said extension cam surface and said retraction cam surface face each other with a cam-follower-receiving gap (96) in between.
The apparatus of claim 12, wherein a portion of said cam-follower-receiving gap is open to the exterior of said annular collar and a portion of said cam-follower-receiving gap is closed off to the exterior of said annular collar by an outer wall portion (97).
The apparatus of claim 13, wherein said extension cam surface has a single lobe (91) for causing said trigger members to move to their respective extension triggering positions.