AU2013101584A4 - Improvements to multi-bit tools - Google Patents

Abstract

A multi-bit tool including: a housing incorporating at least two tool bit storage recesses, a bore and a drive socket portion axially aligned with the bore; a sleeve rotatably located in the bore of the housing, the sleeve including a flange portion and a slot portion; a bolt slidably located in the sleeve between a bit loading position and a working position. The bolt has a claw, a flange portion and a drive input portion, the claw providing axial location of the tool bit relative to the bolt, the flange portion providing rotational location of the bolt relative to the housing, the drive input portion of the bolt receiving drive input to the tool, the flange portion of the bolt driving the housing to thereby transmit the drive input to the drive socket portion of the housing. The housing and the sleeve can each include at least one sleeve rotation control feature, the two sleeve rotation control features being mated when a tool bit is selected to lock rotation of the sleeve relative to the housing and the two features being disengaged when a bit is unloaded to permit relative rotation between the sleeve and the housing. 1 21 24 5 3 12 g Figure 1 Figure 2

Description

1 IMPROVEMENTS TO MULTI-BIT TOOLS TECHNICAL FIELD [0001] This invention relates to the field of multi-bit tools and more specifically to improvements in the operation of the selection mechanism. BACKGROUND [0002] A multi-bit tool is disclosed in the applicant's earlier International Patent Application No. PCT/AU2011/000026, details of which are incorporated herein by reference. The multi-bit tool includes a housing incorporating multiple storage recesses for tool bits and a sleeve and bolt assembly operable between a bit loading position and a working position. [0003] The present invention was developed with a view to providing improvements in the operation and use of multi-bit tools. SUMMARY OF INVENTION [0004] The present invention provides a multi-bit tool including: a housing incorporating at least two recesses, a bore and a drive socket portion axially aligned with the bore, each recess providing a storage location for a tool bit; a sleeve rotatably located in the bore of the housing, the sleeve including a flange portion and a slot portion, the sleeve having a major axis; a bolt slidably located in the sleeve between a bit loading position and a working position, the bolt having a claw, a flange portion and a drive input portion, the claw being provided to accommodate a drive end of a tool bit and provide axial location of the tool bit relative to the bolt, the drive input portion of the bolt receiving drive input to the tool, the flange portion of the bolt driving the housing to thereby transmit the drive input to the drive socket portion of the housing. [0005] The flange portion of the bolt may include at least one eccentric protrusion extending radially from the flange to engage with the end of one of said at least two recesses to provide rotational location of the bolt relative to the housing in the 2 working position. [0006] In one or more forms of the present invention the housing may include at least one sleeve rotation control feature and the sleeve may include at least one sleeve rotation control feature, the two features being mated when a tool bit is selected to lock rotation of the sleeve relative to the housing and the two features being disengaging when a bit is unloaded to permit relative rotation between the sleeve and the housing. [0007] Alternatively, the multi-bit tool may include: a sleeve rotation control feature (such as a groove or radial hole on the inside of the housing adjacent the flange portion of the sleeve when assembled) provided in the housing for each recess, and a drop-in locking device (such as a pin, ball or roller) provided in a sleeve rotation control hole (such as a radial bore or slot) in the sleeve. In this case, the drop-in locking device partially displaces into a sleeve rotation control feature when a tool bit is selected, to thereby lock rotation of the sleeve relative to the housing, and the drop-in locking device disengages out of the sleeve rotation control feature when a bit is unloaded to thereby permit relative rotation between the sleeve and the housing. [0008] The sleeve rotation control hole in the sleeve may have or include an inner hole at its inner end, the inner hole uncovering part of an outer surface of the bolt, the bolt may include a sleeve rotation release recess on the outer surface of the bolt that is aligned with the hole at the inner end of the sleeve rotation control hole when the bolt is fully withdrawn (in the bit loading position), and a sleeve rotation lock actuating ball may be provided in the inner end of the sleeve rotation control hole. Ideally, the dimensions of the drop-in locking device and the sleeve rotation lock actuating ball are such that: when the bolt is not fully withdrawn and the sleeve rotation lock actuating ball is not engaging into the sleeve rotation release recess (instead riding on the outer surface of the main portion of the bolt) the drop in locking device is prevented from displacing entirely into the sleeve rotation control hole in the sleeve and therefore remains partially in a said sleeve rotation control feature in the housing, thereby preventing rotation of the sleeve relative to 3 the housing unless the bolt is fully withdrawn; and when the bolt is fully withdrawn and the sleeve rotation lock actuating ball is engaging into the sleeve rotation release recess, if the sleeve rotation control hole in the sleeve is not aligned with a said sleeve rotation control feature then the bolt is locked in the fully withdrawn position. A sleeve rotation detent spring may be provided in the sleeve rotation control hole, said spring having a free length such that less than half of the drop-in locking device is urged into any sleeve rotation control feature in the housing aligned with the sleeve rotation control hole in the sleeve to thereby provide a detent function (as opposed to a locking function). Preferably, the sleeve rotation lock actuation ball is able to pass inside or through said spring towards the drop-in locking device when the bolt is not fully withdrawn and the sleeve rotation lock actuating ball is not engaging into the sleeve rotation release recess. Alternatively, the sleeve rotation lock actuation ball may have a larger outer diameter than the spring diameter, thus being sprung loaded to perform a detent only function. In this case the sleeve rotationa lock function may be provided by a separate drop-in pin. [0009] Alternatively, the drop-in locking device may be a locking pin and the sleeve rotation control hole may be a locking pin hole in the sleeve, and the sleeve rotation control feature may be a locking pin hole in the housing for each of said at least two tool storage recesses, the locking pin dropping partially into one of the locking pin holes in the housing when a bit is selected to prevent rotation of the sleeve relative to the housing, the locking pin dropping out of the hole in the housing when a bit is unloaded to permit relative rotation between the sleeve and the housing. [0010] The locking pin may include a first end which drops into the hole in the housing and a second end which has a rounded feature (such as a part of a sphere, or a "dome top"), and the bolt may include a recess to mate with the rounded feature of the locking pin when the bolt is in the bit loading position. For example, the length of the locking pin can be such that the locking pin is engaged with the housing unless the rounded feature is mated into the associated recess 4 on the bolt. This ensures that the bolt and sleeve assembly can only be rotated inside the housing when the bolt is fully withdrawn in the bit-loading position. [0011] The housing may include a sleeve rotation detent feature (such as a hole or groove) for each recess and the sleeve may include a radial hole locating a sleeve rotation detent ball and a sleeve rotation detent spring. The sleeve rotation detent feature for each recess in the housing may be the sleeve rotation control feature (i.e. they are common, as only one at a time is used for detent functionality and one at a time for locking pin functionality). [0012] In one or more forms of the present invention the multi-bit tool may include a single direction (non-reversing) device to limit or prevent rotation of the sleeve relative to the housing. This can allow the operation of the tool to be optimised for rotation of the selection mechanism including the sleeve in a single direction. For example, the single direction device may include a roller pin located in a tapering recess in the housing or in the sleeve. As the sleeve is rotated in a first direction relative to the housing the roller pin is rolled along the tapering recess until it no longer firmly or driveably engages both housing and sleeve, so the sleeve is free to rotate within the housing. As the sleeve is rotated in an opposite direction to the first direction, the roller pin is rolled along the tapering recess which engages the rolling pin increasingly firmly between the housing and the sleeve limiting rotation of the sleeve within the housing. [0013] Where the multi-bit tool includes both a locking pin and a single direction device, each said locking pin hole may include a guide slot. The depth of the guide slot may be greatest near the intersection of the guide slot with its associated locking pin hole. The guide slot allows the locking pin to start to move radially prior to becoming aligned with the locking pin hole to prevent overshoot (where the locking pin is rotated past the locking pin hole without engaging in the locking pin hole, which can require the sleeve to be rotated 360 degrees before the locking pin can engage as required). The guide slots are one feature that can be optimised if reversing rotation of the selection mechanism is limited or prevented.

5 [0014] One or more forms of the present invention may provide an (or at least one) aligning pin inserted or integrated into the housing, said aligning pin(s) extending from an inner surface of the housing adjacent an outer end surface of the flange of the sleeve in use. In that case, an alignment slot for each recess (ie there need to be as many alignment slots as there are useful rotational positions of the sleeve) may be provided in the outer end surface of the flange of the sleeve, such that as the bolt is drawn back, the sleeve translates (a small distance) axially with the bolt until the aligning pin is engaging with one of said alignment slots. Similarly, alignment slots may be provided on a surface of the flange of the bolt to clear or engage with the aligning pin(s) in the housing when the bolt is in a working position. [0015] It will be convenient to further describe the invention by reference to the accompanying drawings which illustrate preferred aspects of the invention. Other embodiments of the invention are possible and consequently the provision of the accompanying drawings and the following description thereof should not be taken to limit the scope of the above description of the invention. BRIEF DESCRIPTION OF DRAWINGS [0016] In the drawings: [0017] Figure 1 is a detailed cross-sectional view through a housing, sleeve and bolt of a possible embodiment of the present invention. [0018] Figure 2 is a partially sectioned perspective view of a multi-bit tool according to a possible embodiment of the present invention. [0019] Figure 3 is an exploded and partial section view of a sleeve and bolt of a possible embodiment of the present invention. [0020] Figure 4 is a detailed cross-sectional view through a housing, sleeve and bolt of a possible embodiment of the present invention showing detent operation. [0021] Figure 5 is a detailed cross-sectional view similar to Figure 4 but showing 6 locking operation. [0022] Figure 6 is a perspective view of a sleeve of the present invention, sectioned through the flange. [0023] Figure 7 is a perspective view of a sleeve of the present invention, sectioned through the flange as Figure 6, but showing an alternative arrangement. [0024] Figure 8 is a perspective view of a housing according to a possible embodiment of the present invention. [0025] Figure 9 is a perspective view of a sleeve according to a possible embodiment of the present invention. [0026] Figure 10 is a perspective view of a bolt according to a possible embodiment of the present invention. DESCRIPTION OF PREFERRED EMBODIMENT [0027] Referring initially to Figure 1 there is shown a section through an assembled multi-bit tool 1 of the type disclosed in the Applicant's International Application Number PCT/AU2011/000026, details of which are incorporated herein by reference. The multi-bit tool 1 has three major components, a housing 2, a sleeve 3 inserted into the housing 2, and a bolt 4 sliding inside the sleeve 3. [0028] Figure 2 shows a partial section of the housing 2 which includes three storage recesses or chambers 5 to hold tool bits ready for selection. The end portion has been sectioned to reveal features such as the face 6 against which the flange of the sleeve sits (the sleeve being able to rotate about the major axis of the housing). [0029] Figure 3 shows an exploded view of the bolt 4 and sleeve 3. The flange 7 of the bolt 4 is partially cut away and the flange 8 of the sleeve 3 is also sectioned (in the same plane as the section of Figure 1) to show the bolt slide and sleeve rotation features. The bolt slide pin 9 is assembled into the radial hole 10 in the 7 sleeve and protrudes into the bolt slide groove 11 to guide or control the rotation of the bolt relative to the sleeve as the bolt is withdrawn. The bolt slide detent spring 12, cap 13 and bolt slide detent ball 14 are loaded into the radial hole 15 in the sleeve so the ball 14 is spring-loaded into the bolt slide detent depressions 16 in the working and bit-loading positions. The sleeve rotation detent spring 17, cap 18 and sleeve rotation detent ball 19 are loaded into the radial hole 20 in the sleeve, so the ball 19 is spring-loaded into the sleeve rotation control holes 21 in the housing 2 (shown in Figures 1 and 2). The drop-in locking pin 22 is loaded into the radial hole 23 and has a rounded feature 24 (or dome top) which mates with a sleeve rotation release recess or depression 25 in the bolt when the bolt is withdrawn fully into the bit loading position. The opposite end of the drop-in locking pin 22 is usually engaged into one of the sleeve rotation control holes 21 in the housing, locking rotation of the sleeve. Only when the bolt is fully withdrawn is the sleeve rotation release depression 25 aligned with the drop-in locking pin to allow the rounded feature 24 to mate into the depression 25 so the drop-in locking pin is no longer engaged in one of the sleeve rotation control holes 21 in the housing. This ensures that the sleeve and bolt assembly can only be rotated in the housing when the bolt is fully withdrawn into the bit loading position and that the bolt cannot be returned until it is fully aligned with a tool bit storage recess or chamber 5. [0030] There is a channel 28 cut into the sleeve to permit tool bits to pass between the claw 29 of the bolt 4 and the storage chambers when the bolt is fully retracted in the bit loading position. [0031] A roller pin 26 is also shown (in Figures 1 and 3) in a groove or slot 27 of varying depth which together provide a single direction device similar to the function of a ratchet. The depth of the slot 27 reduces or tapers as the slot sweeps around the sleeve such that when assembled, at one end the roller pin can slide past the housing allowing the sleeve to rotate relative to the housing. When the sleeve is rotated in the opposite direction relative to the housing, the roller pin is dragged towards the narrower end of the slot where the roller pin 8 becomes pinched between the sleeve and the housing, limiting rotation of the sleeve relative to the housing in this opposite direction. This provides a single direction function for the rotation of the sleeve relative to the housing which can allow other parts of the tool to be optimised for action in this single direction. [0032] One such example of the tool action being optimised for single direction operation is shown in Figure 2, in which the partial cut-away section of the housing also reveals one of the sleeve rotation control holes 21 and a guide slot 32. The guide slot allows the drop-in locking pin 22 to start to fall into the sleeve rotation control hole 21 before the drop-in locking pin is aligned with the sleeve rotation control hole. This ensures that the drop-in locking pin engages into the sleeve rotation control hole more readily as the sleeve is rotated past the suitable position in the housing, allowing the tool to be operated faster. The grooves 33 in the outer of the housing 2 locate a retaining ring (not shown). [0033] In Figures 4 and 5 the functions of the drop-in locking pin and the sleeve rotation detent have been combined. The bolt slide pin 9 and the bolt slide detent arrangement is similar to that shown in Figures 1 and 3, like components using the same reference numerals. Additional bores or through-drillings that may be present for ease of manufacture are omitted in Figures 4 and 5 to improve clarity. [0034] In Figure 4 the sleeve rotation detent ball 19 is shown partially engaging into a sleeve rotation control groove 41 instead of into the sleeve rotation control holes shown in Figures 1 and 2. As with the sleeve rotation control holes there is a sleeve rotation control groove for each storage recess, so in this example, there are three. [0035] The sleeve rotation detent spring 17 is close to or at its free length (i.e. fully extended) in Figure 4 at which length it pushes the sleeve rotation detent ball 19 into the sleeve rotation control groove 41 sufficiently to provide a detent function but not lock rotation of the sleeve relative to the housing. As the sleeve rotation control groove is wide enough and deep enough for the sleeve rotation detent ball 19 to enter further, so when the radial hole 20 is facing downwards the ball can fall 9 into and stay in a groove below centre as shown in Figure 5. This provides the same function as the drop-in pin 22, so as with the radial hole for the drop-in pin in Figures 1 and 3, the radial hole 20 for the sleeve rotation detent ball 19 is preferably located opposite the channel 28 in the sleeve. As the sleeve is being rotated between storage recess positions (i.e. while the sleeve rotation detent ball 19 is not aligned with one of the sleeve rotation control grooves 41) , the sleeve rotation detent spring is compressed. When the sleeve rotation detent ball is aligned with whichever sleeve rotation control groove that is below it, the spring can extend to its free length again, this spring extension action helping to urge or fire the ball 19 into the groove 41 which minimises or negates the benefit of the single direction of rotation of the sleeve from Figures 1 to 3 and of the guide slot 31 shown in Figure 2. When engaging with the lower sleeve rotation control groove 41 the sleeve rotation detent ball 19 has a function similar to that of the drop-in locking pin 22 of Figures 1 to 3. [0036] The smaller sleeve rotation lock actuating ball 42 shown in Figures 4 and 5 performs a similar function to the rounded feature or dome top 24 on the drop-in pin in Figures 1 and 3. That is, only when the bolt is fully withdrawn into the bit loading position can the sleeve rotation lock actuating ball 42 engage into the sleeve rotation release recess 25 leaving clearance as shown in Figure 4 for the sleeve rotation detent ball 19 to move towards the bolt and compress the sleeve rotation detent spring 17. At all other times the sleeve rotation lock actuating ball 42 rides on the outer of the main cylindrical portion of the bolt 4 (in which position it is sitting more inside the sleeve rotation detent spring 17, if not always as far as when the radial hole 20 for the sleeve rotation detent is facing downwards as shown in Figure 5) preventing the sleeve rotation detent ball 19 from disengaging out of whichever sleeve rotational control groove that it is seated. The sleeve rotation lock actuating ball 42 thereby prevents rotation of the sleeve and bolt assembly relative to the housing unless the bolt is fully withdrawn into the bit loading position. [0037] Also, moving the bolt out of the fully withdrawn position requires the sleeve 10 rotation lock actuating ball 42 to be able to ride up out of the sleeve rotation release recess 25 and then run along the outside of the main cylindrical portion of the bolt, so the sleeve rotation lock actuating ball 42 also acts as a bolt return lock preventing the bolt from being returned to the working position unless the sleeve is aligned with a storage recess. That is, while the sleeve rotation detent ball 19 is not aligned with one of the sleeve rotation control grooves 41, the ball 19 prevents the sleeve rotation lock actuating ball 42 from disengaging out of the sleeve rotation release recess 25, which in turn keeps the bolt 4 in the fully withdrawn bit loading position. [0038] Figure 6 shows a sleeve 3 suitable for use in the arrangement described for Figures 4 and 5 above, and is again sectioned through the sleeve flange 8 showing the additional bores or drilling often present for ease of part production or assembly. The sleeve rotation detent ball 19 and the smaller sleeve rotation lock actuating ball 42 are also shown with the sleeve rotation detent spring omitted for clarity. [0039] Figure 7 shows an alternative arrangement equivalent to the parts in Figure 6. The sleeve rotation detent ball 19 has been replaced with a sleeve rotation detent roller 43 and the radial hole in the sleeve 20 for receiving the sleeve rotation detent ball has been adapted with a groove 44 to locate the roller whilst still allowing it to translate radially relative to the sleeve 3. As with the radial hole or bore 20, the groove 44 for the sleeve rotation detent roller 43 is preferably opposite the channel 28 in the sleeve. [0040] Figure 8 shows an aligning pin 51 protruding inwards from the housing 2 and Figure 9 shows a sleeve 3 having alignment slots 52 formed in the outer end surface of the flange 8. As the bolt is drawn back towards the bit loading position, the sleeve 3 is drawn back to seat one of the alignment slots 52 on to the aligning pin 51. The engagement of the aligning pin into an aligning slot reacts any torsional forces between the housing and the sleeve as the bolt slide pin follows the curved or angled end portion of the bolt slide groove to twist the bolt into the bit loading orientation relative to the sleeve. This helps maintain the correct 11 alignment between the housing and the sleeve as the bolt is withdrawn and approaching the bit loading position, ensuring the free operation of the drop-in pin from Figures 1 and 3 or the equivalent operation of the sleeve rotation detent ball or roller from Figures 4 to 6 or Figure 7. [0041] Figure 10 shows a bolt 4 having alignment slots 53 to accommodate the aligning pin when the bolt is returned to the working position. Protrusions 54 are still shown on the edges of the flange 7 of the bolt 3 as it is preferable to transmit drive from the input shaft or portion of the bolt to the housing via multiple protrusions 54 rather than the aligning pin, although multiple aligning pins may be provided to negate the requirement for the protrusions 54. [0042] Further variations to the features of the multi-bit tool described are envisaged and are deemed to be within the scope of this invention. For example, the sleeve rotation detent arrangement shown in Figures 1 and 3 can be modified so that the ball is located primarily in the housing and engages with recesses or holes in the sleeve, the ball being spring loaded towards the sleeve by an outer retaining ring. The drop-in pin has been shown as a single domed top pin or a pairing of two balls or of a ball and a roller, although other variations are possible. Where coil springs are shown, other forms of resilient device may be substituted. [0043] Modifications and variations as would be apparent to a skilled addressee are deemed to be within the scope of the present invention.

Claims (5)

1. A multi-bit tool including: a housing incorporating at least two recesses, a bore portion and a drive socket portion axially aligned with the bore, each recess providing a storage location for a tool bit, a sleeve rotatably located in the bore of the housing, the sleeve including a flange portion and a slot portion, the sleeve having a major axis, a bolt slidably located in the sleeve between a bit loading position and a working position, the bolt having a claw, a flange portion and a drive input portion, the claw being provided to accommodate a drive end of a tool bit and provide axial location of the tool bit relative to the bolt, the flange portion including at least one eccentric protrusion extending radially from the flange to engage with the end of one of said at least two recesses to provide rotational location of the bolt relative to the housing, the drive input portion of the bolt receiving drive input to the tool, the flange portion of the bolt driving the housing to thereby transmit the drive input to the drive socket portion of the housing wherein the housing includes at least one sleeve rotation control feature and the sleeve includes at least one sleeve rotation control feature, the two features being mated when a tool bit is selected to lock rotation of the sleeve relative to the housing and the two features being disengaged when a bit is unloaded to permit relative rotation between the sleeve and the housing.

2. A multi-bit tool according to claim 1 wherein there is a sleeve rotation control feature provided in the housing for each recess and a drop-in locking device provided in a sleeve rotation control hole in the sleeve, where the drop-in locking device partially displaces into a sleeve rotation 13 control feature when a tool bit is selected to lock rotation of the sleeve relative to the housing and the drop-in locking device disengages out of the sleeve rotation control feature when a bit is unloaded to permit relative rotation between the sleeve and the housing.

3. A multi-bit tool according to claim 2 wherein the sleeve rotation control hole in the sleeve has an inner hole at its inner end, the inner hole uncovering part of an outer surface of the bolt, the bolt includes a sleeve rotation release recess on the outer surface of the bolt that is aligned with the hole at the inner end of the sleeve rotation control hole when the bolt is fully withdrawn and a sleeve rotation lock actuating ball is provided in the inner end of the sleeve rotation control hole, the dimensions of the drop-in locking device and the sleeve rotation lock actuating ball are such that when the bolt is not fully withdrawn and the sleeve rotation lock actuating ball is not engaging into the sleeve rotation release recess the drop-in locking device is prevented from displacing entirely into the sleeve rotation control hole in the sleeve and therefore remains partially in a said sleeve rotation control feature in the housing, thereby preventing rotation of the sleeve relative to the housing unless the bolt is fully withdrawn and when the bolt is fully withdrawn and the sleeve rotation lock actuating ball is engaging into the sleeve rotation release recess, if the sleeve rotation control hole in the sleeve is not aligned with a said sleeve rotation control feature then the bolt is locked in the fully withdrawn position.

4. A multi-bit tool according to claim 1 wherein the housing includes a sleeve rotation detent feature for each recess and the sleeve includes a radial hole locating a sleeve rotation detent ball and a 14 sleeve rotation detent spring.

5. A multi-bit tool according to claim 1 further including: at least one aligning pin provided in the housing, extending from an inner surface of the housing adjacent an outer end surface of the flange of the sleeve in use, an alignment slot for each recess in the outer end surface of the flange of the sleeve, such that as the bolt is drawn back, the sleeve translates axially with the bolt until the aligning pin is engaging with one of said alignment slots, further alignment slots are provided on a surface of the flange of the bolt to clear or engage with the aligning pin in the housing when the bolt is in a working position.