The present invention relates to modular tools, and in particular a tool holder element for such tools.
The concept of modularity in tools is almost as old as tool use itself. Many ancient tool designs such as hammers, axes, picks and the like comprise a working element fixed to a handle by some means which allows the periodic replacement of one element or the other. Developments in manufacturing processes over the last two hundred years meanwhile have made it possible to develop releasable fixing mechanisms. For example, screw driver heads are commonly available as 6.35 mm (quarter inch) hexagon bits, which may be inserted as required in a standard handle. The bits may be secured magnetically, or by means of a spring loaded ball bearing engaging a groove in the bit. In some contexts meanwhile, the operational constraints extant in that context may tend to lead away from such approaches. In the field of surgical instruments for example, the high forces involved along with sterilisation requirements may tend to indicate an all-in-one approach.
As shown in
Notwithstanding the foregoing, the cost of manufacturing a complete set of stand-alone tools for example as shown in
In this, as in any field where a solid positive engagement between the handle and further elements is a critical requirement, special consideration must be given to the securing mechanism.
Fittings such as that shown in
According to the present invention in a first aspect there is provided a modular tool comprising a tool holder. Thr tool holder is provided with an entry aperture, and adapted to receive a proximal extremity of a tool element in said entry aperture. Thed modular tool further comprises a securing pin assembly comprising a securing pin, and a securing pin channel extending though said tool holder and terminating in the entry aperture. The securing pin is situated in the securing channel so as to slidingly move between a first, retracted position and a second, extended position in which the securing pin protrudes into the entry aperture, whereby in the second position the securing pin traps the proximal extremity of said tool element in the entry aperture, the proximal extremity being unconstrained by the securing pin in the first position. The modular tool further comprises a rocker element having a fulcrum pivotally coupled to the tool holder, a first arm on one side of the fulcrum pivotally coupled to the securing pin, and an eccentric arm on the opposite side of the fulcrum to the first arm, such that either
In a development of the first aspect, the arm upon which pressure biases the securing pin towards the first position, and the tool holder, are provided with a resiliently biased detent such that when sufficient pressure is exerted on the arm, the retention mechanism engages to releasably lock the arm in a first predetermined position, and thereby maintain the securing pin in the first position.
In a further development of the first aspect, the arm upon which pressure biases the securing pin towards the second position, and the tool holder, are provided with a resiliently biased detent such that when sufficient pressure is exerted on the arm, the retention mechanism engages to releasably lock the arm in a second predetermined position, and thereby maintain the securing pin in the second position.
In a further development of the first aspect, the resiliently biased detent comprises a depression formed in the tool holder and a corresponding rounded pin on a resilient projection from the rocker.
In a further development of the first aspect, the resiliently biased detent comprises a first depression formed on one side of the tool holder and a second depression formed on one the of said tool holder and a corresponding first rounded pin on a respective first resilient projection from one side of the rocker and a corresponding second rounded pin on a respective second resilient projection from the opposite side of the rocker, so that the first and second rounded pins are biased towards each other when engaged with said respective first and second depressions.
In a further development of the first aspect, the fulcrum is defined by a further resilient projection from each side of the rocker, each further resilient projection being provided with a fulcrum pin, whereby the fulcrum pin on each further resilient projection is situated on an axis defining the axis of said fulcrum, the tool holder being provided with apertures engaging the fulcrum pins.
In a further development of the first aspect, the first arm is pivotally coupled to the securing pin by means of a fork or hook disposed on the securing pin releasably engaging a pivot pin disposed in the rocker parallel the axis of the fulcrum.
In a further development of the first aspect, fork or hook being formed of a resilient material and so dimensions as to be resiliently retained on said pivot pin.
In a further development of the first aspect, the tool holder having a distal end and a proximal end disposed on a longitudinal axis, wherein the entry aperture comprises a first lateral slot disposed along a second axis in the plane of the first axis and being at an angle of between 10 and 80 degrees to the longitudinal axis, the slot widening from top to bottom, said first slot widening to an entry aperture at the distal end of the first slot, the a securing pin channel extending though the tool holder.
In a further development of the first aspect, the dimensions of the lateral slot vary along the second axis so that the force required to slide a corresponding keyed element of said tool into said lateral slot increases as the corresponding keyed element of said tool progresses into the slot.
In a further development of the first aspect, the tool holder comprises a second slot parallel to the first slot.
In a further development of the first aspect, the second slot is on the same axis as the first slot, and positioned on the distal side thereof.
In a further development of the first aspect, the second slot provides a lateral opening in said tool holder.
In a further development of the first aspect, the tool holder is composed of a synthetic material or a synthetic composite material.
In a further development of the first aspect, the tool holder is composed of a glass fiber reinforced polyarylamide.
The above and other advantages of the present invention will now be described with reference to the accompanying drawings, for illustration purposes only, in which:
As shown in
As shown, the securing pin 221 is a siding fit in channel 220, whereby the securing pin 221 may freely slide back and forth in channel 220 with minimal friction, yet allowing minimal angular deflection between the primary axis of the channel and the primary axis of the securing pin. On this basis, the movement of the first position and second position is linear, along a substantially straight line. As shown, the securing pin is a unitary, monothic element. This approach is advantagoes in achieving mechanical simplicity, and is particularly suited to embodiments based on synthetic materials which may be less well adapted to implementing small load bearing parts.
The tool may comprise a surgical instrument. More particularly for example, the tool may be for surgery of the orthopaedic surgery or bone traumatology. Still more particularly for example the tool may comprise a rasp or reamer or impactor.
The modular tool of
As shown in
As shown, in the second position the securing pin 211 traps the proximal extremity of the working part 250 in said entry aperture.
As shown in
As shown, the first and second arms are broadly parallel to the body of the tool, so that the manual pressure applied to one arm or the other in order to bias it to a respective position tends to move the arm towards the body of the tool.
In alternate embodiments, e.g. placing the rocker on the opposite side of the tool holder with respect to the angle of operation of the securing pin, a configuration may be achieved whereby a pressure on said first arm biases said securing pin towards said second position, and pressure on said second arm biases said securing pin towards said first position.
As shown in
While as shown in
While as shown in
Similarly, the second arm, 233, upon which pressure biases said securing pin towards said first position, and said tool holder, are provided with a resiliently biased detent 236, 242 such that when sufficient pressure is exerted on said second arm, said retention mechanism engages to releasably lock said arm in a second predetermined position, and thereby maintain said securing pin in said first position.
It will be appreciated that either or both detent mechanisms may be provided, and that either or both may implement a spring loaded ball bearing based mechanism, or otherwise, for example as described further below.
In particular, either or both resiliently biased detent comprises a depression formed in said tool holder and a corresponding rounded pin on a resilient projection from said rocker.
As shown in
Similarly as shown in
Accordingly, the either or both resiliently biased detents as described above may comprise a first depression formed on one side of the tool holder and a second depression formed on the other side of said tool holder and a corresponding first rounded pin on a respective first resilient projection from one side of said rocker and a corresponding second rounded pin on a respective second resilient projection from the opposite side of said rocker, so that said first and second rounded pins are biased towards each other when engaged with said respective first and second depressions. Still further, as shown in
It will be appreciated that the rocker may be provided with any combination of rounded pins on resilient projections as described with respect to
It may be noted that the rocker of
In
On this basis, it will be seen that by pressing the lower part of the rocker 430 with sufficient force, the resilient projections 338b (and 438a, not shown) may be brought to disengage their respective resiliently depressions allowing the rocker to pivot about the fulcrum 431 as described above, and to enter the second position as described above.
Resilient projections 337b (and 437a, not shown) may then cause their respective rounded pins 435b and 435a, not shown to resiliently bias their respective depression, such as depression 441b in the tool holder 420, thereby releasable locking the rocker in the second position.
The force required to disengage the upper and/or lower resilient projections as described above and move from one position to the other may be defined by the selection of a suitably resilient material, and by specifying the dimensions of the projections, so as to correspond to a force that may be conveniently applied by a user's thumb, e.g. to the arms of the rocker as described above, without undue effort, but excluding accidental operation.
The force required to disengage the resilient projections of the fulcrum may be defined by the selection of a suitably resilient material, and by specifying the dimensions of the projections, so as to correspond to a force that may exclude decoupling without the deliberate application of significant force, so that once assembled, the tool cannot be accidentally disassembled, even if dropped or brought against another object with substantial force. This may require the use of a dedicated tool or the like.
As shown in
As shown, the rocker, and in particular the arms thereof as described above, may be provided with surface texture, ensuring that sufficient force can be safely and effectively brough to bear on the upper and lower portions of the rocker even if the rocker, or the tool as a whole is wet, dirty or otherwise likely to slip under pressure. This texture may comprise grooves as shown, or any other antislip texture as may occur to the skilled person, including the addition of antislip coatings, rubberized secondary material components, and the like. To further facilitate these actions, the elements may be knurled, grooved, provided with a non-slip coating or otherwise treated to improve the users grip thereon. In particular the securing pin may be knurled, grooved, provided with a non-slip coating or provided with a loop, hook, or other formation adapted to engage the users thumb such that the securing pin may be both pushed forward to block the entry aperture, and pulled back to unblock the entry aperture with the users thumb. As described above, in the second position the securing pin traps the proximal extremity of the tool element in the entry aperture. The skilled person may envisage many possible configuration of the entry aperture, the proximal extremity of the tool element and the securing pin that may achieve this. By way of illustrative example, certain such configurations will not be presented.
It may be noted that the rocker, securing pin and other components as described above have been omitted from this figure for the sake of clarity.
As shown, the tool holder 600 has a distal end 662 and a proximal end 661 disposed on a longitudinal axis 660. The tool holder comprises a first lateral slot 670 disposed along a second axis 671, the second axis in the plane of the first axis 660 and being at an angle θ of between 10 and 80 degrees to the longitudinal axis 660. The slot widens from top to bottom, and further widens to an entry aperture 672 at the distal end of the first slot 670.
The tool holder further comprises a securing pin channel 630 substantially as described above extending though the tool holder and terminating in the entry aperture 672.
As shown in
As shown in
The disposition of the first lateral slot 670 disposed along a second axis 671, the second axis in the plane of the first axis 660 and being at an angle θ of between 10 and 80 degrees to the longitudinal axis 660 means that the application of a force along the tool holder through the working element will force the working element more deeply in to the slot to abut the end wall thereof, rather than tending to push the working element out of the slot.
The tool holder of
The tool holder of
As shown in
The tool holder of
As shown, there is provided a modular tool 1000 comprising a handle 1010, and a tool holder 600 substantially as described above. The handle 1010 comprises a releasable coupling comprising by way of example a threaded ring 1020, the threads of the ring engaging an external helical thread of the cylindrical member of the handle 1010. The threaded ring 1020 is rotatable about the distal end of the member between an extended position which the ring obstructs a slot 1021 opening on one periphery of the distal end of the body, and a retracted position as shown in the emphasised section 1050 in which the ring leaves the slot 1021 opening on one periphery of the distal end of the body unobstructed, into which a tongue element 1090 at the proximal extremity of the tool holder may be inserted. When the ring is rotated about the cylindrical member, it progresses along the length thereof and whilst progressing lengthwise and rotating, obstructs a slot 1021 to trap the tool holder in place.
The handle may optionally be provided with an angle datum such as a radial line on the guard plate, or a radial lumen through which a bar may by inserted.
As such the tool holder may further comprise a tongue element provided at a proximal end thereof, the tongue being widening from its junction with the tool holder.
The tool holder may be associated with a handle at the proximal end of the tool holder, and a tool at the distal end of the tool holder releasably coupled thereto by means of a tongue of the tool engaged in the first slot and trapped by the securing pin, where the handle 1010 has a primary axis A and the tool 1000 has a primary axis B, whereby the tool holder 1000 is configured to establish a lateral offset A between the two primary axes.
The tool holder may additionally or alternatively establish an angular offset between the axes.
Alternatively a Hudson fitting as known in the state of the art, or any other convenient mechanism may be used to secure the tool holder to the handle. The handle may also be integral to the tool holder.
Meanwhile, the tool holder comprises at a distal end a first lateral slot disposed along a second axis, the second axis in the plane of the first axis and being at an angle of between 10 and 80 degrees to the longitudinal axis, the slot widening from top to bottom, the first slot widening to an entry aperture at the distal end of the first slot, the tool holder further comprising a securing pin channel extending though the tool holder and terminating in the entry aperture, such that a securing pin may be inserted through the pin channel so as to trap a keyed element inserted in the widened part of the first slot, substantially as described above, to provide a releasable coupling between the tool holder 600 and working part 1050. Any of the other variants or optional features presented above may be adopted, or not, in a modular tool along the lines of that of
As shown, the handle further comprises an optional guard plate 1002 at the proximal end thereof. Such a guard plate may serve to protect the hand of a user when gripping the handle 1020 from blows struck against the proximal end thereof with a hammer, mallet or the like, for example where the tool or working part 1050 is a chisel, reamer or other such tool requiring a percussive application.
One field in which a handle as described may be appropriate is that of surgical instruments, such that the modular tool as a whole may comprise or constitutes a surgical instrument. More particularly, the modular tool may be for orthopaedic surgery or bone traumatology. More particularly, the modular tool may be for surgery of the hip, shoulder or knee. More particularly, as shown, the working part 1050, and thus the modular tool as a whole 1050 comprises a rasp or reamer or impactor. It will be appreciated that in line with the many fields of application and associated tool types that may be envisaged, many different possible working parts 1050 may be envisaged, for use with a single handle in accordance with embodiments as described above. Further examples of possible working parts, and resulting modular tools, include a curved rasp 1050b, osteotome 1050c and many other tools as will readily occur to the skilled person.
The tool holder of the present invention may be formed of any material. In particular, it may be formed of steel, aluminium, titanium or any other suitable metal or alloy. It may also be formed of a thermoplastic or other synthetic material. It may in particular be formed from a polyamide, for example a polyarylamide. The synthetic material may comprise additional components such as a filler, swelling agent and the like. It may still further be formed of a synthetic composite material, comprising a glass, carbon fibre, carbon nanoparticle or any other material exhibiting a high tensile strength, in a matrix of a synthetic material, such as any of those listed above. In certain embodiments, the tool holder may be composed of a glass fibre reinforced polyarylamide, such as for example that marketed by the Solvay corporation under the trademark “Ixef GS 1022”. The tool holder may be formed of different materials in different regions, including metal parts and synthetic parts. The handle may also comprise voids for the purpose of economy of material, reduced weight and so on.
Where the tool holder is incorporated in a modular tool as shown in
In certain embodiments, the angle of insertion of the working part in the tool holder may be envisaged.
In particular, the tool holder 1100a comprises a first lateral slot 670 disposed along a second axis 671, the second axis in the plane of the first axis 670 and being at an angle θ of approximately 45 degrees to the longitudinal axis 670. The slot widens from top to bottom, and further widens to an entry aperture 672 at the distal end of the first slot 670.
The working part is provided with a keyed element 691. The keyed element 691 is dimensioned that it may be inserted into the entry aperture 672.
The “push and slide” insertion action implied by the arrangement of
As discussed above, the disposition of the first lateral slot 670 disposed along a second axis 671, the second axis in the plane of the first axis 660 and being at an angle θ of between 10 and 80 degrees to the longitudinal axis 660 means that the application of a force along the tool holder through the working element will force the working element more deeply in to the slot to abut the end wall thereof, rather than tending to push the working element out of the slot.
While as discussed with respect to
In particular, the toolholder 1100b (corresponding substantially to toolholder 600 as described above) comprises a first lateral slot 1170b corresponding substantially to first lateral slot 670 as described above) disposed along a second axis 1171b (corresponding substantially to second axis 671 as described above), the second axis in the plane of the first axis 660 and being at an angle θ of approximately 70 degrees to the longitudinal axis 1160b. The working part is provided with a keyed element 1191b. The insertion action implied by the arrangement of
It may be noted that in the embodiment of
In particular, the tool holder 1100c (corresponding substantially to toolholder 600 as described above) comprises a first lateral slot 1070c corresponding substantially to first lateral slot 670 as described above) disposed along a second axis 1171c (corresponding substantially to second axis 671 as described above), the second axis in the plane of the first axis 660 and being at an angle θ of approximately 45 degrees to the longitudinal axis 1110c (and 80 degrees to the longitudinal axis of the notional handle 660). The working part is provided with a keyed element 1191.
The insertion action implied by the arrangement of
It may be noted that in the embodiment of
As such, there is provided a tool holder for a modular tool in which the tool holder may be releasably coupled to a working part such as a rasp, reamer or impactor. The coupling comprises a slot closed at both extremities, and widening to an entrance aperture at one extremity, into which a keyed element of the tool may be inserted, and slid to the opposite extremity of the slot. The modular tool defines a securing pin channel through its body, terminating at the entry aperture such that a securing pin inserted into the channel block the entry aperture and locks the keyed element of the tool in place once inserted.
Accordingly there is provided a tool holder for a modular tool is arranged to receive a tool element which may be inserted laterally by sliding a dovetailed part of the tool into a slot on the tool holder. A securing pin may be inserted through the body of the tool holder so as to enter the slot, thereby locking the tool element in place. The locking pin is pivotally mounted to one side of a rocker, the rocker being pivotally coupled to the tool holder body so that by cycling the rocker from one position to another, the locking pin is moved back and forth through the body of the tool holder to engage or disengage the tool element. The rocker may be of a resilient material so as to clip into position on the tool holder. It may be provided with features such as protusions adapted to resiliently engage corresponding features on the tool holder so as to latch in one position, or the other, or both.
It will be understood that the configurations and/or approaches described herein are exemplary in nature, and that these specific embodiments or examples are not to be considered in a limiting sense, because numerous variations are possible. The specific routines or methods described herein may represent one or more of any number of processing strategies. As such, various acts illustrated and/or described may be performed in the sequence illustrated and/or described, in other sequences, in parallel, or omitted. Likewise, the order of the above-described processes may be changed.
The subject matter of the present disclosure includes all novel and non-obvious combinations and sub-combinations of the various processes, systems and configurations, and other features, functions, acts, and/or properties disclosed herein, as well as any and all equivalents thereof.
Number | Date | Country | Kind |
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20306248.4 | Oct 2020 | EP | regional |
Filing Document | Filing Date | Country | Kind |
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PCT/EP2021/072886 | 8/18/2021 | WO |