CABLE TIE TENSIONING AND CUT-OFF TOOL

RELATED APPLICATIONS

The present application claims the benefit of European (EP) Patent Application No. 22208441.0, filed Nov. 18, 2022, entitled “CABLE TIE TENSIONING AND CUTOFF TOOL,” and to European (EP) Patent Application No. 22211262.5, filed Dec. 2, 2022, entitled “A CABLE TIE TENSIONING AND CUT-OFF TOOL.” The entireties of European (EP) Patent Application No. 22208441.0 and European (EP) Patent Application No. 22211262.5 are expressly incorporated herein by reference.

FIELD OF THE DISCLOSURE

The present disclosure relates to hand-held tensioning and cutting tools and in particular, to an improved hand tool for tensioning and cutting cable ties.

BACKGROUND

Cable ties, also known as zip ties or hose ties, are widely used in a variety of environments and applications. For example, cable ties may be used to securely bundle a plurality of wires, cables or conduits such as those found in the automotive industry. Also, cable ties may be used to secure articles to rigid structures (e.g. a chassis), but may also be utilised as hose clamps. Typically, a cable tie comprises a tie head portion and a tie tail portion of various lengths that is integrally formed with the head portion. During use, the tie tail is threaded through the tie head so as to encircle the articles to be bound or secured. The tie tail section is usually provided with teeth that engage with a pawl provided in the tie head and forming a ratchet so that, as the free end of the tie tail is pulled, the cable tie tightens and does not come undone. Once the tie tail of the cable tie has been pulled through the tie head and past the ratchet, it is prevented from being pulled back, thus, the resulting loop may only be pulled tighter. Some cable ties may include a tab that can be depressed to release the ratchet so that the cable tie can be loosened or be removed and possibly reused.

A cable tie tensioning device, also known as cable tie tool or cable tie gun, may be used to install cable ties and apply a predefined degree of tension, as well as, cut off the extra tail. Preferably, the cut tie tail is flush with the tie head portion so as to avoid sharp edges, which might otherwise cause injuries. Light-duty tools may be operated by simply and repeatedly squeezing the handle and trigger with the fingers until a desired tension of the cable tie has been reached to then cut off the tail section of the tightened cable tie. Heavy-duty or automated tools may be powered, for example, by compressed air or a solenoid (i.e. actuator) to assist the user when operating the tool.

Available tools can be rather inaccurate in the desired tension applied to the cable tie, as well as, in leaving protruding remnants of the cut tie tail portion. As a result, higher-quality tools have become rather complex (and expensive) in order to achieve a desired tensioning at sufficient accuracy, as well as, a consistently clean and flush cut-off section.

As mentioned before, the accuracy of the selected cable tension and the reliability of the cut-off threshold can be a crucial factor when using cable ties to fasten or fix specific components. On the other hand, the cost of manufacture, wear resistance and durability, as well as, its ease of use and user handling are equally as important. In particular, the ease of use and user experience provided by available tools are perceived to be less important features that are not addressed satisfactory, potentially causing discomfort or even injury to the user.

Accordingly, it is an object of the present disclosure to provide an improved, as well as simplified cable tie tool for tensioning and cutting cable ties, thus, reducing manufacturing costs while improving durability and ease of use.

SUMMARY

Aspects of the disclosure are set out in the independent claim(s). Dependent claims describe optional features.

According to an aspect of the disclosure, there is provided a tool for tensioning and severing an elongate cable tie having a tie head portion and a tie tail portion, said tool comprising: a pistol-shaped housing, having a barrel portion extending between a distal housing end portion and a proximal housing end portion along a longitudinal axis and a handle portion extending away from said barrel portion in a direction different to said longitudinal axis; a trigger mechanism, comprising an elongate trigger member extending away from said barrel portion operably forward of said handle portion and configured to move toward and away from said handle portion; a tension mechanism, comprising a pawl link provided slidably reciprocatingly within said barrel portion along said longitudinal axis and operably coupled to said trigger mechanism, configured to grippingly engage the cable tie and apply tension to the tie tail when moving said elongate trigger member toward said handle portion, during use; a locking mechanism, provided within said barrel portion and operably coupled with said tension mechanism, comprising a locking lever, having a stop member at a proximal lever end and a contact portion at a distal lever end, said locking lever is arranged parallelly adjacent to said pawl link and pivotally coupled to a first fulcrum pin of said pawl link, so as to allow rotation of said locking lever about said first fulcrum pin relative to said pawl link between an unlocked position and a locked position, configured to stop operation of and lock said tension mechanism at a predetermined tension of the tie tail; a cut-off mechanism, provided within said barrel portion and operably coupled with said trigger mechanism and said locking mechanism, configured to cut the tie tail when said locking mechanism is lockingly actuated, said cut-off mechanism comprising: a cutting lever, having a blade member at a distal cutting lever end, arranged parallelly below said pawl link and pivotally coupled at a second fulcrum pin of said housing, so as to allow rotation of said cutting lever about said second fulcrum pin relative to said housing between an upper position, cuttingly engaging with the cable tie, and a lower position, disengaged from the cable tie; and a cutting linkage, operably coupling a proximal cutting lever end with said trigger mechanism, so as to rotate said cutting lever between said upper position and said lower position at a predetermined condition during actuation of said trigger mechanism; an adjustable biasing mechanism, adapted to provide a biasing load to any one of said trigger mechanism, said tension mechanism and said cut-off mechanism, comprising: a second biasing member, provided within said barrel portion; a lever link, pivotably mounted to a third fulcrum pin of said housing and coupled to said second biasing member via a first end portion, so as to translate a linear movement from said cutting linkage into a rotational movement of said lever link about said third fulcrum pin, and a cam link, operably coupled between a second end portion of said lever link and said cutting linkage, adapted to provide a predetermined resistance profile to said cutting linkage when moving said cutting lever from said lower position towards said upper position.

The use of a cutting linkage directly coupling the cutting lever with the trigger mechanism provides for a simplified and more hardwearing (i.e. more reliable) assembly with a reduced number of parts compared to tools with similar capability, that are known to generally have a relatively complicated mechanism utilising, for example, a cooperating cut-off cam and dog bone cam shaft operably coupled with a rack and biased pinion. Thus, the present disclosure provides for reduced overall manufacturing costs and improved durability. Further, the cam link improves the ease of use by providing a favourable or optimised resistance profile (i.e. predetermined by the contour of its flanks) to the user when actuating the trigger lever. In particular, the threshold transition zone provided on the cam surface of the cam link is cooperating with the cutting linkage of the cutting mechanism so as to increase the initial trigger lever resistance following with a reduced trigger lever resistance minimising the user effort through the final cutting phase and thus significantly improve the ease of use and user experience when operating the tool.

Advantageously, said cam link is rotatably coupled within said housing and configured to rotate between an upward position, stoppingly engaging with said locking lever, and a downward position, disengaged from said locking lever. Preferably, said cam link comprises a finger member extending forward and upwards from a distal surface of said cam link, adapted to contactingly engage with said locking lever. Even more preferably, said cam link comprises a cam surface configured to operably engage with a cam follower of said cutting linkage. Even more preferably, said cam surface comprises a transition portion having an opening flank, adapted to gradually increase resistance to movement of said cam follower, and a closing flank, adapted to gradually reduce resistance to movement of said cam follower, when moving said cutting lever from said lower position to said upper position.

Advantageously, said proximal cutting lever end comprises a contact portion configured to engage with a stopping plate provided with said housing. Preferably, said stopping plate is arranged, so as to, stop rotational movement of said cutting lever when moving from said upper position to said lower position.

Advantageously, said cutting linkage comprises a pivot link and a sliding link operably coupled so as to translate a force generated through an inner trigger link of said trigger mechanism from a direction towards said distal housing end portion along said longitudinal axis into a rotational movement of said cutting lever about said second fulcrum pin. Preferably, said sliding link is operably coupled within said housing so as to allow sliding movement in a direction parallel to said longitudinal axis. Even more preferably, said pivot link is rotatably coupled with said sliding link via a pivot pin.

Advantageously, said cam follower comprises said pivot pin, adapted to operably engage with said cam surface.

Advantageously, said predetermined condition is a predetermined tension of the tie tail transmitted via said inner trigger link, during use.

Advantageously, said second biasing member is operably coupled with said lever link so as to biasingly counteract rotational movement of said lever link about said third fulcrum pin.

Advantageously, said cutting lever is biased towards said lower position.

Advantageously, comprising a preload control mechanism configured to selectively change said biasing load provided by said second biasing member in predetermined steps. Preferably, said preload control mechanism comprises a lead screw mechanism operably coupled between an adjustment knob and said second biasing member and adapted to convert a rotational movement of said adjustment knob into a change of said biasing load provided by said second biasing member. Even more preferably, said preload control mechanism comprises a gear mechanism operably coupled between said adjustment knob and said lead screw mechanism, configured to provide a predetermined transmission ratio between rotational movement of said adjustment knob and a resulting rotational movement of a threaded shaft of said lead screw mechanism. Even more preferably, said a gear mechanism is a spin multiplier.

BRIEF DESCRIPTION OF THE DRAWINGS

An exemplary embodiment of the disclosure is explained in more detail hereinbelow with reference to the figures:

FIG. 1 illustrates perspective (a) front view and (b) rear view of an embodiment of the cable tie tool of the present disclosure;

FIG. 2 illustrates a (a) side view, (b) front view, (c) top view and (d) rear view of an embodiment of the cable tie tool of the present disclosure;

FIG. 3 illustrates a cross-sectional perspective rear side view of an embodiment of the housing, without the tool mechanism as shown in FIG. 5;

FIG. 4 illustrates a cross-section side view along A-A of the cable tie tool of FIG. 2 (c);

FIG. 5 illustrates a perspective rear view of an embodiment of the assembled cable tie tool with the housing removed;

FIG. 6 illustrates a perspective rear view of the cable tie tool of FIG. 5 but exploded into the different groups of the mechanism;

FIG. 7 illustrates the trigger mechanism of an embodiment of the cable tie tool, (a) in a perspective side view, (b) a partially cross-sectional perspective side view and (c) an exploded perspective side view;

FIG. 8 illustrates an embodiment of the tensioning mechanism group (a) in a perspective left side view with one pawl link member moved away, and (b) in a perspective right side view;

FIG. 9 illustrates a perspective close-up view of the distal end portion of the pawl link and exploded gripping pawl (a) in a perspective left side view with one pawl link member removed, (b) in a perspective right side view with one pawl link member removed, (c) a perspective left side view of an embodiment of an exploded pawl link assembly including both pawl link members, and (d) a perspective left side view of an alternative embodiment of an exploded pawl link assembly comprising a rotatably coupled pawl biased towards the backing plate;

FIG. 10 illustrates a side view of the tensioning mechanism (and part of the locking mechanism) coupled with the trigger mechanism;

FIG. 11 illustrates (a) a perspective side view of an embodiment of the locking mechanism coupled with the tensioning mechanism (one pawl link member has been removed) and (b) an exploded perspective view of the locking mechanism (without the rack member) and tensioning mechanism;

FIG. 12 illustrates an embodiment of the locking mechanism (a) in an unlocked position, with the cam link moved into engagement with the locking lever counteracting the bias on the proximal lever end, and (b) in a locked position with the cam link rotated away out of engagement with the locking lever, with arrows indicating direction of movement of the locking lever and forces provided by biasing members;

FIG. 13 illustrates a perspective side view of an embodiment of (a) the cut-off mechanism operably coupled with the biasing mechanism and (b) an exploded cut-off mechanism including the lever link and cam link coupling the cutting mechanism with the biasing mechanism;

FIG. 14 illustrates an embodiment of the locking mechanism and a portion of the cutting mechanism coupled with the locking mechanism (a) in an unlocked position (predetermined tie tail tension not reached) and (b) in a locked position (predetermined tie tail tension reached and tail cutting executed), with arrows indicating movement of the locking lever, lever link, cam link and cutting linkage;

FIG. 15 illustrates an perspective side rear view of an embodiment of the cutting mechanism operably coupled with the trigger mechanism and the exploded adjustable biasing mechanism;

FIG. 16 illustrates a perspective side rear view of (a) an embodiment of the assembled adjustable biasing mechanism of FIG. 15 and (b) an alternative embodiment of the assembled adjustable biasing mechanism;

FIG. 17 illustrates an example embodiment of the blade guard (a) in a perspective side view and (b) in a cross sectional side view;

FIG. 18 illustrates close up view of (a) the rack member with a plurality of triangular teeth, (b) the stop member with a plurality of triangular teeth complementary to the teeth of the rack member, and (c) the teeth of the stop member lockingly engaged with the teeth (or spaces) of the rack member;

FIG. 19 illustrates a detailed cross sectional close up view of the distal end portion of an embodiment of the tool with (a) the pawl link in its starting (resting) position and the pawl engaged with a portion of the distal housing pushing the pawl back down and away from the backing plate (ready to receive the cable tie tail) the pawl link is retracted, and (b) the pawl link is pulled back so that the pawl can move towards the backing plate (pushed by the spring along the guide apertures);

FIG. 20 illustrates a close-up view of the cam link coupled between the lever link and the cutting linkage (one half of lever link and cutting linkage removed for clarity); and

FIG. 21 illustrates the cam link (a) in a perspective rear view and (b) in a side view.

DETAILED DESCRIPTION

The described example embodiment relates to a hand-held tensioning and cutting tool such as a cable tie tool for use with cable ties. However, the disclosure is not limited to hand-held devices and may be used for any tool suitable for tensioning and cutting cable ties.

Certain terminology is used in the following description for convenience only and is not limiting. The words ‘right’, ‘left’, ‘lower’, ‘upper’, ‘front’, ‘rear’, ‘upward’, ‘down’, ‘downward’, ‘above’ and ‘below’ designate directions in the drawings to which reference is made and are with respect to the described component when assembled and mounted (e.g. in situ). In particular, the designated directions used in the description are with respect to the hand held tool held by the user in a normal, upright position, i.e. the handle portion pointing downwards and the barrel portion pointing forward and away from the user. It is understood that the tool may be used in any other orientation suitable for the job at hand, though, for simplicity, the designated directions are used when the tool is in a “normal” orientation. The words ‘inner’, ‘inwardly’ and ‘outer’, ‘outwardly’ refer to directions toward and away from, respectively, a designated centreline or a geometric centre of an element being described (e.g. central axis), the particular meaning being readily apparent from the context of the description.

Further, as used herein, the terms ‘connected’, ‘attached’, ‘coupled’, ‘mounted’ are intended to include direct connections between two members without any other members interposed therebetween, as well as, indirect connections between members in which one or more other members are interposed therebetween. The terminology includes the words specifically mentioned above, derivatives thereof, and words of similar import.

Further, unless otherwise specified, the use of ordinal adjectives, such as, ‘first’, ‘second’, ‘third’ etc. merely indicate that different instances of like objects are being referred to and are not intended to imply that the objects so described must be in a given sequence, either temporally, spatially, in ranking or in any other manner.

Through the description and claims of this specification, the terms ‘comprise’ and ‘contain’, and variations thereof, are interpreted to mean ‘including but not limited to’, and they are not intended to (and do not) exclude other moieties, additives, components, integers or steps. Throughout the description and claims of this specification, the singular encompasses the plural unless the context otherwise requires. In particular, where the indefinite article is used, the specification is to be understood as contemplating plurality, as well as, singularity, unless the context requires otherwise.

Features, integers, characteristics, compounds, chemical moieties or groups described in conjunction with a particular aspect, embodiment or example of the disclosure are to be understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith. All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive. The invention is not restricted to the details of any foregoing embodiments. The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract or drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

Referring now to FIGS. 1 to 4, an example embodiment of the cable tie tool 100 incorporating the principles of the present disclosure(s) is preferably pistol shaped and intended to be hand-held by the user. The cable tie tool 100 comprises a housing 102 having a barrel portion 104 extending along a longitudinal axis 110 between a distal housing end portion 106 and a proximal housing end portion 108. A handle portion 112 extends away from the proximal housing end portion 108 in a direction intersecting with the longitudinal axis 110, for example, at an angle between 60° and 90° with respect to the longitudinal axis 110. The housing 102 may further comprise a trigger housing portion 206, a front cover portion 114 (or nose piece) provided at the distal housing end portion 106. The front cover portion 114 may be an integral part of the housing 102. An adjustment knob 630 and a biased locking switch 636 is provided at the proximal housing end portion 108.

FIGS. 2 (a) to (d) shows the cable tie tool 100 in respective side-view, front-view (distal end), top-view and rear-view (proximal end).

FIG. 3 shows an illustration of an embodiment of the housing 102 in a cross-sectional perspective side rear view providing further details of the interior wall structure of the housing 102. In particular, the interior of the housing 102 provides various engagement portions (e.g. blocks), cam guides, slots or blocks (e.g. stopping plate 124) for various parts of the tool mechanism(s), as well as, receptacles for fasteners.

The cable tie tool 100 mechanism is operably embedded into the housing 102 and, for a better understanding, has been divided into separate functional groups that are operably coupled to each other so as to provide the desired functions of the tool 100. The mechanism of the cable tie tool 100 can be grouped into the trigger mechanism 200, mostly embedded within the handle portion 112 and trigger housing portion 206 and is adapted to be moved by the user's hand during operation, the tension mechanism 300, embedded within the barrel portion 104 and adapted to grippingly engage the cable tie tail and apply a predetermined maximum tension, the locking mechanism 400, embedded within the barrel portion 104 and adapted to lock the trigger mechanism 200 and tensioning mechanism 300 at the predetermined (i.e. selected) maximum tension applied to the cable tie tail, the cut-off mechanism 500, partly embedded within the barrel portion 104 and at the distal housing end portion 106 of the tool 100 and configured to cut through the cable tie tail when the predetermined tension applied to the cable tie tail is reached, and the adjustable biasing mechanism 600, partly embedded within the proximal housing end portion 108 of the barrel portion 104 and adapted to adjust the biasing force defining the maximum tension applied to the cable tie tail, during use.

FIG. 4 illustrates a cross-sectional side view of the cable tie tool 100 showing the different interconnected functional groups of the whole mechanism. Reference numerals only point to the general area of the respective group. Also, respective functional groups 200, 300, 400, 500 and 600 are partially interconnected and a part of one group may also be a component of, or at least operably coupled with, another group. FIGS. 5 and 6 show perspective rear views (assembled and exploded) of the tool mechanism without the housing 102, trigger housing portion 206, front cover portion 114 and blade guard 526. For ease of understanding, each functional group is now described separately.

Trigger Mechanism

Referring now to FIG. 7, the trigger mechanism 200 is the main actuator of the cable tie tool 100. In operation, the user grips the handle portion 112 with the palm of one hand and uses the fingers of that hand to squeeze the trigger lever 202 towards the handle portion 112. When releasing the pressure provided by the user's fingers, the trigger lever 202 is urged back into its starting position via a biasing member 246 operably embedded into the handle portion 112 and coupled to the handle lever 224. Repeated movement of the trigger lever 112 will pull the tie tail back and apply a tension.

The trigger mechanism 200 is partially integrated into the handle portion 112 of the housing 102. An elongate trigger lever 202 is located forwardly of the handle portion 112 and pivotably mounted within the housing 102 at its proximal (or upper) end 227 so as to allow movement about a substantially horizontal pivot axis 208. The trigger lever 202 may include two substantially parallel spaced side faces 210a,b and a front face 212 forming a generally U-shaped profile with an elongate recess 214. Thus, the trigger lever 202 is movable from an initial forward position to a final rearward position and back to its initial forward position. An inner trigger link 204 extends upwardly within the elongate recess 214 of the trigger lever 202, a lower link end 216 of the inner trigger link 204 is pivotally joined to the trigger lever 202 for pivot movement about a substantially horizontal pivot axis 218. The upper link end 220 comprises an elongate aperture 222 suitable to operably link to the cutting mechanism 500 (described in more detail in a following section). The elongate aperture 222 is of acuate shape so as to allow pivot movement of the inner trigger link 204 while the sliding link 518 is restricted (by housing cam guides) to sliding movement parallel to the longitudinal axis 110. A handle lever 224 is pivotally coupled at its lower (distal) lever end 226 at a pivot axis 242 within the handle portion 112 of housing 102 and its upper (proximal) lever end 228 is operably coupled to a proximal end of a pawl link 302 of the tension mechanism 300 (described in more detail in a subsequent section). The handle lever 224 is pivotally movable about its pivot axis 242 between a forward position (relative to the handle portion) and a rearward position within the handle portion 112. The handle lever 224 is biased towards its forward position by biasing member 246, such as, for example, a coil spring or a leaf spring or a torsion spring as shown in FIG. 7, or any other spring element suitable to urge the handle lever 224 into its forward position.

A forward end 232 of a short link 230 is pivotally joined to the inner trigger link 204 and a rearward end 234 of the short link 230 is pivotally joined to the handle lever 224. Each one of the forward end 232 and the rearward end 234 are configured to allow pivot movement about respective pivot axes 236 and 238. A trigger bearing 240a,b (see FIG. 5, comprising left and right bearing) may be provided at the coupling of the upper leaver end 228 of the handle lever 224 with the tension mechanism 300 (i.e. mounted to the proximal end of the pawl link 302 and engaged with the upper lever end 228 via an elongated aperture 244), movement of which is limited to a horizontal, linear reciprocal movement relative to the housing 102, i.e. the housing 102 is provided with a first cam or guide surface 116 (see FIG. 3) adapted to guidingly engage with respective trigger bearing 240a,b such that pivotal movement of the handle lever 224 about its pivot axis 242 is translated into to a linear movement of the operably coupled pawl link 302.

Tension Mechanism

The tension mechanism 300 is operably linked to and actuated by the trigger mechanism 200 in order to securely grip the inserted tie tail of the cable tie and pull the engaged tie tail backwards (i.e. towards the proximal end portion of the tool 100), thus, tightening the cable tie around the bundle of components until a predetermined maximum tension of the tie tail is reached.

Referring now to FIG. 8, the tension mechanism 300 comprises a pawl link 302 mounted for horizontal, linear reciprocal movement relative to the housing 102. The pawl link 302 is guidingly supported for linear movement via suitable link bearings 318 configured to operably engage with a suitable second cam surface or guide 118 of the housing 102 (see FIG. 3). A gripping pawl 310 is operably mounted to the distal end portion 306 of the pawl link 302. Here, in this particular example embodiment, the gripping pawl 310 is slidably attached to the pawl link 302, so as to allow sliding movement between a lower, rearward (i.e. more proximal) position and an upper, forward (more distal) position relative to the pawl link 302. The distal end portion 306 of the pawl link 302 further comprises a backing plate 314 arranged so as to trappingly or grippingly engage the tie tail in cooperation with the gripping pawl 310. A spring member 316 provides a bias of the gripping pawl 310 towards its upper, forward, position, i.e. towards the backing plate 314. Here, any suitable biasing member may be used to provide a spring bias. A coil spring 316a may be embedded in a recess of a spring block 316b and arranged so as to push against the gripping pawl 310 from a proximal side, thus urging the gripping pawl 310 towards its upper, forward position (see FIG. 9 for more detail). In this particular example, a recess is formed between adjacent spring block 316b and gripping pawl 310 aligned such that the spring 316a engages with the gripping pawl 310 at an angle towards the backing plate 314.

As shown in more detail in FIGS. 9 (a) to (c), the distal end portion 306 of the pawl link 302 comprises two pairs of parallelly arranged guide apertures 304a and 304b adapted to receive respective pairs of guide member 308a and 308b of the gripping pawl 310 and defining the predetermined guide path of the gripping pawl 310 relative to the pawl link 302.

In an embodiment, the pawl link 302 comprises two parallel arranged symmetrical pawl link members 302a, 302b (see FIG. 9 (c)) configured to sandwichingly mount the gripping pawl 310, as well as, spring member 316 therebetween. In this particular case, the gripping pawl 310 comprises two pairs of guide members 308a and 308b, each pair protruding into opposite directions of the other, which are then received by respective pairs of guide apertures 304a, 304b of the pawl link members 302a, 302b. It is understood that the guide aperture(s) 304a, 304b may define any suitable guide path (e.g. linear or curved), so as to optimise contact engagement between the backing plate 314 the inserted tie tail and the gripping pawl 310. Furthermore, as shown in FIG. 9(d), instead of the slidable gripping pawl 310, a pivotable gripping pawl 311 and respective bias, e.g. torsions spring 317, may be used within the same pawl link members 302a, 302b.

As illustrated in FIG. 10, a proximal end portion 320 of the pawl link 302 comprises a bearing pin 322 configured to receive the trigger bearings 240a,b, as well as, pivotally couple with the upper lever end 228 via its elongated aperture 244. The elongate aperture 244 is shaped so as to allow an arcuate trajectory of the handle lever 224 about its pivot axis 242.

Furthermore, and with reference to FIGS. 19(a) and (b), the gripping pawl 310 may comprise a protrusion 326 projecting from its distal end and configured to engage with a respective engagement portion 120 of the distal housing end portion 106 so as to hold the gripping pawl 310 in its lower position against the biasing force of the spring member 316a when the pawl link 302 is in a starting position (i.e. forward position, see FIG. 19(a)). In this position, the gripping pawl 310 and the backing plate 314 provide an open gap between backing plate 314 and gripping pawl 310 allowing cable tie tails to be placed into the tool 100. When the trigger lever 202 is pulled back, the pawl link 302 is moved back, thus, disengaging gripping pawl 310 from the engagement portion 120, allowing the spring 316a to biasingly move the gripping pawl 310 forward and up towards the backing plate 314 (see FIG. 19(a)). In this particular example, the protrusion 326 is a sloped surface (downward slope) that matingly engages with a corresponding sloped surface of the engagement portion 120.

Locking Mechanism

The locking mechanism 400 is operably coupled with the tension mechanism 300 and its function is to lock the movement of the pawl link 302 (i.e. interrupt the backward movement of the pawl link 302) and initiate the actuation of the cutting mechanism 500 when reaching a predetermined tension applied to the tie tail during use. FIG. 10 shows the arrangement of the three involved functional groups, i.e. trigger mechanism 200, tension mechanism 300 and locking mechanism 400, within the tool 100 (housing 102 and other functional groups were removed for simplicity).

Referring now to FIGS. 11 and 12, the locking mechanism 400 is shown in combination with the tension mechanism 300. The locking mechanism 400 comprises a locking lever 402 arranged adjacent to and substantially in parallel with a proximal section of the pawl link 302 between a proximal lever end 406 and a distal lever end 410. A contact surface 408 is facing downwards from its distal lever end 410 and a stop member 404 (i.e. a plurality of teeth) is protruding upwards from its proximal lever end 406 (i.e. in an opposite direction of the contact surface 408). The locking lever 402 is pivotally coupled with the pawl link 302 via a fulcrum pin 412, thus, allowing the locking lever 402 to rotate about the fulcrum pin 412 with respect to the pawl link 302 between an engaged, locked position (i.e. teeth of stop member 404 lockingly engage with corresponding teeth of rack member 414) and a disengaged, unlocked position. In this particular example embodiment, the fulcrum pin 412 of the locking lever 402 is offset with regards to a distal and proximal end portions 406, 410 of the locking lever 402 (i.e. the fulcrum pin is 412 higher with respect to the distal and proximal end portions 406, 410), which is provided via an arcuate midsection of the locking lever 402.

The lower contact surface 408 of the distal lever end 410 is configured to contactingly engage with a stopping plate 124 provided with the housing 102. A rack member 414 is mounted to the housing 102 and within the biasing mechanism group 600 and orientated so as to operably face in a direction of the stop member 404 (e.g. an array of equidistantly arranged teeth). This allows locking engagement between the teeth of the stop member 404 and the teeth of the rack member 414 when the locking lever 402 is moved upwards.

A lever support member 418 is mounted to the proximal end portion 320 of the pawl link 302 and configured to support the proximal lever end 406 when in its unlocked position. The lever support member 418 comprises a spring element 420 operably embedded within the support surface 422 of the lever support member 418 and configured to bias the proximal lever end 406 towards its locked position (i.e. towards the rack member 414). This bias is counteracted by a finger member 540 of a cam link 538 coupled with the cutting linkage 514 and the lever link 602 of the biasing mechanism 600. In an embodiment, the locking lever 402 and lever support member 418 are “sandwiched” or operably installed between the two assembled pawl link members 302a and 302b (see FIG. 11(b)).

FIG. 12 illustrates the degrees of movement of the separate components of the locking mechanism 400 when moving from the unlocked position into the locked position. In particular, as shown in FIG. 12(a), the finger member 540 of the cam link 538 counteracts the force applied to the proximal lever end 406 by the embedded coil spring 420, thus, holding the locking lever 402 in its unlocked position (disengaged from the rack member 414). When the cutting lever is pivoted through the cutting linkage 514, the cam link is rotated into its downward position by the rotating lever link 602 and the “pushing” pivot pin 522 of the sliding link 518, and the force applied by the coil spring 420 rotates the locking lever 402 about fulcrum pin 412 into engagement with the rack member 414 (see FIG. 12(b)).

In particular, the downward movement of the cam link finger member 540 is initiated by the sliding link 518 moving forward, the cutting lever 502 rotating downwards and the lever link rotating against its coils spring 608, thus, the finger member 540 moving away from the distal lever end 410 and allowing the pivot pin 522 of the pivot link 518 to slide over the cam surface threshold 542 rotating the locking lever 402 about its fulcrum pin 412 until the stop member 404 (i.e. teeth) engages with the rack member 414. When the cutting lever 502 rotates back, the pivot pin 522 moves back over the cam threshold 542 rotating the cam link 538 back about its pivot point 544 and rotating the lever link 602 away from the coil spring 608. The finger member 540 moves back up into contact with the distal lever end 410 urging the proximal lever end 406 out of locking engagement with the rack member 414 and back into contact with the lever support member 418.

The simple arrangement of the few components of the locking mechanism 400 provides a robust and highly repetitive lever mechanism that forms the basis for a consistently accurate predetermined maximum tension of the cable tie tail (i.e. the cable tie tension at which the tie tail is cut off) so as to produce clean cuts with no cutting protrusions.

Cut-Off Mechanism

The cut-off mechanism 500 cuts or severs the engaged cable tie tail when a predetermined tension is reached. As illustrated in the simplified assembled tool mechanism shown in FIG. 13(a), the cut-off mechanism 500 is directly coupled with the trigger mechanism 200 (via inner trigger link 204) and the adjustable biasing mechanism 600 (via fulcrumed lever link 602 about third fulcrum pin 606), as well as, operably engaged with the locking mechanism 400 (via cam link 538).

Referring now to FIG. 13(b), the cut-off mechanism 500 is arranged within the barrel portion 104 of the housing 102 below and substantially parallel to the pawl link 302 and comprises a cutting lever 502 having a blade member 504 on its distal cutting lever end 506 and an engagement surface portion 508 on its proximal cutting lever end 510. The cutting lever 502 is pivotally coupled to the housing 102 via fulcrum pin 512, so as to allow rotation of the cutting lever 502 about the fulcrum pin 512 relative to the housing 102, as well as, relative to the reciprocatingly movable pawl link 302. As shown in FIGS. 4 and 5, the blade member 504 is arranged forward of the distal housing end portion 106 or front cover portion 114 mounted to the tension mechanism 300 (i.e. forward of the gripping pawl 310 and backing plate 314) and is operably encased by a blade guard 526 (see FIG. 15).

The cutting lever 502 is configured to move between an upper position, i.e. blade member 504 is cuttingly engaged with the tie tail, and a lower position, blade member 504 is disengaged from the tie tail. When the blade member 504 is in the lower position, the finger member 540 of the cam link 538 is supportingly engaging the distal lever end 410 of the locking lever 402 of the locking mechanism 400, i.e. pushing the distal lever end 410 of the locking lever 402 into its upper position.

A cutting linkage 514 is coupled to the proximal cutting lever end 510 so as to operably link the cutting lever 502 with the inner trigger link 204 of the trigger mechanism 200. In particular, the cutting linkage 514 comprises a pivot link 516 (i.e. two parallel pivot link members 516a,b) directly and pivotally coupled to the proximal cutting lever end 510 via a pivot pin 520, and a sliding link 518 (comprised of two parallel sliding link members) operably coupled between the pivot link 516 (via pivot pin 522) and the inner trigger link 204. The sliding link 518 is slidingly retained by third cam surfaces or guides 122a,b provided within the housing 102 via cam followers 524a,b, so as to only allow reciprocating linear movement of the sliding link 518 between a forward (distal) position and a rearward (proximal) position. Here, the sliding link 518 is provided with a pin 522 (comprising cam follower 524a) and 520 (comprising cam follower 524b) each one configured to slidingly engage with the complementary cam guides 122a,b of the housing 102. Further, pivot pin 522 comprises a centre portion between respective sliding link members that also acts as cam follower for the cam link 538.

FIG. 14 illustrates the function in combination with the locking mechanism 400, where a force acting on the sliding link 518 (white arrow) is provided by the inner trigger link 204 (not shown). FIG. 14(a) illustrates the cutting lever 502 in its lower position (i.e. blade member 504 is disengaged) with no force acting on the sliding link 518. When the predetermined maximum tension is reached with the handle lever 224 pushed back against the housing 102, any additional pull on the trigger lever 202 will rotatingly push the inner trigger link 204 and sliding link 518 forward (white arrow). As the pivot pin 522 of pivot link 516 is forced linearly forward over the cam surface threshold 542 of cam link 538 (with an initial higher resistance at opening flank and a reduced resistance on the closing flank), allowing the finger member 540 to rotate away and the distal lever end 410 of the locking lever 402 to pivot down, the pivot link 516 can only rotatingly move away about the pivot pin 522, thus, moving the proximal cutting lever end 510 downward and the blade member 504 upward. Thus, the force acting on the sliding link 518 is translated into a rotational movement of the cutting lever 502 about its fulcrum pin 512.

Referring now to FIG. 17, a blade guard 526 is illustrated in a detailed close up view. The blade guard 526 is configured to attach to the distal housing end portion 106 operably enclose the blade 504. In particular, the blade guard 526 comprises a front wall 530 having an outer front surface 532 and an inner front surface 534. The inner front surface 534 is shaped so as to provide a cam guide for the blade member 504, i.e. the inner front surface 534 is inclined at a predetermined angle relative to the outer front surface 532, such as, for example, an angle between 2° (degrees) and 5°, and preferably and angle of about 3.7° (degrees). Thus, during pivotal movement of the cutting lever 502, the blade member 504 slidingly follows the cam guide provided by the inclined inner front surface 534 of the blade guard 526. This “forces” the blade 504 to cut through the tie tail at a predetermined angle (e.g. 3.7°) so as to avoid, or at least minimise, the formation of potentially harmful burrs. Furthermore, the front wall 530 of the blade guard 526 has an aperture 536 for the cable tie to enter and engage with the tension mechanism 300 of the tool 100. In one example, the outer front surface 532 of the front wall 530 may be concavely shaped around the aperture so as to further improve the cutting characteristics of the tool 100. The concave shaped region of the front wall 530 may provide for a “deeper” cut, so as to avoid or at least minimise any protruding ends at the cable tie head after cutting the cable tie tail.

In summary, the cut-off mechanism 500 provides a simplified and robust assembly for very precise and repeatable cutting action of the blade member 504.

FIGS. 20 and 21 show detailed close up views of the cam link 538 coupled to the link lever 602 and engaged with the cam follower 522 (pivot pin) of sliding link 518. The cam link 538 is rotatably coupled within the hosing 102 via a cam link pivot pin 544 (e.g. via suitable mounts in the housing), allowing the cam link 538 to pivot about the cam link pivot pin 544 between an upward position, stoppingly engaging the locking lever 402, and a downward position, disengaged from the locking lever 402. An elongated aperture 546 of the cam link 538 is operably coupled with a lever link pin 634. The cam follower 522 of the sliding link 518 is operably engaged on a cam surface 548 of the cam link 538. A shown in particular in FIG. 21, the cam surface 548 includes a transition portion or cam surface threshold 542. The cam surface threshold is provided by a predetermined contour or surface profile having an opening flank 550 and a closing flank 552. The opening flank 550 is shaped so as to provide a gradual increase in resistance for the cam follower 522 moving toward the finger member 540. The closing flank is shaped so as to gradually reduce the resistance for the cam follower 522 moving towards the finger member 540. Therefore, the cam surface threshold 542 provides a user perceived minimal effort when squeezing the trigger lever 202, i.e. after the initial increased effort to overcome the opening flank 550, the force required for the closing flank 552 is significantly reduced. Also, the cam link 538 is arranged (i.e. coupled with) the cam follower 522 and lever link 602 so as to always have a positive bias from coil spring 608 of the biasing mechanism 600 (i.e. the cam link always “feels” the force of the coil spring 608). This arrangement provides for a smoother function and feel.

Adjustable Biasing Mechanism

The adjustable biasing mechanism 600 provides for a selectively adjustable biasing force setting the maximum tension applied to the cable tie at which the tie tail section is cut off. The adjustable biasing mechanism 600 is operably coupled with the cut-off mechanism 500 and the trigger mechanism 200 via a fulcrumed lever link 602 and operably incorporates the rack member 414 of the locking mechanism 400.

Referring now to FIG. 15, the adjustable biasing mechanism 600 includes a spring housing 610 having a coupling member 604 extending away from a distal end 616 of the spring housing 610 (i.e. towards the distal cutting lever end 506) and is adapted to receive a spring member such as a coil spring 608, as well as, a plunger member 614. The plunger member 614 is slidably movable within the housing 610 so as to compress the torsion spring 608 when moving towards the distal end 616 of the housing 610 and expand the torsion spring 608 when moving back towards a proximal end 618 of the housing 610. Furthermore, the plunger member 614 comprises one radially outwards extending lateral protrusions 620 that is adapted to slide into a respective guide groove 622 (or longitudinal aperture) formed within the spring housing 610 so as to prevent rotation of the plunger member 614, during use. A lead screw mechanism 624 is operably coupled with the plunger member 614 and mounted within the housing 102 such that rotation of a proximal end portion 626 of the lead screw mechanism 624 is translated into linear axial movement of plunger member 614. The rotation of the proximal end portion 626 may be provided by the user via an adjustment knob 630 coupled to the proximal end portion 626 of the lead screw mechanism 624. Thus, when the user rotates the adjustment knob 630, the lead screw mechanism 624 moves the plunger member 614 distal or proximal within the spring housing 610 to either compress or expand the coil spring 608 within the spring housing 610. Lead screw mechanisms, such as the one illustrated, are well known in the art and are not described in any more detail. Also, any suitable variation or embodiment of such a mechanism (i.e. translating rotation into linear axial movement) may be used within the scope of this disclosure.

An indexing mechanism comprising an index member 640 and two ball bearings 642, provided on the rack member 414 and arranged laterally opposite to each other, may be provided to improve the feedback when rotating the adjustment knob 630 (tactile feedback when feeling the ball bearings move over the indexed space, or audible feedback from the ball bearings moving over the index member 640).

The position of the plunger member 614 within its housing 610 determines the precompression of the torsion spring 608 and thus controls the biasing force provided by the adjustable biasing mechanism 600 via the fulcrumed lever link 602.

Additionally (i.e. optionally), a gear mechanism 1634 (see FIG. 16(b), such as a spin or torque multiplier, may be operably coupled between the adjustment knob 630 and the proximal end portion 626 of the lead screw mechanism 624. For example, the spin multiplier 634 is adapted to multiply relative rotational displacement of one axis end onto the other axis end so that a relatively small rotational movement of the adjustment knob 630 translates into a greater linear axial movement of the lead screw mechanism 624. Thus, standard threads can be used for the lead screw mechanism 624 while providing a user-friendly knob rotation during adjustment. For example, an epicyclic gear train or planetary gear set may be used for the spin multiplier 634 so as to align the rotational axes of the adjustment knob 630 and the lead screw mechanism 624.

It is understood by the person skilled in the art, that the adjustable biasing mechanism 600 of the present disclosure provides for a simplified and more robust assembly having a reduced number of components. Moreover, the use of a spin multiplier 634, such as, for example, an epicyclic gear, allows for a more user-friendly number of rotation of the adjustment knob 630 required to adjust the tension, as well as, an intuitive choice of the direction of rotation of the adjustment knob 630, i.e. a clockwise rotation for increasing precompression (i.e. increase cut-off tension of the tie tail) and an anti-clockwise rotation for decreasing precompression (i.e. reduce cut-off tension of the tie tail).

FIG. 16(a) shows the assembled adjustable biasing mechanism 600 including the rack member 414, but without any of the other mechanisms groups. FIG. 16(b) is an alternative assembled adjustable biasing mechanism 1600, including a rack member, but without any of the other mechanisms groups.

FIG. 18 illustrates a close up view of (a) the rack member 414 with a plurality of triangular teeth 424, (b) the stop member 404 with a plurality of triangular teeth 426 that are complementarily shaped to the triangular teeth 424 of the rack member 414, and (c) the teeth 426 of the stop member 404 are lockingly engaged with the teeth 424 (and spaces) of the rack member 414. Respective teeth 424 and 426 have been modified to allow a “well wedged” engagement. In particular, each one of the plurality of triangular teeth 424 and 426 comprise a vertical front surface 428, 430 and respective inclined back surface 432, 434, arranged such that the vertical front surfaces 428, 430 contactingly engage when in the locked position. Preferably, the angle between the front surface 430 of the teeth 426 of the stop member 404 when in the lower unlocked position and a vertical plane (perpendicular to the longitudinal axis 110) is in the region of 7° (degrees), however, any other suitable angle may be used to optimise engagement and disengagement between rack member 414 and stop member 404.

Operation of an Embodiment of the Cable Tie Tool 100

The operation of the cable tie tool 100 is now described with reference to FIGS. 4 and 5 summarising the individual functions described for each one of the mechanism 200, 300, 400, 500 and 600.

A user may first set a desired cut-off tension for the cable tie looped around the components by rotating the adjustment knob 630 and changing the precompression of the torsion spring 608 within the spring housing 610. The precompression of the spring 608 will set a predetermined bias applied via the fulcrumed lever link 602 and coupling member 604 of the spring housing 610.

A tie tail of a looped cable tie is then inserted through the blade guard aperture 536 and distal housing cover 114 and into engagement with the gripping pawl 310 and backing plate 314. When the user squeezes the trigger lever 202, the pawl link 302 moves back “releasing” the gripping pawl 310 engagement with the engagement portion 120 allowing the gripping pawl 310 to slide up and forward and into gripping engagement with the tie tail. The engaged gripping pawl 310 and tie tail are then pulled back by the handle lever 224 via the pawl link 302, thus, pulling the tie tail backwards towards the proximal housing end portion 108 and closing the cable tie loop around the components. Upon release of the trigger lever 202, the biased handle lever 224 pushes the trigger lever 202 back into its starting position, ready for the user to squeeze the trigger lever 202 again to further tighten the loop until the tension in the tie tail gradually increases.

When the pre-set tension within the tie tail is reached, any additional force on the trigger lever 202 is translated into a forward rotation of the inner trigger link 204 (via handle lever 224 and short link 230). The forward movement of the inner trigger link 204 pushes the sliding link 518 forward and rotates the pivot link 516 about its pivot pin 522, subsequently rotating the proximal cutting lever end 510 downward about fulcrum pin 512. At the same time, the cam follower provided by pivot pin 522 moves over the cam surface threshold 542 pushing the lever link 602 against the biasing force provide by the coil spring 608, thus, rotating the cam link 538 and finger member 540 out of engagement with the locking lever 402. This movement will remove the support for the distal lever end 410 of the locking lever 402, which is now “free” to be rotated about its fulcrum pin 412 effected by the coil spring 420 that is embedded in the lever support member 418 therefore moving the distal lever end 410 down and the stop member 404 upward into locking engagement with the rack member 414. The tension mechanism 300 is now locked into position while the blade member 504 is moved upward (along inclined inner front wall surface 534 of the blade guard 526) to cut through the tie tail.

The sudden release of the tension in the cut tie tail removes the force counteracting the spring biased coupling member 604 and lever link 602, such that the lever link 602 rotates back (pushed up by the cutting lever spring 528), moving the sliding link 518 back allowing the cam link to rotate back and the pivot link 516 up. The finger member 540 pushes the distal lever end 410 back up and rotates the stop member 404 of the locking lever 402 out of engagement with the rack member 414. The tension mechanism 300 and pawl link 302 are now free to reciprocatingly move within the barrel portion 104 so that the gripping pawl 310 can be moved backward when contactingly engaging with the engaging portion 120 of the distal housing end portion 106 and disengage from the cut tie tail. The movements of each one of the involved components is timely coordinated such that locking and cutting is practically simultaneous, therefore, preventing any sudden pull-back of the gripping pawl 310 and pawl link 302 and allowing a very clean cut through the tie tail before the pawl link 302 is released again.

It will be appreciated by persons skilled in the art that the above embodiment(s) have been described by way of example only and not in any limitative sense, and that various alterations and modifications are possible without departing from the scope of the invention as defined by the appended claims. Various modifications to the detailed designs as described above are possible, for example, variations may exist in shape, size, arrangement (i.e. a single unitary components or two separate components), assembly or the like.

APPENDIX

According to an aspect, there is provided a tool for tensioning and severing an elongate cable tie having a tie head portion and a tie tail portion, said tool comprising: a pistol-shaped housing, having a barrel portion extending between a distal housing end portion and a proximal housing end portion along a longitudinal axis, and a handle portion extending away from said barrel portion in a direction different to said longitudinal axis; a trigger mechanism, comprising an elongate trigger member extending away from said barrel portion operably forward of said handle portion and configured to move toward and away from said handle portion; a tension mechanism, comprising a pawl link provided slidably reciprocatingly within said barrel portion along said longitudinal axis and operably coupled to said trigger mechanism, configured to grippingly engage the cable tie and apply tension to the tie tail when moving said elongate trigger member toward said handle portion, during use; a locking mechanism, provided within said barrel portion and operably coupled with said tension mechanism, configured to stop operation of and lock said tension mechanism at a predetermined tension of the tie tail; a cut-off mechanism, provided within said barrel portion and operably coupled with said trigger mechanism and said locking mechanism, configured to cut the tie tail when said locking mechanism is lockingly actuated, and wherein said pawl link comprises at least one guide aperture at a distal end portion configured to slidably receive and retain a corresponding guide member of a gripping pawl, so as to allow sliding movement of said gripping pawl relative to said pawl link between a first position and a second position, towards the cable tie tail, during use, in a direction intersecting said longitudinal axis, and wherein said gripping pawl is resiliently biased towards said second position.

This provides the advantage that the guide aperture can be defined so as to optimise the path of the gripping pawl relative to the pawl link, thus, allowing a maximised contact engagement between the gripping pawl and the cable tie tail, during use. In addition, using a biased sliding movement of the gripping pawl allows for a greater range of tie tail thicknesses that can be accommodated (i.e. sufficiently gripped) with the tool.

Preferably, said second position is distal to said first position.

Advantageously, said pawl link comprises two substantially matching parallelly arranged arms extending along said longitudinal axis, each one provided with a respective one of said at least one guide aperture at said distal end portion, configured to operably receive and slidingly retain said gripping pawl, therebetween. Preferably, two guide apertures may be provided at said distal end portion of each one of said two substantially matching parallelly arranged arms.

Advantageously, said pawl link further comprises a backing plate at said distal end portion configured to cooperate with said gripping pawl so as to operably engage the cable tie, during use. Preferably, said backing plate is provided on an upper surface of said pawl link facing in a direction opposite said handle portion.

Advantageously, said second position is towards said backing plate.

Advantageously, said at least one guide aperture defines a predetermined cam profile for said guide member configured to maximise contact engagement between said gripping pawl, the tie tail and said backing plate, during use.

Advantageously, said gripping pawl is resiliently biased towards said second position via a spring element operably coupled between said gripping pawl and said pawl link.

Advantageously, said at least one guide member extends from a side portion of said gripping pawl in a direction perpendicular to said longitudinal axis.

Advantageously, said gripping pawl is further adapted to contactingly engage with an engagement portion of said distal housing end portion so as to push said gripping pawl towards said first position by a predetermined distance when said pawl link is in a starting position.

According to another aspect, there is provided a tool for tensioning and severing an elongate cable tie having a tie head portion and a tie tail portion, said tool comprising: a pistol-shaped housing, having a barrel portion extending between a distal housing end portion and a proximal housing end portion along a longitudinal axis and a handle portion extending away from said barrel portion in a direction different to said longitudinal axis; a trigger mechanism, comprising an elongate trigger member extending away from said barrel portion operably forward of said handle portion and configured to move toward and away from said handle portion; a tension mechanism, comprising a pawl link provided slidably reciprocatingly within said barrel portion along said longitudinal axis and operably coupled to said trigger mechanism, configured to grippingly engage the cable tie and apply tension to the tie tail when moving said elongate trigger member toward said handle portion, during use; a locking mechanism, provided within said barrel portion and operably coupled with said tension mechanism, configured to stop operation of and lock said tension mechanism at a predetermined tension of the tie tail, during use; a cut-off mechanism, provided within said barrel portion and operably coupled with said trigger mechanism and said locking mechanism, configured to cut the tie tail when said locking mechanism is lockingly actuated, and wherein said locking mechanism further comprises: a locking lever, having a stop member at a proximal lever end and a contact portion at a distal lever end, said locking lever is arranged parallelly adjacent to said pawl link and pivotally coupled to a first fulcrum pin of said pawl link, so as to allow rotation of said locking lever about said fulcrum pin relative to said pawl link between an unlocked position and a locked position; a rack member, mounted immovably relative to said housing, adapted to lockingly engage with said stop member when said locking lever is in said locked position; wherein said contact portion is arranged so as to operably engage with said cut-off mechanism so as to be moved between an upper position, retaining said locking lever in said unlocked position, and a lower position, moving said locking lever into said locked position.

This provides the advantage of obtaining a more stable and repetitive tension in the cable tie tail, allowing for cleaner and closer tail cuts, i.e. minimising or even avoiding any protruding edges from the tie head portion.

Advantageously, said contact portion of said locking lever is arranged so as to contactingly engage with a cutting lever of said cut-off mechanism.

Preferably, said locking lever is biased towards said locked position.

Advantageously, said locking mechanism further comprises a lever support member mounted to said proximal end portion of said pawl link and configured to supportingly engage with said proximal lever end when in said unlocked position.

Advantageously, said lever support member comprises a first biasing member configured to resiliently bias said locking lever towards said locked position. Preferably, said first biasing member is a coil spring integrated with a support surface of said lever support member.

Advantageously, said stop member comprises at least one tooth-shaped protrusion extending from said proximal lever end towards said rack member. Preferably, said stop member comprises a plurality of tooth-shaped protrusions.

Advantageously, said rack member comprises a plurality of equidistantly spaced recesses on a bottom surface, each one configured to interlockingly receive said stop member.

According to another aspect, there is provided a tool for tensioning and severing an elongate cable tie having a tie head portion and a tie tail portion, said tool comprising: a pistol-shaped housing, having a barrel portion extending between a distal housing end portion and a proximal housing end portion along a longitudinal axis and a handle portion extending away from said barrel portion in a direction different to said longitudinal axis; a trigger mechanism, comprising an elongate trigger member extending away from said barrel portion operably forward of said handle portion and configured to move toward and away from said handle portion; a tension mechanism, comprising a pawl link provided slidably reciprocatingly within said barrel portion along said longitudinal axis and operably coupled to said trigger mechanism, configured to grippingly engage the cable tie and apply tension to the tie tail when moving said elongate trigger member toward said handle portion, during use; a locking mechanism, provided within said barrel portion and operably coupled with said tension mechanism, configured to stop operation of and lock said tension mechanism at a predetermined tension of the tie tail; a cut-off mechanism, provided within said barrel portion and operably coupled with said trigger mechanism and said locking mechanism, configured to cut the tie tail when said locking mechanism is lockingly actuated, said cut-off mechanism comprising: a cutting lever, having a blade member at a distal cutting lever end, arranged parallelly below said pawl link and pivotally coupled at a second fulcrum pin of said housing, so as to allow rotation of said cutting lever about said second fulcrum pin relative to said housing between an upper position, cuttingly engaging with the cable tie, and a lower position, disengaged from the cable tie; cutting linkage, operably coupling a proximal cutting lever end with said trigger mechanism, so as to rotate said cutting lever between said upper position and said lower position at a predetermined condition during actuation of said trigger mechanism.

Advantageously, said proximal cutting lever end comprises a protrusion extending towards said locking mechanism.

Advantageously, said sliding link is operably coupled within said housing so as to allow sliding movement in a direction parallel to said longitudinal axis.

Advantageously, said pivot link is biased so as to move said cutting lever towards said lower position.

Advantageously, said predetermined condition is a predetermined tension of the tie tail transmitted via said inner trigger link, during use.

Advantageously, said tool further comprises an adjustable biasing mechanism operably coupled to said inner trigger link via said cutting linkage, configured to provide an adjustable threshold force defining said predetermined tension of the tie tail during use.

According to another aspect, there is provided a tool for tensioning and severing an elongate cable tie having a tie head portion and a tie tail portion, said tool comprising: a pistol-shaped housing, having a barrel portion extending between a distal housing end portion and a proximal housing end portion along a longitudinal axis and a handle portion extending away from said barrel portion in a direction different to said longitudinal axis; a trigger mechanism, comprising an elongate trigger member extending away from said barrel portion operably forward of said handle portion and configured to move toward and away from said handle portion; a tension mechanism, comprising a pawl link provided slidably reciprocatingly within said barrel portion along said longitudinal axis and operably coupled to said trigger mechanism, configured to grippingly engage the cable tie and apply tension to the tie tail when moving said elongate trigger member toward said handle portion, during use; a locking mechanism, provided within said barrel portion and operably coupled with said tension mechanism, configured to stop operation of and lock said tension mechanism at a predetermined tension of the tie tail; a cut-off mechanism, provided within said barrel portion and operably coupled with said trigger mechanism and said locking mechanism, configured to cut the tie tail when said locking mechanism lockingly actuated, and an adjustable biasing mechanism, comprising a second biasing member provided within said barrel portion, adapted to provide a biasing load to any one of said trigger mechanism, said tension mechanism and said cut-off mechanism.

Advantageously, said biasing mechanism comprises a lever link configured to operably couple said second biasing member with any one of said trigger mechanism, said tension mechanism and said cut-off mechanism.

Advantageously, said lever link is pivotably mounted to a third fulcrum pin of said housing, so as to translate a linear movement from a sliding link of a cutting linkage of said cut-off mechanism into a rotational movement of said lever link about said third fulcrum pin.

Advantageously, said second biasing member is operably coupled with said lever link so as to biasingly counteract rotational movement of said lever link about said third fulcrum pin.

Advantageously, said tool further comprises a preload control mechanism configured to selectively change said biasing load provided by said second biasing member in predetermined steps.

Advantageously, said preload control mechanism comprises a lead screw mechanism operably coupled between an adjustment knob and said second biasing member and adapted to convert a rotational movement of said adjustment knob into a change of said biasing load provided by said second biasing member.

This provides the advantage of allowing adjustment of the maximum tension applied to the tie tail at which the cutting mechanism is actuated, and the tie tail is cut. Thus, the user has the option to apply different cable tie pressures to the bundled components.

Additionally, said preload control mechanism may comprise a gear mechanism operably coupled between said adjustment knob and said lead screw mechanism, configured to provide a predetermined transmission ratio between rotational movement of said adjustment knob and a resulting rotational movement of a threaded shaft of said lead screw mechanism.

Preferably, said a gear mechanism is a spin multiplier.

Reference numerals list:

100
Tool
236
pivot axis (short link forward)

102
housing
238
pivot axis (short link rearward)

104
barrel portion
240a, b
trigger bearings

106
distal housing end portion
242
pivot axis (handle lever)

108
proximal housing end portion
244
elongate aperture

110
longitudinal axis
246
biasing member (torsion

spring)

112
handle portion
300
tension mechanism

114
front cover portion
302
pawl link

116
first cam guide
302a, b
pawl links (L, R)

118
second cam guide
304a, b
pairs of guide apertures (L, R)

120
pawl engagement portion
306
distal end portion (Pawl link)

122a, b
third cam guides
308a, b
pairs of guide members

124
stopping plate
310
gripping pawl

200
trigger mechanism
311
pivotable gripping pawl

202
elongate trigger lever
314
backing plate

204
inner trigger link
316a
Coils spring

206
trigger housing portion
316b
Spring block

208
pivot axis (lever)
317
torsion spring

210a
lever side face (L)
318a, b
link bearings

210b
lever side face (R)
320
proximal end portion

212
lever front face
322
bearing pin

214
lever recess
326
protrusion (gripping pawl)

216
lower link end
400
locking mechanism

218
pivot axis (inner link)
402
locking lever

220
upper link end
404
stop member

222
elongate aperture (oval)
406
proximal lever end

224
handle lever
408
contact surface

226
lower lever end
410
distal lever end

227
proximal (upper) end (trigger
412
first fulcrum pin

lever)

228
upper lever end
414
rack member

230
short link
418
lever support member

232
forward end
420
first biasing member (coil

spring)

234
rearward end
546
elongated slot

424
triangular teeth(rack)
548
cam surface

426
triangular teeth (stop member)
422
Support surface

428
vertical front surface (rack)
550
opening flank

430
vertical front surface (stop
552
closing flank

member)

432
inclined back surface (rack)
600
adjustable biasing mechanism

434
inclined back surface (stop
602
fulcrumed lever link

member)

500
cut-off mechanism
604
coupling member

502
cutting lever
605
grooves

504
blade member
606
third fulcrum pin

506
distal cutting lever end
608
second biasing member (spring)

508
Engagement surface portion
610
spring housing

510
proximal cutting lever end
614
plunger member

512
second fulcrum pin
616
Distal end portion (spring

housing)

514
cutting linkage
618
proximal end portion (spring

housing)

516a, b
pivot link
620
protrusion

518
sliding link
622
guide groove

520
pivot pin (pivot link)/axis
624
lead screw mechanism

522
pivot pin (sliding link)/axis
626
proximal end portion

524a, b
first cam followers
628
distal end portion

526
blade guard
630
adjustment knob

528
cutting lever spring
634
lever link pin

530
front wall (blade guard)
636
biased locking switch

532
outer front surface (blade
640
index member

guard)

534
inner front surface (blade
642
ball bearings

guard)

536
aperture (blade guard)
1600
alternative adjustable biasing

mechanism

538
cam link
1624
lead screw mechanism

540
finger member
1630
adjustment knob

542
cam surface threshold
1634
gear mechanism

544
cam link pivot pin

Number	Date	Country	Kind
22208441.0	Nov 2022	EP	regional
22211262.5	Dec 2022	EP	regional

CABLE TIE TENSIONING AND CUT-OFF TOOL

Information

Publication Number

Date Filed

Date Published

Inventors

Original Assignees

CPC

International Classifications

Abstract

Description

Claims

Priority Claims (2)