Embodiments of the present invention relate to a winding assembly with a mesh drive linkage. In particular, the winding assembly is a pallet lid winding assembly with a mesh drive linkage.
It is known to load goods on pallets. Lids can be mounted on the loads. Such lids are provided with straps to tighten the lid against the load when the ends of the straps as secured to the pallet. The lids include tightening mechanisms, operated by levers, to tighten the strap, thereby pulling the lid against the load. In some situations, using the tightening mechanisms by operating the levers can be time consuming. For example, the lever may need to be turned many times to ratchet the straps tight.
According to various, but not necessarily all, embodiments of the invention there is provided a winding assembly comprising:
An advantage of the use of a meshing drive linkage is the prevention of slippage in the drive linkage and more precise control of the tensioner. The total mechanical work done by the interface is consistent and predictable, resulting in a predictable amount of tension so that the tensioning line is neither too tight nor too loose. The user no longer has to judge the correct amount of tension.
The mesh drive linkage of the winding assembly may comprise a driver actuatable by the lever, and the tensioner may comprise a drive input directly or indirectly coupled to the driver via meshing, and actuated by the driver.
The driver and/or the tensioner drive input may be a mesh drive such as a sprocket or a gear. The sprocket(s) may connect to a perforated or indented drive loop such as a ribbed belt or chain. The ribbed belt may comprise transverse ribs.
Alternatively, the driver and/or the tensioner drive input comprises a gear, for example, the driver gear may mesh directly with the tensioner drive input gear.
The driver gear may comprise a worm drive and the tensioner drive input gear may comprise a worm wheel. The worm drive and worm wheel may directly mesh.
Alternatively, the driver gear may comprise a bevel gear and the tensioner drive input gear may comprise a bevel gear. The bevel gears may directly mesh.
In some examples, the mesh drive linkage can be driven in reverse to release the tensioner. Alternatively, if the mesh drive linkage comprises gears, the driver gear and/or the tensioner drive input gear may be movable out of meshing with each other to release the tensioner. The driver gear may slide perpendicular to its axis of rotation and/or the tensioner drive input gear may slide perpendicular to its axis of rotation. The winding assembly may comprise a tactile user control, such as a button, connected to a slider or other mechanism to cause the de-meshing.
The mesh drive linkage may provide an interface: tensioner gear ratio of greater than 5:1 or greater than 10:1 or greater than 15:1. The angular distance from a home position of the tensioner to a tensioning position of the tensioner may be a reflex angle, such as approximately 300 degrees. In an example implementation, 18 turns of the interface turns the tensioner by the required reflex angle.
The interface may be rotatable about an input axis of rotation extending through the fulcrum body. The input axis may be an upwards axis such as a vertical axis. Therefore, the interface may rotate laterally.
An advantage of the direction change is that the winding assembly has a low vertical height, because the interface rotates laterally. Therefore, the winding assembly is suitable for use as a pallet lid winding assembly.
The tensioner may be rotatable about a tensioner axis of rotation different from the input axis of rotation. The tensioner axis may be a lateral axis. The tensioner axis may be perpendicular to the input axis. The mesh drive linkage of the winding assembly may connect the input axis of rotation to the tensioner axis of rotation. For example, if a drive loop (e.g., belt) is used, the drive loop may be twisted. For example, the drive loop may comprise a quarter-twist. If a gear drive linkage is used instead, the driver may be a bevel gear or worm drive to change the direction of rotation.
The interface may comprise a recess configured to receive a tool, which may be a drive key. The recess may be a polygonal recess. The drive key may be a polygonal drive key, having a polygonal end profile. The tool may be an electric tool capable of rotating the drive key. The recess may be a hexagonal recess or another suitable shape, such as star-shaped. The drive key may be a hex drive key, a star shaped drive key, or any other suitable drive key.
An advantage is enabling full or partial automation of tensioning.
If the interface is a recess for receiving a drive key, over-tensioning may be prevented by providing the tensioner or the mesh drive linkage with an end stop. The end stop may collide with a portion of the winding assembly when the tensioner reaches its tensioning position, preventing further tensioning.
Instead of a recess, or in addition to a recess, the interface may comprise a lever. The lever may comprise a fulcrum body and an elongate handle extending from the fulcrum body. A lever is suitable for hand actuation.
If the interface is a lever, over-tensioning may be prevented by providing the winding assembly with a handle retainer configured to engage with the elongate handle of the lever following actuation of the lever in a first, tensioning direction, to prevent movement of the elongate handle of the lever in a second, opposite direction.
The lever has a stroke length associated therewith, wherein actuation of the lever by a single stroke length in a tensioning direction may actuate the tensioner from a home position of the tensioner to a tensioning position of the tensioner. When the elongate handle of the lever is engaged with the handle retainer the at the end of the single tensioning stroke, the tensioner is at the tensioning position.
An advantage is that the user is not able to over-tension or otherwise misuse the winding assembly. This is because the handle retainer and/or single-stroke operation provide clear feedback that the user has done all that needs to be done, to tension the tensioning line.
The handle retainer may comprise a catch to automatically (i.e., without user intervention) engage and hold the elongate handle of the lever when the elongate handle of the lever is actuated into the catch. For example, the handle retainer may comprise a snap fit catch.
An advantage of the catch-type handle retainer is further feedback that the user has done what needs to be done to tension the tensioning line, without the user needing to remember to manually engage the handle retainer. It would be understood that a manual latch could be used instead.
Alternatively, the handle retainer is replaced with a downstream retainer, configured to engage following actuation of the lever in the first, tensioning direction, to prevent movement of the lever in the second, opposite direction, wherein if the retainer is a handle retainer the engagement is with the elongate handle of the lever, and wherein if the retainer is a downstream retainer the engagement is downstream of the elongate handle of the lever.
The mesh drive linkage may comprise injection moulded parts. They may be injection moulded plastics. The injection moulding may also form the recess (e.g., hex key recess) in one of the mesh drive linkage parts. In an example implementation, the driver gear comprises a worm drive, an end of the worm drive comprising the interface such as the recess. An advantage is optimisation for manufacture.
The mesh drive linkage may comprise drop-in parts. The winding assembly may comprise a drop-in cavity arrangement sized to support one or more of the parts in an operational orientation when the parts are lowered in to the drop-in cavity arrangement during manufacture.
The whole tensioner (including its tensioner drive input) may be a drop-in part. The drop-in cavity arrangement may comprise bearings and a tensioner-receiving channel therebetween, onto which the tensioner can be lowered. The drop-in cavity arrangement may comprise a cylindrical recess into which a worm drive can be lowered.
The tensioner may be configured to receive the tensioning line therethrough. The tensioner may be rotatable by the interface via the mesh drive linkage. The rotation of the tensioner may wind the tensioning line around the tensioner. In an example, the tensioner may be slotted, to receive the tensioning line therethrough. The tensioner may be a slotted spindle. The tensioning line may comprise a strap.
The winding assembly may comprise a drum axle configured to receive a drum from which the tensioning line can be unwound and to which the tensioning line can be wound. The drum axle may comprise an urger, such as a spiral spring, to bias a drum fitted to the drum axle in a winding direction. The urger may bias the tensioner from a tensioning position of the tensioner towards a home position of the tensioner. Unintended back-rotation is prevented by the handle retainer if the interface comprises a lever, or if the interface comprises a recess, is prevented by a combination of friction and the high gear reduction of the mesh drive linkage.
According to various, but not necessarily all, embodiments of the invention there is provided a winding assembly comprising:
An advantage of the winding mechanism is the prevention of slippage, similar to the mesh drive linkage. The prevention of slippage advantageously ensures that the single stroke of the lever consistently results the required amount of tension.
The drive linkage may comprise a lever-actuatable driver. The tensioner may comprise a tensioner drive input coupled to the driver by a transmission line such as a cable.
An angular distance from a home position of the tensioner to a tensioning position of the tensioner may be a reflex angle, such as approximately 300 degrees.
The interface may be rotatable about an input axis of rotation extending through a fulcrum body. The input axis may be an upwards axis. The tensioner may be rotatable about a tensioner axis of rotation different from the input axis of rotation. The tensioner axis of rotation may be a lateral axis.
The lever may comprise a fulcrum body and an elongate handle extending from the fulcrum body. The lever may be suitable for hand actuation.
The winding assembly may comprise a retainer configured to be engaged following actuation of the lever in a first, tensioning direction, to prevent movement of the lever in a second, opposite direction, wherein the retainer is in the form of a handle retainer or downstream retainer, configured to engage following actuation of the lever in the first, tensioning direction, to prevent movement of the lever in the second, opposite direction, wherein if the retainer is a handle retainer the engagement is with the elongate handle of the lever, and wherein if the retainer is a downstream retainer the engagement is downstream of the elongate handle of the lever.
The drive linkage may comprise injection moulded parts and/or drop-in parts.
The tensioner may be configured to receive the tensioning line therethrough. The tensioner may be rotatable by the interface via the mesh drive linkage. The rotation of the tensioner may wind the tensioning line around the tensioner. The tensioner may comprise a slotted spindle. The tensioning line may comprise a strap.
The winding assembly may comprise a drum axle configured to receive a drum from which the tensioning line can be unwound and to which the tensioning line can be wound. The drum axle may comprise an urger to bias the drum fitted to the drum axle in a winding direction.
For a better understanding of various examples of embodiments of the present invention reference will now be made by way of example only to the accompanying drawings in which:
The body 4 comprises an upper portion 7 shown formed by a plurality of plastics mouldings 8, but which could be formed as a single moulding. The body 4 further includes a lower portion 9 formed by a main plastics moulding.
The lid 1 includes four tensioning lines in the form of straps 10. Each tensioning line 10 is movable between a retracted condition within the upper portion 7, and an extended condition in which the tensioning line 10 extends from the upper portion 7. Each tensioning line 10 is provided at a respective side of the lid 1.
Each tensioning line 10 has a distal end to which an anchor 14 is attached. An anchor 14 can comprise a hook, loop or any other suitable attacher. In the extended condition of the tensioning lines 10, the anchors 14 can be secured to the pallet 3. As shown in
When the anchors 14 are secured to the pallet 3, as shown in
Only two of the tensioning lines 10 are visible in
The winding assembly 16 comprises a drum axle 13 configured to receive the drum 12 from which the tensioning line 10 can be unwound when in use, and to which the tensioning line 10 can be re-wound when not in use.
The drum axle 13 may comprise an urger (hidden from view), such as a spring connected at one end to the drum axle 13 and at the other end to the drum 12. The urger rotatably biases the drum 12 in a winding direction to wind the tensioning line 10 on the drum 12, to move the tensioning line 10 to its retracted condition. For example, the urger may comprise a spiral spring.
The tensioning line 10 extends away from the drum 12 along a tensioning line channel 22 and through a tensioning line opening 24 in the lateral exterior of the winding assembly 16. The tensioning line channel 22 interconnects a drum cavity/the drum 12 with the tensioning line opening 24. The anchor 14 of the tensioning line 10 may be oversized relative to the tensioning line opening 24 so that the distal end of the tensioning line 10 can be easily retrieved and is not ‘swallowed’ by the winding assembly 16.
Each winding assembly 16 comprises a tensioner 37 in the form of a slotted spindle 40. The tensioner 37 is actuated to pull the tensioning line 10 once the anchor 14 of the tensioning line 10 has been secured to the pallet 3.
The tensioner 37 is rotatably mounted in the winding assembly 16. The tensioner 37 spans across the tensioning line channel 22 and engages with the tensioning line 10.
The illustrated tensioner 37 is rotatable about a lateral, tensioner axis of rotation 62 perpendicular to the vertical axis of rotation of the drum 12. This ensures that the winding assembly 16 is low-height.
In
The lever 19 is operated by being pivotally moved about an input axis of rotation 61 from a rest position (
The illustrated tensioner 37 has a slotted spindle 40 defining a slot 38 through which the tensioning line 10 passes. The tensioner 37 is rotatably held in the winding assembly 16 by bearings 41A, 41B. By rotating the slotted spindle 40 after the tensioning line 10 has been anchored to the pallet 3, the tensioning line 10 is wound around the slotted spindle 40 which pulls any slack in the tensioning line 10 to tension the tensioning line 10.
The movement of the lever 19 from the rest position of the lever 19 to the end of the stroke length of the lever 19 rotates the slotted spindle 40 from a home position of the slotted spindle 40 to a tensioning position of the slotted spindle 40. This wraps the tensioning line 10 around the slotted spindle 40 to tension the anchored tensioning line 10. Only one stroke of the lever 19 is necessary.
When the slotted spindle 40 is at the home position, its slot 38 may be aligned with the direction in which the tensioning line 10 can be wound and unwound, to not resist pulling of the tensioning line 10 therethrough. The slot 38 may be parallel to the tensioning line channel 22. The slot 38 may face the tensioning line opening 24.
When the slotted spindle 40 is at the tensioning position, as shown in
The angular distance from the home position of the slotted spindle 40 to the tensioning position of the slotted spindle 40 may be a reflex angle. The lever 19 may have a stroke length of approximately 180 degrees (or a different, obtuse angle).
Only one stroke of the lever 19 (e.g., 180 degrees) is necessary to rotate the slotted spindle 40 by the reflex angle (e.g., 300 degrees). The mesh drive linkage has the necessary gear ratio to effect this single-stroke operation.
It would be appreciated that a tensioner 37 could be implemented in another manner than via a slotted spindle. For example, the tensioner could comprise an over-centre cam (not shown), rotatable to compress the webbing of a strap 10 against a reaction surface, such as a base of the tensioning line channel 22. As the nose of the cam approaches perpendicular to the reaction surface, the normal compressive force of the tensioning line 10 increases to create sufficient traction to drag the tensioning line 10 back in a tensioning direction. Once the nose of the cam has passed over-centre (nose passes perpendicular), the tensioning line 10 is tensioned. Further it is difficult to unwind the tensioning line 10 by pulling on the tensioning line 10 because pulling hard increases the friction.
For manufacturing optimisation, the tensioner 37 may be a drop-in part that is dropped into a tensioner-receiving channel 44 (a cavity in the winding assembly 16) during manufacture, to rest on the bearings 41A, 41B. A top housing part (not shown) may then be secured to the winding assembly 16 to enclose the tensioner 37 therein.
In
The driver sprocket 18 may be an integral part of the fulcrum body 21 of the lever 19. For example, the lever 19 may be comprised of an elongate handle 20 connected to a sprocket 18, defining a Class 2 lever. The mechanical advantage of the lever 19 is the radius of the distal end of the elongate handle 20 from the input axis of rotation 61, divided by the shorter radius of the driver sprocket 18 from the input axis of rotation 61.
The tensioner drive input sprocket 42 is coaxial with and connected to the slotted spindle 40. The tensioner drive input sprocket 42 may be integrally moulded with, or secured to, the slotted spindle 40. The tensioner drive input sprocket 42 can therefore rotate about the same bearings 41A, 41B as the tensioner 37.
The tensioner axis of rotation 62 of the tensioner drive input sprocket 42 is perpendicular to the input axis of rotation 61 about which the driver sprocket 18 rotates. Therefore, the drive loop 53 can comprise a quarter-twist to connect the axes.
Returning to
The catch 72 operates in the manner of a one-way gate that the lever 19 can enter but cannot leave without first undoing the catch 72. The catch 72 is implemented as a snap-fit catch 72.
The snap-fit catch 72 is in the path of the elongate handle 20. The elongate handle 20 pushes against the snap-fit catch 72 to deflect the snap-fit catch 72 away from its neutral undeflected position, for example by flexing the snap-fit catch 72. The axis of flex/rotation of the snap-fit catch 72 may be a lateral axis. When the elongate handle 20 passes an over-centre detent 74 of the snap-fit catch 72, the snap-fit catch 72 toggles into engagement with the elongate handle 20. The whole elongate handle 20 may be within the detent 74. The detent 74 is hook-shaped to create the over-centre actuation.
The elongate handle 20 is itself shaped to deflect the snap-fit catch 72 until the portion of the elongate handle 20 settles into the detent 74. As shown, the elongate handle 20 comprises a curved surface to deflect the snap-fit catch 72. Alternatively, the surface could be sloped and ramp-like. Likewise, the snap-fit catch 72 comprises a sloped and/or curved deflection surface for deflection by the elongate handle 20. The shape of the detent 74 of the snap-fit catch 72 may also match a portion of the cross-section shape of the elongate handle 20 (e.g., oval shaped in the FIGs).
As shown in
As shown in
To release the elongate handle 20 from the handle retainer 70, the user pushes (e.g., flexes) the catch 72 vertically with their finger, to separate the detent 74 from the elongate handle 20. The deflection surface of the catch 72 may function as the handle releaser by being sized to receive a user's fingertip.
This disengagement of the handle retainer 70 is sufficient to allow the urger of the drum axle 13 to pull the line 14 hard enough to rotate the tensioner 37 back to its home position, the back-rotation of the tensioner 37 causing rotation of the lever 19 back to its rest position. The tensioning line 10 is now slack which allows the user to separate the anchor 14 from the pallet 3 and retract the tensioning line 10.
It would be appreciated that a different type of handle retainer and/or handle releaser could be implemented than that shown, such as a manually operated latch arrangement.
The mesh drive linkage can also be varied.
The mesh drive linkage may provide an interface: tensioner gear ratio of greater than 5:1 or greater than 10:1 or greater than 15:1. In an example implementation, eighteen turns of the interface turns the tensioner 37 by the required reflex angle from the home position to the tensioning position.
In order to prevent over-tensioning of the tensioning line 10 by the tool,
Although only
The parts 18, 42 (or 18A, 42A or 18B, 42B) of the mesh drive linkage may be injection moulded plastics parts. In an example implementation, the driver is a moulded worm drive 18B with a moulded recess 19B.
For manufacturing optimisation, the parts 18, 42 (or 18A, 42A or 18B, 42B) of the mesh drive linkage may be drop-in parts. The driver 18, 18A, 18B may be a drop-in part. For example, in
The retainer 70′ of
The retainer 70′ is configured to engage with the lever 19 following actuation of the lever 19 in the first, tensioning direction (from the rest position of the lever 19 to the end of the stroke length of the lever 19), to prevent movement of the lever 19 in the second, opposite direction despite the bias force from the urger of the drum axle 13 biasing the lever 19 back towards its rest position.
The catch 72′ operates in the manner of a one-way gate that the spiral cam 76 can enter but cannot leave without first undoing the catch 72′. The catch 72′ is implemented as a spring-loaded catch 72′.
As shown in
To release the elongate handle 20 from the retainer 70′, the user pushes a releaser in the form of a release button 78 with their finger, to separate the catch 72′ from the drop of the spiral cam 76. The release button 78 is sized to receive a user's fingertip.
This disengagement of the retainer 70′ by the release button 78 may or may not be sufficient to allow the urger of the drum axle 13 to pull the line 10 hard enough to rotate the tensioner 37 back to its home position. Should the urger of the drum axle 13 not be powerful or consistent enough to cause rotation of the tensioner 37 to its home position, a return spring 82 can be provided.
One end of the illustrated return spring 82 is connected to the slotted spindle 40 and another end of the return spring 82 is attached to the housing of the winding assembly 16. The return spring 82 is wrapped around the slotted spindle 40. The return spring 82 is configured to bias the tensioner 37 back to its home position upon actuation of the release button 78.
If the handle 20 is connected to the slotted spindle 40 via a non-slip drive linkage, then the return spring 82 is able to simultaneously bias the tensioner 37 back to its home position and the lever 19 to its rest position. Otherwise, a separate return spring may be provided for the lever 19 at the cost of an increased part count.
In other implementations, the return spring 82 could be connected to another part of the tensioner load path connecting the handle 20 to the rotation of the slotted spindle 40.
In some examples, a return spring 82 of the type described in relation to
The tensioning line 10 is now slack which allows the user to separate the anchor 14 from the pallet 3 and retract the tensioning line 10.
The release button 78, the catch 72′, and optionally the spring 80, may be an integral part such as an integrally-moulded part. This obviates the need for a mechanism connecting the release button 78 to the catch 72′, or multiple parts during manufacture.
For intuitive use, the release button 78 is an exterior part of the winding assembly. The release button 78 is adjacent the lever 19. The release button 78 is exposed at the upstanding side 5 of the lid 1 of
Since the part comprising the release button 78 is a high-wear item, it can be mounted above the driver 18 for ease of replacement. When a top cap (not shown) of the housing 4b is removed, the part is located at the top of the winding assembly 16 and can therefore be picked out for replacement. This minimises the down-time of a damaged winding assembly 16, and promotes repair rather than replacement.
In the illustrated example, the multi-link mechanism 84 is in the form of a parallel four-link mechanism 84, to linearise a motion of the release button 78 and keep the release button 78 facing a given direction between non-depressed and depressed positions of the release button 78.
The multi-link mechanism 84 comprises a crank 86, a rocker 88, and a connecting rod 90 supported by the crank 86 and rocker 88, wherein the release button 78 is supported by the connecting rod 90.
The crank 86 and rocker 88 may be pivotally connected to the housing 4b (not shown), for example to the top cap. Where the multi-link mechanism 84 is a four-link mechanism, the housing 4b would represent the fourth link in a free body diagram.
A first end of the crank 86 is pivotally supported by the housing 4b. A second end of the crank 86 pivotally supports the connecting rod 90. The connecting rod 90 may be pivotally supported by the crank 86 by a flexure bearing such as a living hinge.
The spring 80 may be connected to any appropriate location on the multi-link mechanism 84 to urge the release button 78 to its non-depressed position. For example, the spring 80 is shown as being connected to the crank 86.
A first end of the rocker 88 is pivotally supported by the housing 4b. A second end of the rocker 88 pivotally supports the connecting rod 90. The connecting rod 90 may be pivotally supported by the rocker 88 by a flexure bearing such as a living hinge.
The catch 72′ may be located anywhere on the multi-link mechanism 84 that is aligned with the spiral cam 76 and which enables the spring 80 to urge the catch 72′ towards the spiral cam 76. For example, the catch 72′ is shown as being formed along the rocker 88.
A first end of the connecting rod 90 may be connected to the crank 86. A second end of the connecting rod 90 may support the release button 78. The rocker 88 may be connected between the first and second ends of the connecting rod 90. The second end of the connecting rod 90 may be cantilevered beyond the rocker 88.
The multi-link mechanism 84 may be movable in a horizontal plane. Therefore, additional height is not required to accommodate the multi-link mechanism 84.
As the handle 20 is turned from the rest position to its full stroke position, the spiral cam 76 slides against the catch 72′ to rotate the multi-link mechanism 84 in a first direction resisted by the spring 80. When the full stroke position is reached, the spring 80 is able to actuate the multi-link mechanism in a second, opposite direction to engage the catch 72′ with the drop of the spiral cam 76.
When the release button 78 is depressed by a user's digit while the handle 20 is at the full stroke position, the connecting rod 90 rotates the rocker 88 and the crank 86 in the first direction resisted by the spring 80. With sufficient depression of the release button 78, the catch 72′ is lifted out of the spiral cam 76, enabling the handle 20 to spring back to its rest position.
When the user's digit is then removed from the release button 78, the spring 80 rotates the crank 86 in the second direction to actuate the multi-link mechanism 84 to return the release button 78 to its non-depressed position, and urge the catch 72′ against the spiral cam 76. The multi-link mechanism 84 may be an integrally-formed part. The multi-link mechanism 84 may be integrally formed with the release button 76, catch 72′, and spring 80.
Although embodiments of the present invention have been described in the preceding paragraphs with reference to various examples, it should be appreciated that modifications to the examples given can be made without departing from the scope of the invention as claimed.
Features described in the preceding description may be used in combinations other than the combinations explicitly described.
Although functions have been described with reference to certain features, those functions may be performable by other features whether described or not.
Although features have been described with reference to certain embodiments, those features may also be present in other embodiments whether described or not.
Whilst endeavoring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2118868.5 | Dec 2021 | GB | national |
| 2118869.3 | Dec 2021 | GB | national |
| 2207960.2 | May 2022 | GB | national |
| 2219325.4 | Dec 2022 | GB | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/IB2022/062659 | 12/22/2022 | WO |