Patent Description:
Low-cost lifting arrangements, sometimes referred to as jib cranes, swing arms cranes, cantilever hoist cranes or the like, typically have in common that a load is liftable upwards or downwards from a lever arm from which the load hangs in e.g. a wire rope. The lever arm is straight and without joints or telescopic lengthening capabilities. The lifting of the load is achieved by that a motor rotates a drum to wind or unwind the wire rope to/from the drum. In this manner, these types of cranes include a reduced number of moving parts as compared to other more advanced and expensive cranes that have lifting arms with one or more joints or telescopic capabilities, e. g as known from <CIT> and <CIT>, thereby creating savings on both bill of material and cost of operation due to less maintenance.

A particular type of these low-cost lifting arrangements are adapted for indoor environments. This means that the lifting arrangement is limited in height and horizontal extension to be able to fit within e.g. a building, such as house, a warehouse, a storage building or the like.

A typical known low-cost lifting arrangement comprises a vertical support pillar at which a lever arm is turnably connected, e.g. by means of a joint. Thanks to the joint the lever arm can be turned in a horizontal plane e.g. within a range from <NUM> to <NUM> degrees or somewhat more. A lifting unit, including a motor, a wire rope or a chain, for lifting or lowering a load, is attached to the lever arm. To reach different positions the lifting unit is typically movable along the lever arm and the lever arm can be turned. While this lifting arrangement may be well suited for certain applications, a disadvantage may be that maneuverability may not be sufficient in some applications, especially when it is desired to move loads quickly.

Further, lifting arrangements are known from <CIT>, which discloses the preamble of claim <NUM>, and <CIT>.

An object may be to eliminate, or at least reduce, the abovementioned disadvantage.

According to an aspect, there is provided a cantilever hoist device according to claim <NUM>.

Due to that the cantilever arm is hingedly mounted at the distal end of the support column, the cantilever arm is rotatable around a rotational axis. In addition, the drive unit is mounted at the support column, which thus is separate from the cantilever arm, and the drive unit is stationary when the cantilever arm is rotated. In this manner, moment of inertia when the cantilever arm is rotated about the rotational axis is reduced compared to known low-cost lifting arrangements with stiff and rigid cantilever arms. As a result, the cantilever hoist device enables improved maneuverability, e.g. in terms of acceleration in at least one of the radial and tangential directions with respect to the rotational axis.

In some embodiments, a portion of a path along which the lifting medium runs is coincidental with the rotational axis of the cantilever arm. In this manner, the lifting medium is smoothly conveyed to or from the winding body of the drive unit when the load is lifted or lowered. The rotational axis is typically parallel with the support column.

In some embodiments, the lifting medium comprises one or more of a wire rope, a rope, a chain, a fiber, and a string.

In some embodiments, displacement of the load along the cantilever arm <NUM> is solely provided by manual operation. Thus, an overall construction of the cantilever hoist device is provided at a low-cost and reduces maintenance to maintain proper operation.

The various aspects of embodiments disclosed herein, including particular features and advantages thereof, will be readily understood from the following detailed description and the accompanying drawings, which are briefly described in the following.

Throughout the following description, similar reference numerals have been used to denote similar features, such as devices, actions, modules, circuits, parts, items, elements, units or the like, when applicable.

<FIG> depicts an exemplifying cantilever hoist device <NUM> according to some embodiments herein. In this example, the cantilever hoist device <NUM> may be a swing crane, a jib crane, a cantilever hoist crane or the like for use in a spatially limited environment <NUM>, such as an indoors environment, a warehouse, a barrack, a storage with or without walls, completely or semi-covered with a roof or overleaf frame structures <NUM> or the like. Further, the spatially limited environment <NUM> may be a spatially limited outdoors environment of any kind. The outdoor environment <NUM> may similarly have or not have walls, be completely or semi-covered with a roof or overleaf frame structure <NUM> or the like. For example, it may be a storage area for various articles and items that may be stored in such outdoors environment.

The cantilever hoist device <NUM> is adapted for lifting a load <NUM> in the spatially limited environment <NUM>. In particular, the cantilever hoist device <NUM> may be configured to operate, e.g. for purposes of lifting or lowering only, on the load <NUM> having a weight in a range of <NUM>-<NUM>, more preferably <NUM>-<NUM>, and most preferably <NUM>-<NUM>.

The cantilever hoist device <NUM> comprises a support column <NUM>. A length of the support column <NUM> is typically less than <NUM>, preferably in a range of <NUM> to <NUM> and most preferably in a range of <NUM> to <NUM>. A typical length of the support column <NUM> may be about <NUM>. As a non-limiting example, the support column <NUM> may have a square cross-section, whose side is in the range of <NUM>-<NUM>, more preferably <NUM>-<NUM>, and most preferably <NUM>-<NUM>. Further, as a non-limiting example, the support column <NUM> may be made of steel, or other suitable material.

The support column <NUM> has a proximal end <NUM> and a distal end <NUM>. The proximal end <NUM> is adapted to secure the support column <NUM> in an upright position, such as in a vertical position, or substantially vertical position.

The support column <NUM> may include a securing base <NUM>, typically at the proximal end <NUM> of the support column <NUM>. The securing base <NUM> may be a metal plate with holes through which bolts, nails or the like, are insertable and screwable into a floor <NUM>, a ground <NUM>, the overleaf frame structure <NUM> or the like. Moreover, in case the cantilever hoist device <NUM> rest on the floor or ground, the securing base <NUM> may be counter-weight base having a weight that is sufficient to allow the support column <NUM> to rigidly stand on the floor <NUM> or ground <NUM>.

In one example, the proximal end <NUM> is adapted to securely fasten the support column <NUM> on a floor <NUM> of an indoors environment, whereby the support column <NUM> is up-rightly mountable on the floor <NUM>. As an example, the support column <NUM> is mountable vertically at the floor <NUM>.

In another example, as shown in <FIG>, the proximal end <NUM> is adapted to securely fasten the support column <NUM> at the overleaf frame structure <NUM>, whereby the support column <NUM> is up-rightly mountable at the overleaf frame structure <NUM>.

The cantilever hoist device <NUM> further comprises an elongated, stiff, and rigid cantilever arm <NUM> hingedly mounted at the distal end <NUM>. As an example, the cantilever arm <NUM> may be hingedly mounted by means of a joint <NUM> or the like. The cantilever arm <NUM> may be a beam arm, a lever arm, a swing arm or the like.

The cantilever arm <NUM> may typically be rotatable in a range from <NUM> to <NUM> degrees, more preferably from <NUM> to <NUM> degrees and most preferably from <NUM> to <NUM> degrees. Furthermore, the cantilever arm <NUM> has a longitudinal length of less than <NUM>, preferably less than <NUM> and most preferably less than <NUM> or a length of about <NUM>.

In order to facilitate, e.g. reduce stress, the hinged mounting of the cantilever arm <NUM> at the distal end of the support column <NUM>, a wire rope <NUM> may be provided. The wire rope <NUM>, or other offloading element, is provided to off-load e.g. the joint, or hinge, at the distal end of the support column <NUM>. As a result, dimension of the cantilever arm <NUM> may be less than without the wire rope <NUM>. As an example, the cantilever arm <NUM> may have a rectangular cross-section, such as <NUM> x <NUM> or the like. The high of the cantilever arm <NUM> is preferably greater than the width, in order to take advantage of better strength when thus mounted. The width of the cantilever arm <NUM> may be in a range of <NUM>-<NUM> and the height of the cantilever arm <NUM> may be in a range of <NUM>-<NUM>. Other widths and heights of the cantilever arm <NUM> may also be used depending on application. Sometimes, the cantilever arm <NUM> may have a circular cross-section, whose diameter may be e.g. <NUM>-<NUM> or the like. Typically, the diameter may be <NUM>. Further, as an example, the cantilever arm <NUM> may be made of aluminum, steel, composite material, or the like.

Moreover, the cantilever hoist device <NUM> comprises a drive unit <NUM> arranged to displace the load towards or away from the cantilever arm <NUM> using a lifting medium <NUM> passing one or more pulleys <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, such as one or more blocks or the like. The drive unit <NUM> may comprise a motor, an electric motor, a combustion engine, a pneumatic motor, hydraulic motor or the like.

The lifting medium <NUM> may comprise one or more of a wire rope, a chain, a fiber, a line, a cable, a belt, a string, a rope and the like. Typically, the lifting medium <NUM> is non-extendable, or substantially non-extendable, in the longitudinal direction thereof.

The drive unit <NUM> comprises a winding body <NUM> onto which the lifting medium <NUM> is rollable to displace the load <NUM>. Accordingly, the drive unit <NUM> is adapted to roll the lifting medium onto or off the winding body <NUM>. The winding body <NUM> have a cylindrical surface with a circular or oval cross-section perpendicularly to the rotational axis (not illustrated) of the winding body <NUM>. The winding body <NUM> may have other shapes suitable for winding of the lifting medium <NUM>.

A distal end of the lifting medium <NUM> is fixed at a distal end of the cantilever arm <NUM>. Preferably, the lifting medium <NUM> is fixed at a crossbar <NUM>, e.g. at a lower end of the crossbar <NUM>. Thereby, the lifting medium's <NUM> path arrives at the crossbar at a distance from the cantilever arm <NUM>. The crossbar <NUM> is located, such as fixed, integrated with, mounted at or the like, at the distal end of the cantilever arm <NUM>. The crossbar <NUM> may extend longitudinally, e.g. in the same or substantially the same direction as the support column <NUM>.

A proximal end of the lifting medium <NUM> may be fixed at the winding body <NUM>, whereby the lifting medium is rollable onto and off the winding body <NUM> as the winding body <NUM> rotates. The drive unit <NUM> may of course include a gear box and/or other part as well. As an example, the drive unit <NUM> has a power of less than <NUM> W, preferably less than <NUM> W.

Moreover, the wire rope <NUM> may be fixed at the crossbar <NUM>, e.g. at an upper end of the crossbar <NUM>. Thereby, the wire rope <NUM> arrives at the crossbar at a distance from the cantilever arm <NUM>.

The drive unit <NUM> is mounted at the support column <NUM>, at the distal end <NUM> of the support column <NUM>. In this manner, it is achieved that the drive unit <NUM> remains stationary, i.e. the drive unit <NUM> does not rotate, or more, together with the cantilever arm <NUM> when the cantilever arm <NUM> is rotated. Consequently, when the load is moved in a tangential direction, or circularly, with respect to a rotational axis R the weight of the drive unit <NUM> does not contribute to moment of inertia caused by the movement. Thus, the load may more easily be moved quickly from one position above the floor <NUM> to another position above the floor <NUM>. In more detail, at a given force and a given load, the load can be operated, radially and/or tangentially by manual labor, with higher accelerations when using the cantilever hoist device according to the embodiments herein as compared to known cranes of the same type and in the same price range.

Torque may also be referred to as the moment, moment of force, rotational force or turning effect, depending on the field of study.

An advantage may therefore be that the cantilever hoist device may be operated, such as maneuvered, quickly at ease. In turn, due to time savings, there may also be cost savings.

Thanks to the embodiments herein, there is provided an advantageous low-cost, cantilever hoist crane for use in the spatially limited environment with lower moment of inertia than existing cranes of the same type and in the same price-range.

In view of the above, it may be noted that the spatially limited environment <NUM> may impose one or more of the following aforementioned constraints to the cantilever hoist device <NUM>.

In some embodiments, a portion <NUM> of a path along which the lifting medium <NUM> runs, e.g. when lifting or lowering the load <NUM>, is coincidental with the rotational axis R of the cantilever arm <NUM>. As an example, the path runs coincidentally with the rotational axis R in that the path runs along and parallelly with the rotational axis in a same and common axis, i.e. the rotational axis R. In <FIG>, the portion <NUM> is illustrated as a small dot on the axis R, that runs perpendicularly to a plane of the paper. This is advantageous, because a force, e.g. due to the load <NUM>, is directed at the axis R, i.e. the rotational axis of the cantilever arm <NUM>. In this manner, the force causes, via the pulleys and lifting medium, essentially no torque, or very little torque. As a result, any stress, such as torque, caused by the cantilever arm <NUM> is independent, or at least substantially independent, of an angle of rotation about the rotational axis R.

A varying torque caused to the cantilever arm is preferably avoided since, that torque typically causes the cantilever arm to swing, or rotate, about the rotational axis R. Thereby, disadvantageously moving, or rotating, the cantilever arm <NUM> away from an assumed operating position. Accordingly, when the path <NUM> along which the lifting medium runs is coincidental with the rotational axis R, such toque is eliminated, almost eliminated, or at least reduced.

A length of the portion may preferably be in a range of <NUM>-<NUM>, more preferably in a range of <NUM>- <NUM>, and most preferably in a range of <NUM>-<NUM>.

Other portions of the path may e.g. run parallelly with the cantilever arm <NUM>. The other portions may be between a trolley (see below) and the distal end of the cantilever arm <NUM> and/or between the trolley and a proximal end of the cantilever arm <NUM>.

As an alternative, illustrated in <FIG>, a pair of blocks <NUM>, <NUM> may be mounted at the proximal end of the cantilever arm <NUM>. The pair of blocks <NUM>, <NUM> may be a pulley with two wheels adapted to convey and feed the lifting medium <NUM>. In <FIG>, for example, the joint <NUM>, the drive unit <NUM> etc. have been left out for simplicity of the drawings. Each block <NUM>, <NUM> has a respective rotational axis that runs parallelly with the rotational axis R, illustrated by dotted circles. A distance between the circumferences of the blocks is adapted to accommodate the lifting medium <NUM>. In this fashion, an increased or varying torque may be caused by the lifting medium, the load and the pulleys as the cantilever arm <NUM> deviates from a starting position, or neutral position, shown in <FIG>. In the neutral position, none or very little torque is caused to the cantilever arm <NUM> since the force F is directed at the axis R. A central longitudinal axis C of the cantilever arm <NUM> is illustrated as a reference. When deviating from the starting position, as illustrated in <FIG>, an angle of rotation about the rotational axis R increases. The lifting medium <NUM> still runs through the rotational axis R, but due to the pulleys <NUM>, <NUM> the force F is directed at a point, located at a distance D1 from the axis R. Since this distance D1 varies with rotation of the cantilever arm <NUM>, the torque varies with different positions of the cantilever arm <NUM>. In more detail, the force's F direction C1 does not coincide with the central longitudinal axis C as soon as the cantilever arm <NUM> deviates, or at least deviates sufficiently much, from the starting position of <FIG>.

In the aforementioned embodiments, in which the portion <NUM> of the path along which the lifting medium <NUM> runs is coincidental with the rotational axis R, consistent maneuverability over the entire range of operation may be achieved, e.g. over the entire range of rotation of the cantilever arm <NUM>.

In order to keep cost of the cantilever hoist device <NUM> low, displacement of the load <NUM> along the cantilever arm <NUM> is solely provided by manual operation. This may e.g. be achieved by that the lifting medium <NUM> passes one or more pulleys, in more detail a first block <NUM> and a second block <NUM>. The first and second blocks <NUM>, <NUM> may be mounted on a trolley <NUM>. The trolley <NUM> is slidable along the longitudinal length of the cantilever arm <NUM>. Accordingly, the trolley <NUM> and/or the load <NUM> may only be manually displaced in the radial direction with respect to the rotational axis R.

The trolley <NUM> may be a frame structure, e.g. in the form of one or more rectangular frames or the like. Pulleys, or blocks, <NUM>, <NUM> may be arranged to roll along an upper surface of the cantilever arm <NUM>. In this manner, the trolley <NUM> may be conveyed along the cantilever arm <NUM>. The pulleys <NUM>, <NUM> of the trolley <NUM> may be located at a respective corner of the trolley <NUM>.

By means of the first and second blocks <NUM>, <NUM>, a further adjustable portion of the path runs vertically away from the cantilever arm <NUM> and back, possibly via a third block <NUM>. In this manner, the load <NUM> can be lifted upwards or lowered downwards. The first and second blocks <NUM>, <NUM> of the trolley <NUM> may be located at a respective lower corner of the trolley <NUM>. It may be preferred that the diameter of the pulleys <NUM>, <NUM> is less than the diameter of the first and second blocks <NUM>, <NUM>.

At a lower end of the further adjustable portion, the load <NUM> may be hung, e.g. onto the block <NUM>. In some examples, the load <NUM> may be carried by the cantilever hoist device <NUM> via a load carrying and/or attaching device <NUM> that may be attachable to the block <NUM>. Moreover, in some examples, the load carrying and attaching device <NUM> may include an operation handle for controlling the drive unit <NUM>, and thus the lifting of the load <NUM>. By means of the operation handle the drive unit <NUM> may be run forwards or backwards to wind the lifting medium onto or off the winding body <NUM>, whereby the load <NUM> is lifted or lowered, respectively. When a user (not shown) operates or maneuvers the load <NUM>, the user may pull or push the load <NUM> using the load carrying and/or attaching device <NUM>. Although not shown, the operation handle may be connected to the drive unit <NUM> by means of an electrical cable, a data bus or the like. In this context, it may be noted that further portions of the path of the lifting medium run perpendicularly to the cantilever arm <NUM> to reach the load carrying and attaching device <NUM>.

Moreover, also in order to keep cost of the cantilever hoist device <NUM> low, displacement of the load <NUM> in a tangential direction, or rotation, about the rotational axis R is solely provided by manual operation.

In some embodiments, see <FIG>, the cantilever arm <NUM> may be hingedly mounted at the distal end <NUM> of the support column <NUM>, wherein an angle V between the support column <NUM> and the cantilever arm <NUM> is in a range from <NUM> degrees to <NUM> degrees, preferably <NUM>-<NUM> degrees. , and most preferably <NUM>-<NUM> degrees.

As an example, referring to <FIG>, the angle V may be <NUM> degrees, or approximately <NUM> degrees. The load <NUM> and/or the load carrying and/or attaching device <NUM> may then be equally easily maneuverable towards and away from the support column <NUM>.

As an example, referring to <FIG>, the angle V may be in a range of <NUM>-<NUM> degrees. The load <NUM> and/or the load carrying and/or attaching device <NUM> may then be biased to be more easily maneuverable towards the support column <NUM>.

As an example, referring to <FIG>, the angle V may be in a range of <NUM>-<NUM> degrees. The load <NUM> and/or the load carrying and/or attaching device <NUM> may then be biased to be more easily maneuverable away from the support column <NUM>.

Claim 1:
A cantilever hoist device (<NUM>) adapted for lifting a load (<NUM>) in a spatially limited environment (<NUM>), comprising:
a support column (<NUM>) having a proximal end (<NUM>) and a distal end (<NUM>), wherein the proximal end (<NUM>) is adapted to secure the support column (<NUM>) in an upright position,
an elongated, stiff, and rigid cantilever arm (<NUM>) hingedly mounted at the distal end (<NUM>), wherein the cantilever arm (<NUM>) is rotatable around a rotational axis (R) that is parallel with the support column (<NUM>),
a drive unit (<NUM>) arranged to displace the load towards or away from the cantilever arm (<NUM>) using a lifting medium (<NUM>) passing one or more pulleys (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>), wherein the drive unit (<NUM>) comprises a winding body (<NUM>) onto which the lifting medium (<NUM>) is rollable to displace the load (<NUM>),
wherein
the drive unit (<NUM>) is mounted at the distal end (<NUM>) of the support column (<NUM>), characterized in
that the drive unit (<NUM>) remains stationary when the cantilever arm (<NUM>) is rotated.