Patent Description:
Patient lift apparatuses are generally known in the art. These apparatuses are an important tool for caregivers and medical staff, which tool greatly helps and facilitates patient handling. These apparatuses prevent personnel injuries, especially back injuries, and ensure dignity in patient handling.

Such patient lift apparatuses are for instance disclosed in International (<CIT> and <CIT>. Both publications disclose a patient lift apparatus comprising a supporting frame, a boom portion connected to the supporting frame, and a spreader element coupled to the boom portion via a coupling member, the boom portion and coupling member being joined by a pivot joint allowing the coupling member and associated spreader element to pivot with respect to the boom portion about a pivot axis.

In some other instances, the spreader element may be connected to the boom portion via a simple carabiner arrangement, which arrangement facilitates exchange of the spreader element but is however detrimental in that the spreader element may swing in any direction around the connection point to the boom. Such solutions, while simpler in configuration, therefore require great care from the caregiver to avoid injuries to the patient.

According to International (<CIT>, a friction coupling is provided at the pivot joint, which friction coupling is designed to restrict pivoting movement of the coupling member and associated spreader element. In one embodiment, the friction coupling may furthermore comprise a viscous-type rotary damper, which damper acts to dampen rotation of the coupling member (and associated spreader element) with respect to the boom portion.

While this solution is adapted to restrict erratic movement of the coupling member and associated spreader element during handling of the patient lift apparatus, the damping function and efficiency of this solution is somewhat limited, especially with respect to a reduction of patient rocking movement.

Another problem with the solutions disclosed e.g. in International (<CIT> and <CIT> resides in the coupling of the spreader element to the coupling member, which typically requires tools to allow exchange of the spreader element.

European Patent Publication No. <CIT> discloses a patient lift apparatus comprising a supporting frame, a boom portion connected to the supporting frame, and a spreader element coupled to the boom portion via a quick-release link and quick-release hook. The quick-release link is specifically designed to be coupled to the boom portion by a lifting strap. The spreader element may accordingly swing in many directions about the lifting strap. The patient lift apparatus of European Patent Publication No. <CIT> therefore suffers from substantially the same drawback as the known patient lift apparatuses that make use of the aforementioned carabiner arrangement to couple the spreader element to the boom portion.

European Patent Publication No. <CIT> discloses a patient lift apparatus wherein a linear damper is provided between a boom portion and a mast of the supporting frame. This linear damper is merely exploited for the purpose of damping movement of the boom portion with respect to the mast, the main purpose of the linear damper being to prevent the boom portion from abruptly falling in case of failure of the boom actuator. Furthermore, the linear damper according to European Patent Publication No. <CIT> is located such that it is exposed within the angle formed between the boom portion and the mast, which is detrimental in that this could potentially cause injuries to the patient and/or to the caregivers and medical staff handling the apparatus.

There is therefore a need for an improved solution.

A general aim of the invention is to provide a patient lift apparatus of the aforementioned type, which improves ease of use and especially reduces patient rocking.

A further aim of the invention is to provide such a patient lift apparatus that allows faster and easier exchange of the spreader element and which does not compromise patient handling.

Yet another aim of the invention is to provide such a solution that guarantees that the spreader element is adequately connected to the boom portion and cannot be inadvertently released.

These aims are achieved thanks to the solutions defined in the claims. In accordance with the invention, as recited in claim <NUM>, there is provided a patient lift apparatus comprising a supporting frame, a boom portion connected to the supporting frame, and a spreader element coupled to the boom portion via a coupling member, the boom portion and coupling member being joined by a pivot joint allowing the coupling member and associated spreader element to pivot with respect to the boom portion about a pivot axis. According to the invention, the patient lift apparatus further comprises a quick release mechanism to release the spreader element from the boom portion. This quick release mechanism is an integral part of the coupling member, which coupling member comprises a first coupling element that is pivotably coupled to the boom portion and a second coupling element that is connected to the spreader element and releasably coupled to the first coupling element, thus forming a releasable coupling section between the first and second coupling elements.

The aforementioned releasable coupling section may in particular be designed as a dovetail connection between the first and second coupling elements, in which case the first coupling element may especially comprise a T-shaped extension and the second coupling element a corresponding T-shaped opening adapted to receive the T-shape extension and secure the first coupling element to the second coupling element.

In accordance with this preferred embodiment, the second coupling element can advantageously be releasably translatable with respect to the first coupling element, in which case translation of the second coupling element with respect to the first coupling member preferably takes place along an inclined plane. Furthermore, the releasable coupling section may in particular be designed in such a way that the second coupling element comes to rest against the first coupling element and is supported by the first coupling element when coupled one with the other.

In accordance with a particularly advantageous aspect of the invention, the releasable coupling section may in particular be designed in such a way that complete coupling of the second coupling element onto the first coupling element is ensured by gravity, the second coupling element being automatically locked onto the first coupling element upon complete coupling of the first and second coupling elements.

The quick release mechanism may further comprise a locking-unlocking mechanism adapted to automatically lock and secure the first and second coupling elements one with the other and to manually unlock and release the first and second coupling elements one from the other. In this latter case, the locking-unlocking mechanism can advantageously comprise a movable locking member that is adapted to move alongside a guide portion of the first coupling element between a locking position, in which the movable locking member partly engages into a retaining portion provided in the second coupling element, and an unlocking position, in which the movable locking member is disengaged from the retaining portion. This movable locking member can especially be designed to slide inside a hollow portion of the first coupling element, which hollow portion acts as the guide portion, and to cooperate with a corresponding bore provided in the second coupling element, which bore acts as the retaining portion.

The movable locking member is advantageously moved to the locking position and pressed into engagement with the retaining portion under the action of a spring, the movable locking member being selectively movable to the unlocking position and disengaged from the retaining portion under the action of a manually-actuatable release knob, which knob is preferably positioned along the guide portion and forms and integral part of the movable locking member.

By way of preference, the quick release mechanism is designed to allow toolless release of the spreader element.

Further advantageous embodiments of the invention form the subject-matter of the dependent claims and are discussed below.

Other features and advantages of the present invention will appear more clearly from reading the following detailed description of embodiments of the invention which are presented solely by way of non-restrictive examples and illustrated by the attached drawings in which:.

The present invention will be described in relation to various illustrative embodiments. It shall be understood that the scope of the invention encompasses all combinations and sub-combinations of the features of the patient lift apparatus disclosed herein.

As described herein, when two or more parts or components are described as being connected or coupled to one another, they can be so connected or coupled directly to each other or through one or more intermediary parts.

Referring to <FIG>, there is shown a perspective view of a patient lift apparatus <NUM> in accordance with a preferred embodiment of the invention. Apparatus <NUM> include a supporting frame <NUM> comprising a base <NUM>, a mast <NUM> and legs <NUM> provided at their ends with casters <NUM>. A suitable steering handle <NUM> is provided on the mast <NUM> to allow a caregiver to move and position the apparatus <NUM> according to the needs.

A boom portion <NUM> is connected to the supporting frame <NUM>, namely to mast <NUM>, via a first pivot joint PJ1 thereby allowing the boom portion <NUM> to pivot with respect to the mast <NUM> about a pivot axis PA1. Pivot axis PA1 is understood to be parallel to the y-axis of thée Cartesian coordinate system x-y-z depicted in <FIG>, x-y designating by convention a horizontal plane and z a vertical axis perpendicular to the horizontal plane x-y. An actuator <NUM> is further provided to mechanically assist pivotal movement of the boom portion <NUM> with respect to the mast <NUM>, which actuator <NUM> is mounted on mast <NUM> and connected at one end to the boom portion <NUM>. This actuator <NUM> can for instance be an electrically driven screw-type, hydraulic or pneumatic actuator, as is known in the art.

Positioned at a distal end of the boom portion <NUM>, there is provided a spreader element (or spreader bar) <NUM> which is coupled to the boom portion <NUM> via a coupling member <NUM>. Coupling member <NUM> is connected to the boom portion <NUM> via a second pivot joint PJ2 thereby allowing the coupling member <NUM> (and associated spread element <NUM>) to pivot with respect to the boom portion about a pivot axis PA2 (which other pivot axis PA2 is likewise understood to be parallel to the y-axis). Reference sign 20A in <FIG> designates a point of attachment of the coupling member <NUM> to the boom portion <NUM>, which point of attachment 20A is located on pivot axis PA2.

By restricting movement along the y-axis and allowing the coupling member <NUM> and associated spreader element <NUM> to pivot only in the x-z plane thanks to the pivot joint PJ2, one ensures stability of the spreader element <NUM> when the patient lift apparatus <NUM> is moved in an unloaded state, i.e. without any patient. The spreader element <NUM> is thus held in a stable configuration when approaching a patient, thereby reducing the risk to hit the patient's head.

The spreader element <NUM> depicted in <FIG> is shown as a two-point spreader bar comprising two hook portions <NUM> at both ends of the spreader element <NUM>, which hook portions <NUM> are used to attach a sling (not shown) for holding a patient during lifting and transfer. The illustrated spreader element <NUM> is by no means limiting the scope of the invention and other spreader elements could be used, including spreader elements of varying dimensions and sizes as well as of different types such as four-point spreader bars. As a matter of fact, one key feature of the present invention resides in that the spreader element <NUM> is designed to be easily exchangeable as this will become apparent from reading further the following description. The spreader element <NUM> is designed to be freely rotatable with respect to the coupling member <NUM> about a rotation axis RA.

<FIG> is an enlarged view showing in greater detail the coupling arrangement between the boom portion <NUM>, coupling member <NUM> and spreader element <NUM> of the patient lift apparatus <NUM> of <FIG>. <FIG> shows that the coupling member <NUM> of the preferred embodiment actually comprises two coupling elements <NUM>, <NUM>, namely a first, upper coupling element <NUM> and a second, lower coupling element <NUM>, which coupling elements <NUM>, <NUM> are connected one to the other via a quick release mechanism that will be described in greater detail hereafter.

In the illustrated embodiment, the quick release mechanism is advantageously an integral part of the coupling member <NUM>, the first coupling element <NUM> being pivotably coupled to the boom portion <NUM> at the point of attachment 20A so as to pivot about pivot axis PA2 and form pivot joint PJ2, while the second coupling element <NUM> is connected to the spreader element <NUM> (via a point of attachment 22A) and releasably coupled to the first coupling element <NUM>, thus forming a releasable coupling section <NUM> between the first and second coupling elements <NUM>, <NUM>.

By way of preference, the quick release mechanism of the invention is designed to allow toolless release of the spreader element <NUM>, but modifications could be envisaged to require the use of tools to perform assembly and disassembly of the spreader element <NUM> from the boom portion <NUM> should this be necessary or desired.

In the illustrated embodiment, the releasable coupling section <NUM> is designed as a dovetail connection between the first and second coupling elements <NUM>, <NUM>. Other types of connecting arrangements could however be contemplated to secure the coupling elements <NUM>, <NUM> one with respect to the other and provide the desired function of quick release mechanism of the invention.

<FIG> and <FIG> are cross-sectional views of the coupling arrangement of <FIG> taken along a x-z plane, namely a plane perpendicular to pivot axis PA2 of pivot joint PJ2. <FIG> and <FIG> highlight another part of the quick release mechanism in accordance with this preferred embodiment of the invention, namely a locking-unlocking mechanism <NUM> that is provided on a rear part of the coupling member <NUM>. This locking-unlocking mechanism <NUM> is adapted to automatically lock and secure the first and second coupling elements <NUM>, <NUM> one with the other and to manually unlock and release the first and second coupling elements <NUM>, <NUM> one from the other. Also shown in <FIG> and <FIG> is a movable locking member <NUM> of the locking-unlocking mechanism <NUM>. Reference signs <NUM> and 305A respectively designate a manually-actuatable release knob and contact surface thereof, which knob <NUM> is used to manually unlock and release the first and second coupling elements <NUM>, <NUM> and allow separation thereof at the coupling section <NUM>.

<FIG> and <FIG> further illustrate that the second, lower coupling element <NUM> is coupled to the spreader element <NUM> via a swivel axis <NUM>, which allows free rotation of the spreader element <NUM> about the rotation axis RA. The swivel axis <NUM> is located inside a through-hole <NUM> provided in the second coupling element <NUM> (which through-hole <NUM> is coaxial with rotation axis RA) and held onto the second coupling element <NUM> at point of attachment 22A. The swivel axis <NUM> is also partly visible in <FIG> mounted on the second coupling element <NUM> via the point of attachment 22A.

<FIG> and <FIG> also illustrate the provision of a damping element <NUM> that is coupled between the boom portion <NUM> and the coupling member <NUM>. This damping element <NUM> is designed to damp rocking movement of the coupling member <NUM> and associated spreader element <NUM>, i.e. movement about the pivot axis PA2. This damping element is a linear damper having a first end 50A connected to the boom portion <NUM> at point of attachment 18A (which point of attachment 18A is also visible in <FIG> and <FIG>) and a second end 50B connected to the coupling member <NUM>, namely to the first, upper coupling element <NUM>, at a point of attachment 21A that is offset with respect to the pivot axis PA2 of pivot joint PJ2 in order to damp rocking movement about axis PA2. Linear damper <NUM> can in particular be a pneumatic or hydraulic damper.

By way of preference, as illustrated in <FIG> and <FIG>, the damping element <NUM> is located completely within an inner space of the boom portion <NUM>, thereby ensuring that no part of the damping element <NUM> protrudes outside of the boom portion <NUM>.

Tests carried out by the Applicant have in particular demonstrated that the provision of damping element <NUM> ensures an efficient damping of the patient rocking movement and greatly improves comfort for the patient as a result, which is a considerable improvement over the known solutions. Indeed, the damping arrangement allows to drastically and quickly reduce the amplitude of movement of the patient after only a few oscillation cycles. Rocking of the patient in a sling attached to the spreader element <NUM> is extremely reduced, making the experience for a patient to be transferred a lot easier and causing less anxiety for the patient.

As schematically depicted in <FIG>, the second coupling element <NUM> is releasably translatable with respect to the first coupling element <NUM> along a plane SP, which plane SP is preferably inclined. Arrow R in <FIG> indicates the direction in which the second, lower coupling element <NUM> is translated upon release. It shall be understood that, when in the coupled position, as depicted in <FIG>, the second coupling element <NUM> rests against the first coupling element <NUM> and is supported by the first coupling element <NUM>. Both elements <NUM>, <NUM> are furthermore automatically locked one with respect to the other by means of the locking-unlocking mechanism <NUM>.

<FIG> and <FIG> are perspective views of the coupling member <NUM> shown in <FIG> taken respectively from a front side and a rear side along the x-axis. On the front side of the upper coupling element <NUM>, there is provided an arc-shaped cover member <NUM> that forms a protruding portion on the front of the coupling member <NUM>. This cover member <NUM> can be made e.g. of an adequate shock-absorbent material, such as soft plastic material or the like. This cover member <NUM> is held on a supporting structure (which supporting structure is visible in the cross-sectional view of <FIG>) that is secured onto an upper coupling part <NUM> that forms a main body of the first coupling element <NUM>. On a rear side of the upper coupling part <NUM>, there is provided an aperture 210A that is dimensioned to receive the second end 50B of the aforementioned damping element <NUM> which is secured to the upper coupling part <NUM> - and thus to the coupling member <NUM> - at point of attachment 21A. The upper coupling part <NUM> also receives components designed to ensure the function of the pivot joint PJ2 at point of attachment 20A, allowing pivotal movement about pivot axis PA2.

As depicted in <FIG>, the upper coupling part <NUM> comprises a T-shaped extension <NUM> that protrudes downwards, with a neck portion <NUM> exhibiting a smaller width. This extension <NUM> is designed to cooperate and interact with a corresponding T-shaped opening <NUM> that is provided in a lower coupling part <NUM> forming a main body of the second coupling element <NUM>. This T-shaped opening <NUM> likewise exhibits a neck portion <NUM> that conforms to the shape and dimensions of the neck portion <NUM>, with a shoulder portion <NUM> on both sides. The T-shaped extension <NUM>, T-shaped opening <NUM> and associated neck and shoulder portions <NUM>, <NUM>, <NUM> jointly form the dovetail connection that acts as the releasable coupling section <NUM> in the preferred embodiment. This dovetail connection <NUM>, <NUM>, <NUM>, <NUM>, <NUM> is also partly visible from the side in <FIG> and is discussed in greater detail hereafter with reference to <FIG> and <FIG>.

The locking-unlocking mechanism <NUM> with its movable locking member <NUM> is provided on the rear side of the coupling member <NUM>. As depicted in <FIG>, the movable locking member <NUM> is adapted to move alongside a guide portion <NUM>, <NUM> of the first coupling element <NUM>, namely a guide portion <NUM>, <NUM> of the upper coupling part <NUM>. In the illustrated embodiment, the guide portion <NUM>, <NUM> comprises a longitudinal slit <NUM> that is formed in the upper coupling part <NUM>, which longitudinal slit <NUM> is designed to interact with and guide a corresponding extension <NUM> of the movable locking member <NUM> (see also <FIG> where the extension <NUM> is visible). Also partly visible in <FIG> are a spring <NUM> located inside an upper end of a through-hole <NUM> formed in the upper coupling part <NUM> (which through-hole <NUM> also acts as guide portion for the movable locking member <NUM>) as well as a retaining element <NUM> for the spring <NUM> that is secured at the upper end of through-hole <NUM>. In the illustrated example, spring <NUM> is a compression spring that is interposed between the locking member <NUM> and the retaining element <NUM> and that presses the movable locking member <NUM> downwards to a locking position. In that respect, the manually-actuatable knob <NUM> is designed so that it can be pressed upwards, towards the spring <NUM>, to unlock the locking-unlocking mechanism <NUM> and thereby allow release of the lower coupling element <NUM> from the upper coupling element <NUM>. The contact surface 305A of the release knob <NUM> is preferably structured as illustrated to improve grip (see also <FIG>).

<FIG> is a cross-sectional view of the coupling member <NUM> of <FIG> and <FIG> taken along the x-z plane, which cross-sectional view highlights the structure of the locking-unlocking mechanism <NUM> in accordance with the preferred embodiment. In particular, <FIG> shows a further extension <NUM> of the movable locking member <NUM>, which extension cooperates with a lower part of the spring <NUM>. This extension <NUM> is located together with the spring <NUM> on the upper end of through-hole <NUM>, which through-hole <NUM> extends all the way down to the underside of the upper coupling part <NUM>. <FIG> also shows that the manually-actuatable release knob <NUM> is positioned along the guide portion <NUM>, <NUM> and preferably forms an integral part of the movable locking member <NUM>.

In the illustration of <FIG>, the movable locking member <NUM> is shown in the locking position, pressed downwards under the action of the spring <NUM>. In that respect, the movable locking member <NUM> is further provided with a locking element <NUM> that extends downwards and that is designed to interact with a corresponding retaining portion <NUM> provided in the second coupling element <NUM>, namely in the lower coupling part <NUM>.

In the locking position, as depicted in <FIG>, an end 306A of the locking element <NUM> cooperates with the retaining portion <NUM> to secure the upper and lower coupling parts <NUM>, <NUM> one with respect to the other, and thus the first and second coupling elements <NUM>, <NUM> of the coupling member <NUM>. The end 306A is advantageously shaped to exhibit an inclined surface facilitating engagement of the locking member <NUM> into the retaining portion <NUM>.

When the movable locking member <NUM> is moved manually upwards to an unlocking position by a corresponding actuation on the release knob <NUM>, namely by pushing the movable locking member <NUM> against the force exerted by the spring <NUM>, the locking element <NUM> and thus the movable locking member <NUM> can be disengaged from the retaining portion <NUM>, allowing subsequent release of the lower coupling element <NUM> from the upper coupling element <NUM> along plane SP.

<FIG> and <FIG> are perspective views of the upper coupling part <NUM>, which perspective views are taken respectively from a front side and a rear side of the upper coupling part <NUM>. <FIG> and <FIG> are perspective views of the lower coupling part <NUM>, which perspective views are likewise taken respectively from a front side and a rear side. As depicted in <FIG> and <FIG>, sliding surfaces 210a, respectively 220a, are provided on the upper and lower coupling parts <NUM>, <NUM> (which surfaces 210a, 220a are parallel to plane SP as depicted in <FIG>) to form a sliding arrangement allowing translation of the lower coupling part <NUM> with respect to the upper coupling part <NUM>.

<FIG> also shows the lower end of through-hole <NUM> formed in the upper coupling part <NUM>, which through-hole <NUM> communicates with a bore acting as retaining portion <NUM> that is formed in a corresponding portion of the lower coupling part <NUM> as depicted in <FIG>.

In the illustrated embodiment, it will be appreciated that the movable locking member <NUM> is accordingly designed to slide inside a hollow portion (consisting of longitudinal slit <NUM> and through-hole <NUM>) of the first coupling element <NUM>, which hollow portion acts as guide portion, and to cooperate with a corresponding bore provided in the second coupling element <NUM>, which bore acts as the retaining portion <NUM>.

Adequate positioning and support of the lower coupling part <NUM> with respect to the upper coupling part <NUM> is advantageously ensured by an adequate design of the dovetail connection <NUM>, <NUM>, <NUM>, <NUM>, <NUM>. More precisely, as depicted in <FIG> and <FIG>, a rear end 212B of neck portion <NUM> is designed to be wider than a front end 212A of neck portion <NUM>. As depicted in <FIG> and <FIG>, a rear end 222B of neck portion <NUM> is likewise designed to be wider than a front end 222A of neck portion <NUM>, the overall shape and dimensions of neck portion <NUM> matching that of neck portion <NUM>. As a consequence, the shoulder portion <NUM> is wider at the front than at the rear as this is clearly visible on <FIG>. When the upper and lower coupling parts <NUM>, <NUM> are coupled one to the other as depicted e.g. in <FIG>, the lower coupling part <NUM> comes in abutment with the upper coupling part <NUM>, the rear end 212B of neck portion <NUM> acting as support for the shoulder portion <NUM> of the lower coupling part <NUM>. This arrangement ensures perfect alignment of both parts <NUM>, <NUM> one with respect to the other and guarantee automatic engagement of the locking member <NUM> in the retaining portion <NUM>.

Also visible in <FIG> is the through-hole <NUM>, which is coaxial with the axis of rotation RA and inside which the swivel axis <NUM> (not shown in <FIG>) is held via the point of attachment 22A.

Attachment of the spreader element <NUM> can be performed single handed thanks to the aforementioned coupling arrangement. In that respect, an advantage of the aforementioned coupling section <NUM> resides in that gravity will make sure that engagement of the second coupling element <NUM> onto the first coupling element <NUM> is complete and that both elements <NUM>, <NUM> are automatically locked one with respect to the other thanks to mechanism <NUM>, without this requiring any additional measure to secure the coupling. In the context of the aforementioned embodiment, the user actually gets an immediate feedback that mechanical engagement is complete when the locking member <NUM> automatically gets into engagement in the retaining portion <NUM> as soon as the second coupling element <NUM> comes to rest against the first coupling element <NUM>. Detachment requires another hand to unlock the mechanism <NUM> by actuating the aforementioned release knob <NUM>, which is typically a regulatory demand.

Various modifications and/or improvements may be made to the above-described embodiments without departing from the scope of the invention as defined by the appended claims. For instance, other arrangements could be contemplated in order to implement the releasable coupling section between the first and second coupling elements, the dovetail connection being one possible but particularly advantageous and robust solution.

Claim 1:
A patient lift apparatus (<NUM>) comprising a supporting frame (<NUM>), a boom portion (<NUM>) connected to the supporting frame (<NUM>), and a spreader element (<NUM>) coupled to the boom portion (<NUM>) via a coupling member (<NUM>),
wherein the boom portion (<NUM>) and coupling member (<NUM>) are joined by a pivot joint (PJ2) allowing the coupling member (<NUM>) and associated spreader element (<NUM>) to pivot with respect to the boom portion (<NUM>) about a pivot axis (PA2),
characterized in that the patient lift apparatus (<NUM>) further comprises a quick release mechanism (<NUM>, <NUM>) to release the spreader element (<NUM>) from the boom portion (<NUM>),
and in that the quick release mechanism (<NUM>, <NUM>) is an integral part of the coupling member (<NUM>), which coupling member (<NUM>) comprises a first coupling element (<NUM>) that is pivotably coupled to the boom portion (<NUM>) and a second coupling element (<NUM>) that is connected to the spreader element (<NUM>) and releasably coupled to the first coupling element (<NUM>), thus forming a releasable coupling section (<NUM>) between the first and second coupling elements (<NUM>, <NUM>).