Lifting aid for loading cargo into an ambulance

Abstract

Lifting aid (10) for loading heavy loads, in particular a stretcher chair, in an ambulance, with a) a base frame arranged in an ambulance (12), b) a support structure (14) for receiving the load, c) a movement kinematics (16) arranged between the base frame (12) and the support mount (14), d) an electric linear drive (18) acting on the motion kinematics (16), wherein e) the movement kinematics (16) is designed such that the support mount (14) performs a combined vertical lifting movement and horizontal swiveling movement when extending, characterized by the fact that f) the motion kinematics (16) includes an additional release lever (20) which assists the linear drive (18) during an initial phase of the extension process by introducing an additional horizontal force.

Description

Technical field

[0001] The innovation concerns a lifting aid for loading heavy loads, in particular a stretcher chair, in an ambulance, with a) a base frame arranged in an ambulance, b) a support structure for receiving the load, c) a movement kinematics arranged between the base frame and the support mount, d) an electric linear drive acting on the motion kinematics, wherein e) the movement kinematics are designed such that the support mount performs a combined vertical lifting movement and horizontal swiveling movement when extending. Description

[0002] Lifting aids for loading heavy loads, such as a transport chair, are used particularly in emergency medical services to safely and ergonomically load and unload cargo into and out of ambulances. They serve to support paramedics in lifting and positioning heavy loads and to reduce physical strain. They are typically used in a storage compartment or cargo area of ​​an ambulance, where the transport chair is transported during transit. Here, "transport chair" generally refers to heavy loads. However, other loads such as stretchers or similar items can also be included.

[0003] Lifting aids of this type typically consist of a base frame mounted in the vehicle, a support bracket for the transport chair, and a movement mechanism between these components. A drive, particularly an electric linear actuator, moves the support bracket relative to the base frame, allowing the transport chair to be moved from a retracted transport position to an extended loading or unloading position. This movement can include both vertical lifting and horizontal components, enabling the transport chair to be swung out of its storage compartment and into an ergonomically advantageous transfer position.

[0004] Derartige Hebehilfen müssen einerseits ausreichend tragfähig und betriebssicher ausgelegt sein, andererseits jedoch den begrenzten Bauraum in einem Rettungswagen berücksichtigen. Zudem ist im Rettungsdienst eine hohe Funktionszuverlässigkeit erforderlich, da ein Ausfall der Vorrichtung im Einsatzfall die Arbeitsabläufe erheblich beeinträchtigen kann. State of the art

[0005] German patent DE 102019210672 A1 relates to a lifting device for raising a wheelchair into the interior of a motor vehicle. Disclosed is a vertical lifting device arranged on or in the inside of a vehicle door, as well as a fold-out lifting platform mechanically connected to it for receiving the wheelchair. The vertical lifting device includes a drive mechanism by means of which a wheelchair arranged on the lifting platform, together with a wheelchair user, can be raised to the level of the vehicle floor.

[0006] The lifting platform folds out and features a ramp to compensate for height differences between the lowered position and the ground. The lifting process involves lowering the platform to an external position, rolling the wheelchair onto it, then raising it to vehicle floor level and closing the vehicle door, which causes the platform and wheelchair to swing into the interior.

[0007] Furthermore, the publication describes additional features such as extendable supports for stabilization, strap systems, wheel locking devices, coupling interfaces for mechanical securing, and an electrical charging interface for electrically powered wheelchairs. Automated control of the lifting process is also provided.

[0008] German patent DE 10022933 A1 describes an ambulance table for patient transport vehicles with a lifting and adjustment mechanism. The ambulance table has a base frame and an upper platform with a stretcher mounted on it. Two support arms are mounted on a common pivot axis and are actuated by hydraulic cylinders to allow height adjustment of the upper platform and the stretcher mounted on it. Thus, a vehicle-mounted, hydraulically actuated lifting mechanism for a stretcher is disclosed, in which the height adjustment is achieved via pivoting support arms.

[0009] DE 1910111C relates to a stretcher platform for ambulances with a scissor-type lifting device. The stretcher platform comprises a lower platform frame and an upper platform frame, which are connected to each other via a lifting device. The lifting device is essentially designed as a scissor mechanism with intersecting scissor arms that are connected to each other via joints.

[0010] The scissor arms are partially guided by guide rails, with individual pivot points arranged to be longitudinally movable. This allows for guided height adjustment of the upper support platform relative to the lower support platform. The design serves to raise and lower a stretcher positioned on the support platform inside the vehicle.

[0011] Furthermore, the publication describes support and spring arrangements for damping and stabilizing the movement, as well as locking or detent devices for fixing the stretcher platform at different heights. This design provides stable guidance, secure locking, and controlled lifting movement of the stretcher platform.

[0012] The design features a scissor-like lifting mechanism with guide rails, joint connections, spring elements and locking mechanisms to secure the respective position of the stretcher platform.

[0013] Based on the aforementioned publications, existing lifting devices for rescue vehicles still suffer from the problem that either a comparatively large overall height is required, resulting in a considerable space requirement within the vehicle, or that the power transmission in the initial phase of the lifting process is structurally unfavorable. Particularly with very low-profile designs, short initial lever arms can necessitate high drive forces, leading to larger or more powerful drives and thus increased installation space and costs. Furthermore, existing solutions are not consistently designed to allow manual operation without disassembly of components in the event of an electric drive failure. Revelation of the innovation

[0014] Based on this, the innovation aims to provide a lifting aid for loading heavy loads, such as a stretcher chair, in an ambulance, which enables a combined vertical lifting and horizontal swiveling movement with a shallow depth of installation, ensures favorable power transmission especially in an initial phase of the extension process, and at the same time allows manual operation in an emergency.

[0015] In accordance with the innovation, the problem is solved by using a lifting aid for loading heavy loads, in particular a carrying chair, in an ambulance of the type mentioned above. f) the motion kinematics have an additional disengagement lever which assists the linear drive during an initial phase of the extension process by introducing an additional horizontal force.

[0016] The innovation is based on the principle of combining the compact movement kinematics required for a particularly flat design with targeted power assistance in the initial phase of the extension process. For this purpose, a movement kinematic system is integrated between the base frame located in the ambulance and the stretcher mount. This system is actuated by an electric linear drive and performs a combined vertical lifting movement and a horizontal swiveling movement during extension. This coupled movement allows the stretcher to be lifted from a storage compartment and simultaneously swiveled into a transfer position without requiring separate lifting and swiveling units and their associated additional installation space.

[0017] The design incorporates an additional disengagement lever in the motion kinematics, which assists the linear drive during the initial extension phase by applying an additional horizontal force. In the retracted position of the support bracket, the effective lever arms are particularly short due to the design, resulting in unfavorable force ratios. If the linear drive were to operate alone during this phase, it would have to be correspondingly large to generate the required lifting force. This would result in increased installation space requirements and higher costs.

[0018] The additional release lever introduces a targeted horizontal force component into the motion kinematics during the initial phase. This improves the effective force ratios, allowing the linear drive to be designed with a comparatively low nominal force even in compact designs. Once the support has completed its initial extension and the leverage ratios of the kinematics improve, the linear drive takes over the further movement independently. The force assistance is thus only applied where it is structurally necessary.

[0019] Overall, this design allows for a particularly flat lifting aid that can be integrated into a storage compartment, yet still ensures reliable and effortless loading of the stretcher chair. The combined lifting and swiveling motion, along with the initial power assistance, results in a compact, reliable construction that requires a comparatively small drive unit, thus making efficient use of the available installation space in the ambulance.

[0020] An advantageous design of the inventive lifting aid provides that the additional release lever is only effective within an initial extension stroke of a maximum of 200 mm. During this initial phase of the extension process, the lever ratios are particularly unfavorable due to the design, meaning the linear drive alone would have to exert a higher driving force. The temporally and spatially limited force assistance specifically relieves the drive. After overcoming the critical initial range, the lever ratio of the movement kinematics improves, so that additional assistance is no longer required. Limiting the force effect to a defined initial stroke thus enables a compact yet efficient design of the drive system.

[0021] A preferred design of the innovative lifting aid is such that the release lever disengages after exceeding the initial extension distance. This ensures that the release lever is only effective during the critical initial phase and subsequently does not introduce any further forces into the kinematics. This reduces mechanical stress, avoids unnecessary friction losses, and increases the service life of the components involved. At the same time, the movement sequence after the initial phase remains structurally simple and straightforward.

[0022] In a further advantageous embodiment, the motion kinematics comprise at least two lever arms connected by joints. This joint connection allows for the targeted deflection and transmission of the forces initiated by the linear drive. The lever arms enable a defined movement path of the support, in which lifting and pivoting movements are coupled. The use of multiple lever arms also allows for a compact design while maintaining high stability and load-bearing capacity.

[0023] A preferred design for the lifting aid involves an electromechanical spindle drive for the linear actuator. Such a spindle drive is characterized by precise positioning, a compact design, and good integration into existing vehicle structures. Furthermore, an electromechanical spindle drive enables controlled and smooth movement of the load-bearing device, which is particularly advantageous in emergency services with regard to safety and ease of use.

[0024] In a further advantageous embodiment, the movement kinematics exhibit a self-locking effect, so that the support is held automatically in any position without active control of the linear drive. This reliably prevents unintentional lowering or movement of the support, which is of considerable importance, particularly for occupational safety reasons.

[0025] Additionally, a manually operated emergency release can be provided, allowing the self-locking mechanism to be selectively overridden. The ability to override the self-locking mechanism is particularly important in emergency situations, as manual operation remains possible even in the event of a power failure. This ensures the ambulance remains operational even in the event of technical malfunctions.

[0026] A further preferred design feature of the innovative lifting aid is that the load-bearing platform can be moved manually when de-energized. This allows the operator to safely insert or remove the load-bearing chair from the vehicle even if the drive system fails. This manual mobility increases operational safety and ensures that no additional disassembly steps are required.

[0027] Furthermore, it is advantageous if the base frame is designed as a flat modular assembly for integration into a storage compartment and has a maximum installation depth of 180 mm when retracted. Thanks to its modular design, the lifting aid can be integrated into existing ambulances as a standalone unit or retrofitted. The flat design helps to minimize the restriction of available storage space in the ambulance while still providing a fully functional lifting device.

[0028] In another preferred embodiment, the motion kinematics generate a continuous, simultaneous lifting and pivoting motion. This means that during the extension process, both a vertical lifting and a horizontal pivoting motion occur without these movements being separated in time. The continuous coupling of both motion components results in a particularly smooth and ergonomically advantageous movement sequence. At the same time, the installation space is used efficiently, as no additional guide elements are required for separate movement phases.

[0029] Finally, it is advantageous if the release lever is designed to overcome an unfavorable initial lever arm. In the retracted position of the support mount, the effective lever arm between the drive and the load can be very short, resulting in high required drive forces. During this phase, the release lever selectively alters the force application ratio and increases the effective lever arm, allowing the linear drive to be designed with a lower rated force. This enables a compact and energy-efficient overall design while maintaining high operational reliability.

[0030] Further embodiments and advantages will become apparent from the subject matter of the dependent claims and the drawings with their accompanying descriptions. An exemplary embodiment is explained in more detail below with reference to the attached drawings. Brief description of the drawing Fig. Figure 1 shows a side view of a newly designed, retracted lifting aid. Fig. Figure 2 shows a side view of a newly designed extended lifting aid. Fig. Figure 3 shows a perspective view of a newly designed extended lifting aid. Fig. Figure 4 shows a detailed perspective view of the kinematics as a section of the extended lifting aid according to Fig. 3. Preferred embodiment

[0031] Fig. Figure 1 shows a lifting aid 10 in a side view in the retracted state. In the present embodiment, the lifting aid 10 has a maximum installation depth of 180 mm in the retracted state.

[0032] The lifting aid 10 comprises a base frame 12 and a load-bearing platform 14 for receiving a load, for example, a carrying chair. The base frame 12 is depicted as a substantially vertical support structure. The load-bearing platform 14 is movably arranged relative to the base frame 12. The base frame 12 forms a fixed base unit of the lifting aid 10 and serves to support movable components. A movement mechanism 16 is arranged between the base frame 12 and the load-bearing platform 14.

[0033] In the retracted state, the support bracket 14 is in a folded position close to the base frame 12, resulting in a low overall height for the lifting aid 10. The illustration shows that the movement kinematics 16 are compactly arranged between the base frame 12 and the support bracket 14 in the retracted position, thus achieving a small overall dimension of the lifting aid 10 in the vertical direction.

[0034] Fig. Figure 2 shows the lifting aid 10 according to Fig. 1 in a side view in the extended position. So far, the figure from the previous one. Fig. Since reference numeral 1 corresponds to the same reference numerals, the same reference symbols are used. The base frame 12 is depicted as an essentially vertically extending support structure. The base frame 12 forms the fixed base unit of the lifting aid 10 and serves to support the movable components.

[0035] The motion kinematics 16, comprising a linear actuator 18 and a release lever 20, are arranged between the base frame 12 and the support mount 14. The motion kinematics 16 further includes a lever arm 22 and a parallel pair of lever arms 24. The pair of lever arms 24 is connected to the base frame 12 via a joint arrangement 26. Lever arm 22 is articulated to the base frame 12 via a lower joint 28 and to the support mount 14 via a joint 29. The pair of lever arms 24 is connected to the support mount 14 via an upper joint 30. Each pair of lever arms 24 is actuated by a gas spring 25 (see Fig. 4) hinged.

[0036] In the retracted state, the lever arms 22 and 24 are arranged in a significantly more upright position compared to the extended position. This places the support bracket 14 in a raised position relative to the base frame 12. Simultaneously, it is evident that the support bracket 14 is laterally offset compared to the retracted position, resulting in a horizontal pivoting movement.

[0037] A housing 32 of an electrical control unit for the linear drive 18 is attached to the base frame 12. A drive rod 34 is extended and engages a pivot point 36 of the motion kinematics 16. The extension of the drive rod 34 causes a pivoting movement of the lever arms 22 and 24, thereby generating a combined lifting and pivoting movement of the support mount 14.

[0038] Furthermore, the release lever 20 is shown, which is pivotably mounted on the base frame 12 via a bearing 38. The release lever 20 is connected to the movement kinematics 16 via a coupling element 40, which in this embodiment is designed as a gas spring. In the extended position shown, the release lever 20 is in a pivot position different from that in the retracted position.

[0039] A roller 41 is arranged on the release lever 20, which, in the illustrated state, engages the lever arm 22. The roller 41 is preferably rotatably mounted and serves for low-friction power transmission between the release lever 20 and the lever arm 22. The rolling contact enables a uniform power transmission during the pivoting movement of the release lever 20.

[0040] The illustration shows that the interaction of the linear drive 18, the motion kinematics 16 and the release lever 20 results in a combined vertical lifting and horizontal pivoting of the support mount 14 relative to the base frame 12.

[0041] Fig. Figure 3 shows the lifting aid 10 in a perspective view in its extended position. Where the figure corresponds to the previous figures, the same reference symbols are used. The base frame 12 is designed as an essentially vertical support structure and forms the rear base unit of the lifting aid 10. The perspective view shows that the base frame 12 is designed as a frame-like structure with lateral struts 42, which are an integral part of the base frame 12.

[0042] The motion kinematics 16 are arranged on the base frame 12. The motion kinematics 16 comprise the lever arm 22 and the pair of lever arms 24, which are connected to the base frame 12 via the joint arrangement 26. The perspective view shows that the lever arms 22 and 24 are each designed as rod- or profile-shaped components and are arranged laterally spaced apart from each other, thus creating a stable support structure.

[0043] The first lever arm 22 is articulated to the base frame 12 via the lower joint 28. The pair of lever arms 24 is connected to the support bracket 14 via the upper joint 30. In its extended position, the support bracket 14 is raised above the base frame 12 and pivoted outwards. In the perspective view, the support bracket 14 can be seen as an essentially rectangular, frame-like structure with a support surface 44 for receiving a stretcher chair.

[0044] The linear actuator 18 is arranged between the base frame 12 and the motion kinematics 16. The housing 32 for the electrical control unit is attached to the base frame 12. The drive rod 34 is extended and engages the pivot point 36 of the motion kinematics 16. The spatial arrangement of the linear actuator 18 is clearly visible in the perspective view.

[0045] Furthermore, the release lever 20 is visible, which is pivotably mounted on the base frame 12 via the bearing 38. The release lever 20 is connected to the motion kinematics 16 via the coupling element 40. In the extended position shown, the release lever 20 is pivoted relative to the base frame 12.

[0046] In the perspective view, the roller 41 at the free end of the release lever 20 is also visible. The roller 41 rests above the lever arm 22 and is in force-transmitting contact with it. This arrangement causes the release lever 20 to engage the lever arm 22 at a greater distance than the lower joint 28, so that when the release lever 20 pivots, an additional torque is generated around the lower joint 28. This results in a favorable force transmission for raising the lever arms 22, 24, particularly in the initial phase of the extension process.

[0047] The perspective view illustrates the spatial interaction of the base frame 12, the movement kinematics 16, the linear drive 18 and the release lever 20. In particular, it can be seen that when the linear drive 18 extends, the lever arms 22, 24 perform an uprighting movement, which raises and laterally displaces the support mount 14.

[0048] Fig. Figure 4 shows a detailed perspective view of the movement kinematics 16 as a section of the lifting aid 10 in its extended position. Where this figure corresponds to the previous figures, the same reference numerals are used. The figure particularly illustrates the interaction between the lever arms 22, 24 and the release lever 20.

[0049] The motion kinematics 16 comprise the lever arm 22 and the pair of lever arms 24, which are connected to the base frame 12 via the joint arrangement 26. The joint arrangement 26 is designed as a rotatable connecting element, which allows relative movement of the lever arms 22 and 24 to each other.

[0050] The first lever arm 22 is articulated to the base frame 12 via the lower joint 28. At least part of the base frame 12 is visible in the detailed view.

[0051] Furthermore, the pivot point 36 of the linear drive 18 is identifiable on the motion kinematics 16. The drive rod 34 of the linear drive 18 engages at the pivot point 36 and is extended in the position shown.

[0052] The release lever 20 is pivotally mounted on the base frame 12 via the bearing 38. The pivot axis 46 of the release lever 20 is visible in the detailed view. The release lever 20 is connected via the coupling element 40 to the point of application 48 on the motion kinematics 16, with the point of application 48 being located on the lever arm 22. The roller 41 is located at the free end of the release lever 20, resting above the lever arm 22 and in force-transmitting contact with it.

[0053] The detailed illustration shows that the release lever 20 is pivoted relative to its initial position when extended. As the release lever 20 pivots, the roller 41 transmits an additional force component to the lever arm 22. Due to the line of action being located above the lever arm 22, the effective lever arm is increased relative to the lower joint 28, resulting in a greater righting moment on the movement kinematics 16.

[0054] The arrangement of the coupling element 40 relative to the lever arms 22, 24 illustrates the force transmission from the release lever 20 to the motion kinematics 16. When the linear drive 18 is actuated and the drive rod 34 is extended, the resulting movement does not act exclusively directly on the lever arms 22, 24, but also exerts force on the release lever 20 via the coupling element 40. The release lever 20 pivots about the pivot axis 46, whereby the roller 41 rolls along the lever arm 22 and introduces an additional horizontal force component into the motion kinematics 16.

[0055] As the linear drive 18 extends, the geometric position between the roller 41 and the cam track on the base frame 12 changes, so that the lever arm 20 initially amplifies the torque around bearing 28. This force assistance gradually decreases as the extension process progresses until the roller 41 loses contact with the cam track. After overcoming the critical initial range, the linear drive 18 takes over the further movement independently.

[0056] The detailed illustration thus clarifies the constructive interaction of the release lever 20, the roller 41, the coupling element 40 and the lever arms 22, 24 within the movement kinematics 16 as well as the position-dependent support in the initial phase of the extension process. Reference symbol list 10 Lifting aid 12 basic frames 14 Load capacity 16 Movement kinematics 18 Linear actuator 20 release levers 22 first lever arm 24 pairs of lever arms 25 Gas spring 26 Joint arrangement 28 lower joint between lever arm and base frame 29 Joint second lever arm and support mount 30 upper joint between lever arm and support mount 32 Housings for an electrical control unit 34 Drive rod 36. Pivot point of the linear drive on the motion kinematics 38 bearings of the release lever 40 Coupling element between release lever and movement kinematics 41 roll 42 lateral bracing of the base frame 44 Support surface of the load-bearing mount 46 Swivel axis of the release lever 48 Point of application of the coupling element on the motion kinematics QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] DE 102019210672 A1

[0005] DE 10022933 A1

[0008] DE 1910111C

[0009]

Claims

[1] Lifting aid (10) for loading heavy loads, in particular a stretcher chair, in an ambulance, with a) a base frame arranged in an ambulance (12), b) a support structure (14) for receiving the load, c) a movement kinematics (16) arranged between the base frame (12) and the support mount (14), d) an electric linear drive (18) acting on the motion kinematics (16), wherein e) the movement kinematics (16) is designed such that the support mount (14) performs a combined vertical lifting movement and horizontal swiveling movement when extending, characterized by , that f) the motion kinematics (16) includes an additional release lever (20) which assists the linear drive (18) during an initial phase of the extension process by introducing an additional horizontal force. [2] Lifting aid (10) for loading a stretcher chair into an ambulance according to claim 1, characterized by , that the release lever (20) is only effective within a first extension travel of a maximum of 200 mm. [3] Lifting aid (10) for loading a stretcher chair in an ambulance according to one of claims 1 or 2, characterized by , that the release lever (20) disengages after exceeding the first extension distance. [4] Lifting aid (10) for loading a stretcher chair into an ambulance according to one of the preceding claims, characterized by , that the motion kinematics (16) comprises at least two lever arms (22, 24) connected by joints. [5] Lifting aid (10) for loading a stretcher chair into an ambulance according to one of the preceding claims, characterized by , that the linear drive (18) is designed as an electromechanical spindle drive. [6] Lifting aid (10) for loading a stretcher chair into an ambulance according to one of the preceding claims, characterized by , that the motion kinematics (16) exhibits a self-locking effect. [7] Lifting aid (10) for loading a stretcher chair into an ambulance according to one of the preceding claims, characterized by , that the support (14) can be moved manually when the power is off. [8] Lifting aid (10) for loading a stretcher chair into an ambulance according to one of the preceding claims, characterized by , that the base frame (12) is designed as a flat modular assembly for integration into a storage compartment and has a maximum installation depth of 180 mm when retracted. [9] Lifting aid (10) for loading a stretcher chair into an ambulance according to one of the preceding claims, characterized by , that the motion kinematics (16) generates a continuous simultaneous lifting and pivoting motion. [10] Lifting aid (10) for loading a stretcher chair into an ambulance according to one of the preceding claims, characterized by , that the release lever (20) is provided to overcome an unfavorable initial lever arm.

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