Temporary guardrail for use when unloading objects from trucks and trailers

Abstract

The present invention relates to a temporary guardrail for use when unloading an object from a stack of objects from a truck or trailer.

Description

[0001] Temporary guardrail for use when unloading objects from trucks and trailers.

[0002] Technical field of the invention

[0003] The present invention relates to safety measures for use during unloading of a truck or trailer.

[0004] Background of the invention

[0005] When unloading a concrete slab from a truck or trailer using a crane, ensuring the utmost safety for all involved is paramount, especially considering the risks associated with working at heights. A critical aspect of this process involves the installation of temporary guardrails or safety nets, particularly when a person is positioned atop the concrete slab to attach the crane hook. This scenario presents a significant risk of falling, which can lead to severe injuries or even fatalities.

[0006] Temporary guardrails serve as a physical barrier and are crucial in preventing falls. They usually consist of a system including a top rail, mid-rail, and toe board, or the like. The top rail, placed about 100 cm above the working level, is designed to withstand a substantial amount of force, ensuring it can protect a worker if they lose balance or trip. The mid-rail prevents workers from falling under the top rail, and the toe board stops tools or other objects from being kicked over the edge, which could create hazards below.

[0007] In scenarios where the installation of guardrails might not be feasible or as an additional layer of protection, safety nets are employed. These nets are strategically placed to catch workers in the event of a fall, significantly reducing the severity of potential injuries. They are particularly useful in situations where workers are required to move around on the slab, as they provide a safety buffer around the perimeter.

[0008] The presence of either guardrails or safety nets is vital when a worker must be on top of the concrete slab to connect the crane hook. This task not only exposes them to the risk of falling from the slab but also involves concentrating on the intricate task of securing the hook, which can distract from the immediate physical environment. The guardrails or safety nets offer a form of passive protection, safeguarding the worker without requiring their active involvement or constant vigilance.

[0009] Moreover, the use of these safety measures aligns with broader health and safety regulations and best practices. They demonstrate a commitment to maintaining a safe work environment, which is not only a legal obligation but also an ethical one, prioritizing the well-being and safety of all workers on site.

[0010] Hence, the implementation of temporary guardrails or safety nets is an indispensable safety measure when unloading concrete slabs by crane. It is especially crucial when a person is required to be on the slab for hook attachment, as it significantly mitigates the risk of fall accidents, ensuring a safer and more secure work environment.

[0011] However, current solutions are time consuming to mount and difficult to fasten.

[0012] US11214971 B1 discloses a guardrail base comprising a base body including a first foot, a second foot separate from and distal from the first foot, and a raised portion between the first foot and the second foot; and a rail mount including a fixed clamp body secured to the base body and a floating clamp body offset from and coupled to the fixed clamp body.

[0013] It is an objective of the present invention to provide a temporary guardrail that solves the above-mentioned problems. Summary of the invention

[0014] The temporary guardrail of the present invention allows for a fast and easy mounting operation. The guardrail is fixed between the truck bed, truck trailer bed, or trailer bed and the stack of objects placed thereon. This allows a worker to safely anchor e.g., a crane hook to the upper object of the stack of objects. The worker then leaves the upper object, and often also the truck bed, truck trailer bed, or trailer bed, and the upper object is then craned off. The operation can now be repeated as a “new” upper object appears. When only one object is left, the temporary guardrail can be removed, and the last object can be craned off.

[0015] One aspect relates to a temporary guardrail for use when unloading an object from a stack of objects on a truck, truck trailer, or trailer, the temporary guardrail comprising a rail part mounted to a base part; wherein the base part comprises at least two base units mounted at a distance from one another along the length of the rail part, and adapted for being positioned between individual pieces of dunnage placed beneath the stack of objects, wherein each base unit comprises:

[0016] - an elongate support structure;

[0017] - a push plate or push block; and

[0018] - a mechanism adapted for moving said push plate or push block up and down relative to said elongate support structure.

[0019] A temporary guardrail is a provisional safety barrier installed at the edge of elevated work areas, such as platforms. Here, the temporary guardrail is to protect a platform in the form of a truck bed, truck trailer bed, or a trailer bed, to prevent falls and enhance safety. The temporary guardrail typically consists of a robust framework including a top rail, and a mid-rail, and optionally, a toe board or lower rail. The top rail is typically positioned at about 100 cm above the working level and is designed to withstand substantial force, preventing workers from going over the edge. As the working level constantly changes when used in connection with a stack of objects as individual objects are removed from the top, the top rail will for the present invention be positioned about 100 cm from the working level (i.e. , the top surface) of the first object to be removed from the stack. As the objects are removed from the stack, the top rail will continuously increase in height from the new working level. Hence, the height of the temporary guard rail according to the present invention may be at least 150 cm, such as within the range of 175 cm to 10 meters, e.g., 2-9 meters, such as 3-8 meters, e.g., 4-7 meters, such as 5-6 meters. The length of the temporary guard rail according to the present invention may be at least 150 cm, such as within the range of 175 cm to 10 meters, e.g., 2-9 meters, such as 3-8 meters, e.g., 4-7 meters, such as 5-6 meters. The mid-rail, located below, e.g., halfway, between the top rail and the working surface, acts as an additional barrier, particularly against falls that could occur under the top rail level. Several mid-rails may be present. The toe board, or lower rail, placed at or near the working level, prevents tools or other objects from slipping off the edge, thereby reducing the risk of injury to anyone below. Constructed to be both sturdy and easily removable, the temporary guardrail according to the present invention offers essential fall protection during unloading activities and is removed once the unloading operation is finished.

[0020] Brief description of the figures

[0021] Figure 1 shows a perspective view of a temporary guardrail in accordance with various embodiments of the invention.

[0022] Figure 2 shows a perspective view of a base unit in accordance with various embodiments of the invention.

[0023] Figure 3 shows a perspective view of a rail part in accordance with various embodiments of the invention.

[0024] Figure 4 shows a part of temporary guardrail in accordance with various embodiments of the invention inserted into a space defined by individual pieces of dunnage placed beneath a stack of objects.

[0025] Figure 5 shows a temporary guardrail in accordance with various embodiments of the invention inserted into a space defined by individual pieces of dunnage placed beneath a stack of objects.

[0026] References

[0027] 10 Stack of objects

[0028] 100 Temporary guardrail

[0029] 200 Rail part

[0030] 210 Upper rail

[0031] 220 Lower rail

[0032] 230 Anchor rail

[0033] 300 Base part

[0034] 400 Base unit

[0035] 410 Support structure

[0036] 412 Front part

[0037] 413 Wheel

[0038] 414 Rear part

[0039] 415 Handle

[0040] 416 Hinge

[0041] 420 Push plate or push block

[0042] 422 Lower part

[0043] 424 Upper part

[0044] 430 Linear actuator

[0045] 432 Crank Detailed description of the invention

[0046] One aspect relates to a temporary guardrail for use when unloading an object from a stack of objects on a truck, truck trailer, or trailer, the temporary guardrail comprising a rail part mounted to a base part; wherein the base part comprises at least two base units mounted at a distance from one another along the length of the rail part, and adapted for being positioned between individual pieces of dunnage placed beneath the stack of objects, wherein each base unit comprises:

[0047] - an elongate support structure;

[0048] - a push plate or push block; and

[0049] - a mechanism adapted for moving said push plate or push block up and down relative to said elongate support structure.

[0050] In one or more embodiments, the rail part comprises:

[0051] - an upper rail, or top rail; and

[0052] - one or more lower rails, such as one or more mid-rails.

[0053] In one or more embodiments, the rail part further comprises an anchor rail extending along the length of the rail part and adapted as anchorage for a horizontal lifeline, e.g., via a trolley, slider, or hook. The anchor rail is typically positioned at the same level as the lower rails, such as positioned at the same level as a mid-rail.

[0054] A horizontal lifeline is an advanced fall protection system designed to offer safety and mobility for workers operating at heights, especially in situations where lateral movement is required. This system consists of a flexible line, typically a cable or synthetic rope, rigged between two anchor points. What sets it apart is its anchor rail system, usually made of steel or aluminum, installed along the work area. This rail acts as a track for a hook, trolley, or slider connected to the lifeline, allowing the line to smoothly follow the worker as they move across a horizontal plane.

[0055] The integration of the trolley or slider may be preferred, as it moves freely along the rail but will lock in place during a fall, effectively arresting the fall and minimizing the distance the worker can fall. This feature is complemented by energy absorbers, which are part of the system to reduce the forces exerted on the worker and the anchor points in the event of a fall. These absorbers play a vital role in dissipating the energy generated during a fall, thereby reducing potential injuries.

[0056] In the context of loading and transporting goods, a supportive structure is used that not only creates space for lifting equipment but also helps in stabilizing the load. When used as a simple beam or bar, it elevates the cargo off the floor / bed of the trailer, allowing for easier access by forklift forks. This kind of supportive structure is essential in logistics and freight operations to ensure safe and efficient handling of goods. The supporting structure is often referred to as “dunnage”. In the present context, the term “dunnage” also covers pallets that defines a space for the forks of a forklift. Dunnage can be made from various materials including wood, metal, or plastic. The space generated by the dunnage is utilized by the present invention. It allows the at least two base units to be positioned between individual pieces of dunnage placed beneath the stack of objects.

[0057] In one or more embodiments, the elongate support structure comprises a front part, and a rear part.

[0058] In one or more embodiments, the elongate support structure comprises a front part, and a rear part; wherein the front part is adapted for being positioned between individual pieces of dunnage placed beneath the stack of objects, preferably configured as support for the push plate or push block. Preferably, the rear part is configured as an anchor or connection point for the rail part. In one or more embodiments, the rear part is further configured as a stop, such as a protrusion extending towards the rail part, for preventing the rear part from being positioned between individual pieces of dunnage placed beneath the stack of objects.

[0059] In one or more embodiments, the front part comprises one or more wheels, e.g., adapted for assisting a user in moving the front part beneath the stack of objects. The temporary guardrail is typically craned into position in front of the stack of objects, and a user aids in pushing or directing the elongate support structure, preferably only the front part of the elongate support structure, into the space formed by the dunnage below the stack of objects. The wheels make this operation easier.

[0060] In one or more embodiments, the rear part comprises a handle, e.g., adapted for assisting a user in moving the front part beneath the stack of objects, e.g., by providing a better grip on the rear part.

[0061] In one or more embodiments, the push plate or push block comprises a lower part, and an upper part, wherein the upper part is releasably fastened to the lower part. This configuration makes it possible to adjust the height of the push plate’s or push block’s reach. Hence, the upper part functions as a height extension for use with relatively larger diameter pieces of dunnage.

[0062] In one or more embodiments, the mechanism adapted for moving said push plate or push block up and down relative to said elongate support structure comprises a linear actuator. Linear actuators are devices that create motion in a straight line. They come in various forms and are used across a wide range of applications to move or control mechanisms or systems. In one or more embodiments, the push plate or push block is hingedly connected to the elongate support structure. The hinges preferably form part of the mechanism adapted for moving said push plate or push block up and down relative to said elongate support structure. When the linear actuator acts (either by pushing or dragging) on the push plate or push block, the hinges may be configured to act as guides for the movement of the push plate or push block to restrict the upwards and / or downwards movement.

[0063] In the context of a push plate mechanism, the choice of linear actuator depends on specific needs like force, speed, and precision.

[0064] Electric linear actuators, including electromechanical and piezoelectric actuators, use electric motors or the piezoelectric effect to produce precise linear motion. These are common in industrial machinery for their precise control.

[0065] Hydraulic linear actuators utilize hydraulic fluid pressure to generate motion and force. Known for their power, they're ideal for heavy-duty applications in industrial machinery. Pneumatic linear actuators operate similarly but use compressed air. They are typically faster, though less powerful than their hydraulic counterparts.

[0066] Mechanical linear actuators, like lead screw or ball screw and rack and pinion actuators, convert rotary motion into linear motion using mechanical means. These are appreciated for their simplicity and high precision.

[0067] Magnetic linear actuators, which use magnetic fields to produce linear motion, are precise and commonly used in applications where control and speed are paramount.

[0068] It should be noted that embodiments and features described in the context of one of the aspects of the present invention also apply to the other aspects of the invention. Referring to Figure 1 , a preferred embodiment is shown. The temporary guardrail 100 is shown comprising a rail part 200 mounted to a base part 300. The rail part 200 comprises an upper rail 210, four lower rails 220, and an anchor rail 230 (easier seen in Figure 3). As said, the anchor rail 230 forms part of a horizontal lifeline system, why in general, the horizontal lifeline system could also be seen as part of the temporary guardrail 100. The anchor rail 230 is mounted, here welded, to one of the lower rails 220, and extends along the length of the rail part 200. It is adapted as anchorage for a horizontal lifeline, e.g., via a trolley, slider, or hook (not shown).

[0069] The base part 300 is here shown comprising two base units 400A, 400B mounted at a distance from one another along the length of the rail part 200. Three, or four, or five, or even more base units may in general be present, dependent on the length of the rail part 200. Each base unit 400A, 400B is adapted for being positioned between individual pieces of dunnage (not shown) placed beneath the stack of objects 10 (see Figures 4 and 5). In principle, a single base unit 400 is also possible, and contemplated within the scope of the invention, for relatively short rail parts. Such constructs are only recommended to be used in plural, i.e. , in a side-by-side relationship, such as two or more guardrails.

[0070] Each base unit 400A, 400B comprises an elongate support structure 410, a push plate or push block 420, and a mechanism adapted for moving said push plate or push block 420 up and down relative to the elongate support structure 410 (see Figure 2).

[0071] The purpose of the push plate or push block 420 is that it, when operated, exerts a force onto the bottom of the stack of objects 10, which forces the elongate support structure 410 down towards the bed on which the stack of objects 10 are positioned. In this way, the base unit 400 acts as a wedge, securing the guardrail between the stack of objects 10 and the trailer or truck bed. The push plate or push block 420 is in this embodiment also shown comprising a lower part 422, and an upper part 424. The upper part 424 is releasably fastened to the lower part 422, thereby functioning as a height extension for use with relatively larger diameter pieces of dunnage. The mechanism adapted for moving said push plate or push block 420 up and down relative to the elongate support structure 410 is here shown comprising a mechanical linear actuator 430 operably coupled to a crank 432. When the crank is operated in one direction, the linear actuator 430 drags in the push plate or push block 420, which forces the hinges to rotate and thereby moves the push plate or push block 420 upwards. When the crank is operated in the opposite direction, the linear actuator 430 pushes the push plate or push block 420, which forces the hinges to counterrotate and thereby moves the push plate or push block 420 downwards.

[0072] In Figure 2, the elongate support structure 410 is shown comprising a front part 412, and a rear part 414. The front part 412 is adapted for being positioned between individual pieces of dunnage (not shown) placed beneath the stack of objects 10 (see Figures 4 and 5). Furthermore, the front part 412 is configured as support for the push plate or push block 420, here hingledly mounted thereto.

[0073] The rear part 414 is configured as an anchor or connection point for the rail part 200, and in collaboration, they serve as a stop for preventing the rear part 414 from being positioned between the individual pieces of dunnage placed beneath the stack of objects 10. The rear part 414 also comprises a handle 415, which is useful for assisting a user to get a better grip on the rear part 414 when the front part 412 is moved beneath the stack of objects 10. As an additional assistance in this operation, the front part 412 is provided with a (front) wheel 413.

Claims

Claims1 . A temporary guardrail (100) for use when unloading an object from a stack of objects (10) on a truck, truck trailer, or trailer, the temporary guardrail (100) comprising a rail part (200) mounted to a base part (300); wherein the base part (300) comprises at least two base units (400) mounted at a distance from one another along the length of the rail part (200), and adapted for being positioned between individual pieces of dunnage placed beneath the stack of objects, characterized in that each base unit (400) comprises:- an elongate support structure (410);- a push plate or push block (420); and- a mechanism adapted for moving said push plate or push block (420) up and down relative to said elongate support structure (410).

2. The temporary guardrail (100) according to claim 1 , wherein said mechanism comprises a linear actuator (430).

3. The temporary guardrail (100) according to any one of the claims 1-2, wherein the rail part (200) comprises:- an upper rail (210), or top rail; and- one or more lower rails (220).

4. The temporary guardrail (100) according to claim 3, wherein the rail part (200) further comprises an anchor rail (230) extending along the length of the rail part (200) and adapted as anchorage for a horizontal lifeline, e.g., via a trolley, slider, or hook.

5. The temporary guardrail (100) according to any one of the claims 1-4, wherein the elongate support structure (410) comprises a front part (412), and a rear part (414); wherein the front part (412) is adapted for being positioned between individual pieces of dunnage placed beneath the stack of objects (10), and configured as support for the push plate or push block (420), and wherein therear part (414) is configured as an anchor or connection point for the rail part (200).

6. The temporary guardrail (100) according to claim 5, wherein the rear part (414) is further configured as a stop, such as a protrusion extending towards the rail part (200), for preventing the rear part (414) from being positioned between individual pieces of dunnage placed beneath the stack of objects (10).

7. The temporary guardrail (100) according to any one of the claims 5-6, wherein the front part (412) comprises one or more wheels (413), e.g., adapted for assisting a user in moving the front part (412) beneath the stack of objects (10).

8. The temporary guardrail (100) according to any one of the claims 5-7, wherein the rear part (414) comprises a handle (415), e.g., adapted for assisting a user in moving the front part (412) beneath the stack of objects (10), e.g., by providing a better grip on the rear part (414).

9. The temporary guardrail (100) according to any one of the claims 1-8, wherein the push plate or push block (420) comprises a lower part (422), and an upper part (424), wherein the upper part (424) is releasably fastened to the lower part (422), thereby functioning as a height extension for use with relatively larger diameter pieces of dunnage.

10. The temporary guardrail (100) according to any one of the claims 1-9, wherein the push plate or push block is hingedly connected to the elongate support structure.

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