Patent Application
20150283933
The present invention relates to a stow lift system for a vehicle with a movable rear impact guard. The present invention further relates to a vehicle equipped with such a stow lift system and to a system for locking the position of the vehicle with respect to a loading bay of a storage facility.
Stow lift systems, often also referred to also as fold-away lift gate systems, are typically mounted to a support frame at the rear of a vehicle, e.g a truck, trailer or a semi-trailer, to lift payloads on a lift platform between a first level, e.g. where the lift platform is flush with the vehicle bed, referred to also as vehicle loading surface, and a second level, e.g. where the lift platform is flush with the ground, or vice versa. A common type of a stow lift system may include a foldable lift platform, which when not in use, is folded under the vehicle bed, while when needed can be unfolded to create a loading surface. The foldable lift platform may be coupled to the support frame by means of a first connecting mechanism, which first connecting mechanism is movable by means of an actuator mechanism for actuating the lift platform of the stow lift system between the first level and second level.
A rear impact guard may be further provided at the rear of the vehicle for preventing, in the case of a rear impact collision, the colliding vehicle from driving on the underside of the vehicle bed. The rear impact guard of the vehicle may further function as a mechanism for locking the position of the vehicle with respect to a loading bay, during the loading and unloading of products by means for example of fork lifts or electric pallet jacks between the loading bay and the vehicle bed. In this case, the rear impact guard may be arranged to cooperate with a dock lock system of a loading bay so as to prevent the vehicle from moving or seesawing during loading and unloading of the products. Usually, the rear impact guard is mounted at the rear of the vehicle chassis, and is usually arranged to be in the extending position so that during the loading and unloading of products between the loading bay and the vehicle, or vice versa, it can be engaged by the dock lock system of the loading bay. However, when the foldable lift platform is used for loading or unloading products from the ground level, the rear impact guard should be movable between the extended position and a retracted position such that the movement of the foldable lift platform between the first level and second level is not restricted.
U.S. Pat. No. 7,762,756 presents a stow lift system with a rear impact guard that can be moved between the extended position and the retracted position so as to accommodate the movement of the foldable lift platform. However, the stow lift system presented in U.S. Pat. No. 7,762,756 has the disadvantage in that the rear impact guard and the foldable lift platform are directly connected and thereby are arranged to function as one unit. As such, the rear impact guard essentially co-revolves with the foldable lift platform about the support frame axis by the action of the actuators. As a result, in the case where the foldable lift platform is used in combination with a loading bay, e.g. for loading and unloading products between the vehicle and the loading bay, positioning the foldable lift platform at the first level, such that it is flush with the vehicle loading surface may cause the rear impact guard to be moved out of the extended position thereby preventing the locking of the vehicle position using the dock lock system, resulting in the violation of the safety regulations with regards to the loading and unloading of products between a loading bay and a vehicle. Moreover, in the event of a rear impact collision, the force generated during the impact at the rear impact guard will be transferred to the common connecting mechanisms of the stow lift system, which may lead to the damage and possible replacement of the complete stow lift system.
It is an aim of the present invention to provide a stow lift system, also referred to as fold-away lift gate system, with a movable rear impact guard that may be used with a vehicle, such as a truck, a trailer or a semi-trailer.
This aim is achieved according to the invention with the lift system showing the technical characteristics of the first claim.
According to embodiments of the present invention, a stow lift system for a vehicle is provided. The stow lift system comprises a support frame for mounting the lift to the vehicle and a foldable lift platform coupled to the support frame via a first connecting mechanism of the lift system. An actuator may be provided for actuating the first connecting mechanism such that the foldable lift platform can be moved via the first connecting mechanism between a stowed position and an unstowed position. The actuator may be further arranged to move the foldable lift platform when in the unstowed position between the ground level and a vehicle bed level. The stow lift system may be further provided with a rear impact guard comprising a longitudinal support member, which is coupled to the support frame via a second connecting mechanism of the lift system. A holding mechanism of the lift system may be arranged between the support frame and the rear impact guard for applying a holding force on the rear impact guard for holding the rear impact guard in an extended position. The rear impact guard may be arranged to move from the extended position to a retracted position when the foldable lift platform is lowered below the level of the rear impact guard, the rear impact guard being reversibly movable between the retracted position and the extended position when the foldable lift platform is raised above the level of the rear impact guard. The first connecting mechanism may further comprise an engagement mechanism, such that when the foldable lift platform is moved below level of the rear impact guard, the engagement mechanism engages at least one predetermined location of the rear impact guard such that the actuating force generated by the actuator during the movement of the foldable lift platform is transferred to the rear impact guard so as to overcome the holding force applied to the rear impact guard by the holding mechanism and move the rear impact guard from the extending position to the retracted position.
According to embodiments of the present invention, the engagement mechanism is arranged to only engage the rear impact guard at a predetermined moment during the movement of the foldable lift platform. For example, the engagement mechanism may be arranged to engage the rear impact guard at the moment when the foldable lift platform is at the same level with the rear impact guard. Therefore, the movement of the rear impact guard is not entirely coupled to the movement of the foldable lift platform. This arrangement of the foldable lift platform and the rear impact guard may have as an advantage that positioning the lift platform at a certain level, e.g. when the foldable lift platform is flush with the vehicle loading surface, may not influence the position of the rear impact guard with respect to the dock lock system. As a result, the present invention allows for the position of the vehicle to be locked with respect to the loading bay using a dock lock system, even when the foldable platform is used for loading and unloading products between a vehicle and the loading bay of a storage facility. Moreover, since the engagement mechanism and the rear impact guard are not attached to one another via common connecting elements, in the event of a rear collision the force transferred from the rear impact guard to the first connecting mechanism holding the foldable lift platform may be significantly reduced, thereby reducing the risk of completely damaging the stow lift system.
According to embodiments of the present invention, a system for locking the position of a vehicle with respect to a loading bay may be provided. The system comprises a vehicle comprising a stow lift system according to embodiments of the present invention and a loading bay. The loading bay comprising a dock lock system, wherein the dock lock system is arranged to cooperate with the rear impact guard of the stow lift system so as to lock the position of the vehicle with respect to the loading bay.
The invention will be further elucidated by means of the following description and the appended figures.
The present invention will be described with respect to particular embodiments and with reference to certain drawings but the invention is not limited thereto but only by the claims. The drawings described are only schematic and are non-limiting. In the drawings, the size of some of the elements may be exaggerated and not drawn on scale for illustrative purposes. The dimensions and the relative dimensions do not necessarily correspond to actual reductions to practice of the invention.
Furthermore, the terms first, second, third and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a sequential or chronological order. The terms are interchangeable under appropriate circumstances and the embodiments of the invention can operate in other sequences than described or illustrated herein.
Moreover, the terms top, bottom, over, under and the like in the description and the claims are used for descriptive purposes and not necessarily for describing relative positions. The terms so used are interchangeable under appropriate circumstances and the embodiments of the invention described herein can operate in other orientations than described or illustrated herein.
The term “comprising”, used in the claims, should not be interpreted as being restricted to the means listed thereafter; it does not exclude other elements or steps. It needs to be interpreted as specifying the presence of the stated features, integers, steps or components as referred to, but does not preclude the presence or addition of one or more other features, integers, steps or components, or groups thereof. Thus, the scope of the expression “a device comprising means A and B” should not be limited to devices consisting only of components A and B. It means that with respect to the present invention, the only relevant components of the device are A and B. The term stow lift system may be considered to include any lift gate system that can be folded away when not in use.
The term vehicle may be considered to include any vehicle which can be fitted with the stow lift system of present invention, such as a truck, a trailer or a semi-trailer.
Referring to
In order to move the rear impact guard 101 from the extended position to the retracted position, an engagement mechanism 110 may be provided on the first connecting mechanism 102. The engagement mechanism 110 may be arranged to engage at least one location of the rear impact guard 101 at a predetermine moment during the movement of the foldable lift platform 104 between the stowed and unstowed position. For example, the engagement mechanism 110 may be arranged to engage the rear impact guard 101 when the foldable lift platform 104 is at a predetermined level with respect to the rear impact guard 101. Therefore, the rear impact guard 101 may be moved from the extended position to the retracted position by the actuating force generated by the actuator 109 during the movement of the foldable lift platform 104. As a result, with the stow lift system 100 of the present invention the rear impact guard 101 may be moved between the extended and retracted position or vice versa without the need of an additional actuating mechanism, which may complicate the manufacturing of the stow lift system 100 and significantly increase its cost. Furthermore, the arrangement between the engagement mechanism 104 and the rear impact guard 101 may enable the use of the stow lift system 104 for loading and unloading products between a vehicle bed 105 and a loading bay 203 of a storage facility 202, without preventing for the position of the vehicle 201 to be locked with respect to the loading bay 203 using a dock lock system 204.
According to embodiments of the present invention, the longitudinal member of the rear impact guard 101 may be pivotally mounted to the support frame 107 via a second connecting mechanism 106, such that it can be moved from the extended position to the retracted position and vice versa. For example, the second connecting mechanism 106 may comprise at least one hinge 112 for pivotally mounting the longitudinal support member of the rear impact guard 101 to the support frame 107, as shown in
According to embodiments of the present invention, the rear impact guard 101 may comprise contact members 108 arranged to be engaged by the engagement mechanism 110 of the foldable lift platform 104, as shown in
The operation of the stow lift platform will now be described with references
Starting from the stowed position, as shown in
The foldable lift platform 104 may be completely unfolded to form a loading surface for loading and unloading products to and from the vehicle bed 105.
In order to load or unload products from the ground level, the foldable lift platform 104 may be moved from the first level, corresponding to the vehicle bed 105, towards a second level, corresponding to the ground level, such that products can be transferred between the vehicle bed 105 and the ground level.
Once the engagement mechanism 110 comes into contact with the contact members 108 of the rear impact guard 101 the actuating force generated by the actuators 109 during the movement of the foldable lift platform 104 may be transferred to the rear impact guard 101 so as to overcome the holding force applied to the rear impact guard 101 by the holding mechanism 103 and move the rear impact guard 101 from the extending position to the retracted position, a shown in
According to embodiments of the present invention, a system 200 for locking the position of the vehicle 201 with respect to the loading bay 203 of a storage facility 202 may be provided, as shown in
In order to lock the position of a vehicle 201 fitted with a stow lift system 100 according to embodiments of the present invention with respect to the respect to a loading bay 203, the vehicle 201 may be first positioned with the rear end at a predetermined distance from the loading bay 203. A dock lock system 204 may be provided at the loading bay 203 having at one end a locking mechanism. The locking mechanism may be positioned to the longitudinal support member of the rear impact guard 101 of the stow lift system 100 such that the position of the vehicle 201 with respect to the loading bay 203 is locked during the loading and unloading of products between the loading bay 203 and the vehicle 201 and vice versa.
