Abstract
A dock bumper is provided. The dock bumper includes a housing holding a plurality of rollers arranged in an array. The plurality of rollers are arranged to absorb impact from a reversing vehicle. Upon impact, outer surfaces of the rollers are arranged to rotate relative to the frame. Consequently, scrubbing between the vehicle and dock bumper is reduced as are excess forces acting on fixings between the frame and wall. Also, a surface area at each contact location is increased as a cushioning effect is provided by rotation of the roller, thereby prolonging the operation life of the rollers. Furthermore, in one form, the dock bumper is modularized so that only worn or damaged rollers need be replaced at one time.
Claims
1. A method of protecting a loading bay from damage, the method comprising: securing a dock bumper to a wall of a loading bay to be protected, the dock bumper having a housing for connection to the wall, and the loading bay being for use by heavy goods vehicles having airbrakes, wherein: the housing of the dock bumper holds a plurality of impact elements arranged in an array, each of the impact elements being allowed to roll freely within the housing when the dock bumper is secured to the wall of the loading bay; the housing comprises (i) an outer housing, (ii) an inner housing coupled to the outer housing by a plurality of fixing members, and (iii) a plurality of pockets that are each formed from an opening in the outer housing and a corresponding recess in the inner housing, each pocket at least partially containing one of the plurality of impact elements; each of the impact elements is spaced from the wall of the loading bay by at least the inner housing; each of the impact elements is adapted so that abutment of the impact element by a vehicle causes an outer surface of the impact element to move towards the wall to absorb a portion of the force generated by the abutment; and each of the impact elements comprises (i) an impact absorbing member and (ii) an outer sheath arranged about the impact absorbing member, the outer sheath being relatively rigid compared to the impact absorbing member.
2. The method of claim 1, further comprising replacing at least one of the plurality of impact elements of the dock bumper that has become damaged.
3. The method of claim 1, further comprising causing the vehicle to abut an impact element of the plurality of impact elements.
4. The method of claim 1, wherein for each of the plurality of impact elements, the outer sheath has a lower coefficient of friction than the impact absorbing member.
Description
(1) For a better understanding of the invention, and to show how embodiments of the same may be carried into effect, reference will now be made, by way of example, to the accompanying diagrammatic drawings in which:
(2) FIGS. 1 and 2 are perspective views of a front and back respectively of a dock bumper in accordance with a first exemplary embodiment;
(3) FIG. 3 is a front, side and top isometric views of the dock bumper of the first exemplary embodiment;
(4) FIG. 4 is a cross sectional view through A-A of FIG. 3;
(5) FIG. 5 is a perspective front view of a dock bumper according to a second embodiment;
(6) FIG. 6 is a perspective front view of a dock bumper according to a third embodiment;
(7) FIG. 7 is a perspective view of a front of a dock bumper according to a fourth embodiment;
(8) FIG. 8 is an exploded perspective view of the dock bumper according to the fourth embodiment;
(9) FIG. 9 is a perspective view of a front of a dock bumper according to a fifth embodiment; and
(10) FIG. 10 is an exploded perspective view of the dock bumper according to the fifth embodiment.
(11) Referring to FIG. 1, a dock bumper 10 is provided. The dock bumper 10 comprises a frame 20 supporting a plurality of rollers 100. The plurality of rollers 100 are arranged to absorb impact from a reversing vehicle. Upon impact and subsequent raising or lowering of the vehicle, outer surfaces 110 of the rollers 100 are arranged to rotate relative to the frame 20. Consequently, scrubbing between the vehicle and dock bumper is reduced as are excess forces acting on fixings between the frame 20 and wall. Also, a surface area at each contact location is increased as a fresh area is provided by rotation of the roller, thereby prolonging the operational life of the rollers. Furthermore, the dock bumper is modularised so that only worn or damaged rollers need be replaced at one time.
(12) Referring to FIGS. 1 to 3, the frame has a generally u-shaped cross section. The frame is shown as a bent plate forming a base plate 22, and two opposed sides 24, 26. However, other forming and constructional methods are applicable. The opposed sides 24, 26 include fixings for receiving the rollers 100. Referring to FIG. 4, the fixings are apertures through the opposed sides 24, 26. The fixings are spaced to arrange the rollers at appropriate spacing along the height of the dock bumper.
(13) Referring to FIG. 4, each roller 100 includes an impact absorbing member 110 and an outer sheath 120. The impact absorbing member 110 and outer sheath 120 are fixed together so as to rotate as one piece. The parts may be fixed together via a variety of methods. However, a compression fit where the outer sheath is made undersized as opposed to the uncompressed size of the impact absorbing member so that the impact absorbing member is compressed when the sheath is fitted thereby creating a frictional force to lock the two parts together has been found to be particularly suitable. The impact absorbing member 110 is an elongate cylinder formed from a material having a high resiliency to absorb an impact force. For instance, a rubber, polymer passed member having elastic properties or Ethylene Propylene Diene Monomer (EPDM). The outer sheath provides protection to the impact absorbing member. The outer sheath is selected to have one or more different material characteristics to the impact absorbing layer. For instance, the outer sheath 120 that provides the outer surface of the dock bumper that contacts the vehicle may be selected to have a distinctive colouring for visual recognition, or to have a lower coefficient of friction to reduce any rubbing between the vehicle and dock bumper. The outer sheath may also be selected from a material having a high strength compared to the impact absorbing member so as to maintain its shape during impact.
(14) Referring to FIG. 4, the rollers 100 include a central axle 130 that is arranged to rotate relative to the frame 20. The central axle 130 forms a pin and extends through the sides of the frame and is secured by the fixings on distal ends. A fixing such as a nut 134 secures one end of the central axle and pin head the other. Washers 136 are placed between the nut and pin head and respective sides of the frame 20. The central axle may be arranged to rotate relative to the frame. That is, the central axle may rotate in the apertures. However, in FIG. 4, the central axle is shown as being fixed fast to the frame. Here, an axle sheath 132 is provided that rotates about the central axle. The axle sheath is secured to the impact absorbing member 110. Together, the central axle 130 and axle sheath 132 form an axle component. The central axle provides a rigid core to the roller such that the rotational axis of the roller remains substantially straight during impact. As shown in FIG. 4, it is preferable if the axle sheath also extends through the frame so as to give the central axle greater strength. Consequently, the outer sheath moves relative to the central axle by deformation of the impact absorbing member. It is this movement and deformation or compression of the impact absorbing member that generates the impact absorption of the dock bumper.
(15) The impact absorbing member is fixed fast to the central axle by any suitable method but again, a particularly suitable method has been found to be a compression fit formed by making the axle sheath oversized as compared to a bore in the impact absorbing member within which the axle sheath fits. Because the roller acts a single piece, as the vehicle raises or lowers relative to the loading bay, the rollers are caused to rotate and prevent unnecessary damage or forces from being transferred.
(16) The dock bumpers can be increased in size simply by enlarging the height of the frame 20. Consequently, as can be seen in FIGS. 5 and 6 larger dock bumpers can be provided by simply adding more rollers 100. Although a plurality of rollers is provided, in the exemplary embodiment three rollers are shown. In theory, any number of rollers can be added and embodiments of five or more rollers or seven or more rollers are envisaged. Because only the frame needs to be changed to produce the different height dock bumpers, the manufacturing costs of stock, moulding and tools is reduced.
(17) Referring to FIGS. 7 and 8, a dock bumper 10 according to another embodiment is provided. The dock bumper 10 shows a plurality of impact elements 100 arranged as rollers 100. As can be seen, the rollers comprise an outer sheath and an inner impact absorbing member. The rollers 100 are shown as a one-dimensional array in that the longitudinal axes of the rollers are arranged perpendicular to each other. This one-dimensional array is a single column of rollers 100 and multiple rows. In this example, the rollers 100 have equal sizes so that each length of the rollers 100 is the same. The rollers 100 are partially encased by a housing 20 in that the top surface of the rollers 100 are exposed and positioned to absorb an impact on contact by a vehicle. The housing 20 wraps around the rollers 100 and provides struts that cross the housing and help to separate the rollers 100 when in the rollers 100 are positioned on the dock bumper 10. Suitably a front housing and a rear housing is provided. The front and rear housings a secured together to encase the elements whilst allowing the elements to protrude from the front face. Fixing members 134 are also shown to couple the housing 20. Although not shown, these fixing members 134 can easily be further fixed to a wall. As shown in FIG. 8, the housing 20 comprises an outer housing 20a and an inner housing 20b. The fixing members 134 couple the outer and inner housings 20a,20b such that the rollers 100 are freely held in the dock bumper 10. It is possible however, to further provide axles for the rollers 100 so that the rollers 100 are rotatably fixed. When coupled together, the housing provides pockets for the rollers 100 to be held within and be partially exposed from. These pockets comprise openings 20c in the outer housing 20a and recesses 20d in the inner housing 20b. The recesses 20d correspond to the shape of the rollers 100 so that the rollers 100 can evenly compress into the recess 20d. This helps to spread the compression force and helps to prolong the life of the rollers 100 and of the dock bumper 10 as a whole. The recesses 20d are provided integral to the inner housing 20b but may also be provided as a separate component which can be retro-fitted into the inner housing 20b.
(18) Referring to FIGS. 9 and 10, a dock bumper 10 according to a further embodiment is provided. Here, the impact elements 100 are shown as balls 100. The balls 100 are arranged in a multidimensional array in that a plurality of rows and columns and the array is shown as completely filled with balls 100. The balls 100 are freely held within the housing 20 so that the balls can roll independently in any direction. In the exploded view, the dock bumper 10 shows an outer housing 20a and an inner housing 20b, whereby the outer housing comprises openings 20c and the inner housing 20b comprises recesses 20d which together form pockets in the housing 20. The inner housing is shown with fins on the rear which helps to reduce the material used thus reducing the weight of the dock bumper 10. Although not shown, the dock bumper 10 is provided with multiple locations for fastening the outer housing 20a and inner housing 20b together. These fasteners or fixing members may be separate to the fixing members used to connect the housing 20 to the wall. This allows the outer housing 20a to be easily removed in situ whilst the inner housing 20b remains fixed to the wall. The housing 20 may be coupled by clips which may be integral to the inner housing 20a or outer housing 20b or provided separately.
(19) From the foregoing it will be appreciated that there is provided an improved dock bumper that is able to accommodate upwards or downwards movement of a vehicle at any point in the cycle of the movement of the dock bumper. Moreover, the environmental impact of the dock barrier is reduced because only damaged parts of the dock bumper need be replaced. Furthermore, the dock bumper may be made more cost effectively as only the frame 20 needs to be changed to produce different height dock bumpers.
(20) Although preferred embodiment(s) of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes may be made without departing from the scope of the invention as defined in the claims.
