AU2003266444B2

AU2003266444B2 - Truck side curtain tensioning device

Info

Publication number: AU2003266444B2
Application number: AU2003266444A
Authority: AU
Inventors: Gregory Brown; Hugh Lees
Original assignee: Australian Trailer Solutions Group Property Pty Ltd
Current assignee: Australian Trailer Solutions Group Property Pty Ltd
Priority date: 2002-11-27
Filing date: 2003-11-27
Publication date: 2009-05-28
Anticipated expiration: 2023-11-27
Also published as: AU2003266444A1

Description

P/00/011 Regulation 3.2 AUSTRALIA Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT ORIGINAL TO BE COMPLETED BY APPLICANT Name of Applicant: TRANSTECH RESEARCH PTY LTD Actual Inventors: Gregory BROWN; Hugh LEES Address for Service: CALLINAN LAWRIE, 711 High Street, Kew, Victoria 3101, Australia Invention Title: TRUCK SIDE CURTAIN TENSIONING DEVICE The following statement is a full description of this invention, including the best method of performing it known to us:- -2 TITLE: TRUCK SIDE CURTAIN TENSIONING DEVICE The present invention relates to a truck side curtain tension device designed for rotation of corresponding side curtain tension poles. 5 Side walls of some truck bins or, in the case of an articulated trucks, trailers, consist of side curtains. Opposite ends of side curtains are typically held in position by side curtain tension poles. Upper and lower edges of side curtains are supported by upper and lower tracks which define corresponding upper and lower edges of the truck side walls. The upper and lower tracks are attached respectively to a roof and floor of the bin or 10 trailer. The roof and floor are usually permanent features. A front wall of the bin or trailer is also usually permanent and a corresponding rear wall may be removable. A side curtain is erected by sliding its upper and lower edges along the aforementioned tracks and subsequently rotating one or both of the attached side curtain tension poles to tension the side curtain. When the side curtain is fully tensioned it is taut 15 and lies in a vertical plane. Tension is typically applied to side curtains using a side curtain tension wrench. Side curtain tension wrenches usually include a ratchet wheel which is designed for registry with the side curtain tension pole, via, for example, a spline of the pole. A housing of the side curtain tension wrench is attached to a bin or trailer chassis. Rotation of 20 the ratchet wheel results in corresponding rotation of the side curtain tension pole to tension the corresponding side curtain. Prior to dismantling a side curtain, one of the side curtain tension poles must be released enabling it to unwind and subsequently release tension in the side curtain. Unwinding of side curtain tension poles is usually enabled by: 25 (i) disengagement of a holding pawl of the tension wrench which is designed to maintain tension in the side curtain during idle movement of the handle of the wrench; and (ii) depression of a ratchet pawl lever which disengages a ratchet pawl of the tension wrench. 30 Dismantling of a side curtain also typically requires subsequent fine rotational movement of a side curtain tension pole. The ratchet pawl can inhibit this fine movement and it is therefore usually necessary to simultaneously depress the ratchet pawl lever. However, the requirement to depress the ratchet pawl lever makes dismantling of the side curtain awkward because it means that it needs to be carried out using only one hand.

-3 It is therefore desirable to provide an alternative side curtain tension wrench which enables a person to use two hands to dismantle a side curtain. Accordingly, the present invention provides a side curtain tensioning device comprising a ratchet mechanism adapted for engagement with an elongate tension member 5 of said side curtain to apply torque to said tension member, wherein said ratchet mechanism comprises a ratchet wheel for registry with said tension member, a pivotal handle incorporating a ratchet pawl for uni-directional rotation of said ratchet wheel and a holding pawl to prevent rotation of said ratchet wheel in an unwinding direction, said latching means comprising a latching pawl on said handle for latching said handle in a 10 position wherein said ratchet pawl and said holding pawl are held in a position wherein they are unable to engage said ratchet wheel, whereby said ratchet wheel is in a free wheel position facilitating detachment of said tension member therefrom. The invention will now be further described, by way of example only, with reference to the accompanying drawings in which: 15 Figure 1 is a perspective view of one example of a side curtain tension wrench of the present invention; Figure 2 is a front elevational view of the side curtain tensioning wrench of Figure 1; Figure 3 is a longitudinal sectional view of the wrench of Figures 1 and 2 through 20 line A-A of Figure 2 showing specific examples of ratchet and holding pawl of the tension wrench in engaged positions; Figure 4 is a longitudinal sectional view similar to that of Figure 3 showing the tension wrench in a partially disengaged position; and Figure 5 is a longitudinal sectional view similar to Figure 4 but showing one 25 example of a latch pawl in a latched position. Referred to Figures 1, 2 and 3, one example of a side curtain tension wrench 10 of the present invention generally comprises a housing 12, a ratchet wheel 14, a ratchet arm 16, a ratchet pawl 18, a latch pawl 20, a ratchet pawl lever 22, a holding pawl 24, a latch 26 and a holding pawl disengagement pin 28. The side curtain tension wrench 10 also 30 comprises a notched shaft 30. The notched shaft 30 is located relative to the ratchet wheel 14 by means which will be readily apparent to persons skilled in the relevant art. The housing 12 is attached to a floor or chassis of a truck bin or trailer in a manner which will also be readily apparent to persons skilled in the relevant art so that the notched shaft 30 - 3a extends upwardly for receipt of a side a curtain tension pole (not shown). A notch 32 of the notched shaft 30 is designed to prevent relative rotational movement of a side curtain tension pole and the notched shaft 30. Referring to Figure 3, the side curtain tension wrench 10 includes helical springs 34 5 and 36 which force the ratchet pawl 18 and holding pawl 24 respectively toward the -4 Ratchet wheel 14 to ensure engagement with the ratchet wheel 14. Rotational movement of the ratchet arm 16 in a counter-clockwise or tensioning direction, as viewed in Figure 3, results in corresponding rotational movement of the ratchet wheel 14, notched shaft 30 and corresponding side curtain tension pole (not shown). This rotational movement of the side 5 curtain tension pole results in partial winding of a side curtain, which is attached to the side curtain tension pole, around the side curtain tension pole, thereby increasing tension in the side curtain. When the ratchet arm 16 is rotated so that it has moved approximately 900 from the position of Figure 3, the latch pawl 20 contacts the outer or back surface 26a of the latch 26 thereby preventing further rotational movement of the ratchet arm 16 in a 10 counter-clockwise direction. The side curtain can be further tensioned by subsequently rotating the ratchet arm 16 in a clockwise direction through approximately 900 to return it to the position shown in Figure 3 and subsequently rotating the ratchet arm 16 in a counter clockwise direction. The ratchet wheel 14 is held stationary during the aforementioned clockwise rotational movement of the ratchet arm 16 by the holding pawl 24 as the ratchet 15 pawl 18 slides over an outer surface of ratchet teeth 38 of the ratchet wheel 14. When the side curtain is fully tensioned the ratchet arm 16 can be rotated back to the position shown in Figure 3 so that it is not protruding outwardly from the side of the truck bin or trailer. The ratchet pawl lever 22 and holding pawl disengagement pin 28 enable tension in a side curtain to be released for subsequent retraction of a side curtain as follows. 20 Depression of the ratchet pawl lever 22 against spring 34 disengages the ratchet pawl 18 from ratchet wheel 14 and enables the ratchet arm 16 to be moved freely in a counter clockwise direction towards the position shown in figures 4 and 5 while the ratchet wheel is held stationary by the holding pawl 24. Depression of the ratchet pawl lever 22 also rotates the latch pawl 20 in a counter-clockwise direction, preventing it from engaging the 25 latch 26 when the ratchet arm 16 approaches the end of its travel in the counter-clockwise direction. Movement of the ratchet arm 16 beyond the point of contact between the latch pawl 20 and latch 26 allows the holding pawl disengagement pin 28 to contact the holding pawl 24 and pivot it in a counterclockwise direction, as viewed in Figures 4 and 5, about a holding pawl pivot 40, and against the force of the helical spring 36. This pivotal 30 movement of the holding pawl 24 moves it to a disengaged position 42 shown in Figure 5. With the ratchet arm 16 and holding pawl 24 in the position shown in Figure 5, release of the ratchet pawl lever 22 allows the latch pawl 20 to rotate in a clockwise direction about 4a the pivot 44, under the force of the helical spring 34, until the latch pawl 20 engages the latch 26. Engagement between the latch pawl 20 and latch 26 prevents clockwise rotational -5 movement of the ratchet arm 16 and also prevents pivotal movement of the ratchet pawl 18 in a clockwise direction relative to the pivot 44 so that the ratchet pawl is prevented from engaging the ratchet wheel 14. With the side curtain tension wrench 10 in the position shown in Figure 5 the 5 ratchet wheel 14 is able to freely rotate (free wheel) in either a clockwise or counter clockwise direction enabling a side curtain tensioning pole which is attached to the notched shaft 30 to be similarly rotated for detachment of the side curtain tension pole from the notched shaft 30 and subsequent retraction of the side curtain. For ease of retraction of the side curtain a side curtain tension pole, which is 10 attached to an opposite end of the side curtain to the end that was attached to the notched shaft 30, is designed for rotational movement about an upright axis. It should be evident that the present invention provides an improved tension wrench for side curtains on bins or trailers that enables the user to free both hands for the purpose of dismantling the side curtain. In other words it is not necessary for the user to 15 depress the ratchet pawl 22 with one hand whilst dismantling the side curtain with the other. Various changes and modifications may be made to the embodiment described and illustrated without departing from the present invention.

Claims

1. A side curtain tensioning device comprising a ratchet mechanism adapted for engagement with an elongate tension member of said side curtain to apply torque to 5 said tension member, wherein said ratchet mechanism comprises a ratchet wheel for registry with said tension member, a pivotal handle incorporating a ratchet pawl for uni directional rotation of said ratchet wheel and a holding pawl to prevent rotation of said ratchet wheel in an unwinding direction, said latching means comprising a latching pawl on said handle for latching said handle in a position wherein said ratchet pawl and said 10 holding pawl are held in a position wherein they are unable to engage said ratchet wheel, whereby said ratchet wheel is in a free wheel position facilitating detachment of said tension member therefrom.

2. A tensioning device according to claim 1, wherein said ratchet pawl forms 15 part of a lever pivotally mounted on said handle, the lever extending at least part way along said handle and being biased in a direction away from said handle to cause said ratchet pawl to engage said ratchet wheel.

3. A tensioning device according to claim 2, wherein said latching pawl is part 20 of said lever and is adapted to engage a latch on a body of the device when said handle is at its extremity of pivotal movement in a winding direction of said ratchet wheel and said lever is biased away from said handle.

4. A tensioning device as defined in claim 3, wherein said holding pawl is 25 pivotally mounted on said body and is spring biased to engage said ratchet wheel and prevent rotation of said ratchet wheel in an unwinding direction of said ratchet wheel.

5. A tensioning device according to claim 4, wherein a disengagement pin is provided on said handle to contact said holding pawl when said handle is at said extremity 30 of pivotal movement in said winding direction, thereby causing said holding pawl to disengage said ratchet wheel. -7

6. A tensioning device according to claim 5, wherein said handle cannot be pivoted to its extremity in said winding direction unless said lever is held against said handle, otherwise said latching pawl contacts said latch in a non-latching manner that prevents travel of the handle to said extremity. 5

7. A tensioning device as defined in any one of the preceding claims wherein said elongate tension member is a tension pole of a trailer said curtain.

8. A side curtain tensioning device substantially as herein described with 10 reference to the accompanying drawings.