GB2209723A

GB2209723A - Bow-facing rowing arrangement with pivotally mounted inboard end of oar

Info

Publication number: GB2209723A
Application number: GB8819115A
Authority: GB
Inventors: Stanley Paul Witchell
Original assignee: Individual
Current assignee: Individual
Priority date: 1987-09-11
Filing date: 1988-09-09
Publication date: 1989-05-24
Anticipated expiration: 2008-09-09
Also published as: GB8819115D0; GB2209723B

Abstract

Rowing equipment is provided that allows the oarsman to face the direction of travel and to row from the rear thwart of a dinghy to maximise the seating capacity and in the case of a racing shell to dispense with the need for a coxswain. Each oar 1 is arranged so as to be flexibly affixed at its inboard extremity to the centre of the boat in the case of a dinghy and to an outrigger (6) (Fig. 3 not shown) in the case of a racing shell employing in both cases a coupling 2 as the means of attachment acting as a pivot and allowing oar 1 to slide along the gunwhale 3 causing the blade of oar 1 to provide a sweep of water, when pulled by the oarsman at a position intermediate the inboard extremity and the gunwhale engaging part. The blade can conveniently be arranged to automatically feather on the return stroke. <IMAGE>

Description

IMPROVEMENTS IN ROWING EQUIPMENT The invention relates to an improvement in rowing technique particularly concerning the means of propulsion.

According to the invention there is provided a means of propulsion for a rowing boat in which each oar includes a blade portion and a handle portion, the oars being pivotally attached relative to the boat and slideable relative to the gunwhale of the boat, whereby in use the handle portion lies intermediate the pivotal attachment point and the gunwhale-engaging part and the oarsman sits facing the bow of the boat propelling the boat in a forward direction by exerting a pulling force on the said handle portion.

Each oar contacts the gunwhale of the boat at an angle that allows adequate and controlled immersion of the blade into the water and promotes a forward movement to the boat resulting from the pulling action of the oarsman who is facing forward.

The friction of oar to gunwhale can be minimized by the provision of a rolling sleeve on the oar or by a local covering on the gunwhale using a friction reducing material. Such a material could be used for a fixed sleeve on the oar.

The blade of the oar can be feathered in the conventional fashion by the rotation of the oar by the oarsman or by the provision of an angular change or crank to the outboard or blade portion of the oar so as to cause the oar to rotate on the return stroke allowing the blade to assume a feathered position relative to the surface of the water.

The tendency of the oar to rotate in a similar manner on the power stroke would be eliminated by the provision of a rotary stop or limit within the coupling that provides the attachment point at the extremity of the handle portion of the oar to the boat.

A rotary stop or limit could be arranged by the use of a fixed eyelet in the handle portion of the oar operating over a fixed rod on the coupling the relative diametersnfboth contributing to the rotational movement allowable to the oar.

The act of pivotting the oar at the centre of the boat or, in the case of a racing shell, to an outrigger on the side opposite to blade immersion allows a reduction in the length of the oar by the extent of the handle portion of a conventional oar but without a reduction in the sweep of the oar in the water employing the same effort, and extentofmovement of the oarsman's arms.

This reduction in length of the oar by approx. one third results in an oar that is lighter in weight and more economical to produce. It is also easier to handle and to convey in the boot or trunk of the average motor car. This would not apply to a racing oar.

The coupling that anchors the handle portion of the oar to the centre of the boat allows rotation of the oar for the purpose of feathering and allows movement of the oar along the gunwhale. The coupling could be used in twin form so as to accept both oars used independantly of each other the whole coupling preferably being affixed to a thwart of the boat and being easily transferable to alternative thwart positions. In the case of a racing shell the oar position would not need to be transferable.

The advantages of the new equipment over conventional equipment are many and various but the freedom of the oarsman to face the direction of travel must be of paramount importance both from a convenience and safety aspect.

The widely spaced hands of the oarsman close to the gunwhales allows a greater movement or sweep ofthe oars as the oarsman's elbows can move past his body whereas in conventional dinghy practice the oarsman's chest would provide the limit for hand movement.

The dinghy oarsman can sit amidships on the centre thwart or he can sit on the rear thwart facing forward in both cases.

The wide centre thwart ofaconventional three thwart dinghy can seat up to three passengers facing forward free of the legs of the oarsman sitting on the rear thwart and the forward thwart will retain its normal single capacity allowing for up to five people overall instead of the usual four, providing an increase of 25 The smaller type of dinghy would have a capacity raised from its normal compliment of three to four persons - an increase of 33"0.

Alternatively the oarsman could use the centre thwart to better balance the boat if travelling alone. The racing shell would benefit from the elimination of the coxswain and the subsequent reduction in weight resulting from a shortened boat with shortened oars.

The automatic feathering provided by the angular change to the outboard or blade portion of the oar would promote confidence in the less experienced dinghy oarsman and convenience for the established oarsman.

The reduction in oar length provides a lighter, lower cost and infinitely more manageable product when carrying by hand or in a vehicle.

The improvement in rowing equipment in accordance with the invention will now be described by way of example with reference to the accompanying drawing in which: Figure 1. shows a plan view of a three thwart dinghy with the improved rowing equipment fitted to or adjacent to the centre thwart and illustrating the movement of the oar along the gunwhale at the end of the power stroke in View A, and during the return stroke with the oar automatically feathered in View B.

Figure 2. shows a plan view of a three thwart dinghy with the improved rowing equipment fitted to or adjacent to the rear thwart and illustrating the improved passenger capacity afforded by this invention.

In Figure 1. View A. the oar 1 can be seen towards the end of the power or propulsion stroke with the blade vertical to the surface of the water.

To minimize the effort required to propel the boat the oarsman would grip the oars 1 as close to the gunwhale 3 as he would find comfortable, the collar 5 permitting such proximity to the gunwhale 3 without risk of hand abrasion and by virtue of its material of manufacture minimizing the friction between oar 1 and gunwhale 3.

View B illustrates the position of the oar 1 towards the end of the return stroke and shows the cranking or angular change 4 in the oar 1 that promotes automatic feathering. The twin coupling 2 shown immediately in front of the oarsman allows flexibility of oar movement by means of a universal joint and fitted with a stop that disallows the rotation of the oar 1 into the 'feather' position on the propulsion stroke.

Oars 1 and coupling 2 could be permanently affixed together and when detached from the centre thwart (or rear thwart as shown in Figure 2) would leave the boat bare of removable objects of any value.

Additionally both oars 1 and a twin coupling 2 permanently affixed together and in a folded form when detached from the boat would provide a convenient package for handling and conveying.

Figure 2 shows the flexible coupling 2 attached or adjacent to the rear thwart with the oars 1 towards the end of the return stroke illustrating the feathering of the blade promoted by the crank 4 in the oar 1.

With the oarsman in this position the maximum capacity of the thwarts can be utilized.

It will be appreciated that all passengers are free of entanglement with the legs of the oarsman and from the movement of oars 1.

Figure 3 shows a plan view of the forward section of a rowing shell illustrating the improved rowing equipment in the form of a reduced length oar 1 the handle portionofwhich is fitted firmly yet flexibly to the outrigger 6 with the body of oar 1 resting on the gunwhale 3 opposite to outrigger 6 and allowing free movement along the gunwhale 3 during the power and return stroke of the oar 1.

Oar 1 and coupling 2 would be firmly yet flexibly affixed to the outrigger 6 the height of attachment being such as to allow an adequate and controlled immersion of the oar 1 in the water when resting on and sliding along the gunwhale 3.

This arrangment would allow the normal use of the oarsman's sliding thwart and would include collar 5 to obviate the danger of abrasion to the oarsman's hand against gunwhale 3.

Automatic feathering could be arranged by cranking of the oar 1 outboard of the gunwhale 3 but the experienced racing oarsman would not significantly benefit from such an arrangement and would feather by rotating and raising the oar 1 from the surface of the water.

Claims

1. A means for propulsion for a rowing boat, in which each oar in cludes a blade portion and a handle portion, the oar being pivot ally attachable relative to the boat and slidable relative to the gunwhale of the boat, whereby in use the handle portion lies in termediate the pivotal attachment point and the gunwhale-engaging part and the oarsman sits facing the bow of the boat propelling the boat in a forward direction by exerting a pulling force on the said handle portion.

2. A means of propulsion as claimed in Claim 1, in which the pivotal attachment point if located on an outrigger.

3. A means of propulsion as claimed in Claim 1, in which the pivotal attachment point is located within the boat.

4. A means of propulsion as claimed in Claim 3, in which the pivotal attachment point is located on or above the centre line of the boat.

5. A means of propulsion as claimed in Claim 3 or Claim 4, in which the oar is pivotally attachable to the boat via a coupling which is removably attachable to a thwart.

6. A means of propulsion according to any preceding claim, in which the blade portion of the oar is cranked.

7. A means of propulsion according to Claim 6, in which the oar is pivotally attachable to the boat via a coupling which includes a rotary stop to prevent or restrain the oar from rotating on the populsion stroke.

8. A means of propulsion according to Claim 1, including a covering or coating friction-reducing material on the gunwhale and/or on the gunwhale sleeve carried on the gunwhale-engaging part of the oar.

9. A means of propulsion according to Claim 8, in which the friction reducing material is embodied as a rotatable sleeve carried on the gunwhale-engaging part of the oar.

10. A means of propulsion according to Claim 9, in which the sleeve carried a flange to protect the oarsman's hand from abrasion against the gunwhale.

11. A means of propulsion according to any of Claims 5 to 10, in which the oars or each oar are/is pivotally attached to the coupling.

12. A coupling for attachment to a rowing boat, the coupling including means for pivotal attachment thereto of an oar at the end thereof remote from the blade.

13. A coupling according to Claim 12, in combination with an oar or a pair of oars, each oar being pivotally attached thereto at the at the end remote from the blade.

14. A means for propulsion for a rowing boat, substantially as hereinbefore described with reference to and as illustrated in Figure 3 of the accompanying - drawings.

14. A means for propulsion for a rowing boar, substantially as herein before described with reference to and as illustrated in Figures 1 and 2 of the accompanying drawings.

15. A means for propulsion for a rowing boat, substantially as herein before described with reference to and as illustrated in Figure 3 of the accompanying drawings.

Amendments to the claims have been filed as follows 1. A means for propulsion for a rowing boat, in which each oar comprises a cranked portion including a blade, a handle portion and a gunwhale-engaging part, the oar being pivotally and rotatably attachable relative to the boat and slidable relative to the gunwhale of the boat, whereby in use the handle portion lies intermediate the pivotal attachment point and the gunwhale-engaging part and the oarsman sits facing the bow of the boat propelling the boat in a forward direction by exerting a pulling force on the said handle portion, and whereby rotation of the oar in one direction at the end of a stroke causes the blade to leave the water and assume a feathered position and rotation in the other direction causes the blade to re-enter the water in readiness for the next stroke.

2. A means of propulsion as claimed in Claim 1, in which the attachment point is located on an outrigger.

3. A means of propulsion as claimed in Claim 1, in which the attachment point is located within the boat.

4. A means of propulsion as claimed in Claim 3, in which the attachment point is located on or above the centre line of the boat.

5. A means of propulsion as claimed in Claim 3 or Claim 4, in which the oar is pivotally and rotatably attachable to the boat via a coupling which is removably attachable to a thwart.

6. A means of propulsion according any preceding claim, in which the oar is attachable to the boat via a coupling which includes a rotary stop to prevent or restrain the oar from rotating on the propulsion stroke.

7. A means of propulsion according to Claim 1, including a covering or coating of friction-reducing material on the gunwhale and/or on the gunwhale-engaging part of the oar.

8. A means of propuslion according to Claim 7, in which the friction-reducing material is embodied as a rotatable sleeve carried on the gunwhale-engaging part of the oar.

9. A means of propulsion according to Claim 8, in which the sleeve carried a flange to protect the oarsman's hand from abrasion against the gunwhale.

10. A means of propulsion according to any of Claims 5 to 9, in which the oars or each oar are/is pivotally attached to the coupling.

11. A coupling for a propulsion means for a rowing boat according to Claim 1, the coupling including means for pivotal and rotatable attachment thereto of an oar at the end thereof remote from the blade.

12. A coupling according to Claim 11, in combination with an oar or a pair of oars, each oar being pivotally and rotatably attached thereto at the end remote from the blade.

13. A means for propulsion for a rowing boat, substantially as hereinbefore described with reference to and as illustrated in Figures 1 and 2 of the accompanying drawings.