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(11) | EP 0 997 375 A2 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Oar stop |
| (57) A rowing oar or scull button assembly (10) comprising a clamp consisting of first
(12) and second (14) clamp parts which in use substantially encircle an oar or scull
shaft and two securing means, (32,34) each securing means securing adjacent ends of
the first and second clamp parts, in which at least one securing means includes a
screw-threaded member (36,37) rotatable about a first axis (A1), and a lever (38,39)
pivotally connected about a second axis (A2) to the threaded member and selectively
movable from a first position to at least a second position relative to the threaded
member, a threaded portion of the member engaging a co-operating threaded portion
of the second clamp part and a camming surface (44A,46A) of the lever acting to clamp
the corresponding adjacent ends of the first and second clamp parts, rotation of the
lever in the first position about the first axis causing tightening of the securing
means. |
[0002] UK Patent Application No. GB2002707 discloses a rowing oar or scull button comprising a clamp consisting of two substantially arch-shaped members secured together at their ends to form an aperture between them which aperture is adapted for the reception of an oar or scull shaft. Securing means in the form of a nut and bolt secure adjacent ends of the arch-shaped members. A camming lever, threaded bar and nut secure the other adjacent ends of the arch-shaped members. However such an arrangement has proved unsatisfactory since the amount of opening provided by the camming lever is found to be insufficient to easily adjust the position of the button along the length of the oar or scull shaft. Thus in practise adjustment of the scull button is carried out with the use of the lever and also with the use of a separate tool such as a spanner which acts on the nuts or a screwdriver which acts on the slotted head of the bolt.
[0003] The requirement to use additional tools is inconvenient since they are easily misplaced or lost, especially if they are inadvertently dropped into the stretch of water upon which the associated boat is to be rowed. In particular with multi-crewed boats such as "eights" either several tools have to be provided or adjustment of each button has to be carried out sequentially which is particularly time consuming.
[0004] Thus according to the present invention there is provided a rowing oar or scull button assembly comprising a clamp consisting of first and second clamp parts which in use substantially encircle an oar or scull shaft and two securing means, each securing means securing adjacent ends of the first and second clamp parts, in which at least one securing means includes a screw-threaded member rotatable about a first axis, and a lever pivotally connected about a second axis to the threaded member and selectively movable from a first position to at least a second position relative to the threaded member, a threaded portion of the member engaging a co-operating threaded portion of the second clamp part and a camming surface of the lever acting to clamp the corresponding adjacent ends of the first and second clamp parts, rotation of the lever in the first position about the first axis causing tightening of the securing means.
[0005] Preferably at least a part of the movement of the lever from the first position to the second position causing slackening of the securing means.
[0006] Preferably the lever has a third position relative to the threaded member wherein at least a part of the movement of the lever from the first position to the third position causes slackening of the securing means.
[0007] Preferably the camming surface provides for an over-centre action of the lever when moved between the first and second positions and/or the first and third positions.
[0008] Preferably the securing means includes a unitary abutment member which acts in the clamp-load path between the lever and the second clamp part and provides a stop to limit pivotal movement of the lever about the second axis.
[0010] Preferably the lever comprises region, such as a tab, to enable manual gripping and rotation of the lever.
[0011] According to a further aspect of the invention there is provided a securing means for a rowing oar or scull button including a screw threaded member rotatable about a first axis, and a lever pivotally connected about a second axis to the threaded member and selectively moveable from a first position relative to the threaded member wherein the securing means can be tightened to at least a second position relative to the threaded member wherein the securing means is prevented from loosening.
[0012] The invention will now be decribed by way of example only with reference to the drawings in which:-
Figure 1 is an isometric view of an embodiment of a rowing oar or scull button assembly according to the present invention;
Figure 2 is a plan view of figure 1:
Figure 3 is an elevation view of figure 1;
Figure 4 is a partial view of figure 3 with the lever shown in a first position; and
Figure 5 is a partial view of figure 3 with the lever shown in a position intermediate the first and a second position.
[0013] With reference to figures 1-4 there is shown a rowing oar or scull button 10 in the form of a clamp consisting of first clamp part 12 and second clamp part 14. The first and second clamp parts are designed to substantially encircle the shaft of a rowing oar or scull with which the button 10 is to be used. First clamp part 12 includes an arch portion 15 comprising a flanged portion 16 connected to a shaft-engaging portion 18. At first and second ends 15A, 15B of arch portion 15 there is provided first and second clamp portions 20A and 20B.
[0014] Second clamp part 14 includes a U-shaped portion 22 consisting of a flanged portion 24 connected to a shaft-engaging portion 26. At each end 22A, 22B of U-shaped portion 22 there is provided first and second clamp portions 28A and 28B.
[0015] The first clamp portions 20A and 28A are each provided with a hole alignable with a corresponding hole of the second clamp portions 20B and 28B respectively.
[0017] Abutments 31A and 31B are provided to prevent rotation of the corresponding nuts but in further embodiments such abutments may not be necessary, such an embodiment relying on friction between the nut and respective clamp portion.
[0018] Ends 15A and 22A are secured together by securing means 32 and ends 15B and 22B are secured together by securing means 34. Securing 32 and 34 are substantially identical and thus only one will be described in detail.
[0019] Securing means 34 comprises a threaded member in the form of a screw-threaded bar 36, having a first thread axis A1, pivotally connected about a second axis A2 to a lever 38 via a pin 40. Threaded bar 36 includes a threaded portion 42 for engagement with nut 30B. The end of threaded bar 36 remote from the threaded portion 42 includes a hole (not shown).
[0020] Lever 38 is unitary and made from a sheet metal blank. The lever has two flange portions 44 and 46 connected in spaced apart relationship via a connecting portion 48. A tab 50 extends from connecting portion 48 beyond flanges 44 and 46 and is bent so that an end section 52 substantially aligns with the pin 40 (see figure 3). End section 52 includes a hole 54.
[0021] Flanges 44 and 46 include holes through which the pin 40 passes. The pin 40 also passes through the hole in the screw-threaded bar 36. Pin 40 is secured against removal by a peening process.
[0022] Flange portions 44 and 46 are each provided with a camming surface 44A and 46A which together provided a lever camming surface 80 for the lever 38.
[0023] The securing means 34 also includes a unitary abutment member 60 also made from a sheet metal blank and consisting of a flange portion 62, a shaft portion 64 and a clamp portion 66 which lie in face to face relationship with respective flange portion 16, shaft-engaging portion 18, and clamp portion 20B. Shaft portion 64 includes a bridge portion 68 with a stop abutment 70.
[0025] The only difference between securing means 32 and securing means 34 is that the unitary abutment member 72 of secure means 32 is a mirror image of the unitary abutment member 60.
[0026] When assembled the screw-threaded bar 36 passes through washer 74, the hole in clamp portion 66, the hole in clamp portion 20B, the hole in clamp portion 28B, and is then threaded into the nut 30B. The screw-threaded bar 37 of securing means 32 is similarly assembled onto its corresponding components. The method of assembling the button 10 onto the shaft of a rowing oar or scull button is as follows:-
[0027] The button 10 is assembled as shown in figure 1 with the securing means 32 and 34 in a loose condition,
[0028] The button assembly is then slid onto the shaft of a rowing oar or scull and positioned at the required axial location on the shaft. The levers 38 and 39 are pivoted to a first upright position (see figure 4 as regards lever 38) with each lever substantially in line with its corresponding thread axis. The person assembling the button then turns the levers about their thread axes via the tabs 50 and 51 so as to tighten the first and second clamp parts. Once correctly tightened the levers are moved either to a second position relative to the threaded bar (see lever 38 figure 3) or to a third position relative to the bar (see lever 39 figure 3).
[0029] It should be appreciated that in the second position the connecting portion 48 or 49 contacts the corresponding stop abutment 70 or 71 and in the third position the flanges 44,46 or 45,47 contact the corresponding stop abutment 70 or 71.
[0030] Thus by providing both a second and third position for the levers the corresponding threaded bar can be tightened in half turn increments.
[0031] The bridge portion 68 allows the width W of the lever 38 to be reduced whilst still maintaining the distance X between the end of the tab 50 and shaft-engaging portion 18 to allow access for a finger to move the lever from the second position to the first position (see figure 3). Similarly the distance Y which allows finger access to move the lever from the third position to the first position is substantially similar to the distance X.
[0032] The lever camming surface 80 is arranged such that the distance D1 between the second axis A2 and the washer 74 when the lever is in the first position is smaller than the equivalent distance D3 when the lever is in a position intermediate the first and second positions. Also the corresponding distance D2 when lever is in the second position is smaller than the distance D3. This inter-relationship between distances D1, D2 and D3 provide an over-centre action on the lever when moving from the first to the second position. A similar over-centre action is provided when the lever moves from the first to the third position.
[0033] In further embodiments the lever camming surface could be arranged such that in moving from a first position to a second position the clamp is only ever slackened. Under these circumstances no over centre action would be provided.
[0034] In further embodiments the lever camming surface could be arranged such that in moving from a first position to a second position the clamp is only ever tightened, or the camming surface could be formed as a radius about the second axis A2 and as such no tightening would occur when the lever is moved from the first position to the second position. Under these circumstances additional retaining means would be required to ensure the levers remained in their first or second position as appropriate. Such retaining means, eg string, could utilise the holes 54 of each lever to ensure that their relative positions did not change and hence ensure that each securing means does not work itself loose during use.
[0035] In further embodiments the threaded member could be in the form of a nut or the like and the co-operating threaded portion of the second clamp part could be a threaded bar, bolt, screw or the like.
[0036] Preferably the washer 74 is made from a material of different hardness to that used for the levers 38 and 39 and the unitary abutment members 60 and 72. This prevents scuffing of the components when the scull button is being assembled into position. For example the washer 74 can be made from stainless steel type 302 S25 BS5770 PT4 of specification TR 280 280/329 VPN, whereas the levers 38 and 39 and unitary abutment members 60 and 72 can be made from stainless steel type 304 S15 BS1449 PT2 1983 of specification 2B 190 VPN MAX.
1. A rowing oar or scull button assembly 10 comprising a clamp consisting of first 12
and second 14 clamp parts which in use substantially encircle an oar or scull shaft
and two securing means 32,34, each securing means securing adjacent ends of the first
and second clamp parts, in which at least one securing means includes a screw-threaded
member 36,37 rotatable about a first axis A1, and a lever 38,39 pivotally connected
about a second axis A2 to the threaded member and selectively movable from a first
position to at least a second position relative to the threaded member, a threaded
portion of the member engaging a co-operating threaded portion of the second clamp
part and a camming surface 44A,46A of the lever acting to clamp the corresponding
adjacent ends of the first and second clamp parts, rotation of the lever in the first
position about the first axis causing tightening of the securing means.
2. A rowing oar or scull button as defined in claim 1 in which at least a part of the
movement of the lever 38,39 from the first position to the second position causing
slackening of the securing means.
3. A rowing oar or scull button as defined in claim 1 or 2 in which the lever 38,39 has
a third position relative to the threaded member 36,37 wherein at least a part of
the movement of the lever from the first position to the third position causes slackening
of the securing means.
4. A rowing oar or scull button as defined in any preceding claim in which the camming
44A,46A surface provides for an over-centre action of the lever when moved between
the first and second positions and/or the first and third positions.
5. A rowing oar or scull button as defined in any preceding claim in which the securing
means includes a unitary abutment member 60 which acts in the clamp-load path between
the lever and the second clamp part and provides a stop to limit pivotal movement
of the lever about the second axis.
6. A rowing oar or scull button as defined in any preceding claim in which the lever
is unitary and made from a sheet metal blank.
7. A rowing oar or scull button as defined in any preceding claim in which the lever
comprises a region, such as a tab 50,51, to enable manual gripping and rotation of
the lever.
8. A securing means 32,34 for a rowing oar or scull button including a screw threaded
member rotatable 36,37 about a first axis A1, and a lever 38,39 pivotally connected
about a second axis A2 to the threaded member and selectively moveable from a first
position relative to the threaded member wherein the securing means can be tightened
to at least a second position relative to the threaded member wherein the securing
means is prevented from loosening.