The present invention relates to an arrangement for a sailing boat furling system having the features of the first part of claim 1. The invention also relates to a furling or reefing system having the features of the first part of claim 16.
Sails that are used on a sailing boat may e.g. comprise the mainsail, spinnaker, jib, headsail, and genoa. The sails are supported by one or more masts, a vertical pole or spar that extends upward from the boat. The mainsail is also supported by a boom attached to the mast to support the bottom part of the mainsail. The sails are attached to lines or wires holding them in place and applying tension to the sails and supporting e.g. the mast. The lines, or wires, are denoted differently depending on location and function or attachment such as headstay, backstay, shrouds, sheets, halyards, etc. The mainsail is easier to control than the other sails since it is attached to the mast and the boom. When not in use, furling sails are furled in.
Wind conditions may require that a sail be used with a reduced area. Reducing the area of the sail is denoted reefing. Reefing in or reefing out to decrease or increase the area of the sail is done depending on e.g. wind conditions. The torque load on the furling system when furling in/out with a non-tensioned, flattering sail is considerably lower than the torque load on a furling system from a partially reefed, tensioned sail subjected to wind loads.
Furling systems generally comprise a gear mechanism and a brake system. Furling in and reefing the mainsail, but also other sails, mean that a considerable torque is created. Many furling systems, here taken to mean furling systems for sailing boats in general, such as furling systems for mainsails, for headsails for gennakers, genoas etc. comprise a motor pack comprising a motor and a gearbox or gear mechanism and a brake unit.
In particular, since the brake in known systems is located furthest down in the system, at the motor, the gear-box and the motor unit have to be over-dimensioned since e.g. the external torque in the outgoing shaft during sailing for example of the main sail can be about several times the maximum torque in the outgoing shaft at roll-in. It is a disadvantage that for example the gear unit and/or the motor unit as well as, in the latter case, the power supply have to be large and space demanding, and over dimensioned.
It is therefore an object of the present invention to provide a solution to one or more of the above mentioned problems. It is a particular object to provide a solution through which a small and compact gear mechanism can be used. It is particularly an object to provide a solution through which a smaller motor pack, particularly with a lower power consumption, can be used. A particular object is to provide a solution through which there is no need for an over dimensioned motor pack. Still further it is an object to provide a solution through which high, and even uncontrolled external torques in an outgoing shaft can be handled. It is also an object to provide a solution through which a small and compact motor unit and gear-box can be used in a furling system.
Other objects are to provide an arrangement and a furling system respectively which is easy to install, demands less space than hitherto known solutions, which furthermore is easy to use and control, and flexible as far as installation is concerned, and which in addition thereto is cheap and can be installed and run at a low cost. It is also an object to provide an arrangement a initially referred to which is reliable and safe, also in situations with high external torque loads, or with uncontrolled, sudden external torque loads.
A particular object is to provide a flexible concept and suggest an arrangement that can be used for different types of sails and for different purposes regarding furling in/out sails of different types, for reefing in/reefing out etc.
Therefore an arrangement as initially referred to is provided which comprises the characteristic features of the characterizing part of claim 1.
Therefore also a furling system as initially referred to is provided which has the characterizing features of claim 16.
Advantageous embodiments are given by the respective appended dependent claims.
The invention will in the following be further described, in a non-limiting manner, and with reference to the accompanying drawings, in which:
The ratchet mechanism arrangement 10 comprises a locking unit and is arranged in a ratchet mechanism housing comprising a ratchet mechanism housing upper part 17B connected to, or taking up, an outgoing shaft 11 and a ratchet mechanism housing lower part 17A. The ratchet mechanism housing lower and upper parts 17A,17B are interconnected by means of screws 16 and bushings 15.
The furling drive unit 20 comprises a gearbox assembly 22 and a motor unit 23. The ratchet mechanism arrangement 10 is connectable to, here, the upper portion of the furling drive unit 20 which comprises holes 25 for taking up the screws 15 or bushings 16. In
In the shown embodiment an external holding torque Text is acting in an external torque direction, here clockwise, on the outgoing shaft 11.
By a controlled movement of the motor unit shaft 21, the outgoing shaft 11 can be shifted from being in a ratchet mode to a free mode and vice versa as will be further described with reference in particular to
The motor unit shaft 21 can take a maximum motor unit torque TMmax.
According to the invention, the motor unit 23 is arranged to control (via the control unit 30) the outgoing shaft 11 such that it can be subjected to a higher static holding torque load (in one direction) than the motor unit 23 can take by means of the ratchet mechanism 10.
In the illustrated embodiment the first direction is clockwise, whereas the second direction is anti-clockwise. It should be clear that the inventive concept also is applicable for the reversed situation, i.e. when a first direction is anti-clockwise and the second is clockwise.
The outgoing shaft 11 can take a maximum holding torque TOhold,max. It should be clear that the arrangement according to the present invention can have a mirrored design to work in the opposite direction, i.e. with an external torque acting in an anti-clockwise direction.
The ratchet mechanism housing 17A,17B comprises four (here) pawl locking seats, each of which formed by a lower pawl locking seat part 41A in the ratchet mechanism housing lower part 17A and an upper pawl locking seat part 41B in the ratchet mechanism housing upper part 17B. The purpose of the pawl locking seats is to take up ratchet pawls 8 of the ratchet hub 18 in an engaged, ratchet, mode. In a disengaged, free mode the ratchet pawls are prevented from being taken up in the pawl locking seats as will be further described below.
The ratchet mechanism housing lower part 17A further comprises four equidistantly disposed ratchet control arm engagement cams 54 which are provided on a circumferential edge on top of an inner substantially cylindrical wall in which the lower pawl locking seat parts 41A are located, such that each ratchet control arm engagement cam 54 is located above (in a direction towards the outgoing shaft 11), in a level at the upper end of the lower pawl locking seat part 41A and between two equidistantly and circumferentially disposed lower pawl locking seat parts 41A. The ratchet control arm engagement cams 54 control two spring control arms 4 of the ratchet hub 18.
The ratchet hub 18 is taken up within the ratchet mechanism housing lower and upper parts 17A,17B resting on a lower circumferential edge protruding slightly inwards from the inner wall of the ratchet mechanism housing lower part 17A. The ratchet hub 18 comprises two ratchet pawls 8,8 disposed and protruding on opposite outer cylindrical side walls of the ratchet hub 18 and two spring control arms 4,4 as will be more thoroughly illustrated in
Within a lower peripheral substantially cylindrical wall of the upper hub unit 181B an ingoing shaft socket 182 is provided for taking up the ingoing, motor, shaft 21. Two ratchet hub control arm disengagement cams 55,55 are disposed on and protruding in opposite directions from the outer cylindrical wall of the ingoing shaft socket 182. The ingoing shaft socket 182 is controlled by the motor of the motor unit 23.
In
External torques to which outgoing shaft 11 is exposed will be taken up by the ratchet mechanism arrangement 10 housing via ratchet pawls 8,8, which can be taken up in or released from pawl locking seats 41A,41B in the ratchet mechanism housing lower and upper parts 17A,17B (
Two oppositely directed outwardly facing pawl bearing seats are formed by a respective lower and an upper pawl bearing seat part 42A,42B in the outer wall of the respective lower and upper hub part 181A,181B.
The outgoing shaft 11 can as referred to above be switched between a ratchet mode and free mode.
Thus, external clockwise torque loads on the outgoing shaft 11 are transferred to the ratchet mechanism 10 (housing) via the ratchet pawls 8,8 and the pawl locking seats, hence preventing the outgoing shaft 11 from rotating clockwise and protecting the motor 23 and the gearbox 22 from external torque loads. Thus, the demands on the motor unit (and power supply) and the gearbox are considerably reduced and therefore smaller motors and gearboxes can be used.
The outgoing shaft can still rotate anti-clockwise by running the inner or motor unit shaft 21 anti-clockwise or by external anti-clockwise torque loads.
The inventive concept is applicable irrespectively of type of gear or gear box, there being no particular requirements thereon. The motor may e.g. be a step motor, a brushless DC motor and preferably electrically controllable by means of an electric control unit CU 30 (cf.
It should be clear, however, that the inventive concept also is applicable for other types of motors, or even for manual control and operation.
The ratchet pawls 8,8 are hence spring loaded by the coil springs 6,6 and by the pawl control springs 5,5 which are controlled by spring control arms 4,4 which can be set or arranged to take two different positions, either activating (or engaging) the ratchet pawls 8,8, or disengaging them via the pawl control springs 5,5. In
Elements already discussed with reference to preceding drawings bear the same reference numerals and will not be further discussed here.
By the first and second control cams 47A,48A the position of the spring control cam arm 4 is controlled via the motor unit shaft 11 and the ratchet control mechanism 10.
For switching the outgoing shaft 11 from disengaged, free, mode to engaged, ratchet, mode, the outgoing shaft 11 is moved in relation to the housing of the ratchet control mechanism arrangement 10.
For switching the outgoing shaft 11 from ratchet mode to free mode, the motor shaft 21 is moved in relation to outgoing shaft 11.
In
It should be noted that the holding torque may not exceed the motor unit maximum torque at this operation, otherwise the disengagement of the ratchet pawl 8 will not work.
A change from engaged mode to disengaged or free mode can be activated by means of activating a first disengagement activation means, e.g. comprising a disengagement activation button 32 connected to the control unit 30. When the first, disengagement means 32 are activated, the control unit 30 control the motor unit 23 of the drive unit 20 to run in the first direction until the torque increases, and the ratchet pawls 8,8 will be locked or engaged in the respective pawl locking seats 41A,41B giving a zero angle position defining a starting angular position. With the ratchet pawls 8,8 locked in the respective pawl locking seats 41A,41B, the control unit 30 will run the motor unit 23 or the drive unit 20 with an increased torque to overcome a bias torque produced by the torque position spring 129 arranged in the ratchet hub 18 between the 182 and the lower hub part 181A (see
The control unit 30 will then run the motor 23 in the second direction a second, low, number (N′) of revolutions until the ratchet pawls 8,8 are lifted from the respective pawl locking seats 41A,41B. N may e.g. be a number between 3 and 7, more particularly e.g. 5, although the inventive concept is not limited thereto. N may be somewhat more or less.
The control unit 30 then controls the motor of the motor unit 23 to make a third number (N″) of revolutions, N″ e.g. between 30 and 70, e.g. about 50, with a low speed in the first direction to assure that a correctly performed unlocking or disengagement of the ratchet pawls 8,8 has been achieved. It should be clear that the inventive concept is not limited to any particular number of revolutions N″, but it should be as many as required to make sure that disengagement has been achieved.
The control unit (30) then controls the motor of the motor unit 23 to run in the first direction until the first disengagement activation means, e.g. the disengagement activation button 32, is deactivated.
A change from disengaged, free, mode to engaged mode can be activated by means of activating a second, engagement, activation means, e.g. comprising an engagement activation button 32′ connected to the control unit 30. When the second, engagement, activation means 32′ are activated, the control unit will run the motor unit 23 or the drive unit 20 in the second direction, the ratchet housing control arm disengagement cam 54 moving the spring control arms 4,4 into an engagement mode position.
The control unit (30) will then run the motor of the motor unit 23 in the second direction until the second, engagement, activation means, e.g. the engagement activation button 32′, is deactivated. In alternative embodiments (not shown) the locking, ratcheting elements may be arranged in an inverted manner such that the ratchet pawls are instead arranged in, or rotatably secured to, the housing etc.
Through the use of a ratchet mechanism arrangement 100 according to the invention a small motor pack (comprising motor, gearbox and power supply) can be used to control an outgoing shaft 11 that can be subjected to higher static torque loads than the motor pack can handle.
It is an advantage that, for example for furling systems, the arrangement according to the invention can be used and e.g. replace a worm gear mechanism which only has an efficiency of about 30%, and requires an oversized motor and oversized power supply.
It should be clear that the invention is not limited to the explicitly described embodiments but that it can be varied in a number ways within the scope of the appended claims. The arrangement is particularly intended for use on a boat, particularly a leisure sailing boat, in applications where a maximum expected holding torque higher than a motor unit operation torque, such as in furling systems for mainsails, furling systems for headsails (Jibs and Genoas), for Cod 0 and gennaker furling systems, but also for other systems where similar problems may arise, also in other applications than for furling systems.
It should also be clear that the content of described embodiments freely can be varied and combined.
Number | Date | Country | Kind |
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1951310-0 | Nov 2019 | SE | national |
Filing Document | Filing Date | Country | Kind |
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PCT/SE2020/050880 | 9/21/2020 | WO |