Abstract:
Power generating apparatus includes a float mounted on a support pivotally mounted to a base and secured to a beam extending rearwardly of the base to a vertically extending elongated structure carrying a pair of vertically movable gear racks in guideways. Each rack is engaged by a gear wheel driven by movement of the racks and a one-way drive arrangement connects each gear wheel to an output shaft. Driving weights are secured to each rack to drive the racks in opposite directions under the action of gravity forces acting on the weights, thus causing the output shaft to rotate in a given direction. The free end of the beam is connected to a cross-arm vertically moveable on a guide on the elongate structure, the cross-arm having a motion transmitting arrangement to raise each weight during vertical movement of the cross-arm resulting from movement of the float.

Description:
INTRODUCTION TO THE INVENTION 
   This invention relates to improvements in power generating apparatus and relates particularly to improvements in apparatus for generating power utilizing wave motion in open bodies of water. 
   BACKGROUND TO THE INVENTION 
   A number of proposals have been made for the utilization of wave and/or tidal power for generation of electrical power. Such prior proposals generally include generating apparatus which utilize float means moveable by the wave motion on an open body of water. The movement of the float means is then translated into electrical energy by appropriate mechanical apparatus arranged to drive power generating apparatus. The present invention is directed to an improved form of apparatus based on particular improvements to the disclosure in U.S. Pat. No. 4,249,639 for utilizing the potential energy in water movement, and particularly wave motion, to generate electrical power. 
   OBJECTS OF THE INVENTION 
   It is an object of the invention to provide apparatus which is relatively economical to construct and erect and which is able to utilize the wave motion for electrical power generation, including both vertical and horizontal wave motion. 
   A further object of the present invention is to provide apparatus which is adapted to utilize the motion of all wave forms in the sea or other open bodies of water and to translate the potential energy in such wave motion into electrical power. 
   A still further object of the present invention is to provide apparatus which can utilize wave motion which varies in frequency and amplitude and direction. 
   SUMMARY OF THE INVENTION 
   According to the invention there is provided apparatus for generating electrical power utilizing the motion of waves on an open body of water comprising: 
   (a) an elongate support structure extending vertically upwards from a base relatively fixed with respect to said body of water, 
   (b) guide arrangement on said support structure for at least two vertically moveable gear racks and a vertically moveable cross-arm engaged with each rack, 
   (c) motion transmitting arrangement on the cross-arm to move a first one of said gear racks during upward movement of the cross-arm and to move a second of said gear racks during downward movement of the cross-arm, 
   (d) at least one gear wheel engaged with each gear rack, each gear wheel drivingly connected to a first output shaft through one-way motion transmitting arrangement whereby the motion of each gear rack in one direction only drivingly rotates said output shaft, 
   (e) a first driving mass fixed to said first one of said gear racks to drive the gear rack downward under the action of gravity, 
   (f) a second driving mass secured by a cable passing around a pulley on the support structure to said second of said gear racks to drive the said second gear rack upwardly under the action of gravitational forces on said second mass, 
   (g) a float positioned on said body of water and horizontally spaced from the support structure, said float having a shape and configuration whereby the wave motion causes the float to move vertically relative to said base, 
   (h) a support for said float pivotally mounted to a pivot support fixed relative to said base and between said float and said support structure, 
   (i) a beam pivotally mounted at one end to said pivot support and extending towards said support structure, said beam being adjustably secured to said support for movement therewith in the vertical plane, 
   (j) a connecting arm pivoted at one end to the free end of said beam and extending generally, upwardly therefrom to said cross-arm, whereby vertical movement of said float reciprocating drives said cross-arm vertically on its associated guide, wherein said float includes a plurality of float members supported on an axle for rotation responsive to said wave motion wherein said rotational movement is transmitted to a second output shaft through a one way motion transmitting arrangement, and 
   (k) a device for combining the output of said first and said second output shafts and transmitting same to said flywheel. 
   The invention has for its main object to convert the energy in wave motion to a form which is directly usable to generate power. To this end the apparatus of the invention uses the vertical movement of the float to raise the driving masses towards the top of the support structure means. One driving mass is raised during upward movement of the float and the other driving mass is raised during downward movement of the float. The driving masses descend under the action of gravity and drivingly rotate the output shaft through movement of the associated gear racks, gear wheels and one-way motion transmitting means. In addition, the particular improvements to the apparatus of the current invention utilise the horizontal wave movement where individually mounted float members are mounted for rotation about an axle so as to utilise horizontal movement of wave formations wherein the rotational movement is translated via a float drive shaft to a secondary drive wheel which contributes the horizontal aspect of wave movement into the generation power by the apparatus of the invention. 
   Referring now to the particular improvements and modifications provided in the current apparatus, the support structure  14  is provided with a modified float  12 , comprising a plurality of float members  50  configured for free rotation about a float axis  52 . The independent float members act in the same manner and capacity as the principal float  12  previously described so as to utilise vertical motion of the waves. In addition, the float members can also utilise horizontal movement of the waves by rotating around the float axis  52 . The combined motion of the float is therefore able to utilise all aspects of wave movement to improve the efficiency and generation of electricity over and above that previously described with respect to the prior art apparatus disclosed in U.S. Pat. No. 4,249,639. 
   The plurality of float members  50  are adapted to respond to horizontal wave motion by rotating in either direction, dependent on the motion of the waves. The  20  rotational movement is transmitted via a float drive shaft  56 , along the length of the support structure  14  and beams  17  to a secondary drive wheel  48 . The secondary drive will  48  is connected to a second output shaft  47 . The second output shaft incorporates a one way motion transmitting means so as to translate the clockwise and/or anti-clockwise movement of the float members into a consistent motion of the secondary drive wheel  48 . 
   A secondary drive wheel  48  includes means to transfer the rotational movement to the float wheel  12  by way of a mechanism combining the output forces of the secondary output shaft  47  with the first output shaft  32 . The combined rotational movements of the first and second output shafts act in concert to apply a drive force of float wheel  12  which in turn can be used for the generation of electricity. 
   The mechanicals of the improved apparatus allow for the independent or combined application of vertical and horizontal wave movements into a combination of vertical and rotational movement of the float  12  which in turn can be independently or in combination translated into rotational, mechanical power at the first and second output shafts which finally can be combined for driving the float wheel  12 . 
   A large flywheel is preferably mounted on or connected to the first and second output shafts, and a generator of appropriate power output is driven by suitable drive-belts or gearing from the output shaft. 
   The invention will be more clearly understood from the following description of one embodiment of the apparatus taken in conjunction with the accompanying drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a side elevation of the improved apparatus; 
       FIG. 2  is a plan view of the apparatus drive chain; 
       FIG. 3  is a plan view including the structural elements; 
       FIG. 4  is an end view of the apparatus; 
       FIG. 5  is a side elevational view of the prior art embodiment of the power generating apparatus 
       FIG. 6  is a diagrammatic perspective view of the motion translation portion of the prior art apparatus. 
   

   LEGEND 
   
       
         12 . Float 
         13 . 
         14 . Support structure 
         15 . 
         16 . Pivot 
         17 . Beam 
         18 . Lugs 
         19 . Spacer 
         20 . 
         21 . Support 
         22 . Guide Way 
         23 . Guide Way 
         24 . Rack 
         25 . 
         26 . Rack 
         27 . 
         28 . Gear 
         29 . Shaft 
         30 . 
         31 . Ratchet 
         32 . First output shaft 
         33 . Second gear 
         34 . Second ratchet 
         35 . 
         36 . Fly wheel 
         37 . Cross arm 
         38 . 
         39 . Mass 
         40 . 
         41 . Mass 
         42 . Wire 
         43 . Pillar 
         44 . Connecting arm 
         45 . 
         46 . Primary drive wheel 
         47 . Second output shaft 
         48 . Secondary drive wheel 
         49 . 
         50 . Float members 
         51 . 
         52 . Float axle 
         53 . 
         54 . Float gearbox 
         55 . 
         56 . Float drive shaft 
         57 . 
         58 . Universal joint 
         59 . 
         60 . Transmission belt 
         61 . 
         62 . Frame 
         63 . 
         64 . One way motion transmitting gearbox 
     
  
   DESCRIPTION OF THE PREFERRED EMBODIMENT 
   Referring to the drawings, there is provided power generating apparatus which comprises a float  12  constructed to be positioned on a body of water in a location so as to be subjected to wave motion. The location of the float  12  may be in an ocean adjacent the shore, or adjacent a substantially rigid structure over the water so that relative movement occurs between the float and its support due to wave motion. 
   Preferably, the float  12  is of substantially rectangular or trapezoid shape with an upwardly inclined forward edge portion which extends towards the direction of advance of the prevailing wave motion. The optimum shape, size and weight of the float may be experimentally determined to ensure maximum degree of movement of the float in response to wave movement. 
   The float  12  is mounted on one end of a support structure  14  pivoted at its other end on a pivot support  16  which is immovably fixed to a base mounted either on shore or on a relatively fixed rigid structure. For the purposes of this specification the invention will be described with the apparatus located on land and the float in sea water at a location where wave motion is substantially constant. 
   The wave motion acts on the float  12  to cause vertical movement thereof which results in arcuate movement of the support  14  about the pivot  16 . 
   A beam-like structure  17  extends rearwardly of the pivot support  16  and is adjustably secured to the forwardly extending support structure  14  by means of rigid lugs  18  and spacer bars  19 , shown diagrammatically in  FIG. 1 . With this arrangement, at any particular time, the optimum position of the float  12  in relation to the pivot  16  and the power generating apparatus may be selected. 
   The power generating apparatus which is operated by the vertical movement of the float comprises a vertical elongate support structure  21  immovably fixed in position. The structure  21  carries vertically extending guideways  22  and  23  guiding and supporting a pair of spaced gear racks  24  and  26  which are adapted to move vertically in the respective guideways  22  and  23 . Each gear rack  24  and  26  is engaged by a gear wheel  27  and  28 , mounted for rotation on shafts  32  and  29  on movement of the respective racks. The gear wheel  27  is connected through a ratchet mechanism  31  to the output shaft  32 , and gear wheel  28  drives a second gear  33  which is connected through a second ratchet mechanism  34  to the output shaft  32 . A flywheel  36  mounted on the output shaft  32  drives a generator (not shown) for generation of electrical power on rotation of the fly wheel  36 . 
   Each ratchet mechanism  31  and  34  is arranged so that the movement of the respective racks  24  and  26  in opposite directions will rotate the flywheel  36  and reverse movements of the respective racks will result in slip of the ratchet mechanism. In other words, movement of the rack  24  vertically upwards will cause a driving motion to be transmitted to the flywheel  36  and vertical movement downwards of the other rack  26  will also drive the flywheel  36  in the same direction. 
   Each rack  24  and  26  is moved vertically on its associated guideway by means of a cross-arm  37 , which itself is guided for movement parallel to the gear rack guideways by a suitable guide post  38 . The cross-arm  37  is provided with releasable connecting means which are known per se and not illustrated in detail comprising spring biased wedges, ball detents, ball and ramp wedging means or other suitable releasable connecting means which enables the cross-arm  37  to grip and raise the gear rack  26  when the cross-arm is moved vertically upwards and to release that rack  26  and grip and move the other rack  24  downwards when the cross-arm  37  is moved vertically downwards. 
   It will therefore be seen that the arrangement of the cross-arm and the racks is such that reciprocating vertical movement of the cross-arm moves one rack to an elevated position and moves the other rack to a lowered position on the column. 
   Each gear rack  24  and  26  is connected to a driving mass  39  and  41 , the gear rack  26  which is raised by the cross-arm  37  to the elevated position being directly connected to the mass  41  so that the mass tends to move that rack downwardly, and the other gear rack  24  being connected to the mass  39  via a cord or steel wire  42  passing from the top of the gear rack  24  over a pulley  43  mounted on the top of the support structure. 
   In operation of the apparatus, the cross-arm  37  is connected to the free end of the beam-like structure  17  by means of a connecting arm  44 . 
   As the float  12  is moved vertically by action of waves acting upon it, the free end of the rearwardly extending beam-like structure  17  moves vertically a distance determined by the vertical distance moved by the float  12  and the ratio of the distance between the free end of the structure  17  and the pivot support  16  and the distance between the pivot support  16  and the float  12 . 
   Vertical movement of the end of the structure  17  is transmitted to the cross-arm  37  by the connecting arm  44  so that the cross-arm is also moved vertically along its guide post  38 . 
   Each time the cross-arm  37  is elevated the releasable connecting means engages with the gear rack  26  and moves that rack vertically. At this time the connecting means is automatically released from connection with the other gear rack  24  so the cross-arm  37  simply slides along that rack without imparting a vertical motion thereto. 
   As the cross-arm  37  begins to descend in response to the float  12  being raised by wave motion, the releasable connecting means engages the cross-arm  37  to the gear rack  24  to move that rack vertically downwards, thus raising the mass  39 . At this time, the gear rack  26  is released from connection with the cross-arm  37  and is able to descend along its guideway under the action of the driving mass  41 . 
   Therefore, the operation of the cross-arm  37  is alternately moving one or other gear racks to their uppermost position. When the gear racks are released from connection with the cross-arm  37  the masses act to move the respective racks thereby rotating the associated gear wheels and the fly wheel  36 . 
   The particular improvements provided by the current invention are specifically exemplified with modifications to the float  12  which take the form of a plurality of individual float members  50  formed in a generally circular configuration and linked together for rotation about a pivot point  52 , which takes the form of a float axle. The individual float members are adapted for free movement in either direction about the float axle  52  such that they can be responsive to horizontal wave motions in a clockwise or anticlockwise direction. The rotational movement of the float members  50 , provides the additional dimension of motion, in addition to the vertical motion previously described. The rotational movement of the float members  50  is harnessed by float gearbox  54  which translates the rotational movement to the float drive shaft  56  which is configured to transmit the rotation of movement along the length of the support structure  14  and beam  17  to a one-way motion transmitting gearbox  64 , positioned in proximity to the general frame  62  and support members  21  of the apparatus. The one-way motion transmitting gearbox  64  is configured to transmit the rotational movement of the driveshaft  56  into a one-way motion of the secondary drive wheel  48 , such that the clockwise or anticlockwise movement of the float members  50 , responsive to horizontal movement in waves is transferred to a single rotary action of a secondary drive wheel  48 . In this manner, the secondary drive wheel  48  is able to provide additional energy input into the apparatus for use in conjunction with the energy input provided by a drive wheel  46 . The rotational energy provided by the secondary drive wheel  48  is then transmitted to the fly wheel  36  by way of a suitable arrangement of pulleys or belts. The fly wheel  36  is remotely located from the support  21  and is also fed by a suitable belt or chain transmission from the primary drive wheel  46 . 
   In this manner, the combined vertical and horizontal wave motions can now be fully utilised by all the mechanical aspects of the apparatus and the combined motions fed into the fly wheel  36 , so as to provide the full driving power to fly wheel from all the wave motions available to the apparatus. 
   As previously stated, the fly wheel  36  is connected to an electrical generating system (not shown) to generate electricity as a result of the downwardly moving masses. The vertical and horizontal movement of the waves acting on the floats  12  is thereby converted into electrical energy. 
   The structure of this invention ensures that the fly wheel  36  is not directly driven by motion from the float but is driven by the action of the falling masses associated with each of the moveable racks, and the associated action of the rotating float members. 
   The structure of the invention may be mounted adjacent the shore or, alternatively, may be mounted on a platform erected some distance from the shore in order to take advantage of somewhat larger waves developed in offshore locations. Power from the electrical generators may then be transmitted via undersea cables. 
   It will also be appreciated that a plurality of mechanisms in accordance with the invention may be located close together (or spread over some distance), each generating system operating independently and feeding power into a common electrical grid. 
   It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.