Abstract:
The present invention provides a system and method for converting wave energy into electric energy in an intelligent, practical, and efficient manner. The system utilizes a power input shaft coupled with a vertically reciprocating buoy to rotate a crank gear and a ratchet gear meshing therewith. An intelligent control system is included to monitor, control, and optimize the operations of the system. The length of the power input shaft is adjusted in response to water level fluctuations so that the rotational motion of the crank gear is intelligently controlled within a predetermined desirable region for maximum efficiency.

Description:
CROSS-REFERENCE TO RELATED U.S. APPLICATIONS 
     This application is a CIP application of U.S. application Ser. No. 13/700,471 to Michael Fuquan Lee, filed on Jun. 8, 2011, and titled “Intelligent Control Wave Energy Power Generating System”, which is a 371 of PCT/US11/39532 filed Jun. 8, 2011, which claims priority from U.S. Provisional Patent Application No. 61/397,257 to Michael Fuquan Lee, filed on Jun. 9, 2010, and titled “Wave Energy Power Plant”. The contents of these applications are incorporated herein by reference in their entirety. 
    
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not applicable. 
     NAMES OF PARTIES TO A JOINT RESEARCH AGREEMENT 
     Not applicable. 
     REFERENCE TO AN APPENDIX SUBMITTED ON COMPACT DISC 
     Not applicable. 
     FIELD OF THE INVENTION 
     The present invention generally relates to a power generating system utilizing wave energy. More particularly, the vertical motion of a buoy on waving water is translated into the rotational motion of a crank gear, and the rotational motion is intelligently controlled within a predetermined desirable region. As a result, irregular and variable total or partial vertical motion of the buoy can be successively translated into stable rotational motion in a practical and efficient manner. 
     BACKGROUND OF THE INVENTION 
     Waves are generated by wind passing over the surface of water such as sea. As long as the waves propagate slower than the wind speed just above the waves, there is an energy transfer from the wind to the waves. Waves in oceans and lakes have great potential as an alternative energy source. Wave energy is clean, renewable, and vastly available. The estimated amount of wave energy available in U.S. alone is 2,100 terawatt-hours per year, about one fourth of annual U.S. energy imports. To make wave energy useful, wave energy is transformed into other energy forms, usually electric energy. 
     A wave farm, either offshore or nearshore, is a collection of machines in the same location and used for the generation of wave power electricity. Prior inventions for generating power from waves have provided apparatuses that often include a floating device, a gearing assembly, and an electric generating assembly. The floating device is connected to the gearing assembly such that when waves push the floating device the vertical motion of waves is converted into rotational motion of the gearing assembly. The gearing assembly is connected to the electric generating assembly such that the rotation of the gearing assembly drives the electric generating assembly to generate electric energy. 
     However, these apparatuses usually have three limitations. First, they are too fragile to use in real wave conditions. Wave directions are usually unpredictable. Variations of wave direction will cause unpredictable motion of the gearing assembly, which will result in extra wear and even breakage of the gearing assembly. Second, these apparatuses are inefficient in converting wave energy into electric energy. A substantial energy loss occurs each time the entire floating assembly is uplifted by wave action, leaving less energy for driving the gearing assembly and eventually being converted into electric energy. Also, these apparatuses are designed under the assumption of a fixed wave height and water level, resulting in inefficiency during the times when these assumptions are inevitably incorrect. Third, these apparatuses are prone to damage under severe wave and weather conditions from lack of protective means. Since the floating device is mechanically coupled with the gearing assembly, huge waves may damage the whole apparatus by causing the floating device to collide with the gearing assembly. 
     Therefore, there exists a need for new wave energy power generating system capable of overcoming the aforementioned limitations. Advantageously, the present invention provides a solution that can meet such a need. The intelligent control wave energy power generating system according to the present invention comprises a set of novel devices, assemblies, and an intelligent control system to convert wave energy into electric energy. It provides a method to convert wave energy into electric energy efficiently, safely, and practically under various wave and weather conditions. It also includes a mechanism to protect itself under severe wave and weather conditions. 
     SUMMARY OF THE INVENTION 
     One aspect of the present invention provides a system for wave energy generation for use above a body of waving water. The system can be powered by irregular, unpredictable, and variable wave actions from all directions. The system comprises: 
     a platform assembly above the waving water; 
     a buoy for floating on the waving water; 
     a motion translating assembly coupled with said buoy for translating vertical motion into rotational motion, comprising (i) at least one power input shaft coupled with said buoy at a first coupling position on said power input shaft and (ii) a gear transmission assembly having at least one crank gear coupled with said power input shaft by coupling a second coupling position on said power input shaft to a third coupling position on said crank gear; wherein said third coupling position on the crank gear is driven to rotate reciprocally within an angle θ of less than 180 degrees as the buoy is moved up and down by the waving water; 
     an adjustor that can be activated to vary the distance between the first coupling position and the second coupling position when the angle δ between the bisector of angle θ and the horizontal plane is not zero so that the absolute value of angle δ is decreased (for example, δ may be close to zero or equal to zero); and 
     a plurality of generators coupled with said gear transmission assembly and stationed on said platform assembly such that rotational motion within said gear transmission assembly results in said generators generating electric energy. 
     In exemplary embodiments, the system further comprises an intelligent control system connected with said motion translating assembly, said adjustor, and said plurality of generators for collecting and processing information of environmental and said system&#39;s conditions from a plurality of sensors and meters, determining directives, and transmitting directives. For example, when the angle δ between the bisector of angle θ and the horizontal plane is measured as not being zero, the intelligent control system may automatically activate the adjustor to vary the distance between the first coupling position and the second coupling position, and therefore to decrease the absolute value of angle δ to a lower value including near-zero or zero. 
     The above features and advantages and other features and advantages of the present invention are readily apparent from the following detailed description of the best modes for carrying out the invention when taken in connection with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       The present invention is illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings and in which like reference numerals refer to similar elements. All the figures are schematic and generally only show parts which are necessary in order to elucidate the invention. For simplicity and clarity of illustration, elements shown in the figures and discussed below have not necessarily been drawn to scale. Well-known structures and devices are shown in simplified form in order to avoid unnecessarily obscuring the present invention. Other parts may be omitted or merely suggested. 
         FIG. 1A  schematically depicts a wave energy power generating system in accordance with an exemplary embodiment of the present invention; 
         FIG. 1B  schematically depicts a control mechanism of the rotational motion of a crank gear within a predetermined desirable region in the system of  FIG. 1A  in accordance with an exemplary embodiment of the present invention; 
         FIG. 1C  depicts an embodiment of an intelligent control wave energy power generating system without its cover in accordance with the present invention; 
         FIG. 2  is a side schematic section view of the intelligent control wave energy power generating system in  FIG. 1C ; 
         FIG. 3  is a top schematic view of the intelligent control wave energy power generating system in  FIG. 1C ; 
         FIG. 4  is a schematic section view of an embodiment of a threaded rod adjustment device in accordance with the present invention; 
         FIG. 5  is a schematic section view of an embodiment of a flexible pivot device in accordance with the present invention; 
         FIG. 6  is a schematic view of a generator assembly of the intelligent control wave energy power generating system in  FIG. 1C ; 
         FIG. 7A  is a schematic view of an embodiment of a counterbalancing and maintenance device in accordance with the present invention; 
         FIG. 7B  is another schematic view of an embodiment of a counterbalancing and maintenance device in accordance with the present invention; 
         FIG. 8  is a schematic view of an embodiment of a power plant with ten intelligent control wave energy power generating systems in accordance with the present invention; 
         FIG. 9  is a schematic illustration of a control mechanism of the intelligent control wave energy power generating system in  FIG. 1C ; 
         FIG. 10  is a schematic illustration demonstrating the operations of a power input shaft, a threaded rod adjustment device, and a crank gear, of the intelligent control wave energy power generating system in  FIG. 1C ; and 
         FIG. 11  is a schematic view depicting the operations of an intelligent control system of the intelligent control wave energy power generating system in  FIG. 1C  in severe wave and weather conditions. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     In the following description, for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It is apparent, however, to one skilled in the art that the present invention may be practiced without these specific details or with an equivalent arrangement. Embodiments of the present invention are described herein with reference to illustrations of idealized embodiments. As such, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. There is no intent to limit the principles of the present invention to the particular disclosed embodiments. For example, in the drawings, the size and relative sizes of layers and regions may be exaggerated for clarity. In addition, embodiments of the present invention should not be construed as limited to the particular shapes of regions illustrated herein but are to include deviations in shapes that result, for example, from manufacturing. For example, a region illustrated as a rectangle may have rounded or curved features. Thus, the regions illustrated in the figures are schematic in nature and their shapes are not intended to illustrate the precise shape of a region of a device or of topography and are not intended to limit the scope of the present invention. 
     Where a numerical range is disclosed herein, unless otherwise specified, such range is continuous, inclusive of both the minimum and maximum values of the range as well as every value between such minimum and maximum values. Still further, where a range refers to integers, only the integers from the minimum value to and including the maximum value of such range are included. In addition, where multiple ranges are provided to describe a feature or characteristic, such ranges can be combined. That is to say that, unless otherwise indicated, all ranges disclosed herein are to be understood to encompass any and all subranges subsumed therein. For example, a stated range of from “1 to 10” should be considered to include any and all subranges between the minimum value of 1 and the maximum value of 10. Exemplary subranges of the range 1 to 10 include, but are not limited to, 1 to 6.1, 3.5 to 7.8, and 5.5 to 10. Further, where an integer range of from “0 to 12” is provided, it will also be considered to include any and all subranges as described above. 
     Referring the system for wave energy generation in  FIG. 1A , a platform assembly  1100  is built above a body of waving water  1000  such as ocean, lake and river. A buoy  1200  is floating on the waving water, and is moved up and down (i.e. vertical motion) by the wave actions. A motion translating assembly  1300  is coupled with buoy  1200  for translating a vertical motion into a rotational motion. Assembly  1300  includes at least one power input shaft  1310  (typically rigid) coupled with buoy  1200  at a first coupling position labeled as x on shaft  1310 . Assembly  1300  also includes a gear transmission assembly  1350  having at least one crank gear  1351 . Crank gear  1351  is coupled with power input shaft  1310  for translating a vertical motion into a rotational motion. Specifically, a second coupling position labeled as y on shaft  1310  can be coupled in any manner with a third coupling position labeled as C on crank gear  1351 . The spatial relationship between point y and point C may be variable or invariable. Positions y and C may be two separate positions, or they may be merged into one position. While position C is fixed on, or invariable relative to, crank gear  1351 , position x and/or y are/is not fixed on shaft  1310 , and may keep changing along shaft  1310 , resulting in the variation of the distance between x and y in a controlled manner. As buoy  1200  is moved up and down by the waving water, it drives shaft  1310  up and down as well. As a result, third coupling position C on crank gear  1351  is driven to rotate around the rotational axis O of crank gear  1351 . 
     Referring to  FIG. 1B  for more details, point C rotates between radial line Op and radial line Oq. When position C reaches radial line Op and becomes a point thereof, C cannot move up (or move clockwise) any further, and can only move back (or move counterclockwise) toward radial line Oq. When C reaches radial line Oq and becomes a point thereof, C cannot move down (or move counterclockwise) anymore, and must move back (or move clockwise) toward radial line Op. Angle θ is defined as the angle ∠pOq, wherein O is the vertex of the angle, and Op and Oq are two sides of the angle. We say the third coupling position C on crank gear  1351  rotates reciprocally within an angle θ, which may be less than 180 degrees (180°), for example less than 170°, less than 160°, less than 150°, less than 140°, less than 130°, less than 120°, and so on and on. However, it should be appreciated that when θ=0, the water is completely calm, there is no wave action at all, and both the buoy and then crank gear are still or stationary. When θ is too close to 180°, the risk of damage the system is high. However, when θ is too close to zero, the energy output may not be as high as desired. 
     Radial line Or is the interior or internal bisector of angle θ, and it passes through the apex O of angle θ and divides it into two angles with equal measures θ/2. Angle δ is defined as the angle between the bisector Or and the horizontal plane (denoted as HP). A plane is said to be horizontal at the location where the buoy  1200  sits if it is perpendicular to the gradient of the gravity field at that location. Pick the horizontal plane that contains point O, or at the height of O. The normal vector of the HP that passes through O and the line Or together define a plane perpendicular to the HP within which the angle δ is formed between the bisector Or and the HP. The angle δ is further defined as negative when the bisector Or is below the horizontal plane as shown in  FIG. 1B , and δ may range in theory from 0 down to −90°, but preferably it ranges from 0 to −85°, and more preferably from 0 to −80°. Angle δ is defined as positive when the bisector Or is above the horizontal plane (opposite to what is shown in  FIG. 1B ), and δ may range in theory from 0 down to 90°, but preferably it ranges from 0 to 85°, and more preferably from 0 to 80°. 
     Referring back to  FIG. 1A , an adjustor  1400  can be activated to vary the distance between the first coupling position x and the second coupling position y on shaft  1310  (hereinafter “distance xy”), when angle δ is measured as not being zero. One purpose of varying distance xy is to decrease the absolute value of angle δ. For example, when angle δ is measured as being −10°, adjustor  1400  can be activated to increase distance xy so that angle δ is decreased to a lower absolute value such as −9°, −8°, −7°, −6°, −5°, −4°, −3°, −2°, −1°, 0°, 1°, 2°, 3°, 4°, 5°, 6°, 7°, 8°, and 9°. Preferably, angle δ is decreased to a value with the same positive/negative sign as δ initially had before it started to decrease, such as −9°, −8°, −7°, −6°, −5°, −4°, −3°, −2°, −1°, and 0°. When angle δ is measured as being +10°, adjustor  1400  can be activated to decrease distance xy so that angle δ is decreased to a lower absolute value such as 9°, 8°, 7°, 6°, 5°, 4°, 3°, 2°, 1°, 0°, −1°, −2°, −3°, −4°, −5°, −6°, −7°, −8°, and −9°. Preferably, angle δ is decreased to a value with same positive/negative sign in a similar manner as described above, such as +9°, +8°, +7°, +6°, +5°, +4°, +3°, +2°, +1°, and 0°. In preferred embodiments, the absolute value of angle δ should be deceased as close to zero as possible. The smaller the absolute value of angle δ, the better. Varying distance xy can be accomplished by changing the first coupling position x on shaft  1310 , and/or changing the second coupling position y on shaft  1310 . In a preferred embodiment, varying distance xy is accomplished by changing the second coupling position y on shaft  1310  only. 
     In various embodiments, adjustor  1400  may be activated to vary the distance between the first coupling position and the second coupling position (distance xy) when the angle δ between the bisector of angle θ and the horizontal plane is greater than 5°, greater than 10°, or greater than 15°, for example. 
     Angle δ may be detected at a frequency of F1, and distance xy can be adjusted accordingly at a frequency of F2. F1 may be for example once every one minute, once every two minutes, once every three minutes, once every four minutes, once every five minutes, and so on and on. Depending on the value of angle δ detected, F2 may be controlled to be same as F1 (F2=F1) or different than F1 (F2≠F1). In an embodiment, F2=αF1, and α is in the range of from 0.2 to 0.5. For example, F2=F½ (half), F2=F⅓ (one third), F2=F¼ (one fourth), and so on and so forth. F2=F½ means that, for example, F1 is once every one minute, and F2 is once every two minutes. 
     Referring back to  FIG. 1A , a plurality of generators  1500  are stationed on platform assembly  1100 , and coupled with gear transmission assembly  1300 . The rotational motion within gear transmission assembly  1300  can drive the generators  1500  to generate electric energy. As a result, the system can be powered by irregular, unpredictable, and variable wave actions from all directions. 
     In preferred embodiments, the power generating system of the invention further comprises an intelligent control system  1600  that is connected to motion translating assembly  1300 , adjustor  1400 , and plurality of generators  1500  for collecting and processing information of environmental and said system&#39;s conditions from a plurality of sensors and meters (not shown), determining directives, and transmitting directives. 
     The present invention provides an intelligent control wave energy power generating system for converting wave energy into electric energy. In accordance with one embodiment, the intelligent control wave energy power generating system comprises (1) a buoy, (2) a platform assembly, (3) a motion translating assembly, (4) a threaded rod adjustment device, as an example of adjustor  1400 , (5) a generator assembly, (6) a counterbalancing and maintenance device, (7) an intelligent control system, and (8) an openable cover. 
     The buoy floats on the water surface, and is coupled with a power input shaft in the motion translating assembly. The motion translating assembly also includes a gear transmission assembly coupled with the power input shaft to convert the vertical motion of the buoy via the power input shaft into the rotational motion of gears and a driveshaft. When the buoy reciprocates vertically in response to wave action, the driveshaft rotates and drives generators in the generator assembly to produce electric energy. The platform assembly is piled into the ocean or lake floor to support the rest of the system. 
     The threaded rod adjustment device raises or lowers a threaded rod, which constitutes the top part of the power input shaft, so that the buoy&#39;s vertical movement is within a predetermined range that allows the motion translating assembly to work properly and efficiently. When the water level rises due to daily tides, the threaded rod adjustment device, controlled by the intelligent control system, raises the threaded rod. Similarly, when the water level falls, the threaded rod adjustment device lowers the threaded rod, Because of the irregularity of wave directions, the waves may push the buoy in any horizontal direction, impacting the power input shaft coupled therewith. The motion translating assembly may also include a flexible pivot device connecting the power input shaft and the gear transmission assembly. The flexible pivot device absorbs any impact caused by wave-motion irregularity. This prevents the power input shaft from breaking and the gears in the gear transmission assembly from disengaging. 
     The counterbalancing and maintenance device is coupled with the buoy via a cable to improve the energy conversion efficiency and provide system protection under severe wave and weather conditions. It includes a counterweight that reciprocates vertically in the opposite direction of the buoy. When the waves uplift the buoy, they only need to overcome the weight difference between the buoy and the counterweight. Since the weight of the counterweight is slightly less than that of the buoy, energy lost in raising the buoy can be substantially reduced and more wave energy will be utilized for producing electric energy. The counterbalancing and maintenance device also includes an electric winch assembly and a counterweight lock. Under severe wave and weather conditions, the counterweight lock secures the counterweight and the electric winch assembly pulls the buoy up to a predetermined safe position. 
     The intelligent control system includes a plurality of sensors and meters and a control center. The sensors and meters collect operational information of the intelligent control wave energy power generating system (including e.g. angle δ) and the environmental condition, and send that information to the control center. The control center continuously monitors the condition of the intelligent control wave energy power generating system (including e.g. angle δ) and adjusts the system if necessary, for example, varying distance xy as described above. 
     In the following description,  FIGS. 1C-11  show more specific, but still exemplary, embodiments of the invention in light of the concepts as shown in  FIGS. 1A and 1B . Reference numerals appeared in  FIGS. 1C-11  represent the following components:  10  intelligent control wave energy power generating system;  21  buoy;  30  motion translating assembly;  31  power input shaft;  311  threaded rod;  312  coupling;  313  connecting rod;  32  flexible pivot device;  321  flexible joint;  321 A first flexible joint;  321 B second flexible joint;  322  flexible joint housing;  323  bushing;  324  cover plate;  325  bearing;  326  washer;  327  pivot pin;  33  gear transmission assembly;  331  crank gear;  332  ratchet gear;  333  driveshaft;  334  pulley;  335  flywheel;  34  crank gear pedestal;  35  driveshaft pedestal;  40  threaded rod adjustment device;  41  motor;  42  adjustment device housing;  43  gear shaft;  44  drive gear;  45  threaded driven gear;  46  thrust bearing;  50  generator assembly;  51  generator;  52  clutch pulley;  521  clutch;  53  belt;  60  counterbalancing and maintenance device;  61  cable;  62  counterweight;  63  counterweight lock;  64  electric winch assembly;  641  winch motor;  642  gearbox;  643  winch spool;  644  movable pulley;  645  fixed pulley;  65  counterweight pedestal;  70  intelligent control system;  71  unit control center;  72  group control center;  73  anemoscope;  74  speed sensor;  75  position sensor;  76  wattmeter;  80  platform assembly;  81  rack;  82  mounting bracket;  83  base column;  84  mounting platform;  85  connecting rod insulating cover;  86  cable insulating cover; and  90  openable cover. 
     The present invention provides an intelligent control wave energy power generating system  10  which generates electric energy from waves. One embodiment of the intelligent control wave energy power generating system  10  comprises a buoy or float  21 , a motion translating assembly  30 , a threaded rod adjustment device  40 , a generator assembly  50 , a counterbalancing and maintenance device  60 , an intelligent control system  70 , a platform assembly  80 , and an openable cover  90 . 
       FIG. 1C  shows the intelligent control wave energy power generating system  10  without the openable cover  90 . The buoy or float  21  floats on water surface. The buoy  21  is connected to the motion translating assembly  30 . The motion translating assembly  30  includes a driveshaft  333  coupled with the generator assembly  50 . When the buoy  21  reciprocates vertically in response to wave actions, the motion translating assembly  30  converts the vertical motion of the buoy  21  into the rotational motion of the driveshaft  333 , driving the generator assembly  50  to generate electric energy. 
     The counterbalancing and maintenance device  60  is coupled to the buoy  21 . In normal operation, the counterbalancing and maintenance device  60  reduces the weight the waves have to uplift, so more wave energy is used for generating electric energy. Under severe wave and weather conditions, the counterbalancing and maintenance device  60  pulls the buoy  21  up to a safe position. 
       FIG. 2  shows the buoy  21 , the platform assembly  80 , and the motion translating assembly  30 . The platform assembly  80  comprises a rack  81 , a mounting bracket  82 , a base column  83 , a mounting platform  84 , a connecting rod insulation cover  85 , and a cable insulation cover  86 . The buoy  21  is connected to the base column  83  through the rack  81  and the mounting bracket  82 . The base column  83  is permanently moored into the seabed or lakebed. The connection between the rack  81  and the mounting bracket  82  should be such that the buoy  21  can move up and down with the waves, for example, a double row sealed ball bearing. The mounting platform  84  is fastened to the base column  83  through the mounting bracket  82 . 
     The motion translating assembly  30  comprises a gear transmission assembly  33  and a plurality of power input shafts  31 , flexible pivot assemblies  32 , crank gear pedestals  34 , and driveshaft pedestals  35 . 
     The buoy  21  is coupled with the power input shaft  31  through the rack  81 , and the coupling position on the shaft  31  is an example of position x as shown in  FIGS. 1A and 1B . In this example, position x on shaft  31  is fixed, but it can be adjustable on shaft as well. When the buoy  21  reciprocates vertically in response to wave actions, the power input shaft  31  moves vertically with the buoy  21 . The power input shaft drives the gear transmission assembly  33  through the flexible pivot device  32 . 
     As shown in  FIG. 2 , the power input shaft  31  comprises a threaded rod  311 , a coupling  312 , and a connecting rod  313 . The threaded rod  311  is connected to the connecting rod  313  through the coupling  312 , and the connecting rod  313  is coupled with the rack  81  to establish the connection between the buoy  21  and the threaded rod  311 . The connection between the power input shaft  31  and the rack  81  is also shown in  FIG. 1C . 
     As shown in  FIG. 2 , the gear transmission assembly  33  comprises a driveshaft  333  and a plurality of crank gears  331 , ratchet gears  332 , pulleys  334 , and flywheels  335 . The flexible pivot device  32  connects the threaded rod  311  and the crank gear  331 . In this embodiment, flexible pivot device  32  connects to the threaded rod  311  at position y (see  FIG. 4 ) on shaft  31 , and it connects to the crank gear  331  at position C (see  FIG. 5 ) on crank gear  331 , y and C being shown and explained in  FIGS. 1A and 1B . The crank gear  331  is engaged with the ratchet gear  332 . The ratchet gear  332 , the flywheel  335 , and the pulley  334  are mounted on the driveshaft  333 . The pulley  334  is coupled with the generator assembly  50 . The vertical motion of the power input shaft  31  rotates the crank gear  331 , which drives the ratchet gear  332  to eventually turn the driveshaft  333 . The ratchet gear  332  ensures that the driveshaft  333  rotates in one direction. The flywheel  335  keeps the driveshaft  333  rotating smoothly and uniformly. The driveshaft  333  then rotates the pulley  334 , driving the generator assembly  50  to generate electric energy. 
     The crank gear  331  is moored to the mounting platform  84  through the crank gear pedestal  34 . The driveshaft  333  is moored to the mounting platform  84  through the driveshaft pedestal  35 . 
     As shown in  FIG. 1C , the mounting platform  84  supports the motion translating assembly  30 , the generator assembly  50 , the counterbalancing and maintenance mechanism  60 , and the intelligent control system  70 , which are all mounted on the mounting platform  84 . All parts are above water except the buoy  21  that floats on water surface. 
       FIG. 3  shows one possible embodiment of the motion translating assembly  30 , which comprises two power input shafts  31 , two flexible pivot assemblies  32 , two crank gear pedestals  34 , six driveshaft pedestals  35 , and the gear transmission assembly  33 , which comprises two crank gears  331 , two ratchet gears  332 , two pulleys  334 , three flywheels  335 , and the driveshaft  333 . 
     One power input shaft  31 , one flexible pivot device  32 , one crank gear  331 , one ratchet gear  332 , and one crank gear pedestal  34  are disposed on each side of the balance and maintenance mechanism  60 , which is in the middle of the mounting platform  84 . On each side, the power input shaft  31  is connected to the crank gear  331  through the flexible pivot device  32 . The crank gear  331  is coupled with the ratchet gear  332 , and moored to the mounting platform  84  through the crank gear pedestal  34 . The flywheels  335 , the ratchet gears  332 , and the pulleys  334  are mounted on the driveshaft  333 , which is moored to the mounting platform  84  through the six driveshaft pedestals  35 . One flywheel  335  is placed in the middle of the driveshaft  333  and between the two ratchet gears  332 . The other two flywheels  335  are placed equidistantly from the middle flywheel  335 , one in each half of the driveshaft  333 . One pulley  334  is placed on each end of the driveshaft  333 . This placement keeps the load balanced for the driveshaft  333  and the mounting platform  84 . Other embodiments are possible, for example, with one or two flywheels  335 , or with two or four driveshaft pedestals  35 . 
       FIG. 4  shows one embodiment of the threaded rod adjustment device  40 , as an example of adjustor  1400  in  FIG. 1A . The threaded rod adjustment device  40  is mounted on the threaded rod  311 . The threaded rod adjustment device  40  comprises a motor  41 , an adjustment device housing  42 , a gear shaft  43 , a drive gear  44 , a threaded driven gear  45 , and a thrust bearing  46 . The gear shaft  43 , the drive gear  44 , the threaded driven gear  45 , and the thrust bearing  46  are housed inside the adjustment device housing  42 . Although any point on the fragment of shaft  31  or rod  311  that is housed within the housing  42  can be viewed as position y, the point on the upper terminal point of the fragment P 1 , middle point of the fragment P 2 , or the lower terminal point of the fragment P 3  can be conveniently defined or viewed as position y, for the purpose of defining distance xy. Because it is the amount of distance xy variation that determines the amount of angle δ variation, viewing/defining P 1 , P 2 , P 3  or any other suitable point as position y is not critical for purpose of calculating the change of distance xy. The motor  41  is mounted on top of the adjustment device housing  42 . The motor  41  is coupled with the gear shaft  43 . The drive gear  44  is mounted on the gear shaft  43  and is meshed with the threaded driven gear  45 . The threaded driven gear  45  is meshed with the threaded rod  311 . The threaded driven gear  45  is connected to the thrust bearing  46 . The motor  41  drives the gear shaft  43 , rotating the drive gear  44 , and thus rotating the threaded driven gear  45 . The rotation of threaded driven gear  45  then raises or lowers the threaded rod  311 , and thereby varies the position y on the shaft  31  or rod  311 , and increases or decreases distance xy as shown in  FIGS. 1A and 1B . The thrust bearing  46  maintain the position of the threaded driven gear  45 . 
       FIG. 5  shows the flexible pivot device  32 . The flexible pivot device  32  comprises two flexible joints  321 A,  321 B and a flexible joint housing  322 . The first flexible joint  321 A is housed in the flexible joint housing  322  and mounted on the crank gear  331  at position Pc of crack gear  331  (position Pc being an example of position C on crank gear  1351  in  FIGS. 1A and 1B ). Position Pc can be defined as the central point of the open space (a hole) in the crank gear  331  that accommodates or receives pivot pin  327  of joint  321 A. The first flexible joint  321 A translates the vertical motion of the threaded rod  311  into rotary motion of the crank gear  331 . The second flexible joint  321 B is mounted on the flexible joint housing  322 , and is housed in the adjustment device housing  42 , thus connecting to the threaded rod adjustment device  40 . The second flexible joint  321 B is connected to the threaded rod  311  through the threaded rod adjustment device  40 . 
     Each flexible joint  321  comprises a bushing  323 , a cover plate  324 , a bearing  325 , a washer  326 , and a pivot pin  327 . The bushing  323 , the cover plate  324 , the bearing  325 , and the washer  326  are centered through the pivot pin  327 . The pivot pin  327  of the flexible joint  321 A is fastened on the crank gear  331 . The pivot pin  327  of the flexible joint  321 B is fastened on the flexible joint housing  322 . The first flexible joint  321 A can rotate relative to the crank gear  331 . The second flexible joint  321 B can rotate relative to the flexible joint housing  322 . The two flexible joints  321 A,  321 B may be perpendicular to each other. 
     The flexible pivot device  32  connects the threaded rod  311  to the crank gear  331 . The threaded rod  311  turns the crank gear  331  through the flexible pivot device  32 . Since the two flexible joints  321 A,  321 B are perpendicular to each other, the threaded rod  311  can turn at any angle along x-axis and y-axis without damaging the flexible pivot device  32  or the crank gear  331 . 
       FIG. 6  shows the generator assembly  50 . The generator assembly  50  comprises a plurality of generators  51 , clutch pulleys  52 , and belts  53 . The clutch pulley  52  includes a clutch  521 . The generator  51  is connected to the clutch pulley  52  which is coupled with the pulley  334  through the belt  53 . The generator can be activated or deactivated by engaging or disengaging the clutch  521  in the clutch pulley  52 . The power ratings of the generators  51  are predetermined such that their various combinations span a wide range of power output for various wave conditions. 
     One embodiment of the generator assembly  50  is shown in  FIG. 3 . The generator assembly  50  comprises four generators  51 , four clutch pulleys  52 , and four belts  53 . Two generators  51 , two clutch pulleys  52 , and two belts  53  are coupled with the pulley  334  at each end of the driveshaft  333 . Other embodiments are possible, e.g., using two generators  51 , two clutch pulleys  52 , and two belts  53 . 
       FIGS. 7A and 7B  show one embodiment of the counterbalancing and maintenance device  60 . As shown in  FIG. 7A , the counterbalancing and maintenance device  60  comprises a cable  61 , a counterweight  62 , a counterweight lock  63 , an electric winch assembly  64 , and a counterweight pedestal  65 . As shown in  FIG. 7B , the electric winch assembly  64  comprises a winch motor  641 , a gearbox  642 , a winch spool  643 , a movable pulley  644 , and a plurality of fixed pulleys  645 . The cable  61  is connected to the buoy  21  on one end and tied to the winch spool  643  on the other end. The cable  61  winds through the fixed pulleys  645  and the movable pulley  644 . The counterweight  62  is fastened to the movable pulley  644 . The counterweight lock  63  and the electric winch assembly  64  are mounted on the counterweight pedestal  65 . The winch motor  641  is coupled with the gearbox  642  which is coupled with the winch spool  643 . The winch motor  641  drives the gearbox  642  to spin the winch spool  643 . The winch spool  643  spins to tighten or loosen the cable  61 , moving up or down the buoy  21 , respectively. 
       FIG. 3  shows one embodiment of the intelligent control system  70 . The intelligent control system  70  comprises a unit control center  71 , a group control center  72 , an anemoscope  73 , a speed sensor  74 , two position sensors  75 , and four wattmeters  76 . The anemoscope  73  is mounted on the mounting bracket  82 . The speed sensor  74  is disposed next to the middle flying wheel  335 . The position sensors  75  are disposed next to the crank gears  331  and one position sensor  75  is used for one crank gear  331 . The wattmeters  76  are linked to the generators  51 , and one wattmeter  76  is used for one generator  51 . The sensors and meters, comprising of the anemoscope  73 , the speed sensor  74 , the two position sensors  75 , and the four wattmeters  76 , are linked to the unit control center  71 . The unit control center  71  is linked to the group control center  72 . The intelligent control system  70  is mounted on the mounting platform  84 . The link between the wattmeters  76  and the generators  51 , the links between the sensors and meters and unit control center  71 , and the link between the unit control center  71  and the group control center  72  are not shown in  FIG. 3 . 
     As shown in  FIG. 2 , the part of the connecting rod  313  below the mounting platform  84  is protected by an anti-corrosion connecting rod insulating cover  85 . The part of the cable  61 , which is not shown in  FIG. 2 , below the mounting platform  84  is also protected by an anti-corrosion cable insulating cover  86 . The buoy  21 , the connecting rod  313 , the rack  81 , the mounting bracket  82 , and the bottom side of the mounting platform  84  are made of anti-corrosion materials, or their surfaces have been subject to anti-corrosion treatment. 
     The intelligent control wave energy power generating system  10  can be multiplied and assembled to form a power plant. The power plant may comprise one or multiple independent intelligent control wave energy power generating systems  10 . The number of the intelligent control wave energy power generating systems  10  in the power plant is dependent on the wave condition and expected power output. 
       FIG. 8  shows an embodiment of the power plant with ten intelligent control wave energy power generating systems  10 . Other embodiments are possible, for example, with one or one hundred intelligent control wave energy power generating systems  10 . As shown in  FIG. 8 , each intelligent control wave energy power generating system  10  has an openable anti-corrosion cover  90 . 
     The control mechanism of the power plant is illustrated in  FIG. 9 . The group control center  72  coordinates and controls the unit control center  71 . The unit control center  71  controls the anemoscope  73 , the speed sensor  74 , the position sensor  75  (for e.g. measuring angle θ and angle δ), the wattmeters  76 , the motor  41  (for e.g. varying distance xy), the clutches  521 , the winch motor  641 , and the counterweight lock  63 . When there is only one intelligent control wave energy power generating system  10  in the power plant, the group control center  72  may be removed. When there are two or more intelligent control wave energy power generating systems  10  in the power plant, the group control centers  72  of the intelligent control wave energy power generating systems  10  are connected. 
     Normal Operation: As shown in  FIG. 1 , in the normal operation of the intelligent control wave energy power generating system  10 , the motion translating assembly  30  converts the vertical motion of the buoy  21 , produced in response to wave actions, into the rotational motion of the driveshaft  333 . The driveshaft  333  drives the generator  51  to generate electric energy, which is sent ashore. 
     Motion Translation: 
     As shown in  FIG. 2 , when the waves rise, uplifting the buoy  21  and the threaded rod  311 , the threaded rod  311  turns the crank gear  331  upward through the flexible pivot device  32  such that the vertical motion of the threaded rod  311  is converted into the rotary motion of the crank gear  331 . The crank gear  331  rotates the ratchet gear  332 , which drives the driveshaft  333 . The driveshaft  333  rotates the pulley  334  and the flywheel  335 . As shown in  FIG. 6 , the pulley  334  drives the clutch pulley  52  through the belt  53 . The clutch pulley  52  drives the generator  51  to generate electric energy. 
     As shown in  FIG. 2 , when the waves recede, dropping the buoy  21  and the threaded rod  311 , the flexible pivot device  32  again converts the vertical motion of the threaded rod  311  into the rotary motion of the crank gear  331 , turning the crank gear  331  downward. However, the ratchet gear  332  is not engaged and does not rotate with the crank gear  331 . Therefore, when the waves recede, the driveshaft  333  continues to rotate in the same direction, because of momentum and the torque of the flywheel  335 . In other words, the driveshaft  333  always rotates in one direction and keeps driving the generator assembly  50  to continuously produce electric energy. 
     In summary, the rise and fall of the waves causes the buoy  21  and the threaded rod  311  to move up and down, resulting in the rotary reciprocation of the crank gear  331 . The ratchet gear  332  converts the rotary reciprocation of the crank gear  331  into the rotational motion of the driveshaft  333 , which drives the generator  51  to generate electric energy. 
     As shown in  FIG. 2 , when the waves rise, the threaded rod  311  rotates the crank gear  331  clockwise through the flexible pivot device  32 . The crank gear  331  drives the ratchet gear  332  to rotate counterclockwise. The ratchet gear  332  drives the driveshaft  333  and the flywheel  335  to rotate in the same direction, that is, counterclockwise. When the waves recede, dropping the buoy  21  and the threaded rod  311 , the threaded rod  311  rotates the crank gear  331  counterclockwise. However, the ratchet gear  332  prevents the driveshaft  333  from rotating with the crank gear  331 . The driveshaft  333  continues to rotate counterclockwise because of its momentum and the torque of the flywheel  335 . Therefore, the driveshaft  333  always rotates counterclockwise. 
     As shown in  FIG. 10 , in normal operation, the crank gear  331  rotates reciprocally between two positions: a high position A and a low position B. The angle formed between A and B around the rotational axis o of crank gear  331  is an example of angle θ or ∠pOq in  FIG. 1B . The crank gear  331  reaches the high position A at the peak of the waves. The crank gear  331  reaches the low position B at the trough of the waves. The position of the crank gear  331  can be defined by the position Pc on crank gear  331  as shown in  FIG. 5 . If nine o&#39;clock and three o&#39;clock are viewed as parallel to horizontal plane (HP) as shown in  FIG. 1B , the high position A in  FIG. 10  shows the position Pc at eleven thirty o&#39;clock, and the low position B shows the position Pc at six thirty o&#39;clock. There is also a middle position M where the position Pc is at nine o&#39;clock when the buoy  21  is at the water level. In this case, θ=150° with a bisector parallel to horizontal plane (HP), therefore δ=0, representing an optimized operational condition. In the remaining part of the detailed description, we will use the position Pc to indicate the position of the crank gear  331 . For example, when we say the crank gear  331  is at nine o&#39;clock, it means that the position Pc thereon is at nine o&#39;clock. 
     As shown in  FIG. 5 , in addition to converting the vertical motion of the threaded rod  311  into the rotary reciprocation of the crank gear  331 , the flexible pivot device  32  also converts the horizontal motion of the threaded rod  311  into the rotational motion of the flexible joints  321 A,  321 B. The first flexible joint  321 A can rotate relative to the crank gear  331 . The second flexible joint  321 B can rotate relative to the first flexible joint  321 A. The two flexible joints  321 A and  321 B are perpendicular to each other. Together they allow the threaded rod  311  to turn at any angle along x-axis and y-axis without damaging the flexible pivot device  32  or the crank gear  331 . Since the wave directions are unpredictable, they can cause the threaded rod  311  to turn at an arbitrary angle along x-axis and y-axis. The flexible pivot device  32  accommodates such horizontal motion of the threaded rod  311 . 
     Counterbalancing: 
     As shown in  FIG. 11 , the counterweight  62  moves up and down in the opposite direction of the buoy  21 . The counterweight  62  is slightly lighter than the lifting load, which comprises the parts the waves have to uplift, including the buoy  21 , the power input shaft  31 , the threaded rod adjustment device  40 , and the flexible pivot device  32 . When the waves push the lifting load up, the counterweight  62  moves down, thus reducing the weight the waves have to uplift. With the counterweight  62 , the waves can push the buoy  21  and the power input shaft  31  higher, turning the crank gear  331  a larger angle, and rotating the driveshaft  333  faster. Therefore, less wave energy is used for uplifting the lifting load, and more wave energy is used for rotating the driveshaft  333  and generating electric energy. When the waves recede, the gravity drags the buoy  21  down because the lifting load is heavier than the counterweight  62 . 
     For example, suppose the total weight of lifting load, including the buoy  21 , the power input shafts  31 , the threaded rod adjustment devices  40 , and the flexible pivot assemblies  32 , is 500 kg, the counterweight is 400 kg, and the uplifting capacity of the waves is 1000 kg. Without the counterweight  62 , the waves have to spend 500 kg to uplift the lifting load, leaving 500 kg for driving the driveshaft  333  to generate electric energy. With the counterweight  62 , the waves need to spend just 100 kg (500 kg-400 kg) to uplift the lifting load, leaving 900 kg for driving the driveshaft  333  to generate electric energy. 
     Therefore, the counterbalancing and maintenance device  60  increases the wave energy used to drive the driveshaft  333  and the generator assembly  50  to generate electric energy. The counterbalancing and maintenance device  60  improves the energy conversion efficiency of the intelligent control wave energy power generating system  10 . 
     Adjustment, Maintenance, and Safety: The intelligent control system  70  monitors the state of the intelligent control wave energy power generating system  10  through the sensors and meters, including the anemoscope  73 , the speed sensor  74 , the position sensor  75 , and the wattmeter  76 . Based on the feedback of the sensors and meters (including e.g. angle δ), the unit control center  71  can raise or lower the threaded rod  311  (i.e. increase or decrease distance xy) through the threaded rod adjustment device  40  and activate or deactivate the generator  51 , to improve the energy conversion efficiency. The intelligent control system  70  can also uplift the buoy  21  and shut down the intelligent control wave energy power generating system  10  in severe wave and weather conditions. 
     Threaded Rod Adjustment: 
       FIG. 10  illustrates the rotary reciprocation of the crank gear  331 . As described above, the crank gear  331  rotates reciprocally in a region between the high position A and the low position B, which is the rotating region of the crank gear  331 . As shown in  FIG. 10 , when the waves rise from their troughs to their peaks, uplifting the buoy  21 , the crank gear  331  turns from the low position B at six thirty o&#39;clock, passing the middle position M at nine o&#39;clock, to the high position A at eleven thirty o&#39;clock. When the waves recede from their peaks to their troughs, dropping the buoy  21 , the crank gear  331  turns from eleven thirty o&#39;clock, passing nine o&#39;clock, to six thirty o&#39;clock. 
     The high position A and the low position B, and hence the rotating region of the crank gear  331  and angle θ, are determined by the wave height, the water level, and the distance between the flexible pivot device  32  and the buoy  21 . The crank gear  331  should be at nine o&#39;clock when the buoy  21  is at the water level (δ=0), which means its rotating region should be centered at nine o&#39;clock. For any given wave height, such rotating region maximizes wave energy output. Furthermore, such rotating region maximally excludes the two positions the crank gear  331  must avoid, i.e., the twelve o&#39;clock and the six o&#39;clock. The crank gear  331  would be stuck at these two positions and the waves would move the buoy  21  to crush the flexible pivot device  32 . For a specific wave height, the desirable rotating region is centered at nine o&#39;clock (δ=0). 
     However, due to fluctuations of the water level, the crank gear  331  may not rotate reciprocally in the desirable rotating region. The actual rotating region may be different from the desirable rotating region (δ≠0). The intelligent control system  70  monitors the rotating region of the crank gear  331  through the position sensor  75 . Based on the feedback of the position sensor  75 , the intelligent control system  70  determines the difference between the desirable rotating region and the actual rotating region (current δ value). If the intelligent control system  70  decides that the difference is big enough, it requests the threaded rod adjustment device  40  to raise or lower the threaded rod  311  to change the distance xy, or the distance between the flexible pivot device  32  and the buoy  21 , so that the actual rotating region will match the desirable rotating region (making δ=0 or close to 0). A longer distance between the flexible pivot device  32  and the buoy  21  turns the rotating region clockwise. A shorter distance between the flexible pivot device  32  and the buoy  21  turn the rotating region counterclockwise. 
     For example, if the desirable rotating region of the crank gear  331  is between ten o&#39;clock and eight o&#39;clock (θ=60° and δ=0°), and the actual rotating region is between nine o&#39;clock and seven o&#39;clock (θ=60° and δ=−30°), the threaded rod  311  is raised to increase the distance xy, or the distance between the flexible pivot device  32  and the buoy  21 , thus turning the rotating region of the crank gear  331  clockwise to be between ten o&#39;clock and eight o&#39;clock. With the threaded rod adjustment device  40 , the intelligent control system  70  can accommodate the fluctuations in the water level caused by tidal or seasonal changes, and keep the rotating region of the crank gear  331  close to the desirable rotating region (any θ&lt;180° value with δ=0°). 
     The operations of the threaded rod adjustment device  40  can be described using  FIG. 4 . The threaded rod adjustment device  40  rotates the threaded rod  311  to adjust the distance xy, or the distance between the flexible pivot device  32  and the buoy  21  which are not shown in  FIG. 4 . The motor  41  drives the gear shaft  43 . The gear shaft  43  rotates the drive gear  44 , driving the threaded driven gear  45 . Since the thrust bearing  46  is fastened to the adjustment device housing  42 , the vertical motion of the threaded driven gear  45  is restrained by the thrust bearing  46 . The threaded driven gear  45  does not move vertically as it rotates, but causes the threaded rod  311  to move up or down. The motor  41  can drive the gear shaft  43 , the drive gear  44 , and the threaded driven gear  45  to rotate either clockwise or counterclockwise, raising or lowering the threaded rod  311 , increasing or decreasing distance xy. 
     Generator Activation: The power ratings of the generators  51  are predetermined such that when the power ratings of the generators  51  are sorted in increasing order, the power rating of a later generator  51  exceeds the total power rating of the previous generators  51 . One embodiment of the generator assembly  50  is shown in  FIG. 3  with four generators  51 . We denote the four generators  51  as generators G 1 , G 2 , G 3 , and G 4 , in increasing order of their power ratings. In other words, the power rating of the generator G 4  is larger than the total power rating of the generators G 1 , G 2 , and G 3 ; the power rating of the generator G 3  is larger than the total power rating of the generators G 1  and G 2 ; and the power rating of the generator G 2  is larger than the power rating of the generator G 1 . 
     Based on historical wave data, wave energies are divided into fifteen levels. When wave energies exceed level fifteen, the wave conditions are deemed severe and the intelligent control system  70  will shut down all generators  51 . The four generators G 1 , G 2 , G 3 , and G 4 , are activated based on the level of wave energy. Table 1 shows the relationship between the generator activation and the wave energy level. 
     
       
         
               
             
               
               
             
               
               
             
           
               
                 TABLE 1 
               
             
             
               
                   
               
               
                 Relationship between wave energy level and generator activation 
               
             
          
           
               
                 Wave Energy up to Level 
                 Generator(s) Activated 
               
               
                   
               
             
          
           
               
                 1 
                 G1 
               
               
                 2 
                 G2 
               
               
                 3 
                 G2 + G1 
               
               
                 4 
                 G3 
               
               
                 5 
                 G3 + G1 
               
               
                 6 
                 G3 + G2 
               
               
                 7 
                 G3 + G2 + G1 
               
               
                 8 
                 G4 
               
               
                 9 
                 G4 + G1 
               
               
                 10 
                 G4 + G2 
               
               
                 11 
                 G4 + G2 + G1 
               
               
                 12 
                 G4 + G3 
               
               
                 13 
                 G4 + G3 + G1 
               
               
                 14 
                 G4 + G3 + G2 
               
               
                 15 
                 G4 + G3 + G2 + G1 
               
               
                   
               
             
          
         
       
     
     The combination of the generators  51  allows the generator assembly  50  work in a wider range of wave energy than a single generator. With a single generator, it will be damaged if the waves are too strong, or will not run if the waves are too weak. The combination of the generators  51  allows the intelligent control system  70  achieve appropriate power rating for the current wave energy level. Based on the feedback of the speed sensor  74  and the wattmeters  75 , the intelligent control system  70  decides how many generators  51  to activate. The intelligent control system  70  may activate one, two, three, or four generators  51 . 
     As shown in  FIG. 6 , the generator  51  is activated by engaging the clutch  521  of the clutch pulley  52  connected to the generator  51 . To deactivate the generator  51 , the clutch  521  of the clutch pulley  52  connected to the generator  51  is disengaged. 
     Maintenance and Safety: The intelligent control system  70  analyzes the feedback from the anemoscope  73 , the speed sensor  74 , and the wattmeters  76  to determine if the intelligent control wave energy power generating system  10  is working properly or is able to work properly under current wave and weather condition. If the intelligent control system  70  determines that the intelligent control wave energy power generating system  10  should be shut down due to its condition or the wave or weather condition, the intelligent control system  70  coordinates the counterbalancing and maintenance device  60  and the threaded rod adjustment device  40  to pull the buoy  21  up to a predetermined safe position. The intelligent control system  70  also stops the generators  51  to shut down the intelligent control wave energy power generating system  10 . 
     During the maintenance of the intelligent control wave energy power generating system  10 , the buoy  21  is uplifted to a predetermined position for cleaning, repairing, and so on. 
     As shown in  FIG. 11 , to uplift the buoy  21 , the intelligent control system  70  locks the counterweight  62  to the mounting platform  84  using the counterweight lock  63 . The intelligent control system  70  then coordinates the electric winch assembly  64  and the threaded rod adjustment device  40  to uplift the buoy  21  to a predetermined position for maintenance or safety. 
     Many other ramifications and variations are possible within the teachings of the various embodiments. For example, another embodiment of the gear transmission assembly  33  may include a crank gear and a ratchet gear connected by belts or chains. 
     In the foregoing specification, embodiments of the present invention have been described with reference to numerous specific details that may vary from implementation to implementation. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense. The sole and exclusive indicator of the scope of the invention, and what is intended by the applicant to be the scope of the invention, is the literal and equivalent scope of the set of claims that issue from this application, in the specific form in which such claims issue, including any subsequent correction.