Abstract:
This invention relates to a wave power generating device, comprising a lifting pillar installed on a floating platform, a sleeve covered outside said lifting pillar and two groups of ratchet wheel mechanisms installed on said sleeve; wherein the inner wheel of each of said ratchet wheel mechanisms rotates with the sleeve, the outer wheel of each of said ratchet wheel mechanisms drives a corresponding power generator to generate power; and the first outer wheel in the first group of ratchet wheel mechanism rotates with a first inner wheel along the first direction when the lifting pillar is rising, while the second outer wheel in the second group of ratchet wheel mechanism rotates with the second inner wheel along the second direction when the lifting pillar is falling. The wave power generating device of the invention has advantages of simple structure, low loss, and high power efficiency, and may transport much power energy for various uses.

Description:
CROSS REFERENCE TO THE RELATED PATENT APPLICATION 
   This application claims the priority of the Chinese patent application No. 200620135572.1 with filing date of Oct. 8, 2006. 
   FIELD OF THE INVENTION 
   This invention relates to a power generating device, more particularly, relates to a power generating device using up and down of ocean waves. 
   BACKGROUND OF THE INVENTION 
   Using up and down of ocean waves to generate power, is a newly researched energy, which is not only environment friendly but also always available for use. Presently, there have been many designs and plans using ocean waves to generate power, such as Chinese Patent Application with Publication No. CN1080692A, disclosing a wave power generating device, providing a stay rod attached to a concrete anchor block sinking to the seabed (epicontinental sea), or installing the stay rod on a stable plate kept in a certain depth under water (deep sea place), wherein the stay rod passes through a hole of a floating plate, thus the toothed rack (or frictional strip) on the stay rod is engaged (or contacted ) with the input gear (or friction gear) of the rotating transmission device on the floating plate where the rotating transmission device converts a bidirectional movement to an unidirectional movement; up-and-down movements of the ocean waves make the floating plate reciprocating along the stay rod, in such way, converting the reciprocating motion of the toothed rack into rotation motion of the gear, which is then converted into a unidirectional rotation motion utilized to drive a generator to generate power. This wave power generating device has complex structure, big loss, low efficiency, and not available for multiple uses. 
   BRIEF SUMMARY OF THE INVENTION 
   This invention provides a wave power generating device with simple structure and high power efficiency, to solve the insufficiency existing in the existing technology. 
   According to an aspect of the invention, a wave power generating device is provided, comprises a lifting pillar installed on a floating platform, a sleeve covered outside said lifting pillar, a first and second ratchet wheel mechanisms installed on said sleeve; wherein a external circumference of said lifting pillar is engaged with a inner circumference of said sleeve via screw threads, thereby said sleeve rotates along a first direction or a second direction with the rises and falls of the lifting pillar; the first or second ratchet wheel mechanisms comprises an inner wheel with multiple pawls and an outer wheel with corresponding multiple ratchets on its inner circumference, the inner wheel of the first or second ratchet wheel mechanisms is fixed on said sleeve and rotates with the sleeve, the outer wheel of the first or second ratchet wheel mechanisms drives a corresponding power generator to generate power; the pawls and the ratchets of the first ratchet wheel mechanisms are engaged with each other to make the outer wheel and inner wheel of the first ratchet wheel mechanism rotating together along the first direction when the lifting pillar is rising, the pawls and the ratchets of the second ratchet wheel mechanisms are engaged with each other to make the outer wheel and inner wheel of the second ratchet wheel mechanism rotating along the second direction when the lifting pillar is falling. 
   Advantageously, three traction gears are installed on the second outer wheel of said second ratchet wheel mechanism, engaged with a corresponding annular rack rail provided on the first outer wheel of said first ratchet wheel mechanism. 
   Advantageously, each of said traction gears is perpendicular to the second outer wheel, and positioned inside a corresponding through groove on the second outer wheel by a pin shaft, engaged with the annular rack rail on said first outer wheel. 
   Advantageously, the first outer wheel of said first ratchet wheel mechanism is supported by a rolling bearing with a #-shaped bracket attached on the sleeve, and the second outer wheel of said second ratchet wheel mechanism is supported on the first outer wheel by the traction gears. 
   Advantageously, the first outer wheel of said first ratchet wheel mechanism and the second outer wheel of the second ratchet wheel mechanism are respectively equipped with two or more centrifugal hammers along a radial direction on their external circumferences. 
   Advantageously, the screw threads on the external circumference of said lifting pillar is formed by an I-shaped steel rail wound regularly around the lifting pillar, and a corresponding spiral groove for receiving the steel rail is provided on the inner circumference of said sleeve. 
   Advantageously, said first or second inner wheel includes 8 pawls matching with the corresponding ratchets on the first or second outer wheel. 
   Advantageously, said first or second inner wheel includes 4 pawls matching with the corresponding ratchets on the first or second outer wheel. 
   Advantageously, each of said pawls includes a spring fixed on the first or second inner wheel and a lock core in the spring. 
   Advantageously, a wind power generator is attached on a bracket of said floating platform. 
   The wave power generating device in accordance with the present invention has advantages of simple structure, low loss, and high power efficiency, and the wave power generating device may transport much power energy for various uses. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Further explanation to the invention can be found in the following description in conjunction with the drawings, in which: 
       FIG. 1  is an overall structure schematic diagram of the wave power generating device in accordance with an embodiment of the invention. 
       FIG. 2  is a schematic diagram of the transmission portion of the wave power generating device in accordance with an embodiment of the invention. 
       FIG. 3  is a schematic diagram illustrating engagement between the lifting pillar and the sleeve of the wave power generating device in accordance with an embodiment of the invention. 
       FIG. 4  is a schematic diagram of the second group of ratchet wheel mechanism of the wave power generating device in accordance with one embodiment of the invention. 
       FIG. 5  is a schematic diagram of the first group of ratchet wheel mechanism of the wave power generating device in accordance with one embodiment of the invention. 
       FIG. 6  is a schematic diagram illustrating engagement between the pawls and the ratchets of the second group of ratchet wheel mechanism in accordance with another embodiment of the invention. 
       FIG. 7  is a schematic diagram illustrating engagement between the pawls and the ratchets of the first group of ratchet wheel mechanism in accordance with another embodiment of the invention. 
       FIG. 8  is a schematic diagram of the transmission portion of the wave power generating device in accordance with another embodiment of the invention. 
       FIG. 9  is a schematic diagram of the rolling bearing with a #-shaped bracket as shown in  FIG. 8 . 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   As shown in  FIG. 1 , the wave power generating device in accordance with the invention is installed on a floating platform  10  over the sea. The floating platform  10  is positioned inside the bracket  20  fixed on the seabed. A lifting pillar  90  is fixed on the floating platform  10 , which may rise and fall with the floating platform. The lifting pillar  90  is covered with a sleeve  80  on its outside, and engaged with each other via screw threads, thus during the rises and falls process of the lifting pillar  90 , the sleeve  80  is driven by the screw threads to rotate counterclockwise or clockwise. The sleeve  80  equips with two ratchet wheel mechanisms rotating oppositely relative to each other, that is, a first ratchet wheel mechanism  70  on the downside and a second ratchet wheel mechanism  60  on the upside. Each ratchet wheel mechanism  60  or  70  comprises an inner wheel with a plurality of pawls and an outer wheel with a plurality of corresponding ratchets on its inner circumference, the specific structure of which will be explained hereafter. As shown in Figures, the first outer wheel  71  of the first ratchet wheel mechanism  70  drives a first generator  40  to generate power through a belt  110 , and the second outer wheel  61  of the second ratchet wheel mechanism  60  drives a second generator  30  to generate power through a belt  110 . Besides, in order to increase the generating power, one or more wind power generator is further installed in the four comers of the bracket  20  for supplement. 
   Specific structure of the transmission portion of the wave generating power device in accordance with the invention is shown in  FIG. 2  and  FIG. 3 . As shown in  FIG. 3 , an I-shaped steel rail  91  is wound counterclockwise about the external circumference of the lifting pillar  90  in a regular interval to form the spiral threads. Correspondingly, the inner circumference of the said sleeve  80  is provided with a spiral groove  81  for receiving the steel rail. Thread engagement between the lifting pillar  90  and the sleeve  80  could be achieved by such structure. When the floating platform  10  rises under the action of ocean waves, the lifting pillar  90  rises, and in turn the sleeve  80  rotates counterclockwise (viewing from below) driven by the thread rotation; vice versa, when the floating platform falls under the action of ocean waves, the lifting pillar  90  falls, and in turn the sleeve  80  rotates clockwise. Obviously, the rotation direction of the sleeve  80  with respect to the rises and falls of the lifting pillar  90  may be changed by changing the rotation direction of the thread on the lifting pillar  90 . 
   As shown in  FIG. 2 , the sleeve  80  equips with two ratchet wheel mechanisms, i.e. the first ratchet wheel  70  below and the second ratchet wheel  60  above. As shown in combination with  FIG. 5 , the first ratchet wheel mechanism  70  comprises a first inner wheel and a first outer wheel. The first inner wheel includes a plurality of pawls  73 , each formed by a spring and a lock core positioned in the spring. As shown in  FIG. 5 , there are 8 pawls, but it is not a limit to the present invention, and 4 pawls shown in  FIG. 7  is also an alternative. The first inner wheel comprising a plurality of pawls is fixed to the sleeve  80  directly and rotates with the sleeve  80 . As shown in Figures, a plurality of ratchets  72  engaged with the pawls are formed in the inner circumference of the first outer wheel  71 . When the first inner wheel rotates counterclockwise with the sleeve  80 , each pawl  73  contacts against the end surface of the corresponding ratchet  72  and drives the first outer wheel  71  to rotate together, this state is called “Real Gear”; when the first inner wheel rotates clockwise with the sleeve  80 , each pawl  73  contracts back under the function of the spring, and the first outer wheel  71  continues rotating clockwise under the effect of gravity, this state is called “Empty Gear”. So, whatever the ocean waves rise or fall, the first outer wheel  71  of the first ratchet wheel mechanism  70  always rotates counterclockwise, driving the generator to generate power. Further, the first outer wheel  71  also comprises an annular rack rail  75  along the edge of its top surface. The annular rack rail is utilized to realize a mutual traction between the two ratchet wheel mechanisms, the specific description of which will be further explained hereafter. In a embodiment of the invention as shown in  FIG. 8 , the first outer wheel  71  of the first ratchet wheel mechanism  70  may be supported by a rolling bearing  130  with a #-shaped bracket  132 . Specifically as shown in  FIG. 9 , a inner ring  134  of the rolling bearing  130  is fixed on the sleeve  80 , and a outer ring  136  of the rolling bearing  130  together with the #-shaped bracket  132  are utilized to support the first outer wheel  71 , thus the first outer wheel may rotate freely. 
   The structure of the second ratchet wheel mechanism  60  is shown in  FIG. 2  and  FIG. 4 , comprising a second inner wheel and a second outer wheel. The structure of the second inner wheel is similar to the first inner wheel, also comprising a plurality of pawls, fixed on the sleeve  80  and rotating with the sleeve  80 . As shown in  FIG. 4 , 8 pawls are provided for the second inner wheel, but this is not a limit to the invention, 4 pawls as shown in  FIG. 6  is also an alternative. The structure of the second outer wheel  61  is similar to that of the first outer wheel  71 , wherein a plurality of ratchets  62  corresponding to the pawls  63  are formed on the inner circumference of the second outer wheel. When the second inner wheel rotates clockwise with the sleeve  80 , each pawl  63  contacts against the end surface of the corresponding ratchet  62  and drives the second outer wheel  61  to rotate together, this state is called “Real Gear”; when the second inner wheel rotates counterclockwise with the sleeve  80 , the pawl  63  contracts back, and the second outer wheel  61  continues rotating clockwise under the effect of gravity, this state is called “Empty Gear”. So, whatever the ocean waves rise and fall, the second outer wheel  61  of the second ratchet wheel mechanism  60  always rotates clockwise, driving the generator to generate power. 
   Additionally, as shown in  FIG. 2 , the second outer wheel  61  also equips with a traction gear  100 , preferably 3 traction gears evenly distributed along the circumference (other two traction gears are not shown in the figures), individually engaged with a corresponding annular rack rail  75  on the first outer wheel  71 . These three traction gears  100  are perpendicular to the end surface of the second outer wheel  61 , each are positioned in a corresponding through groove  64  distributed every 120 degree along the circumference of the second outer wheel  61  by a pin shaft, and can rotate about the pin shaft. The bottom portion of the traction gears  100  get through the second outer wheel  61  and then engage with the annular rack rail  75  provided along the external circumference of the first outer wheel  71 . In such a way, the second outer wheel  61  is supported above the first outer wheel  71  and also a mutual traction between the two outer wheels is realized. For example, When the first outer wheel  71  rotates counterclockwise, the second outer wheel  61  rotates clockwise through the mutual action between the traction gears  100  and the rack rail  75 ; in the same way, when the second outer wheel  61  rotates clockwise, the first outer wheel  71  rotates counterclockwise through the mutual action between the traction gears  100  and the rack rail  75 . In such a way, during the whole process of the floating platform  10  and the lifting pillar  90  rising and falling driven by the ocean waves, the first outer wheel  71  and the second outer wheel  61  are ensured to rotate continuously without any stop, driving the corresponding generators  40  and  30  to generate power continuously, thus the energy from the rises and falls of the ocean waves are substantially utilized. 
   Further, two or more centrifugal hammers  120  are respectively attached on the external circumferences of the first outer wheel  71  and the second outer wheel  61  along their radial direction. Because of the traction of the centrifugal hammers  120 , the centrifugal force is increased, and then the rotation force and rotation speed of the two outer wheels are increased, accordingly increasing the power of the two generators driven by the belt  110 . In order to prevent the second outer wheel  61  of the ratchet wheel mechanism flying away from the upside during the rotation process, a fixing ring (not shown in the figure) may be attached on the sleeve  80  above the second ratchet wheel mechanism  60 , to prevent the second outer wheel  61  flying away during the rotation process. The fixing ring may be implemented in various manners. 
   Further explanation to the transmission process of the wave generating power device in accordance with one embodiment of the invention is provided below. As shown in  FIG. 2 , when the sleeve  80  rotates counterclockwise driven by the rises of the lifting pillar  90  with the ocean waves, the first ratchet wheel mechanism  70  is on “Real Gear”, wherein the first outer wheel  71  rotates counterclockwise driven by the pawls, then driving the first generator  40  to generate power; simultaneously, the second ratchet wheel mechanism  60  is on “Empty Gear”, wherein the second inner wheel rotates counterclockwise with the sleeve  80 , while the second outer wheel  61  continues rotating clockwise under the action of the traction gears  100  and the centrifugal hammers  120 , then driving the second generator  30  to generate power. When the sleeve  80  rotates clockwise driven by the falls of the lifting pillar  90  with the ocean waves, the second ratchet wheel mechanism  60  is on “Real Gear”, wherein the second outer wheel  61  rotates clockwise driven by the pawls, then driving the second generator  30  to generate power; simultaneously, the first ratchet wheel mechanism  70  is on “Empty Gear”, wherein the first inner wheel rotates clockwise with the sleeve  80 , while the first outer wheel  71  continues rotating counterclockwise under the action of the traction gears  100  and the centrifugal hammers  120 , then driving the second generator  30  to generate power. Thus in the whole process of rises and downs of ocean waves, the first outer wheel  71  always rotates counterclockwise, driving the first generator  40  continuously generating power, and the second outer wheel  61  always rotates clockwise, driving the second generator  30  continuously generating power. 
   According to the surface area of the floating platform over the sea, several sets of the above-mentioned wave power generating device may be installed on the floating platform, therefore sufficient power energy is generated for various use. For example, the power energy generated by the wave power generating device can be used for thermal power plant, which is enough for power supply of a city.