Patent Publication Number: US-2015075304-A1

Title: Hand-operating starting device with clutch structure

Description:
(a) TECHNICAL FIELD OF THE INVENTION 
     The present invention generally relates to a starting device applicable to starting an engine of for example a remote control vehicle, a yacht, a lawnmower, and a power generator, and more particularly to a hollowed casing structure of a cable reel. 
     (b) DESCRIPTION OF THE PRIOR ART 
     A regular remote control vehicle generally comprises an engine that is started by an electrically operating starting device. An example is disclosed in Taiwan Patent No. 242278, which discloses an improved structure of an ancillary starting device of an engine of a remote control vehicle, wherein the structure is characterized by comprising a driving gear train and a driven gear train. The driving gear train comprises a housing and the housing has a circumference that is provided with a hollow axle sleeve set at an angle of around 45 degrees and in communication with a receiving section. The hollow axle sleeve receives an axle extending therethrough. The axle has a top end forming a coupling section. The axle has a bottom end to which a driving bevel gear is mounted in such a way that the driving bevel gear is located in the housing. The driven gear train comprises a cover that is set on the housing. The cover comprises a through hole that receives and retains therein a one-way bearing. The one-way bearing receives a spindle extending therethrough. The spindle has an end to which a driven bevel gear is mounted to mate the driving bevel gear. The spindle has an opposite end coupled to the engine of the remote control vehicle. As such, an electrically operating tool is insertable into the coupling section of the driving gear train for rotation so as to drive the spindle of the driven gear train to rotate to thereby start the engine coupled to the opposite end of the spindle. 
     Thus, the structure disclosed in the Taiwan patent can be operated electrically for staring the engine. However, the engine, after being started, is put into operation and the spindle that is coupled to the engine is forced to rotate with the operation of the engine. Since the driven bevel gear that is mounted to an end of the spindle is in engagement with the driving bevel gear, the driving gear train is also forced to move. As a result, the power output of the engine is impeded by the driving gear train so as to result in a loss of power. Thus, it is desired to provide a starting device that comprises a clutch structure and to have a starting structure thereof disengaging from a spindle of an engine after the engine has been started so as to avoid power loss of the engine. 
     If the engine is not designed to separate from the starting structure of an engine starting device after starting, then a common solution is to provide a one-way bearing in the starting device. However, the power output of the engine may still be impeded (generally in the form of speed reduction and loading), to some extents, by the starting structure of the engine starting device. Consequently, the idle speed of the engine must be raised and this certainly leads to additional consumption of fuel. 
     Further, to use a remote control vehicle that includes an electrically operating starting device outdoors, a user need to carry associated electrically operating tools and equipment. This increases carrying loading and also causes concern about when the electrically operating starting device runs out of electrical power without being timely noticed. Thus, it is desired to provide a hand-operating starting device. 
     Thus, the present invention aims to provide a starting device that assists starting of an engine and is applicable to a yacht engine, a lawnmower engine, or a power generator engine. 
     SUMMARY OF THE INVENTION 
     An object of the present invention is to provide a hand-operating starting device with clutch structure, which comprises an arrangement constituted by a positioning pin and helical channel to allow for both axial movement and rotation, whereby after a user has started an engine, the starting structure that drives the engine is separated from a main shaft of the engine so as to avoid loss of power of the engine. 
     Another object of the present invention is to provide a hand-operating starting device with clutch structure, which allows for starting of an engine through hand operation without assistance from electrically-operating equipment and consuming no additional electrical power. 
     A further object of the present invention is to provide a hand-operating starting device that is applicable to starting an engine of a remote control vehicle or an engine of a yacht or an engine of a lawnmower or an engine of a power generator with hand operation so that the operation of the engine is more economic in fuel consumption. 
     To achieve the objects, the present invention is mounted to one side of an engine and comprises a driving portion and a driven portion. The driving portion comprises a housing forming a receiving section. The receiving section receives therein a rotary member around which a pull cord is would. The pull cord has an end extending outside the housing. The pull cord has an opposite end fixed to the rotary member. The rotary member comprises an elastic member mounted to one end thereof to provide a restoration force for reverse rotation of the rotary member after the rotary member has been rotated. The rotary member is coupled to an axle. The axle has a surface from which a positioning pin projects. The driven portion comprises a cover, which is set to cover the receiving section of the housing. A sleeve that comprises a fixation pin and a helical channel formed thereon is received in the cover in such a way that the sleeve is movably fit over the axle and the positioning pin is received in and guided by the helical channel, whereby the sleeve is rotatable and is movable, during the rotation thereof, to a position where the fixation pin is in driving engagement with the engine. As such, assistance is provided for starting up an engine. After the engine has been started, the fixation pin is allowed to separate from a driving position for driving the engine so that the power output of the engine is not impeded by the sleeve and no loss of power will be caused. 
     The foregoing objectives and summary provide only a brief introduction to the present invention. To fully appreciate these and other objects of the present invention as well as the invention itself, all of which will become apparent to those skilled in the art, the following detailed description of the invention and the claims should be read in conjunction with the accompanying drawings. Throughout the specification and drawings identical reference numerals refer to identical or similar parts. 
     Many other advantages and features of the present invention will become manifest to those versed in the art upon making reference to the detailed description and the accompanying sheets of drawings in which a preferred structural embodiment incorporating the principles of the present invention is shown by way of illustrative example. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded view of the present invention. 
         FIG. 2  is a perspective view of the present invention. 
         FIG. 3  is a cross-sectional view of the present invention. 
         FIG. 4  is a schematic view, partially broken, illustrating a starting operation of the present invention. 
         FIG. 4A  is a cross-sectional view of  FIG. 4 . 
         FIG. 5  is another schematic view, partially broken, illustrating the starting operation of the present invention. 
         FIG. 5A  is a cross-sectional view of  FIG. 5 . 
         FIG. 6  is a schematic view illustrating an operation of the present invention after the engine has been started. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The following descriptions are exemplary embodiments only, and are not intended to limit the scope, applicability or configuration of the invention in any way. Rather, the following description provides a convenient illustration for implementing exemplary embodiments of the invention. Various changes to the described embodiments may be made in the function and arrangement of the elements described without departing from the scope of the invention as set forth in the appended claims. 
     Referring to  FIGS. 1-3 , the present invention is mounted to one side of an engine  3 . The engine  3  can be for example an engine of a remote control vehicle, an engine of a yacht, an engine of a lawnmower, or an engine of a power generator. A preferred embodiment of the present invention comprises a driving portion  1  and a driven portion  2 . 
     The driving portion  1  comprises a housing  11 . The housing  11  has an interior that defines a hollow receiving section  12 . The receiving section  12  receives therein a rotary member  13 . The rotary member  13  comprises a groove  131  formed therein for receiving a predetermined length of a pull cord  14  wound therein. The pull cord  14  has an end extending out of the housing  11  and coupled to a T-shaped handgrip  15 , whereby a user is allowed to grip the handgrip  15  with a hand for pulling the pull cord  14  to rotate the rotary member  13 . The pull cord  14  has an opposite end that is fixed to the rotary member  13 . Mounted to one end of the rotary member  13  is an elastic member  16  (see  FIG. 3 ) that, after the rotary member  13  has been rotated in a forward direction, provides a restoration force for reverse rotation of the rotary member  13 . The elastic member  16  can be for example a spring. The rotary member  13  comprises a polygonal bore  132  formed therein. In the instant embodiment, the polygonal bore  132  is a hexagonal hole having six interconnected sides. An axle  17  comprises a polygonal coupling section  171  that corresponds in shape to the polygonal bore  132  so as to allow the polygonal coupling section  171  to be fit into the polygonal bore  132  to have the rotary member  13  coupled to the axle  17  for driving the axle  17  to rotate. Further, the axle  17  has an end that extends beyond the rotary member  13  to be rotatably received in a recess  111  defined in an inside surface of the housing  11  (see  FIG. 3 ), serving as an axis supporting the rotation of the rotary member  13  and the axle  17 . Further, the axle  17  has a circumferential surface from which a positioning pin  18  projects. 
     The driven portion  2  comprises a cover  21 . The cover  21  is fixed by a plurality of threaded fasteners (not shown) extending therethrough so as to cover and close the receiving section  12  of the housing  11 . The cover  21  is further fixed by a plurality of additional threaded fasteners  26  extending therethrough to the side of the engine  3  so as to allow the present invention to be mounted to the side of the engine  3 . The cover  21  comprises a lining  22  for wear/abrasion resistance and a sleeve  23  that is received in the lining  22  and comprises a fixation pin  231  and a helical channel  232  formed thereon. The helical channel  232  is formed, circumferentially, in a circumferential surface of the sleeve  23  and extends by a predetermined length. The sleeve  23  is movably fit over the axle  17  in such a way that the positioning pin  18  is movably received in and guided by the helical channel  232  to move along the helical channel  232 , serving as a structure for achieving both rotation and axial movement, for driving an axial movement of the sleeve  23  along the axle  17  and enabling the sleeve  23  to rotate with the axle  17 . Further, due to the positioning pin  18  being guided, in a helical manner, by the helical channel  232 , the sleeve  23  may cause the fixation pin  231  to move to a location to drive the engine  3 . 
     The circumferential surface of the sleeve  23  is provided with a plurality of positioning grooves  233  circumferentially arranged thereon. The cover  21  is provided with a spring  24  that is arranged in a radial passage of the cover so that the spring  24  biases a positioning ball  25  to set the positioning ball  25  in an elastically biased condition to selectively fit into and engage one of the positioning grooves  233 . As such, the sleeve  23  is allowed to move forward and backward in the axial direction along the axle  17 , while positionability can be achieved during a backward axial movement of the sleeve  23  after the engine has been started in order to prevent the sleeve  23  from being undesirably moved forward caused by the vibration of the operation of the engine. 
     Referring to  FIGS. 4 and 4A , the engine  3  to which the present invention is applied generally has a structure that comprises a piston  31  having a crank  32  set at a bottom portion thereof. The piston  31  is connected, via an end of the crank  32 , to and drives an eccentric shaft  34  of a main shaft  33 . To start up the engine  3 , a user uses the handgrip  15  to pull the pull cord  14  to cause the rotary member  13 , together with the axle  17 , to rotate. The axle  17  drives the positioning pin  18  to rotate. Since the positioning pin  18  is received, in a manner of being guided thereby, in the helical channel  232  of the sleeve  23 , the positioning pin  18  is moved along and rotated about the helical channel  232 . During the movement of the positioning pin  18 , the positioning pin  18  is rotated while being kept at a fixed axial position, due to the guidance in a helical manner realized by the helical channel  232 , the sleeve  23  is caused to make an axial movement. With the positioning pin  18  received the helical channel  232 , a driving force is applied thereby to a side wall of the helical channel  232  to drive the sleeve  23  to move along the axle  17  in such a manner that the sleeve  23  moves towards the engine  3 , whereby the sleeve  23  is allowed to reach such a position where the fixation pin  231  engages and drives the eccentric shaft  34  of the engine  3 . 
     Referring to  FIGS. 5 and 5A , what is shown in the drawings is that the handgrip  15  has been pulled outward to cause the pull cord  14  to drive the axle  17  to rotate. When the positioning pin  18  is rotated at a fixed axial position so as to move downward through a relative movement with respect to and along the helical channel  232  to reach and be retained at a bottom closed end of the helical channel  232  (which corresponds to a bottom dead center), the sleeve  23  stops axially moving and the sleeve  23  is kept rotation at the fixed position of the bottom dead center. As such, the length that the sleeve  23  extends in the forward direction can be limited to ensure the fixation pin  231  is located at the position engaging and driving the engine  3  and to prevent excessive extension of the sleeve  23 . 
     When the extension length of the sleeve  23  reaches the fixed length, the positioning pin  18  applies a driving force to the lower closed end of the helical channel  232  to drive the sleeve  23  to synchronously rotate with the axle  17 , whereby the fixation pin  231  may drive the eccentric shaft  34  of the engine  3  to cause the main shaft  33  of the engine  3  to rotate and thus starting up the engine  3  (see  FIG. 5A ). 
     Referring to  FIGS. 4 and 6 , after the engine  3  has been started and the user does not further pull the pull cord  14 , the rotary member  13  is acted upon by the spring restoration force of the elastic member  16  so that the rotary member  13  and the axle  17  are rotated synchronously in the backward direction and the positioning pin  18  moves upward from the lower closed end of the helical channel  232  (namely the bottom dead center) to an upper closed end of the helical channel  232  (which corresponds to a top dead end). With the above described spatial arrangement of the positioning pin  18  and the helical channel  232  that allows for axial movement and rotation to be performed at the same time, in the same way, the positioning pin  18  drives the sleeve  23  to move along the axle  17  in the backward direction (namely, in the direction away from the engine  3 ), making the fixation pin  231  separating from the driving position where it drives the engine  3  to start, thereby releasing the driving condition, allowing the output power of the engine  3  not to be impeded by the starting structure of the present invention and not to cause any undesired loss of power. 
     Practical tests of the present invention show that the power output from the engine can be increased by 15% horsepower in comparison with to an engine that does not include the clutching operation. Further, due to the engine operation does not need to carry the loading of rotation of the starting device, the consumption of fuel of the engine can be reduced. 
     In summary, the present invention provides a hand-operating starting device with a clutch structure, which allows for ready engagement and disengagement between the starting structure and an engine and allows a user to start the engine by hand-pulling a pull cord based starting structure and requiring no electrical device and thus no additional electrical power to achieve starting of engine. Compared to the conventional engine starting devices, the present invention, as a whole, is novel. 
     It will be understood that each of the elements described above, or two or more together may also find a useful application in other types of methods differing from the type described above. 
     While certain novel features of this invention have been shown and described and are pointed out in the annexed claim, it is not intended to be limited to the details above, since it will be understood that various omissions, modifications, substitutions and changes in the forms and details of the device illustrated and in its operation can be made by those skilled in the art without departing in any way from the spirit of the present invention.