Patent Publication Number: US-2015060224-A1

Title: Driving device for a hub

Description:
FIELD OF THE INVENTION 
     The present invention relates to a driving device, and more particularly, to a single-part driving device for a hub and the driving device has better concentricity which is easily installed and dis-assembled. 
     BACKGROUND OF THE INVENTION 
     The conventional bicycle hub is located between the rear wheel and the flywheel, the axle extends through the hub so as to drive the rear wheel. A ratchet device is installed between the hub and the flywheel. By treading the pedals to drive the chain and the flywheel, the rear wheel is rotated to move the bicycle forward. 
     The conventional ratchet device and generally comprises a socket at one end of the hub and multiple pawls and ratchet teeth are engaged with each other and located between the socket and the hub. A resilient device is located between the pawls and ratchet teeth. The ratchet teeth each have two inclined faces on two sides thereof so that when the pawls are matched with one side of the ratchet teeth, the socket and the hub are co-rotated. When the pawls are matched with the other one side of the ratchet teeth, the resilient device is activated to disengage the socket from the hub. 
     The driving ways of the ratchet wheels of the conventional driving device generally are cataloged into the axial type and the radial type. The axial type means that the ratchet wheel has teeth extending along the axial direction of the hub so as to be cooperated with the axial ratchet teeth to transmit the force. The radial type means that the ratchet wheel has teeth extending along the radial direction of the hub so as to be cooperated with the radial ratchet teeth to transmit the force. 
     Taiwan Utility Model Application No. 100218595 discloses an axial type driving device and comprises an axle extending through a casing which has a connection end formed on an outside along the axial direction. The connection end has a fixing slot and a reception slot which is located on outside of the connection end. A chain-wheel base is rotatably connected to the axial and located at one end of the casing. The chain-wheel base has a connection portion and an installation portion, wherein the connection portion is located corresponding to the fixing slot and the installation portion is located on outside of the chain-wheel base. A clutch device is located between the casing and the chain-wheel base and has a positioning member located in the fixing slot, a clutch member axially located on one side of the positioning member, a driving member axially located on one side of the clutch member and fixed to the connection portion, and a resilient member located between the clutch member and the positioning member. The positioning member has multiple first engaging portions which are engaged with the second engaging portions on the clutch member. The clutch member further has a driven portion which is located in opposite to the second engaging portions. The driving member has multiple driving portions located corresponding to the driven member. The chain-wheel base drives the driving member to move toward one direction and the driving portions drive the driven portions to drive the clutch member from a remote position to be engaged with the positioning member so as to co-rotate the casing. The chain-wheel base is rotated relative to the casing, the resilient member is able to remove the clutch member from positioning member to allow the chain-wheel base to rotate individually. 
     Taiwan Utility Model Application No. 101203929 discloses a radial type driving device and comprises a one-direction clutch device in the hub which has a tubular casing, a spring, a first protrusion and a second protrusion. The casing has multiple recesses which are located alternatively in outside of the casing so as to accommodate the pawls of the one-direction clutch device. The spring biases the pawl to an upright position. The first and second protrusions are located at ends of the spring. 
     The clutch device of the first example has the positioning member, the clutch member, the driving member on the chain-wheel base and the resilient member located between the clutch member and the positioning member. The positioning member and the clutch member are engaged with each other the engagement between the first and second engaging portions. The chain-wheel base drives the driving member to move toward one direction and the driving portions drive the driven portions to drive the clutch member from a remote position to be engaged with the positioning member so as to co-rotate the casing. The chain-wheel base is rotated relative to the casing, the resilient member is able to remove the clutch member from positioning member to allow the chain-wheel base to rotate individually. The tubular casing of the second example has recesses for accommodating the pawls of the clutch device. The first and second protrusions are located at ends of the spring which biases the pawl to the upright position. 
     However, the parts of the driving device of the axial type are connected between the socket and the hub in the axial direction, there are too many parts involved so that these parts may shift in the axial direction. This can affect the engagement between the teeth and unbalance force is applied to the teeth which tend to be broken within a short period of time. Larger friction and noise are expected. The pawls of the radial type driving device are connected to the socket and biased upright when the socket is rotated, the pawls press the inside of the recesses. The gap between the pawls and the socket becomes larger along with the period of time of use, and this also affects the engagement of the pawls and the cooperated parts. 
     The present invention intends to provide a driving device for a hub and the driving device improves the shortcomings of the conventional ones. 
     SUMMARY OF THE INVENTION 
     The present invention relates to a hub assembly and comprises a hub having an axle extending axially therethrough and a space is defined in the first end of the hub. A connection ring is located in the space and has multiple first teeth extending axially from the inner periphery thereof A hollow socket has an open end in the first end thereof and a second end of the socket is connected with the flywheel of the bicycle. The open end has multiple second teeth extending axially from the inner periphery thereof The open end is inserted into the space and the axle extends through the socket. A driving unit is an integral unit and has a sleeve, a first ratchet ring, a second ratchet ring, two roller members and two resilient members. The first ratchet ring has third teeth extending axially from outside thereof. The second ratchet ring has fourth teeth extending axially from outside thereof. Multiple first ratchet teeth extend from one end face of the first ratchet ring and multiple second ratchet teeth extend from one end face of the second ratchet ring. The first and second ratchet rings are mounted to the sleeve, and the first and second ratchet teeth are engaged with each other. The two roller members are respectively located in the first and second ratchet rings. The two resilient members are two ring-shaped members and mounted to two ends of the sleeve respectively and are located outside of the first and second ratchet rings respectively. The driving unit is located in the space and the axle extends through the driving unit. The third teeth of the first ratchet ring are engaged with the first teeth of the connection ring. The fourth teeth of the first ratchet ring are engaged with the second teeth of the socket. The driving unit is connected between the connection ring and the socket. 
     The primary object of the present invention is to provide a driving unit of a hub assembly wherein the driving unit is an integral single part which is composed of a sleeve, a first ratchet ring, a second ratchet ring, two roller members and two resilient members. The driving unit is mounted to the axle. When the first and second ratchet rings rotate, the roller members provide the two ratchet rings to operate smoothly. The driving unit has higher concentricity so as to allow the two ratchet rings to share the force evenly to prevent them from being broken. The noise during operation is reduced. The driving unit can be easily replaced and assembled. Each of the roller members is a ring-shaped ball bearing or a self-lubrication bearing, and each of the resilient members is a resilient plate, a spring or a member made by PU. 
     The present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, a preferred embodiment in accordance with the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view to show the hub with the driving unit of the present invention; 
         FIG. 2  is an exploded view to show the hub with the driving unit of the present invention; 
         FIG. 3  is an exploded view to show the driving unit of the present invention; 
         FIG. 4  is a cross sectional view of the driving unit of the present invention; 
         FIG. 5  is an enlarged cross sectional view of a portion of the driving unit of the present invention; 
         FIG. 6  is a cross sectional view of the driving unit of the present invention when in operation; 
         FIG. 7  is an enlarged cross sectional view of a portion of the present invention in  FIG. 6 ; 
         FIG. 8  is an exploded view to show another embodiment of the driving unit of the present invention, and 
         FIG. 9  is a cross sectional view of the driving unit of the present invention in  FIG. 8 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to  FIGS. 1 to 5 , the hub assembly of the present invention comprises a hub  10 , a socket  20  and a driving unit  30 . 
     The hub  10  has an axle  11  extending axially therethrough and a space  12  is defined in the first end of the hub  10 . A connection ring  13  is located in the space  12  and has multiple first teeth  131  extending axially from the inner periphery thereof. The connection ring  13  has outer threads which are threadedly connected to the inner threads in the space  12 . 
     The socket  20  is a hollow socket and has an open end  21  in the first end thereof and the second end of the socket  20  is connected with a flywheel. The open end  21  has multiple second teeth  22  extending axially from the inner periphery thereof. The open end  21  is inserted into the space  12  and the axle  11  extends through the socket  20 . A stop ring  23  is located between the open end  21  of the socket  20  and the space  12  to prevent dust, water or other objects from entering the space. 
     The driving unit  30  is an integral unit and comprises a sleeve  31 , a first ratchet ring  32 , a second ratchet ring  33 , two roller members  34  and two resilient members  35 . The sleeve  31  is a tubular member and each of the two ends of the sleeve  31  has a radial stop portion  311  which is a protrusion or a recessed area. In this embodiment, the stop portion  311  is a flange. The first ratchet ring  32  has third teeth  321  extending axially from outside thereof, and the second ratchet ring  33  has fourth teeth  321  extending axially from outside thereof. Multiple first ratchet teeth  323  extend from one end face of the first ratchet ring  32 , and multiple second ratchet teeth  333  extend from one end face of the second ratchet ring  33 . The first and second ratchet rings  32 ,  33  are mounted to the sleeve  31 . The first and second ratchet teeth  323 ,  333  are engaged with each other. The first ratchet ring  32  has a first groove  322  defined in the inner periphery thereof and the second ratchet ring  33  has a second groove  332  defined in the inner periphery thereof. The roller members  34  are respectively engaged with the first and second grooves  322 ,  332 . The two resilient members  35  are two ring-shaped members and mounted to two ends of the sleeve  31  respectively and located outside of the first and second ratchet rings  32 ,  33  respectively. 
     Each of the resilient members  35  has first supports  351  extending from the inner periphery thereof, and each of the first supports  351  has a plate-shaped first protrusion  352  and a first end piece  353  which extends outward and axially from the distal end of the first protrusion  352 . Each of the resilient members  35  further has second supports  354  extending from the outer periphery thereof. Each of the second supports  354  has a plate-shaped second protrusion  355  and a second end piece  356  which extends outward and axially from the distal end of the second protrusion  355 . The two resilient members  35  are respectively mounted to the two ends of the sleeve  31  and located on outside of the first and second ratchet rings  32 ,  33  respectively. The first end pieces  353  contact the two stop portions  311  of the sleeve  31  respectively. The second end pieces  356  of the second supports  354  contact the other end faces of the two first and second ratchet rings  32 ,  33  respectively. Therefore, the first and second ratchet rings  32 ,  33  are resiliently positioned on the sleeve  31 . 
     The driving unit  30  is located in the space  12  and the axle  11  extends through the driving unit  30 . The third teeth  321  of the first ratchet ring  32  are engaged with the first teeth  131  of the connection ring  13 . The fourth teeth  331  of the first ratchet ring  32  are engaged with the second teeth  22  of the socket  20 . The driving unit  30  is connected between the connection ring  13  and the socket  20 . The roller members  34  provide support for the axial movement and rotational action. 
     Each of the roller members  34  is a ring-shaped ball bearing, a cupper ring or a self-lubrication bearing. Each of the resilient members  35  is a resilient plate, a spring or a member made by PU. 
     The driving unit  30  of the present invention is an integral unit and comprises a sleeve  31 , a first ratchet ring  32 , a second ratchet ring  33 , two roller members  34  and two resilient members  35 . When the hub  10 , the socket  20  and the driving unit  30  rotate, the roller members  34  provide support for the axial movement and rotational action. The concentricity is increased and the force is shared evenly by the two ratchet rings  32 ,  33  to prevent the two ratchet rings  32 ,  33  from being broken, and the noise is also reduced. The driving unit  30  is an integral single part which has higher precision and easily installed and disassembled. 
     When assembling, the two roller members  34  are respectively engaged with the first and second grooves  322 ,  332  of the first and second ratchet rings  32 ,  33 . The first and second ratchet rings  32 ,  33  are then mounted to the sleeve  31  to engage the first ratchet teeth  323  with the second ratchet teeth  333 . The two resilient members  35  are mounted to the two ends of the sleeve  31 . The first end pieces  353  contact the two stop portions  311  of the sleeve  31  respectively. The second end pieces  356  of the second supports  354  contact the other end faces of the two first and second ratchet rings  32 ,  33  respectively. The driving unit  30  is connected in the space  12  and the axle  11  extends through the driving unit  30 , so that the third teeth  321  are engaged with the first teeth  131 . The socket  20  is installed in the space  12  to engage the fourth teeth  331  with the second teeth  22 . 
     As shown in  FIGS. 6 and 7 , when in use, when the flywheel drives the socket  20  to rotate in one direction, the socket  20  drives the second ratchet teeth  333  to engage with the first ratchet teeth  323  to drive the hub  10 . When the flywheel drives the socket  20  to rotate in the opposite direction, the resilient members  35  separate the second ratchet teeth  333  from the first ratchet teeth  323 , so that the socket  20  rotates independently. 
     As shown in  FIGS. 8 and 9 , which show another embodiment of the present invention, wherein each of the resilient members  36  is a spirally coil spring and has a first supports  361  and a second support  362  on two ends thereof. The two resilient members  36  are respectively mounted to the two ends of the sleeve  31  and located on outside of the first and second ratchet rings  32 ,  33  respectively. The first supports  361  contact the two stop portions  311  of the sleeve  31  respectively, and the second supports  362  contact the other end faces of the two first and second ratchet rings  32 ,  33  respectively. 
     The driving unit  30  of the present invention is an integral unit and comprises a sleeve  31 , a first ratchet ring  32 , a second ratchet ring  33 , two roller members  34  and two resilient members  35 . When the hub  10 , the socket  20  and the driving unit  30  rotate, the roller members  34  provide support for the axial movement and rotational action. The concentricity is increased and the force is shared evenly by the two ratchet rings  32 ,  33  to prevent the two ratchet rings  32 ,  33  from being broken, and the noise is also reduced. The driving unit  30  is an integral single part which has higher precision and easily assembled and disassembled. 
     Each of the roller members  34  is a ring-shaped ball bearing, a cupper ring or a self-lubrication bearing. Each of the resilient members  35  is a resilient plate, a spring or a member made by PU. 
     While we have shown and described the embodiment in accordance with the present invention, it should be clear to those skilled in the art that further embodiments may be made without departing from the scope of the present invention.