Abstract:
A treadmill roller structure comprises a motor, a gear set and a case. The motor is an out-runner motor. The power output section of the motor rotates about stationary spindle. The rotary power output section is engaged to the gear set, while the gear set is in turn engaged to the case, thus allowing the case to rotate relatively to the spindle of the motor as well. The roller structure does not require a driving belt to transfer power from the motor to the roller, thus reduces the power loss due to frictional force during power transfer through belt driving, which enhances the performance of the motor and offers a space-saving feature. In addition, the instant disclosure also provides a treadmill.

Description:
RELATED APPLICATIONS 
     This application is a Divisional patent application of co-pending application Ser. No. 12/818,390, filed on 18 Jun. 2010, now pending. The entire disclosure of the prior application, Ser. No. 12/818,390, from which an oath or declaration is supplied, is considered a part of the disclosure of the accompanying Divisional application and is hereby incorporated by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The instant disclosure relates to a treadmill roller structure; in particular, the instant disclosure relates to a roller structure in a treadmill device. 
     2. Description of Related Art 
     In the modern world, dense metropolitan population and crowded living environment make it difficult for the city residents to find appropriate locations for sport activities and fitness exercises. To address such an issue, indoor sport equipments, such as treadmills, exercise bikes or skiing machines are developed. These equipments can be installed indoor, thus breaking the spatial constrains and temporal limitations. 
     In a conventional treadmill, a drive belt is employed to drive the rollers. In a conventional setup, a front roller and a rear roller are respectively installed at the front side and the rear side of the base, and a treadmill belt is then set between the front roller and the rear roller, thereby enabling the treadmill belt to cyclically rotate for a user&#39;s jogging. Power is transferred through a belt placed between the front roller and a motor, and the power output axle of the motor is connected to one end of the belt, while the front roller connected to the other end thereof. Therefore, as the motor operates, the belt brings the front roller to rotate, and the front roller in turn links the treadmill belt, so the treadmill belt can cyclically rotate between the front roller and the rear roller. 
     However, separate installations of the motor and the front roller in a prior art treadmill may cause following drawbacks. It is required to reserve space in advance for placement of the motor n the treadmill base, so the area taken by the treadmill can be exceedingly large which may not be suitable for domestic applications. Besides, the configuration of separately installed motor needs to use an additional belt to bring the front roller to rotate. Frictions exist respectively between the belt and motor output axle as well as between the belt and the front roller, and such frictions neutralize certain parts of motor output power, undesirably leading to partial losses during transfer of motor output power. Furthermore, idle rotations tend to occur in case that the speed of belt transfer becomes too fast while the contact friction between the belt and the front roller is insufficient, so the power output from the motor may not be efficiently transferred the front roller, thus also resulting in unwanted partial losses in motor output power during power transfer. 
     Accordingly, in view of the amendable drawbacks illustrated as above, the inventors of the instant disclosure, based on long-term studies along with profound technical and theoretical researches, provide a design disclosed herein which effectively improves the defects set forth in the aforementioned texts. 
     SUMMARY OF THE INVENTION 
     The objective of the instant disclosure is to provide a treadmill roller structure and a treadmill which configures the motor and the gear set inside or outside of the roller, such that the roller can actively rotate, facilitating enhancement in performance of the motor and the feature of space saving. In addition, it is not required to use a belt to bring the roller to rotate, so the friction losses during power transfer can be desirably reduced, thereby increasing efficiency of the motor as well. 
     To achieve the objective mentioned as above, the instant disclosure provides a treadmill roller structure, comprising: a motor, which is an inner-piece out-runner motor and consists of a spindle and a power output section, wherein the power output section rotates relatively to the spindle; a gear set, which is fixedly installed to the spindle, wherein the power output section engages with the gear set; and a case, wherein the gear set engages with the case, and the case rotates relatively to the spindle. 
     The instant disclosure also provides a treadmill which comprises a base, wherein a front roller and a rear roller are respectively installed at the front end of the base and the rear end of the base, and a treadmill belt is set between the front roller and the rear roller, characterized in that, one of the front roller and the rear roller comprises: a motor, which is an inner-piece out-runner motor and consists of a spindle and a power output section, wherein the power output section rotates relatively to the spindle; a gear set, which is fixedly installed to the spindle, wherein the power output section engages with the gear set; and a case, wherein the gear set engages with the case, and the case rotates relatively to the spindle. 
     The instant disclosure enables the following beneficial effects: 
     1. since the motor and the gear set are installed inside or outside of the case, the power generated by the motor can bring the case to rotate directly through the engagement between the gear set and the inner gear ring. The case can thus actively rotate without additional use of belt, hence advantageously lessening motor output power losses which may occur during transfer. Besides, simplified roller structure also facilitates reduction of manufacture cost; 
     2. as the motor operates, the outputted motor power enables the power output section to rotate, thereby linking the solar gear so in turn the planetary gear, further together generating rotations of the inner gear ring and the case. In this way, by means of the tooth number ratio between the solar gear and the planetary gear, the output power from the motor can be amplified in multiples, efficiently transferred to the case so as to increase the performance of the motor; 
     3. the motor can be as demand installed inside or outside of the case, so it needs not to reserve space in advance for placement of the motor, thereby effectively scaling down the area required for installation of the treadmill, improving convenience in use and facilitating easy transportation. 
     In order to further appreciate the features and technical contents of the instant disclosure, references are hereunder made to the detailed descriptions of the instant disclosure and appended drawings therefore; whereas the appended drawings are simply exemplary and illustrative, rather than for the purpose of limitations to the instant disclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an assembly graph of the treadmill roller structure and the treadmill according to the instant disclosure. 
         FIG. 2  is a disassembly graph for a first preferred embodiment of the treadmill roller structure according to the instant disclosure. 
         FIG. 3  is a three dimensional view for the first preferred embodiment of the treadmill roller structure according to the instant disclosure. 
         FIG. 4  is a three dimensional view for a second preferred embodiment of the treadmill roller structure according to the instant disclosure. 
         FIG. 5  is a disassembly graph for a third preferred embodiment of the treadmill roller structure according to the instant disclosure. 
         FIG. 6  is a three dimensional view for the third preferred embodiment of the treadmill roller structure according to the instant disclosure. 
         FIG. 7  is a three dimensional view for a fourth preferred embodiment of the treadmill roller structure according to the instant disclosure. 
         FIG. 8  is a cross-section view for a fifth preferred embodiment of the treadmill roller structure according to the instant disclosure. 
         FIG. 9  is a cross-section view for a sixth preferred embodiment of the treadmill roller structure according to the instant disclosure. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring initially to  FIGS. 1 ,  2  and  3 . The instant disclosure provides a treadmill roller structure. The roller structure is installed at the front and the rear end of the base  101  of a treadmill  10  to the treadmill belt  102  around the front and the rear roller  103 . The roller  103  comprises a motor  1 , a gear set  2 , a case  3  and a plurality of motion limiting assemblies  4 . 
     The motor  1  is an out-runner motor having a motor axle bore  11 , an accommodation chamber  12 , a spindle  13  and a power output section  14 . The motor axle bore  11  is located in the accommodation chamber  12  of the motor  1 . The accommodation chamber  12  is able to accommodate the motion limiting assemblies  4 . The spindle  13  passes through the motor axle bore  11  of the motor  1 , the gear set  2 , the case  3 , and the motion limiting assemblies  4 . The spindle  13  is a fixed supporting structure that does not rotate; rather, the motor  1  is installed through the spindle  13  in a fashion that the rotating belt of the motor rotates about the stationary spindle  13 . The power output section  14  is rigidly installed to the rotating belt of the motor  1  and is thus rotatable about the stationary spindle  13  to drive the gear set  2  when power is supplied to the motor. Moreover, the spindle  13  is installed in a cross-over fashion to the base  101  of the treadmill  10  as a supportive axle for the roller  103 . 
     Gear set  2  comprises of a fixing seat  21 , a plurality of planetary gears  22 , and a solar gear  23 . The fixing seat  21  has an axle bore  211  at the center for fitting through the spindle  13 . The fixing seat is installed on one side of the motor  1 . The planetary gears  22  are rotatably mounted to the fixing seat  21  on axle bores  221  such that the three planetary gears  22  are allowed to rotate around individually with respect to bearing  221 . The planetary gears  22  are located between the motor  1  and the fixing seat  21 . The solar gear  23  is rigidly installed on the power output section  14 , enabling synchronous rotations. In addition, the solar gear  23  engages with each of the planetary gears  22  to bring each planetary gear  22  into self-rotational motion around the bearing  221 . 
     The gear set  2  is engaged to a gear ring  33  of the case  3  to enable rotations of the case  3 . Particularly, the case  3  is a hollow cylindrical case. One end of the case  3  is installed to a locking section  31 . The locking section  31  includes a plurality of locking holes  311  enabling rigid fixation between the cover  34  and the locking section  31  by the locking element  312 . Inside the case  3  there is an accommodation space  32  and an inner gear ring  33 . The inner gear ring  33  is rigidly installed to the inner wall of the case  3 . In a first preferred embodiment, the motor  1  and the gear set  2  are placed in the accommodation space  32  inside of the case  3  with each of the planetary gears  22  simultaneously engaging with the solar gear  23  and the inner gear ring  33 , such that the case  3  can be linked to rotate by means of the inner gear ring  33  as the planetary gears  22  rotate. Thus, when the power output section  14  rotates about the spindle  13 , the gear set  2  will be driven to drive the inner gear ring  33 , and thus causing rotation of the case  3 . However, although the motor  1  and the gear set  2  according to the instant disclosure are installed to one end inside of the case  3 , it is by no means limited thereto; rather, it is possible to adjust the positions inside of the case  3  wherein the motor  1  and the gear set  2  are actually placed based on application requirements for achieving the same effect as the instant disclosure. Furthermore, in a second embodiment (as shown in  FIG. 4 ), two motors are used to drive the roller structure. One motor is installed at each end of the accommodation space  32  inside of the case  3  for enhancing the output power to the roller. Also, the roller  103  is individually installed to the front end of the base  101  and the rear end of the base  101  (as shown in  FIG. 1 ), with one of the two rollers  103  being installed with the motor  1  and the gear set  2  so that the treadmill belt  102  can be brought to rolling motion around the front and rear rollers  103 . In other words, the rear roller  103  may not require a motor  1  and a gear set  2 ; instead, the motor from the front roller along may provide all the driving power to the treadmill belt. Moreover, the instant disclosure employs the gear set  2  as a gear-reduction mechanism to increase torque output. For instance, the gear set  2  transfers the power from the power output section  14  having a smaller radius to the inner gear ring  33  of a greater radius, thus enabling power conversions from the power output section  14  having high rotation speed and low torque to the inner gear ring  33  of low rotation speed and high torque, thus increasing the torque output to the case  3 . However, it is noted that the gear set  2  may be also replaced with other general real-reduction mechanisms for achieving the same results. 
     The motion limiting assemblies  4  are installed onto the spindle  13 . Each motion limiting assembly  4  comprises a bearing  41  and a fastener  42 . The spindle  13  passes through the motion limiting axle bore  411  of the bearing  41 , and the fastener  42  is buckled onto the spindle  13 . Thus, the fastener  42  props up the bearing  41  to refrain the bearing  41  from sliding. 
     The spindle  13  and the accommodation space  32  of the instant disclosure may be of different designs, as referring to  FIGS. 5 and 6 . In a third preferred embodiment, the spindle  13 A is installed with a motor axle  131 A, a linking element  132 A and a roller axle  133 A, and the motor axle  131 A acts as the rotation center axle of the motor  1 , the roller axle  133 A as the rotation center axle of the case  3 , while the motor axle  131 A is set to the outside of the roller axle  133 A and the linking element  132 A clips in connection between the motor axle  131 A and the roller axle  133 A (as shown in  FIG. 6 ). Additionally, the case  3  is externally installed in fixation with an accommodation section  32 A, with the accommodation section  32 A being fixedly locked to the locking section  31  by means of the locking element  312 , in which the inner gear ring  33  is fixedly installed onto the inner wall of the accommodation section  32 A, with the motor  1  and gear set  2  being placed within the accommodation section  32 A and the cover  34  being fixedly locked to the accommodation section  32 A by using the locking element  341 . Each of the planetary gears  22  simultaneously engages with both the solar gear  23  and the inner gear ring  33  such that the accommodation section  32 A can be linked to rotate through the inner gear ring  33  when these planetary gears  22  rotate, further in turn bringing the case  3  to rotate so as to allow the case  3  to rotate relatively to the spindle  13 A of the motor  1 . Besides, the locking section  31  can be installed with a plurality of through holes  313  for lessening the weight of the case  3  in order to adjust power balance as the roller  103  rotates, thereby achieving the most stable and effective power output. Next, referring then to  FIG. 7 , in a fourth preferred embodiment of the instant disclosure, the accommodation section  32 A at the both ends of the case  3  is respectively installed with a motor  1  for increasing output power of the roller. 
     Refer subsequently to  FIG. 8 , in a fifth preferred embodiment of the instant disclosure as shown, when the motor  1  and the gear set  2  are placed in the accommodation space  32  within the case  3 , the motor axle  131 A of the motor  1  is set on the roller axle  133 A inside of the case  3  and the linking element  132 A is used to clip in connection to the roller axle  133 A thus also achieving the same effect. 
     Refer next to  FIG. 9 , in a sixth preferred embodiment of the instant disclosure as shown, suppose that the motor  1  and the gear set  2  are placed in the accommodation space  32  external to the case  3 , the spindle  13 B is now formed by connecting the motor axle  131 B of the motor  1  with the roller axle  132 B inside of the case  3 , with motor axle  131 B acting as the rotation center axle of the motor  1  and the roller axle  132 B being the rotation center axle of the case  3 , thus also achieving the same effect. 
     In summary, the instant disclosure is allowed to provide the following features: 
     1. since the motor  1  and the gear set  2  are installed inside or outside of the case  3 , the power generated by the motor  1  can bring the case  3  to rotate directly through the engagement between the gear set  2  and the inner gear ring  33 . The case  3  can thus actively rotate without additional use of belt, hence advantageously lessening motor  1  output power losses which may occur during transfer. Besides, simplified roller  103  structure also facilitates reduction of manufacture cost; 
     2. as the motor  1  operates, the output power from motor  1  enables the power output section  14  to rotate, thereby linking the solar gear  23  so in turn the planetary gear  22 , further together generating rotations of the inner gear ring  33  and the case  3 . In this way, by means of the tooth number ratio between the solar gear  23  and the planetary gear  22 , the output power from the motor  1  can be amplified in multiples, efficiently transferred to the case  3  so as to increase the performance of the motor  1 ; 
     3. the motor  1  can be as demand installed inside or outside of the case  3 , so it needs not to reserve space in advance for placement of the motor  1 , thereby effectively scaling down the area required for installation of the treadmill  10 , improving convenience in use and facilitating easy transportation. 
     The aforementioned texts illustrate only the preferred embodiments of the instant disclosure rather than limiting the scope of the instant disclosure thereto; all effectively equivalent changes, modifications and substitutions made in accordance with the present disclosure and appended drawings are deemed as being included in the instant disclosure defined by the following claims.