Abstract:
A rotatable connection apparatus is disclosed including: a roller coupled to an object to be rotated, wherein the roller rotates with the rotation of the object; a frictional component for contacting a surface of the roller to provide a friction for fixing the object in a first position when the object is rotated to the first position; and an elastic component having a terminal coupled to the frictional component and another terminal coupled to an fixed position, wherein the elastic component is deformed to adjust the friction between the roller and the frictional component when the object is rotated to the first position.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present disclosure relates to a connection apparatus, and more particularly, to a rotatable connection apparatus that utilizes an elastic component to adjust the friction between a roller and a frictional component so as to fix an object to be rotated in a certain position.  
         [0003]     2. Description of the Prior Art  
         [0004]     In practical applications, many products (e.g., some cell phones, scanners, or copy machines) are provided with a cover or a similar part, so that the user can open the cover while uses the product and close the cover to protect important components of the product or against dust when the product is not in use. The cover is typically connected to the main body of the product through a connection apparatus. The connection apparatus must be a rotatable connection apparatus so that the user can freely open or close the cover.  
         [0005]     The conventional rotatable connection apparatuses can be divided into two groups, one is realized by using a combination of a rotating shaft and a hole, or a combination of a groove and a pillar, another is realized by using multiple components (e.g., a gear set) to connect the cover to the main body of the product. Typically, the conventional approaches can only provide an ordinary function similar to a rotating shaft, i.e., to make the cover to be rotatable. In many applications, the user not only needs to rotate the cover but also wants to fix the cover in a certain position as his/her wish. That is, the cover has to immediately fix in the position where the user stops rotating the cover. However, the conventional approaches cannot achieve such a purpose.  
         [0006]     Take a copy machine as an example. The user needs to open the cover of the copy machine and then puts the document to be copied on a copy platform when uses the copy machine. Afterward, the user needs to close the cover so as to execute the copy function. When opening the cover, if the user moves his/her hand from the cover to do another movement or just carelessly loosens his/her hand from the cover, the gravity may cause the cover to rapidly close, especially in the case where the included angle between the cover and the copy platform is not large enough. The impact of the cover against the main body of the copy machine easily causes damage to the copy machine and may harm the user&#39;s fingers. To avoid above situation, the user needs to pay attention to the cover when rotates the cover. Obviously, this is very inconvenient for the user.  
       SUMMARY OF THE INVENTION  
       [0007]     It is therefore an objective of the present invention to provide a rotatable connection apparatus that is capable of fixing an object to be rotated in a certain position by adjusting a friction to solve the above-mentioned problems.  
         [0008]     An exemplary embodiment of a rotatable connection apparatus is disclosed comprising: a roller coupled to an object to be rotated, wherein the roller rotates with the rotation of the object; a frictional component for contacting a surface of the roller to provide a friction for fixing the object in a first position when the object is rotated to the first position; and an elastic component having a terminal coupled to the frictional component and another terminal coupled to an fixed position, wherein the elastic component is deformed to adjust the friction between the roller and the frictional component when the object is rotated to the first position.  
         [0009]     The rotatable connection apparatus of the present invention utilizes the elastic component to adjust the friction between the roller and the frictional component so that the object to be rotated (e.g., the cover of a copy machine, scanner, or a multi-function product) can be fixed in a predetermined position. Accordingly, the cover will not rapidly close after the user loosens his/her hand from the cover due to the moment caused by the gravity is balanced by the friction. As a result, the inconvenience of the conventional rotatable connection apparatus can be significantly improved.  
         [0010]     These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]      FIG. 1  is a schematic diagram illustrating a rotatable connection apparatus according to an exemplary embodiment of the present invention.  
         [0012]      FIG. 2  is a schematic diagram illustrating an example where a protrudent part of a cover of the rotatable connection apparatus of  FIG. 1  touches a sliding component.  
         [0013]      FIG. 3  is a schematic diagram illustrating that the cover of  FIG. 2  is rotated to a position where the distance between the sliding component and a roller reaches a maximum value.  
         [0014]      FIG. 4  is a schematic diagram illustrating an example where the protrudent part of the cover of  FIG. 3  is about to leave the sliding component. 
     
    
     DETAILED DESCRIPTION  
       [0015]     The rotatable connection apparatus of the present invention comprises a roller, a frictional component, an elastic component, a groove, and a sliding component. For the purpose of explanatory convenience in the following description, it is herein assumed that the rotatable connection apparatus of the present invention is employed as the cover hinge of a copy machine to connect the cover and the main body of the copy machine. In such an application, the cover can be fixed in a position where the user loosens his/her hand from the cover when opening or closing the cover.  
         [0016]     Please refer to  FIG. 1 , which shows a schematic diagram illustrating a rotatable connection apparatus  10  according to an exemplary embodiment of the present invention. The rotatable connection apparatus  10  comprises a roller  20 , a cover  30 , a flexible belt  40 , a spring  50 , a sliding component  60 , and a groove  70 . The bottom of the sliding component  60  is provided with a tenon  80  lodged in the groove  70  so that the sliding component  60  is able to freely slide along the groove  70 . In this embodiment, the cover  30  is the object to be rotated, the flexible belt  40  is employed as a frictional component, and the spring  50  is employed as an elastic component. In addition, the roller  20  is arranged on the cover  30  and can rotate with the rotation of the cover  30 . Please note that the cover  30  is in a close state in  FIG. 1 , i.e., the included angle between the cover  30  and the platform of the copy machine (not shown) is zero degree. At that moment, a protrudent part of the cover  30  does not contact to the sliding component  60 . Accordingly, the sliding component  60  is at an initial position. On the other hand, the flexible belt  40  surrounds the surface of the roller  20  as illustrated in  FIG. 1 . One terminal of the flexible belt  40  is fixed in a fixed point S whose position is not changed when the cover  30  rotates. Another terminal of the flexible belt  40  is connected to the sliding component  60  via the spring  50 . When the sliding component  60  is at the initial position, the spring  50  has a natural length, i.e., the spring  50  is not stretched.  
         [0017]     When the user wants to open the cover  30 , the user needs to apply a force to the cover  30  so as to drive the cover  30  to rotate. As can be derived from the foregoing descriptions, there is a contact surface between the flexible belt  40  and the roller  20 . According to the friction law, when the roller  20  rotates with the rotation of the cover  30 , a friction is generated between the flexible belt  40  and the roller  20 , and the active direction of the friction is opposite to the rotation direction of the roller  20 . In this embodiment, the materials of the roller  20  and the flexible belt  40  are selected and related mechanism is properly designed to avoid the rotation of the cover  30  from being influenced by the friction on the roller  20  before the protrudent part of the cover  30  touches the sliding component  60 .  
         [0018]     Please refer to  FIG. 2 , which shows a schematic diagram illustrating an example where the protrudent part of the cover  30  touches the sliding component  60 . In contrast to the  FIG. 1 , the cover  30  in  FIG. 2  is opened to a certain position, and the protrudent part of the cover  30  touches the sliding component  60  at a point P. Since the sliding component  60  is still at the initial position, the spatial relationship between the sliding component  60  and the roller  20  is not changed. Accordingly, the spring  50  still has a natural length, and the friction between the flexible belt  40  and the roller  20  is the same as that illustrated in  FIG. 2 . However, if the cover  30  continues to rotate toward a direction A, the protrudent part of the cover  30  pushes the sliding component  60  to move toward a direction B along the groove  70 . Since the moving direction B of the sliding component  60  is a direction away from the roller  20 , the sliding component  60  stretches the spring  50 . Therefore, the spring  50  deforms and generates an elastic force. The elastic force stretches the flexible belt  40  so that the flexible belt  40  surrounds the roller  20  tighter than the case shown in  FIG. 1 . Accordingly, the friction between the flexible belt  40  and the roller  20  is greater than that before the protrudent part of the cover  30  pushing the sliding component  60  to move along the groove  70 . By proper design, a moment on the roller  20  caused by the weight of the cover  30  can be balanced off by an opposite moment on the roller  20  caused by the friction at the time the cover  30  rotates to a first position. In other words, if the cover  30  stops rotating at the first position, the cover  30  will fix on the first position and does not close by the gravity.  
         [0019]     It can be derived from the physical property of the spring  50  that the deformation of the spring  50  and the pulling force applied on the flexible belt  40  both increase as the distance between the sliding component  60  and the roller  20  increases. As described previously, the flexible belt  40  is flexible due to it is made by flexible materials. Accordingly, when the pulling force applied on the flexible belt  40  increases, the flexible belt  40  surrounds the roller  20  tighter and results in greater friction. Similarly, the moment on the roller  20  caused by the friction also increases correspondingly. If the friction is too large, the rotation smoothness of the cover  30  may be affected. In such a situation, the user needs to use more strength to open the cover  30 . To avoid this, a proper mechanism design is employed in the present invention so that the moment caused by the gravity can be balanced off by the moment caused by the friction when the distance between the sliding component  60  and the roller  20  reaches a maximum value while maintaining the rotation smoothness of the cover  30 .  
         [0020]     Please refer to  FIG. 3 , which shows that the cover  30  of  FIG. 2  is rotated to a position where the distance between the sliding component  60  and the roller  20  reaches a maximum value. When the cover  30  rotates to a second position as illustrated in  FIG. 3 , the distance between the sliding component  60  and the roller  20  reaches a maximum value, and the protrudent part of the cover  30  touches the sliding component  60  at a point Q. At that time, the deformation of the spring  50  and the pulling force applied on the flexible belt  40  both reach a maximum level. Additionally, the friction between the flexible belt  40  and the roller  20  also reaches a maximum value when the cover  30  rotates to the second position. If the cover  30  continues to rotate toward a direction C, the protrudent part of the cover  30  does not push the sliding component  60  to move away from the roller  20  any more. Instead, the sliding component  60  moves toward a direction D along the groove  70  by the pulling force of the spring  50 . The pulling force applied on the flexible belt  40  then decreases as the deformation of the spring  50  decreases. Accordingly, the friction between the flexible belt  40  and the roller  20  also decreases correspondingly. At that moment, since there is a considerable included angle between the cover  30  and the horizontal plane, the moment on the roller  20  caused by the weight of the cover  30  is not as large as that in the previous cases. Thus, although the friction between the flexible belt  40  and the roller  20  is smaller than that in the previous cases, the moment on the roller  20  caused by the gravity can still be balanced off by the moment on the roller  20  caused by the friction. This also renders that the user can easily rotate the cover  30 .  
         [0021]     Please refer to  FIG. 4 , which shows a schematic diagram illustrating an example where the protrudent part of the cover  30  is about to leave the sliding component  60 . As illustrated in  FIG. 3 , if the cover  30  of the rotatable connection apparatus  10  continues to rotate toward the direction C, the deformation of the spring  50  gradually decreases until the spring  50  returns to the natural length, i.e., the sliding component  60  returns to the initial position. At that time, the cover  30  touches the sliding component  60  at a point R. If the user continues to rotate the cover  30 , the cover  30  will leave the sliding component  60 . As in the foregoing descriptions, the materials of the roller  20  and the flexible belt  40  are selected and related mechanism is properly designed to avoid the rotation of the cover  30  from being influenced by the friction on the roller  20  after the protrudent part of the cover  30  leaves the sliding component  60 . As the included angle between the cover  30  and the horizontal plane increases, the moment on the roller  20  caused by the gravity decreases. As a result, the user can open the cover  30  easier after the cover  30  leaves the sliding component  60 . In one aspect, the rotatable connection apparatus  10  of the present invention can speed up the rotation speed of the object to be rotated after the rotation angle exceeds a predetermined value. The cover  30  is typically regarded as full open when the included angle between the cover  30  and the copy platform of the copy machine (not shown) reaches 90 degrees. Generally, the copy machine is provided with a limiter to restrict the rotatable range of the cover  30  so that the included angle between the cover  30  and the copy platform of the copy machine cannot exceed 90 degrees.  
         [0022]     As in the foregoing embodiment, the entire operations of opening the cover  30  from it is completely closed to completely opened are described. The same principle can also be applied on the operations of closing the cover  30  from it is completely opened to completely closed. Additionally, the copy machine is merely an example of application rather than a restriction of the practical applications of the present invention. In practice, the disclosed rotatable connection apparatus  10  can be applied in various devices, such as scanners and multi-function products. Since the rotatable connection apparatus  10  is able to fix the cover  30  in any position where the user leaves his/her hand, the safety and convenience of using these devices can be significantly improved.  
         [0023]     Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims.