Abstract:
A tape loading apparatus comprises a base, a roller post about which a tape is wrapped for tape loading, and a carrying member for carrying the roller post. The roller post includes a rotation shaft and a roller rotating about the rotation shaft, and a shaft engagement member is provided on the base for holding the roller post at a predetermined position, the shaft engagement member directly contacting and pressing one or both ends of the rotation shaft.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates to a tape loading apparatus.  
           [0003]    2. Description of the Related Art  
           [0004]    Recently, in tape loading mechanisms for use in magnetic recording/reproduction apparatuses in which a tape is withdrawn out of a cassette and then wrapped about a rotary head cylinder, the position in the plane, and the height and inclination of a roller post provided on a carrying member are determined by pressing the carrying member to a positioning member provided on a chassis by a reference surface of the chassis and a pressing member.  
           [0005]    Hereinafter, a conventional tape loading apparatus will be described with reference to Japanese Laid-Open Publications Nos. 4-318361 and 4-318356.  
           [0006]    First, a conventional structure will be described with reference to Japanese Laid-Open Publication No. 4-318361. In this publication, FIG. 5 is a partial perspective view of a loading mechanism. Reference numerals  8 ,  10  and  11  indicate roller posts disposed on boats  14  and  15 . Reference numeral  86  and  87  indicate stoppers provided on the chassis. Reference numeral  41  indicates a feed side ring gear (a take-up side loading ring is not shown in FIG. 5, see FIG. 6). Reference numerals  53  and  55  indicate, respectively, feed side and take-up side drive shafts provided on the respective feed side and take-up side ring gears. Reference numerals  17  and  18  indicate feed side and take-up side loading guides, respectively.  
           [0007]    The feed side and take-up side loading rings are rotated by driving means. The boats  14  and  15  which are engaged with the respective feed side and take-up side loading rings are moved along the loading guides  17  and  18  to withdraw a tape out of a cassette for the purpose of tape loading. After completion of the loading, the boats  14  and  15  are pressed to the respective stoppers  86  and  87  to position the roller posts  8 ,  10  and  11 .  
           [0008]    The mechanism for positioning the boats  14  and  15  when the tape loading is completed will be described with reference to FIG. 15 of Japanese Patent No. 4-318361.  
           [0009]    [0009]FIG. 15 of the above-described publication shows a mechanism for positioning the feed side boat  14 . FIGS.  15 ( a ),  15 ( b ),  15 ( c ) and  15 ( d ) are a plan view, a side elevation view, a bottom plan view and a partial cross-sectional view, respectively. For the sake of clarification, the structure of each component is simplified.  
           [0010]    In this figure, reference numeral  86  indicates a stopper provided on a chassis  1 . A cone-like pressing portion  86   b  is provided on an upper portion of a pin  86   a . Reference numeral  14   a  is a V-shaped groove provided at a front end of a feed side boat  14 , which has a sloped portion. The feed side boat  14  is further provided with reference surfaces at the front and rear end portions thereof. The reference surfaces of the feed side boat  14  contacts and presses the reference surface of the chassis  1  when loading is completed, thereby making it possible to perform high-precision positioning.  
           [0011]    As shown in FIGS. 5 and 15 in the above-described publication, as the feed side ring gear  38  is rotated, the feed side boat  14  is guided along the feed side loading guide  17 . After completion of loading, the feed side boat  14  is in a position such that the stopper  86  contacts and presses the V-shaped groove  14   a . A driving force is constantly exerted on the feed side boat  14  by a driving means (a shaking plate  45 , not shown in FIGS. 5 and 15,) via a feed side drive shaft  53  in a direction indicated by P. Therefore, the stopper  86  contacts and presses the V-shaped groove  14   a , so that the V-shaped groove  14   a  constrains the lateral position of the feed side boat  14 . Meanwhile, a force is exerted to the feed side boat  14  in a direction indicated by F, so that the reference surfaces provided on the feed side boat  14  contact and press the reference surface provided on the chassis  1 , thereby constraining the back-and-forth and up-and-down position of the feed side boat  14 .  
           [0012]    Next, a method for adjusting the height of the roller post will be described with reference to Japanese Laid-Open Publication No. 4-318356, since Japanese Laid-Open Publication No. 4-318361 does not describe this method.  
           [0013]    In this publication, FIGS. 3, 4 and  5  are partial views of a conventional boat and roller post. FIG. 4 is an enlarged sectional view of FIG. 3 viewed from arrow A. In FIG. 4, reference numeral  17  indicates a roller holding member. The roller holding member  17  holds a roller  16  through which a shaft  16  is passed. Reference numeral  18  is a pipe which is press-fit into a take-up side boat  10  and into which the tip of the shaft  16  is inserted.  
           [0014]    [0014]FIG. 5 is a partial cross-sectional view of FIG. 4 viewed in a direction indicated by arrow B. In FIG. 5, the shaft  16  is pressed by the tip of a screw  19  engaged with a screw hole  20  provided at an end of the take-up side boat  10  toward the internal surface of the pipe  18  (reference surface), so that the shaft  16  does not spontaneously rotate. In order to fix securely the shaft  16  to the reference surface n with the tip of the screw  19 , the shaft  16  is extended to some extent below a point to which the tip of the screw  19  is pressed. In this case, the pipe  18  is extended a length of h below the bottom surface of the take-up side boat  10 . With this reference surface n, the inclination of the roller post with respect to the reference surface of the take-up side boat  10  is determined, so that a very high degree of dimensional precision is required for the pipe  18 .  
           [0015]    As described above, in conventional mechanisms, the height of a roller post is generally adjusted by shifting the roller post up and down in the following manner. A roller holding member  17  is rotated so that a screw  19  provided at an end of the shaft  16  integrated with the roller holding member  17  is engaged with a screw provided in the pipe  18  integrated with a take-up boat  10 .  
           [0016]    However, there are the following problems with the above-described conventional structures.  
           [0017]    As to the positioning mechanism described in the above-described Japanese Laid-Open Publication No.  4 - 318361 , the boats  39  and  40  are positioned with respect to the chassis  1  so that the position and inclination of the roller post are determined. For this reason, the position of the roller post with respect to each boat and the inclination of the roller post with respect to the reference surface of each post need to be secured with great precision. To this end, each boat needs to have an accurate and complicated shape and is therefore very expensive.  
           [0018]    As to the roller post height adjusting mechanism as described in the above-described Japanese Laid-Open Publication No. 4-318356, screws need to be formed in particular components, such as the roller post holding member  17  and the pipe  18 . Not only the number of parts is increased, but also the cost of each component is increased.  
           [0019]    As described in this publication, the pipe  18  is press-fit onto the take-up side boat  10 . A shaft  16  of the roller post is provided inside the pipe  18  with reference to the reference surface n so that the inclination of the roller post is determined. Thus, the inclination of the roller post is determined via a number of components. Therefore, in order to secure the inclination precision of the roller post with respect to the chassis  1 , the precision of each component needs to be greatly secured, resulting in an increase in the costs of the components.  
           [0020]    If the inclination precision and position of the roller post depart from that intended with respect to the boat, the running of a tape immediately incurs problems, which may cause damage in the tape. As described above, in the conventional loading mechanism, the number of components is large and a high degree of precision is required for each component. Thus, cost reduction of the mechanism is prevented and it is difficult to achieve quality of the tape loading apparatus.  
         SUMMARY OF THE INVENTION  
         [0021]    According to one aspect of the present invention, a tape loading apparatus comprises a base, a roller post about which a tape is wrapped for tape loading, and a carrying member for carrying the roller post. The roller post includes a rotation shaft and a roller rotating about the rotation shaft, and a shaft engagement member is provided on the base for holding the roller post at a predetermined position, the shaft engagement member directly contacting and pressing one or both ends of the rotation shaft. Therefore, a simple mechanism for positioning a roller post can be made of inexpensive components, and the number of components can be reduced, thereby providing an inexpensive and highly reliable tape loading apparatus.  
           [0022]    In one embodiment of this invention, at least one V-shaped cut is provided in the shaft engagement member, and the at least one V-shaped cut engage a respective end of the rotation shaft. Therefore, the roller post can be fixed at a predetermined position with great precision. A tape loading apparatus can be easily obtained using more simple and inexpensive components.  
           [0023]    According to another aspect of the present invention, a tape loading apparatus comprises a roller post about which a tape is wrapped for tape loading, a rotation shaft about which the roller post is rotatably secured, the rotation shaft having a lower portion extending from a lower end of the roller post and an upper portion extending from an upper end of the roller post, a carrier member to which the lower portion of the rotation shaft is secured, a pushing mechanism for pushing on the carrier member to move the carrier member generally horizontally for tape loading, a lower member extending toward the roller post, the lower member including a lower engagement surface for securely engaging the lower portion of the rotation shaft at a lower portion fixed horizontal position as a result of force exerted by the pushing mechanism, an upper member extending toward the roller post, the upper member including an upper engagement surface for securely engaging the upper portion of the rotation shaft at an upper portion fixed horizontal position as a result of the force exerted by the pushing mechanism, and a ceiling member including a ceiling engagement surface for securely engaging a tip of the upper portion of the rotation shaft at an upper ceiling fixed vertical position as a result of the force exerted by the pushing mechanism.  
           [0024]    In one embodiment of this invention, the lower member and the upper member each include a V-shaped cut to form the lower and upper engagement surfaces.  
           [0025]    In one embodiment of this invention, the lower member, upper member and ceiling member are formed by a single integral structure.  
           [0026]    In one embodiment of this invention, the lower member, upper member and ceiling member are generally parallel to one another.  
           [0027]    Thus, the invention described herein makes possible the advantages of providing a tape loading apparatus having a loading mechanism comprising a small number of simple components. Cost can thereby be reduced while a high level of performance is achieved.  
           [0028]    These and other advantages of the present invention will become apparent to those skilled in the art upon reading and understanding the following detailed description with reference to the accompanying figures. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0029]    [0029]FIGS. 1A, 1B and  1 C are views showing a tape loading apparatus according to an example of the present invention. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
     EXAMPLE  
       [0030]    A tape loading apparatus according to an example of the present invention will be described with reference to FIGS. 1A to  1 C.  
         [0031]    [0031]FIG. 1A is a side view showing a mechanism for positioning a roller post at a place for tape loading. In FIG. 1A, reference numeral  4  indicates a boat for shifting a roller post  6   b . A rotation shaft  6   a  of the roller post  6   b  is press-fit into the boat  4 . In the roller post  6   b , reference numeral  6   d  indicates a portion of the rotation shaft  6   a  protruding above an upper flange  6   f  of the roller post  6   b . Reference numeral  6   a  indicates a portion of the rotation shaft  6   a  protruding below the lower flange  6   g  of the roller post  6   b . Therefore, the portions  6   a  and  6   d  are the respective upper and lower portions of the rotation shaft  6   a.    
         [0032]    Reference numeral  7  indicates a guide member of the boat  4  in loading. Reference numeral  100  indicates a chassis. A roller post positioning member  17  (hereinafter referred to as a V-shaped stopper) is attached to a vertical wall  100   a  of the chassis  100  with a screw  18 . The V-shaped stopper  17  comprises a lower V portion  17   a  which contacts and presses the lower portion  6   a  of the roller post  6   b , an upper V portion  17   b  which contacts and presses the upper portion  6   d  of the roller post  6   b , and a ceiling portion  17   d  which contacts and presses the tip  6   e  of the roller post  6   b , so that the V-shaped stopper  17  positions the roller post  6   b . FIG. 1B is a view showing the upper portion of the V-shaped stopper  17 , taken along line C-C in FIG. 1A. FIG. 1C is a view showing the lower portion of the V-shaped stopper  17 , viewed in a direction indicated by arrow D. Portions  17   g  and  17   e  are resilient, and are bent in the respective directions of arrows A and B, to which adjusting screws  19  and  20  are attached. By rotating the screw  19 , the position of the lower V portion  17   a  is changed. By rotating the screw  20 , the ceiling portion  17   g  and the height of a point  17   d  which contacts the tip  6   e  of the roller post  6   b  can be adjusted.  
         [0033]    The operation of the thus-constructed tape loading apparatus will be described with reference to FIGS. 1A to  1   c.    
         [0034]    In FIGS. 1A to  1 C, the boat  4  is pushed substantially in a direction indicated by arrow E 1  by a driving means (not shown). As a result, the lower portion  6   c  of the roller post  6   b  contacts and presses the lower V portion  17   a . The upper portion  6   d  of the roller post  6   b  contacts and presses the upper V portion  17   b . Therefore, the tip  6   e  contacts and presses the ceiling portion  17   d . Forces are exerted on the roller post  6   b  in directions indicated by arrows E 1 , E 2  and E 3  so that the roller post  6   b  is positioned at a predetermined angle and height.  
         [0035]    In this case, as described above, the V-shaped stopper  17  is adjusted in the directions of arrows A and E 1 , E 2  and E 3  so that each portion is held at an ideal position by the screws  19  and  20  with respect to the chassis  100 . The rotation shaft  6   a  of the roller post  6   b  is directly pushed and attached to the upper and lower V portions  17   a  and  17   b  and the ceiling portion  17   d  without other members therebetween. Therefore, the roller post  6   b  is positioned with great precision. As shown in FIG. 1A, when the position of the boat  4  is established for tape loading, the boat  4  does not contact and press any of the chassis  100 , the guide member  7  and the V-shaped stopper  17 . Thus, the boat  4  does not affect the precision of positioning the roller post  6   b . In other words, the position and inclination of the boat  4  do not affect the position precision of the roller post  6   b , unlike conventional technologies. Therefore, a high degree of precision with respect to the dimensions of the boat  4  and the position and inclination of the roller post  4   b  with respect to the boat  4  are not required, and substantially ideal tape loading can be achieved. As a result, since a high degree of precision is not required for each component, the cost of each component can be reduced while the precision of positioning each component can be easily obtained. Therefore, a highly reliable tape loading apparatus can be obtained.  
         [0036]    Further, in the example, the height of the roller post  6   b  is adjusted by adjusting the height of the ceiling portion  17   d  which the tip  6   e  of the roller post  6   b  contacts and presses. Therefore, as described in the DESCRIPTION IN THE RELATED ART, the screw provided in the roller post, the pipe press-fit into the boat, the screw provided in the pipe, and the like are not required. This makes it possible to reduce the number of components and eliminate expensive components.  
         [0037]    As described above, according to the example of the present invention, the boat  4  carrying the roller post  6   b  is pushed from the rear to cause the rotation shaft  6   a  of the roller post  6   b  to contact directly the positioning members so as to position the roller post  6   b . Therefore, a simple mechanism for positioning a roller post can be made of inexpensive components, and the number of components can be reduced, thereby providing an inexpensive and highly reliable tape loading apparatus.  
         [0038]    Further, due to the V-shaped cuts of the V-shaped stopper  17  which contact and press the respective upper and lower portions of the roller post  6   b  to position the roller post  6   b , the roller post  6   b  can be fixed at a predetermined position. Therefore, a tape loading apparatus can be easily obtained using simple and inexpensive components.  
         [0039]    In the example, the V-shaped stopper  17  which is engaged with the rotation shaft  6   a  is directly attached to the chassis  1 . Even if the V-shaped stopper  17  is attached to the chassis  1  via a third member, the same effect as that of the present invention can be obtained. Further, even if the V-shaped stopper  17  is integrated as part of the chassis  1 , the same effect as that of the present invention can be obtained.  
         [0040]    As described above, according to the present invention, an engagement member carried by a base is used to position directly one or both ends of the rotation shafts of a roller post, thereby making it possible to provide an inexpensive and high-performance tape loading apparatus having a positioning mechanism comprising simple components.  
         [0041]    Various other modifications will be apparent to and can be readily made by those skilled in the art without departing from the scope and spirit of this invention. Accordingly, it is not intended that the scope of the claims appended hereto be limited to the description as set forth herein, but rather that the claims be broadly construed.