Patent Publication Number: US-10328744-B2

Title: Motor fixing structure of engraving machine

Description:
NOTICE OF COPYRIGHT 
     A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to any reproduction by anyone of the patent disclosure, as it appears in the United States Patent and Trademark Office patent files or records, but otherwise reserves all copyright rights whatsoever. 
     BACKGROUND OF THE PRESENT INVENTION 
     Field of Invention 
     The present invention relates to a motor fixing structure of an engraving machine, and more particularly to a lifting platform having at least three clamping blocks for quickly locking various sized motors. 
     Description of Related Arts 
     As shown in  FIG. 1  to  FIG. 5 , a conventional engraving machine includes a platform  11  suspended in a mounting trough  2  of a worktable  1 . The platform  11  has a blade hole  111  and a receiving hole  113  for insertion of a wrench  112 . A plurality of screw rods  12  is vertically provided under the bottom surface of the platform  11 . The screw rods  12  are arranged in parallel with each other. The blade hole  111  is located among the screw rods  12 . A lifting platform  13  is located under the platform  11 . The lifting platform  13  is provided with pivot holes  131  corresponding in position to the screw rods  12 . Each pivot hole  131  is provided with a screw seat  132  for engagement of the screw rod  12 . The lifting platform  13  has a connecting hole  133  corresponding in position to the receiving hole  113 . The connecting hole  133  is mounted with a rotatable shaft seat  134 . Each of the screw seats  132  and the shaft seat  134  is provided with a sprocket  135 . The sprockets  135  are connected by a chain  16 . The lifting platform  13  has a through hole  136  corresponding in position to the blade hole  111  and screws  137  around the through hole  136 . The bottom end of each screw  137  is connected with a press plate  138 . Through the press plates  138  screwed to the screws  137 , the bottom surface of the lifting platform  13  is mounted with a jig  14 . The jig  14  has a plurality of screw holes  141  spaced at a different interval for mounting a motor  15  which may be different in size to the bottom surface of the lifting platform  13 . A rotary shaft  151  of the motor  15  is provided with a cutter  152 . When the sprocket  135  of the shaft seat  134  is rotated by the wrench  112 , the sprockets  135  of the screw seats  132  are rotated through the chain  16  so that the lifting platform  13  is lifted and lowered along the screw rods  12  to adjust the height that the cutter  152  of the motor  15  extends out of the blade hole  111  for engraving the wood. However, the above structure has the following problems: 
     1. The screw holes  141  of the jig  14  are spaced at a different interval for mounting various sized motors  15  to the bottom surface of the lifting platform  13 . For mounting the motor  15 , it is necessary to use other tools. It is not convenient when the engraving machine  10  needs replacing a motor  15  with a different speed or power. 
     2. The motor  15  is mounted to the suitable screw holes  141  according to its size, but it is not sure whether the rotary shaft  151  of the motor  15  is located at the center of the lifting platform  13 . Even if the cutter  152  is only slightly deviated, the precision and accuracy of engraving the wood may be affected. 
     Accordingly, the inventor of the present invention has devoted himself based on his many years of practical experiences to solve these problems. 
     SUMMARY OF THE PRESENT INVENTION 
     The primary object of the present invention is to solve the aforesaid problems and to provide a motor fixing structure of an engraving machine. A lifting platform of the engraving machine has a circular through hole, at least three protruding walls spaced and arranged around the through hole, and notches each defined between every adjacent two of the protruding walls. A clamping block is provided in the vicinity of each notch, which is movable in a radial direction. The protruding walls are fitted with a turning disc. The turning disc has oblique curved holes each corresponding in position to the clamping block. A quick release assembly is inserted in a corresponding one of the oblique curved holes and the clamping block to be connected to the lifting platform for tightening or loosening the clamping block. The turning disc is driven by a drive rod to rotate, so that the oblique curved holes are rotated and displaced to move the clamping blocks inward or outward. With the above-described structure, the motor can be quickly assembled or disassembled. The present invention is used for mounting various sized motors. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a conventional engraving machine; 
         FIG. 2  is a front perspective view of a conventional lifting platform; 
         FIG. 3  is a bottom perspective view of the conventional lifting platform; 
         FIG. 4  is a sectional view of the conventional lifting platform mounted to a worktable; 
         FIG. 5  is a perspective view of the present invention; 
         FIG. 6  is a front perspective view of the lifting platform of the present invention; 
         FIG. 7  is a perspective view of the lifting platform mounted with the motor of the present invention; 
         FIG. 8  is a top sectional view of the present invention, showing that the clamping blocks are moved outward to release the motor; 
         FIG. 9  is a side sectional view of the present invention, showing that the clamping blocks are moved outward to release the motor; 
         FIG. 10  is a top sectional view of the present invention, showing that the clamping blocks are moved inward to clamp the motor; and 
         FIG. 11  is a side sectional view of the present invention, showing that the clamping blocks are moved inward to clamp the motor. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings. 
     Referring to  FIG. 5  to  FIG. 11 , a peripheral portion of a lifting platform  20  of an engraving machine is provided with a plurality of pivot holes  201 . The lifting platform  20  is provided with a circular through hole  202 , at least three protruding walls  21  extending downward from the through hole  202  and arranged around the through hole  202 , and notches  211  each defined between every adjacent two of the protruding walls  21 . A bottom surface of the lifting platform  20 , corresponding in position to the outer sides of the notches  211 , is provided with engaging portions  22  each having a pair of rail grooves  221  at two sides thereof. The engaging portion  22  is provided with a radial guide hole  222  penetrating the lifting platform  20 . The bottom surface of the lifting platform  20  is provided with an adjustment seat  23  protruding downward between every two of the engaging portions  22  and close to a corresponding one of the protruding walls  21 . The adjustment seat  23  has a transverse perforation  231 . The engaging portion  22  is connected with a clamping block  24 . Two sides of the clamping block  24  are provided with side flanges  241  to be movably engaged in the rail grooves  221 , so that the clamping block  24  can be reciprocated back and forth in the engaging portion  22 . The clamping block  24  has a clamping surface  242  facing the notch  211  and an aperture  243  vertically penetrating the clamping block  24  and corresponding in position to the guide hole  222 . The protruding walls  21  are fitted with a turning disc  25 . The turning disc  25  has a central fitting hole  251  and is rotatably connected to the protruding walls  21 . The turning disc  25  is provided with at least three oblique curved holes  252  each corresponding in position to the aperture  243  and the guide hole  222 . The turning disc  25  further has a shaft hole  253 . The shaft hole  253  is pivotally connected with a shaft  26 . The shaft  26  has a head portion  261  and a shaft rod  262 . A lower end of the shaft rod  262  is formed with a threaded portion  263 . The shaft rod  262  is inserted in the shaft hole  253  from the top of turning disc  25 , and a nut  264  is screwed to the threaded portion  263  at the lower end of the shaft rod  262 . The head portion  262  is provided with a transverse screw hole  265  corresponding in position to the perforation  231 . A drive rod  27  is inserted through the perforation  231  and screwed to the screw hole  265  of the head portion  261  of the shaft  26 . The drive rod  27  includes a drive head  271  and an adjustment screw rod  272 . After the adjustment screw rod  272  is inserted through the perforation  231 , a positioning nut  273  is screwed to the adjustment screw rod  272  so that the adjustment seat  23  is sandwiched between the drive head  271  and the positioning nut  273 . The drive rod  27  is idle in the perforation  231  to screw the shaft  26  to turn the turning disc  25 . A top surface of the lifting platform  20  is provided with limit grooves  28  each corresponding in position to the guide hole  222 . The limit grooves  28  are arranged radially and have a rectangular shape. A quick release assembly  29  is inserted in a corresponding one of the oblique curved holes  252 , the aperture  243  of the clamping block  24 , and the guide hole  222  of the lifting platform  20 . The quick release assembly  29  includes a rod  291 , a threaded section  29  at a top end of the rod  291 , and an eccentric lever  293  at a bottom end of the rod  291 . A square locking block  294  having a threaded hole  295  is provided in each of the limit grooves  28 . The locking block  294  is slidable in the limit groove  28  but can not be rotated. The rod  291  is inserted from the bottom surface of the turning disc  25  to pass through the oblique curved hole  252 , the aperture  243  and the guide hole  222 , and is screwed to the threaded hole  295  of the locking block  294 . The locking block  294  is unable to rotate, so that the eccentric lever  293  at one end of the quick release assembly  29  is rotated to connect the rod  291  with the threaded hole  295  of the locking block  294 . The eccentric lever  293  may be pulled to tighten or loosen the clamping block  24 . According to the above-described structure, the shaft  26  is rotated by rotating the drive rod  27  to turn the turning disc  25 , thereby displacing the oblique curved hole  252  to move the rod  291  of the quick release assembly  29  in the guide hole  222 , so that the clamping blocks  24  can be synchronously moved inward or outward to clamp or release a different sized motor. 
     The assembly, function and the details of the above-described embodiment are described hereinafter. Referring to  FIG. 5  to  FIG. 11 , in this embodiment, the oblique curved holes  252  are evenly arranged on the turning disc  25  counterclockwise. When the motor  15  is mounted in the through hole  202  and the fitting hole  251 , the turning disc  25  is driven to rotate clockwise. The aperture  243  makes the rod  291  to be perpendicular to the clamping block  24 . The rods  291  which are only radially movable in the oblique curved holes  252  are brought to the inner side of the turning disc  25 , and the rods  291  drive the clamping blocks  24  to synchronously clamp the motor  15 . On the contrary, when the turning disc  25  is driven to rotate counterclockwise, the rods  291  which are only radially movable in the oblique curved holes  252  are brought to the outer side of the turning disc  25 , and the rods  291  drive the clamping blocks  24  to synchronously release the motor  15 . The clamping blocks  24  synchronously clamp the motor  15 , so the cutter  152  of the motor  15  is located at the center of the through hole  202 . That is, the cutter  152  of the motor  15  can be easily mounted in the central position, thereby providing better precision and accuracy for engraving the wood. When it is necessary to replace a different sized motor  15 , the eccentric lever  293  of the quick release assembly  29  is pulled to be in a non-tightened state to loosen the clamping block  24 . The drive head  271  of the drive rod  27  is turned to drive the shaft  26 , and then the shaft  26  drives the turning disc  25  to turn counterclockwise, while, the shaft  26  is rotated to cooperate with the direction of the adjustment screw rod  272 . The diameter of the perforation  231  is greater than that of the adjustment screw rod  272 . The perforation  231  is in the form of an elongate hole to provide a sufficient space for the drive rod  27  to cooperate with the shaft  26 . The turning disc  25  is rotated counterclockwise so that the oblique curved holes  252  bring the rods  291  of the quick release assemblies  29  and the clamping blocks  24  to the outer side of the turning disc  25  (as shown in  FIG. 8  and  FIG. 9 ). The clamping surfaces  242  of the clamping blocks  24  are synchronously moved away from the through hole  202  to release the motor  15  for the replacement of another motor. After the motor is replaced, the drive head  271  of the drive rod  27  is rotated to drive the shaft  26  so that the shaft  26  drives the turning disc  25  to rotate clockwise. The oblique curved holes  252  of the turning disc  25  bring the rods  291  of the quick release assemblies  29  and the clamping blocks  24  to the inner side of the turning disc  25  (as shown in  FIG. 10  and  FIG. 11 ), so that the clamping surfaces  242  of the clamping blocks  24  synchronously clamp the motor  15 . The larger the rotational angle of the turning disc  25  is, the greater the displacement of the clamping blocks  24  is. Therefore, it is only required to adjust the rotational angle of the turning disc  25  so that the present invention is used for mounting various sized motors. Finally, the eccentric lever  293  of the quick release assembly  29  is pulled to be in a tightened state to secure the clamping block  24  in a quick manner. 
     Although particular embodiments of the present invention have been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the present invention. Accordingly, the present invention is not to be limited except as by the appended claims.