Patent Publication Number: US-11396090-B2

Title: Screw depth adjuster for driving screw to certain depth and method for driving screw to certain depth by using the same

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 screw depth adjuster, especially to a screw depth adjuster in which screws are positioned after being driven to the required depth from surfaces of workpiece/material for preventing damages on the surface of the workpiece/material and damages on the screw caused by being driven too much. 
     Description of Related Arts 
     Screw depth adjusters are well known to people skilled in the art, as revealed in US Pat. Pub. No. 20080289459, U.S. Pat. Nos. 5,235,327, 4,736,658, etc. Refer to US Pat. Pub. No. 20080289459, a screw/depth control driver device used for preventing the screw from driving beyond the depth required by users is revealed. The device has a free-spinning sleeve  17 . In order to achieve the above purpose, a device is provided to set and hold the amount of return by the sleeve before the torque driving the screw is released preventing the screw from being over-driven. The device further includes a screw driving device  12 , a depth control stop/setting nut  14  and a lock-retaining ring  16 . The screw driving device  12  has a thread pattern to allow the depth control stop  14  to be moved forward or backward and held along the screw driving device  12  to control the depth of the screw being driven. The sleeve  17  can rotate freely on the screw driving device  12 . The lock retaining ring  16  is unable to rotate when engaged over the depth control stop  14 . While in use, the depth control stop is rotated on the screw driving device to be fixed at a selected longitudinal position of the device. Then the lock retaining ring  16  is slid back over the depth control stop  14 . When the screw driving device is driven forward, the depth control stop comes to butt against the screw control sleeve so that the screw driving device cannot be driven forward any further and hence the screw cannot be driven forward any further. To use the device, the depth control stop  14 , the lock retaining ring  16  and the sleeve  17  are moved in turn. 
     In order to set a desired depth of the screw, the depth control stop  14  is first rotated clockwise/anti-clockwise. Then the lock retaining ring  16  is slid back over the depth control stop  14 . The sleeve  17  is then slid completely forward until a flared end is beyond. However, the position of the sleeve  17  during the driving is unable to learn in a real-time manner. Thus the depth control stop  14  has to be moved multiple times for adjustment. During each time of adjustment of the driving depth, the sleeve  17  needs to be moved first and then the lock retaining ring  16  is slid forward to disengage the depth control stop  14 , hence the depth control stop  14  can rotate and move for adjustment. Users can&#39;t learn whether the position of the sleeve  17  is correct for the desired depth of the screw while adjusting the depth control stop. Therefore the device is inconvenient to use. 
     Moreover, the screw/depth control driver device further includes two longitudinally-oriented grooves  30  and the lock retaining ring  16  has two protrusions  27  on opposite sides that fit into the longitudinally-oriented grooves  30  correspondingly. The above design has significant shortcomings. The power tools available on the market now provide greater rotary torsion. The most common range of rotary torsion is 150-240 Newton-meter (Nm) and the revolutions per minute (RPM) is ranging from 3200 to 3600. When the sleeve  17  is in contact with the workpiece, the IPM (impacts per minute) is 3500˜4000. The impact force acted on the sleeve  17  is returned to the depth control stop  14  so that the protrusions  27  and the longitudinally-oriented grooves  30  hit each other and cause deformation. The protrusions  27  of the depth control stop  14  are unable to move smoothly in the longitudinally-oriented grooves  30  once being deformed, and even easily locked in the grooves  30 . Thereby the depth control stop  14  can&#39;t be moved for adjustment. 
     Furthermore, the depth control stop  14  contains detent balls  28  each of which fit over a spring  15 . Thus the dent balls  28  can be elastically protruding from or popped in the depth control stop  14 . The lock retaining ring  16  has a groove on the inside designed  25  to allow the dent balls  28  set into the depth control drop  14  to be engaged into the lock retaining ring  16  to hold the lock retaining ring  16  into place over the depth control stop  14 . During adjustment, the depth control drop  14  needs to be rotated a circle until the dent balls  28  being mounted into the grove  25  correspondingly. There is a limit on the rotation of the depth control drop  14 —at least half a circle as one scale. Thereby the screw/depth control driver device  10  doesn&#39;t have fine-adjustment function. 
     Thus there is room for improvement and there is need to provide a novel screw depth adjuster that solves the problems mentioned above. 
     SUMMARY OF THE PRESENT INVENTION 
     Therefore it is a primary object of the present invention to provide a screw depth adjuster which not only allows users to learn the depth of the control member/sleeve going to be adjusted in a real-time manner but also avoids damages caused by vibrations generated during the adjustment. 
     It is another object of the present invention to provide a screw depth adjuster which provides fine adjustment of the depth of screws so that the screw can be driven to the position required properly. 
     In order to achieve the above objects, a screw depth adjuster used for allowing users to control the depth of the screw being driven into the workpiece according to the present invention includes a rod assembled with a control member, a driving member and a flared sleeve. The rod consists of a first portion and a second portion formed by extension of the first portion. The first portion is a polygonal rod used for connection with power tools while the second portion is a threaded rod with an assembly portion extended from the rear end. A first plane and a second plane are disposed on two sides of the threaded rod longitudinally and arranged in parallel to each other. The control member consists of a push portion and a polygonal stopper extended from the push portion. Thereby the control member can be pushed and moved slidably axially on the threaded rod. The driving member is provided with an adjustment portion and a sleeve portion extended from the adjustment portion. A polygonal second passage is disposed on the adjustment portion and a threaded third passage is formed by extension of the second passage to the sleeve portion. The shape of the polygonal second passage matches the shape of the polygonal stopper of the control member. The flared sleeve can be pushed by the driving member to be moved on the rod while the control member is used to lock the driving member so that the driving member can&#39;t be rotated and moved on the rod any further. The control member is for positioning the driving member. The driving member used for pushing the flared sleeve can be moved forward/backward on the rod and positioned at the rod for adjustment of the depth of the screw. The flared sleeve is idling once abutting against the surface of the workpiece/material so that the screw will not be driven beyond the depth required in the workpiece. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The structure and the technical means adopted by the present invention to achieve the above and other objects can be best understood by referring to the following detailed description of the preferred embodiments and the accompanying drawings, wherein: 
         FIG. 1  is an explosive view of an embodiment according to the present invention; 
         FIG. 2  is another explosive view of an embodiment viewed from another angle according to the present invention; 
         FIG. 3  is an assembly view of an embodiment according to the present invention; 
         FIG. 4  is a side sectional view of an embodiment according to the present invention; 
         FIG. 5  is a perspective view of an embodiment while in use according to the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Refer to  FIG. 1 ,  FIG. 2  and  FIG. 3 , a screw depth adjuster according to the present invention includes a rod  1 , a control member  3 , a driving member  5 , a first washer  6 , a flared sleeve  10 , a second washer  8  and a fixing member  9 , which are fitted on the rod  1  in turn. The rod  1  consists of a first portion  1   a  and a second portion  1   b  formed by extension of the first portion  1   a . The first portion  1   a  is a polygonal rod  11  used for connection with power tools. The second portion  1   b  is a threaded rod  13  with an assembly portion  15  extended from the rear end of the threaded rod  13 . The assembly portion  15  is provided with a slot  151  and a first C-shaped ring  16  is mounted in the slot  151 . A first plane  14   a  and a second plane  14   b  are disposed on two sides of the threaded rod  13  longitudinally and arranged parallel to each other. A hole  12  is formed on both the first plane  14   a  and the second plane  14   b  at the position close to the first portion  1   a  while a stopping pin  2  is mounted in the hole  12 . 
     The control member  3  is composed of a push portion  31 , a polygonal stopper  32  extended from the push portion  31 , a first passage  33  extended from the push portion  31  to the polygonal stopper  32 , a third plane  34   a  and a fourth plane  34   b . The cross section of the polygonal stopper  32  is a polygon. The third plane  34   a  and the fourth plane  34   b  are arranged in parallel and formed in the first passage  33  at the positions corresponding to the first plane  14   a  and the second plane  14   b  of the threaded rod  13 . Thereby the control member  3  is able to be pushed and moved slidably axially on the threaded rod  13 . The driving member  5  consists of an adjustment portion  51  and a sleeve portion  52  extended from the adjustment portion  51 . A polygonal second passage  511  is disposed on the adjustment portion  51  and a circular limiting groove  512  is arranged at the second passage  511  while a second C-shaped ring  4  is mounted in the circular limiting groove  512 . A third passage  521  is formed by extension of the second passage  511  from the intersection between the second passage  511  and the sleeve portion  52  to the sleeve portion  52 . The third passage  521  is composed of a threaded segment and a smooth segment extended from the threaded segment. A circular groove  522  is formed on the sleeve portion  52 . The shape of the polygonal second passage  511  of the adjustment portion  51  matches the shape of the polygonal stopper  32  of the control member  3 . The cross section of the polygonal second passage  511  is also polygonal, the same as that of the polygonal stopper  32 . 
     A fourth passage  101  is arranged at the flared sleeve  10  and a socket  7  is mounted in the fourth passage  101 . The fourth passage  101  includes a first surface  102  and a second surface  103 . The first washer  6  is abutting against the first surface  102  while the second washer  8  is abutting against the second surface  103 . The flared sleeve  10  is a shade with windows and a contact surface  104  is formed on the bottom of the shade. 
     While being assembled, the sleeve portion  52  of the driving member  5  is first inserted through the first washer  6  and the socket  7 . Then the socket  7  is inserted through the fourth passage  101  of the flared sleeve  10  and mounted into the second washer  8  correspondingly. The first portion  1   a  of the rod  1  is inserted into the third passage  521  and the second portion  1   b  reaches the threaded segment. The second portion  1   b  of the rod  1  is threaded through the threaded segment and continuingly until the assembly portion  15  is driven into the smooth segment of the third passage  521  of the driving member  5  and a part of the assembly portion  15  is exposed outside the sleeve portion  52  of the driving member  5 . Next the fixing member  9  is mounted into the circular groove  522  of the sleeve portion  52 . Then the control member  3  is pushed forward after the third plane  34   a  and the fourth plane  34   b  in the first passage  33  of the control member  3  being aligned with the first plane  14   a  and the second plane  14   b  of the threaded rod  13 . Lastly the stopping pin  2  is inserted into the hole  12 . The assembly process has been completed. 
     As shown in  FIG. 3  and  FIG. 4 , the driving member  5  is mounted into the socket  7  after the socket  7  being mounted into the fourth passage  101  of the flared sleeve  10 . The flared sleeve  10  is able to be rotated on the assembly portion  15 . The flared sleeve  10  can be rotated more smoothly due to the first washer  6  and the second washer  8 . 
     Moreover, the flared sleeve  10  can be pushed by the driving member  5  to be moved on the threaded rod  13 . The polygonal stopper  32  of the control member  3  is used to be mounted into the polygonal second passage  511  of the adjustment portion  51  correspondingly and the second C-shaped ring  4  is used to temporarily hold and position the control member  3  for preventing the control member  3  from being released. At the moment, the driving member  5  is locked by the control member  3  and unable to be rotated and moved on the threaded rod  13 . As to the driving member  5 , it is used to push the flared sleeve  10  so that the flared sleeve  10  is able to be moved and positioned at any position of the threaded rod  13  for adjustment of the depth of the screw. Thereby the flared sleeve  10  can be moved forward or backward on the threaded rod  13  under control of the longitudinal movement of the diving member  5  which is determined according to the depth of the screw required by users. Thereby the screw will not be driven beyond the depth required in the workpiece and dents formed on the surface of the workpiece can be minimized. 
     During the driving operation, a method for driving a screw to a depth required steadily according to the present invention includes the following steps. First rotate the driving member  5  on the threaded rod  13  to move to the positioned required. Now the flared sleeve  10  is pushed by the driving member  5  to move forward or backward on the threaded rod  13  synchronously. Then the control member  3  is pushed and inserted into the second passage  511  of the driving member  5  until the polygonal stopper  32  being mounted into the polygonal second passage  511 . Thereby the driving member  5  is locked by the control member  3 , unable to be moved and rotated. 
     As shown in  FIG. 4 , while in use, first a head of a screwdriver bit  17  is placed into assembly portion  15  of the driving member  5  to be mounted and positioned therein. At the moment, the working end of the screwdriver bit  17  is exposed outside the contact surface  104  of the flared sleeve  10 . When the user rotates the driving member  5 , the flared sleeve  10  is synchronously driven to move longitudinally. The user can directly see the length of the working end of the screwdriver bit  17  protruding from the contact surface  104  of the flared sleeve  10 . After finding the length between the working end of the screwdriver bit  17  and the contact surface  104 , the control member  3  is pushed and inserted into the second passage  511  of the driving member  5  until the polygonal stopper  32  is mounted into the second passage  511  so that the driving member  5  is locked and unable to be rotated and moved. Now the first portion  1   a  of the rod  1  is connected to a power tool while a screw  18  is fitted on the working end of the screwdriver bit  17 . Once the present invention is driven by the power tool to rotate until the contact surface  104  of the flared sleeve  10  is abutting against the surface of the workpiece/material  19 , the flared sleeve  10  is idling and unable to drive the screw  18 , as shown in  FIG. 5 . 
     In summary, the present invention has the following advantages: 
     1. The user can see the length of the working end of the screwdriver bit  17  protruding from the contact surface  104  of the flared sleeve  1  in a real time manner while operating the driving member  5  so that the screw depth can be adjusted all at once. 
     2. The present device provides fine adjustment of the screw depth due to that the shape of the polygonal second passage  511  of the adjustment portion  51  matches the shape of the polygonal stopper  32  of the control member  3 . When the driving member is rotated to a required position which is corresponding to one side of the polygonal cross section of the polygonal stopper  32 . Each side of the polygonal cross section represents a scale of fine adjustment. There are at least four sides of the polygonal cross section. The polygon can be a hexagon, an octagon, a dodecagon, a star polygon or a circle with a zig zag border. Take the octagon as an example. Compared with the device available now, the present invention provides fine adjustment of the screw depth. In the device available now, the device needs to be rotated at least half a circle as one scale for adjustment of the depth. It is assumed that the depth being adjusted is 1 mm when the device available now is rotated a circle. Thus one scale (being rotated half a circle) is 1 mm/2. That&#39;s 0.5 mm. Owing to the octagon of the present invention, one scale is 1 mm/8. In the present invention, the minimum depth able to be adjusted is 1 mm/8. That&#39;s 0.125 mm. Thus the polygonal shape of the present invention provides the fine adjustment function. 
     3. The first passage  33  of the control member  3  are provided with the third plane  34   a  and the fourth plane  34   b  which are arranged parallel to each other and aligned with the first plane  14   a  and the second plane  14   b  of the threaded rod  13  respectively. Thereby the control member  3  is able to be moved slidably on the threaded rod  13 . Owing to the parallel design of the planes  34   a ,  34   b , the impact force acted on the first passage  33  of the control member  3  can be dispersed and the control member  3  will not be deformed. 
     Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details, and representative devices shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalent.