Patent Application
20070149099
The present invention relates to a locking screw nut, and more particularly to a locking screw that can be secured or removed quickly without using a tool.
A vast majority of assembled electric tools, particularly the rotary grinding tools can be replaced by general pneumatic tools, which feature the power-saving and easy-to-operate advantages, and thus become popular and used extensively. The common pneumatic tools include pneumatic grinding tools and pneumatic polishing tools, and the theory of pneumatics for these pneumatic tools uses a compressed air as the motive force to convert the energy stored in the compressed air into the mechanical energy for the manufacture, wherein a pneumatic motor installed in the pneumatic grinding tool to drive an axle of the pneumatic grinding tool to rotate, so as to drive the grinding object installed at the end of the axle to rotate and achieve the manufacture with a grinding and polishing effect. After the grinding and polishing made by the grinding tool, any flaw or rust on the work piece can be removed to produce a flat and bright surface.
Referring to
However, if it is necessary to replace a worn-out grinding object 302 from the pneumatic grinding tool 30, then a removing tool (such as a wrench) must be used to secure/loosen the screw nut 301, and a general user usually needs to use two or more wrenches for the removal, wherein a wrench 31 is mounted onto the pneumatic grinding tool 30 as a support point, and another wrench 32 is placed on the screw nut 301 and rotate with respect to the screw nut 301 as a force applying point, so at to remove the screw nut 301 and achieve the effect of replacing the grinding object 302. From the measure taken above, it is obvious that the assembling and removing procedures are complicated and laborious.
On the other hand, the wrenches 31, 32 are used only when it is necessary to install/remove the grinding object 302 onto/from the pneumatic grinding tool 30, and the wrenches 31, 32 are not integrally installed to the pneumatic grinding tool 30, and thus the wrenches 31, 32 may be placed anywhere or the wrenches 31, 32 may even be missing easily. If a user needs to replace a grinding object 302 immediately, the user may not be able to find the wrenches 31, 32.
The primary objective of the present invention is to overcome the foregoing shortcomings and avoid the existing deficiencies by providing a tool-less quick locking screw nut to be secured onto a connecting object (such as a pneumatic grinding tool) having a screw thread to substitute the foregoing wrench, wherein the quick locking screw nut includes a base having a circular through hole, a circular plate disposed between the rim of the base and the through hole, and the circular plate includes a plurality of grooves, and the base includes a spacer attached onto a surface of the circular plate and having an external radius smaller than the external radius of the circular plate. Further, the spacer at another surface of the base includes a clamping plate, and the clamping plate includes a group of corresponding grooves, a screw head having an axle portion extended from the screw head and coupled to the connecting object, and the axle portion includes a passage with a female thread, and the axle portion uses another spacer to press a pull-ring tab installed in the groove, and the screw head uses the axle portion to pass through and is riveted to the clamping plate and the base. It is worth to point out that the pull-ring tab can turn the quick locking screw nut into or out from the connecting object without using any removing tool (such as a wrench 32). By turning the pull-ring tab, another connecting object (such as a grinding obeject) can be secured to or removed from the connecting object to achieve the purpose of replacing the grinding object.
On the other hand, the installed quick locking screw nut and the axial protrusion of the pull-ring tab are accommodated in the groove to press onto the circular plate of the base and limited vertically by the two spacers. In such design, the pulling-ring tab and the clamping plate can be securely attached when the connecting object (such as a pneumatic grinding tool) is turned on, so as to prevent the connecting object (such as a grinding object) from being shaken by the high-speed rotations that adversely affects the grinding job.
The technical contents of a tool-less locking screw nut used for locking a threaded connecting object in accordance with the present invention will now be described in more detail hereinafter with reference to the accompanying drawings as follows:
Referring to
Referring to
It is worth to point out that the axial protrusion 231 of the pull-ring tab 23 is accommodated in the groove 241 and presses the circular plate 27 of the base 26, after the quick locking screw nut 2 is installed. Further, the two corresponding spacers 22, 25 are used to limit the pull-ring tab 23 onto the clamping plate 24, so that when the pneumatic grinding tool 1 uses the pneumatic motor (not shown in the figure) for providing a motive force to drive the grinding object 11 to rotate, the pull-ring tab 23 is at a status parallel to the clamping plate 24, and the axial protrusion 231 of the pull-ring tab 23 is limited vertically on the spacer 22, 25, such that the pull-ring tab 23 and the clamping plate 24 are attached securely to prevent the grinding object 11 from being shaken by high-speed rotations.
Referring to
In summation of the description above, the movements of the pull-ring tab 23 leverage a resilient property of the groove 271 to provide a shock absorbing effect when the axial protrusion 231 is limited by the circular plate 27, so as to prevent the axial protrusion 231 from being deformed.
While the invention has been described by way of example and in terms of a preferred embodiment, it is to be understood that the invention is not limited thereto. To the contrary, it is intended to cover various modifications and similar arrangements and procedures, and the scope of the appended claims therefore should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements and procedures.
