Tool to remove damaged bolt heads

A tool to remove square head drain plugs of the type found in diesel semi-truck rear differentials. The tool consists of two circular portions that are joined together. The first circular portion having a void to insert a square head drain plug and the second circular portion having a void to insert a ½ inch ratchet drive. The tool is used by first inserting the square head drain plug into the first circular portion and, if needed, a hammer may be used to force the tool onto the square head drain plug. Then a ratchet wrench is inserted into the void in the second circular portion so that the ratchet wrench may be utilized to rotate the tool. The tool is made from high strength metal so as to overcome resistance presented by rounded edges that may be exist on drain plugs.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to fastener extraction devices and, more particularly, to fastener impact devices for extracting a fastener containing rounded corners on its head from a workpiece by (i) positioning the device on top of the fastener's head, (ii) striking the device with a hammer to cut into the fastener's head in order to remove rounded corners, and (iii) simplifying the removal of the fastener increasing the rotational torquing force that may be applied to the fastener.

2. Description of the Related Art

Removing fasteners from a workpiece after the fastener's head has been rounded is difficult and a number of solutions have been proposed. Some solutions, such as U.S. Pat. No. 6,877,401 to Jon Giltner and U.S. Pat. No. 8,607,670 to Rafal Stawarski, discloses a tool to cut into the fastener with a reverse threading action so as to grip the fastener's head thus destroying the fastener's head in the process. Other solutions, such as U.S. Pat. No. 8,955,415 to Fu-Hua Lin, propose first to make a hole into the head of the fastener and then to insert a tool that will grip the fastener the further it is threaded into the hole and then remove the fastener.

Known systems employ a method that results in the destruction of the fastener and use methods that are time consuming. It would be beneficial to mechanics to have a tool that does not destroy the fastener in the process of removing the fastener and that would not be time consuming in its use.

BRIEF SUMMARY OF THE INVENTION

The preferred embodiment of the tool of the present invention is a socket in the shape of the number “8” rather than being cylindrical in shape as most other sockets are. The void in the upper portion of the tool is sized so as to fit closely over square oil drain plugs commoningly found on diesel semi-trucks. The void in the lower portion of the tool is sized so as to fit onto standard ratchet wrenches. At times the oil drain plug head may have had its edges “rounded” when being inserted or removed by sockets that are not dimensioned to tightly fit of the head of the oil drain plug thus making subsequent insertions and removals of the oil drain plug more difficult. The tool itself may be made from any metal alloy that is harder than the metal alloy used to make oil drain plugs and the edges of the void in the upper portion of the tool are sharpened so as to restore the oil drain plug head back to its normal square shape if the oil drain plug head has rounded edges.

To use the tool one would first place the void found in the upper portion of the tool over the oil drain plug head so that the head may pass into the void. If the plug's head refuses to pass into the void because either the plug's head is slightly oversized or it's edges are rounded, a hammer may be used to force the tool upon the head of the plug by striking the tool when the tool is positioned over the plug's head. When the tool is being forced upon the plug's head, the sharpened edges of the void cut through any excess or deformed metal thus reshaping the head of the plug back to its original square shape. Once the plug's head has passed into the void found in the upper portion of the tool, the drive of a ratchet wrench or similar tool is then inserted into the void found in the lower portion of the tool. The user may apply a torquing force to the ratchet wrench which in turn applies torque to the tool for the insertion or removal of the oil drain plug.

A secondary embodiment of the tool of the present invention contains the upper void of the preferred embodiment containing the sharpened edges but replaces the lower void with a handle so that the use of a ratchet wrench or other similar tool will not be required.

Yet another embodiment of the tool of the present invention reconfigures the tool to be cylindrical in shape with a first opening matching the characteristics of the void in the upper portion of the preferred embodiment and a second opening matching the characteristics of the void in the lower portion of the preferred embodiment.

Yet another embodiment of the tool of the present invention maintains the same configuration of the number “8” as the preferred embodiment but replaces the square void in the upper portion with a void to accommodate oil drain plugs with a hexagonal head.

Neither this summary nor the following detailed description defines or limits the invention. The invention is defined by the claims.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1shows an isometric view of the preferred embodiment of the tool10of the present invention. Tool10is approximately rectangular in shape with an indentation at its mid section to facilitate grasping such that versions of tool10that are shorter in length appear as the number “8”. Tool10may be of any reasonable length and indeed the greater the length that greater amount of torque may be applied when engaging the oil drain plug (“plug”). One half of the tool, drive portion12, contains drive socket16and is used to engage with ratchet wrench22as shown inFIGS. 2 and 3. The opposing half, head portion14, contains head socket18and is used to engage with plug20as shown inFIGS. 2 and 3. Frame11of tool10is to be fabricated of a metal that is much harder than metals used for fabrication of the plugs and must not break apart when being force upon the plugs by a hammer. The opening of drive socket18is dimensioned to be only slightly larger than the dimensions of the plug's head of the plug that is to be removed and the edges of drive socket18are sharpened so as to facilitate the removal of any material present on the surface of the plug's head. The material referred to here may be excess material present as a result of a manufacturing process or from rounding the edges of the plug's head during failed attempts at removing the plug.

Tool10may be used to insert plugs but its primary purpose is to remove plugs whose heads have been rounded due to previous failed attempts at removing the plug. The sharpened edges of head socket18cut away excess material from the plug's head that prevents other tools from securely gripping the head. To use tool10a user will first position head socket18over a plug's head and attempt to fit head socket18onto the plug's head. As the dimensions of head socket18are only slightly larger than the dimensions of the plug's head, any excess material present on the plug's head will prevent head socket18from fitting about the plug's head. By striking tool10with a hammer, excess material present on the plug's head will be removed by the sharpened edges of head socket18allowing tool10to be fitted about the plug's head. Once head socket18is about the plug's head a ratchet wrench may then engage drive socket16and the user may turn the plug by operation of the ratchet wrench.

FIG. 2shows tool10in relationship to ratchet wrench22and plug20. Head socket18of tool10engages the head of plug20. Drive socket16of tool10engages ratchet wrench22. The distance between head socket18and drive socket16adds to the torquing force present in ratchet wrench22. The longer the distance between head socket18and drive socket16the greater the torquing force.

FIG. 3shows tool10in use to remove plug20from rear differential24. InFIG. 3tool10head socket18has been fitted about the head of plug20and ratchet wrench22has engaged tool10drive socket16which is not visible. User26operates on ratchet wrench22which in turn operates on tool10which in turn operates to remove plug20.

FIG. 4shows secondary embodiment of the present invention, tool28. Tool28differs from the preferred embodiment, tool10, in that drive portion12is replaced by handle30. Head portion14containing head socket18remains the same as in tool10. The method of use for tool28is the same as for tool10except that ratchet wrench is not used and user26operates on tool28directly by use of handle30.

FIG. 5shows another secondary embodiment of the present invention, tool32. Tool32differs from the preferred embodiment, tool10, in that tool32is cylindrical as contrasted with tool10which is more rectangular. At one end of tool32is head socket18while at the opposing end is drive socket16which is not visible. Tool32is used in a manner similar to tool10. Tool32is first positioned over the plug's head and if needed is struck by a hammer so that tool32is fitted about the plug's head. Then the user engages ratchet wrench into tool32and operates the ratchet wrench to apply a torquing force on tool32to remove the plug. As both drive socket16and head socket18are along the same axis, tool32does not add to the torquing effect when engaged with ratchet wrench22.

FIG. 6shows another secondary embodiment of the present invention, tool34. Tool34differs from the preferred embodiment, tool10, in that tool34has head socket18that has been configured for use on plugs that have heads that are hexagonal in shape rather than square.