Patent Application
20110287699
1. Field of the Invention
The present invention relates to an auto-scraping apparatus for a work piece, and more particularly to an auto-scraping apparatus that can be assembled to a Computerized Numerical Control (CNC) machine tool easily and can rotate to scrape a surface of the work piece accurately.
2. Description of the Prior Arts
In general, a conventional hard rail for a machine tool needs to be scraped before assembly, a scraping process is used to scrape a contacting surface of the conventional hard rail to form multiple recesses in the contacting surfaces of the conventional hard rail. The recesses can contain lubricant to lubricate movement of a moving element on the hard rail, since surface roughness may affect mobility of the moving element on the conventional hard rail.
There are two conventional methods to scrape a work piece: manual scraping method and semi-automatic manual scraping method. In the conventional manual scraping method, a relieving tool is used to scrape recesses into a surface of a work piece. In the semi-automatic manual scraping method, a semi-automatic scraping machine used to scrape recesses into a surface of a work piece.
However, the conventional scraping methods are operated manually to scrape recesses in the work piece, scraping quality is dependent on worker experience and is subject to human error. In addition, the conventional methods are difficult to learn and are time-consuming. Furthermore, the conventional semi-automatic scraping machine is heavy and is not easy to operate.
To overcome the shortcomings, the present invention provides an auto-scraping apparatus for a work piece to mitigate or obviate the aforementioned problems.
The main objective of the present invention is to provide an auto-scraping apparatus for a work piece of a hard rail, and more particularly to auto-scraping apparatus that can be assembled to a CNC machine tool easily and can rotate to scrape a surface of the work piece accurately.
The auto-scraping apparatus for a work piece of a hard rail in accordance with the present invention has a driving device, a linking device and a tool device. The driving device has a connecting frame, a driving motor and a cam. The driving motor is mounted in the connecting frame. The cam is mounted on a bottom of the connecting frame and has an abutting face. The linking device is connected to the driving device and has a main frame, an upper connecting arm, a lower connecting arm, a linking arm and a rotating wheel. The main frame is connected to the driving motor. The connecting arms are pivotally connected to the main frame and the linking arm. The rotating wheel is rotatably mounted on the upper connecting arm and abuts the abutting face of the cam. The tool device is detachably connected to the linking device and has a tool carrier and a relieving tool.
Other objectives, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.
With reference to
With reference to
The connecting frame (11) is connected to the spindle (51) of the CNC machine tool (50) and has a top, a bottom and a connecting rod (111). The connecting rod (111) is mounted on and protrudes from the top of the connecting frame (11) and is connected to the spindle (51) of the CNC machine tool (50).
The driving motor (12) is securely mounted in the connecting frame (11) and has a bottom and a driving shaft (121). The driving shaft (121) is rotatably connected to the bottom of the driving motor (12), extends out of the bottom of the connecting frame (11) and has a free end.
The cam (13) may be semicircular, is securely mounted on the bottom of the connecting frame (11) beside the driving shaft (121) of the driving motor (12) and has a top side, a bottom side, a thickness, a middle, two ends and an abutting face (131). The top side of the cam (13) is securely mounted on the bottom of the connecting frame (11). The abutting face (131) is wavy and is formed on the bottom side of the cam (13). The thickness of the cam (13) at the middle is wider than the thickness of the cam (13) at the ends.
The linking device (20) is securely connected to the driving device (10) and has a main frame (21), an upper connecting arm (22), a lower connecting arm (23), a linking arm (24) and a rotating wheel (25).
The main frame (21) may be U-shaped, is securely connected to the driving motor (12) and has a top side and a bottom side. The top side of the main frame (21) is securely mounted around the free end of the driving shaft (121) of the driving motor (12).
The upper connecting arm (22) is pivotally connected to the main frame (21) near the top side and has a connecting end opposite to the main frame (21) and a top side.
The lower connecting arm (23) is pivotally connected to the main frame (21) near the bottom side under the upper connecting arm (22) and has a connecting end opposite to the main frame (21) and a bottom side. The linking arm (24) is pivotally connected to the connecting ends of the connecting arms (22, 23) to form a four-bar-mechanism with the main frame (21) and the connecting arms (22,23).
The rotating wheel (25) is rotatably mounted on the top side of the upper connecting arm (22) near the connecting end, abuts the abutting face (131) of the cam (13) and has two holding mounts (251). The holding mounts (251) are securely mounted on the top side of the upper connecting arm (22) to hold the rotating wheel (25) on the upper connecting arm (22).
The tool device (30) is detachably connected to the linking device (20) and has a tool carrier (31) and a relieving tool (32). The tool carrier (31) is securely mounted on the bottom side of the lower connecting arm (23) by fasteners and has a mounting surface (311) opposite to the lower connecting arm (23). The relieving tool (32) is securely mounted on the mounting surface (311) of the tool carrier (31).
When the auto-scraping apparatus in accordance with the present invention is used to scrape recesses in a work piece, the driving motor (12) is electrically connected to a computer. The computer comprises a shaft controlling card and a controlling program formed by a software of Laboratory Virtual Instrumentation Engineering Workbench (Lab-View). Then, the computer can control the rotation of the driving shaft (121) of the driving motor (12). With further reference to
After adjusting the location of the linking device (20), the driving motor (12) is actuated by the computer, the linking device (20) is rotated relative to the connecting frame (11) by the driving shaft (121). With reference to
The driving shaft (121) is rotated in a circular motion route relative to the connecting frame (11) by the driving motor (12) and the circular motion route can be delineated into two semicircular motion routes, respectively a front semicircular motion route and a rear semicircular motion route. In the front semicircular motion route of the driving shaft (121), the rotating wheel (25) moves and abuts the abutting face (131) of the cam (13) and the driving shaft (121) is rotated at a fixed rotating speed to allow the relieving tool (32) scraping the surface of the work piece (40). In the rear semicircular motion route of the driving shaft (121), the rotating wheel (25) moves away from the abutting face (131) of the cam (13) and the driving shaft (121) is rotated back to the original position and the rotating speed of the driving shaft (121) is decelerated to zero. Furthermore, during the rear semicircular motion route of the driving shaft (121), the auto-scraping apparatus moves relative to the work piece (40) by the three dimension moving device of the CNC machine tool (50) to form a new recess (41) on the work piece (40) in a next circular motion route of the driving shaft (121). Repeating the aforementioned scraping process, multiple recesses (41) can be quickly and accurately formed in the surface of the work piece (41) by the motion of the auto-scraping apparatus.
The whole weight of the auto-scraping apparatus in accordance with the present invention is only 3.5 kilogram and can be easily assembled to a CNC machine tool (50) by the connecting rod (111) connected to a spindle (51) of the CNC machine tool (50). The rotating speed of the driving shaft (121) can be adjusted by the computer to control the scraping motion of the relieving tool (32) of the tool device (30) to form recesses (41) in a surface of a work piece (40). The depth of each recess (41) in the surface of the work piece (40) can be adjusted to 10 to 20 nano-meters.
Even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and features of the invention, the disclosure is illustrative only. Changes may be made in the details, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.
