1. Field of the Invention
This invention relates to a fast changeable worktable of a carving machine.
2. Description of the Prior Art
Commonly, a carving machine is used to create characters, pictures, etc. on a workpiece. As shown in
Next, as shown in
1. As a gap always exists between the screw 207 and the threaded hole 210 of the driven base 209, the worktable 202 is to vibrate easily while the carving machine 200 is operating, possible to unexpectedly displace the worktable 202 to downgrade working precision.
2. The worktable 202 is unchangeable because it is fixedly screwed with the bottom base 201. Thus for a workpiece longer than the worktable, the carving machine 200 cannot work for it.
The object of this invention is to offer a fast changeable worktable of a carving machine, without vibrating while working.
The main characteristics of the invention are a bottom base, a main table and a driving unit. The bottom base possesses a sliding groove formed in a top with a pair of sidewalls respectively located at two opposite sides, and a bottom wall connecting the two sidewalls. At least one of the sidewalls is installed with a first pressing portion positioned axially along the sliding groove. And at least one end of the sliding groove is extended to an edge of the bottom base so as to correspondingly form an opening along the edge. The main table is fitted on the sliding groove, provided with a bottom surface, a top surface and two circumferential sides to correspond to the bottom base. A rack is fixed under the bottom surface, positioned axially along the sliding groove. A second pressing portion is located below each of the circumferential sides to mutually squeeze with the first pressing portion tightly. The driving unit is installed between the bottom base and the main table, provided with a driving shaft having a gear engaged with the rack of the main table.
With the gear engaged with the rack to enable the main table to slide on the sliding groove, the main table can be directly dragged out from one of the openings and reloaded with another one from the opening according to the length of a workpiece. And with the first pressing portion tightly squeezing with the second pressing portion, the worktable can work steadily without vibrating, assuring the gear of the driving unit to keep completely engaging with the rack of the main table from slipping, affecting precise position of the main table.
This invention is better understood by referring to the accompanying drawings, wherein:
The bottom base 10 has a sliding groove 11 formed in the top. The sliding groove 11 is provided with a pair of sidewalls 111 respectively located at two opposite sides, a bottom wall 112 connecting the sidewalls 111, and a fixing groove 113 recessed outward from top of the sidewalls 111 respectively. At least one of the sidewalls 111 is installed with a first pressing portion 12 positioned axially along the sliding groove 11. The first pressing portion 12 includes a fixing plate 121 positioned in the fixing groove 113, and a restricting projection 122 extended from the fixing plate 121 toward another sidewall 111. In this embodiment of the invention, the first pressing portion 12 is set on each of the sidewall 111. At least one end of the sliding groove 11 is extended to an edge of the bottom base 10, so as to correspondingly form an opening 114 along the edge. In this embodiment of the invention, two ends of the sliding groove 11 are extended to two corresponding edges of the bottom base 10, with two openings 114 formed.
The main table 20 is fixed on the sliding groove 11, provided with a bottom surface 21, a top surface 22 and two circumferential sides 23 corresponding to the bottom base 10. Fixed under the bottom surface 21 is a rack 24 positioned axially along the sliding groove 11. The main table 20 is further provided with a second pressing portion 25 located below each of the circumferential sides 23 to mutually squeeze with the first pressing portion 12 tightly. In this embodiment of the invention, the second pressing portion 25 is provided with a fixing block 251 employed to be fixed with the circumferential side 23, a wedge-shaped groove 252 recessed in one side of the fixing block 251 to fit the restricting projection 122 of the first pressing portion 12, and a dustproof projection 253 obliquely extended down from an upper edge of the wedge-shaped groove 252.
The driving unit 30 is installed between the bottom base 10 and the main table 20, provided with a driving shaft 31 having a gear 32 engaging with the rack of the main table 20. In this embodiment of the invention, the driving unit 30 is positioned on the bottom wall 112 of the sliding groove 11.
Next, as shown in
It should be noted that with the engagement of the gear 32 and the rack 24, the main table 20 can slide on the sliding groove 11 of the bottom base 10. If a workpiece to be carved is lengthier than the main table 20, the main table 20 can be directly dragged out from one of the openings 114 and replaced with a longer one reloaded on the sliding groove 11 through the opening 114. That is, various main tables 20 can be prepared and swiftly changed to cope with workpieces different in length, with a wide application for the changeable worktable 100.
Furthermore, with the dustproof projection 253 extended out from an edge of the wedge-shaped groove 252 of the second pressing portion 25, wastes cut off a workpiece can be prevented from entering the wedge-shaped groove 252 so as to keep the restricting projection 122 and the wedge-shaped groove 252 from deadlocking with each other or abrasively damaged.
While the preferred embodiment of the invention has been described above, it will be recognized and understood that various modifications may be made therein and the appended claims are intended to cover all such modifications that may fall within the spirit and scope of the invention.