GANTRY TABLE WITH ADJUSTABLE RAILS

A gantry table includes a table main body. A gantry rail extends along the table main body, and a gantry rack extends along the table main body. The gantry table includes a gantry comprising a pinion gear that engages the gantry rack. The pinion gear drives the gantry to move along the table main body on the gantry rail. A tool bracket is movable along the gantry. The gantry table further includes a first adjustment bar and a second adjustment bar. The gantry rail and the gantry rack are attached to both of the first adjustment bar and the second adjustment bar. A joiner plate joins the first adjustment bar to the second adjustment bar. The gantry table includes a vertical adjustment that is configured to adjust a vertical position of the joiner plate with respect to the table main body. The gantry table further includes a depth adjustment configured to adjust a lateral position of the joiner plate with respect to the table main body.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to gantry tables, in particular to CNC plasma cutting tables having a cutting torch mounted on a gantry.

Description of Related Art

It is known to provide a CNC plasma cutting table having a cutting torch mounted to a gantry. The gantry can move along the length of the cutting table on tracks or rails. The torch is held in a movable clamp or bracket that is mounted to the gantry. The movable clamp or bracket moves the torch along the gantry, between lateral sides of the cutting table. Thus, the torch is movable in two perpendicular directions, such as in an X direction along the length of the gantry and in a Y direction along the length of the table as the gantry moves.

BRIEF SUMMARY OF THE INVENTION

The following summary presents a simplified summary in order to provide a basic understanding of some aspects of the devices, systems and/or methods discussed herein. This summary is not an extensive overview of the devices, systems and/or methods discussed herein. It is not intended to identify critical elements or to delineate the scope of such devices, systems and/or methods. Its sole purpose is to present some concepts in a simplified form as a prelude to the more detailed description that is presented later.

In accordance with one aspect of the present invention, provided is a gantry table. The gantry table includes a table main body. A gantry rail extends along the table main body, and a gantry rack extends along the table main body. The gantry table includes a gantry comprising a pinion gear that engages the gantry rack. The pinion gear drives the gantry to move along the table main body on the gantry rail. A tool bracket is movable along the gantry. The gantry table further includes a first adjustment bar and a second adjustment bar. The gantry rail and the gantry rack are attached to both of the first adjustment bar and the second adjustment bar. A joiner plate joins the first adjustment bar to the second adjustment bar. The gantry table includes a vertical adjustment that is configured to adjust a vertical position of the joiner plate with respect to the table main body. The gantry table further includes a depth adjustment configured to adjust a lateral position of the joiner plate with respect to the table main body.

In accordance with another aspect of the present invention, provided is a gantry table. The gantry table includes a table main body. A gantry rail extends along the table main body, and a gantry rack extends along the table main body. The gantry table includes a gantry comprising a pinion gear that engages the gantry rack. The pinion gear drives the gantry to move along the table main body on the gantry rail. A tool bracket is movable along the gantry. The gantry table includes a plurality of adjustment bars. The plurality of adjustment bars adjustably attach the gantry rail and the gantry rack to the table main body. The gantry table further includes a plurality of depth adjustments configured to adjust lateral positions of the plurality of adjustment bars with respect to the table main body. The gantry table includes a plurality of vertical adjustments configured to adjust vertical positions of the plurality of adjustment bars with respect to the table main body.

In accordance with another aspect of the present invention, provided is a plasma cutting table. The plasma cutting table includes a table main body. A gantry rail extends along the table main body, and a gantry rack extends along the table main body. The plasma cutting table includes a gantry comprising a pinion gear that engages the gantry rack. The pinion gear drives the gantry to move along the table main body on the gantry rail. A plasma torch bracket is movable along the gantry. The plasma cutting table further includes a first adjustment bar and a second adjustment bar. The gantry rail and the gantry rack are attached to both of the first adjustment bar and the second adjustment bar. A joiner plate joins the first adjustment bar to the second adjustment bar. The plasma cutting table includes a jacking plate. A first screw adjustment extends between the jacking plate and the joiner plate and is configured for adjusting a vertical position of the joiner plate with respect to the jacking plate. A second screw adjustment is configured for adjusting a lateral position of the joiner plate with respect to the table main body.

DETAILED DESCRIPTION OF THE INVENTION

Embodiments of the present invention relate to gantry tables or CNC (computer numeric control) tables, such as CNC plasma cutting tables. The present invention will now be described with reference to the drawings, wherein like reference numerals are used to refer to like elements throughout. It is to be appreciated that the various drawings are not necessarily drawn to scale from one figure to another nor inside a given figure, and in particular that the size of the components are arbitrarily drawn for facilitating the understanding of the drawings. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It may be evident, however, that the present invention can be practiced without these specific details. Additionally, other embodiments of the invention are possible and the invention is capable of being practiced and carried out in ways other than as described. The terminology and phraseology used in describing the invention is employed for the purpose of promoting an understanding of the invention and should not be taken as limiting.

FIG. 1shows an example gantry table. The gantry table inFIG. 1is a plasma cutting table10and the invention will be discussed in the context of a plasma cutting table. However, aspects of the invention are applicable to other types of gantry tables for performing CNC operations on a workpiece, and the invention need not be limited to plasma cutting tables.

The plasma cutting table10has a main body12upon which a workpiece, such as a metal sheet or plate, is placed. A plasma cutting torch (not shown) is attached to a movable tool bracket14or plasma torch bracket, that can move back and forth along a gantry16(e.g., in an X direction). The gantry16can move back and forth along the length of the cutting table's main body12on tracks or rails (e.g., in a Y direction). The plasma cutting table10can be programmed to make precise cuts in the workpiece through controlled movements of the bracket14and gantry16in the X and Y directions, respectively. In certain embodiments, the tool bracket14can move the tool vertically toward and away from the workpiece in a Z direction, so that the tool can be moved in three perpendicular directions.

The plasma cutting table10can include an upper water chamber located adjacent the workpiece, and a lower water chamber located beneath the upper water chamber. During a plasma cutting operation, the upper water chamber is filled with water. The water can be drained into the lower water chamber to allow the upper water chamber to be cleaned. Compressed air can be used to pressurize the lower water chamber and return the water to the upper water chamber. The plasma cutting table10can be connected to a source of compressed air and can include valves, such as solenoid valves, for controlling the draining of the upper water chamber and emptying of the lower water chamber. Operation of the valves can be controlled by a control system, and can be operated automatically or manually through a human-machine interface (HMI)18of the plasma cutting table10.

The gantry16is mounted to a respective foot portion20located on either side of the gantry. The foot portions20move along gantry rails that are mounted to the main body12of the cutting table10. As best shown inFIG. 3, the foot portion20of the gantry16includes a pinion gear22that engages a rack24gear, which extends along the table main body. Example pinion gears22include helical and spur gears. A gantry rail26also extends along the table main body, generally parallel with the rack24. The rail26can be separate from the rack24or attached to the rack. The foot portion20of the gantry16rides along the rail, such as on wheels, bearings, etc. A motor (not shown) or driven pulley or gear can be located within the foot portion20and coupled to the pinion gear22. The motor, pulley, gear, etc. drives the pinion gear22to move the foot portion20along the rack24and rail26, to thereby position the gantry16in the Y direction along the length of the cutting table10. Both lateral sides of the cutting table10can have a similar rack, pinion and rail system for moving the gantry16along the table.

With reference toFIG. 2, the drive system for the gantry16can include a belt28that is similar to an endless belt but is attached to the front and rear sides of the foot portion20of the gantry. The belt28passes over rollers30located at both ends of the cutting table10and wraps around the drive system for the gantry16. The cutting table10can include belt guides32to correctly position the belt28. The belt28can be any suitable flexible material, such as a metallic band, a rubber belt, and the like. The belt28serves to protect the rack and pinion gear from direct spray during a cutting operation and from accumulating debris. The belt28also serves as a barrier to access of the rack and pinion during operation of the cutting table10. The belt28can be seen inFIGS. 1 and 2, but is removed inFIGS. 3-7. In an alternative embodiment, the belt28and rollers30can be replaced with a solid guard that does not move with the gantry. For example, the rack24could be located beneath the rail26, and the foot portion20of the gantry16can be located substantially lateral of or beyond the rack and rail system (e.g., with the pinion22and bearings projecting inward to engage the rack and rail). In such an embodiment, the solid guard can extend laterally over the rack24and rail26, and the foot portion20can move back and forth along the cutting table10and solid guard, just outside of the guard.

For optimal mechanical performance of the gantry16, the racks24and rails26for the gantry foot portions20on either side of the cutting table10should be correctly aligned parallel with each other and with respect to the length of the cutting table. The cutting table10includes an adjustment system for adjusting the vertical position of the racks and rails, and their lateral offset from the main body of the cutting table, at various adjustment points along the table. The adjustment system will be discussed with reference toFIGS. 4-10.

The racks24and rails26are attached to a series of adjustment bars34and joiner plates36. The joiner plates36are located between the adjustment bars34and at the terminal ends of the adjustment bars and serve to attach the adjustment bars34to the main body12of the cutting table10. Moreover, the joiner plates36allow adjustment of the position of the adjustment bars34with respect to the main body12of the cutting table. By adjusting the position of the joiner plates36(e.g., up and down and in and out with respect to the cutting table main body), the final position of the adjustment bars34and the attached rack and rail system can be adjusted and properly aligned. Alternatively, the adjustment bars34can be attached directly to the main body12of the cutting table10without joiner plates36, and vertical and lateral adjustments to the position of the adjustment bars can be made on the adjustment bars themselves rather than to the joiner plates as described in below.

Each lateral side of the cutting table10can include a suitable number of adjustments bars34as desired, such as two, three, four, five, six, more than six, etc. In the example embodiment shown in the figures, the cutting table10includes four adjustment bars34on each lateral side of the table, and five joiner plates36(three joiner plates located between adjustment bars and two joiner plates located at the terminal ends of the adjustment bars). The racks24and rails26are longer than the adjustment bars34and are attached to multiple adjustment bars. In certain embodiments, the cutting table10has a single rack24and single rail26on each lateral side of the table, and the single rack24and rail26are attached to each of the adjustment bars34on that side, and to the joiner plates if present.

In certain embodiments, the main body12of the cutting table10includes a series of leveling pads38to which the joiner plates36are attached. The position of the leveling pads38with respect to the main body12of the cutting table can be fixed (i.e., not adjustable). The leveling pads38can be attached to the main body12in any suitable fashion, such as by welding or via the use of appropriate fasteners (e.g., bolting, screwing, etc.) Each leveling pad38is aligned with a joiner plate36and is located between the table main body12and a corresponding joiner plate.

The cutting table10includes a plurality of depth adjustments42for adjusting the lateral positions of the adjustment bars34(and, thus, the attached rack24and rail26) with respect to the table main body12. In the embodiments shown in the figures, the joiner plates36include the depth adjustments42, which set the lateral positions of the joiner plates, such as their offset from the leveling pads38. The depth adjustments42can be screw adjustments (e.g., set screws) that can be threaded into the joiner plates36to contact the leveling pads38and push the joiner plates outward from the leveling pads38. Thus, the joiner plates36can be moved inward and outward with respect to the leveling pads38and the main body12of the cutting table10via the depth adjustments42. The depth adjustments42could take any form suitable for moving the joiner plates36toward and away from the leveling pads38, such as a small ball screw, an adjustable wedge or shim, and the like.

The cutting table10further includes a plurality of vertical adjustments for adjusting the vertical positions of the adjustments bars34(and, thus, the attached rack24and rail26) with respect to the table main body12. In the embodiments shown inFIGS. 4-8, jacking plates40are attached to the leveling pads38and are used to adjust the vertical position of the joiner plates36and their attached adjustment bars34. The jacking plates40include one or more vertical actuators44that raise and lower the joiner plates36along the leveling pads38. The vertical actuators44can extend from and retract toward the jacking plates40to adjust the vertical positions of the joiner plates36with respect to the jacking plates. The vertical actuators44can be in the form of screw adjustment, such as set screws, cap screws, and the like, upon which the joiner plate36sits. Similar to the depth adjustments42, the vertical actuators44could take any form suitable for moving the joiner plates36upward and downward with respect to the leveling pads38. The vertical actuators44extend between the jacking plates40and the joiner plates36and can pass through the jacking plates as shown. For example, the vertical actuator44can pass through a threaded hole in the jacking plate36.

After the joiner plate36is properly positioned by adjusting the depth and vertical adjustments, the position of the joiner plate36on the leveling pad38is fixed by screwing or bolting the joiner plate to the leveling pad. Cap screws46are shown in the example embodiments for securing the joiner plate36to the leveling pad38. Through holes in the joiner plate36for the cap screws46can be slightly oversized to provide some “play”, to accommodate positioning of the joiner plate36on the leveling pad38.

The adjustment bars34, and the rack and rail system for the gantry, would typically be connected to the joiner plates36during adjustment of the joiner plates. As best seen inFIG. 8, the adjustment bars34and joiner plates36can include threaded holes48for attaching the rack and rail system to the adjustment bars and joiner plates. The rack and rail system is not shown inFIG. 8. The rack24and rail26system mounted to the adjustment bars34and joiner plates36can be seen inFIG. 5. The vertical and lateral positions of the adjustment bars34can be adjusted to ensure that the racks24and rails26are substantially straight and parallel to the table main body12and to each other.

An alternative vertical adjustment to the jacking plate and screw system discussed above is shown inFIGS. 9 and 10.FIGS. 9 and 10show an eccentric bushing60that can be rotated to lift/lower the joiner plates36and/or the adjustment bars34. The eccentric bushing60has a head62, a through hole64, and a cam portion66. The through hole64is offset from a central axis68of the cam portion. A screw, such as the cap screw46discussed above for securing the joiner plate, passes through the through hole64. When the eccentric bushing60is rotated via the head62, the cam portion66lifts or lowers the joiner plates36and/or the adjustment bars34. The screw passing through the through hole64(e.g., cap screw46) can then be tightened to fix the position of the eccentric bushing60.

Returning toFIG. 8, the adjustment bars34can be attached to the joiner plates36in any suitable manner. In the example embodiment shown in the figures, the adjustment bars34are thicker than the joiner plates36and are formed to have L-shaped ends that overlap the joiner plates. The adjustment bars34are attached to the joiner plates36through the overlapping portions of the adjustment bars. The adjustment bars34can be screwed to the joiner plates36through the overlapping portions, for example. The joiner plates36can further include dowel pins50for positioning the adjustment bars34on the joiner plates. Alternatively or additionally, dowel pins50can be located on the table main body12for positioning the adjustment bars34along the table main body. The screws52that attach the adjustment bars34to the joiner plate36can be left loose while the position of the joiner plate is adjusted. After the joiner plate36is properly positioned by adjusting the depth42and vertical40,44adjustments, the screws52that attach the adjustment bars34to the joiner plate can be tightened.