MULTI-AXIS COMPUTER NUMERICAL CONTROL MACHINE TOOL WITH INTEGRALLY-CONTROLLED SAW AND METHOD

Abstract

A CNC machining center that includes a machine base and a machine tool positioned on the base for carrying out a machining operation on a workpiece. A work table is positioned on the base and is adapted for supporting the workpiece and moving the workpiece relative to the machine tool during a machining operation. A saw is positioned above the work table in a longitudinally-offset direction from the machine tool for carrying out a sawing operation on the workpiece. The saw may be a band saw.

Claims

1. A CNC machining center, comprising: a. a machine base; b. a multi-axis machine tool positioned on the base for carrying out a machining operation on a workpiece. c. a work table positioned on the base and adapted for supporting the workpiece as the workpiece moves relative to the machine tool; d. a saw positioned above the work table in a linearly offset position relative to the machine tool for carrying out a sawing operation on the workpiece; and e. a programmable digital computer and computer interface for controlling the operation of the machine tool, work table and saw of the machining center.

2. A CNC machining center according to claim 1, wherein the saw includes a continuous band having saw teeth positioned for sawing rotation on two spaced-part drive and driven band saw wheels.

3. A CNC machining center according to claim 2, wherein the band saw wheels are positioned in respective housings that are positioned outboard of opposing sides of the work table.

4. A CNC machining center according to claim 2, wherein the saw is positioned above the work table in a downstream orientation relative to the machine tool whereby the machine tool is adapted to carry out the machining operation on the workpiece upstream of the sawing operation.

5. A CNC machining center according to claim 4, wherein the work table is mounted on the base for movement on at least one longitudinally-extending trackway relative to the machine tool and the saw.

6. A CNC machining center according to claim 4, wherein the saw is positioned on a laterally-extending gantry mounted on legs that straddle the at least one trackway for moving the saw vertically relative to the work table.

7. A CNC machining center according to claim 4, wherein the saw is longitudinally stationary relative to the work table and the vertical movement relative to the work table is under the control of the computer for permitting the blade to perform horizontal cuts on the workpiece positioned on the work table as it passes under the saw gantry.

8. A CNC machining center according to claim 4, including a tool head gantry supported by a pair of laterally-spaced legs that straddle the work table, a beam section on which is mounted a tool head assembly mounted for lateral movement on a horizontal rail supported by the beam section and mounted for vertical movement on a vertical rail supported by the beam section.

9. A CNC machining center according to claim 1, including an outfeed table positioned linearly downstream of the work table wherein the outfeed table has a length that is twice a length of the work table whereby the machine tool is adapted to reach all points on the workpiece and subsequently, for the saw to fully sever a horizontal portion of the workpiece.

10. A CNC machining center according to claim 9, wherein the work table has a length of about 11 ft. (3.3 m) and the outfeed table having a length of about 23 ft. (7 m).

11. A method of machining a workpiece under the control of a CNC machining center, comprising the steps of providing: a. a machine base; a multi-axis machine tool positioned on the base for carrying out a machining operation on a workpiece; a work table positioned on the base and adapted for supporting the workpiece as the workpiece moves relative to the machine tool; a saw positioned above the work table in a linearly offset position relative to the machine tool for carrying out a sawing operation on the workpiece; and a programmable digital computer and computer interface for controlling the operation of the machine tool, work table and saw of the machining center; b. positioning a workpiece in a stationary condition on the work table; c. moving the workpiece and the machine tool relative to each other to perform a machining step on the workpiece under the control of the computer; d. moving the workpiece and the saw relative to each other to perform a sawing step on the workpiece under the control of the computer to sever a topmost layer of the workpiece from an underlying layer of the workpiece; and e. removing the severed topmost layer of the workpiece from the underlying layer of the workpiece.

12. A method of machining a workpiece according to claim 11, and including the step of maintaining the workpiece stationary on the work table and moving work table relative to the machine tool and saw.

13. A method of machining a workpiece according to claim 11, and including the steps of performing the machining step upstream of the saw, moving the workpiece downstream to the saw, and performing the sawing step subsequently to and downstream from the machining step.

14. A method of machining a workpiece according to claim 11, including the step of providing an outfeed table positioned linearly downstream of the work table for supporting the workpiece during the sawing step.

15. A method of machining a workpiece according to claim 14, wherein the outfeed table has a length that is twice a length of the work table whereby the machine tool is adapted to reach all points on the workpiece and subsequently, for the saw to fully sever a horizontal portion of the workpiece.

16. A method of machining a workpiece according to claim 14, wherein the work table has a length of about 11 ft. (3.3 m) and the outfeed table having a length of about 23 ft. (7 m).

17. A method of machining a workpiece according to claim 11, wherein the workpiece comprises a material having a honeycomb structure.

18. A method of machining a workpiece according to claim 11, wherein the computer is programmed to carry out the steps b, c and d sequentially and without human intervention.

19. A method of machining a workpiece according to claim 11, and including the steps of repetitively moving the workpiece and the saw relative to each other to perform a sawing step on the workpiece under the control of the computer to sever successive topmost layers of the workpiece from an underlying layer of the workpiece, and removing the severed successive topmost layers of the workpiece from the underlying layer of the workpiece.

20. A method of machining a workpiece according to claim 19, wherein the band saw wheels are positioned in respective housings that are positioned vertically above and outboard of opposing sides of the work table, the band saw adapted for making both vertical sawing cuts and horizontal sawing cuts on the workpiece.

21. A method of machining a workpiece under the control of a CNC machining center, comprising the steps of: a. positioning a multi-axis machine tool on a base, the multi-axis machine tool capable of carrying out a machining operation on a workpiece; b. positioning a workpiece in a stationary condition on a work table positioned on the base, the work table supporting the workpiece as the workpiece moves relative to the multi-axis machine tool; c. moving the workpiece and the multi-axis machine tool relative to each other to perform a machining step on the workpiece under the control of a programmable digital computer; d. positioning a saw above the work table in a linearly offset position relative to the machine tool, the saw capable of carrying out a sawing operation on the workpiece; and e. moving the workpiece and the saw relative to each other to perform a sawing step on the workpiece under the control of the programmable digital computer to sever a topmost layer of the workpiece from an underlying layer of the workpiece.

22. The method of machining a workpiece under the control of a CNC machining center according to claim 21, further including the steps of maintaining the workpiece stationary on the work table and moving the work table relative to the machine tool and saw.

23. The method of machining a workpiece under the control of a CNC machining center according to claim 21, further including the steps of performing the machining step upstream of the saw, moving the workpiece downstream to the saw, and performing the sawing step subsequently to and downstream from the machining step.

24. The method of machining a workpiece under the control of a CNC machining center according to claim 21, further including the step of providing an outfeed table positioned linearly downstream of the work table for supporting the workpiece during the sawing step.

25. The method of machining a workpiece under the control of a CNC machining center according to claim 24, wherein the outfeed table has a length that is twice a length of the work table whereby the machine tool is adapted to reach all points on the workpiece and subsequently, for the saw to fully sever a horizontal portion of the workpiece.

26. The method of machining a workpiece under the control of a CNC machining center according to claim 24, wherein the work table has a length of about 11 ft. (3.3 m) and the outfeed table having a length of about 23 ft. (7 m).

27. The method of machining a workpiece under the control of a CNC machining center according to claim 21, wherein the workpiece comprises a material having a honeycomb structure.

28. The method of machining a workpiece under the control of a CNC machining center according to claim 21, wherein the computer is programmed to carry out the steps b, c and d sequentially and without human intervention.

29. The method of machining a workpiece under the control of a CNC machining center according to claim 21, further including the step of repetitively moving the workpiece and the saw relative to each other to perform a sawing step on the workpiece under the control of the computer to sever successive topmost layers of the workpiece from an underlying layer of the workpiece, and removing the severed successive topmost layers of the workpiece from the underlying layer of the workpiece.

30. The method of machining a workpiece under the control of a CNC machining center according to claim 29, wherein the band saw wheels are positioned in respective housings that are positioned vertically above and outboard of opposing sides of the work table, and the band is adapted for making both vertical sawing cuts and horizontal sawing cuts on the workpiece.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The present invention is best understood when the following detailed description of the invention is read with reference to the accompanying drawings, in which:

[0040] FIG. 1 is a top perspective view of a CNC machining center according to one preferred embodiment of the invention;

[0041] FIG. 2 is a front elevation of the machining center of FIG. 1;

[0042] FIG. 3 is a top plan view of the machining center of FIG. 1;

[0043] FIG. 4 is a side elevation of the machining center of FIG. 1; and

[0044] FIG. 5 is a top perspective view of the machining center of FIG. 1 viewed from the output end, with a workpiece in position beneath the machine tool head.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0045] Referring now to FIGS. 1-5 of the drawings, a CNC machining center 10 is shown. The machining center 10 includes a base 12 supporting a work table 14. A pair of laterally-spaced trackways 16 and 18 is mounted on opposing sides of and parallel to a longitudinal axis of the base 12 and form an elongated outfeed table 19. As illustrated, machining center 10 also includes a tool head gantry 20 supported by a pair of laterally-spaced legs 24 and 26 that straddle the work table 14 and the trackways 16, 18.

[0046] The tool head gantry 20 supports a beam section 28 on which is mounted a tool head assembly 30, for example a 3-axis or 5-axis tool head assembly. The tool head assembly 30 moves laterally on a horizontal rail 32 supported by the beam section 28. The tool head assembly 30 is mounted for vertical movement on a vertical rail 34. The work table 14 is mounted on a chain drive 15 that moves the work table 14 longitudinally along the trackways 16, 18 in relation to the tool head assembly 30 to achieve the desired machining steps.

[0047] The machining center 10 includes a laterally-extending band saw gantry 40 mounted on legs 42, 44 that straddle the trackways 16, 18. The band saw gantry 40 mounts a band saw 52 that extends laterally across the machining center 10. The band saw 52 includes drive and driven band saw wheels 53, 55 positioned in protective housings 54, 56, respectively. A top blade guard 58 connects the housings 54, 56 for movement of the blade 60 laterally and horizontally across the width of the machining center 10. The band saw 52 is longitudinally stationary, and its vertical movement permits the blade 60 to perform horizontal cuts on a workpiece as it passes under the band saw gantry 50. Other positions and orientations of the band saw 52 may be alternatively adopted and used.

[0048] As described above and by way of example only, one specific use of the machining center 10 is machining honeycomb materials. As shown in FIG. 1, a workpiece “W” in the form of a large block of honeycomb, for example, 4-5 ft. (1.2-1.5 m) wide, by 8-10 ft. (2.4-3 m long), by 3 ft. to 4 ft. (0.9-1.2 m thick) is placed on the work table 14. A workpiece this large may be held to the work table 14 by its own weight, stabilized by toe clamps or some similar hold down device. The tool head assembly 30 machines the top of the workpiece “W” into the desired shaped part or parts while still integral with the workpiece “W”. The tool head assembly 30 may rout a variety of channels in the workpiece “W”, including tapers, chamfers and undercut areas down into the workpiece “W”.

[0049] Then, the workpiece “W” is moved on the work table 14 downstream to the band saw gantry 40 and the band saw 52 performs a computer-controlled horizontal cut that separates the top machined part from the “parent” workpiece “W.” The workpiece “W” can then be removed and transported to another location for further fabrication. This process step can be repeated, with the work table 14 being moved upstream, the band saw indexed vertically downwardly, and each pass of the workpiece under the band saw 52 removing the top machined part from the “parent” workpiece “W”, the depth of which diminishes with each pass.

[0050] To accomplish this, the outfeed portion of the work table 14 is significantly longer than in known CNC machining centers so that the full extent of the workpiece “W” can pass under the band saw 52. As one example, the overall length of the work table 14 and the outfeed table 19 may be approximately 34 ft. (10 m). To fully accommodate the necessity of the tool head assembly 30 to reach all points on the workpiece “W”, and subsequently, for the band saw 52 to fully sever a horizontal layer of the workpiece “W”, a work table 14 having a length of approximately 11 ft. (3.3 m) and the outfeed table 19 having a length of approximately 23 ft. (7 m) is sufficient to process a block of honeycomb 4-5 ft. (1.2-1.5 m) wide, by 8-10 ft. (2.4-3 m long), by 3 ft. to 4 ft. (0.9-1.2 m thick), as referenced above.

[0051] The machining center is controlled by a programmable digital computer 70 having, for example, a monitor 72 mounted on a portable workstation 74.

[0052] Another use of the machining center 10 includes utilizing a honeycomb material that has been potted to form a structural material. The potting process may be a permanent process that results in a honeycomb structure filled with a cured, hardened material such as an epoxy resin, urethane or other potting material. The potting process may also be a temporary process described above where the potting material is infused into the honeycomb to stabilize and strengthen the honeycomb during machining with the potting material thereafter being extracted from the honeycomb by, for example, heat.

[0053] The machining center 10 is also suitable for machining and sawing workpieces not having a honeycomb structure.

[0054] A CNC machining center that incorporates both a machine tool head and a band saw according to the invention has been described with reference to specific embodiments and examples. Various details of the invention maybe changed without departing from the scope of the invention. Furthermore, the foregoing description of the preferred embodiments of the invention and best mode for practicing the invention are provided for the purpose of illustration only and not for the purpose of limitation, the invention being defined by the claims.