WO2002026440A1

WO2002026440A1 - Multiple spindle multiple carriage spindle positioning system

Info

Publication number: WO2002026440A1
Application number: PCT/US2001/042322
Authority: WO
Inventors: Henry Ramirez Martinez; Hendley W. Hall
Original assignee: Excellon Automation Co.
Priority date: 2000-09-27
Filing date: 2001-09-26
Publication date: 2002-04-04
Also published as: TW520310B

Abstract

In a dual carriage system mounted on a machine tool (1) the carriages (2, 3) are slideably mounted on a gantry (7) mounted to the machine tool for motion along the longitudinal axis of the gantry (7). The machine tool includes a plurality of worktables (5) each positioned at a workstation upon which individual work pieces or stacks of work pieces may be mounted for drilling or other work. The carriages (2, 3) are disposed such that at least a portion of each of the carriages may be moved into a position over the each of the workstations. A plurality of spindles (6, 8) for receiving tools are mounted in a fixed position on each carriage. The spindles are disposed on the carriages such that at least one spindle of each carriage may be positioned over each workstation for drilling.

Description

MULTIPLE SPINDLE MULTIPLE CARRIAGE SPINDLE POSITIONING SYSTEM

Background of the Invention Field of the Invention

The field of this invention relates generally to spindles mounted on carriages and the positioning of such carriages over work pieces to perform work. More specifically the field of this invention relates to multiple carriages each having multiple fixed position spindles, which are moveable to move a set of spindles. Description of the Related Art

The related art is replete with carriages on which spindles are moveably mounted or which move spindles into position over a selected work piece.

Typical of this art is U.S. Patent 2,393,696 to Kraut, et al., for a MACHINE TOOL. The Kraut system shows multiple spindles each of which is mounted on a separate carriage and driven by lead screw drive systems to position the spindles of each carriage over a single work station. Each of the spindles is independently moveable but the system can address only a single work station. Similar to the Kraut patent is U.S. patent 5,882,286 to Aufiero, which shows virtually the identical system having only two spindles each mounted on a single carriage as in Kraut. Lead screw drive systems position the carriages carrying the two spindles over a single work station. The spindles are disposed at the end of the carriages disposed toward the middle of the of the machine tool to permit the two spindles to be positioned as close as possible. This is identical to Kraut except that Kraut provides an area over overlap and Augiero does not permit movement of the carriages to position the spindles much beyond the center. In both Kraut and Augiero, only one work station can be addressed as the carriages cannot move beyond one another.

U.S. patent 5,920,973 to Kosmowski shows a plurality of spindles each mounted on a slide which are ganged together to form a set of spindles which are driven by spindle drive system to position the spindles over a number of work stations. This spindles may be individually driveable or are ganged together to be driven as a ganged set. However, the spindles are mounted directly to slider mounting plates one or more of which is driven by the spindle drive system. Each slider plate is attached to a slider and each spindle must be adjusted individually on the slider mounting plates mounted to the slider while on the slide to insure proper alignment with the worktable. This is a time consuming process and since the spindles are directly slidable they are continually susceptible to misalignment during operation requiring regular checking and adjustment of each spindle mounting plate on each slider.

While Kosmowski provides for interleaved spindles the presence of a carriage is not possible due to the mounting of multiple spindles directly to the sliders.

None of the related art systems provide a system of interleaved carriages, in which spindles are fixedly mounted to the carriage to minimize misalignment during operation. The present invention permits carriages which are mounted to only two slider mounting plates to engage the sliders for movement of the carriage along the slide, thereby making the overall structure sufficiently robust to minimize misalignment as well as permitting adjustment of the only one slider mounting plate for each carriage to properly align the carriages, while still allowing the positioning of multiple spindles fixedly mounted to the carriage over a plurality of work stations.

Summary of the Invention

The present invention provides a dual carriage system mounted on a machine tool in which the carriages are slideably mounted on a gantry mounted to the machine tool for motion of the carriages along the longitudinal axis of the gantry. The machine tool includes a plurality of worktables positioned at a workstation upon which individual work pieces or stacks of work pieces may be mounted for drilling or other work. The carriages are disposed such that at least a portion of each of the carriages may be moved into a position over the each of the workstations. A plurality of spindles for receiving tools are mounted in a fixed position on each carriage. The spindles are disposed on the carriages such that at least one spindle of each carriage may be positioned over each workstation when the carriages are moved. Either the gantry and the worktables may be stationary or moveable.

Where the worktable is moveable in a first direction, e.g. the Y direction, the carriages are mounted on the gantry such that the carriages are moveable in a second direction perpendicular to said Y direction, e.g. X direction. Each of the spindles has a drilling head which is moveable relative to the carriage in a third direction, such as the Z direction or some angular deviation from the Z direction dependent on the work to be performed, such as angular drilling or edging and the like dependent on the number of axes in the system.

Apparatus for moving the carriages in the X direction, the gantry and the worktable in the Y direction, and the spindle head in the Z direction is provided as is known in the art such as a lead screw drive system, or a linear drive system utilizing a linear motor, or other positioning apparatus. While the gantry and the worktable may be moved in the Y direction, there may be other moveable directions dependent on the number of axes of the system.

In operation the moving apparatus may position the carriages such that at least one of the spindles fixedly mounted on one carriage and at least one of the spindles fixedly mounted on the carriage are each positioned over the same work piece at selected X, and X₂ drilling positions for each of the spindles. The worktable may then be moved in the Y direction to position the work piece at selected Y positions for drilling and other work.

Where the gantry is moveable in a first direction, e.g. the Y direction, the carriages are on the gantry as described above and the spindles are fixedly mounted to the carriages described above.

In operation the moving apparatus may position the carriages such that at least one of the spindles fixedly mounted on one carriage and at least one of the spindles on the other carriage are each positioned over the same work piece at selected X, and X₂ drilling positions for each of the spindles. The gantry may then be moved to position the work piece at selected Y positions for drilling and other work.

Various carriage, worktable and gantry drive systems may be used including but not necessarily limited to lead screw drive system, a linear motor drive system or other drive systems known in the art. Brief Description of the Drawings

Figure 1, is an oblique view of a drilling machine having dual carriages mounted thereon.

Figure 2, is an exploded view of the machine tool showing the gantry slides and the slider mounting plate pairs for receiving the carriages.

Figure 3, is an exploded view of the machine tool showing dual gantry slides and the slider mounting plate pairs for receiving the carriages.

Figure 4, is an exploded view of the machine tool showing linear motor carriage drive system, having carriage drive magnets mounted to each of the slider mounting plate pairs.

Figure 5, is a front view of three spindles two mounted on a first carriage and one mounted on a second carriage.

Figure 6A, is a top down view of a three of work stations on the work table which will have at least one spindle from the carriages of Figure 5 positonable over a work station.

Figure 6B, is a top down view of a two of work stations on the work table which will have at least one spindle from the carriages of Figure 5 positonable over a work station.

Detailed Description of the Preferred Embodiment

Figure 1 shows the drilling machine 1 is mounted on a table 4 and has a plurality of moveable work tables 5. A plurality of drilling spindles 6 and 8 are mounted on the carriages 2 and 3 respectively. The carriages are slideably mounted to a gantry 7.

Figure 2, is an exploded view of the dual carriage system showing the gantry 7 having a pair of slide rails, 9a and 9b mounted thereon upon which is mounted a plurality of slider mounts 10a, 10b, lOc, and lOd. The carriage 2 mounts on slider mounts 10a and lOc and the carriage 3 mounts on slider mounts 10b and lOd. Each of the carriages 2 and 3 is a forked like structure having a driving post and two tines although each may have more or less tines. The two fork tines 2b and 2c are attached to driving post 2a of the carriage 2 and are spaced apart a distance sufficient to permit a similar fork tine 3b to be inserted between tines 2b and 2c. Tine 3c of fork 3 is disposed immediately below fork 2 tine 2c. Each of the tines 3b and 3c is attached to driving post 3a. This arrangement permits a ridged mounting structure of the forks on the sliders 10 such that each fork is supported at two locations on the slider mounts. This allows easy adjustment of the horizontal positioning of the forks relative to the slides 9a and 9b as opposed to adjustment of each spindle. The spindles are mounted to each fork using a plurality of mounting plates Ha through lid for carriage 2 and a plurality of mounting plates 12a through 12d for carriage 3. The mounting plates 11 and 12 form a ridged frame for holding the tines of each of the carriages in a fixed position to one another and provide a rugged structure for mounting the spindles 6 and 8. The spindles 6a through 6d are mounted to mounting plates 11a through lid respectively and spindles 8a through 8d are mounted to mounting plates 12a through 12d respectively. Due to the rugged structure the spindles can be mounted in a fixed position and can withstand the rigors of drilling and repositioning with virtually no need for adjustment. When calibration is required, one need only position all of the spindles for perpendicular motion relative to the carriage frame upon which the particular spindles are mounted without regard to the slide structure.

As shown in Figure 2 each of the carriages 2 and 3 are driven by a lead screw drive system 13, which includes a lead screw 13a for driving carriage 2 and a lead screw 13b for driving carriage 3. Each of the lead screws drives the respective carriages by engaging a lead screw nut 15a and 15b inside the driving posts 2a and 3a respectively. Stepper motors 14a driving lead screw 15a and stepper motor 14b driving lead screw 15b are controlled by the drilling machine tool control system not shown as is known in the art. While a lead screw drive system is illustrated in figure 2 any other drive system may be used. Since the system is a carriage drive system, the spindles may be mounted in fixed positions relative to the carriage. Since each of the carriages is mounted to two sliders and is rigidly held in form by the mounting plates 11 and 12 the adjustment of the carriages on the sliders 10 is relatively easy as only one slider mount need be adjusted. The use of carriages to be mounted to the sliders as described is an ideal way of positively mounting carriages to the gantry. However, heretofore no carriage drive system could implement multiple carriages carrying a plurality of fixed mounted spindles over a plurality of work pieces because the carriages would collide. The forked carriage system of the present invention however, permits the mounting of each of the carriages to the slider as if it were a single solid carriage due to the structural interrelation of the carriage tines and mounting plates but still permits the mounting of an second carriage which cannot collide with the other carriage in operation and permits the tines to interleave. Since each carriage is mounted to only two slider mounts, the arrangement permits proper adjustment of carriages on the sliders of the carriage by repositioning only one of the sliders relative to the carriage when necessary. In addition, the slider mount is isolated from the drilling operation of the spindle and thus tends to remain in place. This saves time and effort in the field. Similarly, the spindles do not need to have continual adjustment as to the sliding mechanism because they are not moveable along the slide they remain fixed on the carriage.

Thus the adjustment of each carriage occurs on only two sliders for each carriage, namely sliders 10a and 10c for carriage 2 and 10b and lOd for carriage 3.

Figure 3 shows an alternative embodiment wherein there are four slides 9a and 9b for slides 10a and lOc and 9c and 9d for slides 10b and lOd. This configuration, permits the slides for each carriage to carry more weight for each carriage and therefor twice the number of spindles may be accommodated in a given machine.

Referring now to figure 4, As an alternative to lead screw drive system, a linear motor drive system is shown. Linear motor elements 16 and 17 are shown mounted to the gantry 7 . Sliders 10a through lOd each have a linear motor magnet element 18 and 19 for interacting with the linear motors 16 and 17 to move the carriages 2 and 3. 18a through 18d are mounted to sliders 10a through lOd and 19a through 19d are also mounted to sliders 10a through lOd.

For multiple pattern drilling, on work pieces located at each workstation. The spindle pairs are initially positioned using the lead screws 13a and 13b independently to set a selected distance between spindles, which corresponds to the distance between each pattern to be drilled on a work piece. Once this distance is set, the carriages may be moved in unison from drilling position to drilling position within each pattern by operating the lead screws in unison. This facilitates a rapid response for adjusting changing drilling patterns on each work piece under command control of a particular work program, the lead screw drive 13a is used to position carriage 2 and the lead screw drive 13b is used to position carriage 3. Pairs of spindles mounted to separate carriages may thus be positioned over single or multiple work pieces or work stations and be operated as if they are on one carriage.

Where the carriage drive system is a linear motor drive 16 an 17 as shown in Figure 4, the magnetic elements mounted on the sliders, i.e. magnetic elements 18b and 18d would be selectively energized to position carriage 3 and magnetic elements 19a and 19c would be selectively energized to position carriage 2. Once the initial positioning of the carriages relative to one another is achieved, all of the magnetic elements 18 and 19 may be energized to move both carriages as a unit to drill the desired patterns.

Figure 5 shows another alternative embodiment which includes the carriage 2 with two tines and the carriage 3 with only a single tine. Two spindles 6a and 6b are mounted to carriage 2. A single spindle 8a is mounted to carriage 3.

This configuration permits the use of a multiple spindle system to work on two kinds of jobs simultaneously. As shown in Figure 6A, three panels may be mounted on the table to form three work stations. As shown in Figure 6B, two panels may be mounted on the table to form two work stations. In this configuration the carriages are driven independent of one another to position spindles over separate work stations. Work pieces 2a and 2b in Figure 6A are drilled in identical patterns by movement of carriage 2 and Work piece 3a is drilled in a different pattern by movement of carriage 3.

In the case of Figure 6B carriage 3 may be idle and the two workpieces are drilled by movement of carriage 2. Or one of the spindles of carriage 2 may be idle and the two work pieces are drilled by motion of both carriage 2 or 3. Repositioning of the gantry permits another row of holes to be drilled in either case. Various other combinations of carriages, workpieces and spindles may be utilized dependent on the specific need of the work environment.

While several specific embodiments of this invention have been described above, those skilled in the art will readily appreciate that many modifications are possible in the specific embodiment, without materially departing from the novel teachings and advantages of this invention. In fact, various methods of operation are possible using some spindles and allowing others to remain idle dependent on the need. In fact, a full compliment of spindles could be used on smaller workpieces, each spindle operating at its own work station on a workpiece with each carriage moving incrementally from hole to hole in unison to produce identical or different work pieces. In addition, although only two tines are shown on each carriage, multiple tines could be interleaved allowing additional flexibility and positioning of carriages and spindles to perform work. Accordingly, all such modifications are intended to be included within the scope of this invention, as defined in the following claims.

Claims

WHAT IS CLAIMED IS:

1. A multiple carriage system for a machine tool comprising: a. a machine tool table; b. a plurality of work stations on said work table; c. a gantry mounted on said table; d. a first carriage slideably mounted on said gantry; e. a plurality of first spindles mounted on said first carriage; such that at least one first spindle is mounted over each work station; f. a second carriage slideably mounted on said gantry; and g. a plurality of second spindles mounted on said second carriage; such that at least one second spindle is mounted over each work station.

2. A multiple carriage system as described in Claim 1 further comprising: a. a first carriage drive system for moving said first carriage; and b. a second carriage drive system for moving said second carriage.

3. A multiple carriage system as described in Claim 2 wherein said first carriage drive system further comprises: a first lead screw drive system for moving said first carriage; and said second carriage drive system further comprises a second lead screw drive system for moving said second carriage.

4. A multiple carriage system as described in Claim 2 herein said first carriage drive system further comprises a first linear motor drive system for moving said first carriage; and said second carriage drive system further comprises a second linear motor drive system for moving said second carriage.

5. A multiple carriage system as described in Claim 2 herein said first carriage drive system and said and said second carriage drive system comprises a linear motor drive system for moving each of said first and second carriages.

6. A multiple carriage system as described in Claim 1 further comprising: a. a first lead screw drive system for moving said first carriage; and b. a second lead screw drive system for moving said second carriage.

7. A multiple carriage system as described in Claim 1 further comprising: a. a first linear motor carriage drive system for moving said first carriage; and b. a second linear motor carriage drive system for moving said second carriage.

8. A multiple carriage system as described in Claim 1 further comprising: a. a first and second carriage drive system for moving said first and second carriages independently of one another.

9. A multiple carriage system for a machine tool comprising: a. a machine tool table; b. a plurality of work stations on said work table; c. a gantry mounted on said table; d. a first carriage slideably mounted on said gantry; e. a plurality of first spindles mounted on said first carriage; such that at least one first spindle is mounted over each work station; f. a second carriage slideably mounted on said gantry; g. a plurality of second spindles mounted on said second carriage; such that at least one second spindle is mounted over each work station; h. a first carriage drive system for moving said first carriage; and i. a second carriage drive system for moving said second carriage.

10. Multiple carriage system for a machine tool comprising: a. a machine tool table; b. a plurality of work stations on said work table; c. a gantry mounted on said table; d. a first carriage slideably mounted on said gantry; e. a plurality of first spindles mounted on said first carriage; such that at least one first spindle is mounted over each work station; f. a second carriage slideably mounted on said gantry; g. a plurality of second spindles mounted on said second carriage; such that at least one second spindle is mounted over each work station; and h. a carriage drive system for moving said first and second carriages.

11. A method for positioning a plurality of carriages each having a plurality of spindles using multiple mounted to a gantry at a plurality of workstations on a machine tool comprising the following steps: a. determining a pattern to be drilled by said plurality of spindles at each work station; b. independently moving a first carriage to a first position such that at least one of said plurality of spindles mounted on said carriage is positioned at a first selected position at each of said workstations; c. independently moving a second carriage to a second position such that at least one of said plurality of spindles mounted on said second carriage is positioned at a second selected position at each of said workstations defining a spindle distance; d. moving said first and second carriages to drill patterns in a work piece at each of said workstations at multiple positions spaced apart said spindle distance.

12. A method for positioning a plurality of carriages each having a plurality of spindles using multiple mounted to a gantry at a plurality of workstations on a machine tool comprising the following steps: a. determining a pattern to be drilled by said plurality of spindles at each work station; b. independently moving a first carriage to a first position such that at least one of said plurality of spindles mounted on said carriage is positioned at a first selected position at each of said workstations; c. independently moving a second carriage to a second position such that at least one of said plurality of spindles mounted on said second carriage is positioned at a second selected position at each of said workstations defining a spindle distance; d. moving said first and second carriages to drill patterns in a work piece at each of said workstations at multiple positions spaced apart said spindle distance.

13. A method for positioning a plurality of carriages, each having a plurality of spindles, mounted to a gantry at a plurality of workstations on a machine tool comprising the following steps: a. determining a pattern to be drilled by said plurality of spindles at each work station; b. independently moving a first carriage of said plurality of carriages to a first position such that at least one of said plurality of spindles mounted on said first carriage is positioned at a first selected position at each of said workstations; c. independently moving a second carriage to a second position such that at least one of said plurality of spindles mounted on said second carriage is positioned at a second selected position at each of said workstations; and d. moving said first and second carriages to drill patterns in a work piece at each of said workstations at multiple positions.

14. A multiple carriage system for a machine tool comprising: a. a machine tool table; b. a gantry mounted on said table; c. a first carriage slideably mounted on said gantry; d. at least one first spindle mounted on said first carriage; such that said at least one first spindle is positioned at a first work station; e. a second carriage slideably mounted on said gantry overlapping said first carriage; and f. at least one second spindle mounted on said second carriage; such that at least one second spindle is positioned at a second work station.

15. A multiple carriage system as described in Claim 14 further comprising: a. a first carriage drive system for moving said first carriage; and b. a second carriage drive system for moving said second carriage.

16. A multiple carriage system as described in Claim 15 wherein said first carriage drive system further comprises: a first lead screw drive system for moving said first carriage; and said second carriage drive system further comprises a second lead screw drive system for moving said second carriage.

17. A multiple carriage system as described in Claim 15 wherein said first carriage drive system further comprises a first linear motor drive system for moving said first carriage; and said second carriage drive system further comprises a second linear motor drive system for moving said second carriage.

18. A multiple carriage system as described in Claim 15 wherein said first carriage drive system and said and said second carriage drive system comprises a linear motor drive system for moving each of said first and second carriages.

19. A multiple carriage system as described in Claim 15 wherein there are a plurality of first work stations and a plurality of spindles mounted to said first carriage each such spindle positioned at a first workstation.

20. A multiple carriage system as described in Claim 19 wherein there are a plurality of spindles mounted to said second carriage and disposed between at least some of said spindles mounted to said first carriage and each such spindle positioned at a second workstation.