Adjustable shuttle stop apparatus

• US 20030000358A1
• Filed: 06/21/2001
• Published: 01/02/2003
• Est. Priority Date: 06/21/2001
• Status: Active Grant

• Current Assignee: HEM Incorporated
• Original Assignee: HEM Incorporated
• Inventors: Neall, Timothy M., Harris, Gerald R.
• Granted Patent: US 6,698,159 B2
• Time in Patent Office: Days
• US Class Current: 83/247
• CPC Class Codes: B23D 47/04 of devices for feeding, positioning, clamping, or rotating work
• CPC Class Codes: B23D 55/043 for conveying work to the sawing machine
• CPC Class Codes: B27B 27/02 arranged laterally and parallel with respect to the plane of the saw blade
• CPC Class Codes: Y10T 83/445 With work-moving clamp jaw
• CPC Class Codes: Y10T 83/446 With means to initiate tool feed by same control impulse
• CPC Class Codes: Y10T 83/4465 With work-stopping abutment in sensing means
• CPC Class Codes: Y10T 83/4513 Work feed means halted by means on tool or tool support
• CPC Class Codes: Y10T 83/4556 By adjustment of fixed stop
• CPC Class Codes: Y10T 83/4597 With means to control magnitude of work-feed increment or work acceleration
• CPC Class Codes: Y10T 83/461 With abutment to position work being fed with respect to cutter
• CPC Class Codes: Y10T 83/4632 Comprises a work-moving gripper
• CPC Class Codes: Y10T 83/4645 With means to clamp work during dwell
• CPC Class Codes: Y10T 83/6531 Movement by screw means
• CPC Class Codes: Y10T 83/6532 Movement by rack and pinion or pawl

Abstract

A adjustable shuttle stop apparatus for use in controlling feeding of material to a machining operation on a machine tool, such as a band saw. The apparatus comprises a feed conveyor, a band saw adjacent to the feed conveyor, a shuttle vise movably disposed on the feed conveyor, and an adjustable stop on the feed conveyor for adjusting a distance between the stop and the shuttle vise and for stopping the shuttle vise at the cutting position. The adjustable stop compensates for undesired movement of the shuttle vise caused by clamping the workpiece such that the distance between the stop and the shuttle vise remains substantially constant. This allows for a consistent cut length of the workpiece on subsequent cutting cycles. Different embodiments of the adjustable stop are disclosed along with a method of use of the apparatus.

Claims

1. A material cutting apparatus comprising:

a feed conveyor;

a machine tool adjacent to said feed conveyor;

a shuttle vise movably disposed on said feed conveyor, said shuttle vise being adapted for clamping a workpiece on said feed conveyor when in a clamping position and moving the workpiece to a cutting position adjacent to the machine tool; and

an adjustable stop on said feed conveyor for adjusting a distance between said stop and said shuttle vise and stopping said shuttle vise at said cutting position.

2. The apparatus of claim 1 wherein:

said adjustable stop is adapted for adjusting said distance in an amount approximately equal to movement of said shuttle vise caused by clamping the workpiece.

3. The apparatus of claim 2 further comprising:

an encoder adapted for generating a signal in response to said movement of said shuttle vise; and

an actuator for moving said adjustable stop in response to said signal.

4. The apparatus of claim 3 further comprising a controller for receiving said signal and transmitting said signal to said actuator.

5. The apparatus of claim 4 further comprising a positional sensor for sensing a position of said adjustable stop and transmitting a positional signal in response thereto to said controller.

6. The apparatus of claim 5 wherein said controller transmits a signal for varying said cutting position of said shuttle vise in response to said positional signal.

7. The apparatus of claim 2 further comprising a positional sensor adapted for sensing a position of said adjustable stop.

8. The apparatus of claim 7 wherein said positional sensor is a transducer.

9. The apparatus of claim 7 wherein said positional sensor is a switch.

10. The apparatus of claim 1 wherein said adjustable stop comprises:

a wedge having an angled face opposite said shuttle vise; and

an actuator for moving said wedge transversely with respect to said feed conveyor.

11. The apparatus of claim 10 wherein said actuator is characterized by a linear motion device.

12. The apparatus of claim 10 wherein said apparatus further comprises a bumper disposed on said shuttle vise, said bumper having an angled face corresponding to the angled face on said wedge, wherein movement of said wedge results in varying the distance between the face on said bumper and the face on said wedge.

13. The apparatus of claim 1 wherein said adjustable stop comprises:

a stepped member having a plurality of faces directed toward said shuttle vise; and

an actuator for moving said stepped member transversely with respect to said feed conveyor.

14. The apparatus of claim 13 wherein said actuator is characterized by a linear motion device.

15. The apparatus of claim 13 wherein said apparatus her comprises a bumper attached to said shuttle vise and having a face thereon;

wherein, said actuator is adapted for moving said stepped member such that a selected one of said faces is aligned with said face on said bumper.

16. The apparatus of claim 1 wherein said adjustable stop comprises:

a sleeve;

a shaft having an end with a face thereon directed toward said shuttle vise, said shaft being threadedly connected to said sleeve such that rotation of said shaft varies the distance between said face and said shuttle vise; and

a prime mover for rotating said shaft.

17. The apparatus of claim 16 further comprising:

a bumper attached to said shuttle vise and adapted for engaging said face on said end of said shaft.

18. The apparatus of claim 16 further comprising:

a first pulley connected to said shaft;

a second pulley connected to said prime mover; and

a belt interconnecting said first and second pulleys.

19. The apparatus of claim 16 further comprising a spring engaging said shaft and biasing said shaft longitudinally with respect to said sleeve for eliminating play in a threaded connection between said shaft and sleeve.

20. The apparatus of claim 16 further comprising:

a switch; and

a cam rotatable by said prime mover and having a cam lobe thereon for engaging said switch when said cam is in a predetermined position.

21. The apparatus of claim 20 wherein said predetermined position corresponds to a longitudinal mid-point position of said shaft.

22. The apparatus of claim 1 wherein said adjustable stop comprises:

an eccentric cam having a cam surface thereon directed toward said shuttle vise; and

an actuator for rotating said cam.

23. The apparatus of claim 22 wherein said actuator is a reversible step motor.

24. The apparatus of claim 22 wherein said apparatus further comprises a bumper attached to said shuttle vise and having a face thereon;

wherein, said cam surface is adapted for engagement by said face.

25. The apparatus of claim 1 wherein said machine tool is a band saw.

26. The apparatus of claim 1 further comprising an actuator for moving said adjustable stop.

27. The apparatus of claim 26 wherein said actuator is linear motion device.

28. The apparatus of claim 26 wherein said actuator is a pressure-actuated cylinder.

29. The apparatus of claim 26 wherein said actuator is connected to said stop by a screw device.

30. The apparatus of claim 26 wherein said actuator is connected to said stop by a rack and pinion gear system.

31. On a machine of the type comprising a feed conveyor, a material cutting device adjacent to the feed conveyor, a shuttle vise longitudinally movably disposed on said feed conveyor and adapted for clamping a workpiece when in a clamping position and moving the workpiece to a cutting position under the material cutting device, the improvement comprising:

a stop disposed on said feed conveyor for limiting movement of said shuttle vise toward said material cutting device, the distance between said stop and said shuttle vise being adjustable in response to movement of said shuttle vise when clamping the workpiece.

32. The improvement of claim 31 further comprising:

an encoder adapted for generating a signal in response to said movement of said shuttle vise; and

an actuator for moving said stop in response to said signal.

33. The improvement of claim 31 further comprising a positional sensor adapted for sensing a position of said stop.

34. The improvement of claim 33 wherein said positional sensor is a transducer.

35. The improvement of claim 33 wherein said positional sensor is a switch.

36. The improvement of claim 31 wherein:

said stop comprises a wedge having an angled face opposite said shuttle vise; and

an actuator adapted for moving said wedge transversely with respect to said feed conveyor.

37. The improvement of claim 36 further comprising a bumper disposed on said shuttle vise, said bumper having an angled face corresponding to the angled face on said wedge, wherein movement of said wedge results in a variation of the distance between the face on said bumper and the face on said wedge.

38. The improvement of claim 31 wherein:

said stop comprises a stepped member having a plurality of faces directed toward said shuttle vise; and

an actuator adapted for moving said stepped member transversely with respect to said feed conveyor.

39. The improvement of claim 38 further comprising a bumper attached to said shuttle vise and having a face thereon;

wherein, said actuator is adapted for moving said stepped member such that a selected one of said plurality of faces is aligned with said face on said bumper.

40. The improvement of claim 31 further comprising:

an actuator comprising;

a sleeve;

a shaft threadingly engaged with said sleeve and rotatable therein; and

a prime mover for rotating said shaft;

wherein;

said stop comprises an end of said shaft directed toward said shuttle vise.

41. The improvement of claim 38 further comprising a bumper attached to said shuttle vise and adapted for engaging said end.

42. The improvement of claim 38 wherein said actuator further comprises:

a first pulley connected to said screw;

a second pulley connected to said prime mover, and

a belt interconnecting said first and second pulleys.

43. The improvement of claim 40 further comprising a spring engaging said shaft and baising said shaft longitudinally with respect to said sleeve for eliminating play in a threaded connection between said shaft and sleeve.

44. The improvement of claim 40 further comprising;

a switch; and

a cam rotatable by said prime mover and having a cam lobe thereon for engaging said switch when said cam is in a predetermined position.

45. The improvement of claim 44 wherein, said predetermined position corresponds to a longitudinal mid-point positon of said shaft.

46. The improvement of claim 31 wherein:

said stop comprises an eccentric cam having a cam surface directed toward said shuttle vise; and

an actuator for rotating said cam.

47. The improvement of claim 46 wherein said actuator is a reversible step motor.

48. The improvement of claim 46 wherein said apparatus further comprises a bumper attached to said vise and having a face thereon;

wherein, said cam surface is adapted for engagement by said face.

49. The improvement of claim 31 wherein:

said machine tool is a band saw; and

said material cutting device is a band saw blade.

50. The apparatus of claim 31 further comprising an actuator for moving said adjustable stop.

51. The apparatus of claim 50 wherein said actuator is linear motion device.

52. The apparatus of claim 50 wherein said actuator is a pressure-actuated cylinder.

53. The apparatus of claim 50 wherein said actuator is connected to said stop by a screw device.

54. The apparatus of claim 50 wherein said actuator is connected to said stop by a rack and pinion gear system.

55. A method of cutting a workpiece comprising the steps of:

(a) providing a cutting apparatus comprising a feed conveyor, a machine tool adjacent to said feed conveyor, a shuttle vise movably disposed on said feed conveyor and adapted for clamping the workpiece when in a clamping position and moving the workpiece to a cutting position adjacent to the machine tool, and a stop for stopping the shuttle vise at the cutting position;

(b) detecting movement of said shuttle vise resulting from clamping the workpiece; and

(c) adjusting said stop on said feed conveyor for compensating for said movement of said shuttle vise such that a distance between said shuttle vise and said stop remains substantially constant.

56. The method of claim 55 wherein step (c) comprises:

generating a signal in response to said movement of said shuttle device; and

transmitting said signal to an actuator for moving said adjustable stop in response to said signal.

57. The method of claim 55 wherein step (c) comprises moving a wedge on said stop transversely with respect to said feed conveyor.

58. The method of claim 55 wherein step (c) comprises moving a stepped member having a plurality of faces thereon transversely with respect to said feed conveyor.

59. The method of claim 55 wherein step (c) comprises rotating a shaft connected to said stop.

60. The method of claim 55 wherein step (c) comprises rotating a cam such that a cam surface on said cam is moved with respect to said feed conveyor.