Miter saw

• US 8,230,768 B2
• Filed: 01/18/2005
• Issued: 07/31/2012
• Est. Priority Date: 01/16/2004
• Status: Active Grant

• Current Assignee: Koki Holdings Co., Ltd.
• Original Assignee: Hitachi KOKI Company Limited (Koki Holdings Co., Ltd.)
• Inventors: Ozawa, Hiromi, Oka, Eisaku, Takano, Nobuhiro, Terashima, Hideaki
• Primary Examiner(s): Ashley, Boyer D
• Assistant Examiner(s): FLORES SANCHEZ, OMAR
• Application Number:
  US11/036,140
• Publication Number:
  US 20050155477A1
• Time in Patent Office: 2,751 Days
• Field of Search: 835/81, 835/221.5, 835/221.6, 835/221.1, 835/222.2, 834/713, 834/71, 834/771
• US Class Current: 83/522.11
• CPC Class Codes: B23D 45/044 the saw blade being adjustable according to angle of cut B23D45/025 takes precedence
• CPC Class Codes: B23D 59/002 for the position of the saw blade mounting for swiveling or tilting a circular saw blade B27B5/36; portable power-driven circular saws with adjustment for cutting depth or amount of tilting B27B9/02
• CPC Class Codes: Y10T 83/849 With signal, scale, or indicator
• CPC Class Codes: Y10T 83/853 Indicates tool position
• CPC Class Codes: Y10T 83/8773 Bevel or miter cut

Abstract

A miter saw having good workability without decrease in angle visibility is disclosed. The miter saw includes a display unit provided on a turntable. The display unit 600 is positioned between an operating handle protruding outward from the turntable and a rotation axis of the turntable. The display unit is positioned below the upper surfaces of a base and the turntable not so as to protrude above the upper surface of the turntable. The display unit displays an inclination angle of a circular saw blade with respect to the upper surface of the base and a rotation angle of the turntable with respect to the base in a line.

Claims

1. A digital miter saw comprising:

a base having a workpiece placement surface for positioning a workpiece thereon;

a fence fixed to the base and having a contact surface to which the workpiece is forced;

a circular saw portion for rotatably supporting a circular saw blade;

a supporting member for pivotably supporting the circular saw portion about a pivot shaft extending substantially parallel to an axial direction of the circular saw blade;

a turntable connected to the supporting member, and having an upper surface cooperating with the workpiece placement surface of the base to support the workpiece, the turntable being capable of rotating about a rotating axis with respect to the base, thereby changing an angle between the contact surface of the fence and the circular saw blade;

rotation angle detection means provided on a portion adjacent to a rotation axis of the turntable and contacted to both the turntable and the base, and provided below the workpiece placement surface, for detecting a rotation angle of the turntable with respect to the base to output an electrical signal indicating the rotation angle;

digital display means for digitally displaying the rotation angle, the digital display means being provided below the workpiece placement surface so as not to protrude above the workpiece placement surface of the base; and

control means for generating an electrical signal for displaying the rotation angle on the display means based on the output signal of the rotation angle detection means,

wherein the digital display means is provided on the turntable, and

wherein the turntable includes an operating handle protruding outward, and the digital display means is provided between the operating handle and the rotation axis of the turntable.

2. The digital miter saw as claimed in claim 1, wherein the workpiece placement surface includes an upper surface of the base,

the supporting member is connected to the base through the turntable, the supporting member being able to incline about an inclination axis fixed to the turntable with respect to the base, the inclination axis being on a plane including the upper surface of the base and being parallel to the upper surface, and

an inclination angle of the circular saw blade with respect to the upper surface of the base is changeable.

3. The digital miter saw as claimed in claim 1, wherein the rotation axis is a rotation shaft to rotate integrally with the turntable, and

the rotation angle detection means detects a rotation amount of the rotation shaft with respect to the base.

4. The digital miter saw as claimed in claim 1, wherein the rotation axis is a rotation shaft fixed to the base, and

the rotation angle detection means detects a rotation amount of the turntable with respect to the rotation shaft.

5. The digital miter saw as claimed in claim 1, wherein the digital display means includes a display surface and a removable transparent cover to cover the display surface, and the transparent cover is positioned below the workpiece placement surface so as not to protrude above the workpiece placement surface of the base.

6. The digital miter saw as claimed in claim 1, wherein the base includes a front half portion for positioning the workpiece thereon and a rear half portion closer to the supporting member, the front half and the rear half portions being divided by a line passing through the rotation axis of the base, and

the digital display means is positioned at a predetermined position on the front half portion of the base.

7. The digital miter saw as claimed in claim 6, wherein the digital display means has a display surface extending in an inclined direction from a vertical direction.

8. The digital miter saw as claimed in claim 1, wherein the base includes a front half portion including the contact surface of the fence and a rear half portion closer to the supporting member, the front half and the rear half portions being divided by a line passing through the contact surface of the fence, and

the digital display means is positioned at a predetermined position on the front half portion of the base.

9. The digital miter saw as claimed in claim 8, wherein the digital display means has a display surface extending in an inclined direction from a vertical direction.

10. The digital miter saw according to claim 1,

wherein the digital display means does not include power switches for the miter saw.

11. The digital miter saw according to claim 1, further comprising a reset, disposed proximate to said digital display, for resetting said displayed rotation angle.

12. The digital miter saw as claimed in claim 2, further comprising inclination angle detection means to detect the inclination angle to generate a signal indicating the inclination angle, wherein the control means displays the inclination angle on the digital display means based on an output signal from the inclination angle detection means.

13. The digital miter saw as claimed in claim 12, wherein the digital display means includes a display surface to display the rotation angle and the inclination angle display thereon in a line.

14. The digital miter saw as claimed in claim 13, wherein the digital display means has a unit structure, and the digital display means has an inclination mark and a rotation mark provided on an outer frame near the display surface at positions corresponding to an inclination angle display portion and a rotation angle display portion, respectively, thereby clarifying that the digital display means displays the inclination angle and the rotation angle.

15. The digital miter saw as claimed in claim 13, wherein the digital display means includes a removable transparent cover to cover the display surface, the transparent cover being positioned below the workpiece placement surface so as not to protrude above the workpiece placement surface of the base.

16. The digital miter saw as claimed in claim 13,

wherein the digital display means includes an inclination mark related to the inclination angle display and a rotation mark related to the rotation angle display, and wherein only the inclination angle and the rotation angle are displayed digitally in a line, adjacent the inclination mark and the rotation mark, respectively, to minimize the size of the display means.

17. The digital miter saw according to claim 13, further comprising:

a reset, disposed proximate to said digital display, for resetting at least one of the angles displayed.

18. The digital miter saw according to claim 17, wherein said reset is operable to reset one or both of said displayed angles.

19. The digital miter saw according to claim 18, wherein said reset comprises separate reset members, each operable to reset one of the inclination angle and the rotation angle.

20. The digital miter saw according to claim 17, wherein said digital display comprises an LCD.

21. The digital miter saw according to claim 20, further comprising a backlight.

22. The digital miter saw as claimed in claim 1, wherein the control means is provided on the turntable.

23. The digital miter saw as claimed in claim 1, wherein the rotation angle detection means is covered by a protective box located below the workpiece placement surface, said protective box being configured to provide dust protection and electrical insulation for said rotation angle detection means.

24. The digital miter saw as claimed in claim 1, wherein the rotation angle detection means comprises a potentiometer.

25. The digital miter saw as claimed in claim 23, wherein the rotation angle detection means comprises a potentiometer.

26. The digital miter saw as claimed in claim 1, further comprising means, located below the workpiece placement surface, for protecting the rotation angle detection means from dust and for providing electrical insulation for the rotation angle detection means.

27. The digital miter saw as claimed in claim 24, wherein the potentiometer is located on the center of the rotation axis of the turntable, below the workpiece placement surface.

28. The digital miter saw as claimed in claim 25, wherein the potentiometer is located on the center of the rotation axis of the turntable, below the workpiece placement surface.