Circular saw unit

• US 5,257,570 A
• Filed: 01/11/1993
• Issued: 11/02/1993
• Est. Priority Date: 07/16/1990
• Status: Expired due to Fees

• Current Assignee: Ryobi Limited (Techtronic Industries Company Limited)
• Original Assignee: Ryobi Limited (Techtronic Industries Company Limited)
• Inventors: Nakamura, Norifumi, Miyamoto, Kouichi, Shiotani, Takeshi
• Primary Examiner(s): PHAN, HIEN HUY
• Application Number:
  US08/002,675
• Time in Patent Office: 295 Days
• Field of Search: 83/397, 83/471.3, 83/473, 83/477.1, 83/478, 83/490, 83/699
• US Class Current: 83/471.3
• CPC Class Codes: B23D 45/044 the saw blade being adjustable according to angle of cut B23D45/025 takes precedence
• CPC Class Codes: B27B 5/208 the saw blade being mounted on a hanging arm or at the end of a set of bars, e.g. parallelograms
• CPC Class Codes: B27G 19/02 for circular saws
• CPC Class Codes: B27G 5/02 for sawing mitre joints; Mitre boxes guide fences for timber in sawing machines B27B27/00
• CPC Class Codes: Y10T 83/7697 Tool angularly adjustable relative to work-support
• CPC Class Codes: Y10T 83/7705 Adjustable angular relationship
• CPC Class Codes: Y10T 83/7726 By movement of the tool
• CPC Class Codes: Y10T 83/7788 Tool carrier oscillated or rotated
• CPC Class Codes: Y10T 83/9469 Adjustable

Abstract

A circular saw unit capable of changing an angle for cutting a workpiece comprises a base member, a rotary table which is rotatably mounted on the base member and on which the workpiece is placed, a hinge having one end supported to the rotary table and, a bracket member or support arm member pivotally connected to the other end of the hinge. The hinge comprises a lower hinge member having one end supported to the rotary table and an upper hinge member having one end pivotally connected to the other end of the lower hinge member and having the other end connected pivotally to the bracket member. The hinge may have a quadrilateral link mechanism for restricting a lower limit position of the circular saw and for assuring a horizontal movement of the circular saw during a cutting operation.

Claims

1. A circular saw unit including a circular saw for cutting a work piece, comprising:

a base member;

a rotary table which is rotatably mounted on the base member and on which the work piece is placed;

a hinge supported by the base member; and

a bracket member pivotably connected to the hinge to support a circular saw;

said hinge comprising a first hinge member having a first end pivotably supported by the base member so as to be swingable in lateral directions about a horizontal axis parallel to the rotary table and a second hinge member having a first end pivotably connected to a second end of the first hinge member so as to be swingable in front and rear directions of the rotary table, a second end of the second hinge member pivotably connected to the bracket member, and a hinge locking portion comprising said second end of said first hinge member, said first end of said second hinge member, and a hinge locking means for releasably and selectively locking said second hinge member to said first hinge member so as to maintain said second hinge member in one of a plurality of predetermined rotational positions with respect to said first hinge member when the hinge locking means is locked, and to permit said second hinge member to rotate freely with respect to said first hinge member when said hinge locking means is released.

2. A circular saw unit according to claim 1, wherein said first end of said first hinge member is supported by said rotary table by means of a bolt and nut assembly.

3. A circular saw unit according to claim 1, wherein said second end of said first hinge member and said first end of said second hinge member are pivotably connected by a pivot member to each other.

4. A circular saw unit according to claim 1, wherein said hinge locking means comprises a hinge fastening member movably held in one of said first hinge member and second hinge member and selectively inserted into one of a plurality of pin fitting holes formed in the other of said first hinge member and said second hinge member.

5. A circular saw unit including a circular saw for cutting a work piece, comprising:

a base member;

a rotary table which is rotatably mounted on the base member and on which the work piece is placed;

a hinge supported by the base member; and

a bracket member pivotably connected to the hinge;

said hinge comprising a first hinge member supported by the base member, a second hinge member having a first end pivotably connected to an upper end of said first hinge member so as to be swingable in front and rear directions of the rotary table and a second end pivotably connected to the bracket member, and a hinge locking portion comprising said upper end of said first hinge member, said first end of said second hinge member and a hinge locking means for releasably and selectively locking said second hinge member to said first hinge member at one of a plurality of predetermined rotational positions, such that when said hinge locking means is locked, said second hinge member is maintained in said one of the plurality of predetermined rotational positions, and when said hinge locking means is released, said second hinge member is freely pivotable with respect to said first hinge member.

6. A circular saw unit according to claim 5, wherein said hinge locking means comprises a hinge fastening member movably held in one of said first and second hinge members and selectively inserted into one of a plurality of pin fitting holes formed in the other of said first and second hinge members.

7. A circular saw unit according to claim 6, wherein said hinge further comprises a spring, said spring urging said hinge fastening member toward the pin fitting holes.

8. A circular saw unit according to claim 6, wherein said hinge fastening member has a knob, wherein the hinge fastening member is removed from said one of the plurality of pin fitting holes when said knob is pulled outwardly.

9. A circular saw unit according to claim 5, wherein said hinge further comprises a spring, said spring located at the second end of the second hinge member so as to urge the bracket member upwardly.