ELECTRICALLY POWERED GARDENING TOOL

• US 20140007717A1
• Filed: 07/02/2013
• Published: 01/09/2014
• Est. Priority Date: 07/04/2012
• Status: Active Grant

• Current Assignee: Makita Corporation
• Original Assignee: Makita Corporation
• Inventors: KATO, Kazuya, KOIDE, Yuki
• Granted Patent: US 9,357,711 B2
• Time in Patent Office: Days
• US Class Current: 74/49
• CPC Class Codes: A01G 2003/0461 with reciprocating knives
• CPC Class Codes: A01G 3/053 motor-driven
• CPC Class Codes: A01G 3/067 Motor-driven shears for lawns
• CPC Class Codes: F16H 21/18 Crank gearings; Eccentric gearings
• CPC Class Codes: Y10T 74/18248 Crank and slide

Abstract

An electrically powered gardening tool of the type which includes a speed-reduction gear mounted in place to be driven by operation of an electric motor, a crank-cam in the form of overlapped eccentric disk plates fixed to a bottom surface of the speed-reduction gear by means of connecting pins for rotation therewith, and a pair of relatively reciprocating shear blades assembled with the eccentric disk plates. In the gardening tool, an elastic bushing is disposed in a mounting hole formed in the speed-reduction gear or each eccentric disk plate of the crank-cam for engagement with the connecting pins fixed to the eccentric disk plate or the speed-reduction gear, and a stopper is provided to restrict deformation of the elastic bushing caused by load applied to the crank-cam.

Claims

1. An electrically powered gardening tool comprising a speed-reduction gear mounted in place to be driven by operation of an electric motor, a crank-cam in the form of overlapped eccentric disk plates fixed to a bottom surface of the speed-reduction gear by means of connecting pins for rotation therewith, and a pair of relatively reciprocating shear blades assembled with the eccentric disk plates, wherein an elastic bushing is disposed in a mounting hole formed in the speed-reduction gear or each eccentric disk plate of the crank-cam for engagement with the connecting pins fixed to the eccentric disk plate or the speed-reduction gear, and wherein a stopper is provided to restrict deformation of the elastic bushing caused by load applied to the crank-cam.

2. An electrically powered gardening tool as claimed in claim 1, wherein said stopper is in the form of a cylindrical stopper made of hard material and being formed smaller in diameter than said elastic bushing and coupled with said connecting pins in the mounting holes respectively.

3. An electrically powered gardening tool as claimed in claim 1, wherein said stopper is in the form of a cylindrical stopper made of hard material and being formed larger in inner diameter than the outer diameter of each of said connecting pins and engaged with the inner surface of each of said mounting holes.

4. An electrically powered gardening tool as claimed in claim 1, wherein said connecting pins each are a stepped pin formed with a large diameter portion smaller in diameter than said elastic bushing, and wherein said stopper is in form of the large diameter portion of said stepped pin.

5. An electrically powered gardening tool as claimed in claim 1, wherein said mounting holes each are formed with a small diameter portion larger in diameter than each of said connecting pins and smaller than said elastic bushing, and wherein said stopper is in the form of the small diameter portion of each of said mounting holes.

6. An electrically powered gardening tool as claimed in claim 1, wherein said stopper is in the form of a stopper pin fixed to the bottom of said speed-reduction gear to be concentrically inserted into an engagement hole formed in said crank-cam, and wherein said engagement hole is formed larger in diameter than said stopper pin to be spaced from said stopper pin in a clearance smaller than thickness of said elastic bushing.