Working machine

Patent metadata

Field	Value
Publication number	US-12059790-B2
Application number	US-202217684859-A
Country	US
Kind code	B2
Filing date	Mar 2, 2022
Priority date	Mar 9, 2021
Publication date	Aug 13, 2024
Grant date	Aug 13, 2024

Abstract

A working machine may include: a fan configured to generate an air flow inside a first space; a control unit disposed inside the first space; a partition wall separating the first space from a second space; a first aperture communicating the first space with the second space; and a rib extending from the partition wall and forming an air passage in which the air flow passes, wherein the air passage is positioned between the control unit and the rib. The control unit may include a case housing a circuit board. The control unit may include a first surface facing the rib. In a first direction perpendicular to the first surface, the rib and the first surface may at least partially overlap with each other. A distance between the rib and the first surface may be smaller than a thickness of the case in the first direction.

First claim

What is claimed is:

1. A working machine comprising:
a motor configured to drive a working part;
a fan configured to be driven by the motor and generate an air flow inside a first space;
a control unit disposed inside the first space;
a partition wall separating the first space from a second space;
a first aperture defined in the partition wall and communicating the first space with the second space; and
a rib extending from the partition wall inside the first space and defining an air passage in which the air flow passes, wherein the air passage is positioned between the control unit and the rib,
wherein
the control unit comprises:
a circuit board configured to control actuation of the motor, and
a case housing the circuit board,

the control unit includes a first surface facing the rib,
in a first direction perpendicular to the first surface, the rib and the first surface at least partially overlap with each other, and
a distance between the rib and the first surface is smaller than a thickness of the case in the first direction.

2. The working machine according to claim 1 , wherein
the control unit further comprises a heat dissipating part for heat dissipation, and
the heat dissipating part is exposed to the air passage.

3. The working machine according to claim 2 , wherein the heat dissipating part has a concave-convex shape.

4. The working machine according to claim 1 , wherein the rib is disposed substantially parallel to the first surface.

5. The working machine according to claim 4 , wherein the rib comprises a facing portion that faces ⅓ or more of an area of the first surface.

6. The working machine according to claim 1 , wherein the rib is integrated with the partition wall.

7. The working machine according to claim 1 , wherein the control unit is disposed along a plane substantially perpendicular to the partition wall.

8. The working machine according to claim 1 , wherein the second space is a space outside of the working machine.

9. The working machine according to claim 1 , wherein a width of the first aperture is smaller than the thickness of the case in the first direction.

10. The working machine according to claim 1 , further comprising a second aperture defined in the partition wall and communicating the first space with the second space,
wherein the rib is connected with a portion of the partition wall between the first aperture and the second aperture.

11. The working machine according to claim 1 , further comprising a guide bar,
wherein the working part comprises:
a sprocket configured to be rotated by the motor; and
a saw chain configured to move along a periphery of the guide bar as the sprocket rotates.

12. The working machine according to claim 3 , wherein
the rib is disposed substantially parallel to the first surface,
the rib comprises a facing portion that faces ⅓ or more of an area of the first surface,
the rib is integrated with the partition wall,
the control unit is disposed along a plane substantially perpendicular to the partition wall,
the second space is a space outside of the working machine, and
a width of the first aperture is smaller than the thickness of the case in the first direction,
the working machine further comprises:
a second aperture defined in the partition wall and communicating the first space with the second space; and
a guide bar,

the rib is connected with a portion of the partition wall between the first aperture and the second aperture, and
the working part comprises:
a sprocket configured to rotate by the motor; and
a saw chain configured to move along a periphery of the guide bar as the sprocket rotates.

Assignees

• Makita Corp

Inventors

• Ito Ryosuke
• Ushio Norihiro
• Ojima Akira
• Kashino Yoshiaki

Classifications

• H02K7/145

  Hand-held machine tool · CPC title

• H02K11/33

  Drive circuits, e.g. power electronics (H02K11/38 takes precedence) · CPC title

• H02K9/06

  with fans or impellers driven by the machine shaft · CPC title

• H02K2211/03

  Machines characterised by circuit boards, e.g. pcb · CPC title

• H02K5/18

  with ribs or fins for improving heat transfer · CPC title