Screw Tightening Tool

• US 20130126202A1
• Filed: 08/01/2011
• Published: 05/23/2013
• Est. Priority Date: 07/30/2010
• Status: Abandoned Application

• Current Assignee: Hitachi KOKI Company Limited (Koki Holdings Co., Ltd.)
• Original Assignee: Hitachi KOKI Company Limited (Koki Holdings Co., Ltd.)
• Inventors: Oomori, Katsuhiro, Nakamura, Mizuho, Ito, Yutaka, Nishikawa, Tomomasa, Mashiko, Hironori, Sumi, Atsushi, Ogura, Masayuki, takeda, Takeshi
• Application Number:
  US13/698,478
• Publication Number:
  US 20130126202A1
• Time in Patent Office: Days
• US Class Current: 173/217
• CPC Class Codes: B25B 21/00 Portable power-driven screw or nut setting or loosening tools; details or components, e.g. casings, bodies, of portable power-driven tools not particularly related to the operation performed B25F5/00; for mounting or dismounting wheels B60B29/006; Attachments for drilling apparatus serving the same purpose machines B23P19/06
• CPC Class Codes: B25B 21/02 with means for imparting impact to screwdriver blade or nut socket
• CPC Class Codes: B25B 23/1475 for impact wrenches or screwdrivers

Abstract

An screw tightening tool (1) includes: a handle part (22) to be held by a user; a trigger (25); a power supplying section (6, 7) that supplies an electrical power in accordance with an operated amount of the trigger; and a motor (3) that rotates in accordance with the electrical power supplied from the power supplying section. The power supplying section supplies the motor with a preventing electrical power for preventing the motor from rotating with respect to the handle part when a predetermined condition is satisfied.

Claims

1. A screw tightening tool comprising:

a handle part to be held by a user;

a trigger;

a power supplying section that supplies an electrical power in accordance with an operated amount of the trigger; and

a motor that rotates in accordance with the electrical power supplied from the power supplying section,

wherein the power supplying unit supplies the motor with a preventing electrical power for preventing the motor from rotating with respect to the handle part when a predetermined condition is satisfied.

2. The screw tightening tool according to claim 1, wherein the power supplying section supplies the motor with the preventing electrical power when the operated amount of the trigger falls into a predetermined range.

3. The screw tightening tool according to claim 2, wherein the power supplying section supplies the motor with a constant electrical as the preventing electrical power.

4. The screw tightening tool according to claim 1, wherein the power supplying section supplies the motor with the preventing electrical power during a predetermined period since an operation of the trigger has been stopped.

5. The screw tightening tool according to claim 1, wherein the power supplying section supplies the motor with the preventing electrical power when the motor rotates with respect to the handle part without an operation of the trigger.

6. The screw tightening tool according to claim 1, wherein the motor is a brushless motor having a stator and a rotor that rotates in accordance with the electrical power supplied to the stator, and

wherein the power supplying unit supplies the stator with the preventing electrical power.