Threaded member tightening tool and counting apparatus

Patent metadata

Field	Value
Publication number	US-10967487-B2
Application number	US-201815880703-A
Country	US
Kind code	B2
Filing date	Jan 26, 2018
Priority date	Sep 8, 2015
Publication date	Apr 6, 2021
Grant date	Apr 6, 2021

Abstract

Provided is a threaded member tightening tool capable of returning a count value in linkage with reverse driving by the threaded member tightening tool and only when a threaded member to be removed by the reverse driving has been counted as a tightened threaded member. A computing unit of a motor-driven screwdriver is switchable between a counting mode in which the computing unit counts the number of tightened threaded members and holds the counted number as a count value and a count return mode for returning the count value to a one-preceding count value. The computing unit returns the count value to a one-preceding count value based on the fact that the engaging element fitting unit has been driven in the reverse direction when the computing unit has been switched to the count return mode.

First claim

The invention claimed is:

1. A threaded member tightening tool comprising:
a tool body having an engaging element fitting unit to which a threaded member engaging element is to be fitted, and an electric motor rotationally driving the engaging element fitting unit;
a forward-reverse rotation switching unit for switching a direction of rotation of the engaging element fitting unit by the electric motor between a forward direction and a reverse direction;
a computing unit switchable between a counting mode in which the computing unit counts a number of threaded members tightened with a threaded member engaging element fitted to the engaging element fitting unit and rotated by the electric motor and holds the counted number as a count value and a count return mode for returning the count value to a one-preceding count value; and
a mode switching unit for switching the computing unit from the counting mode to the count return mode;
wherein the computing unit returns the count value to a one-preceding count value in response to the engaging element fitting unit having been driven in the reverse direction with the computing unit having been switched to the count return mode, and the computing unit does not change the count value in response to the engaging element fitting unit having been driven in the reverse direction with the computing unit remaining in the counting mode and not having been switched to the count return mode.

2. The threaded member tightening tool of claim 1 , wherein the computing unit returns the count value to a one-preceding count value when the engaging element fitting unit has been driven in the reverse direction in response to starting of the electric motor in a state where the direction of rotation of the engaging element fitting unit has been set in the reverse direction through the forward-reverse rotation switching unit and where the computing unit has been switched to the count return mode by actuation of the mode switching unit.

3. The threaded member tightening tool of claim 1 , wherein the computing unit cancels the count return mode when the computing unit has returned the count value to a one-preceding count value.

4. The threaded member tightening tool of claim 1 , wherein the computing unit cancels the count return mode when setting of the direction of rotation of the engaging element fitting unit is changed from the reverse direction during the count return mode.

5. The threaded member tightening tool of claim 1 , wherein the computing unit cancels the count return mode when the engaging element fitting unit is driven in the reverse direction during the count return mode.

6. The threaded member tightening tool of claim 1 , further comprising a count return mode canceling unit, wherein the computing unit cancels the count return mode when the count return mode canceling unit is actuated during the count return mode.

7. The threaded member tightening tool of claim 1 , further comprising:
a count return mode display part displaying that the computing unit has been switched to the count return mode.

8. The threaded member tightening tool of claim 1 , wherein the computing unit allows selection of a mode of counting a number of tightened threaded members from between a count-up mode and a count-down mode,
and wherein when the count-up mode has been selected, the computing unit increments the count value by 1 upon completion of tightening of a threaded member and decrements the count value by 1 when the engaging element fitting unit has been driven in the reverse direction during the count return mode, and when the count-down mode has been selected, the computing unit decrements the count value by 1 upon completion of tightening of a threaded member and increments the count value by 1 when the engaging element fitting unit has been driven in the reverse direction during the count return mode.

9. A counting apparatus for use in combination with a threaded member tightening tool having an engaging element fitting unit to which a threaded member engaging element is to be fitted, an electric motor capable of driving the engaging element fitting unit in either of a forward direction and a reverse direction, and a signal output unit, the counting apparatus being configured to be communicatively connected to the signal output unit, the counting apparatus comprising:
a computing unit switchable between a counting mode in which the computing unit counts a number of tightened threaded members by receiving from the signal output unit a tightening completion signal indicating that the threaded member tightening tool has completed tightening of a threaded member and holds the counted number as a count value and a count return mode for returning the count value to a one-preceding count value; and
a mode switching unit for switching the computing unit from the counting mode to the count return mode;
wherein the computing unit returns the count value to a one-preceding count value in response to the computing unit having received from the signal output unit a drive signal indicating driving of the electric motor in the reverse direction with the computing unit having been switched to the count return mode, and the computing unit does not change the count value in response to the computing unit having received from the signal output unit the drive signal indicating driving of the electric motor in the reverse direction with the computing unit remaining in the counting mode and not having been switched to the count return mode.

10. The counting apparatus of claim 9 , wherein the computing unit returns the count value to a one-preceding count value when receiving from the signal output unit a signal indicating that the engaging element fitting unit has been driven in the reverse direction in response to starting of the electric motor in a state where the computing unit has received from the signal output unit a signal indicating that a forward-reverse rotation switching unit provided in the threaded member tightening tool has switched a driving direction of the electric motor to the reverse direction and where the computing unit has been switched to the count return mode.

11. The counting apparatus of claim 9 , wherein the computing unit cancels the count return mode when the computing unit has returned the count value to a one-preceding count value.

12. The counting apparatus of claim 11 , wherein the computing unit cancels the count return mode when receiving a signal indicating that the driving direction of the electric motor has been changed from the reverse direction during the count return mode.

13. The counting apparatus of claim 9 , wherein the computing unit cancels the count return mode when receiving the drive signal indicating driving of the electric motor in the reverse direction during the count return mode.

14. The counting apparatus of claim 9 , further comprising a count return mode canceling unit, wherein the computing unit cancels the count return mode when the count return mode canceling unit is actuated during the count return mode.

15. The counting apparatus of claim 9 , further comprising:
a count return mode display part displaying that the computing unit has been switched to the count return mode.

16. The counting apparatus of claim 9 , wherein the computing unit allows selection of a mode of counting a number of tightened threaded members from between a count-up mode and a count-down mode,
and wherein when the count-up mode has been selected, the computing unit increments the count value by 1 when receiving the tightening completion signal and decrements the count v

Assignees

• Nitto Kohki Co

Inventors

• Hita Hirokazu
• Otsuka Kenji

Classifications

• B25F5/00

  Details or components of portable power-driven tools not particularly related to the operations performed and not otherwise provided for · CPC title

• B25B23/147 Primary

  specially adapted for electrically operated wrenches or screwdrivers · CPC title

• B25B21/00 Primary

  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 title

• B25B23/14

  Arrangement of torque limiters or torque indicators in wrenches or screwdrivers (couplings for transmitting rotation or clutches F16D; devices for measuring torque per se G01L) · CPC title

• B25F5/001

  Gearings, speed selectors, clutches or the like specially adapted for rotary tools · CPC title