Electromechanical gear selection device comprising a stepping motor

Patent metadata

Field	Value
Publication number	US-2020116253-A1
Application number	US-201816627210-A
Country	US
Kind code	A1
Filing date	Jun 22, 2018
Priority date	Jun 29, 2017
Publication date	Apr 16, 2020
Grant date	—

Abstract

A method for selecting a gear in the transmission of a power tool having an electric motor. The method includes the following steps of changing an operating device from a first position to a second position in order to select a gear in the transmission; detecting a signal via at least one sensor corresponding to the second position of the operating device; sending the signal to a controller; changing the rotational speed of the electric motor from a first value to a second value via the controller; changing the operating device from the second position to a third position; changing the stepping motor from a first position to a second position corresponding to the third position of the operating device; and changing a shift fork from a first position to a second position in order to change from a first gear to a second gear.

First claim

What is claimed is:

1 - 5 . (canceled)

6 . A method for selecting a gear in a transmission of a power tool, the power tool having an electric motor for generating and transmitting a torque to the transmission as well as a controller for setting a rotational speed of the electric motor, the transmission having an operating device for selecting a gear in the transmission, a shift fork for engaging the gear in the transmission as well as a stepping motor for transmitting a movement of the operating device to the shift fork, the operating device having at least one signal transmitter as well as at least one sensor for receiving at least one signal from the at least one signal transmitter, the method comprising the following steps:
changing the operating device from a first position to a second position in order to select a gear in the transmission; detecting the at least one signal via at least one sensor and corresponding to the second position of the operating device; sending the at least one signal to the controller; changing the rotational speed of the electric motor from a first value to a second value via the controller; changing the operating device from the second position to a third position; changing the stepping motor from a stepping motor first position to a stepping motor second position corresponding to the third position of the operating device; and changing the shift fork from a shift fork first position to a shift fork second position in order to change from a first gear to a second gear.

7 . A power tool for carrying out the method according to claim 6 , comprising the transmission, the electric motor for generating and transmitting the torque to the transmission, the controller for setting the rotational speed of the electric motor, the transmission having the operating device for selecting the gear in the transmission, the shift fork for engaging the gear in the transmission and the stepping motor for transmitting a movement of the operating device to the shift fork for engaging the gear in the transmission, the operating device having the at least one signal transmitter as well as the at least one sensor for receiving the at least one signal from the at least one signal transmitter.

8 . The power tool as recited in claim 7 wherein the signal transmitter is configured in the form of a magnet and the sensor is configured in the form of a Hall sensor.

9 . The power tool as recited in claim 7 wherein in the transmission contains a shifting energy storage, as a result of which a force can be applied onto the shift fork in order to pretension the shift fork to make a transition from the shift fork first position to the shift fork second position.

10 . A transmission for a power tool for carrying out the method according to claim 6 , the transmission comprising: the operating device for selecting the gear in the transmission, the shift fork for engaging the gear in the transmission as well as the stepping motor for transmitting a movement of the operating device to the shift fork, the operating device having the at least one signal transmitter as well as the at least one sensor for receiving at least one signal from the at least one signal transmitter.

11 . A core drilling machine comprising the transmission as recited in claim 10 .

12 . A core drilling machine comprising the power tool as recited in claim 7 .

13 . The method as recited in claim 6 wherein the power tool is a core drilling machine.

Assignees

• Hilti Ag

Inventors

• Hanslmeier Xaver
• Van Taack-Trakranen John

Classifications

• B25F5/001 Primary

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

• F16H61/682

  with interruption of drive · CPC title

• F16H61/0213 Primary

  characterised by the method for generating shift signals · CPC title

• F16H61/2807

  using electric control signals for shift actuators, e.g. electro-hydraulic control therefor  (F16H61/30, F16H61/32 take precedence) · CPC title