Machine-tool device

Patent metadata

Field	Value
Publication number	US-10556333-B2
Application number	US-201415036281-A
Country	US
Kind code	B2
Filing date	Nov 6, 2014
Priority date	Dec 3, 2013
Publication date	Feb 11, 2020
Grant date	Feb 11, 2020

Abstract

A machine-tool device includes at least one control and/or regulation unit. The at least one control and/or regulation unit is configured to (i) at least one of control and/or regulation of a drive unit and (ii) determine at least one actual rotational speed of the drive unit from a signal of at least one sensor element taking the form of an acceleration sensor. The machine-tool device further includes at least one sensor unit which includes the at least one sensor element taking the form of the acceleration sensor.

First claim

The invention claimed is:

1. A drilling hammer comprising:
a drive unit;
a tool socket operably connected to the drive unit and configured to be rotated by the drive unit;
a striking-mechanism device operably connected to the drive unit and configured to drive a striking-impulse element via a drive torque of the drive unit to generate a striking impulse having a periodic acceleration;
an acceleration sensor configured to generate an acceleration signal based on the periodic acceleration; and
at least one control and/or regulation unit operably connected to the drive unit and the acceleration sensor, the control and/or regulation unit configured to (i) control rotation of the drive unit at a set rotational speed, (ii) determine an actual rotational speed of the drive unit from a frequency of the periodic acceleration of the striking-impulse element, (iii) determine a difference between the set rotational speed and the actual rotational speed, and (iv) adapt the actual rotational speed to correspond to the set rotational speed based on the determined difference.

2. The drilling hammer as claimed in claim 1 , wherein the control and/or regulation unit is further configured to adjust the actual rotational speed of the drive unit as a first function of the acceleration signal of the acceleration sensor.

3. The drilling hammer as claimed in claim 1 , further comprising a current sensor operably connected to the control and/or regulation unit and configured to generate a current signal based on a current consumed by the drive unit.

4. The drilling hammer as claimed in claim 3 , wherein the control and/or regulation unit is further configured to adjust the actual rotational speed of the drive unit as a first function of the acceleration signal of the acceleration sensor and as a second function of the current signal of the current sensor.

5. The drilling hammer as claimed in claim 3 , further comprising a voltage sensor operably connected to the control and/or regulation unit and configured to generate a voltage signal based on a voltage of the drive unit.

6. The drilling hammer as claimed in claim 5 , wherein the control and/or regulation unit is further configured to adjust the actual rotational speed of the drive unit as a first function of the acceleration signal of the acceleration sensor, as a second function of the current signal of the current sensor, and as a third function of the voltage signal of the voltage sensor.

7. The drilling hammer as claimed in claim 1 , wherein the control and/or regulation unit includes at least one voltage and/or current regulator configured to adapt the actual rotational speed of the drive unit based on a characteristic quantity of the actual rotational speed determined from the acceleration signal of the acceleration sensor.

8. A method for at least one of controlling and regulating a rotational speed of a drive unit of a drilling hammer including the drive unit, a tool socket operably connected to the drive unit,
a striking-mechanism device operably connected to the drive unit, an acceleration sensor, and at least one control and/or regulation unit operably connected to the drive unit, the method comprising:
controlling rotation of the drive unit at a set rotational speed with the at least one control and/or regulation unit;
driving a striking-impulse element of the striking-mechanism device via a drive torque of the drive unit to generate a striking impulse having a periodic acceleration;
determining an actual rotational speed of the drive unit from a frequency of the periodic acceleration of the striking-impulse element with the at least one control and/or regulation unit;
determining a difference between the set rotational speed and the actual rotational speed with the at least one control and/or regulation unit; and
adapting the actual rotational speed to correspond to the set rotational speed based on the determined difference with the at least one control and/or regulation unit.

9. The method as claimed in claim 8 , wherein:
the control and/or regulation unit is configured to adapt a parameter characteristic of the drive unit to adapt the set rotational speed of the drive unit, and
the parameter characteristic of the drive unit is saved in a memory unit of the control and/or regulation unit.

10. The drilling hammer as claimed in claim 1 , wherein the periodic acceleration is parallel to an axis of rotation of the drive unit.

11. The method as claimed in claim 8 , further comprising:
sensing the acceleration with the acceleration sensor along an axis that is parallel to an axis of rotation of the drive unit.

Assignees

• Bosch Gmbh Robert

Inventors

• Wirnitzer Bernd
• Sprenger Helge
• Keinath Hagen Philipp

Classifications

• B25D2250/221

  Sensors · CPC title

• B25D11/005 Primary

  Arrangements for adjusting the stroke of the impulse member or for stopping the impact action when the tool is lifted from the working surface · CPC title

• B25F5/00

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

• B25D2250/201

  for speed, e.g. drilling or percussion speed · CPC title

• B25D11/00 Primary

  Portable percussive tools with electromotor {or other motor} drive · CPC title