Hand-held electric machine tool comprising a dust collection container and a level indicator

• US 20060178087A1
• Filed: 11/08/2004
• Published: 08/10/2006
• Est. Priority Date: 12/05/2003
• Status: Abandoned Application

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Hesse, Juergen, Wuensch, Steffen
• Application Number:
  US10/549,135
• Publication Number:
  US 20060178087A1
• Time in Patent Office: Days
• US Class Current: 451/8
• CPC Class Codes: A47L 9/19 Means for monitoring filtering operation
• CPC Class Codes: B23Q 11/0046 by sucking
• CPC Class Codes: B23Q 11/0071 dust collectors for hand tools
• CPC Class Codes: B24B 55/10 specially designed for portable grinding machines, e.g. hand-guided
• CPC Class Codes: Y02P 70/10 Greenhouse gas [GHG] capture, material saving, heat recovery or other energy efficient measures, e.g. motor control, characterised by manufacturing processes, e.g. for rolling metal or metal working

Abstract

An electric hand-held power tool is described that has a machine housing (11) with an integral dust-ejection connection (15) and a dust collection container (16) attached thereto. To ensure, when working with the electric hand-held power tool, that the dust collection container (16) is emptied in time when full, a fill level indicator is provided that indicates, at the least, the maximum amount of dust allowed in the dust collection container (16). The fill level indicator (20) is preferably integrated in the machine housing (11) and includes a pressure sensor (21) that measures the pressure in the dust-ejection connections (15), and a display unt (22) that is actuated as a function of the pressure measured (FIG. 1).

Claims

1. An electric hand-held power tool with a machine housing (11) with an integral dust-ejection connection (15) and a dust collection container (16) attached to the dust-ejection connection (15), characterized by a fill level indicator (20) that indicates, at the least, the maximum allowed dust load of the dust collection container (16).

2. The electric hand-held power tool as recited in claim 1, wherein the fill level indicator (20) is integrated in the machine housing (11).

3. The electric hand-held power tool as recited in claim 2, wherein the fill level indicator (20) includes a pressure sensor (21) that measures the pressure in the dust-ejection connection (15), the pressure sensor generating an output value that is proportional to the measured pressure, and including a display unit (22) controlled by the output value.

4. The electric hand-held power tool as recited in claim 3, wherein the pressure sensor (21) is located in the machine housing (11) and detects the pressure in the dust-ejection connection (15) via a duct (24) in the machine housing (11) that leads into the dust-ejection connection (15).

5. The electric hand-held power tool as recited in claim 2,

wherein the display unit (22) is visible on the machine housing (11), being located preferably above a handle (17) formed on the machine housing (11).

6. The electric hand-held power tool as recited in claim 3,

wherein the pressure sensor (21) is an electromechanical pressure sensor, with which a pressure chamber (42) bounded by a diaphragm (32) or a displacement piston (41) is acted upon by the pressure in the dust-ejection connection (15) and which is preloaded via a spring (38) against the pressure in the pressure chamber (42), and a contact member of a break contact located in the circuit of an electrical display unit (22) is coupled to the diaphragm (32) or displacement piston (41), the contact member closing when the diaphragm (32) or displacement piston (41) is displaced to a specified extent.

7. The electric hand-held power tool as recited in claim 6, wherein the maximum displacement of the diaphragm (32) or displacement piston (41) is adjusted such that, when the pressure in the pressure chamber (42) corresponds to the pressure that exists in the dust-ejection connection (15) when the dust collection container (16) is filled to the maximum level, the break contact closes.

8. The electric hand-held power tool as recited in claim 3,

wherein the pressure sensor (21) is a mechanical pressure sensor with a displacement piston (41) acted upon by the pressure in the dust-ejection connection (15), and the display unit (22) is a device that displays the displacement travel of the displacement piston (41) as the fill level amount in the dust collection container (16).

9. The electric hand-held power tool as recited in claim 3,

wherein the pressure sensor (21) is a piezoelectric pressure-measuring cell.

10. The electric hand-held power tool as recited in claim 1,

wherein a fan wheel (14) of a suction fan is located in the machine housing (11), the fan wheel (14) drawing in dust from the surface of a machined workpiece and blowing it into the dust collection container (16) via the dust-ejection connection (15).