Hand-held device

• US 5,879,111 A
• Filed: 11/12/1997
• Issued: 03/09/1999
• Est. Priority Date: 11/11/1996
• Status: Expired due to Term

• Current Assignee: Hilti Aktiengesellschaft (Hilti Martin Family Trust)
• Original Assignee: Hilti Aktiengesellschaft (Hilti Martin Family Trust)
• Inventors: Thiel, Arno, Stock, Maximilian, Kristen, Ferdinand
• Primary Examiner(s): Howell, Daniel W.
• Assistant Examiner(s): Tabaddor, Rouzbeh
• Application Number:
  US08/967,808
• Time in Patent Office: 482 Days
• Field of Search: 408/6, 408/8, 408/9, 408/124
• US Class Current: 408/6
• CPC Class Codes: B25D 16/003 Clutches specially adapted therefor
• CPC Class Codes: B25D 2211/003 Crossed drill and motor spindles
• CPC Class Codes: B25D 2211/068 Crank-actuated impulse-driving mechanisms
• CPC Class Codes: B25F 5/00 Details or components of portable power-driven tools not particularly related to the operations performed and not otherwise provided for
• CPC Class Codes: F16D 2121/22 for releasing a normally applied brake
• CPC Class Codes: F16D 49/00 Brakes with a braking member co-operating with the periphery of a drum, wheel-rim, or the like similar clutches F16D13/10
• CPC Class Codes: F16D 59/02 spring-loaded and adapted to be released by mechanical, fluid, or electromagnetic means
• CPC Class Codes: F16D 63/006 Positive locking brakes
• CPC Class Codes: Y10T 408/14 Responsive to condition of Tool or tool-drive
• CPC Class Codes: Y10T 408/165 to control Tool rotation
• CPC Class Codes: Y10T 408/65 Means to drive tool

Abstract

A motor-operated hand-held device (1), such as a drilling device, has a rotary spindle (6) located within and projecting out of a housing (2). Rotational movement of a driving motor (8) is transmitted to a tool (7) secured to the end of the rotary spindle (6). A safety device (11) within the housing (2) prevents a deflection of the housing about an axis (A) of the rotary spindle (6) in the event the tool (7) becomes suddenly jammed. The safety device (11) can be activated by a detection device (12) if the tool (7) becomes jammed. An overload slip clutch (10) is provided in the drive (9) between the driving motor (8) and the rotary spindle (6). The safety device (11) is arranged in series with the overload slip clutch (10) and is located in the drive (9) adjacent the overload slip clutch (10). When activated, the safety device (11) couples the housing (2) with the drive (9) for the rotary spindle so that the housing (2) and the drive (9) are fixed with respect to rotation relative to one another.

Claims

1. Motor operated hand-held device comprising a housing (2), an axially extending rotary spindle (6) mounted in and projecting out of said housing (2) for transmitting rotational movement from a driving motor (8) located in said housing to a tool (7), said rotary spindle (6) and said tool (7) having a common axis (A), a safety device (11) located within said housing (2) for preventing a deflection of said housing (2) about the axis (A) of said rotary spindle (6) in the event during operation of said hand-held device said tool (7) becomes suddenly jammed, a detection device (12) in said housing (2) for activating said safety device (11) in the event said tool (7) is jammed, an overload slip clutch (10) positioned upstream of a means (9) for conveying the driving action of said driving motor (8) to said rotary spindle (6), said safety device (11) arranged adjacent said overhead slip clutch (10), and when said safety device is activated, the safety device couples said housing with said means (9) for driving said rotary spindle so that said housing (2) and said means (9) are fixed with respect to rotation relative to one another.

2. Motor-operated hand-held device as set forth in claim 1, wherein said safety device (11) is activated electro-mechanically when jamming of said tool (7) is detected.

3. Motor-operated hand-held device, as set forth in claim 2, wherein said safety device (11) comprises a spring-loaded thrust element (110) which, when said hand-held device is switched off, couples the housing (2) with the means (9) so that they are fixed with respect to rotation relative to one another.

4. Motor-operated hand-held device, as set forth in claim 3, wherein said spring-loaded thrust element (110) is positioned in a magnetic field of a magnet coil (112) supplied with current during operation of said hand-held device and which current is switched off when jamming of the tool (7) is detected and the safety device (11) is activated.

5. Motor-operated hand-held device, as set forth in claims 1, 2, 3 or 4, wherein said safety device (11) provides a positive engagement between said housing (2) and said means (9) for driving said rotary spindle (16) and comprises at least two locking elements (110, 93) cooperating with one another in a positive engagement when said safety device is activated, and one of said locking elements being connected with said housing (2), and the other said locking element forming a part of said means (9) for driving said rotary spindle (6).

6. Motor-operated hand-held device, as set forth in claims 1, 2, 3 or 4, wherein said safety device (11), when activated, provides a frictional connection between said housing (2) and said means (9) for driving said rotary spindle (6) and comprises at least one brake shoe (113) associated with said housing (2) and arranged for frictional engagement with a rotating shaft (92) of said means (9) when jamming of said tool (7) takes place.

7. Motor-operated hand-held device, as set forth in claim 6, wherein said brake shoe (11) has a curved friction surface corresponding to a curvature of a surface of said shaft (92).

8. Motor-operated hand-held device, as set forth in claim 6, wherein said brake shoe (113) is replaceable.