DE1813587U - ELECTRIC MACHINE TOOL WITH PROTECTIVE INSULATION. - Google Patents

Description

7 433 * -!

* fr. ■■■ -. ■
Lr / Lm IU-Kr,
11/6/1959-

Attachment to

ROBERT BOSCH GMBH, Stuttgart W, Brettseheidstrasse 4

Electric hand tool with protective insulation

The invention fee draws on an electric hand tool !! »- machine with protective insulation «whose drive motor is seated in an insulating housing and a fan wheel is mounted on its armature shaft Generating a flow of cooling air in the motor housing carries "

With such devices, the safety against contact with live parts can depend on the state in which they are viewed. There are creepage distances on the surfaces of the insulating material housing ", with 'internally ventilated hand-held door ducts', dust, too, is sucked in with the cooling air,". layers "whose conductivity" can reach a. · .... The danger of creeping distances = ·. "Education 1st. 'with those'Haindwerkzeugm & sehinen _s ... which have a gear housing made of metal * The = invention was based on the G@da.nke, along the inner circumference of the with, its open face ■ facing the gear housing Insulating · = material housing create a zone that is free from creeping current by arranging the fan wheel within the insulating material housing and using the cooling air flow conveyed by the fan wheel to protect this zone free from creeping current from contamination <,

Λ .; ■ -. . · ". ■; ·; · -. ^ .- ■; ■ ·.. ·. ■■. ■ · ■■ -. ■■■■

Robert Bosch GmbH Lr / Lm R ₀ -Nr ₀

Stuttgart. ■ .- · '. . : ..6011.1959

% Erf induhgsgemäss'wird'dies achieved in that between the fan wheel and f the front side of the insulating environmentally.

'. ■ closed motor stand an air guide ring is arranged »" from 'consists of elastic plastic and one of the ring plane

has at least approximately vertically protruding edge with which the ". ring" is tightly clamped against the. motor housing ο

In the drawing, as an exemplary embodiment, an electric hand «

-.drilling machine partly Indian view and partly in section shown -; . - - '"- ^

The hand drill has a molded plastic motor housing * -. . 10, a hand screwed to "its rear, front face" -

*. handle Hv and one made of molded insulating material, on the front

End face of the motor housing attached, bearing plate 12, the one - 'Gear housing 13 cast from light metal carries * In the engine -. housing 10 1st the stand 15 of the An = composed of sheet metal drive motor of the hand drill attached with screw 16 while

* the anchor IT on the one hand-in * the end of the 'on the handle side. ■ ■ Motor housing with the help of a not shown in the drawing

* '-' ball bearing is in bearing <, "The end of the armature shaft on the gearbox side - ■ "· 18 carries an insulating sleeve · 20 * which is placed in the armature pinion 21 <is taken. On the -Änkerrltzel 21, the inner ring 22 is one

Pulled on the ball bearing, the outer ring 23 of which is fastened in the end shield ^{12 at ~ v ν.}

shaft. . ^II ^ - gear housing 13 protruding drilling spindle 25 ".- Duron the insulating, I material sleeve 20 is the anchor shaft so isolated from the gear,

- ^x that in the event of an iron connection in anchor 1? no tension on the _N. Gear housing 13 can reach «so that a long enough creep

. Current-free zone between dem. bearing plate 12 and the face of the -i '. The stator 15 it can be produced is the motor housing 10. t'- at its section on the gearbox side so far against the gearbox- "■ -

Robert Bosch GmbH Lr / ϊΛΐ Ro-No ₀

Stuttgart. ■■ ν '.' ·. '' .6o.il ". 1959 -

housing LJ5 or _o the bearing plate 12 preferred that the Ankerwe Henri trzel patch fan 28 at its extensive full "- is constantly covered by the motor housing" The / the operation of the hand drill sponsored cooling air stream is benutzt- to the fan 28, the inner The catch surface of the zone of the motor housing that covers the fan wheel is to be kept free of dust and dirt in order to achieve this. Luftleitringscheibe 30 is provided, which faces the radial blades 31 -des "Lüfterrädes a small distance" Air-1-eitscheibe is made of elastic plastic and. Has a -senkrecht projecting from the Ringebe.ne hand 32 _o This is in an in Wall of the motor housing "from its end face." pierced annular groove J4 inserted such that the edge close to the motor housing rests _o In this way, the cooling air flow is guided so that check circumferentially on the interior of the motor housing between the bearing plate 'and- the Luf tleitseheibe even when operating in strong' dusty environments not the current leakage promoting ■ layers of dirt can _{build up o}

Claims (1)

Electric power tool machine with protective insulation _p. Whose drive motor sits in an insulating housing and a fan wheel on its armature shaft. Generating a cooling air flow in the motor housing, characterized in that between .den Ulfterrad- (28) and the end face of the motor stator (15) enclosed by the insulating material housing (10) an air guide ring (30) is arranged, which consists of elastic plastic and one of the ring plane has at least approximately vertically protruding hats (52), "with" which the ring is tightly clamped against the motor housing «- · Hand machine tool according to claim 1, characterized in that _p .that the fan wheel (28) is arranged at least with its Grogsteil, measured in the axial direction within the insulating material Sehaufelbrelte _0th '. -, -. ■ Hand tool machine according to Claims 1 and 2 _e characterized in that the fan wheel (28) with its blades reaches close to the wall of the insulating material housing surrounding the fan wheel. . . '