DE7713994U1 - ORBITAL GRINDER - Google Patents

Description

R. 3 0 ^ 2
Bü / Sch February 18, 1977

ROBERT BOSCH GMBH, STUTTGART Orbital sander

Summary

An orbital sander is proposed which is used for grinding preferably flat surfaces. The orbital sander has a handle, a motor housing, a drive motor built into it, a grinder housing, which is preferably made of plastic and is formed in one piece with the motor housing and the handle, one with the grinder housing via four movable, rubber elastic Sanding plate connected to columns and two clamps for the sanding paper to be clamped onto the sanding plate, whereby the free lever arm of the clamping bracket is arranged between two columns.

State of the art

The invention is based on an orbital sander according to the Genre of the main claim. It's an orbital sander known as the clamping device two as a two-armed lever

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has trained clamps, the clamp arm and free lever arm arranged between the grinder housing and the sanding plate are. In this orbital sander, the movable connection is part formed between the grinder housing and the grinding plate as a gifiiimielastic, hollow cylindrical jacket, the the crank drive of the grinding plate protects against dust, which at the same time prevents the heat developed in the crank drive with special needs. Since the well-known orbital sander has a metallic grinder housing that radiates the heat loss from the sanding plate drive and also emits it to the outside air through heat conduction, the encapsulation of the drive provided by the movable connecting part makes this known even during prolonged operation Orbital sander not noticeable in a disturbing way.

In another known orbital sander, there is the movable connection between the sander housing and the sanding plate formed by four rubber, elastic columns. The clamping device for the sandpaper is a two-armed lever with a clamping arm and a manually operable free lever arm, the free lever arm of which, however, is arranged above the grinder housing is. This free lever arm is therefore accessible to touch, including accidental contact, by human hands, which is a considerable one Represents the possibility of an accident.

(_ Advantages of the invention

The orbital sander according to the invention with the characterizing features of the main claim has the advantage that the clamping bracket arrangement is accident-proof and also permitted, to attach a suction frame in a simple manner to the slide housing, and that at the same time the movable connection between the grinder housing and the sanding plate

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• heated air from the drive parts moving the sanding plate not disabled.

The measures listed in the subclaims are an advantageous development and improvement of the im Main claim specified orbital sander possible. Especially The design of the slider housing as a plastic part is advantageous; the orbital sander after registration can thus be designed to be fully insulated and is particularly light and inexpensive in terms of production technology Design of the grinder housing can also be used in continuous operation. The arrangement of the columns offers further advantages As far as possible from the drive of the grinding plate and close to the outer boundary of the grinding plate, and thus connected the formation of the clamping device in the form of two clamping brackets, which are arranged between each two of the columns are. As a result, the best possible connection between the grinder housing and the grinding plate is achieved. When the bearings and the free lever arms of the clamping bracket also are moved as close as possible to the center of the sanding plate, the orbital sander3 will run particularly smoothly achieved.

drawing

In the drawing, two examples of the prior art and an embodiment are shown and in FIG explained in more detail below. Show it

Fig. 1 shows a first orbital sander of a known type in partial representation, sectioned;

Pig. 2 shows a second orbital sander of a known type in partial representation, in section;

Pig. 3 the orbital sander according to Pig. 2 in spatial Partial representation;

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,? ig. 4 shows an orbital sander according to the claims of the present application in elevation, in section;

FIG. 5 shows the orbital sander according to FIG. 4 in three-dimensional form Partial representation.

description

In the following, "above" means the sighting towards the drive motor, and "below" means the direction towards the grinding plate.

The orbital sander shown in Fig. 1 has a motor housing 1 made of plastic with a drive motor 2 built into it, a metallic grinder housing 3 and a grinding plate 4. The grinder housing protrudes a little over the grinding plate. A suction frame 3 ¹ is slipped over the grinder housing in such a way that it surrounds the sanding plate and, with a sealing lip 3 ″, is approximately flush with the sanding paper, not shown, which is stretched onto the sanding plate. The grinding plate can be displaced by the motor via a V-belt 5 and a crank drive 6 in an oscillating movement describing small circles. The grinding plate 4 is movably connected to the grinder housing 3 by a cuff 7 made of rubber-elastic material and designed in the form of a hollow cylinder .

Two two-armed clamping brackets 10 and 11 are on the two narrow ■ Sides of the sanding plate are each supported on a bearing block 12 and 13 and have a clamp arm 14, 15 and a free one Lever arm 16, 1? on. One helical spring 18, 19 each designed as a torsion spring holds the clamping arm against the upper boundary surface pressed onto the sanding plate, where it is used to clamp the sandpaper. The clamps are located with all their! parts between the sanding plate and

the grinder housing, the free lever arms extend in the direction of the drive of the sanding plate.

The known orbital sander shown in Figures 2 and 3 has a grinder housing 20 and a grinding plate 21 which is slightly longer than the grinder housing; The grinder housing and the grinding plate are connected to one another by 4-pillars 22. The columns 22 are designed as rubber-elastic Hohlaylinders. Two clamping brackets 23 are mounted with bearing brackets 24 at the narrow ends of the grinding plate 21. Your clamping arms 25 are designed as torsion springs coil springs 26 from the outside to the inside against a . Hand 27 pressed the sanding plate where they clamp the sandpaper 28. The free lever arms 29 of the clamping brackets are located above the grinder housing 20.

The orbital sander shown in FIGS. 4 and 5 according to the application has a plastic sander housing 30 which is formed from one piece with the motor housing and the handle and projects a little beyond the sanding plate 31 attached below. The grinding plate can be set in oscillating motion by the drive motor 33 via a crank mechanism 32. Four rubber-elastic columns 34 are arranged as far outside as possible between the grinder housing and the grinding plate. A clamping bracket 35 is rotatably mounted on bearing blocks 36 between the pairs of columns on one narrow side of the grinding plate. The clamp strap each have a clamping arm 37 and a for driving directed towards the free lever arm 38. By each designed as a torsion coil spring 39, the clamp arm _t 37 printed from above against the upper covering surface of the grinding plate where it holds the sandpaper not shown. By "applying pressure to the free lever arm 38, which is led out laterally to the longer edge of the sanding plate and is accessible from above through a cutout in the grinder housing, the clamping arm can be lifted and the sandpaper can be released from the clamp for replacement.

Claims (6)

R. "3 8 8 2 Bü / Sch February 18, 1977 ROBERT BOSCH GMBH, STUTTGART Claims 1. Orbital sander with a handle, with one in a motor housing built-in drive motor, with a grinder housing, one connected to the grinder housing via at least one movable connecting part Sanding plate and a clamping device attached to the sanding plate for the clamping device to be clamped onto the sanding plate Sandpaper, characterized in that as a connecting part 4- pillars (34-) and as a clamping device at least one as a two-armed Lever-shaped clamping bracket (35) is provided, which has a 'Klensa arm (37) and a manually operated free lever arm (38) has, wherein the free lever arm (38) is arranged at least for the most part between the grinder housing (30) and the grinding plate (31). 2. Orbital sander according to claim 1, characterized in that the Grinder housing (30) is made of plastic. 3. Orbital sander according to claim 2, characterized in that the Grinder housing in one piece with the motor housing and the handle is trained. 7713994 0itt7i τ "· - Γ · :: · ^{Il:;?"; :} 38 _c 2 f 4-. Orbital sander according to claim 1, 2 or 3, characterized in that the columns (34) are at a distance from the drive (32) of the ski. platbe (31) and near the outer boundary of the grinding plate are arranged> i, and that the clamping device is designed in the form of two clamping brackets (35) which are arranged between two columns (3 ² O). 5. Orbital sander according to claim 4, characterized in that the bearings and the free lever arms (38) of the clamping bracket (35) are arranged stretching from the clamping arm (37) to the center of the grinding plate (31) ki- ¹ * © ^r . 6. Orbital sander according to claim 5 »characterized in that J the columns (3 ^) are essentially cylindrical and consist of rubber-elastic material. 7713994 011171