DE8225299U1 - ADDITIONAL HANDLE FOR A HAND MACHINE TOOL - Google Patents

Description

R. ¹⁸ ° 35

27.8. 1982 Vo / Wl

ROBERT BOSCH GMBH, 7OOO Stuttgart 1

State of the art additional handle for a handheld power tool

The invention is based on an additional handle according to the preamble of the main claim. In a known handle of this type, the tension screw that tightens the tensioning band around the extension of the housing of the hand tool is screwed into a threaded sleeve which is injected into the hollow handle part, which is designed as a plastic molded part. During tensioning, the handle part is rotated against the hollow body. This additional handle, which can be reliably attached to the power tool, has a handle part, the length of which is adjusted so that the drilling torques that normally occur with a medium-weight rotary hammer from k to 8 kg when using drill diameters of 6 mm to about 20 mm can be safely held. However, drilling tools with a very large diameter - for example drill bits with a diameter of 100 mm - are being used more and more in such hammer drills. The response torque of the safety clutch of the hammer drill must be adapted to these large drill diameters. However, it is then so high that the rotary hammer when the drill gets stuck from the operating

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man can only be held with difficulty. Therefore one has with another known handle (DE-GM 79 27 713) » the one, however, with two rigid half-shells that can be screwed together, the one around the extension like a clamp of the housing of the handheld power tool are placed, can be attached to the handheld power tool, the handle already designed telescopically extendable. At the-! eem handle, the rod is cylindrical and

in one injected into the handle part made of plastic Sleeve led. In the state of use, the rod is thus against axial movement with respect to the handle part secured that the rod carries an eccentric at its free end, which at'Vertrehung the handle part ι a frictional engagement of the two with respect to the eccentric

; Parts causes. This has the disadvantage that in particular

the hand machine tool is set in strong vibrations as a result of the tool movement, the frictional engagement can solve, making the additional handle to the worst Time can be pushed together unintentionally. The disadvantages of the first mentioned reappear here known additional handle. In addition, the two rigid half-shells existing clamping device only in connection with a precisely matched diameter Extension of a hand machine tool can be used.

Advantages of the invention

The additional handle designed according to the invention with The characterizing features of the main claim has the advantage over hand machine tools with the housing extension that does not exactly match in diameter can be securely clamped, but still the possibility offers a telescopic extension. The handle part is safe from ^ r in all operating positions

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positively locked against the rod. The handle part can be designed in a particularly cost-effective manner as a pure plastic part; the injection of metal sleeves in the plastic is not necessary.

The features and measures listed in the subclaims are advantageous developments and improvements the additional handle specified in the main claim is possible. The fact that the locking body in extension a sliding sleeve, which closes the mouths of the passages in its locking position, radially outwards can evade when the Srhiebehülse after, axially different against the force of a closing spring in its locking position is brought, a secure locking of the rod relative to the handle part is effected. These However, locking can be achieved by deliberate actuation of the sliding sleeve, which is a separate component from the Handle part is designed to be picked up easily and simply again.

drawing

Exemplary embodiments of the invention are shown in the drawing and explained in more detail in the description below. In Figures 1 and 2 is a first embodiment of an auxiliary handle, shown in the figures, and k and 5 two further embodiments.

Description of the exemplary embodiments

The additional handle 1 shown is intended to be clamped on a cylindrical extension 2 of the housing

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a hand machine tool, for example a drilling _Ä ,

hammers. J is located in the cylindrical extension 2

usually the storage for the tool spindle of the hand machine tool. A flat tension band 3, normally made of steel, is placed around the extension 2. The ends of the tension band are held in a slot k in the head 5 of a tension screw 6 by a fastening pin 7. The pin is prevented from falling out by its is guided in ^ groove-shaped recesses 11 in the inner wall of a hollow body 8 at both ends.

The tensioning strap 3, which extends around the circumference of the extension 2 aer hand power tool, is over two im Deflection shoulders 9 arranged inside the hollow body 8, which are parallel to the axis of the extension 2 extend. The deflection shoulders 9 are located in the course of an adapted to the outer shape of the extension 2, as a seat 10 formed inner surface 11 of the hollow body

The tension screw 6 is guided in a bore which is arranged at the base of the Γ interior of the hollow body 8 and opens out on the end face 13 of the hollow body 8 facing away from the deflection shoulders 9. The tension screw 6 is screwed into a threaded sleeve 1U which is integrally formed on a rod 15 with a hexagonal cross section. On the front side, the threaded sleeve 1U is supported on the front side 13 of the hollow body 8.

The hexagonal rod 15 is longitudinally displaceable in an associated central guide bore 16 of one from Plastic existing handle body 17 out. The cross section of the guide bore 16 has a small amount of play larger than the cross section of the rod 15

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The rod 15 has three locking recesses which extend around the entire circumference of the rod and are designed as annular grooves 18 on (Figure 2). In radial passages of a cylindrical extension 19 of the handle part 17 » in which the guide bore 16 extends are radial Passages 20 are arranged, in which locking bodies 21 designed as spheres are displaceably arranged.

In the position shown in Figure 1, the locking bodies 21 engage in a locking recess 18 and lock so the rod 15 opposite the handle part 17 by a sliding sleeve 22, which is supported by a closing spring 23 in its latching position shown in Figure 1 is held, the latching body 21 are in engagement with the latching recesses 18 held.

_{When the sliding sleeve 22 is brought into its c end} latching position against the force of the closing spring 23, the latching bodies 21 can evade radially outward from an enlarged recess 2k formed expansion. In this position, the rod 15 can be moved axially with respect to the handle part 17.

The diameter of the recess 2k is larger than a foot part 25 of the hollow body 8 that protrudes from the end face 13 ^, apart from a small amount of movement.

As Figure 1 shows, the sliding sleeve 22 is in an annular groove-like space 26 of the handle part, on the Bottom the closing spring 23 is supported, out. The space 26 is the one facing the handheld power tool The end of the handle part 17 is arranged behind a protective plate 27 molded onto the handle part 17. For better Guide and support carries the rod 15 on its

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rem of the threaded sleeve 1 k applied a guide ring 28 here pressed on. The outer diameter of the guide ring 28 is slightly smaller than the diameter of a cylindrical bore 29 extending in the handle part 17. The rod 15 can consist of an aluminum alloy or steel.

Of course, the locking recesses 18 can also be produced in a different way: FIG. 3 shows as a groove-shaped locking recesses 38 extending over a side surface of the hexagonal profile of the rod 15 and FIGS. K and 5 pyramid-shaped depressions U8, e.g. Of course, the locking recesses can also be formed by conical, drilled depressions (Figure k) .

Claims (8)

R. 18035 8/27/1982 Vo / Wl ROBERT BOSCH GMBH, 7000 Stuttgart 1 claims 1. Additional handle for attachment to a hand tool, s machine, with a tensioning band that is placed around a particularly cylindrical, "preferably containing the tool spindle extension of the housing of the hand machine tool, the ends of the tensioning band arranged over two on one end face of a hollow body , deflection shoulders running parallel to the axis of the extension are guided and attached to a tension screw which is arranged in the interior of the hollow body essentially parallel to its longitudinal axis and is screwed into a threaded sleeve which is also supported on the front side on the end face of the hollow body facing away from the deflection shoulders, characterized in that that the threaded sleeve (1 k ) is integrally formed on a rod (15) with a polygonal cross-section, in particular a hexagonal cross-section, which is longitudinally displaceable in an associated central guide bore (16) of a handle part (17) which is preferably made of plastic is performed and Has latching recesses (18, 38, U8) into which latching bodies (21), preferably balls, arranged displaceably in radial passages (20) of the handle part (17) engage. 2. Additional handle according to claim 1, characterized in that that the locking body (21) in extensions (2U) of a sliding sleeve (22) which in its locking position the ρ Φ r »* - β r · t * t» ■ tat · · t -tt · · ι ι · # · · * ■ · # · ι - 2 - R. 18035 Mouths of the passages (20) closes, can move radially outward when the sliding sleeve (22) after Axial displacement against the force of a closing spring (23) is brought into its final position. 3. Additional handle according to claim 2, characterized in that that the sliding sleeve (22) is arranged in an annular groove-like space (26) of the handle part (17), at "'..essen The bottom of the closing spring (23) is supported. k. Additional handle according to claim 2 or 3, characterized in that the sliding sleeve (22) is guided with its bore on a cylindrical extension (19) of the handle part in which the passages (20) are arranged, the enlargement being provided by an enlarged recess ( 2U) is formed, the diameter of which slides on a cylindrical foot part (25) of the hollow body (8). 5. Additional handle according to one of the preceding claims, characterized in that the sliding sleeve (22) is arranged lying on the end of the handle part (17) facing the hand machine tool behind a protective plate (27) formed on the handle part (17). 6. Additional handle according to one of the preceding claims, characterized in that the latching recesses (18, 38) as extending at least over a side surface of the Rod (15) with a polygonal cross-section extending groove-shaped Recesses (18, 38) are formed. 7 · Additional handle according to one of claims 1 to 5, characterized characterized in that the locking recesses (U8) as conical or pyramidal depressions in the rod (15) are formed. - 3 - R. ¹⁸ ° 35 8. Additional handle according to one of the preceding claims, characterized in that the rod (15) at its end facing away from the threaded sleeve (1U) has an in particular pressed-on guide ring (28) is provided with a cylindrical outer surface, the outer diameter of which in a cylindrical bore (29) of the handle part (17) out i st.