DE4004463A1 - Switching device for range of modular electric hand tools - has internal of external manually controlled ring for operating interior switch plate and brush angle for reversing motor - Google Patents

Abstract

A manually operated switching device in the form of a totatable ring (20) is positioned concentricall w.r.t. to the axis of a cylindrically housed power tool in the region of the non drive end motor bearing. The ring (20) may be outside the casing (ii) of the tool or inside with exteride access and is arranged to engage with an interior rotable switch plate for motor on/off or reversal. The ring (20) is spring loaded to a rest position by springs (31a) but cn be locked in an operating condition by a spring catch (3A) set in the periphery of the ring (20). The catch (34) triggers a return to the rest position of the ring (20) when the tool is laid down. USE/ADVANTAGE - Range of matched power tools e.g. drills, grinders etc. converient. easily manipulated means of motor control and can easily be arranged to set brush orientation for correct comution forward and reverse. Assists unification of control for a wide range of standardized flower tools employing appropriate switch plates for min internal wiring.

Description

State of the art

The invention is based on a switching device according to the preamble of claim 1.

It is common practice to use power tools, specifically Electric hand tools, for example with the help of Toggle switches, for example with a rocker-like structure, or switch on and off by slide switch, whereby these switches in a suitable manner on the outside of the housing are attached or only their operating parts protrude through housing openings and ver can be put. With many handheld electrical devices, for example in drilling machines, rotary hammers and the like. it is also common in connection with the input and  Turn off at the same time to adjust the speed len by a pistol grip like a finger spanned slide switch at its initial Movement turns the power tool on and one further free distance in the switch adjustment serves to ver a potentiometer, for example which, for example, part of a phase can be cut circuit, through which then the Speed of the electric hand tool driving Electric motor are run up to the stop can.

It is also the case with many electric hand tools usual to reverse the direction of rotation, for example for screwdrivers to screw both on and off to be able to turn it off. This usually happens also by simple electrical switching the power supply to the stator and / or to the brushes, which, however, is not the case with regard to efficiency is optimal, since in the latter case a simultaneous mechanical / geometric brush adjustment by pre given angular amounts is displayed. Besides this external wiring it is with electric hand tools also known (DE-OS 36 06 926), this in electri circuit area on the basis of to build electrical plug components so that the wiring effort is reduced and a lot number of conductive parts, also for the direction of rotation reverse or to effect the on / off process takes the form of current-carrying webs that correspond to appropriate plastic parts, including the housing, if necessary, in the manufacture of the same  are injected. In this known electric hand tool in the form of a hand drill (DE-OS 36 06 926) are related to the electrical circuit area Elements and lines in the form of one another pluggable block modules.

In general, it is also the case with electric hand tools known (DE-PS 33 11 557), at one end of the stator an electric motor for a hand tool to arrange similar holding part, which also as Motor bridge can be called. This motor bridge is for positioning and storing the on this Way held rolling bearing for the armature shaft be true and can be used for example Connect neter way with the stator that end and running towards the stator on the Motor bridge pins are arranged which are plugged on the motor bridge on the stator to achieve a enable precise alignment. This gives at the same time through the opening in the motor bridge for the assigned armature shaft Rolling bearing the end position determining the air gap.

The invention is based, the elek trical switching, for example the on / Switch-off process or a reversal of the direction of rotation a power tool, especially an electrical craft simplify stuff for at least one of the order switching operations drastically reduce the wiring effort to reduce by directly in the engine Ver wiring or in the adjustment options there is intervened.  

Advantages of the invention

The power tool according to the invention solves this problem with the characterizing features of claim 1 and has the advantage that a clearly operable Setting device for at least one of the electrical Switching options for an electric hand tool with which, for example, the on / off switching process and / or a reversal of direction of rotation there can be realized by mecha from the outside nisch immediately and without additional electrical Wire connections directly into a control area on the electric motor driving the electric hand tool intervenes.

Therefore, one available for the realization Invention of suitable electric motor internal switching or control elements, preferably an inner switch ring, due to its limited rotational movement electrical switching in the area of the drive mo tors can be made. It works for this purpose the switching ring in a suitable manner with directly on Electric motor-mounted conduits, preferred together in a suitable lead frame, so that in the processed form of the punching die ters, for example, by the inner shift ring movement the electric motor can be switched on and off can or the optimal reversal of rotation with the same timely brush adjustment can be made.

The present invention is only apparent a putative disadvantage in buying that in it  is that the heart of every electric hand tool, namely the electric drive motor one in itself completely complete, all necessary Bearings for the rotor shaft and their flawless Centering as well as for the other engine parts having drive unit with corresponding Encapsulation including the switching ring mentioned is. Here, an electri can also be used with advantage universal motor as used in the German utility model G 89 08 645.5, the Priority is claimed, or DE-OS 39 23 421 be is written. It is therefore also below Reference to this available description of one detailed explanation of this electrical Universal motor here apart, although it ver stands that everyone else, a switching ring in suitable ter training electric drive motor likewise for the realization of the present invention suitable is.

The invention can then be used with particular advantage insert if the housing itself consists of several however in the general axial direction of the electro hand tool divided areas, wherein a main housing part a cylindrical, closed has tubular structure, as is the case with spe specifically trained professional tools is already known in which the drive unit then just shot up to a seat stop need to be. Such a main body from cylindrical basic structure offers a special suitable seat for the arrangement of an inner position rings or a possibly also open ring structure, which is inside the Ge housing is best guided and only partially visible is, or an external position  rings, which can then also be of circular shape and surrounds the housing tube shape as a closed ring and wherein both collar shapes with a positive fit with radial projections inside reach for the switching ring and this with its own manual Ver take position.

By dividing the housing into the main housing seteil and an axially attachable cover you also create in the transition between these two Housing parts an area where the outer collar easily applied and against shifting can be held by the rear cover.

The construction of such an electric hand tool can then be taken in such a way that it is self-contained Sene rigid, self-supporting unit of the Elektroan drive motor on the output side, i.e. where the motor shaft end piece, either itself as a gear trained or carrying a pinion, the drive A-side shield protrudes on this side, the gearbox be of the respective electric hand tool, i.e. at for example the angle head for an angle grinder or the gear head of a hand drill is flanged; then the electric drive motor inserted into the tubular main housing; the connection with this takes place via bores from the gear head, so that the structure, so to speak is made from behind and the electric motor only on the side facing away from the gearbox, preferably flexible with a bearing shield protrusion in a housing recess for safety Ren bracket also engages on this side.

Then you can on the back open  Slide on the collar until it stops ben who with the electrical switching connections the engine. The structure is completed then through the rear housing cover, which with its front annular edge into one this edge edge receiving annular groove in the collar intervenes and even on a rear-facing tapered protrusion of the main body strikes and there also screwed or otherwise befe can be increased. In this way, the Keep the collar in place without any problems, because to the rear it is through the engaging ring edge of the rear housing cover part secured and after at the front can be secured against axial displacement in that the collar and main housing at this point with stepped, facing each other bear the directed ring grooves against the stop.

The collar then sits on the outside of the tubular, closed housing body and reaches with Inside directed through housing openings jump on the shift ring in the area of the B bearing shield of the drive motor on which it is out is aimed so that a switching ring adjustment for Reversing the direction of rotation or for on and off switching of the device is possible.

An advantageous embodiment of the present invention finally consists in the fact that when used the collar as an instrument for turning on and off switch the electric motor the collar one yourself active return through in a suitable manner  attacking feathers and so in the switched on th position can be locked, namely by an outer seesaw with a hook-like front jump into a recess in the main housing wall intervenes that when pushing back the rocker or putting it down the rocker in a suitable position triggers and the switching ring by its own spring pretension snaps back into the original position.

drawing

Embodiments of the invention are in the drawing and are shown in the following Description explained in more detail. Show it:

Fig. 1 as a partial section of a partial view of an electric drive motor accommodated in a tubular main housing (an angle grinder) with arrangement of the outer adjusting ring and its passage through the electric motor switching ring;

Figure 2 shows the tubular main housing of an electric hand tool, especially for an angle grinder, with a set collar.

Fig. 3 shows the representation of Fig. 2 in a view from the right, with the adjusting ring in its deflected position while the

Fig. 4 shows the same view with the collar in the rest position; the

Fig. 5 and 6 show detail views inner half of the dotted outline of Figures 3 and 4 of the Arretierwippe for the adjusting ring in the engaged position and in the rest position (Fig. 6). (Fig. 5);

Fig. 7 shows a better understanding of the overall construction of the electric hand tool (angle grinder as a possible embodiment) a top view of the representation of Fig. 1 from the right, from which the inner switching ring of the electric motor can be seen and the

Fig. 8 shows a possible embodiment of an electric hand tool with an outer adjusting ring.

Description of the embodiments

The basic idea of the present invention is outside or inside the housing of a power tool, specifically an electric hand tool, at the level of the B-end shield of the electric motor that drives this electric hand tool to arrange a rotatable collar, the Verdre in one direction or the other given angular positions and with projections inside, e.g. through correspondingly cut out housing openings up to the inner switching ring of the electromo tors engages so that it is possible to operate of the collar electrical switching in the area of the electric drive motor immediately before increase.

Before the invention is explained in detail, attention is drawn to the fact that a particular preferred embodiment of an electrical Drive source, namely a specially for the  Requirements of the present invention trained and final assembled, self-contained electri universal motor is fully described in DE-GM 89 08 646.5, whose priority is claimed here is so that in the following this drive motor single no matter how far, especially its outer shape forth is explained how this to understand the Invention is necessary. But it will be noticed sam made that the available description of this known drive motor expressly to the obvious The subject of the present invention written and referred to.

On the other hand, it goes without saying that for the Reali sation of the present invention also other universities Sal motors are suitable, provided they have a rotatable one Have switching ring, which makes electrical Switching over for the electric motor allowed. Further it is noted that the following detail Explanation especially on structure and on / off switch mechanism is aimed at an angle grinder, but it is understood that the inventions available electrical intervention options especially in the operation of the drive motor suitable and usable for such electric hand tools are in which a via the collar adjustment Reversal of the direction of rotation is made possible with the Angle grinders described here, however, are not necessary is.

The partial representation of FIG. 1 shows an electric universal motor 10 as a suitable drive source, which is located within a tubular main housing 11 and is of generally cylindrical shape. The B-end shield 12 is formed so that it forms a hub 13 for the B-bearing of the rotor shaft on this side, which is held in one piece by ribbed beidsei term carriers 14 a, 14 b. On an outward-facing outer ring surface (not visible) of the B-end shield, there is rotatably a switching ring which also carries the brushes 15 in quivers 16 and which is visible in the top view of FIG. 7 and designated 23 there. Against axial falling, the switching ring 23 is held by a locking ring 17 which is anchored on the B-end shield 12 with locking lugs 18 projecting inwards.

In order to be able to perform the rotary movement of the switching ring, which, as described in the already mentioned Ge usage pattern or the corresponding DE-OS 39 23 421, a reversal of the direction of rotation or the switching on / off of the electric motor is possible, axial projections 19 can be made on the switching ring a, 19 b may be provided, thereby lying with the outer or inner, the collar guided on the housing 20 come into operative connection that this has on both sides inwardly directed projections 21 a, 21 b which have the projections 19 a, 19 b of the switching ring so that it rotates when the outer adjusting ring 20 rotates. As a result, not only can the brushes be oriented in a new win cell position for the respective direction of rotation, but also, if desired, produce further electrical switches. If the collar is inside a hand-held machine, for example, and is then only partially visible, then these housing openings are used to manually actuate the collar from the outside, for example if an adjusting handle or sliding piece on the collar protrudes through the opening or is accessible through it.

Here are in any position per se, in the illustrated embodiment within the two-sided carrier 14 a, 14 b of the B-end shield 12, only two connecting plug contacts (in Fig. 4 at 22 a, 22 b recognizable), the two power supplies represent for the drive motor and are to be connected to an external power supply, for example by plug connection with an electrical plug-in module, which is designed so that further electrical switching operations can be carried out with this, if necessary for the specific electrical hand tool, such as the "gas function "on a hand drill or switching the electrical hand tool on and off when the influence of the outer collar is reserved for reversing the direction of rotation. This depends, as is understood, on the type of power tool and, of course, on the electrical wiring within the electric motor specified by the lead frame shape, with which the switching ring of the electric motor is in a corresponding contact connection or can be brought depending on the rotation.

Here, 1 is a better understanding in Fig., The tubular main body not shown led beyond the outer collar 20 in the plane of the drawing to the left for reasons. This can be seen in more detail in FIG. 2, while in FIG. 1 the B-side motor details can be better recognized. In the following, the conditions of an angle grinder will be dealt with specifically, so that here, always, but not restrictively, there is talk of an outer adjusting ring.

The sectional view of FIG. 1 shows how an annular shoulder 24 of the adjusting ring 20 formed by internal steps sits on the facing outer edge 25 of the main housing. Opposite the adjusting ring has an axially opening ring recess 26 , into which the front edge of a rear cover part housing 27 then engages to secure the adjusting ring ( FIG. 8), which is pushed onto an inner projection 28 of the main housing 11 as far as it will go. Before jump 28 is forked and includes an upper leg 28 a and a lower leg 28 b ( Fig. 2), the electrical switching module can be inserted into the space between these two legs, which is not the subject of the invention; a luster terminal 29 serves to relieve the strain on the supplied electrical line. For example, the lower leg 28 b of the main housing extension 28 can then serve to hold the rear housing cover 27 by means of a suitable screw, which is shown at 30 ( FIG. 8), against axial pulling-off, which at the same time also secures the adjusting ring 20 .

If the outer collar 20 for switching the device on and off, as is the case with the described angle grinder, then the switching ring also has an additional locking device with automatic reset, as shown in FIGS . 3, 4 and 2 . In this case, return springs 31 a, 31 b are initially provided which engage additional fastening pins 30 on the inwardly directed projections 21 a, 21 b of the adjusting ring 20 . The return springs are attached to the rear on housing-fixed webs 32 which, tapering conically, carry the rear bifurcated inner housing projection 28 of the main housing 11 .

Furthermore, the collar 20 is still a Arretieran arrangement 33 ; in the illustrated embodiment consisting of an approximately centrally mounted rocker 34 , which ends on one side in a bent locking lug 35 and the other side is biased by its own small preload compression spring 36 ( Fig. 5) so that the locking lug 35 after inside presses. It can be seen from the representation of FIGS. 3, 4 with 5 and 6 that when the outer adjusting ring is rotated in the counterclockwise direction according to the arrow A - with corresponding driving of the switching ring inside the engine via the projections 21 a, 21 b, when reached a predetermined position, the locking lance 35 is incident on a housing-fixed recess 37 and the outer adjustment ring 20 then also remains when released in this position. In the game concerning the angle grinder game, the device can be switched on and locked in the switched-on position as described, with the other end of the rocker corresponding to the arrow B in FIG. 3. If one then presses this rocker end to switch off the device, then the locking lug 35 is released again from the holding opening 37, the outer adjusting ring 20 snaps back into its original position and, due to the correspondingly strong force of the return springs, takes the switching ring in the region of the B- End shield of the drive motor with and switches off the device in this way, if necessary an automatic reset in a preferred direction of rotation can be realized if the direction of rotation is reversed.

Since the rear edge of the rocker switch 34 protrudes beyond the dimensions of the switching ring or housing in the switched-on position, it is sufficient, if positioned accordingly, that the device is simply put down, as a result of which the device's own weight pushes the rocker switch back and triggers the return movement of the adjusting ring becomes. The device then switches off.

In Fig. 7, finally, the bias springs 38 a, 38 b for the coals as well as separate receiving channels 39 a, 9 b can be seen, which can serve to accommodate chokes 40 for interference suppression of the drive motor and are also carried by the switching ring.

It can all in the description, the claims and the drawing features shown both individually or in any combination be essential to the invention with each other.

Claims (13)

1. Switching device for electrical switching (on / off; reversing the direction of rotation) of Elek trowerkzeugeen, especially electric hand tools such as hand drill, (angle) grinder, saw, jigsaw, hammer drill, hammer drill, polishing device u. Like., With a rotatable by predetermined Winkelbe sluggish switching ring ( 23 ) in the area of the B-end shield of the tool driving the electric motor, characterized in that outside or inside on the housing ( 11 ) of the power tool at the level of the inner switching ring ( 23 ) of the electric motor A manually rotatable ring structure (adjusting ring 20 ) is provided, from which at least one inwardly directed projection ( 21 a, 21 b) is guided to the switching ring ( 23 ) and connected to it, in such a way that an electrical switchover ( Switch on / off; reversal of direction) on the drive motor ( 10 ) via its switching ring ( 23 ). 2. Switching device according to claim 1, characterized in that the adjusting ring is arranged on the outside of the housing and is held by annular shoulders or ring projections in its axial position on the housing ( 11 ) of the power tool. 3. Switching device according to claim 1 or 2, characterized in that the adjusting ring ( 20 ) is held in an initial rest position by spring preload. 4. Switching device according to claim 3, characterized in that bias springs ( 31 a, 31 b) engage on the adjusting ring ( 20 ) which are attached to the rear of the housing ( 11 ) and whose restoring force is designed so that the adjusting ring ( 20 ) under Driving the inner switching ring ( 23 ) on the electric motor is returned to its starting position. 5. Switching device according to one or more of claims 1-4, characterized in that the inner switching ring ( 23 ) is electrically operatively connected to an electrically conductive lead frame shape forming the inner wiring of the electric motor, the lead frame shape being designed such that it depending on their line course turns the electric motor on or off or reverses in its direction of rotation. 6. Switching device according to one of claims 1-5, characterized in that a locking device ( 33 ) is provided on the adjusting ring ( 20 ) which locks the adjusting ring in its deflected or activated end position relative to the rest position. 7. Switching device according to claim 6, characterized in that the locking device ( 33 ) a on the adjusting ring ( 20 ) mounted rocker switch ( 34 ) to the spring-loaded with a nose ( 35 ) in the deflected state of the adjusting ring ( 20 ) in a Housing wall recess ( 37 ) engages and holds the adjusting ring ( 20 ) firmly in this position. 8. Switching device according to claim 7, characterized in that the rocker switch ( 33 ) is mounted approximately in the middle and in the activated state, in which chem the locking lug ( 35 ) in the housing recess ( 37 ) sits, with its opposite end, the approximate external dimensions of the housing protrudes in such a way that the locking position of the rocker switch is automatically released and the setting ring is returned to its starting position even when the electric hand tool is only put down. 9. Switching device according to one or more of claims 1-8, characterized in that the collar on an end housing ring edge ( 25 ) of a cylindrical or tubular main housing part ( 11 ) of the electric hand tool is set and in this position by a white rear housing cover part is held, the facing front edge of which engages in an axially opening ring recess ( 26 ) of the adjusting ring ( 20 ). 10. Switching device according to claim 9, characterized in that the adjusting ring ( 20 ) overlaps the main housing part with an apron-shaped ring projection ( 20 a). 11. Switching device according to one or more of claims 1-10, characterized in that the inner switching ring entraining, from the adjusting ring ( 20 ) outgoing projections ( 21 a, 21 b) axially ver running receiving openings for outgoing from the switching ring ( 23 ) of the electric motor Axial projections ( 19 a, 19 b) have such that the Mitnahmeposi tion between the collar ( 20 ) and switching ring ( 23 ) by axially sliding the collar ( 20 ) on the main housing ( 11 ) comprising the electric motor is possible. 12. Switching device according to claim 1, characterized in net that the collar on the inside of the housing (positive) is held and at least through a housing opening is accessible for manual adjustment. 13. Switching device according to claim 12, characterized in net that the inner collar with an actuation element protrudes through the housing opening.