EP3416779B1 - Angle grinder dust hood - Google Patents

Description

"Angle grinder dust hood"

The present invention relates to an angle grinder dust hood with a hood body for covering a circular grinding wheel and with a sealing element extending along a circumference of the hood body for at least partially sealing the hood body with respect to a surface to be machined by the grinding wheel. The angle grinder dust hood has a suction connection, via which a surface removal can be sucked out of the hood body. The sealing element may be, for example, a brush curtain, slats or the like. Moreover, it is also possible that the sealing element is a single single elastic element or several individual elastic elements. The elastic member may be a foam, an elastomer (e.g., rubber, rubber, etc.) or the like.

Angle grinder dust hoods of the type mentioned are basically known from the prior art. They are used to prevent dust spreading during grinding work to protect the health of a user of the angle grinder. It is known to provide the hood body with a sealing element, for example a circumferential brush curtain or with a plurality of brushes, so that the hood body terminates on the surface to be machined of a workpiece. If the angle grinder is placed slightly obliquely on the surface of the workpiece to be machined, then the sealing element can compensate a gap which may arise between the hood body and the surface of the workpiece to be machined.

In the WO2008 / 033377 A2 , which forms the basis for the preamble of claim 1, a grinding tool is disclosed. The grinding tool comprises a handle assembly having a support member and a head assembly including a grinding member that is rotatable relative to the handle assembly about a drive axis. The grinding tool also includes a pivot assembly that pivotally couples the head assembly to the support member of the handle assembly. The support member pivotally supports the pivot assembly, the drive axle extends through the pivot assembly, and the head assembly is pivotable about a plurality of different axes relative to the support member.

From the EP 2 202 029 A2 a tool holding head for a hand-held cleaning / grinding machine is known, comprising a plate device which is fixed or fixable on the cleaning / grinding machine, and a tool receiving device to which a tool for surface processing is fixed or fixable and which relative to the plate means about an axis of rotation is rotatable, wherein on the plate means a bearing device is elastically mounted on a processing surface, wherein the abutment means surrounds the tool receiving device.

It is an object of the present invention to provide an angle grinder dust hood, which prevents axial falling out of the sealing element from the hood body and / or the hood segment.

The object is achieved with an angle grinder dust hood with a hood body for covering a circular grinding wheel and with a sealing element extending along a circumference of the hood body for at least partially sealing the hood body with respect to a surface to be machined by means of the grinding wheel, and with a suction connection via a surface removal the hood body can be sucked off, wherein the sealing element in the hood body in the axial direction, based on the axis of rotation of the grinding wheel, is spring-mounted by at least one spring element, and wherein the spring element has a base bar via which the spring element is attached to the hood body, achieved in that the Spring element has at least one retaining bracket, which is adapted to prevent an axial falling out of the sealing member from the hood body, wherein the headband protrudes in the axial direction of the base web and at its other end an axial stop for a retaining rail of the sealing element is formed.

It has proved to be essential for the invention, when the spring element has a base web. About the base bar, the spring element is attached to the hood body.

The invention includes the recognition that, in particular in an overhead operation of an angle grinder, a hood body with according to the prior art rigidly attached thereto brush curtain is pulled by gravity and a possibly connected to the suction suction hose down. Thus, disadvantageously, a gap between the brush curtain and the surface to be processed arise. By the invention according to the invention feathered in hood body brush curtain of the brush curtain is always pressed to the machined surface, whereby a gap is avoided or at least substantially reduced.

The invention also includes the recognition that a worn brush curtain may typically have a high stiffness with respect to the axial direction, so that a lot of force has to be expended to expose the grinding wheel against the stiffness of the worn brush curtain on the surface to be machined To bring workpiece. This is because with angle grinder dust hoods of the prior art, as already mentioned, the brush curtain is rigidly attached to the hood body.

In addition, the present invention includes the knowledge that an already heavily worn pad, in particular a diamond pot, is used in conjunction with a new angle grinder dust hood and the user disadvantageously against the relatively high stiffness of the still stiff brush curtain the new angle grinder dust hood already flattened sanding pad must press on the surface to be machined of the workpiece. A worn pad often has a lower height, i. a less concave shape than a new or unused sanding pad.

In the angle grinder dust hood according to the invention, the spring element takes over the axial movement of the sealing element with respect to the hood body. Any radial displacements can continue to be compensated by the sealing element itself. In the context of the invention is intended to be understood by a spring element is a preferably discrete spring element and not merely a possible spring action or resilience of the brush curtain in the axial direction.

In addition, the invention includes the recognition that angle grinder dust hoods of the prior art to achieve the spring action of the invention can not be developed such that a spring element is provided approximately between hood body and angle grinder housing. This would have in overhead work the disadvantage that the weight of a suction hose connected to the suction would compress such a spring in an undesirable manner.

In a particularly preferred embodiment, the hood body is designed to cover a major part of the grinding wheel. The angle grinder dust hood can have a hood segment which can be displaced in the circumferential direction of the hood body along the hood body and which is provided for, as required, gradually covering and leaving free a remaining part of the grinding wheel. This allows a near-wall grinding operation by means of the remaining part of the grinding wheel, which is not covered by the hood body. Preferably, in the hood segment also a sealing element in the axial Direction, based on the axis of rotation of the grinding wheel, spring-loaded by at least one spring element.

It has proven to be advantageous if the spring element has a preferably flat base web. About the base bar, the spring element may be attached to the hood body and / or the hood segment. Preferably, fastening takes place by means of a pin, a screw and / or a rivet. In addition, it can also be provided that the spring element is mounted directly in the hood body by means of a spring clip via an undercut. The spring clip can also be referred to as a clip, so that the spring element is clipped into the hood body. Furthermore, the spring element can also be injected directly into the hood body or into the hood housing. In the base web preferably at least one hole is provided, into which a pin, a screw or a rivet can engage.

Alternatively, it could also be provided that the spring element is attached to the first and / or second retaining rail for the sealing element.

Preferably, the spring element or the spring elements are arranged within a volume defined by the hood body or hood segment. Preferably, the hood body and / or the hood segment has a housing section whose curvature corresponds to the curvature of the grinding wheel. Preferably, the spring element is arranged in the immediate vicinity of this section. Preferably, the spring element is arranged as far as possible from a rotation axis of the grinding wheel within the hood body volume or the hood segment volume.

It has proved to be advantageous if the spring element has at least one spring rocker protruding from the base web. Preferably, the spring element is mounted such that the orientation of the projecting spring wings preferably corresponds approximately to the outer periphery of the hood body.

According to a further embodiment, it could also be provided that the spring element is also arranged radially.

Alternatively, it can also be provided that the spring element has two spring wings projecting from the base web. In this way, a higher stability of the spring element in an assembled state and an increased spring force can be achieved.

When the spring element is mounted, the spring wings form a tangent to the circular grinding wheel or to the oval body of the grinding hood.

Preferably, the headband in the radial direction, based on the axis of rotation of the grinding wheel, for the purpose of replacing the brush curtain deflected. Further advantageously, the axial stop may be formed as a stop web, which preferably extends parallel to the base web. Advantageously, the stop formed as an axial stop has a recess, so that a contact surface between the stop web and the running as a brush curtain sealing element or the holding rail of the brush curtain is reduced. The recess preferably requires a saving of material and a low surface for dust. In addition, a friction surface is reduced with respect to the brush curtain, so that it can be moved easily in the axial direction.

Alternatively, that the headband can protrude in the axial direction of the base web, the headband may be formed as a clamping sleeve, which is arranged on a side facing away from the base web of a respective spring rocker. Preferably, the clamping sleeve is designed for clamping a retaining rail of the brush curtain. In other words, the clamping sleeve, which holds the brush curtain, even sprung.

It has proved to be advantageous if the spring element is formed in one piece, preferably made of spring steel. Particularly preferably, the spring element in the axial direction on a spring stiffness, which is less than a stiffness of the brush curtain covered brushes. Alternatively, the spring element can also be designed in several parts.

Particularly preferably, a plurality of spring elements along the circumference of the hood body and / or the hood segment is provided. It has proven to be advantageous if an angle grinder dust hood, which has a hood body and a hood segment, is provided with five preferably evenly spaced spring elements.

In a further preferred embodiment, the hood body has a central opening through which a drive spindle, to which the circular grinding wheel is to be attached for grinding operation, can project through the central opening. At the central opening, a groove is preferably formed, so that the hood body can be fixed positively and thus fixed to the frame on an angle grinder.

The object is also achieved by an angle grinder with an angle grinder dust hood of the type described above, wherein the hood body is fixed to the frame arranged on the angle grinder.

Further advantages will become apparent from the following description of the figures. In the figures, various embodiments of the present invention are shown. The figures, the Description and claims contain numerous features in combination. The skilled person will conveniently consider the features individually and summarize meaningful further combinations.

In the figures, identical and similar components are numbered with the same reference numerals.

Fig. 1

eine schematische Unteransicht einer erfindungsgemäßen Winkelschleifer-Staubhaube mit einem Federelement gemäß einer ersten Alternative;

Fig. 2

eine Schnittdarstellung des Ausführungsbeispiels aus Fig. 1;

Fig. 3

ein Federelement gemäß einer zweiten Alternative;

Fig. 4

das Federelement aus Fig. 3 in Seitenansicht.

Show it:

Fig. 1

a schematic bottom view of an angle grinder dust hood according to the invention with a spring element according to a first alternative;

Fig. 2

a sectional view of the embodiment of Fig. 1 ;

Fig. 3

a spring element according to a second alternative;

Fig. 4

the spring element Fig. 3 in side view.

EXAMPLES

An inventive angle grinder dust hood 100 is in Fig. 1 shown in bottom view. The angle grinder dust hood 100 has a hood body 10 for covering a circular grinding wheel, not shown here. An axis of rotation R of the grinding wheel is indicated by a dot-dash line. The angle grinder dust hood 100 also has a hood segment 20 which is displaceable along a circumferential direction U of the hood body 10 along the hood body 10.

The hood body 10 is configured to cover a majority of the grinding wheel, with the sliding hood segment 20 being provided for covering and releasing a remaining portion of the grinding wheel.

Both the hood body 10 and the sliding hood segment 20 have a sealing element 30 in the form of a brush curtain. Since the angle grinder dust cover 100 of Fig. 1 has both a hood body 10 and a hood segment 20, the brush curtain 30 is formed in two parts or two brush curtains are provided. The brush curtains 30 serve to seal the hood body 10 and the hood segment 20 to a surface to be machined, which is not shown here. A surface removal in the course of processing can be sucked off via a suction connection 40 provided on the hood body 10.

According to the invention, the brush curtain 30 is spring-loaded with respect to the hood body 10 and the hood segment 20 in the axial direction, relative to the axis of rotation R of the grinding wheel, by a spring element 50. The spring element 50 is on the left side of Fig. 1 shown isolated.

The spring element 50 has a flat base web 51, via which the spring element 50 is fastened to the hood body or hood segment 20. Im in Fig. 1 illustrated embodiment, the spring element 50 via a pin 52 (see. Fig. 2 ) (eg heat staked), the pin engaging a hole 52 '.

The spring element 50 has two projecting from the base web 51 in opposite directions spring wings 53. The spring wings 53 exert a spring action on a retaining rail 31 of the brush curtain 30. The spring wings 53 are oriented with mounted spring element 50 in the direction of the outer circumference U of the hood body 10.

The spring element 50 has a retaining clip 55, which is designed to prevent an axial falling out of the brush curtain 30 from the hood body 10 or the hood segment 20. Im in Fig. 1 illustrated embodiment, the headband 55 protrudes in the axial Direction from the base bar 51 and has at its other end a stop for the retaining rail 31 of the brush curtain. The axial stop is presently designed as a stop web 57 which extends parallel to the base web 51 and has a recess 59.

The retaining bracket 55 is deflectable in the radial direction, indicated by the double arrow, for the purpose of replacing the brush curtain. Thus, advantageously, the brush curtain 30 can be replaced without a tool is required.

How out Fig. 1 it is apparent that a functional integration is realized by the spring element 50, namely on the one hand, the spring action according to the invention in the axial direction, on the other hand falling out of the brush curtain from the hood body 10 and the hood segment 20 is prevented.

Again Fig. 1 can be removed, the hood body 10 has a central opening 11, through which a drive spindle, not shown here, to which the circular grinding wheel is to be attached, can protrude through the central opening 11. At the central opening a groove 12 is formed, so that the hood body 10 can be fixed positively and thus fixed to a frame on an angle grinder.

Fig. 2 now shows a sectional view of the embodiment of the angle grinder dust hood 100 Fig. 1 ,

It can be clearly seen that the spring elements 50 arranged within a volume of the hood body 10 on the outer edge of the hood body 10 exert a spring action on the retaining rail 31 of the brush curtain 30 through their respective spring wings 53. At the same time, the respective stop webs 57 form an axial stop for the retaining rail 31, so that it is securely held within the hood body 10.

Fig. 3 shows a spring element 50 'according to a second alternative. The retaining clip 55 is designed as a clamping sleeve which is arranged on a side facing away from the base web 51 of a respective spring rocker 53. Designed as a clamping sleeve retaining bracket 55 are used to clamp the retaining rail 31 of the brush curtain 30 (see. Fig. 4 ).

This in Fig. 3 shown spring element 50 is particularly suitable for, relative to the radial direction, comparatively narrow support rails. Advantageously, the fact that the retaining bracket 55 are formed as clamping sleeves, any manufacturing tolerances of the retaining rail are well compensated.

Fig. 4 finally shows the spring element of Fig. 3 in side view, wherein above the holding clip 55 designed as a clamping sleeve, a brush curtain 30 with holding rail 31 is shown, which is in the concept (indicated by the arrow), to be clamped in the clamp designed as a clamping bracket 55.

At the base web 51 of the spring element 50 of Fig. 3 two holes 52, 52 'are provided to secure the element 50 in the same way as in FIG Fig. 1 and 2 by then two pins 52 on the hood body 10 and the hood segment 20 to fix.

LIST OF REFERENCE NUMBERS

10

hood body

11

Central opening

12

groove

20

cap segment

30

sealing

31

retaining rail

40

suction

50

spring element

51

base web

52

Pin code

52 '

hole

53

swing arm

55

headband

57

stop web

59

recess

100

Angle-dust cap

R

axis of rotation

U

Circumference / circumferential direction

Claims (12)

1. Angle grinder dust hood (100) with a hood body (10) for covering a circular grinding wheel and with a sealing element (30) running along a circumference (U) of the hood body (10) for sealing the hood body (10) at least in sections with respect to a surface to be worked by means of the grinding wheel, and with a suction connection (40), through which material removed from the surface may be sucked out of the hood body (10), in which the sealing element (30) is spring loaded through at least a spring element (50) in the axial direction with reference to the axis of rotation (R) of the grinding wheel in the hood body (10), and in which the spring element (50) has a base bar (51), through which the spring element (50) is fastened to the hood body (10),
   characterised in that the spring element (50) has at least a retaining clip (55), which is made to prevent the sealing element (30) from falling out of the hood body (10) axially, in which the retaining clip (55) projects in an axial direction from the base bar (51) and an axial stop (57) is made at its other end for a holding rail (31) of the sealing element (30).
2. Angle grinder dust hood (100) according to claim 1,
   characterised in that the hood body (10) is made for covering a predominant part of the grinding wheel and the angle grinder dust hood (100) has a hood segment (20) that may be moved along the hood body (10) in the circumferential direction (U) of the hood body (10), which is provided for gradually covering and uncovering a remaining part of the grinding wheel, if necessary, and in which a sealing element (30) is also spring loaded through at least a spring element (50) in an axial direction with reference to the axis of rotation of the grinding wheel in the hood segment (20).
3. Angle grinder dust hood (100) according to claim 1 or 2,
   characterised in that the base bar (51) of the spring element (50) is made flat, in which the spring element (50) is fastened to the hood body (10) and/or the hood segment (20) through the base bar (51), preferably by means of a pin (52), a screw or a rivet.
4. Angle grinder dust hood (100) according to claim 3,
   characterised in that the spring element (50) has at least a spring pendulum (53) projecting from the base bar (51), in which the orientation preferably corresponds to the outer circumference (U) of the hood body (10).
5. Angle grinder dust hood (100) according to one of claims 1 to 4,
   characterised in that the retaining clip (55) may be deflected in a radial direction with reference to the axis of rotation (R) of the grinding wheel for the purpose of changing the sealing element (30).
6. Angle grinder dust hood (100) according to claim 5,
   characterised in that the axial stop (57) is made as a stop bar, which runs parallel to the base bar (51) and preferably has a recess (59), so that a contact surface between the stop bar (57) and the sealing element, which is made as a bristle curtain (30), is reduced.
7. Angle grinder dust hood (100) according to one of claims 1 to 4,
   characterised in that the retaining clip (55) is made as a clamping sleeve, which is arranged on a side of a respective spring pendulum (53) facing away from the base bar (51) and is made for clamping a holding rail (31) of the sealing element (30).
8. Angle grinder dust hood (100) according to one of the previous claims,
   characterised in that the spring element (50) is made in one piece, preferably from spring steel.
9. Angle grinder dust hood (100) according to one of the previous claims,
   characterised in that the spring element (50) has a spring stiffness in an axial direction that is smaller than a stiffness of the bristles of the sealing element, which is made as a bristle curtain (30).
10. Angle grinder dust hood (100) according to one of the previous claims,
    characterised in that a multiplicity of spring elements (50) are provided along the circumference of the hood body (10) and/or the hood segment (20).
11. Angle grinder dust hood (100) according to one of the previous claims,
    characterised in that the hood body (10) has a central opening (11), through which a drive spindle, on which the circular grinding wheel is to be set, may project, in which a groove (12) is made on the central opening (11), so that the hood body (10) may be fastened in a form-fitting way and therefore fixed to the frame on an angle grinder.
12. Angle grinder with an angle grinder dust hood (100) according to one of the previous claims, in which the hood body (10) is arranged fixed to the frame on the angle grinder.

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