EP1305137B1 - Hand-controlled grinding tool for machining round objects - Google Patents

Abstract

In a power grinder (1) with a motor (6) and a gear (7) that drive an oscillating drive means (2), which moves a grinding belt (3) secured to it to reciprocate, a simple change of the grinding belt (3) is made possible by providing that the grinding belt (3) has a hook-and-loop closure (4), or the grinding belt (3) is disposed with its first end (11) on the drive means (2), and its second end (12) is connected to a handle (13).

Description

State of the art

The invention is based on a hand-held grinding tool with an engine and a transmission, according to the preamble of claim 1 or claim 7. Such a tool is from DE 3 447 828 A or JP 11 320 374 A known.

For the machining of round objects in the built-in Condition, it is necessary that the abrasive belt is the radius of the object. In addition, the possibility must be to loosen or close the sanding belt. This is made by the devices available on the market by means of a Endlosschleifbandes achieved. So that the objects in the Built-in condition can be ground, this must be Cut abrasive tape and then glued again become. This is a very expensive method.

Furthermore, from DE 34 47 828 A1 a motor driven Grinding machine known for grinding, smoothing and polishing preferably round bars and tubes Use finds. This one uses an open, in one Loop around the workpiece looped abrasive belt, which with its two ends in two clamping or clamping devices of the grinding apparatus. A motor with rectified rotary motion drivable transmission sets via a movement device, the two clamping and clamping devices and thus also the sanding belt in an alternating, synchronously opposite movement that the Pulling sanding belt over the workpiece. This will be the Achieved grinding effect. Through such an oscillating movement Although a high level of operational reliability and a good Handling of the grinding apparatus allows, however, is the Expenditure to change the abrasive very large, since the Sanding belt with its ends from clamping or clamping device removed and the new sanding belt used again in this must become.

From DE 34 47 828 A a grinding hand tool machine is known, which with a oscillating drive means a with both ends attached thereto abrasive belt out and moved so that it forms a loop and releasable closure means to a can be looped to be sanded workpiece and this at least partially surrounds. As a result, cylindrical workpieces can be particularly effective outside be sanded. The handling of the Schteifhandwerkzeugmaschine is through relatively cumbersome to be solved closures of the abrasive belt less effective. In addition, the replacement / change of the sanding belt by its attachment to Drive means cumbersome and time consuming.

Advantages of the invention

An inventive hand-held grinding tool with the Features of claim 1 or claim 7 has the opposite the advantage that a simple change of the sanding belt is possible. By the closure according to the invention on the abrasive belt according to claim 1 enfalls a costly cutting and Gluing the sanding belt, or loosening and securing the Ends on a clamping or clamping device. The release, or Attaching the abrasive belt happens for example at a Velcro fastener by simple pressing without further Steps would be necessary. In addition, the Velcro closure provides sufficient high security against unintentional release.

A Possibility is the sanding belt, after which it around the was led around the object to be machined to the entire Drive means to lead around and the two ends of the Abrasive belt between drive means and to be processed Ge ' genstand by means of a hook and loop fastener directly to each other connect.

It is particularly advantageous if the drive means Oscillating head is, in particular, has the shape of a wheel. This makes it possible in a simple manner, the Guide grinding belt around the oscillating head and its two ends, as described above, between the oscillating head and the one to be machined To connect workpiece together.

Furthermore, it is advantageous if the transmission on his the Engine side facing away from a bevelled drive shaft has, on which eccentrically a pin is arranged, which is engaged with the drive means. This will be the given by the transmission drive movement, which is usually represents a rotation, converted into an oscillatory motion. This happens in a very easy to implement and structurally less expensive way. Especially preferred is doing, when the pin in a slotted guide on Drive means sitting.

Furthermore, it is preferred if the closure at the first end and formed at the second end of the abrasive belt. Across from an arrangement within the abrasive belt can thus the entire length of the abrasive belt to be exploited. This serves that with the same sanding belt round objects with can be processed very different diameters.

A further embodiment according to the invention according to claim 7 provides that the Abrasive belt arranged with its first end on the drive means is and its second end is connected to a handle. Also This allows a simple change of the sanding belt realize. In addition, it is characterized in a particularly simple way and possible, the abrasive belt around the object to be machined because not even the sanding belt of his attachment points must be solved.

It is advantageous if between the second end of the sanding belt and the handle is arranged an elastic element. As a result, the oscillating movement of the abrasive belt is not fully transferred to the handle and thus to the user's hand.

Furthermore, it is advantageous if the first end of the abrasive belt is rotatably mounted on the drive means. That's it possible that when unfavorable to reach places that edited the user should not be unnatural hand and Must take arm positions.

It is furthermore advantageous if the drive means is a machine insert is. This makes the grinding tool universal can be used, as well as other uses than the abrasive belt to the Machine insert can be coupled.

Further advantageous embodiments of the invention are the subject the dependent claims.

drawings

Embodiments of the invention are in the following Description based on the corresponding drawing closer explained.

Fig. 1

ein erstes Ausführungsbeispiel eines handgeführten Schleifwerkzeugs mit einem Klettverschluss,

Fig. 2

einen schematischen Ausschnitt aus Figur 1 ohne Schleifband und

Fig. 3

ein drittes Ausführungsbeispiel eines Schleifwerkzeugs mit einem Griff am Ende des Schleifbandes.

Show it:

Fig. 1

A first embodiment of a hand-held grinding tool with a Velcro fastener,

Fig. 2

a schematic section of Figure 1 without abrasive belt and

Fig. 3

a third embodiment of a grinding tool with a handle at the end of the abrasive belt.

In Figure 1, a hand-held grinding tool 1 is shown, the one Drive means 2 in the form of a vibrating head 5 has. The drive of the Schwangkopfes 5 by the in FIG. 2 described means. The oscillating head 5 is put in an oscillating motion. He swings around an axis 16. To the oscillating head 5, a grinding belt 3 is guided. The abrasive belt 3 has a closure 4, through which the first End 11 with the second end 12 of the abrasive belt 3 releasably to a Ring is connected. Hereinafter, as the shutter 4 exemplified a Velcro 4 described. The Velcro 4 is arranged so that he between the oscillating head 5 and a to be machined Subject matter lies. This will be a very simple one Changing the sanding belt 3 ensures. It is only necessary that both ends 11, 12, which by the Velcro 4 mi. in each other in Engage, disengage from each other. Besides, it is at this Embodiment possible, the grinding surface of the grinding belt 3, which is pictured on its inside when in the area of the worn out article, so to twist that an unconsumed piece of the abrasive belt 3 to be processed Subject matter is present. As a result, the abrasive belt 3 can be used longer will be saved and thus costs for the user. To the hand-held grinding tool 1 in its machining position To bring the Velcro 4 of the abrasive belt 3 is opened. Subsequently, the sanding belt 3 is about the object to be processed laid around and the Velcro 4 closed again. With Such a grinding tool 1, the operator is lightning fast in the Able to start working on the object. As well fast is a change of a worn abrasive belt 3 before yourself.

The oscillating head 5 is moved by a gear 7, which in a housing 18 of the grinding tool 1 is mounted and by a motor. 6 is driven. The drive is not essential to the invention ' Lich, so waived a closer execution of these elements becomes. At the end of the transmission 7, a drive shaft 8 is formed, which rotates about a longitudinal axis A of the grinding tool 1. The rotation the drive shaft 8 is arranged eccentrically by a at her Pin 9, which engages in a slotted guide 10 on the oscillating head 5, in an oscillating motion about a deflection angle D converted along the double arrow C. This happens because of that the pin 9 eccentric to the longitudinal axis A along a pin axis B is arranged. The closer embodiment is shown in Fig. 2. Front side, the drive shaft 8 by a against the Longitudinal axis A tilted end surface 20 limited. On this finishing surface 20 is arranged eccentrically to the longitudinal axis A of the pin 9. The pin axis B formed by the pin 9 extends in its extension by the axis 16 about which the oscillating head 5 oscillates. Due to the distance between pin axis B and longitudinal axis A. along the end surface 20 of the deflection angle D is defined. The value of the deflection angle D corresponds to the amplitude, in the case of the oscillation of the oscillating head 5 about the axis 16 along the double arrow C (Figure 1). The pin 9 is rotatably supported by a bearing 19 in the slide guide 10. In Fig. 2 was due to the clarity of the presentation of the sanding belt 3 is omitted.

The grinding area on the object is the area that faces away from the grinding tool 1. The sanding belt 3 is due to the oscillating movement of the oscillating head fifth moved back and forth over the grinding area, making it a Abrading the surface of the object in the grinding area comes.

In Figure 3 is a third embodiment of an inventive hand-held grinding tool 1 shown. Again, here are identical, or equivalent parts with the same reference numerals. The first end 11 of the sanding belt 3 is rotatable on the drive means 2 attached. The drive means 2 is on a machine insert 15 trained. At the second end 12 of the sanding belt 3 a handle 13 is attached via an elastic element 14. Hereinafter is described as an elastic element 14, a spring 14. Likewise, any other elastic elements 14 may be used. To use such a grinding tool 1 an object (not shown), the handle 13 becomes the object guided around, so that the sanding belt 3 at the grinding area (not shown) under tension of the spring 14 is applied. Due to the oscillating movement of the drive means 2 finds a Grinding movement in the grinding area, as described above, instead. By the spring 14, the oscillatory motion, which is the sanding belt 3 performs and transfers to the handle 13, greatly reduced, so that the operator can easily hold the handle 13.

An advantage of this embodiment is that the abrasive belt 3 does not have to be solved by the grinding tool 1. Thus, one is ensures fast processing of the object. Besides that is it is possible, the abrasive belt 3 over a wide range of its length to use, depending on which area you use the handle 13 applies the sanding belt 3 around the article. This can the abrasive belt 3 can be used longer without being replaced must become. This saves costs for the user. This Effect is enhanced when the sanding belt 3 on both sides is designed as a grinding surface. By the rotatable storage the first end 11 on the drive means 2 can thus also the in Fig. 3 outwardly facing surface of the grinding belt 3 for grinding be used round objects. The possibility of that To rotate grinding belt 3 relative to the drive means 2 brings Furthermore, the advantage that the user of hard to reach Make an object to be sanded not unnatural Hand or Armhaltung must take. This is the ease of use of the device increased enormously.

For example, the following objects can be used as abrasive belt 3 for all two exemplary embodiments:
An abrasive cloth belt, abrasive fleece, polishing belt, saw wire, brush belt or eraser belt.
In addition to the use of a hook and loop fastener 4 on the sanding belt 3, it is equally possible to use push buttons, clamps, screws, hooks or similar fasteners.
This results in a very widespread field of application. With a grinding tool 1 according to the invention, for example, the following objects can be processed:
A railing, in particular banisters, a garden fence with round or semicircular profile, turned table and chair legs, water pipes, heating pipes, downpipes of a gutter, posts, street lamps, traffic lights, bicycle and motorcycle frames.
Furthermore, the following operations can be carried out: rounding of edges of furniture, machining of small parts by means of stationary grinding and polishing equipment, erasing, removing adhesive residue, sawing of circular cutouts and sawing of pipes with saw wire.

LIST OF REFERENCE NUMBERS

1

Hand-guided grinding tool

2

drive means

3

sanding belt

4

Closure, in particular Velcro

5

Schwingkopf

6

engine

7

transmission

8th

drive shaft

9

spigot

10

link guide

11

First end

12

Second end

13

Handle

14

Elastic element, in particular spring

15

machine use

16

axis

17th

object

18

casing

19

camp

20

end surface

21

grinding area

A

longitudinal axis

B

pin axis

C

double arrow

D

angle of deflection

Claims (10)

1. Hand-held sanding tool (1) having a motor (6) and a gear unit (7) which drive an oscillating drive means (2) about a deflection angle (D), this drive means (2) moving a sanding belt (3) fastened to it in a reciprocating manner, the sanding belt (3) forming a loop which can be placed around a workpiece to be sanded, characterized in that the sanding belt (3) can be connected to form a closed ring by the two ends of the sanding belt (3) being releasably connected directly to one another by means of a fastener (4), in particular by means of a hook-and-loop fastener.
2. Sanding tool (1) according to Claim 1, characterized in that the drive means (2) is an oscillation head (5), which in particular has the shape of a wheel.
3. Sanding tool (1) according to either of the preceding claims, characterized in that the gear unit (7) has a drive shaft (8) at the end face on its side remote from the motor (6), on which drive shaft (8) a pin (9) which is in engagement with the drive means (2) is arranged eccentrically.
4. Sanding tool (1) according to Claim 3, characterized in that the eccentric pin (9) is arranged at an angle to the drive shaft (8) which is the same size as the deflection angle (D) of the drive means (2).
5. Sanding tool (1) according to Claim 4, characterized in that the pin (9) sits in a slotted-link guide (10) on the drive means (2).
6. Sanding tool (1) according to one of the preceding claims, characterized in that the fastener (4) is formed on the first end (11) and on the second end (12) of the sanding belt (3).
7. Hand-held sanding tool (1) having a motor (6) and a gear unit (7) which drive an oscillating drive means (2) which moves a sanding belt (3) fastened to it in a reciprocating manner, the sanding belt (3) being arranged with its first end (11) on the drive means (2), characterized in that its second end (12) is connected to a handle (13).
8. Sanding tool (1) according to Claim 7, characterized in that an elastic element (14), in particular a spring, is arranged between the second end (12) of the sanding belt (3) and the handle (13).
9. Sanding tool (1) according to either of Claims 7 and 8, characterized in that the first end (11) of the sanding belt (3) is rotatably attached to the drive means (2).
10. Sanding tool (1) according to one of Claims 7 to 9, characterized in that the drive means (2) is a machine insert (15).

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