EP1409206B1 - Hammer drill and/or paving breaker with a handle - Google Patents

Description

The invention relates to a hand-held drilling and / or percussion hammer according to the preamble of claim 1.

Drills and / or impact hammers, hereinafter referred to as hammers, depending on the intended use according to various design concepts produced. Hammers with low electrical power consumption and light weight are generally handled with one hand executed in "pistol form". For higher demands on performance of such a hammer leads to a correspondingly enlarged Diameter of an electric motor used in the hammer, in general a common universal motor, but a disadvantageous large distance between a percussion axis and the handle. This considerable misalignment therefore results in hammers with larger electrical Power consumption, which carried out according to this design concept would be to an unfavorable center of gravity and excessive Nick vibrations, resulting in a deteriorated handling of the hammer.

To improve the handling of a hammer with at least medium electrical power consumption is another design concept known this is a so-called spade handle in the area of the percussion axis provides, so that the aforementioned misalignment only one assumes a low value. The commonly used universal motors with collectors, however, have a relatively large axial length, which with an arrangement of these engines behind a striking mechanism of the hammer would have led to a large overall length of the hammer, which in turn the Handling of the hammer for the operator impaired. For this Reason it was customary so far that the universal motors of this power class for larger hammers exclusively perpendicular to the impact or Drilling axis were arranged.

Document GB-A-2 154 497 discloses a hammer drill according to the preamble of claims 1 and 6.

The invention is based on the object, a hand-held drilling and / or Specify impact hammer that has compact outer dimensions.

According to the invention, the object is achieved by a hand-held drilling and / or Hammer with the features of claim 1 solved. advantageous Further developments of the invention are in the dependent claims Are defined.

An inventive hand-held drill and / or percussion hammer, hereinafter referred to as a hammer, has an electric motor, one of which Electric motor drivable percussion, an electric motor and the Schlagwerk receiving housing and a handle on, the so on the housing is formed, that a gripping position in an extension a striking axis of the striking mechanism is located. Here is the axis of rotation the motor shaft of the electric motor with the impact axis paraxial.

The arrangement of the handle at the height of the striking axis allows one Operation of the hammer without annoying pitching vibrations while aligning the motor shaft a significant reduction in manufacturing costs Result has, because the number of required components are significantly reduced can. Thus, the structure of the invention is particularly suitable for hammers medium performance class or above.

In an advantageous embodiment of the hammer, the electric motor be formed of a three-phase motor, further in the housing a converter for supplying power to the three-phase motor with a suitable Power frequency is provided. By the three-phase motor can be significantly reduce the overall length of the hammer in its longitudinal direction, because a three-phase motor does not compare to a universal motor only builds shorter due to the omission of a collector, but this engine type can also be shorter by the length of one or both engine mounts, since this unlike the universal motor due to the absence of a far over the end faces of the rotor core packet protruding winding on the rotor can be installed in the winding of the stator.

In an advantageous further development, a wobble shaft device can be arranged in the housing be provided, which is a rotary motion of the three-phase motor converted into a float for the percussion, wherein the three-phase motor - based on the striking axis in horizontal position - above the wobble shaft and behind the percussion - so between percussion and handle - can be arranged. By the arrangement the three - phase motor behind the percussion section, so that the Rotary axis of the motor shaft of the three-phase motor with the main working direction is axially parallel, results in an advantageous short overall length of Hammer.

Another embodiment of the invention is characterized in that that a wobble shaft device is provided in the housing, which is a Rotary motion of the AC motor into a float for that Schlagwerk converts, with the three-phase motor below the percussion and below the wobble shaft device, each based on the Schlagachse in horizontal position, can be arranged. The resulting total length This embodiment is extremely short, resulting in a excellent handling of the hammer. In a variant of this Embodiment, the handle formed on the housing is a spade handle, the three-phase motor in a region of the housing below the spade handle can be arranged.

In the aforementioned embodiment of the hammer, the converter for reasons of space U-shaped and above the striking mechanism and above the wobble shaft device, based on the Schlagachse in horizontal position, be arranged. This possible configuration the converter has the advantage that unnecessary voids in the housing can be filled in accordance with the converter, which is reflected in the compact outer dimensions of the hammer. Further This can efficiently dissipate the heat loss generated in the converter the housing can be discharged to the outside.

In a particularly advantageous embodiment of the hammer is on the Housing formed a spade handle. This can be an offset between the main working direction of the hammer and a point of attack either greatly reduced or too high for a major operator's hand Become zero, which is in terms of applying higher pressure forces and a fatigue-free use with prolonged use of the hammer is advantageous.

A small overall length in the longitudinal direction of the hammer of the above-explained Embodiments comprising a wobble shaft device can, is also achieved by the impact mechanism as a hollow piston impactor is executed, with hollow drive piston and movable therein Impact piston, wherein the wobble shaft device as a drive for the Hollow piston impact mechanism is used. Opposite tube impactors with crankshaft and connecting rods, which are common in this performance class, build the hollow piston impact testers with wobble shaft drive in the axial direction much more compact.

The particular advantage of the described hammer is that on the one hand the total number of mechanical parts can be reduced and on the other hand, the cost of these mechanical parts has been significantly reduced can be. With similar features as conventional Hammering this performance class can not only cost advantages, but also achieve weight advantages. Consequently, the inventive Hammer in terms of manufacturing costs, safety, ease of use and Durability extremely beneficial.

Another embodiment of the invention is characterized in that that the electric motor is a universal motor. In this embodiment may be formed on the housing a spade handle, wherein further the universal motor in a lower housing bar, d. H. in one area the housing below the spade handle, can be arranged. These Arrangement advantageously leads to a small total length of the hammer in its longitudinal direction, despite the inherently longer design of the universal motor in relation to the three-phase motor.

These and other features and advantages of the invention will become apparent below using exemplary embodiments with reference to the Figures explained in more detail.

Show it:

Fig. 1

a basic structure of a first embodiment of the hammer according to the invention in a side sectional view;

Fig. 2

a basic structure of a second embodiment of the hammer according to the invention;

Fig. 3

a basic structure of an embodiment of the hammer; not part of the patent appeal

Fig. 4

a basic structure of a fourth embodiment of the hammer according to the invention.

In Figs. 1 to 4 are respectively a basic structure of a first to fourth Embodiment of a hammer and / or percussion hammer according to the invention 1, hereinafter referred to as hammer, in a side sectional view shown. The first to fourth embodiments shown in Figs is common that a housing 2 is provided, in which one end a tool holder 3 arranged with a chuck 4 stored is, in which a tool (not shown) can be clamped. A shaft 3a of the tool holder 3 leads into the housing 2 and is by means of a first bearing device 5 is mounted in the housing 2 about a first axis 6. From the illustrations in Figs. 1 to 4 it can be seen that the first Axis 6 parallel to a horizontal main working direction of the hammer. 1 is that results from the orientation of the tool holder 3 and the Longitudinal or impact axis of a tool corresponds.

For safe handling of the hammer 1 is on the housing 2 in height the first bearing device 5, a handle 7 attached. The handle 7 extends in its longitudinal direction substantially perpendicular to Main working direction of the hammer, whereby, when an operator the Handle 7 engages around with one hand, a reliable support of the torque by the operator is possible.

At the opposite end of the housing 2 is a jug or spade handle 8 trained, embrace the operator with her main hand can. The spade handle 8 is in two places, i. above and below hinged to the housing 2. As can be seen in the figures, is by the provision the spade handle 8 ensures that the gripping position, ie the main hand of the operator always substantially at height or in Extension of the first axis 6 and thus also the striking axis is located, resulting in a favorable center of gravity and avoiding vibrations and disadvantageous pitching oscillations about the first axis 6. Further, in an upper portion of the spade handle 8 is an operation switch 8a provided by the operation of the operator Hammer 1 in operation or can put out of service. The operation switch 8a is also arranged approximately in extension of the striking axis to the desired To get gripping position.

Furthermore, all embodiments shown in FIGS. 1 to 4 are common, in that within the shaft 3a leading into the housing 2 Tool holder 3, a striker 3b is arranged. The striker 3b is in the Shaft 3a in a direction parallel to the axis 6 and zur Hauptarbeitsrichtung movable. In an area in the housing 2 behind the storage facility 5, with respect to the main working direction or the striking axis, is a Schlagwerk 9 provided, which is designed as a hollow piston impaction. The Schlagwerk 9 has a percussion piston 10, the impact piston 10th in a known manner driving drive piston 11 and a percussion tube 12, in which the unit consisting of the percussion piston 10 and the drive piston 11 is movably guided parallel to the axis 6. A longitudinal axis the impact mechanism 9 is coaxial with the first axis. 6

At an end of the percussion mechanism 9 opposite the tool holder 3 is at the end of the drive piston 11, a flange 13 with a guide eye 14 provided, wherein at a portion of the percussion tube 12, the extends over the flange 13, an external toothing 15 is formed.

At its opposite end of the tool holder 3, the percussion works 9 with a wobble shaft device 16 together, via a second Bearing device 18 is mounted in the housing 2 and one to the first Axis 6 parallel second axis 17 can be driven by rotation. A first pin 19 is by means of a third bearing means 20 at a Main body of the wobble shaft device 16 is provided and extends at an angle to the second axis 17. A free end of the first pin 19 is rotatably supported in the guide eye 14 of the flange 13. Further the main body of the wobble shaft means 16 has a second pin 21 with an external toothing 21a, wherein the second pin 21 in such a way axially parallel to the percussion 9 and the percussion tube 12 extends, that the external teeth 21 a of the second pin 21 with the external teeth 15 of the percussion tube 12 is engaged.

The wobble shaft device 16 described above makes it possible, on the one hand, that the percussion tube 12 of the percussion mechanism 9 via the second pin 21 is rotated, which consequently leads to a rotation of the Tool holder 3 for a drilling function of the hammer 1 leads. Furthermore the first pin 19 passes during a rotation of the wobble shaft device 16 about the second axis 17 continuously from a first working position "A" to a second working position "B" and back to the first Working position "A". By the storage of the free end of the first pin 19 in the guide eye 14 is thus the flange 13 and thus the drive piston 11 of the striking mechanism in a reciprocating motion parallel to first axis 6 offset.

By a coupling device (not shown) can be adjusted accordingly be whether a rotational movement of a motor to be explained below in a rotational movement of the percussion tube 12 or in a striking movement the drive piston 11 and thus the percussion piston 10 is converted is, or if there is a superposition of the rotational movement of the striking tube 12 with the translational reciprocating motion of the drive piston 11 and the percussion piston 10 for a simultaneous drilling and impact of the hammer 1 is coming.

A tool (not shown) is so in the chuck 4 of the tool holder 3 insert that it is positively in the radial direction, and thus movable in the horizontal direction parallel to the main working direction is. The striker 3b is configured such that a tool holder 3 facing first end thereof adjacent to the chuck 4. A the percussion 9 facing the second end of the striker 3b extends so by the shaft 3a that it is with an end face of the percussion piston 10 in Can contact.

In a drilling function of the hammer 1, a rotational movement of the Schlagwerkrohrs 12 transmitted via the shaft 3a to the tool holder 3, wherein due to a force applied to the hammer 1 contact pressure to a work surface a recorded in the chuck 4 end of the Tool abuts the first end of the striker 3b, which in turn with its second end abuts the end face of the percussion piston 10. The Rotation of the tool holder 3 becomes to the in a radial direction transferred form-fitting in the chuck 4 used tool, so that perform a drilling function of the hammer 1.

In the event that a beating function of the hammer 1 is to be achieved, beats in a reciprocating motion of the drive piston 11 and the Impact piston 10, the end face of the percussion piston 10 against the striker 3b, by which this movement on the tool used in the chuck 4, that is movable in the horizontal direction parallel to the main working direction is transferred. As mentioned above, the rotational movement of the Tool holder 3 readily with a reciprocating motion of the drive piston 11 and the percussion piston 10 and the striker 3b superimposed , which results in a simultaneous drilling and impact function of the hammer 1 sets.

The above-explained features are all the first to fourth embodiments together. Hereinafter, the respective embodiments in terms of their differences in detail.

In Fig. 1, a first embodiment of the hammer 1 is shown at a three-phase motor 23 via a fourth bearing means 24 in the housing 2 above the wobble shaft 16 and behind the percussion 9 is recorded.

A three-phase motor is generally characterized in that it due to the omission of the otherwise usual in universal motors collector a having small dimension in the axial direction. The axial length of this Motor type can also be reduced by the length of the engine mounts, since this in contrast to the universal motor due to the absence of a lot over the End faces of the rotor laminated core projecting winding on the rotor in can be installed in the area of the winding of the stator.

A decisive feature of this embodiment is that the three-phase motor 23 is accommodated in the housing 2 in such a way that an axis of rotation 25 of a motor shaft 26 of the three-phase motor 23 is axially parallel to the first axis 6 or the main working direction of the hammer 1. The above-mentioned aspects result in that the overall length L _{GES of} the hammer 1 in its longitudinal direction is smaller compared to hammers of this power class if a universal motor were installed in such a way that its motor axis would be parallel to the main working direction. For hammers in this class, shortening in the range of 50 to 70 mm can be assumed.

In this first embodiment, below the three-phase motor 23 in FIG a portion of the housing between the wobble shaft means 16 and the spade handle 8, a converter 27 arranged to the three-phase motor 23 to provide energy accordingly. The converter 27 may be suitable be fed with single-phase AC power and forms the Mains current in a suitable for the three-phase motor 23 current.

The motor shaft 26 of the three-phase motor 23 has at a free end, the in alignment with one on the main body of the wobble shaft device 16 trained flange toothing 28 is an external toothing 29, which is in engagement with the flange toothing 28. To this Way, it is possible the rotation of the motor shaft 26 of the three-phase motor 23 to the wobble shaft device 16 to transmit.

In Fig. 2 is a second embodiment of the invention in a lateral Section view shown. This second embodiment is broad identical to the first embodiment, wherein like reference numerals are used for the same components, their explanation at this point not repeated. Unlike the first embodiment is here the three-phase motor 23 in a region of the housing 2 below the Spade handle 8 is arranged. In addition, in the second embodiment the converter 27 behind the striking mechanism 9 and above the wobble shaft device 16, each related to the main working direction arranged.

In a third embodiment of the hammer 1, from that in Fig. 3 a basic structure is shown in a side sectional view, is a outer shape of the housing 2 compared to the first embodiment and modified to the second embodiment in that in this case the Three-phase motor 23 below the hammer mechanism 9 and below the wobble shaft device 16, each related to the main working direction arranged is. Both in the second and in the third embodiment the converter 27 is formed in a U-shape and above the striking mechanism 9 and arranged above the wobble shaft device 16, respectively related to the main field of work. By training in the U-shape it is possible that through the converter 27 spaces in the housing 2 suitable, resulting in compact external dimensions of the hammer 1 effects. In other words, this form of the Arrangement of the converter 27 advantageous because they have very little space in the Housing 2 takes. Furthermore, can be through the U-shape in the Converter 27 resulting heat loss efficiently through the housing 2 after leave outside. The remaining components of the third embodiment are substantially identical to those of the first and second embodiments.

FIG. 4 shows a basic structure of a fourth embodiment, which is essentially identical to the second embodiment explained above. In contrast to the second embodiment, however, a universal motor 30 is accommodated here in the housing 2 instead of a three-phase motor, which has a larger dimension in the axial direction due to a separate motor bearing outside the winding of the stator. Due to the advantageous arrangement of the universal motor in the housing 2, wherein the axis of rotation 25 of the motor shaft 26 of the universal motor 30 is axially parallel to the main working direction, however, can be achieved in the fourth embodiment, a reduced overall length L _GES compared to hammering this class, if in these the electric motor would be arranged in the housing as shown here.

Despite the compact outer dimensions, the various embodiments of the hammer 1 according to the invention, due to the above explained design concept, a generous dimensioning of the essential components, such as the first to fourth storage facilities 5, 18, 20, 24, the first and second pins 19, 21 and the external teeth 15, 21a, 29, too. This results in a high load capacity and a advantageous long life with a superior impact performance of Hammers 1.

Claims (6)

1. Hammer drill and/or percussion hammer (1), having:

   an electric motor (23; 30),

   a percussion mechanism (9) which can be driven by the electric motor (23; 30),

   a housing (2) which accommodates the electric motor (23; 30) and the percussion mechanism (9), and having

   a handle (8) which is formed on the housing (2) such that a gripping position is located at the level of an extension of a percussion axis (6) of the percussion mechanism (9),

   wherein the axis of rotation (25) of a motor shaft (26) of the electric motor (23; 30) is axially parallel with the percussion axis (6),
   characterised in that the electric motor (23; 30) is disposed in a region of the housing (2) beneath the handle (8), with respect to the percussion axis in a horizontal position.
2. Hammer drill and/or percussion hammer (1) as claimed in Claim 1, characterised in that

   the electric motor is a three-phase motor (23), and in that

   a converter (27) is provided in the housing (2) for supplying the three-phase motor (23) with energy.
3. Hammer drill and/or percussion hammer (1) as claimed in Claim 2, characterised in that a wobble shaft device (16) is provided in the housing (2) and converts a rotational movement of the three-phase motor (23) into a reciprocating movement for the percussion mechanism (9).
4. Hammer drill and/or percussion hammer (1) as claimed in [Claim] 2 or 3, characterised in that the converter (27) is formed in a U-shaped manner and is disposed above the percussion mechanism (9) and above the wobble shaft device (16), in each case with respect to the percussion axis in the horizontal position.
5. Hammer drill and/or percussion hammer (1) as claimed in Claim 1, characterised in that the electric motor is a universal motor (30).
6. Hammer drill and/or percussion hammer (1), having:

   an electric motor (23; 30),

   a percussion mechanism (9) which can be driven by the electric motor (23; 30),

   a housing (2) which accommodates the electric motor (23; 30) and the percussion mechanism (9), and having

   a handle (8) which is formed on the housing (2) such that a gripping position is located at the level of an extension of a percussion axis (6) of the percussion mechanism (9),

   wherein the axis of rotation (25) of a motor shaft (26) of the electric motor (23; 30) is axially parallel with the percussion axis (6),
   characterised in that

   the electric motor is a three-phase motor (23),

   a converter (27) is provided in the housing (2) for supplying the three-phase motor (23) with energy, and in that

   the three-phase motor (23) is disposed, with respect to the percussion axis in a horizontal position, above the wobble shaft device (16) and behind the percussion mechanism (9), i.e., between the percussion mechanism (9) and the handle (8).

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