WO2007073955A1

WO2007073955A1 - Hand power tool, in particular drill hammer and/or chipping hammer

Info

Publication number: WO2007073955A1
Application number: PCT/EP2006/067846
Authority: WO
Inventors: Gerhard Meixner
Original assignee: Robert Bosch Gmbh
Priority date: 2005-12-22
Filing date: 2006-10-27
Publication date: 2007-07-05
Also published as: DE102005061402A1

Abstract

The invention relates to a hand power tool, in particular a drill hammer and/or chipping hammer, comprising a hammer unit (10a - 10d) with a transmission unit (12a - 12d) that is designed to transmit a drive force from an axial drive unit (14a - 14d) to a piston unit (16a - 16d). According to the invention, the transmission unit (12a - 12d) has coupling points (18a - 18d, 20a - 20d), whose height can be adjusted.

Description

20. 12. 05

ROBERT BOSCH GMBH; D-70442 Stuttgart

Hand tool, in particular drill and / or chisel hammer

State of the art

The invention relates to a hand tool, in particular a drill and / or chisel hammer, according to the preamble of claim 1.

EP 1 238 759 B1 discloses a generic hand-held power tool, namely a chipping hammer, having a hammer mechanism unit which has a transfer unit formed by a connecting rod which is used to transfer a drive force from an axial drive unit formed by an eccentric to a piston unit having. The connecting rod is rectilinear, runs parallel to a striking axis of the percussion unit and has at a high level, ie perpendicular to the impact axis or direction of movement of a piston of the piston unit and parallel to bearing axes of the percussion unit and in particular parallel to a motor shaft, formed by connecting rods Anlenkstellen on , Advantages of the invention

The invention relates to a hand tool, in particular a drill and / or chisel hammer, with a percussion werkeinheit having a transmission unit, which is provided for transmitting a driving force from an axial drive unit to a piston unit.

It is proposed that the transmission unit has connection points arranged at a higher offset. In this case, "high offset" is to be understood in particular a distance in a direction that is unequal to an axial direction or a direction of impact and in the direction of a bearing axis of the power tool, as particularly preferably in the direction of a motor axis or a rotation axis of a motor shaft, if this to a Impact axis includes an angle other than zero. The distance between the articulation points or between centers of the articulation points is preferably greater than half the longitudinal extent of at least one articulation point and particularly preferably greater than a total longitudinal extent of a articulation point. An "axial drive unit" is to be understood in particular as meaning a unit which converts a rotational movement into an axial movement, such as in particular a swash bearing or an eccentric etc. Furthermore, a "pivot point" should be understood to mean, in particular, a point via which the transmission unit communicates with the Axialantriebseinheit is coupled, and a point via which the transmission unit is coupled to the piston unit. By means of a corresponding design according to the invention, a particularly flexible construction spatial design allows and it can be a total of space, especially height, saved.

Highly offset articulated points can be achieved in a structurally simple and cost-effective manner if the transfer unit has at least one deflection means with at least one angling, in particular a height difference, and / or if the transmission unit has at least one transmission means, which in at least a partial area is a height difference having effect, extending obliquely to a striking axis alignment.

If the transmission means has at least one bend, the transmission means is preferably formed in a region of the bend with a reinforcement, whereby increased loads in the region of the bend can be advantageously taken into account. The reinforcement may be formed by an increased material thickness and / or width and / or may also be formed by one or more struts or other constructive embodiments that appear appropriate to the person skilled in the art.

If the transmission unit is designed in several parts, a large height offset can be achieved structurally and a high degree of design flexibility can be achieved, in particular if the transmission unit has a pusher unit and a connecting rod unit. Here, a "thrust unit" is to be understood as a unit which essentially carries out a purely axial movement and is articulated on the piston unit, and under a "connecting rod unit" a unit which, in addition to an axial movement, has a compensating unit. movement, in the first place a pivoting movement, executes and is articulated on the axial drive unit.

The solution according to the invention can be used in all hand-held power tools that appear suitable to the person skilled in the art, but particularly advantageously in hand-held power tools which have a motor with a motor axis which encloses an angle not equal to zero, preferably greater than 30 ° and particularly preferably greater than 45 °, to the striking axis. so that the motor can be integrated to save space, especially for particularly powerful hand tool machines.

If the axial drive unit comprises an eccentric, high powers can be transferred in a structurally simple and cost-effective manner.

In a further embodiment of the invention it is proposed that the eccentric is mounted at least on a side facing away from the engine. In this context, "a side facing away from the engine" should be understood to mean that a bearing of the eccentric in the direction of a motor axis or a rotational axis of a motor shaft, starting from the engine, at least partially behind a starting point of the eccentric, in particular behind an eccentric is. By an appropriate design, in turn, a space optimization can be achieved and space can be saved, in particular if the eccentric is mounted only on one side, in particular based on a driven means of the eccentric, such as an eccentric, an eccentric cam, etc. It is also proposed that the power tool has a ball head bearing at at least one point of articulation of the transmission unit, whereby unwanted tension can advantageously be easily avoided.

drawing

Further advantages result from the following description of the drawing. In the drawing exemplary embodiments of the invention are shown. The drawing, the description and the claims contain numerous features in combination. The person skilled in the art will expediently also consider the features individually and combine these into meaningful further combinations.

Show it:

1 is a schematic longitudinal section through a hand tool,

2 shows schematically illustrated individual parts of an alternative hand tool in a plan view,

3 shows a section along the line III-III in Figure 2,

4 a schematically illustrated longitudinal section through an alternative hand tool with an eccentric mounted on a side facing away from the motor, Fig. 5 is a schematically illustrated longitudinal section through an alternative hand tool with a multi-part Ubertragungseinheit and

Fig. 6 is a detail of a plan view of a

Impact unit of the power tool of Figure 5.

Description of the exemplary embodiments

Figure 1 shows a schematic longitudinal section through a chisel hammer with a percussion unit 10a, which has a transmission unit 12a, which provided for transmitting a driving force from an eccentric formed by an axial drive unit 14a to a piston unit 16a and to a guided in a hammer tube 48a piston 50a is. The transmission unit 12a is essentially formed by a connecting means 22a designed as a connecting rod and has connecting points 18a, 20a formed by connecting rods or have the articulation points 18a, 20a or their centers 42a, 44a, which are formed by the connecting rods, in the direction of a motor axis 34a or a rotational axis of a motor shaft 40a of an electric motor 32a has a spacing 46a, which preferably corresponds to at least half the extent of a pivot point 18a, 20a in the direction of the motor axis 34a. The chipping hammer has a so-called L-type construction, in which the motor shaft 34a encloses an angle of 90 ° to a striking axis 26a.

The transmission means 22a is in the piston unit 16a facing pivot point 18a via a ball head bearing 36a coupled with the piston 50a and in the axial drive unit 14a facing pivot point 20a via a not-shown radial ball bearing with an eccentric pin 54a of the eccentric. The eccentric has a spur gear 52a meshing with the motor shaft 40a, on the side of the eccentric pin 54a facing away from the electric motor 32a. The eccentric is mounted on one side relative to the eccentric pin 54a or relative to the spur gear 52a on a side facing the electric motor 32a.

The transmission means 22a has two opposite angled portions 24a, 24a ', each with approximately 45 °, so that the transmission means 22a between the angled portions 24a, 24a' extend obliquely to the striking axis 26a and have a substantially S-shaped side contour having.

In the figures 2 to 5 further exemplary embodiments are shown. Substantially constant components and functions are in principle labeled with the same reference numerals, with the letters a-d being added to differentiate the exemplary embodiments. The following description is limited essentially only to the differences from the exemplary embodiment in FIG. 1, while with regard to the same components, features and functions, reference may be made to the description of the exemplary embodiment in FIG.

FIG. 2 shows individual parts of a percussion unit 10b of an alternative chisel hammer. The impact mechanism unit 10b has a transmission unit 12b which is adapted to transmit a drive force from an axial movement formed by an eccentric. drive unit 14b is provided to a piston unit 16b and to a guided in a hammer tube piston 50b. The transmission unit 12b is essentially formed by a transmission means 22b in the form of a connecting rod and has highly staggered articulation points 18b, 20b formed by connecting-rod eyes. The transmission means 22b has two opposite bends 24b, 24b ', each about 90 °, wherein a height difference or a distance 46b in the direction of a motor axis 34b essentially by the length of a perpendicular to a striking axis 26b and parallel to the motor axis 34a extending, around an axis parallel to the motor axis 34b extending axis curved intermediate stub 38b between the angled portions 24b, 24b 'of the transmission means 22b is determined (Figures 2 and 3).

Starting from the articulation point 20b facing the axial drive unit 14b, the transmission means 22b has an increasing width up to the angled portions 24b, 24b ', so that the greatest width 56b of the transmission means 22b adjusts in the region of the angled portions 24b, 24b' and thus a reinforcement. Furthermore, the intermediate piece 38b in the area of the striking axis 26b has its greatest strength 58b, which decreases perpendicular to the motor axis 34b and perpendicular to the striking axis 26b or transverse to the striking axis 26b. Starting from the angled portions 24b, 24b 'in the direction of the piston unit 16b, the transmission means 22b is curved and extends in a region adjoining the taper with a constant width up to the articulation point 18b facing the piston unit 16b. FIG. 4 shows a schematic longitudinal section through an alternative chipping hammer with a percussion unit 10c, which has a transfer unit 12c, which transmits a driving force from an axial drive unit 14c formed by an eccentric to a piston unit 16c or to a hammer tube 48c Piston 50c is provided. The transmission unit 12c is essentially formed by a connecting rod 22c in the form of a connecting rod, and has connecting points 18c, 20c formed by connecting rods, or points of articulation 18c, 20c formed by the connecting rods or their centers 42c, 44c in the direction of one Motor axis 34c and a rotational axis of a motor shaft 40c of an electric motor 32c has a distance 46c. The chipping hammer has a so-called L-type construction, in which the motor shaft 34c encloses an angle of 90 ° to a striking axis 26c. The electric motor 32c is disposed in a motor housing 60c that connects to a gear housing 62c toward the axial drive unit 14c and to a hammer tube housing 64c toward the piston unit 16c.

The motor shaft 40c protrudes in both directions beyond a laminated core of the electric motor 32c and is mounted at an end remote from the eccentric in the motor housing 60c and at an end facing the eccentric in the gear housing 62c, starting from the electric motor 32c in the axial direction of the motor axis 34c behind a combing with the motor shaft 40c spur gear 52c of the eccentric. The motor housing 60c has, in the direction of the gear housing 62c, an intermediate cover 66c with a recess 68c through which the motor shaft 40c passes. In the recess 68c is one between the Mo- toroidal shaft 40c and the intermediate cap 66c sealing gasket 70c arranged by means of an engine compartment in the motor housing 60c is sealed against a gear chamber in the gear housing 62c.

The eccentric is mounted on one side facing away from the electric motor 32c side in the gear housing 62c, while on the electric motor 32c facing side of the spur gear 52c of the eccentric pin 54c is arranged.

The transmission means 22c essentially has, starting from the articulation point 20c facing the axial drive unit 14c up to the articulation point 18c facing the piston unit 16c, an orientation which results in a height difference between the articulation points 18c, 20c and extends obliquely to the striking axis 26c.

FIG. 5 shows a schematic longitudinal section through an alternative chisel hammer with a percussion unit 10d, which has a transfer unit 12d, which transmits a drive force from an axial drive unit 14d formed by an eccentric to a piston unit 16d or to a hammer tube 48d Piston 50d is provided. The transmission unit 12d is designed in several parts and has a push unit 28d and a connecting rod unit 30d. The connecting rod unit 30d forms a first pivot point 20d facing the axial drive unit 14d and is essentially formed by a transfer means 22d designed as a connecting rod which is rectilinearly aligned parallel to a striking axis 26d, the transfer means 22d basically comprising bends and / or could also be aligned obliquely to a striking axis 26d. The transmission means 22d is drive-coupled with a second connecting rod eye 72d and via a bearing pin 74d with a plate-shaped body 76d of the pushing unit 28d. The plate-shaped body 76d is in the axial direction of a motor shaft 34d of an electric motor 32d by means of two on its top side and by means of two abutting on its underside plain bearing means 78d, 8Od and is perpendicular to the motor axis 34d and perpendicular to the axis of impact 26d on the side next to the plate-shaped body 76d arranged plate-shaped plain bearing means 82d led (Figure 6). The plate-shaped slide bearing means 82d are used in particular for damping transverse forces of the connecting rod unit 30d. The chisel hammer has a so-called L-type construction, in which the motor axis 34d encloses an angle of 90 ° to the impact axis 26d.

The thrust unit 28d, which is guided essentially parallel to the striking axis 26d, has, starting from the plate-shaped body 76d, a web 84d running obliquely to the striking axis 26d and a web 86d extending perpendicularly to the striking axis 26d and parallel to the motor axis 34a, which in a parallel or coaxial with the striking axis 26d extending web 88 d einstuckig, which forms a pivot point 18 d of the transfer unit 12 d, via which the transmission unit 12 d is coupled to the piston unit 16 d. The articulation points 18d, 20d of the transmission unit 12d or their center points 42d, 44d have a spacing 46d in the direction of the motor axis 34c or a rotation axis of a motor shaft 4Od of the electric motor 32d. 20. 12. 05

ROBERT BOSCH GMBH; 70442 Stuttgart

reference numeral

10 percussion unit 56 width

12 transmission unit 58 strong

14 Axial drive unit 60 Motor housing

16 piston unit 62 gearbox housing

18 Anlenkstelle 64 Hammerrohrgehause

20 pivot point 66 intermediate cover

22 transmission means 68 recess

24 bend 70 seal

26 striking axis 72 connecting rod eye

28 thrust unit 74 bearing pin

30 connecting rod 76 body

32 Motor 78 plain bearing

34 Motor axle 80 plain bearing means

36 Kuge1köperspreizung 82 Gleitlagermittel

38 intermediate piece 84 bridge

40 motor shaft 86 bridge

42 center 88 footbridge

44 center

46 distance

48 hammer tube

50 pistons

52 spur gear

54 eccentric pins

Claims

20. 12. 05ROBERT BOSCH GMBH; D-70442 Stuttgart claims

1. Hand tool, in particular drill and / or chisel hammer, with a Schlagwerkinheit (10a - 1Od), the one

Transfer unit (12a - 12d), which is provided for transmitting a driving force from an axial drive unit (14a - 14d) to a piston unit (16a - 16d), characterized in that the transfer unit (12a - 12d) arranged high offset drive points (18a-18d, 20a-20d).

2. Hand tool according to Claim 1, characterized in that the transmission unit (12a - 12d) at least one transmission means (22a - 22d) having at least one angled portion (24a - 24d).

3. Hand tool according to Claim 2, characterized in that the transmission means (22a - 22d) in a region of the bend (24a - 24d) has a gain.

4. Hand tool according to one of the preceding claims, characterized in that the Ubertragungs- unit (12a, 12c, 12d) at least one Ubertragungsmittel (22a, 22c, 22d), which in at least a Teilbe- rich a height difference between the articulation points ( 18a, 18c, 18d, 20a, 20c, 2Od) causing, obliquely to a striking axis (26a, 26c, 26d) extending alignment.

5. Hand tool according to one of the preceding claims, characterized in that the Ubertragungs- unit (12d) is formed of several parts.

6. Hand tool according to Claim 5, characterized in that the transmission unit (12d) has a pusher unit (28d) and a connecting rod unit (30d).

7. Hand tool according to one of the preceding claims, characterized by a motor (32a - 32d) with a motor axis (34a - 34d), which encloses to the striking axis (26a - 26d) an angle not equal to zero.

8. Hand tool according to one of the preceding claims, characterized in that the Axialantriebs- unit (14a - 14d) comprises an eccentric.

9. Hand tool according to Claim 7 and 8, characterized in that the eccentric is mounted at least on a side facing away from the motor (32c).

10. Hand tool according to at least claim 8, characterized in that the eccentric is mounted on one side.

11. Hand tool according to one of the preceding claims, characterized by a ball head bearing (36a - 36d) at at least one articulation point (18a - 18d) of the transmission unit (12a - 12d).