Oscillation damper

The invention relates to a vibration damper for a tool such as a hammer, a chisel hammer or similar.

From DE 34 05 922 C2 it is known to the percussion of a The tool against the housing of the tool to store damped. This should occur shock and vibration damped be transferred to the handle and on the operator. Such a design requires a high constructive Effort. The sprung mounting of the percussion mechanism must already taken into account in the design of the tool will. Retrofitting in existing tools is not possible.

The invention is based on the object, a vibration damper create, which transferred to the operator vibrations reduced.

This object is achieved by a vibration absorber with the Features of claim 1.

The suspension arranged mass body allows good damping the vibrations. As mass body is particularly an existing component of the tool used. In this way, an additional mass body weight increase of the tool would cause, can be avoided.

However, it may be expedient, an additional mass body to use for vibration damping. This is in a separate Housing resiliently mounted. The arrangement of the vibration in a separate housing enables easy Retrofitting to existing tools. simultaneously can by the resilient suspension of a mass body in the Housing of the vibration absorber good attenuation occurring Vibrations of the tool can be achieved.

Suitably, the vibration absorber means for Fixation on the housing of a tool. Particularly the housing of the vibration damper form-locking or force-locking fixable to the tool. This can be a easy retrofitting to existing tools to realize, without modifications to the tool itself are necessary.

For a good vibration damping of the vibration damper is in a location on the tool can be fixed, in which the direction of movement the mass body parallel to the longitudinal axis of the Tool disposed tool insert lies. In drilling and Chisel hammers is the main direction of vibration in the direction the longitudinal axis of the tool bit. By fixing the Vibration damper in such a tool, that the mass body parallel to the longitudinal axis of the tool bit movable is the main vibration can be damped. to also To dampen vibrations in other directions, provided that a mass body in two or three directions of movement and movable relative to the housing of the vibration damper is spring. The mass body can thus multiaxial layered damp vibrations. However, it may also be expedient to two or three mass body in different Movement directions to store mobile. Around to achieve a sufficient vibration damping, is provided, that the suspension of the mass body in each direction of movement the mass body on the oscillations of the tool is tuned in this direction. To a small size to achieve the vibration damper, is provided, that at least one mass body made of hard metal.

An embodiment of the invention will be hereinafter the drawing explained. The sole drawing shows a tool with a vibration absorber arranged thereon in a schematic representation.

The tool 1 is in particular a rotary hammer. The tool 1 has a housing 2 in which is formed a handle 3 is. In the grip 3 opens a conduit 7 for supply the electric power tool 1 with power. In the area of Handle 3, the tool 1 a control lever 4. furthermore a tool holder 5 is provided, in which a Tool insert 13 can be arranged. is on the housing 2 a selector lever 6 is provided, with which the operating mode of the tool 1 can be switched. Depending on the position of the selector lever 6, the tool bit 13 in rotation about the longitudinal axis 14 or beating along the longitudinal axis 14 or with a combined rotating and striking movement driven.

On the housing 2 of the tool 1, a vibration absorber 8 is arranged. This consists of a housing 9, in which a mass body 10 is arranged. The mass body 10 is in the direction of movement 12 movably supported. The mass body 10 based in the movement direction 12 of a spring 11 against the housing 9 of the vibration damper 8 from. The mass body 10 consists in particular of hard metal. It can, however, Other materials, particularly severe materials, be expedient. The mass body 10 may consist of several individual Components be formed. The spring shown schematically 11 can also be composed of several individual springs be.

The housing 9 of the vibration damper 8 is of the housing 2 Tool 1 releasably attached. Fixation can positively his or positively. In particular, the vibration damper 8 means for fixing the housing 2 of the tool 1 on.

can accrue beating drive the tool bit 13 Vibrations in the direction of the longitudinal axis 14 of the tool insert 13. The direction of movement 12 of the mass body 10 runs parallel to the longitudinal axis 14. By the vibration of the Tool 1 of the mass body 10 is also to vibrations excited. This allows total damped oscillations are so act less vibration to the operator.

It may be appropriate that the mass body 10 in two or three directions of movement is movable. are particular the directions of movement perpendicular to each other thereby, so that Vibrations can be damped in every direction. Around to achieve a good vibration damping, is the mass of the Mass body 10 and the spring constant of the spring 11 to the Vibrations of the tool 1 matched. It may be advantageous be more mass body in the housing 9 of the vibration 8 to arrange that each movable in other directions of movement are supported. However, it may also be expedient, for each direction of movement a separate vibration absorber each with a movably mounted body mass and provide a spring. In order to adapt the vibration absorber 8 to allow the generated vibrations can be provided that adapted the spring constant of the spring 11 can be.

Suitably are known as a mass body suitable components of the tool, such as the oil cooler used and resiliently against the housing of the tool stored. The mass body should advantageously have a weight of 5% possess up to 10% of the weight of the tool. By using existing components, only the springs as additional mass required. The mass body is advantageously of a heavy material, such as tungsten carbide. Hereby, a compact design can be achieved.

Suitably, the vibration absorber as a multiaxial absorber educated. Especially with pneumatic hammers with wobble drive Crankshaft or contact vibration in several axes on. By two or three axis vibration absorber an increased vibration reduction can be achieved.

Advantageously, the absorber is designed as adaptable absorber. This allows for existing tools vibration reduction be achieved by up to 50%.