Cutter head for a brush cutter

Patent metadata

Field	Value
Publication number	US-12029159-B2
Application number	US-202117338760-A
Country	US
Kind code	B2
Filing date	Jun 4, 2021
Priority date	Jun 15, 2020
Publication date	Jul 9, 2024
Grant date	Jul 9, 2024

Abstract

A cutter head for a brush cutter has a base body with top base body part and bottom base body part. A screw element is arranged at the bottom base body part for attachment to an output shaft of the brush cutter. A receptacle for fastening a cutting tool is provided between top and bottom base body parts. The base body is rotatably driven in operation of the brush cutter about an axis of rotation of the base body. The top and bottom base body parts are held together by a detachable snap-on connection. The snap-on connection is positioned at a distance, measured in a radial direction, from the axis of rotation of the base body. The distance amounts to at most 40% of the cutter head diameter. For releasing the snap-on connection, the top and bottom base body parts are pulled apart from each other by a pulling force.

First claim

What is claimed is:

1. A cutter head for a brush cutter, the cutter head comprising:
a base body comprising a top base body part and a bottom base body part, wherein the base body is configured to be rotatably driven in operation of the brush cutter about an axis of rotation of the base body;
a screw element arranged at the bottom base body part, wherein the screw element is configured for attachment to an output shaft of the brush cutter;
a receptacle configured to fasten a cutting tool, wherein the receptacle is arranged between the top base body part and the bottom base body part;
wherein the top base body part and the bottom base body part are held at each other by a releasable snap-on connection;
wherein the snap-on connection is positioned at a radial distance from the axis of rotation of the base body, wherein the radial distance is measured in a radial direction relative to the axis of rotation of the base body, wherein the distance amounts to at most 40% of a diameter of the cutter head;
wherein the top base body part comprises a collar arranged in an interior of the top base body part, wherein the collar surrounds a central opening of the top base body part;
wherein the bottom base body part comprises an interior region, wherein the interior region is a securing sleeve, wherein the securing sleeve is arranged in the central opening of the top base body part in a mounted state of the cutter head;
wherein, in the mounted state of the cutter head, the snap-on connection is arranged in the central opening of the top base body part in a protected position enclosed by the securing sleeve of the bottom base body part.

2. The cutter head according to claim 1 , wherein the radial distance amounts to at most 30% of the diameter of the cutter head.

3. The cutter head according to claim 2 , wherein the receptacle comprises a bearing axis extending parallel to the axis of rotation of the base body, wherein the bearing axis is positioned at a distance from the axis of rotation of the base body, wherein the distance of the bearing axis from the axis of rotation of the base body is larger than the radial distance of the snap-on connection from the axis of rotation of the base body.

4. The cutter head according to claim 1 , wherein the snap-on connection comprises one or more gripping hooks and one or more holding contours in operative connection with the one or more gripping hooks, respectively.

5. The cutter head according to claim 4 , wherein the one or more gripping hooks are arranged at the top base body part and the one or more holding contours are arranged at the bottom base body part.

6. The cutter head according to claim 4 , wherein the one or more gripping hooks each comprise a hook head configured to engage the one or more holding contours, respectively.

7. The cutter head according to claim 6 , wherein the hook head is configured such that the snap-on connection is locked when pushing together the top base body part and the bottom base body part, and such that the snap-on connection is unlocked when pulling apart the top base body part and the bottom base body part.

8. The cutter head according to claim 4 , wherein the central opening of the top base body part is a cup-shaped opening and wherein the one or more gripping hooks are arranged protected in the cup-shaped opening of the top base body part.

9. The cutter head according to claim 4 , wherein the one or more gripping hooks are bendable or flexible in a radial direction away from the axis of rotation.

10. The cutter head according to claim 9 , wherein the one or more gripping hooks each comprise a hook head with a slanted contact surface configured to contact the respective holding contour, wherein the slanted contact surface is positioned at a slant in relation to the axis of rotation, wherein, upon pulling apart the top base body part and the bottom base body part, the slanted contact surface of the hook head glides across the holding contour to disengage the hook head from the holding contour and to unlock the snap-on connection.

11. The cutter head according to claim 4 , wherein the securing sleeve comprises a holding opening for each one of the one or more gripping hooks, wherein the one or more gripping hooks are threaded into the holding opening, respectively, when the top base body part and the bottom base body part are pushed together.

12. The cutter head according to claim 11 , wherein the holding opening is arranged at an end face of the securing sleeve of the bottom base body part.

13. The cutter head according to claim 4 , wherein the one or more holding contours are arranged at the securing sleeve of the bottom base body part.

14. The cutter head according to claim 1 , further comprising a disruptive contour at one of the top base body part and the bottom base body part and further comprising a guide groove interacting with the disruptive contour and arranged at the other one of the top base body part and the bottom base body part, wherein the guide groove extends in a direction of the axis of rotation of the base body, wherein the disruptive contour and the guide groove are configured to align the top base body part and the bottom base body part to each other in a circumferential direction in relation to the axis of rotation of the base body.

15. The cutter head according to claim 14 , wherein the snap-on connection is configured such that the snap-on connection locks only when the disruptive contour and the guide groove are aligned relative to each other.

16. The cutter head according to claim 14 , wherein the disruptive contour and the guide groove are configured to transmit torque in the circumferential direction between the top base body part and the bottom base body part.

17. The cutter head according to claim 14 , wherein the disruptive contour is formed at the collar.

18. The cutter head according to claim 14 , wherein the guide groove is formed at the securing sleeve.

19. The cutter head according to claim 1 , wherein the receptacle is a bearing bolt configured to arrange the cutting tool at the base body.

20. The cutter head according to claim 19 , wherein the bearing bolt is fastened with one end at the top base body part or at the bottom base body part.

21. The cutter head according to claim 19 , wherein the bearing bolt is fastened to the top base body part.

22. The cutter head according to claim 1 , wherein the screw element is fixedly secured at the bottom base body part so as to prevent rotation relative to the bottom base body part.

23. The cutter head according to claim 1 , wherein the receptacle is configured to pivotably support the cutting tool.

24. The cutter head according to claim 1 , wherein the snap-on connection is formed between an end face of the top base body part and an end face of the bottom base body part, wherein the end face of the top base body part and the end face of the bottom base body part are facing each other, wherein the end face of the top base body part is a bottom side of the top base body part and the end face of the bottom base body part is a top side of the bottom base body part.

25. The cutter head according to claim 1 , wherein the collar is an inner wall of the top base body part, wherein the inner wall extends in a direction of the axis of rotation of the base body.

26. A cutter head for a brush cutter, the cutter head comprising:
a base body comprising a top base body part a

Assignees

• Stihl Ag & Co Kg Andreas

Inventors

• Rethaber Achim

Classifications

• A01D34/82

  Other details · CPC title

• A01D34/736

  Flail type · CPC title

• A01D34/416

  Flexible line cutters · CPC title

• A01D34/68

  with motor driven cutters or wheels · CPC title

• A01D34/733 Primary

  Cutting-blade mounting means · CPC title