Tool on a tool carrier for tilling and comminuting

Abstract

A tool for tilling and comminuting in a tool carrier with rotor which is rotatable about the rotor axis, the tool is received in a receptacle of the tool carrier arranged on the rotor. The receptacle is formed by a first face provided in the cutting direction and second face on which the tool is fastened by means of its face which faces away from the cutting direction, the tool has a body which has an end face in the direction of rotation of the rotor and a rear face opposite the end face. The rear face is inclined by 1° to 10° with respect to the end face and the tool is braced and held between the face in the cutting direction of the receptacle and the face of the receptacle that faces away from the cutting direction, play is left between the tool and receptacle base.

Claims

1. A tool for grinders and mulchers arranged in a tool holder for a tool holder rotor rotatable about an axis of the tool holder rotor; the tool being housed in a single seat of the tool holder arranged on the tool holder rotor; the single seat being formed by a front portion of the tool holder provided in a cutting direction and a rear surface portion of the tool holder onto which the tool is fixed; the front portion of the tool holder contacts only a small bottom surface portion of the tool whereas the rear surface portion of the tool holder contacts a large surface portion of the tool; a surface area of the large surface portion of the tool contacted by the rear surface portion of the tool holder being many times larger than a surface area of the small bottom surface portion of the tool contacted by the front portion of the tool holder; the tool is supported exclusively between a small bottom surface portion of the front portion of the tool holder in the cutting direction of the single seat and the rear surface portion of the tool holder; a single mechanism allowing easy removal of the tool from the tool holder; the tool having a body which has a front surface in the cutting direction of the tool holder rotor contacted only by the small bottom surface portion of the front portion of the tool holder, and a rear surface opposite the front surface of the body, wherein the rear surface is inclined in the range of 1° to 10° with respect to the front surface; the tool is fitted and supported between the front portion of the tool holder in the cutting direction of the single seat and the rear surface portion of the tool holder; and a clearance exists between the tool and a bottom of the single seat.

2. The tool according to claim 1, wherein the rear surface of the tool has a recess and this recess comprises an upper part and a lower part inclined 10°-90° from the upper part in the direction of the front surface of the tool.

3. The tool according to claim 1, wherein the rear surface of the tool has a recess and this recess is formed by a first upper part substantially parallel to the rear surface of the tool and a second lower part which is inclined 10° to 90° from the first upper part in the direction of the front surface of the tool.

4. The tool according to claim 1 wherein the single mechanism is a bolt through an upper part of the tool holder.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further characteristics and details of the invention will be apparent from the claims and from the following description of a preferred non-limiting embodiment as shown in the accompanying drawings, in which:

(2) FIG. 1 is a front view of a tool-holder rotor of the invention,

(3) FIG. 2 is a sectional view of a tool-holder rotor of the invention,

(4) FIG. 3 is a perspective view of a tool-holder rotor of the invention,

(5) FIG. 4 is a front view of a tool of the invention,

(6) FIG. 5 is a cross-sectional view along A-A of FIG. 4 of a tool of the invention,

(7) FIG. 6 is an enlarged view of a tool received in in a tool holder, and

(8) FIG. 7 is a magnified view A of FIG. 6.

DETAILED DESCRIPTION OF THE INVENTION

(9) In FIG. 1 a tool-holder rotor is designated by numeral 100. Tool holders 20 are arranged on the tool-holder rotor 100. Each tool holder 20 forms a seat for a tool 1. The tool holder 20 is composed of a front portion 21 in the working direction, a lower portion 23 and a rear portion 22 including a through hole for a bolt 30.

(10) The tool 1 for grinders, mulchers and the like, is arranged in a tool holder 20 for a tool-holder rotor 100 rotating about the axis of the rotor. This tool 1 is received in a seat of the tool holder 20 on the tool-holder rotor 100. The tool holder 20 is formed by a front portion 21 disposed in the cutting direction and a rear portion 22 upon which the tool is fastened with its surface that faces away from the cutting direction. The tool 1 has a body 2 with a front surface 2a oriented in the direction of rotation of the rotor, and a rear surface 2b that faces away from the front surface 2a.

(11) According to the invention, the rear surface 2b is inclined by an angle of 1° to 10° with respect to the front surface 2a.

(12) This means that the angle β ranges from 1° to 10°.

(13) The tool 1 is only clamped and supported between the front portion 21 oriented in the cutting direction of the seat and the rear portion 22 that faces away from the cutting direction of the tool 1, a clearance being left between the tool and the bottom of the lower portion 23.

(14) The tool is fastened at its top by means of a bolt 30 that extends through the tool holder 20 in the rear portion 22 and is tightened in the hole 31 of the tool.

(15) Advantageously, the tool 1 has a recess on its rear surface 2b. This recess is formed by a first upper portion substantially parallel to the rear surface of the tool and a second lower portion which is inclined toward the front surface by an angle of 10° to 90°, therefore, the angle α ranges from 190° to 270°. This facilitates removal, as a backward rotation of the lower portion of the tool can occur when the back of the tool head is loaded with a force applied opposite to the direction of rotation of the tool.

(16) Furthermore, the central recess is complementary to a raised portion on the rear surface of the rear portion 22. This affords easier and more accurate positioning.

(17) The tool and the seat are made of steel and the cutting edge 3 is preferably made of special steel.

(18) The bolt 30 for fastening the tool is preferably introduced from the back in the tool holder seat. This avoids exposure of the bolt head to processing wear, which might hinder its removal.

(19) FIG. 6 shows a tool holder 20 with a tool 1 received therein. The cutting direction 10 is designated by arrow. The tool 1 is clamped in the tool holder 20 at the contact area 11 between the front portion of the tool holder 21 and the front surface of the tool 2a, at the contact area 12, between the rear portion 22 of the tool holder and the rear surface 2b of the tool, with a clearance 13 being left between the lower surface 2c of the tool and the lower portion 23 of the tool holder.

(20) By this arrangement, as discussed above, the tool will not move in the working direction because it is also locked by the bolt 30, which prevents wear of the tool holder 20 and the bolt 30.

(21) The tool is released by removing the bolt and hitting the back of the tool 1 in the working direction 10.

(22) It will be finally appreciated that the tool and tool holder as described heretofore are susceptible of additions, changes or variants that would be obvious to the skilled person, without departing from the scope of the invention as defined by the appended claims.

LIST OF REFERENCE NUMBERS

(23) 1 tool

(24) 2 tool body

(25) 2a front surface of the tool in the cutting direction

(26) 2b rear surface of the tool in the cutting direction

(27) 2c lower surface of the tool

(28) 3 cutting edge

(29) 10 cutting direction

(30) 11 contact area

(31) 12 contact area

(32) 13 clearance

(33) 20 tool holder

(34) 21 front portion of the tool holder

(35) 22 rear portion of the tool holder

(36) 23 lower portion of the tool holder

(37) 30 bolt

(38) 31 bolt hole in the tool body

(39) 100 rotor

(40) α angle of the rear surface of the tool

(41) β angle between the front and rear surfaces of the tool