EP1858676B1

EP1858676B1 - Cutter head with fast knife replacement system

Info

Publication number: EP1858676B1
Application number: EP06704506A
Authority: EP
Inventors: Alfredo Ferreira De Abreu
Original assignee: Individual
Current assignee: Individual
Priority date: 2005-03-14
Filing date: 2006-02-09
Publication date: 2008-12-10
Anticipated expiration: 2026-02-09
Also published as: DE602006004189D1; WO2006098647A1; ATE416897T1; PT103245A; ES2322397T3; EP1858676A1

Abstract

The head has a fast knife replacement system consisting of a lever tool (9), which acts upon gibbs for making the gibbs to go down by inserting respective rods on cutter head tops. A magnet tool (1) acting directly upon knives allows the insertion or removal of the knives in a space open by the lever tool. A main body is composed of a lathe-turned and rectified steel cylinder with slots for the gibbs and the knives, and a boring is provided at the tops to receive discs (10).

Description

FIELD OF THE INVENTION

This invention refers generically to equipment for cutting wood and in particular to the replacement of knives in a cutter head which equips one, two, three or four-sided planers and that can also be used for the machining of other materials that allow planing like plastics, chipboard, medium-density timber, corks and others.

SUMMARY OF THE INVENTION

The new system of cutter head knife replacement in this invention was conceived having in mind several goals, as follows:

a) The fast replacement of cutter head knive, by means of a tool system which consists of a tool actuating as a lever and another tool functioning as a magnet;
b) The saving of operating time due to the system efficiency;
c) The dismounting and mounting of knives without the need of touching them with the hands, therefore granting total physical safety for the operator.

The system of fast cutter head knife replacement in this invention consists mainly of two special operating tools and of the changing carried out on the main cylindrical body of the cutter head.

BACKGROUND OF THE INVENTION

There are various cutter head tools known in the state of the art, for instance, patent US 2002/174912 provides a base assembly for a portable planing machine having a base structure, plate structure and a plurality of fasteners, where the fasteners couple the plate structure to the base structure such that the plate structure is supported by the support surface. But still this technology doesn't provide free area features for quick tool replacement action upon specific pins.
Another cutter tool is described in patent US 6279444 where to change the cutter, the locking of the clamping jaw is done by a spring-loaded bolt that engages a recess provided in the clamping jaw. This solution is also visibly different from the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 shows a perspective exploded view of the cutter head;
Fig. 2 shows a partial top view of the cutter head top (12);
Fig. 3 shows a set of views of the lever tool (9);
Fig. 4 shows a set of views of the magnet tool (1);
Fig. 5 shows a perspective view of the whole system;
Fig. 6 shows a top view with a detail of how the lever tool (09) acts;
Fig. 7 shows a view with the representation of the unlocking;
Fig. 8 shows the profile of the knife (02).

DETAILED DESCRIPTION

The fast knife replacement device consists of two tools. The first one, the lever tool (09), is an arm composed of a central rod and two ribs fixed at its extremities with the suitable configuration; this rod is of variable length since it adapts to the cutter head cylinder length and the arm is used for knife unlocking. The ribs are rectangular shaped and recessed (a) in one of the ends so as to allow fitting into the cutter head and to rest on the supporting pins. The second tool, the magnet tool (01), is a handle consisting basically of a rectangular frame, which has a magnet coupled at the extremity with the function of attracting the knife (02) either to remove it from the slot where it is lodged or to place it there.
The cutter head is completed with two steel circular discs (10) which are placed at the cylinder extremities and fixed with screws (6) to the said cutter head. These discs (10) are machined at half thickness in order to leave free access space (b) for the entrance of the tool which is going to act upon the gibb pins (03) inserted in the inner sides of the discs (10) and in the ends of the gibbs (04).
Designed this way, the cutter head with rotating movement can be bored inside for application in a solid shaft of a planer, or it can also be built in solid steel and embedded spindle, with bearings and pulley. Depending on its diameter, the cutter heads may have 2, 3, 4, 5, 6, 8, 10, or 12 knives (02).
The cutter head knives are profiled knives (02) in high speed steel (HSS) with 16% or 18% hardened and rectified wolfram (W) with plane and double cut configuration, to be inserted in the slots (11) and fixed with the above mentioned gibbs (04). The steel knives (02) of adapted configuration, which have a trapezoid profile with a recess in the smaller parallel side , will get the shape of the head slot(11) inner wall profile, as they are tightened by the pressure exerted by the gibb (04).

DESCRIPTION OF THE TOOL OPERATION PROCESS

The system of fast knife replacement now disclosed can be described as follows:
Each knife (02) can be inserted or removed from the cutter head in an easy and fast way without being touched by the hand of the operator.
For this purpose, two specific tools have been developed (Fig. 3 and 4): tool (09) (Fig. 3 and 7) is inserted with one hand in the ends of the cutter head until one feels that the tool stops on the recess (a) having reached the gibb pins (03) (Fig. 1 and 2) placed on the ends of the gibb (04) (Fig. 1 and 2), producing then a lever movement (pushing the tool rod downwards) (Fig. 7); the pressure exerted on the back of the tool ribs against the pins (13) (Fig. 1 and 7) which are placed on the discs (10) (Fig. 1 and 5) makes the gibb (04) (Fig. 1 and 2) go down in all its length. Holding the magnet tool (01) (Fig. 4) with the other hand, one must put the magnet close to the knife (02) attracting it and then replace it in the free access space (b of Fig. 6). Finally, loosen and remove the lever tool (09) previously inserted allowing this way that the rectangular steel bars (07) (Fig. 1) placed on the cutter head base force the ascent of the gibb (04), positioning efficiently the knife (02) in its respective place; the tools may be removed then.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In order to understand the invention better, we describe next as a non-limitative example a preferred embodiment of the cutter head and the tools as per this invention, referring the drawings that are here attached with the figures that represent:

Fig. 1, a perspective view, with the parts detached, which shows schematically the main body, a cutter head knife (02), a fixing gibb (04), the two end discs (10), the knife replacement tools; the arch-shaped rectangular steel bars (7) and the screws (5);
Fig. 2, a partial view of the cutter head top which shows the profile of the slots (11) in the main body (08), a gibb (04) in position with the knife (02) and the movements of the knife (02) replacement and gibb (04) drive devices;
Fig. 3, a view of the lever tool (09) that drives the gibb (04) and allows the knife (02) release, referring the lever tool recesses (a) with the gibb pins (03);
Fig. 4, a view of the tool that removes or inserts the knife (02) in its place;
Fig. 5, a view in perspective of the whole system, with the cutter head knives, the fixing gibbs (04) inserted into the slots (11) of the main body (08) and the knife (02) replacement tools in working position;
Fig. 6, a view that shows in detail how the unlocking tool actuates, making the gibb (04) go down and creating free access space (b) for the knives (02);
Fig. 7, a view that shows the movement that needs to be executed upon the unlocking lever tool (09) so that it makes the gibb (04) go down.
Fig. 8, shows the profile of the knife (02) to be used;

With reference to the drawings, one can see in Fig. 1 the main body (08) composed of a lathe-turned and rectified steel cylinder, with slots (11) for the gibbs (04) and knives (02), and boring (12) at the ends to receive the discs (10). The knife (02) unlocking lever tool (09) in Fig. 3, inserted in the space between the gibb (04) ends and the discs (10) in Fig. 5 and pressed, makes the gibb (04) go down.

Claims

Cutter head with fast knife replacement system for planers of wood and other similar materials that allow planing, having a main body (08) composed of a lathe-turned and rectified steel cylinder, with slots (11) for knife fixing gibbs (04) and knives (02), characterized by a cutter head knife application system composed by two circular steel discs (10) recessed on the inner lateral side and screwed to each of the cutter head ends, with pins (13) on the inner lateral side in the same number of the knives (02) and gibb pins (03) on the two ends of the gibbs (04), allowing, with the use of tools, the release and replacement of the knives (02) from a free access space (b).
Cutter head according to claim 1 characterized by the fact that the gibbs (04) act upon the knifes (02) when pressed by rectangular steel bars (07).
Cutter head according to claim 1 characterized by the foreseen usage of a lever tool (09) which, inserting the respective rods on the cutter head tops and pressured, acts upon the gibbs (04) making it go down and this way open the space (b) where the knife (02) will be inserted.
Cutter head according to claim 1 characterized by the foreseen usage of a magnet tool (01) which, acting directly upon the knife (02), allows the insertion or removal of the same knife (02) in the space open (b) by the lever tool (09).
Cutter head according to claim 1 characterized by HSS steel knives (02) with 16% or 18% wolfram (w), the profile of which is a trapezoid with a recess in the smaller parallel side.