GB2340442A

GB2340442A - Planing head

Info

Publication number: GB2340442A
Application number: GB9918293A
Authority: GB
Inventors: Josef Jeker
Original assignee: Scintilla AG
Current assignee: Scintilla AG
Priority date: 1998-08-14
Filing date: 1999-08-03
Publication date: 2000-02-23
Anticipated expiration: 2019-08-03
Also published as: GB2340442B; DE19837029B4; DE19837029A1; GB9918293D0

Abstract

A plane head for a manual plane machine has a profiled base body 11 with a support surface 13 for clamping a plane cutter 12 which is fastened to the base body 11 with a shell-like clamping jaw 21 resting on this, where, for low cost production without loss of quality in the planing process, the area of the base body 11 diametrically opposed to the support surface 13 with the plane cutter 12 is structured with the same mass as the cutter-carrying area and with an arc-shaped outer contour which, together with the outer contour of the remaining base body area and the clamped shell-like clamping jaw 21, forms a closed circle. Also disclosed is an embodiment (Fig. 3) where the area of the base body 11 diametrically opposed to the support surface 13 has radial slots (Figure 3, 28) cut into an arcuate surface to balance the opposing mass.

Description

2340442 Planing Head The invention is based on a planing head for a manual

plane according to the preamble of claim 1.

In a known planing head of this type, also called a cutter block (DE 4137 623 AI or EP 0 048 303 B 1), the profiled base body attached to a shaft is formed cylindrically with diametrically opposed flats where each flat forms a support surface for a plane cutter held radially immobile on the support surface concerned by means of a pressure plate, clamping jaw and clamping bolts. Each pressure plate here engages with a lug in a groove formed on the cutter back and clamps the plane cutter against the support surface. '111e required radial protrusion of the cutting edge of the plane cutter over the outer contour of the base body is set by moving the pressure plate along the support surface. The pressure plate is held immobile on the support surface by means of adjustrnent screws screwed into the base body. The clamping jaw now attached rests with one side of its shell edge on the pressure plate and the other side on the support surface and is clamped by means of the clamping bolts screwed into the base body such that the plane cutter is held immobile in a tight fit. The cylindrical section outer contours of the two shell-like clamping jaws together with the arc-shaped residual periphery of the profiled base body give the cylindrical shape of the plane head.

Advantages of the Invention The plane head according to the invention with the features of claim 1 has the advantage that by omission of a second diametrically opposed plane cutter it is cheap to produce without loss of quality in the planing result compared with a twin-cutter 2 plane. The mass balance between the cutter carrier area and the cutter- free area, which is necessary to avoid imbalance in the planing 'head, can easily be achieved constructionally in the design phase using 3D CAD process. The circular form of the plane head prescribed in VDE 0740/1214 is achieved either by corresponding shaping of the base body or by the attachments giving the circular form.

The measures listed in the further claims are advantageous flu-ther developments and improvements of the plane head specified in claim 1.

According to a preferred design form of the invention, the profiled base body has two parallel support surfaces of the same shape facing away from each other. One support surface is occupied with the plane cutter and on the other is attached, resting on this, a cover shell of arc-shaped outer contour. The cover shell has indentations with flat recessed bases containing holes and is clamped to the support surface by the recessed bases by means of clamping bolts passing through the holes, where the shell edges of the cover shell press on the support surface. This design allows the existing production equipment for conventional twin-cutter planes to be used unchanged for production of the cheaper single cutter plane. Only the cover shell need be modified slightly in relation to the clamping jaw as this is clamped only to the support surface and is not like the clamping jaw - resting on the support surface and pressure plate.

Drawings The invention is explained in more detail in the description below using the design examples shown in the drawing. These show:

3 Fig 1 a top view of a plane head for a manual plane in direction of arrow I in Fig 2, Fig 2 a cross section of the plane head along line II-11 of Fig 1, Fig 3 a cross section of a plane head according to a further design example.

Description of the Design Examples

The plane head shown in Fig 1 in top view and in Fig 2 in cross section for a manual planing machine has a profiled base body 11 which sits rotationally fixed on a shaft 10 and carries a plane cutter 12 protruding radially over the outer contour of the base body 11. The plane head is held in rotating bearings in a housing of the planing machine by its shaft ends which protrude axially over the base body 11 and is coupled to an electric motor via one shaft end. The profiled cylindrical base body 11 is flattened on two diametrically opposed sides, forming two parallel support surfaces 13 and 14 of the same shape which face away from each other. Each support surface 13 or 14 has a raised centre part 131 and 141 and two side edge areas 132, 133 and 142, 143 lying on the two sides of the centre part which are set back in relation to the centre part and of unequal width. Due to the point-symmetrical shape of the base body 11, the side edge areas of the same width 132, 142 and 133, 143 lie diametrically opposite each other on the two support surfaces 13, 14.

The plane cutter 12 is clamped to one support surface 13, where a defined radial protrusion of the cutting edge of the plane cutter 12 over the outer contour of the base body 11 is set. For this, the plane cutter 12 has on its cutter back facing away from support surface 13, a groove 15 in which engages a rib-like lug 16 as a tight fit, where 4 this lug in turn is formed on a pressure plate 17 lying on the cutter back of the plane cutter 12. After adjusting the radial protrusion of the plane cutter 12, the pressure plate 17 can be attached to the centre part 131 of the support surface 13 by means of two adjustment screws 19, each of which penetrates through a slot 18 in the pressure plate 17 and are screwed into corresponding threaded holes 20 in the base body 11. Thereupon, a shell-like clamping jaw 12 with arc-shaped outer contour is placed on support surface 13 and clamped to the base body 11 by means of clamping bolts, where the clamping jaw 21 rests on one side on the back of pressure plate 17 facing away from plane cutter 12 and on the other side oil the side wall area 133 of the support surface 13. The clamping bolts to fasten the clampingjaws 21 are not shown in Figs 1 and 2 but correspond to the clamping bolts 22 in the area of support surface 14 which are explained later. Like these clamping bolts 22, the heads of the clamping bolts for the clamping jaw 21 lie in indentations M tile clamping jaw 2 1, are pushed through holes in the bases of the recesses and screwed into corresponding threaded holes in the base body 11. It should be mentioned that a claniping groove 23 is arranged just off plane cutter 12, recessed into the base body 11.

To produce the required cylindrical form of the plane head, a cover shell 24 with arcshaped outer contour is clamped on the support surface 14, where this shell differs from the shell-like clamping jaw 21 only in that with its edge it rests exclusively on the support surface 14. In the cover shell 24 are recessed three indentations 25 arranged at longitudinal distance from each other, the recessed bases 251 of which have a hole 26 for pushing through the clamping bolt 22. By means of the three clamping bolts 22, each of which can be screwed into a threaded hole 27 in the base body 11, the cover shell 24 is clamped with its three recessed bases 251 onto the centre part 141 of the support surface 14, where the two shell edges rest on the side wall areas 142 and 143 flush with the outer contour of the base body 11. The cover shell 24 is structured with regard to its weight as heavy as the clamping jaw 21 with pressure plate 17, plane cutter 12 and adjustment screws 19, so that the plane head as a whole is balanced.

According to a finther design example, the plane head shown in cross section in Fig 3 is modified in relation to the plane head described above in that the base body I V is a cylinder with a flat formed on one side only, support surface 13. In the same way as described in Fig 2, the plane cutter 12 with pressure plate 17, adjustment screw 19 and clamping jaw 21 is clamped onto support surface 13, where the plane cutter 12 again protrudes radially over the outer edge of the base body 1 V so that the cutter edge can engage in a workpiece to remove chips. The area of base body I F diametrically opposed to the support surface 13 has an arcshaped outer contour so that base body I Pwith attached clampingjaw 21 as a whole again has a cylindrical form. To compensate for imbalance, radial slots 28 are cut in the area of base body 11' diametrically opposed to the support surface 13, where the width and radial depth of the said slots are determined by the degree of weight reduction of this base body area required to compensate for imbalance. The radial slots 28 extend over the entire length of base body 11'.

6

Claims

1. Plane head for a manual plane machine with a profiled base body (11) which has a support surface (13) for clamping a plane cutter (12) protruding radially over the outer contour of the base body (11), and with. a shell-like clamping jaw (2 1) which rests on the pressure plate (17) and on the support surface (13) and which clamps the plane cutter (12) to the base body (11) and with an arc-shaped outer contour supplements the peripheral line of the base body (11) into a circle, characterised in that the area of the base body (11) diametrically opposed to the support surface (13) has the same mass as the cutter-carrying area and an arc-shaped outer contour which together with the outer contour of the remaining base body area and the clamped shell-like clamping jaw (2 1) forms a closed circle.

2. Plane head according to claim 1, characterised in that the profiled base body (11) has two parallel support surfaces (13, 14) of the same shape and facing away from each other, one of which is occupied with the plane cutter (12), and that on the other support surface (14) is attached a cover shell (24) with an arc-shaped outer contour resting on the said support surface.

3. Plane head according to claim 2, characterised in that the cover shell (24) has indentations (25) with a flat recessed base (25 1) and a hole (26) in this, and that the cover shell (24) is clamped with the recessed bases (25.1) to the support surface (14) by means of clamping bolts (22) passing through the holes (26) and screwing into threaded holes (27) in the base body (11).

4. Plane head according to claim 3, characterised in that the cover shell 7 (24) presses with its shell edges on the support surface (14).

5. Plane head according to any of claims 1 to 4, characterised in.that the plane cutter (12) lies as a tight fit against a pressure plate (17) and the pressure plate (17) is clamped against the support surface (13) by means of adjustment screws (19) and the clamping jaw (2 1) fastened by means of clamping bolts screwed into the base body (11) presses on the pressure plate (17) and on the support surface (13).

6. Plane head according to claim 5, characterised in that the support surfaces (13, 14) each have a raised centre part (13 1, 14 1) on which are clamped on the one side the pressure plate (17) for radial fixing of the plane cutter ( 12) and on the other side the recessed bases (25 1) of the cover shell (24), while the shell edges of the clamping jaw (2 1) and the cover shell (24) rest on the outer side edge areas (132, 13 3, 142, 143) of the support surface (13, 14) which are set back in relation to the centre parts (131, 141).

7. Plane head according to claim 6, characterised in that the profiled base body is shaped point- symmetrically.

8. Plane head according to claim 1, characterised in that the base body (11) is a cylinder with a flat formed on one side which forms the support surface (13) for clamping the plane cutter (12) and that in the area of the base body (11) diametrically opposed to and facing away from the support surface (13) are cut radial slots with the width and radial depth necessary to compensate for the imbalance.

9. A plane head substantially as herein described with reference to the accompanying drawings.