FR2513173A1 - Cutting head for vertical wood cutter - has cutter holder and two cutters for upward and downward cutting - Google Patents

Abstract

The cutting head (1) is for a vertical cutter and supports both a cutter holder (2) and pressure bar on a longitudinal fixed frame (5). This has an alternating vertical movement on the frame and it can also tilt on a cross frame axis. There is an upper cutter, working upwards (10), and another working downwards (11). These are fitted symmetrically on the tilting axis. At the opposite ends of the cutter the two cutter holders are pivoted on transverse axes (8) in side cheeks on the bar support, with an outlet passage between.

Description

 The present invention relates to a cutting carriage for vertical slicer, that is to say a machine intended for the manufacture of veneers and in which the piece of wood, fixed by scratching on a vertical table, is driven by a movement of vertical back and forth while the knife is mounted fixed and substantially vertical on the cutting carriage, the latter being driven by a horizontal advance movement corresponding to the thickness of the veneer. In addition, a pressure bar is placed in front of the cutting edge of the knife and is linked to the knife holder so as to prevent tearing and to ensure a clean cut.

 In this field, vertical slicers with a downward cut are known at present, in which the cutting edge of the knife is oriented upwards, the cutting of the veneers being carried out during the downward movement of the piece of wood. while the cart is stationary. At the end of the downward movement of the wood-holding table, a receding or tilting-type release movement is applied to the cutting carriage in order to prevent the knife and the pressure bar from remaining in contact with the workpiece. of wood during its sham movement. Conversely, at the end of the upward movement of the wood-holding table, the knife and the pressure bar are returned to the working position while communicating to the cutting carriage the advance movement corresponding to the desired thickness of veneer.

Dn also knows vertical slicers cutting upwards, in which the cutting edge of the knife is oriented downwards and the veneer is cut during the upward movement of the piece of wood, according to an identical process and reversed by The only difference between these two known types of vertical slicer being that the veneer sheet delivered at the exit of a type of machine is reLourn upside down compared to that delirious at weeding other type of machine
i should note however that these two
types of vertical slicer can only produce one veneer per complete cycle of the reciprocating movement of the piece of wood, which corresponds to a yield not exceeding 50 Ó. In addition, the veneers cut successively are all on the same face, either front or back, for a given type of slicer, which requires turning these veneers manually to control the quality of the cut on both sides. In addition, at the time of joining these piacages, the assembly operation requires turning my nueilent every other sheet to obtain a symmetrical wood design.

 Furthermore, when a vertical slicer of one of the two aforementioned types is used upstream of a continuous slicing line comprising a dryer, it is generally necessary to install between the slicer and the dryer a delicate and expensive device intended to bring together or tighten the veneer sheets to make them substantially contiguous.

 The present invention aims to remedy the aforementioned drawbacks by providing a cutting carriage by which a vertical slicer has a very high yield and directly cuts relatively adjoining veneers and automatically turned one over the next.

 In accordance with the invention, in a cutting carriage for vertical slicer, of the type supporting a knife holder and pressure bar holder assembly and mounted, on a fixed longitudinal frame, with horizontal advance movement towards a holder table wood mounted in vertical reciprocating motion on the frame, the assembly is tilted according to a small clearance around an axis transverse to the frame, journalled in the lateral uprights of the carriage, and comprises an upper knife for cutting the upright and a knife lower cutting going down, symmetrically arranged, cutting edges opposite, on either side of a bar with two pressure edges whose plane of symmetry passes through the tilting axis and which is mounted in an adjustable manner on a cylinder bar holder centered on said axis, the two knives being respectively mounted in an adjustable manner on upper and lower knife holders which symmetrically surround the bar cylinder at a sufficient distance for the p assage of the veneers cut alternately by the knives, the inside face of each of the knife holders having in cross section a shape generally complementary to that of the part opposite the outside face of the bar-carrying cylinder and the means for transporting the veneers being respectively associated with the lad-ite inner face of each of the knife holder and with said part opposite the outer face of the bar holder cylinder.

According to other characteristics
- at their longitudinal end opposite the knife, the two knife holders are articulated on transverse axes mounted in lateral flanges integral with the bar-carrying cylinder and form a central longitudinal passage for the removal of the veneers alternately provided by the means respective carriers, the two knife holders being able to be articulated together on common transverse axes
- The bar-carrying cylinder has, in cross section, a circular shape including a support spout for the pressure bar;
- A vertical slicer comprising a carriage of the aforementioned type further comprises means for synchronizing the tilting movement of the assembly with the reciprocating movement of the table and the advance movement of the carriage.

Other characteristics and advantages of the present invention will emerge more clearly from the description which follows, given with reference to the appended drawings in which
Figures 1 and 2 show schematic sectional views of a preferred embodiment of the cutting carriage according to the invention, respectively during cutting down and cutting up, certain elements such as conveyors, l the guide member and the lateral flange having been omitted or shown to be incomplete in one of the two figures for the sake of clarity.

 In these drawings, the same references designate the same elements.

 Referring to FIGS. 1 and 2, the cutting carriage for vertical slicer according to the invention is generally designated by 1 and has for example the shape of a U in cross section. In general, the carriage 1 is of the type supporting an assembly 2 with a knife holder and a pressure bar holder and is mounted, by means of a lower plate 3 forming for example the bottom of the U, on slides 4 a fixed longitudinal frame 5 which is arranged horizontally.

 Under the control of a suitable device known per se and comprising for example a mechanism 6 with nuts and lead screws, the carriage 1 can therefore carry out a horizontal advance movement towards a vertical wood-carrier table, which is not shown in for clarity. In known manner, such a table is mounted in vertical reciprocating motion on the frame 5, and a piece or wooden ball 7 to be cut is fixed to said table by scratching.

 According to the invention, the assembly 2 is pivotally mounted according to a small clearance around an axis 8 which is transverse to the frame 5, that is to say that this axis is arranged in a generally vertical plane but may have , relative to the horizontal, an inclination determined as a function of that of the cutting edge of the knife in the cutting position. In addition, the tilting axis 8 is journalled in the lateral uprights of the carriage 1, for example the lateral branches 9 of the U, only one of which is visible in FIGS. 1 and 2. According to an essential feature of the invention, the assembly 2 comprises an upper knife 10 for cutting on the way up and a lower knife 11 for cutting on the way down, arranged symmetrically, sharp facing each other, on either side of a bar 12 with two pressure edges 13 and 14, of which the plane of symmetry is represented by the dashed line 15 and passes through the tilting axis 8.

 The pressure bar 12 with two edges can be made in one piece, as shown in FIG. 2 or be made up of two twin bars as shown in FIG. 1. In all cases, the pressure bar 12 is mounted adjustable way on a bar cylinder 16 which is centered on the tilting axis 8.

 The two knives 10 and 11 are respectively mounted in an adjustable manner on upper knife holder 17 and lower knife holder 18 which symmetrically surround the bar holder cylinder 16 at a sufficient distance for the passage of the veneers 19, 20 cut alternately by the knives 10 and 11. More specifically, the inner face 21, 22 of each of the knife holders 17 and 18 has, in cross section, a shape generally complementary to that of the facing part 23, 24 of the outer face of the bar-carrying cylinder 16.

 In addition, conveyor means suitable for the veneers and known per se, for example conveyors 25 and 26 with facing belts, are respectively associated with the inner face 21, 22 of each of the knife holders 17 and 18 and with the part opposite 23, 24 of the outer face of the bar-carrying cylinder 16.

 According to another feature of the invention, at their longitudinal end 27, 28 which is opposite the knife 10 or 11, the two knife holders 17 and 18 are articulated on separate transverse a; es mounted in lateral flanges 29 , of which only one appears in FIGS. 1 and 2 and is better represented in FIG. 2, and which are integral with the bar-carrying cylinder 16. Preferably, the two knife holders 17 and 18 are articulated together on common transverse axes 30 of which only one is shown in FIGS. 1 and 2.

 In addition, said ends 27 and 28 of the knife holder 17 and 18 form a central longitudinal passage 31 for the removal of the veneers alternately supplied by the respective transport means 25 and 26, a member 32 for guiding the veneers that can be mounted on the cylinder 16 opposite the bar 12 at two pressure nets.

 Furthermore 3 the bar-carrying cylinder 16 can have any symmetrical shape in cross section, for example that of a rhombus whose long diagonal would correspond to the pressure bar 12 and to the guide member 32, while the edges associated with the small diagonal would be rounded. However, the bar-carrying cylinder 16 preferably has a cross section of circular shape comprising a support spout 33 for the pressure bar 12 and, optionally, a diametrically opposite spout forming the guide member 32.

 It should be noted that the carriage described above obviously includes all the devices necessary and known per se to allow the amplitude or the movement of the tilting movement of the assembly 2, the opening and the relative positions of the two to be adjusted. knife holder 17 and 18 relative to the bar cylinder 16, the pressure exerted by the edges 13 and 14 of the bar 12 as well as the distance and the angle of the knives 10 and 11, in particular the slight draft angle which n is not shown in the figures.

 It should also be noted that a vertical slicer comprising a trolley according to the invention obviously comprises suitable means known per se for synchronizing the tilting movement of the assembly 2 with the reciprocating movement of the table carrier. -wood and the advance movement of the carriage 1, these means generally comprising a central electronic computing unit.

 During operation, and referring first to Figure 1, when the carriage 1 has advanced towards the piece of wood 7 and the assembly 2 has tilted clockwise, so that the lower knife 11 and the corresponding pressure edge 14 are in the working position while the upper knife 10 and the associated edge 13 are in the release or withdrawal position, the vertical descent of the piece of wood 7 causes the cutting down from a plating 19 which is immediately taken up between the belts of the lower conveyor 26.

 When the wood-holding table reaches the end of its vertical downward movement, the carriage 1 advances by the thickness chosen for the veneer while the assembly 2 rocks counterclockwise, so that the knife upper 10 and the associated pressure edge 13 are in the working position while the lower knife 11 and the associated pressure edge 14 are in the retracted position, as shown in FIG. 2. In these conditions, the rise vertical of the table and the piece of wood 7 causes the cutting by going up of a veneer 20 which is immediately taken up by the belts of the upper conveyor 25, while the lower conveyor 26 drives the veneer 19, previously sliced down, until 'to the evacuation passage 31 at which it can be taken up by other external carriers not shown.

 When the timber table reaches the end of its vertical upward movement, the carriage 1 again advances by the thickness chosen for the veneers while the assembly 2 swings clockwise, so that a new cutting down can be done according to the process described above with reference to Figure 1.

 It should be noted that the speed of any external conveyors and that of the conveyors 25 and 26 can be advantageously synchronized with the speed of the slicing so that the veneers supplied by the machine are substantially contiguous while being alternately faced.

 It is understood that the present invention has only been described and shown for explanatory purposes but in no way limitative and that any useful modification may be made to it, in particular in the field of technical equivalences, without going beyond its ambit.

Claims (5)

 1. Cutting carriage for vertical slicer, of the type supporting a knife holder and pressure bar holder assembly and mounted, on a fixed longitudinal frame, with horizontal advance movement towards a wood-holding table mounted with vertical reciprocating movement on the frame, characterized by the fact that the assembly is tiltably mounted according to a small clearance around an axis transverse to the frame, journalled in the lateral uprights of the carriage, and comprises an upper cutting knife on the amount and a lower cutting knife descending, symmetrically arranged, cutting edges opposite, on either side of a bar with two pressure edges whose plane of symmetry passes through the tilt axis and which is mounted in an adjustable manner on a bar-carrying cylinder centered on said axis, the two knives being respectively mounted in an adjustable manner on upper and lower knife holders which symmetrically surround the bar holder cylinder at a sufficient distance for the passage veneers cut alternately by the knives, the inside face of each of the knife holders having in cross section a shape generally complementary to that of the part opposite the outside face of the bar-carrying cylinder and the means for transporting the veneers being respectively associated to said inner face of each of the knife holder and to said part opposite the outer face of the bar-carrying cylinder.  2. Trolley according to claim 1, characterized in that at their longitudinal end opposite the knife, the two knife holders are articulated on transverse axes mounted in lateral flanges integral with the bar-carrying cylinder and form a passage longitudinal central for the evacuation of the veneers alternately supplied by the respective conveying means.  3. Trolley according to claim 2, characterized in that the two knife holders are articulated together on common transverse axes.  4. Trolley according to any one of claims 1 to 3, characterized in that the bar-carrying cylinder has, in cross section, a circular shape comprising a support spout for the pressure bar.  5. Vertical slicer comprising a carriage according to any one of claims 1 to 4 and means for synchronizing the tilting movement of the assembly with the reciprocating movement of the table and the advance movement of the carriage.