Cutting portal of an ultra-high pressure fluid jet cutting system

A cutting portal for an ultra-high-pressure fluid jet cutting system separates the longitudinal and transverse motion of the cutting head support. The portal includes two parallel plates with lightweight, honeycomb composite material between them. The cutting portal is moved transversely of its length longitudinally of the cutting table. A guide rail for the cutting head support is supported in the honeycomb material and extends along the length of the cutting portal, transversely to the motion of the cutting portal. Spaced apart bearing shafts are supported by bearing shells in the honeycomb material. A driven belt passes around the shafts and moves the cutting head support along the guide rail, which provides motion of the cutting jet in the transverse direction of the cutting table.

BACKGROUND OF THE INVENTION 
The present invention concerns the cutting portal of an ultra-high pressure 
fluid jet cutting system. To be able to cut material, the cutting jet of a 
fluid jet cutting system must be freely movable in all directions in a 
plane parallel to the cutting table. These two degrees of freedom are 
uncoupled so that one is associated with the cutting portal and the other 
is associated with the cutting-head support. 
The cutting portal is mounted to be displaceable in the longitudinal 
direction of the cutting table and carries the actual cutting device, 
namely the cutting-head support. The cutting head support is in turn 
mounted for displacement in the transverse direction of the cutting table. 
The entire weight of the cutting portal is an important parameter for 
establishing the average cutting speed on the system. For high speeds, 
smaller masses need be accelerated. 
SUMMARY OF THE INVENTION 
The object of the invention is to provide a cutting portal for an 
ultra-high pressure fluid jet cutting system which is of high stability, 
yet is of low weight. 
Another object of the invention is to have the bearing plates, which are 
required for the transverse displacement of the cutting head arranged 
thereon, be integral components. 
A further object of the invention is to be able to increase the cutting 
speed. 
According to the invention, the cutting portal for the ultra-high-pressure 
fluid jet cutting system obtains an increase in its cutting speed and is 
weight optimized through the cutting portal being formed of plates between 
which a honeycomb-structured, light-weight, composite material is 
disposed. Within this material are positioned the bearing shells for the 
spaced apart bearing shafts for the drive of the cutting head support. 
Further, a guide rail for guiding the movement of the cutting head support 
is also attached through couplings into the honeycomb material. The 
honeycomb material of the cutting portal therefore supports the major 
components. 
The bearing shells are formed by sleeves passing through the portal, 
through the honeycomb material and through the plates and define bearings 
for the shafts. A belt extends between the shafts to move the cutting head 
support along the guide rail and the cutting portal. The cutting portal 
itself is movable over the cutting table transverse to its long dimension. 
In that way, the cutting jet may be moved across the cutting table both 
longitudinally and transversely for effecting a cut. 
In a preferred arrangement, the bearing shells for the bearing shaft are 
comprised of two-piece sleeves, with one piece inserted into the honeycomb 
material from the respective opposite plate. Preferably, one piece of each 
sleeve is approximately twice as long as the other piece so that the total 
length of the bearing sleeve is divided into pieces with a length ratio of 
1 to 2. 
Other objects and features of the invention are explained in further detail 
with reference to the accompanying drawings.

DESCRIPTION OF A PREFERRED EMBODIMENT 
FIG. 1 shows an ultra-high-pressure fluid cutting system. 
The cutting portal 2 is mounted on the cutting table 1 on two racks (one of 
these is shown at 32a) so that it can be displaced in longitudinal 
direction. The cutting portal 2 carries the cutting-head support 3, which 
is arranged for transverse displacement on the cutting portal. Drive in 
both the longitudinal and the transverse directions is carried out via 
play-free transmissions and disk-armature motors. 
During a cutting pass, a pattern, which at times may be relatively 
complicated and may have numerous curves, must be followed. In order to 
achieve the highest average cutting speed of the system, the masses to be 
accelerated must be small. For this reason, the cutting portal 2 is 
comprised of two thin plates 4, 5 which are spaced apart from each other. 
The space between those plates is filled with a honeycomb-like composite 
material 6. Such a composite material is known as "honeycomb" and is used, 
for instance, in vehicles for air and space travel. In order to increase 
its stability, the cutting portal 2 advantageously has a trapezoidal 
shape, as seen in top view. A reinforcement in the form of a strip 21, 
also comprised of composite material, is applied along the Y axis. 
FIG. 2 is a section along the line A--A of FIG. 1. The shafts 7, 8 
necessary for the transverse displacement of the cutting head support 3 
are rotatably supported in bearing housings 22, 23 that are indirectly 
supported in the honeycomb structure 6 of the cutting portal 2. The 
bearing housings 22, 23 are pressed into bearing shells 11, 12. Those 
shells are assembled from two-piece sleeves 11a, 11b and 12a, 12b. Each 
two-piece sleeve 11a, 11b and 12a, 12b is preferably divided so that one 
piece is approximately twice the length of the other piece, so and the 
sleeve pieces of each sleeve have a length ratio of about 1 to 2. The 
sleeve pieces are installed from opposite respective sides or plates of 
the cutting portal. The sleeve pieces are firmly bonded to the honeycomb 
structure 6 by a plastic cement 13. The sleeve parts 11a, 11b and 12a, 12b 
are provided on their outer ends with radial collars 14a, 14b and 15a, 15b 
respectively, which lie on the plates 4 and 5 respectively. 
The bearing shells 11, 12 are inserted perpendicular to the plates 4, 5 and 
thus extend parallel to the honeycomb structure 6. 
The inside diameter d of the bearing shells 11, 12 must be of such size 
that flexural forces resulting from the drive do not lead to a deformation 
of the plates 4, 5. The drive shaft 7 is connected to the drive shaft 8 
via a toothed belt 25 (for clarity, not shown in FIG. 1) to which the 
cutting-head support 3 (not shown in FIG. 2) is fastened. Depending upon 
the direction of rotation of the toothed belt 25, the cutting-head holder 
3 is moved to the left or right in FIG. 2. The shaft 7 is arranged 
eccentrically in the bearing housing 22 so that the tension of the toothed 
belt 25 can be adjusted by it. 
The bearing housing 22 can have a plurality of passage openings (not shown 
in detail) which, without affecting the strength, help satisfy the need 
for a light construction. On the drive shaft 8 there is fastened a gear 26 
which is operatively connected via the toothed belt 27 to a disk-armature 
motor (not shown). 
Both shafts 7, 8 together with the parts surrounding them (shaft bearing 
10, bearing housings 22, 23) are advantageously arranged in the bearing 
shells 11, 12 so that, in case of need, the complete unit can be replaced 
without disassembling the cutting portal 2. 
FIG. 3 shows a partial section along the line B--B. The transverse 
displacement of the cutting-head support 3 takes place along a guide rail 
16 which is fastened laterally on the cutting portal 2. The cutting-head 
support 3 travels, via rollers 17, 17a fastened thereon, on the guide rail 
16 which is fastened by a plurality of screws 18 directly in the honeycomb 
structure 6 of the composite material, perpendicular to the course of the 
honeycomb. The screws 18 engage into threaded couplings 19. The couplings 
are inserted, parallel to the plates 4, 5, into the honeycomb structure 6 
and are bonded to the honeycomb by an epoxy resin 20. 
In order to assure a secure attachment it is important to provide in the 
side of the cutting portal 2, which in itself is not capable of bearing 
load, a plurality of holes of a larger diameter than the outside diameter 
of the threaded coupling 19 and to fill those holes with epoxy resin. A 
threaded coupling 19 is then introduced into each of the holes and is held 
fast until the epoxy resin has hardened. It is also conceivable to obtain 
a dependable attachment by filling the holes with plastic cement and, 
after that hardens, to cut threads coaxially to the original holes, into 
which threaded inserts (not shown in detail) can be screwed. 
Referring again to FIG. 2, in order to make certain that both sides of the 
cutting portal 2 are pushed exactly parallel to each other in the 
longitudinal direction over the supporting cutting table 1, there is 
arranged on the cutting portal 2 a compensating shaft 30, which is 
developed as a torsion shaft having ends which are provided with pinions 
31, 31a which engage in the racks 32, 32a arranged on the cutting table, 
as shown in the partial view of FIG. 2. 
As compared with previous cutting portals of structural steel, this one 
formed of composite material is lighter by more than a factor of ten, so 
that, with equivalent rapidity, substantially greater acceleration is 
obtained, and this results in a substantial shortening of the cutting time 
for the cutting of material. 
Although the present invention has been described in connection with a 
preferred embodiment thereof, many variations will now become apparent to 
those skilled in the art. It is preferred, therefore, that the present 
invention be limited not by the specific disclosure herein, but only by 
the appended claims.