FI86564C - Transport table for cutting strip material - Google Patents

Abstract

Improvements to a cutting table with vacuum grip, consisting of the provision of the means required to connect the vacuum to a conveyor (14) on which the strip material (12) to be cut with a numerically controlled machine is fixed. In particular, the conveyor (14) is of the type made up by a succession of tiles (48) connected to the links of two chains (50) (or group thereof) which are closed and which slip or run along guides and mesh with at least two toothed wheels (54) which provide the movement. On the upper face of the loop formed by the succession of tiles, a bridge (20) runs with supports and movement devices (30) of its own which provide it with the movement in - the same direction as the conveyor (14). - On this bridge (20), a carriage (22) moves with the tools for working the material (12). - In order to hold the strip material (12), a vacuum is applied in accordance with the subject of this invention, under the working surface, formed by the upper face of the conveyor (14).- The said vacuum is applied to each of the tiles (48) which are hermetic enclosures with outlets only on the outside faces of the loop created by the conveyor (14).

Description

1 86564

Conveyor table for cutting strip material

The invention relates to a conveyor table for a numerically controlled cutting machine for cutting a strip-holding strip material, which conveyor table comprises interconnected plates attached to chains and driven by a drive motor and consisting of brush mats forming an air-permeable cutting table 10 and the mats are fixed, and a vacuum system comprising a vacuum source, said tubes being part of the vacuum system and having holes in their upper surface for co-operation with the brush mats, and below the openings aligned and co-operating with openings in the upper surface of the main tube 15 wherein the tubes on which the bristle mats are attached are hermetically sealed at their ends by means of end portions and are placed at right angles to the main tube and the tubes have sealing means arranged between each pipe 20 to prevent the formation of vacuum leaks.

There are many patents relating to the cutting of textiles and the like on fixed tables, in which the substances are held in place under reduced pressure. Due to the sizes (large lengths) of the material to be cut, movable tables were developed that feed the material so that they function part by part, which prevents the cutting of sizes equal to or larger than the material to be cut. In this system, the structure of the vacuum holding means 30 cannot be as simple as in a fixed table. The problem of sealing the moving parts resulted in the transport table being completely enclosed in an airtight "drawer", which left the top open; once the fabric is in place, it is closed by an impermeable substance which does not allow air to pass through and which is normally discarded after the cutting blade has pierced it.

Applications for this technology can be found in Spanish U.S. Patent Nos. 520,922, 520,923 and 520,924 to Gerber Garment Technology Inc. or 5 Stumpf Patent No. 4,322,993. One disadvantage of these systems is that the drawer must be robust because the vacuum used and the relatively large areas cause very large forces (a few tons).

Another solution developed is an airtight chamber below the surface of the operating table 10, which communicates via valves with various parts, such as in Gerber's Spanish Patent No. 506,931. 15 seasonal equipment is working. This known method only partially solves the problem, because the area under vacuum, divided into parts, has to be made large enough to cover the surface area of the material, so as to ensure its retention despite the operation of the cutter, thus maintaining high loads.

Later developments led to the division of the vacuum area into several parts and the operating table became too complex, cf. U.S. Patents 4,485,712 and 4,528,878 to Gerber.

The present invention relates to a simple solution for the use of a vacuum, which does not develop large, sealed chambers or division into parts, which makes the structure very much simpler.

Conveyor table according to the invention is characterized::: 30 by the fact that the main pipe is a plastic, low friction support strip, which is arranged in the upper surface of the main pipe, and the rubber strips that are in contact with the plastic of the TU-kikaistaleen complement of the conveyor working surface of the interior of the hermetic seal.

Preferred embodiments of a conveyor table according to the invention are set out in the appended claims 2 and 3. The conveyor table plates are connected to loops of two chains (or groups of chains) which are closed and slid or run by guides and are connected to at least two gears. cause movement.

On the upper surface of the loop formed by successive slabs runs a bridge with its own supports and transfer devices which allow it to move in the same direction as the 10 conveyors. This bridge carries a wagon with the tools needed to cut the substance.

To secure the tape material, a vacuum is applied below the work surface formed by the upper surface of the conveyor. This vacuum is applied to each plate, which are hermetically sealed housings with outlets only on the surfaces outside the loop formed by the conveyor.

In the accompanying drawings: Figure 1 shows a cutting machine used in the technique of the present invention; Fig. 2 shows a view of a part of the transmission parts along the axis X-Y; Fig. 3 shows a schematic profile view of the subject of Fig. 1; Fig. 4 shows a view of a part of a moving table; Fig. 5 shows a view of a part in which a vacuum is applied to the cutting area; Fig. 6 shows a cross-sectional view of the moving tiles; Fig. 7 shows a perspective view of the plates and another model of the head seal; and Figure 8 shows a diagram of the general pressure distribution. Figure 1 shows a cutting machine 1 containing a po. an invention such as is commonly used in such work and is briefly described below.

4,86564

The conveyor 14 feeds a strip of tape material 12 from the spreading table 5. The cut strips 18 are removed in the area 16 and also at the adjacent part of the conveyor.

The shape of the section is obtained by moving the bridge 20 or the X carriage and the Y carriage 22. The control device 24 controls these movements and drives the motors of the X and Y carriages.

The carriage 22 has a cutting means suitable for the material to be treated, as shown in Fig. 2 and is guided by guides 26. This figure also shows the drive motor 10 and the belt which transmits the movement. There are three engines in this wagon; the blade drive motor, the one that aligns the blade in the lateral direction on the cutting line, and the sharpener motor.

The carriage on the X-axis is guided by guides 32 and its motor 34, which is fixed to the frame, moves the bridge by means of a belt 36.

The interaction between table movements and cutting movements, described in Applicant's ES Patent No. 541,826, is briefly described below.

20 The conveyor is divided into three parts, as shown in Fig. 3; to the feed area 38, the cutting area 40 and the collection area 42.

The substance is applied in advance to the table 5, where the compressed air holes facilitate the sliding of the substance in the direction of the cutting machine 25. After cutting strips that are completely in the cutting area, starting at X = 0 at the abscissa, the conveyor driven by the motor 44 can move along the smallest abscissa corresponding to the next strip to be cut and which was not completely inside the cutting window 40.

30 The previously cut ingredient is in the region 42, which continues to the collection table 16.

The strips furthest from the intersection area are assembled and, with the bridge close to the largest abscissa, those closest, for the reasons explained below.

The connections between the tables 16 and 5 with the conveyor 5 86564 sa are made by means of combs 46 which provide a smooth transition in feeding and collection.

Figure 4 shows the transport table. For clarity, it does not show the loading and unloading tables or the X-wagon drive-5 and controls.

The plate chain 48 is shown attached to a chain 50 which is guided over a suitable part and which is preferably plastic to remove friction and noise. The wheels 54 driven by the motor 44 move the chains in accordance with the commands and information given by the control device, which control device follows the procedure described above. The shaft-mounted optical encoder 56 continuously provides information on the exact location of the chain, so that by comparing these with the signal from the encoder included in the X-Vau-15's drive motor 34, the relative positions of the bridge and conveyor are known.

Figure 5 shows a part of the structure of the tiles 48 as well as the vacuum supply system which holds the substance to be treated in place under atmospheric pressure, which is the basic object of the invention.

These plates consist of a hollow tube 58 which is hermetically sealed at the ends by portions 60 and has a large opening 62 below and various holes in the upper surface which communicate with the bristle blocks or mats 64 25 which allow air to pass through.

Figure 6 shows part of the preferred connection between the pipe and the mats; in this system, the mats can be removed by taking out the end portion 60. The figure shows the drilled holes 59 and the base 61 which pass through the air.

These successive blocks form a work surface, which in this case is the surface through which the cutting blade can penetrate.

The tubes 66 are attached to the conveyor and, through suitable connections 35, communicate with the vacuum generated by the pump 68. Attached to the upper surface of the tube 66 is a strip of flux 70 of 86564 xlux having low friction and wear values. The tube 66 and strip 70 have wide openings 72 which supply vacuum through holes 62 in plates 48 which slide over the strip. When the chains 50 connected to the pipes 58 5 use slabs, the drilled holes 62 and 72 are always completely or partially in line so that the vacuum can be supplied; this is because the spacing of the holes 72 is less than their length, while their size is the same as in the plates of the holes 62.

10 the vacuum tubes 58 flows in the carpet 64 and to prevent leaks between the tiles used in seals 74. Similarly, to ensure the sealing strip 70 and the tube 58 is used between the rubber strips 76, which are complementary to the conveyor working surface of the interior of the air-tight seal 15 Tysta.

In another preferred embodiment, the drilled holes 72 are replaced by a continuous opening the length of which corresponds to the vacuum application area, so that there is never any obstacle to the movement of air in the holes 62 in this area.

20 The upper surface formed by the mats 64 is a support for the material to be cut. If it is not sufficiently impermeable, a disposable plastic can be used to seal this surface and the material or plastic and the material is held in place under atmospheric pressure.

The portions 60 have drilled holes 78 for securing the roofing plastic under reduced pressure, which prevents these portions 60 from entering the connections.

In another form of tile ends shown in Figure 7, portions 60 have been replaced with blocks 120, 30 of flexible material, which is also impermeable, e.g. In the previous model, this was the function of the seal 74 on the side of the part 60.

35 Depending on the length of the areas 38, 40 and 42 in Fig. 3, the length of the drilled part of the pipe 66 is fixed, i.e. the length 7 86564 at which the vacuum is applied to the slabs. Figure 8 shows how the pressures are applied and this will be explained qualitatively in the following.

The pump 68 generates a vacuum PO, part of which is lost in a line extending to the inlet side of the pipe 66. If a pressure P1 is obtained on this inlet side, the load is further lost on the way to the slabs, i.e. the pressure P2 at the mat is higher than the pressure P1. Since the adhesive agent 12 based on the pressures Pa - P2, the difference between, the pressure P2 10 must be as small as possible, so the loss must be as small as possible from the pump output side and a non-pressure P2 should be equal to the pressure PO, which is the lowest pressure in the entire circuit.

This pressure difference should be maximum in the cut-15 region 40 and in region 38 it should be large enough to support the fabric from the application table.

At parts A and B, where the loop begins to curve, there is an opening leading to the outside air, so the pressure P2 should gradually increase through the mat until it reaches 20 atmospheric pressure Pa.

The vacuum should be applied as far as possible to the region 38, but if the pressure in this region is P3, the necessary load loss Pa - P3 at high flows is achieved at the opening B, so that the pump impulse level 25 is not sufficient. Thus, the suction area tends to concentrate and be separated from the parts with open ends, so that a good difference Pa - P3 is achieved. This careful reduction, due to the length reached by the mat, ensures that the material is sufficiently fixed over such a large area that it can be moved.

In part A, the problem at the discharge head is not as great, here it is only necessary to take the precaution described above in the method of collecting from area 42, first collecting the strips closest to part A35 and when the cutting bridge is at end 40 are inside the collection area.

Claims (3)

A conveyor table (14) for a numerically controlled cutting machine (1) for cutting strip material (12) which is fastened with underpressure, said conveyor table comprising interconnecting plates (48), which are fixed in chains (50) and are driven by a drive motor (44) and which consist of brush mats (64) forming an air-permeable cutting table, and of tubes (58) to which the brush mats are attached and a suppression system comprising a vacuum source (68), wherein said tube ( 58) is part of the suppression system and their upper surface has heels (59) for cooperation with the brush mats, and below are openings (62) which are in line and cooperate with openings (72) in the upper surface of the main pipe (66), which main pipe is connected to the source of suppression, wherein the tubes (58) to which the brush mats are attached are at their ends hermetically sealed by gable parts (60) and are placed at right angles relative to the main tube (66) and in the tubes are arranged between each tube Sheet sealing means 20 (74, 76) which prevent the occurrence of vacuum leakage, characterized in that the main pipe (60) has a low friction plastic strip (70) which is arranged in the upper surface and rubber band of the main pipe (76). which are in contact with the plastic support strip to complicate the hermetic seal on the inside of the conveyor's working surface. 2. Transport table (14) according to claim 1, characterized in that the arrangement of the heel (72) in the main pipe (66) and in the support strip (70) of plastic is customary, in which as a hoist of the conveyor (14). This position is thus the heel and the heel (62) on the lower side of the tubes (58) belonging to the plates (48) in whole or in part in the same line, since the distance between the heels in the main tube (66) is less than their length and the length of the heel. in the tubes (58) also 35 is the same. 11 86564 Transport table (14) according to claims 1 or 2, characterized in that the tubes have been formed to receive the brush mats, so that after removing the gable parts (60), the brush mats can be removed from the tubes (58).