LT6431B - Method of manufacturing a special cam of rotating forming table of a paste-like foodstuff packaging machine - Google Patents

Abstract

The invention relates to machines for packaging butter and other paste-like foodstuffs having rotating forming table revolvable by a spacial cam.Embodiments of the present method include the following steps:copying a part of motion trajectory of a reference packaging machine with exact coordinates of a reference cam by applying a reverse engineering method using a documentation of the reference packaging machine;taking into account the prevailed motion trajectory of relative elements roller and spacial cam - expressed by a projective correction factor calculable according to cosine theorem within ranges of angle of rotation 0?- 90? and 630?- 720?of the spacial cam;tracing out a full range motion curve of the reference cam;estimation the full range motion curve describing motion law which suits to Fourier series of fifth order;calculation of geometry of the spacial cam by using a multi-paradigm numerical computing environment for solving engineering tasks; manufacturing of a master cam and milling of the spacial cam by the master cam-controlled milling machine according to in advance generated a three-dimensional body by a special software package.

Description

The present invention relates to dispensing and packaging devices for butter, margarine and other pasty food products having a rotary forming table which is rotated by a spatial cam of special geometry.

Known packaging machines for butter, margarine, and the like are described, for example, in U.S. Patent Nos. 3,346,490 and 3,434,784, which have a rotatable forming table with 8 slots evenly spaced. The forming table is rotated from the central drive through complex kinematic circuits.

Also known as automatic paste packing machines for packing butter, margarine, meat, curd, edible fats, fresh cheese or sweet curd in briquettes and other paste products into aluminum foil, laminate or parchment paper. Such packing machines have been manufactured in Lithuania, Germany and CIS countries for many years.

Fasa AB, Lithuania, is currently manufacturing an ARM dosing and wrapping machine (see FASA butter / margarine filling and wrapping machine ARM with more different portion sizes.mpg, https://www.voutube.com/watch?v = WU-o Sef4vA., Published 7/01/2013, and Automatic Packaging Machine ARM, Instruction Manual, 2008), hereinafter in the description of the invention, an ARM packaging machine. The main components of this unit: main gear housing, briquette maker, rotary forming table, dosing box, briquette sealing device, conveyor, electrical control panel, etc. The ARM packing machine can perform the following functions: product loading, bottling, labeling of food packaging material and date, labeling and so on. The design of the unit ensures that all packing operations are carried out in a consistent circle. The main connecting link between the most important units of the machine is a pivoting forming table which performs technological operations related to the formation and packaging of the product. The rotary motion required for the forming table is provided by the spacer cam interacting with the tracker.

The spacer cam plays a very important role in the ARM packaging machine. The accuracy of the cam geometry determines the accuracy of all functions related to the packaging operation and the durability of the device. The technology of making a spacer cam includes forming a cam liner by copying a spacer cam that has already worked in the packing machine, making a copter based on the resulting cam liner, copying a cam, and sketchy finishing during assembly of the device. the spacer cam would work without vibration.

However, the technology used to make the spacer cam used in the packaging machine ARM is complex and does not allow for optimal cam geometry to facilitate functions related to packaging operations. Experimental studies have shown that the computed geometry of the copter does not correspond to the exact coordinates of the spatial motion of the cam and the actual conditions of its functioning in the packing machine, so the manufactured cam required additional locksmithing. Based on the analysis of the information contained in the technological cards of the components of the ARM-type packaging equipment manufactured by the company, an additional 4 hours were allocated for this locksmith operation. time. In addition, even after the manual finishing operation, the spacer cam did not always allow the packer to operate at the set speed. Deficiencies in the spatial cam geometry also shortened the durability of individual units. This required more frequent maintenance of the unit.

SUMMARY OF THE INVENTION The object of the present invention is to improve the production method of a rotary forming cam of a paste food packaging machine, which shortens the production time of the cam and increases its geometry accuracy, which improves the functioning and durability of the packaging machine.

According to the invention, this object is accomplished in a manner comprising the steps of:

copying, in reverse engineering, a portion of the motion path of the reference packer with exact coordinates of the reference spacer, whereby the motion portion is copied using documentation of the reference device including the drawing of the spacer and tables showing the radius dependence of the radius of the reference cam;

takes into account the prevailing movement trajectory of the interlocking table-follower and the space cam, expressed as a projection geometry correction factor that varies with the space-cam rotation, calculated by the cosine theorem in the space-cam rotation angles 0 ° - 90 ° and 630 ° - 720 ° ;

Prepare a full-range motion curve for the reference space cam;

determines a motion law describing the full range motion curve of a reference spatial cam which, based on experimental studies, corresponds to the Fourth order of the 5th order described below;

calculates a spatial cam geometry using multi-platform software for technical computation using Fourier 5 series;

Produces a cavity and mills the cavity with a 3D cam geometry using a Milling Duplicator, or Creates a 3D cam with a Numerically Controlled (NC) machine, after generating its spatial body by a parametric spatial design software package.

The invention is explained in more detail in the description based on the drawings, in which:

FIG. 1 shows a packing unit ARM forming table unit with a spacer cam.

FIG. Figure 2 shows the forming table, top view.

FIG. 3 - Mechanically machined reference spacer cam for the ARM packaging machine.

FIG. 4 is a full-range motion curve of a spatial cam restored by reverse engineering.

FIG. 5 is the full-range motion curve of a three-dimensional cam computed using the 5th order Fourier function line.

FIG. 6 - Space cam made using a numerically controlled (NC) machine tool.

FIG. 7 -. a spatial cam model designed with a parametric spatial design software package.

The life cycle of a packaging machine usually begins with the formation of the packaging material by the product packaging mechanism of the product packaging (not shown in the drawings). The box forming mechanism then forms a box (not shown in the drawings) and feeds it into a rotating forming table 1 (FIG. 1, FIG. 2) for performing the technological operations of packing and packaging the product and removing the manufactured briquettes. The forming table 1 has eight slots 2, which are fitted with pushers 3 with jacks 4 which rest on adjustable pins 5 and 6. The rotation of the forming table 1 is controlled by the space cam 7 (fig. 1, fig. 2) which, by turning the follower 8, rotates the carousel 9, which transmits the rotational motion further - the ball bearing in the housing cover 10 allows easy rotation of the major axis of the structure rigidly connected to the carousel 9. By rotation, the forming table 1 carries the previously formed box to the metering unit. The dispenser fills the box with a preset portion of the product. As the rotary table continues to rotate, the briquette of product 1 moves to the packing unit. When the edges are folded, the briquette socket 2 moves to the press (not shown in the drawings below), which finally compresses the briquette. The briquette then moves to the stripping mechanism and is fed to the tilting device which drops it onto the conveyor belt.

The spatial cam 7 allows for precise transformation of a constant rotational motion into a sliding one, and if this sliding motion is performed around a particular axis, a cyclic rotary motion is obtained. In order to properly describe the exact coordinates of the motion law of the spacer cam 7 obtained after the final machining (Fig. 3), the reverse engineering method is used. For this purpose, reference is made to the documentation of the reference packer ARM or other similar device, to the drawing of the reference spacer cam (not enclosed) and to the tables showing the radius dependence of the reference cam axial line a. In this way, a portion of the motion trajectory of the ARM device with exact spatial cam coordinates is copied.

In order to adapt the particular spatial cam coordinates for a given device to ensure smooth movement of the ARM cam 7 in conjunction with a pair-mounted tracker 8 rotating table 1, the prevailing trajectory of inter-element movement, i.e. The values of the projection geometry correction factor are calculated using the well-known cosine theorem known in mathematics, commonly used to find the sides of any triangle and / or ), knowing the two sides and the angle between them.

FIG. 4 shows the inverse engineering variations of the full range motion curve of the spatial cam, where 1 is the curve obtained without the correction factor and 2 is the curve with the correction factor whose influence is visible at the ends of this curve.

In order to graphically compare the existing spatial cam coordinates of the packing equipment, it is necessary to obtain a functional dependence of the packing machine which accurately describes the nature of the variation of said points, since the different coordinate pitch sizes in different documentation sources, i.e. one dossier contains data every 5 degrees, the other dossier contains data every 2 degrees. This requires the creation of a law that adequately describes (interpolates) the information available, regardless of how densely this information is represented in the documentation.

With a full-range spatial cam motion curve, a descriptive spatial cam motion law is derived based on Fourier series, which is used in practice to describe the deterministic oscillations of real sources of any form. To this end, a mathematical model was developed that describes the equations of motion law in the 3rd order, the 4th order, the 5th order Fourier and the nth order Fourier. The following equations of motion were used:

- 3rd order Fourier row f (x) = a0 + a1 * cos (x * w) + b1 * sin (x * w) + a2 * cos (2 * x * w) + b2 * * sin (2 * x * w) + a3 * cos (3 * x * w) + b3 * sin (3 * x * w) + c1;

- Fourth order Fourier row f (x) = a0 + a1 * cos (x * w) + b1 * sin (x * w) + a2 * cos (2 * x * w) + b2 * * sin (2 * x * w) + a3 * cos (3 * x * w) + b3 * sin (3 * x * w) + a4 * cos (4 * x * w) + b4 * sin (4 * x * w) + c1 ;

- 5th order Fourier row f (x) = aO + a1 * cos (x * w) + b1 * sin (x * w) + a2 * cos (2 * x * w) + b2 ** sin (2 * x * w) + a3 * cos (3 * x * w) + b 3 * sin (3 * x * w) + a4 * cos (4 * x * w) + b4 * sin (4 * x * w) + a5 * cos (5 * x * w) + b5 * sin (5 * x * w) + c1;

- nth order Fourier row f (x) = a * cos ((x * pi) / 180) + d + c1.

Here, aO, a1, a2, a3, b1, b3, b4, c1 denote stiffness and damping properties of stiffness and damping ratios.

The equations of motion law are described by multi-platform software such as MATLAB. This software is a technical computing environment for high-speed digital processing and visualization.

The calculations of the correspondence of the 3rd, 4th and 5th order Fourier functions with the available spatial cam coordinates were carried out.

Calculations with the derived dependence of the 3rd order Fourier function model on the given spatial cam coordinates showed a difference exceeding the permissible tolerance limit of 0.04 mm, i.e. amounted to 0.65 mm.

For the 4th order Fourier function, a difference exceeding the tolerance limit of 0.04 mm was also detected.

Using the 5th order Fourier dependence of the mathematical model and the interpolated points fit within the tolerance.

Calculations for matching the Fourier Fourth order or cosine function with the available spatial cam coordinates showed even worse results than for the 3rd and 4th order Fourier series, which are not discussed in further detail.

having evaluated the resulting calculations to calculate the spatial cam geometry, the 5th order Fourier row was selected. The resulting interpolation coefficients - radius length of the spatial cam axis relative to the cam angle of rotation (a) are given in Table 1 (fragment shown):

Table 1. Radius of the spatial cam axis line as a function of cam angle a.

a, ° R, mm a, ° R, mm a, R, mm a, R, mm 0.00 0.000 185.00 183,688 365.00 183,861 545.00 367.375 5.00 0.174 190.00 183,688 370.00 184,444 550.00 367.375 10.00 0.757 195.00 183,688 375.00 185,500 555.00 367.375 70.00 55,780 255.00 183,688 435.00 248,076 615.00 367.375 75.00 64,389 260.00 183,688 440.00 257,040 620.00 367.375 80.00 73,352 265.00 183,688 445.00 266,247 625.00 367.375 85.00 82,560 270.00 183,688 450.00 275,578 630.00 367.375 90.00 91.891 275.00 183,688 455.00 284,908 635.00 367.375 95.00 101,220 280.00 183,688 460.00 294,112 640.00 367.375 100.00 110,425 285.00 183,688 465.00 303,071 645.00 367.375 105.00 119,383 290.00 183,688 470.00 311,673 650.00 367.375 160.00 180,301 345.00 183,688 525.00 365,574 705.00 367.375 165.00 181,887 350.00 183,688 530.00 366,625 710.00 367.375 170.00 182,937 355.00 183,688 535.00 367.204 715.00 367.375 175.00 183,516 360.00 183,688 540.00 367.375 720.00 367.375 180.00 183,688

FIG. 5 shows the full-range motion curve of a three-dimensional squat computed using the 5th order Fourier function line. The interpolation coefficients given in Table 1 for the angle of rotation of the spatial cam within a range of 0 to 180 ° correspond to the curved part of the trajectory of cam movement close to the sine law; in the range 180 - 360 °, the linear portion of the cam trajectory; 360 - 540 ° - curved portion of the trajectory; 540 - 650 ° straight line; 650 - 720 ° - curved portion of the trajectory.

Using a mathematical law (5th order Fourier function line) that accurately describes the motion of the packing machine ARM spacer, the geometry of the spacer cam is calculated, and the HRF 500 produces a spacer cam copter and a cam itself.

With the geometry of the packing machine ARM space cam with motion co-ordinate motion copier, the space cam (Fig. 6) can also be manufactured by a numerically controlled (NC) machine after having created its spatial body (Fig. 7 in a parametric spatial design such as SolidVVorks software package.

Claims (8)

1. A method for manufacturing a rotary table spacer for a paste food packaging machine, comprising copying a spacer in the packing machine, making a rotary cam and milling a cam, other than by reverse engineering to copy the motion trajectories of the reference packaging machine takes into account the prevailing motion trajectory of the intercommunication element tracker and the space cam, expressed as a projection geometry correction coefficient, varying with respect to the rotation angle of the cam, draws a motion curve for the entire range of the reference space cam, determines the following curve , which calculates the space cam geometry, and then produces the copyrights and mills the space cam according to the calculated space cam geometry. 2. The method of manufacturing a spacer cam according to claim 1, wherein the movement portion of the reference packing device is copied using the documentation of the machine, which includes a drawing of the reference spacer cam and tables showing the radius of the reference cam axis relative to the cam rotation angle. 3. The method of producing a three-dimensional cam according to claim 1, characterized in that the projection geometry correction factor is calculated in the range of rotation of the three-dimensional cam between 0 ° and 90 ° and 630 ° - 720 °. 4. The method of producing a three-dimensional cam according to claim 3, characterized in that the projection geometry correction factor is calculated by the cosine theorem. 5. The method of producing a spatial cam according to claim 1, characterized in that the motion law equation describing the full range motion curve of the reference spatial cam is a 5th order Fourier row f (x) = a0 + a1 * cos (x * w) + b1 *. sin (x * w) + a2 * cos (2 * x * w) + b2 ** sin (2 * x * w) + a3 * cos (3 * x * w) + b3 * sin (3 * x * w) ) + a4 * cos (4 * x * w) + b4 * sin (4 * x * w) + a5 * cos (5 * x * w) + b5 * sin (5 * x * w) + c1 where aO , a1, a2, a3, b1, b3, b4, c1 - denoting stiffness and damping properties stiffness and damping ratios. 6. The method of manufacturing a three-dimensional cam according to claim 5, characterized in that the Fourth order of the 5th order is described by multi-platform software. A method of manufacturing a three-dimensional cam according to any one of the preceding claims, characterized in that the three-dimensional cam and its copier are produced by the HRF 500 milling machine. 8. The method of manufacturing a three-dimensional cam according to claims 1-6, characterized in that the three-dimensional cam is manufactured by means of a numerically controlled machine, after the creation of its three-dimensional body by a parametric spatial design software package.