WO1995032897A1

WO1995032897A1 - Former for use in packaging machine and method of manufacturing same

Info

Publication number: WO1995032897A1
Application number: PCT/JP1995/001041
Authority: WO
Inventors: Masao Fukuda
Original assignee: Ishida Co., Ltd.
Priority date: 1994-05-30
Filing date: 1995-05-30
Publication date: 1995-12-07
Also published as: JPH07315313A; JP3546968B2

Abstract

A method of the invention comprising finding a quadratic expression obtained by multiplying a coefficient, which is determined depending upon a dimension of a bag, a quality of a package material and the like, as an expanded curve R for a joined portion on a ridgeline, inputting curve data as found into a forming apparatus to thereby form the expanded curve (R) of the ridgeline, where a sailor portion (6) and a tube portion (2) join to each other, as a continuous curve which will not generate wrinkles, and simultaneously inputting into the forming apparatus data, which include dimensions to be determined by the size of a bag, a shape of a longitudinal seal and the like, to thereby form a former of a desired size automatically and accurately.

Description

Description Formers used in packaging machines and their manufacturing methods

The present invention relates to a former used for a packaging machine and a method for manufacturing the former. Background art

In a bag making and packaging machine represented by a vertical type packaging machine, a former for bending a long packaging material into a cylindrical shape is used.

As shown in FIG. 10, this foamer is arranged so that the long packaging material s sent in a flat state follows the curved surface of the sailor part 6 and surrounds the tube part 1. The tube is bent at an acute angle from the ridge line 9 where the sailor section 6 and the tube section 1 are joined to the side of the tube section 1, and then bent into a cylindrical shape.

For this reason, the packaging material s that has been pushed upward along the upper surface of the sailor section 6 turns sharply on the ridgeline section 9, and the pull-down belt (not shown) and the packaged material inserted therein If the ridgeline 9 is not properly formed or has a slight unevenness and is not formed as a continuous curve, the process of passing through this portion As a result, the packaging material s becomes swelled, which causes inconveniences such as the formation of vertical thin thread streaks on the bag surface and impairing the appearance of the product.

For this reason, these types of formers are usually formed by mirror-making, and the ridges 9 are precisely shaped using a master mold. Long hours of work In addition to this, the manufacturing cost is unnecessarily high, and there is an inconvenience in that the compatibility is poor due to the unevenness of the shape of each foam.

In addition, this type of former must be aligned with the size of the bag to be molded, and the shape of the vertical seal is a fin seal type or a wrap seal type, and the position of the vertical seal is a standard type. The width and position of the part to be overlapped must be changed depending on whether the vertical seal is of the standard type or the reverse type, and the material and thickness of the packaging material s Depending on the size of the bag, the inclination angle of part 6 of the cella must be changed.

For 0, there is a problem that it is necessary to arrange a large number of formats according to the specification, and the cost required for this is not negligible.

Accordingly, the present invention provides a new packaging machine foamer capable of accurately and automatically manufacturing various types of formers conforming to specifications using a numerically controlled machine tool. The purpose is to do so.

5 Another object of the present invention is to make it easy to numerically analyze the development curve of the ridge joint when the sailor part and the tube part are developed, and that the rate of change of the tangent at the ridge joint is constant. An object of the present invention is to provide a packaging machine having a quadratic curve and a manufacturing method thereof.

Still another object of the present invention is to provide a ridge joint having a flat shape and the highest point of a tube ridge when a development curve of the ridge joint cannot be numerically analyzed. It is an object of the present invention to propose a method for manufacturing a former for a packaging machine, in which a distance between the ridge line and the lowest point is set as a constraint condition, and a curve that derives a constant change rate of the tangent line at the ridge line joint is obtained.

5 Disclosure of the invention

The present invention derives a curve such that the rate of change of the tangent at the ridge joint is constant. This curve is used as the development curve of the ridge joint between the cellar section and the tube section. A part of the sailor and the tube are cut out from a blank material, and these are bent, and the ridge joints are joined to form a uniform former. is there. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 shows a sailor and a tube cut out from a blank material by the method of the present invention, wherein (a) shows a sailor and (b) shows a tube.

Fig. 2 (a) and (b) are diagrams showing the basic forms of various formers. FIGS. 3 (a) to (c) are diagrams showing conditions for forming the ridge portion of the tube—a diagram, a ー diagram, and an η—ζ diagram.

5 Fig. 4 (a) and (b) are the ξ- and ξ-ζ diagrams showing the joint between the tube and the sailor.

Fig. 5 shows the vertical seal of the bag. ①-a, ①-b indicate its shape, ②-a, ②-b indicate its position, ③-a, ③-b indicate its direction. It is the figure respectively shown.

Ό Fig. 6 (a) to (c) are ξ-, ξ-ζ, and η-ζ diagrams showing the conditions for forming the ridge of the oblong former.

Fig. 7 (a) and (b) are a plan view and a perspective view showing the shape of the ridge joint between the tube and the cellar.

FIGS. 8 (a) and 8 (b) are explanatory diagrams each showing another example of the curve analysis method of the present invention.

Fig. 9 (a) and (b) are explanatory diagrams of the analysis method. FIG. 10 is a perspective view showing the entirety of the foamer used in the packaging machine. BEST MODE FOR CARRYING OUT THE INVENTION

Therefore, the embodiment illustrated below will be described.

First, based on Fig. 2 showing the basic shape of the former and Fig. 3 showing the molding conditions for the tube part 1 and sailor part 6, the packaging material sent onto the sailor part 6 The condition for bending this into a cylindrical shape along the inner peripheral surface of the tube part 1 without causing shear, etc., in other words, the ridge line Q where these both join has smooth continuity The following describes the molding conditions that allow the sheet to have a continuous differential coefficient.

〇 About tube part 1

The radius r of the tube part 1 is determined by the size of the bag to be molded. If the width of the bag (Fig. 5) is B,

Expressed as B π.

The distance の in the direction of the axis ζ of the tube 1 from the top 最上 to the bottom Α of the ridgeline Q is determined by the material and thickness of the packaging material.

Then, assuming that the inclination of Ο に対する with respect to the η axis is 0,

ξ = ΟΑ— P A 'c os 0

= 2 r (1-c 0 s 2 θ)

= r (1-c 0 s 2 Θ) (1)

7) = P Asin Θ

= 2 r «sin 6 'cos 0 = rsin2θ (2)

Also, ζ = f (6)

Represents ζ as a function of e.

Next, as a design condition to keep the tangent change rate of the point P on the ridge line constant, first, it is decomposed into vectors, 傾き — 傾き the inclination on the plane projection, and ζ — the inclination on the plane projection. ) 3, then d ζ ά ζ '(θ)

t a η = (4) d d θ d 2 r-s i n 2 Θ d Θ d ζ ά ζ 1 f '(Θ)

t a η β = (5) d 7? d Θ d η 2 c os 2 Θ d Θ

Becomes

On the other hand, assuming that the slope of the tangent at point P with respect to the −η plane is y, from the design conditions, d

(t a ny) = —constant

d θ, and integrating this as a constant a,

t a n y = a Θ (6)

However, it is assumed that 0 = 0 and tany = 0.

From the definition of solid angle, a η γ = (7)

+

tan α tan β From

Substituting equations (4) and (5) into

(θ) = 2 a r θ (9) When integrating as f (ο) = 0,

f (Θ) = a y Θ 2 (1 0) where π

Η (1 1)

2 so that a γ π

= Η

Four

Becomes.

4Η

(12) a =

γ π 2-. Substituting this into the expression (10) gives

4Η

f (Θ) = θ ² = ζ (13) Then, open and expand at A-A section and express it by coordinate transformation.

H

Z = Y: (14)

(π r), and if it is processed with a parabola, the rate of change of the inclination of the ridge line can be kept constant. By the way, the explanation above is for the case where the shape of the ξ-plane is a circle, and the calculation becomes complicated. However, this idea can be applied to an oval or elliptical shape.

Where — the shape of the ridge projected onto the ζ plane is obtained by substituting equation (1 3) into equation (1),

Differentiating f with ζ gives d ξ 1 π

= 2 's i η 2 θ

d ζ d θ d ζ 8 ΘΗ d θ π s i η 2 θ

(17)

2Η 2 θ Here, assuming 20−0, s i η 2 θ

0

2 From θ, d π

(18) ά ζ 2 θ → 0 2Η

Becomes

〇Sailor Club 6

As shown in FIG. 4, when the packaging material moves in the direction of the ζ axis from the central axis 点 of the sailor section 6 through the point 0, the distance passing through the surface of the sailor section 6 becomes longer as the packaging material shifts from the center.

The angle δ between the surface of the sailor section 6 and the ridgeline Q is given by

π π

ζ + t a η '(19)

2 2Η Experimentally, δ is l l ο °, that is,

0

A good result can be obtained with a value of about 8 δ =

8

Five Substituting into (14) gives π π

t a n ζ +

9 2Η Therefore, the height セ of the cellar part 6 up to the top Ο of the ridgeline Q is .π

Η =

2 t a n ζ +

9

Now, assuming that the angle p of a typical part of the cell 6 is π / 4, Η = 0.2 3 3 π2 r

As a result, a standardized former can be designed.

The projection curve of the ridge line Q onto the ξ- ζ plane is given by equation (1)

And the slope at point 0 is π ² Γ

2Η

The tilt at point 平行 is parallel to the ζ axis, and on the 7?

2Η π r Becomes

The slope of the ridgeline Q is

2 Η π π, which is expressed by a linear equation with respect to 0, and its change is constant and does not cause any shrinkage in the packaging material.

For the expansion curve R,

Η

Z = a 7J ² = Y ²

(π ΐ) ² and a quadratic curve for Υ. The coefficients H and r are determined according to the material and thickness of the packaging material or the size of the bag to be molded.

-As shown in Fig. 2 (a), the tube portion 1 is bent into a cylindrical shape, and a slightly overlapped portion 2 is formed on both side ends thereof. As shown in (b), it is formed as a flat part 3 that can be stretched by a pair of left and right vertical seal heaters facing each other. Naturally, these parts 2 and 3 differ depending on the seal specifications. . On the other hand, as shown in Fig. 5, the vertical seal part of the bag has a fin seal type and a wrap seal type as shown in Fig. 1 (a) and (1)-(b). It is also called a gasoline tension, and it is a type that the inner surfaces of both sides of the packaging material are glued together and folded to one side, and the wrap seal type is also called an envelope tension, and the wrap seal type is The type in which the inner surface is adhered to the surface on the other side, the width and position of the joint e differ.

In addition, as for the locational classification, as shown in ①-a and ②-b in the figure, There are two types, the standard type and the offset type.The standard type places the joint e at the center of the bag in the width direction. Either the edge f or the outer edge 緣 g is located in the center of the bag in the width direction. Depending on which type is used, the width position of the packaging material fed into the tube part 1 must be changed.

In addition, the standard type and the re-purse type shown in ③-1a and ③1b in the same figure as the directional classification are due to the difference in the folding direction after the palms are folded. Since the position of the side edge is different, it is necessary to change the position of the packaging material in the width direction during feeding.

Therefore, for the sailor section 6 and tube section 1 to be molded, the width of the overhangs provided on both sides or one side are determined by specifying the shape of the bag, the position of the joint, or the folding direction. Is done.

In this way, the quadratic expression of the expansion curve of the ridge joint of the sailor 6 and the tube 1 and the width of the overhang are determined, and the overall unfolding shape as shown by the solid line in Fig. 1 is determined. The NC machining program is automatically created using a CADZCAM system or the like, and machining of the developed machining shape can be easily performed by an NC laser machine.

To explain this in detail, the CAD / CAM system uses the quadratic equation of the expansion curve R that forms each joint between the sailor part 6 and the tube part 1 as the processing shape data.

H

Z = Y ²

(π ι) The processing shape determined by ² and the coefficient of the diameter r of the tube part 1 and the height H in the axis Z direction of the expansion curve R determined according to the bag size, packaging material, and thickness are input. . In addition, the dimensions of the width of the bag, which is twice the width of the bag, are input to the skirt 8 of the sailor 6 and the tube 4 of the tube 1 according to the size of the bag to be molded. The dimension of the overhang portion W having a width set according to the shape of the bag to be molded or the position and direction of the adhesive portion is added to one or both sides and input.

Then, when the data of the entire developed processing shape is input and the processing condition parameters such as the thickness and the material of the processing material are set, the NC processing program is automatically created by the CADZCAM system.

The NC machining program created in this way is

0 As shown in Fig. 1, the processing machine is indicated by arrows from the corner M of the skirt 8 of the sailor section 6 and from the corner N of the tube section 4 by the tube section 1 respectively. The cut tube part 1 is cut into a cylinder in a single stroke in the direction, while the cut tube part 1 is bent into a cylindrical shape, and a slight step is provided at the upper part of the development curve R to make the sailor part 6 The development curve R is brought into contact with each other, and the two are integrated by welding to complete the former. By the way, FIG. 6 shows an example of molding conditions for a former in which a tube is formed into an oval shape for molding a large bag, and the intermediate formula is omitted.

The radius of each of the arc portions at both ends of the oval shape is r, the distance between the arc portions is L, and the length of the tube axis direction Z from the highest point to the lowest point of the ridge line of the tube is Hi, Assuming that the axis in the radial direction of the tube is Y, the quadratic expression as the expansion curve to be input to the cutting means is

Becomes By the way, in the above description, when the sailor part 1 and the tube part 2 are deployed, the development curve of the joint where they are joined is a quadratic curve. In addition to the following curves, it is assumed that there are curves that are extremely difficult to perform numerical analysis, and curves that cannot be performed at all.

FIG. 7 to FIG. 9 show an embodiment of a foamer in which the development curve of the ridge joint is formed of such a curve, and a method of manufacturing the same. As shown in Fig. 7 (a), the expansion curve calculation method of this forma uses the plane shape 0 of the tube section 6 and the ridge line joint of the cellar part 2 as a circular or elliptical shape as shown in Fig. 7 (a). Set.

That is, in the case of a circle,

g (V) = | 2 + _η Ζ + _y Z = 0

In the case of an oval,

g (ζ, η) = f 2 / _a 2 + r, 2 / b2-l = 0

5 and then, as the constraint condition ②, consider the axis 厚み direction distance チューブ of the tube part 1 from the highest point O to the lowest point A of the ridgeline Q in consideration of the material and thickness of the packaging material.

At point f, f (0, 0, 0) = 0

At point A, f (ξ, 0, H) = 0

: Set to 0.

Then, as shown in FIGS. 7 (b) and 8 (a), a minute line segment at a certain point S on the three-dimensional curve defined by the ridge joint is defined as △ S, and the minute line segment ΔS Δ tanr / Δ S = —constant is the tangent change rate of the tangent at the ridge joint when the inclination angle is y

Determine 5 and determine the curve by trial and error.

That is, as shown in Fig. 8 (a), a minute line at a certain point So Δ すると where the slope of AS is A tany

a na

Mm

Δζ

= a η j3

Δ 7]

Δζ

= t a η 7

Αξ ² + Αη ²

And

Δ ξ ο ² + Δ η _D 2+ Δ ζ □ ≥ = Δ S ₀ 2.

g (Δ ξ □, Δ τ? □) = 0

Then,

The subsequent point Si is used as the initial value, and the slope of the minute line segment ASi at this point is

Ύ 1

ξ l2 + η ι2 + Δ V ζ ΐ2 = um S】 2

g (Δ ξ □ + Δ fl, Δ η □ + Δ τ? 1) = 0 constant

Ξ ΐ + ηΐ + ζ ΐ.

Further, 1 + V1 + ζ1 is set as an initial value, and the above operation is repeated by the same procedure until the point where η = 0.

Then, ζ = ΣΔ 求め at this time is obtained, and this is compared with the distance H up to the lowest point Α. If the difference is within the allowable error range, this professional Seth is the solution. On the other hand, at this time, ζ = ΣΔηη, as shown in Fig. 9 (b),

If ζ〉 Η, make tany 1-tany ₀ smaller,

If ζ <Η, increase t a n y l t a n y

Restart the calculation from the beginning.

When a solution is found in this way,

∑ A i → Y, ∑ Δ ζ i → Ζ

After determining the development data, and determining the development curve of the ridge joint of the cellar part 6 and the tube part 1 and the width dimension of the overhang part, the former is constructed by the processing method shown earlier. Go on. .

In this way, a curve is determined so that the rate of change of the tangent at the ridge joint is constant, and this is used as the development curve of the ridge joint between the sailor and the tube to be sent to the cellar. While sliding the wrapping material on the ridge line, the wrapping material can be smoothly formed along the inner peripheral surface of the tube portion and formed into a tubular shape without causing any shrinkage or the like.

Furthermore, by inputting the data on the expansion curve of the ridge joint obtained in this way and the data on the width of the overhang to the processing machine, it is possible to determine the compatibility of various sizes of formers. The molding can be performed easily and with high precision without having any skill. .

Claims

The scope of the claims

1. A former for use in a packaging machine, characterized in that a development curve of a ridge joint portion between a cellar portion and a tube portion is formed as a curve in which a tangent of the ridge line joint has a constant change rate.

2. The former according to claim 1, wherein the open curve is a quadratic curve.

3. The plane shape of the ridge joint and the distance between the highest point and the lowest point of the ridge of the tube are set as constraint conditions, and the rate of change of the tangent of the ridge joint is constant. The former used for the packaging machine according to claim 1, wherein the curve obtained in (1) is used as a development curve of a ridge joint portion between the sailor part and the tube part.

4. The expansion curve at the ridge joint between the sailor and the tube is a quadratic equation multiplied by a coefficient determined by the size of the bag and the material and thickness of the packaging material. Enter the width dimension as the sum of the width dimension of the bag and the dimension determined by the shape, position, and direction of the vertical seal, and then cut the sailor section and the tube section using cutting means. A method for producing a foam for use in a packaging machine, characterized by cutting out from a blank material and finally bending these members so that the above-mentioned ridge line joints are joined and integrated.

Ό 5. When the radius of the cylindrical tube is r, the height in the axial direction from the highest point to the lowest point of the ridge of the tube is Η, and the axis in the tangential direction of the tube is Υ, the cutting means is The quadratic equation as the expansion curve to be input to

Η

Ζ =

(η ι) ²

Five

A formal for use in a packaging machine according to claim 4, characterized in that: Manufacturing method

6. Make each radius of the arc at both ends of the ellipse! L, the distance between the arc portions; L, the height in the axial direction Z from the highest point to the lowest point of the ridge line of the tube portion; HI. The axis in the radial direction of the tube portion, Y , And the quadratic expression as the expansion curve to be input to the cutting means is

ζ = ½ ι + 1 +

^{(Π τ) 2 I \ π} r and to range Section 4 forma manufacturing method used for the packaging machine according to claim, characterized in that the.

7. With the planar shape of the ridge joint of the tuber and the tube, and the distance between the highest point and the lowest point of the ridge of the tube, as constraints, A curve such that the rate of change of the tangent line is constant is obtained by calculation as the expansion curve of the ridge line joint, and the obtained curve data is cut together with the width direction dimension data of the cellar part and the tube part. After the input to the means, the above-mentioned cellar part and tube part are cut out with a blank material using the cutting means, and finally, both are bent and the ridge line joint parts are joined to be integrated. A method of manufacturing a former for use in a packaging machine, characterized in that: