CN102294823B - Determining method of welding condition - Google Patents

Abstract

The invention provides a determining method of appropriate welding condition at the time of welding a pair of resin formed products by means of a vibration welding method. The invention takes the difference between the fusion area (S1) of one resin formed product and the fusion area (S2) of another resin formed product into consideration, wherein S1 is no more than S2, and also takes an absorption energy absorbed by the other resin formed product in the heat generated by friction during the vibration welding into consideration. Specifically speaking, the welding condition is determined based on relation between the welding strength of the welding part and the absorption energy of the other resin formed product.

Description

Definite method of welding condition

Technical field

The present invention relates to a kind of definite method of the welding condition when utilizing a pair of resin forming product of vibration welded method welding.

Background technology

The method engaging each other as the resin molded body that makes to be formed by thermoplastic resin, except using the method linking with part (bolt, Screw, fixture etc.), bonding agent, it is also known for the burning-on methods such as hot plate burning-on method, vibration welded method, ultrasonic fusing method, laser welding method.

Utilize a pair of resin forming product of vibration welded method welding to be undertaken by for example following method.First, fix a resin forming product, then, overlapping another resin forming product, last in the above, on one side another resin forming product is pressurizeed, apply vibration on one side.Utilize the frictional energy of generation of vibration to make near the melting of the predetermined end face of welding, and make puddle each other overlapping, thus a pair of resin forming product of welding (with reference to patent documentation 1).According to the vibration welded method of utilizing frictional energy, owing to can making at short notice resin forming product melting, the therefore a pair of resin forming product of welding at short notice.That is, vibration welded method is the good welding process of productivity ratio of welding product.

Thereby, utilize the method for a pair of resin forming product of vibration welded method welding to be used in by automobile in the manufacturing process with the various kinds of resin goods centered by the manufacturing process of part.

But due to (welding condition) differences such as condition when a pair of resin forming product of welding, the intensity of weld portion is also different.Preferably the intensity of weld portion is stronger.Therefore, wish a pair of resin forming product of welding under the welding condition of intensity grow that makes weld portion.

But, due to for making the suitable welding condition of a pair of resin forming product welding be subject to the impact of the many factors such as kind, heating condition of resin, so present situation is to determine welding condition by experience.

Patent documentation 1: TOHKEMY 2005-319613 communique

Summary of the invention

The present invention completes in order to address the above problem, and its object is to provide a kind of definite method of easily determining suitable welding condition when utilizing a pair of resin forming product of vibration welded method welding.

In order to address the above problem, the inventor has carried out wholwe-hearted research repeatedly.Its result, finds the melting area (S of the resin forming product that the frictional energy by Elastic Vibration causes ₁) with the melting area (S of another resin forming product ₂) poor (S ₁≤ S ₂) and fricative heat during Elastic Vibration welding in, the energy that absorbed by another resin forming product, can address the above problem, thereby complete the present invention.Specifically, the invention provides definite method of following welding condition.

(1) a kind of definite method of welding condition, it is for determining the welding condition when the production welding product by this way, that is: the parallel direction of bearing surface forming along abutting against each other with by the predetermined end face of welding respectively with a pair of resin forming product of the predetermined end face of welding, apply the plus-pressure of the direction vertical with above-mentioned bearing surface on one side, make at least one resin forming product vibration on one side, thereby a pair of resin forming product of welding, wherein

When the melting area of the predetermined end face of welding of establishing a resin forming product during in welding is S ₁, the melting area of the predetermined end face of welding when welding of establishing another resin forming product be S ₂time, the constant definition that following formula (I) is represented is α,

[formula 1]

$\mathrm{\α}=\frac{2\×S_1}{S_1+S_2}\·\·\·\left(I\right)$

(establishing α≤1 in formula (I))

When if the vibration velocity during vibration of above-mentioned at least one resin forming product be V, to establish shear rate be V _sh, due to above-mentioned vibration melting the viscosity of resin while being η, the Q that following formula (II) is represented is defined as the caloric value that time per unit, per unit area produce on above-mentioned bearing surface,

[formula 2]

Q＝V _sh×η×V …(II)

If for considering that the constant of energy above-mentioned caloric value, that absorbed by above-mentioned another resin forming product is A, the E that following formula (III) is represented _sbe defined as and be supplied to supply energy above-mentioned another resin forming product side, time per unit, per unit area,

[formula 3]

E _s＝A×α×Q …(III)

Between a resin forming product before establishing welding and another resin forming product, along between the distance that applies above-mentioned stressed direction and the resin forming product after welding and another resin forming product, along the difference that applies the distance of above-mentioned stressed direction be L, when establishing weld time and being T, by the E of following formula (IV) expression _abe defined as the absorption energy of the per unit volume of being received by above-mentioned another resin forming product side draught,

[formula 4]

$E_a=E_s\×T\×\frac{1}{L/2}\·\·\·\left(\mathrm{IV}\right)$

Heat seal strength based on weld portion and absorption ENERGY E _adependency relation determine welding condition.

(2) according to definite method of the welding condition (1) described, the method is following operation, that is,

By following formula (V), represent above-mentioned weld time T,

[formula 5]

$T=\frac{B\×L}{{\left(Q\right)}^m\×{\left(P\right)}^n}\·\·\·\left(V\right)$

(B, the m in formula (V), n are constant)

Endergonic scope (E while determining that based on above-mentioned dependency relation heat seal strength becomes large _aL≤ E _a≤ E _aH),

[formula 6]

$E_{\mathrm{aL}}=2\×\frac{A\×B\×\mathrm{\α}}{{\left(Q\right)}^{m-1}\×{\left(P\right)}^n}\·\·\·\left(\mathrm{IV}\right)\text{'}$

[formula 7]

$E_{\mathrm{aH}}=2\×\frac{A\×B\×\mathrm{\α}}{{\left(Q\right)}^{m-1}\×{\left(P\right)}^n}\·\·\·\left(\mathrm{IV}\right)\text{'}\text{'}$

Based on by E _aLthe formula (IV) of the above-mentioned formula of substitution (IV) gained ' and by E _aHthe formula (IV) of the above-mentioned formula of substitution (IV) gained " determine welding condition.

(3) according to definite method of (1) or (2) described welding condition, wherein, dependency relation when above-mentioned dependency relation has the maximum of heat seal strength.

(4) according to definite method of the welding condition described in any one in (1) to (3), wherein, it is that resin is main component that the contained resinous principle of above-mentioned a pair of resin forming product all be take polyphenylene sulfide, and above-mentioned A is 0.28～0.38, above-mentioned m is 2, and said n is 1.

(5) according to definite method of the welding condition described in any one in (1) to (4), wherein, the method comprises following operation: based on above-mentioned absorption ENERGY E _aset endergonic scope (the Δ E of heat seal strength when large with the relation of heat seal strength _a(E _aLto E _aHscope)); A ' when calculating temperature that derived by this increasing extent of temperature, the above-mentioned resin when welding and becoming melting point, this increasing extent of temperature is to use following formula (v) by E _aLconstant times E _aLdensity, the specific heat meter of the resin of * A ', formation resin forming product are calculated; A when calculating temperature that derived by increasing extent of temperature, the above-mentioned resin when welding and becoming thermal decomposition point ", this increasing extent of temperature is to use following formula (v) by E _aHconstant times E _aH* A ", the density, the specific heat meter that form the resin of resin forming product calculate; And at the A ' deriving to A " scope in select constant A arbitrarily.

[formula 8]

(specific heat in formula (v), density are for forming specific heat and the density of the resin of resin forming product)

According to the present invention, when utilizing a pair of resin forming product of vibration welded method welding, the welding condition (suitable welding condition) when the heat seal strength that can easily determine weld portion becomes large.

Accompanying drawing explanation

(a) of Fig. 1 is the figure that has schematically shown the side section of the 1st resin forming product, (b) be the figure that has schematically shown the bottom surface of the 1st resin forming product, (c) be the figure that has schematically shown the side section of the 2nd resin forming product, (d) be the figure that has schematically shown the upper surface of the 2nd resin forming product;

Fig. 2 means the schematic diagram of side section of the summary process of vibration welded, (a) mean and make the figure of a pair of resin forming product in butt state, (b) mean near the melting predetermined end face of welding of resin forming product the figure of state, (c) mean welding figure midway, (d) mean the figure of welding product;

Fig. 3 means the schematic diagram of the situation of rail mounted (orbital) vibration, (a)～and (d) be the figure that schematically shows bearing surface G situation of 45 ° of every movements on the predetermined end face 111 of welding;

Fig. 4 means the enlarged drawing in the banded region in a narrow margin that coverlet chain-dotted line R, R clip, (a)～and (d) be respectively the enlarged drawing of Fig. 3 (a)～(d);

Fig. 5 is the enlarged drawing of side section of part that schematically shows the welding of the 1st resin forming product and the 2nd resin forming product, (a)～and (c) be respectively (a), (c) of Fig. 2, the enlarged drawing of (d);

Fig. 6 means the figure of heat seal strength and endergonic dependency relation, (a) means by the figure of 3 different absorption energy of welding conditions derivation and the relation of heat seal strength, (b) means that heat seal strength has the figure of peaked dependency relation;

Fig. 7 means the figure of the dependency relation of weld time and heat seal strength;

Fig. 8 means the 1st resin forming product of use in an embodiment and the figure of the 2nd resin forming product;

Fig. 9 is for the figure of the measuring method of heat seal strength is described;

Figure 10 means the heat seal strength of being derived by embodiment and the figure of endergonic dependency relation;

Figure 11 means the figure of the relation of heat seal strength and weld time;

Figure 12 means the figure of the chart of relational expression (vi).

The specific embodiment

Embodiments of the present invention are below described, but the present invention is not limited to following embodiment.

definite method of welding condition

The present invention is definite method of the welding condition when utilizing a pair of resin forming product of vibration welded method welding.

Specifically, the present invention includes following operation:

When the melting area of the predetermined end face of welding of establishing a resin forming product during in welding is S ₁, the melting area of the predetermined end face of welding when welding of establishing another resin forming product be S ₂time, according to above-mentioned formula (I) derived constant α (following or be called " the first operation ").

The parallel direction of bearing surface forming along abutting against each other with by the predetermined end face of the welding of a pair of resin forming product, apply the plus-pressure with above-mentioned bearing surface vertical direction on one side, make on one side at least one resin forming product vibration, the caloric value Q producing while deriving vibration according to above-mentioned formula (II) (following or be called " the second operation ").

According to above-mentioned caloric value Q, above-mentioned constant alpha, above-mentioned formula (III), derive and be fed into supply ENERGY E above-mentioned another resin forming product side, time per unit, per unit area _s(following or be called " the 3rd operation ").

When establish between a resin forming product before and after engaging and another resin forming product, along the difference that applies the distance of above-mentioned stressed direction, be L, establish the needed time of welding while being T, from above-mentioned formula (IV), derive by above-mentioned another resin forming product side draught absorption ENERGY E that receive, per unit volume _a(following or be called " the 4th operation ").

Derive the heat seal strength of weld portion and endergonic dependency relation (following or be called " the 5th operation ").

Based on above-mentioned dependency relation, determine the operation (following or be called " the 6th operation ") of welding condition.

Melting area (the S of the resin forming product that in the present invention, the frictional energy of Elastic Vibration causes ₁) with the melting area (S of another resin forming product ₂, S ₂>=S ₁) poor, and, the energy being absorbed by another resin forming product in the heat that the friction while considering due to welding produces.Even welding condition is changed into different conditions, the above-mentioned endergonic scope when heat seal strength of weld portion becomes large is also basic identical.Thereby, even if change welding condition, as long as the suitable endergonic scope based on having pre-determined is determined welding condition, just can easily obtain suitable welding condition.

Fig. 1 has represented the resin forming product using in the present embodiment.(a) of Fig. 1 is the figure that has schematically shown the side section of the 1st resin forming product, (b) be the figure that has schematically shown the bottom surface of the 1st resin forming product, (c) of Fig. 1 is the figure that has schematically shown the side section of the 2nd resin forming product, (d) is the figure that has schematically shown the upper surface of the 2nd resin forming product.The situation of the welding product that the 1st resin forming product 10 as shown in Figure 1 of vibration welded method manufacture that utilizes rail mounted vibration and the 2nd resin forming product 11 form of take is example, and each operation of the present invention is described in further detail.

Before describing each operation in detail, the situation of utilizing vibration welded method welding the 1st resin forming product 10 and the 2nd resin forming product 11 is described.The 1st resin forming product 10 shown in Fig. 1 (b) has the predetermined end face 101 of welding of ring-type.In addition, the 2nd resin forming product 11 shown in Fig. 1 (d) has the predetermined end face 111 of welding of ring-type.

First, use Fig. 2 that the summary situation of a pair of resin forming product of welding is described.Fig. 2 means the schematic diagram of side section of the summary process of vibration welded.As shown in Fig. 2 (a), the predetermined end face 101,111 of welding abuts against each other butt and forms bearing surface (following or be called " bearing surface G ").Bearing surface G is applied to plus-pressure P on one side, Yi Bian make the 1st resin forming product 10 vibrations, and make bearing surface G produce heat.Under the effect of this heat, near the predetermined end face 101,111 of welding of the 1st resin forming product 10, the 2nd resin forming product 11, as shown in Fig. 2 (b), form melting layer (the dot pattern part in Fig. 2 (b)).And if the oscillating movement of the 1st resin forming product 10 is proceeded,, as shown in Fig. 2 (c), melting layer is collapsed by pressure, the 1st resin forming product 10 is trapped in the 2nd resin forming product 11 simultaneously.Then, pressed the melting layer collapsing to be discharged from as burr.Between the 1st resin forming product 10 before and after engaging and the 2nd resin forming product 11, while becoming specific length along the difference of the distance of the direction of plus-pressure P, stop above-mentioned oscillating movement.Afterwards, in melting resin solidification before, adjust the position of the 1st resin forming product 10.After the resin of melting is cooling and curing, complete welding product 1 (Fig. 2 (d)).

Then, describe the situation of a pair of resin forming product of welding in detail.

First, describe the change procedure of Fig. 2 (a) to Fig. 2 (b) in detail.As mentioned above, the predetermined end face 111 of welding of the predetermined end face 101 of the welding of the 1st resin forming product 10 and the 2nd resin forming product 11 abuts against each other butt and forms bearing surface G.Afterwards, the direction shown in the blank arrow of an edge Fig. 2 (a) applies plus-pressure P, Yi Bian make the 1st resin forming product rail mounted vibration.The meaning of rail mounted vibration refers to, and makes under the predetermined end face 101,111 of welding state against each other, and the 1st resin forming product 10 draws with the direction along parallel with low junction G the vibration that round mode is moved.Use Fig. 3 to illustrate.

Fig. 3 means the schematic diagram of the situation of rail mounted vibration, (a)～and (d) be the situation that schematically shows bearing surface G 45 ° of every movements on the predetermined end face 111 of welding.And, also represent together the schematic diagram of XX ' section.As shown in Figure 3, to draw the move upper motion of double dot dash line P in the drawings of center O of the bearing surface G that refers to ring-type of round mode.If frequency (number of times that center O is rotated in 1 second on double dot dash line P) is f.Known according to the schematic diagram of XX ' section, if observe above-mentioned rail mounted vibration from the section vertical with bearing surface G, observe the reciprocating motion on straight line.

Take the banded region in a narrow margin that coverlet chain-dotted line R, R clip here, is object.The enlarged drawing that represents the banded region in a narrow margin that coverlet chain-dotted line R, R clip in Fig. 4.(a) of Fig. 4～(d) is respectively the enlarged drawing of Fig. 3 (a)～(d).In this region, rail mounted vibration, as shown in Fig. 4 (a)～(d), can be similar to the reciprocating motion of the linearity of rectangle (the hatching portion in Fig. 4).Rectangular length is the length Y between single-point line R, R _s, wide be the width X of ring of the bearing surface of ring-type _s.Below, with this rectangular motion explanation rail mounted vibration.If the rectangular center in the reciprocating direction of motion (directions X) is the X shown in Fig. 4 ₁, X ₂, X ₃, X ₄, reciprocating amplitude Δ X is (X ₃-X ₁), the diameter of the circle that the length of this amplitude represents with double dot dash line P (Fig. 3 (a)) is identical.

By this, move back and forth, bearing surface G is supplied with to heat.The integral body of the predetermined end face 101 of welding has been supplied to heat, predetermined end face 101 meltings of resin autogenous welding and form melting layer.About the predetermined end face 101 of welding, can learn according to Fig. 4 (a), (c), the above-mentioned rectangular part of bearing surface G is at (the Δ X+X of the predetermined end face 111 of welding _s) * Y _sscope in move back and forth.Thereby, (Δ X+X _s) * Y _sscope be supplied to heat, and this scope molten resin certainly, forms melting layer.

The variation of then, (b) of key diagram 2～(d).

Fig. 5 is the enlarged drawing of side section that schematically shows the weld of the 1st resin forming product 10 and the 2nd resin forming product 11.(a) of Fig. 5～(c) is respectively (a), (c) of Fig. 2, the enlarged drawing of (d).

The pressurized power P of melting layer shown in Fig. 5 (a) presses and collapses.If melting layer is collapsed and produces burr as shown in Fig. 5 (b) by pressure.In addition,, when melting layer is collapsed by pressure, the 1st resin forming product 10 is absorbed in along the direction of plus-pressure P.The result of this variation, becomes the state of Fig. 5 (b) from the state of Fig. 5 (a).

In (b) of Fig. 5, represented between the 1st resin forming product 10 and the 2nd resin forming product 11, along the difference of distance that applies the direction (Z direction) of plus-pressure P, be the state of Δ Z.The 1st resin forming product carries out rail mounted vibration until the poor Δ Z of above-mentioned distance reaches desired value L (or approach L value).In addition, even if melting layer is collapsed by pressure, because oscillating movement is proceeded, so the length of melting layer thickness is almost constant.

When Δ Z reaches L, rail mounted vibration stops, in melting resin solidification before, the 1st resin forming product is moved to target location.Afterwards, by making resin solidification, and as shown in Fig. 5 (c), make the 1st resin forming product 10 and the 2nd resin forming product 11 weldings.

Below describe each operation of definite method of welding condition of the present invention in detail.In the following description, use the oscillating movement of the 1st resin forming product in the region in a narrow margin shown in Fig. 4.In addition, establish the length Y between Q, Q _sfor unit length.

the first operation

The first operation is as described below: when the melting area of the predetermined end face of welding of establishing a resin forming product during in welding is S ₁, the melting area of the predetermined end face of welding when welding of establishing another resin forming product be S ₂time, from following formula (I) derived constant α.Here, establishing " resin forming product " is the 1st resin forming product 10, and establishing " another resin forming product " is the 2nd resin forming product 11.

[formula 9]

$\mathrm{\α}=\frac{2\×S_1}{S_1+S_2}\·\·\·\left(I\right)$

(establishing α≤1 in formula (I))

As mentioned above, integrally fused due to the predetermined end face 101 of welding, the banded region in a narrow margin that coverlet chain-dotted line R, R clip if therefore take is object, S ₁for X _s* Y _s.In addition S, ₂for (Δ X+X _s) * Y _s.Thereby, α=2 * X _s/ (Δ X+2 * X _s).

the second operation

The second operation is as described below: an edge abuts against each other with by the predetermined end face 101,111 of the welding of a pair of resin forming product 10,11 and the parallel direction of bearing surface G that forms applies the plus-pressure of the direction vertical with above-mentioned bearing surface G to above-mentioned bearing surface G, make at least one resin forming product (being the 1st resin forming product 10 in the present embodiment) vibration on one side, derive the caloric value Q that above-mentioned bearing surface G produces.

In the second operation, under the effect of shearing, make bearing surface G produce heat.Thereby, can utilize following method according to derive the heat that bearing surface G is produced due to shearing such as shear stress, displacement etc.

Vibration velocity when establishing vibration is that V, shear rate are V _sh, when the viscosity of the resin of melting is η due to this vibration, according to following formula (II), derive the caloric value Q that time per unit, per unit area produce at above-mentioned bearing surface.Shear rate V _sh* viscosities il is shear stress, is multiplied by the amount of movement (vibration velocity V) of time per unit with shear stress, can easily derive the energy (heat) that oscillating movement produces.Below, describe the method that derives caloric value Q according to following formula (II) in detail.

[formula 10]

Q＝V _sh×η×V …(II)

First, vibration velocity V is described.Can adopt for example following mode to derive vibration velocity V.

As mentioned above, the 1st resin forming product 10 moves on double dot dash line P with frequency f.Thereby, can represent vibration velocity V by following formula (i).

[formula 11]

V＝ΔX×π×f …(i)

(π in formula (i) is pi)

Then, shear rate V is described _sh.Can adopt for example following mode to derive shear rate V _sh.

Can by following formula (ii), represent shear rate V according to the thickness of melting layer, vibration velocity V _sh.

[formula 12]

In addition, such as by welding product decomposition having completed etc., can obtain simply melting layer thickness by autogenous welding vestige.

Then, viscosities il is described.When viscosities il is unknown value, can adopt for example following mode to derive.

Viscosities il be melting the viscosity of resin.The viscosity of resin changes according to the difference of shear rate, temperature.First, the method for determining temperature is described.

Here, viscosities il be resin due to the oscillating movement of the 1st resin forming product viscosity during melting.If the melting layer of the something in the resin of having considered in melting keeps shape to a certain degree etc., think the temperature of the resin in the melting layer scope in the melting point of resin (Tm)～melting point (Tm)+30 roughly ℃.Thereby said temperature is as long as adopt the arbitrary temp in this narrow temperature range.

Then, by actual measurement, obtain relation at the above-mentioned temperature of having determined, viscosities il and shear rate, and determine viscosity based on its result.For example,, if the relation of actual measurement several times viscosities il and shear rate, by using the formula of Cross-WLF to carry out matching (fitting), can derive the relational expression of viscosities il and shear rate.By the shear rate V of above-mentioned derivation _shin the shear rate of the relational expression that substitution is derived, thereby can derive viscosities il.

the 3rd operation

The 3rd operation is as described below: according to above-mentioned caloric value Q, above-mentioned constant alpha, following formula (III), derive and be supplied to supply ENERGY E above-mentioned the 2nd resin forming product side, time per unit, per unit area _s.

[formula 9]

E _s＝A×α×Q …(III)

(A establishing in formula (III) is constant)

Because Q, α in above formula (III) are same as described above, therefore the description thereof will be omitted.Coefficient A is for removing constant produced caloric value Q, contributed to make the caloric value outside this resin forming product melting by a resin forming product absorption.This constant can be derived by method described later.In addition, as described later, when determining suitable welding condition, do not need the concrete value of constant A.Therefore,, in determining the method for welding condition, can use the coefficient A of arbitrary constant.

In addition, α is the predetermined end face 101 of welding for considering the 1st resin forming product 10 melting area S when engaging ₁melting area S with the predetermined end face 111 of welding of the 2nd resin forming product 11 when engaging ₂the value of difference.Above-mentioned caloric value Q is S ₁=S ₂time per unit area, the caloric value that time per unit produces.Work as S ₁and S ₂when unequal, when deriving the energy that per unit area is supplied with, need to be multiplied by α and doubly proofread and correct.

the 4th operation

In the 4th operation, when establish between the 1st resin forming product 10 before and after engaging and the 2nd resin forming product 11, along the difference of distance that applies the direction of above-mentioned plus-pressure P, be L, when establishing weld time and being T, according to following formula (IV), derive the absorption ENERGY E of being received by a resin forming product side draught _a.

[formula 14]

$E_a=E_s\×T\×\frac{1}{L/2}\·\·\·\left(\mathrm{IV}\right)$

Supply with ENERGY E _sit is the energy of time per unit, per unit area.Thereby, by being multiplied by weld time, and the energy of needed per unit area while deriving welding.

The poor L of distance be the pressure of the 1st resin forming product collapse length that part is absorbed in the 2nd resin forming product side along length and the 1st resin forming product of Z direction and.Therefore owing to can think the equal in length of the two in vibration welded, can think that the length that the 1st resin forming product is absorbed in the 2nd resin forming product side is L/2.Energy by needed per unit area when the welding is divided by L/2, the energy of needed per unit volume in the time of can obtaining welding.This energy is made as to absorption energy.

Weld time T is the needed time of welding, refers to self-excited oscillation and starts to the time that completes welding product.

the 5th operation

In the 5th operation, derive heat seal strength and the endergonic dependency relation of weld portion.Even change welding condition, endergonic scope when heat seal strength becomes large is also basic identical.Thereby, as long as become large endergonic scope once derive heat seal strength, just can easily determine suitable welding condition.

Can derive dependency relation by for example actual measurement.For example by following mode, utilize actual measurement to derive dependency relation.

First, the welding condition production welding product to stipulate.With said method, obtain the absorption energy under the welding condition of this regulation.Then, measure the heat seal strength of the weld portion of these welding product.There is no particular limitation to measure the method for heat seal strength, for example, can utilize the method described in embodiment to measure.

Then, change the conditions such as amplitude that plus-pressure, frequency, rail mounted in the welding condition of stipulating vibrate, derive the heat seal strength under different welding conditions and absorb energy.And derive further as required the heat seal strength under the different welding conditions of many groups and absorb energy.

In Fig. 6, represent heat seal strength and endergonic dependency relation.In (a) of Fig. 6, be illustrated in the absorption energy of deriving under 3 different welding conditions and the relation of heat seal strength.If the longitudinal axis is heat seal strength, establish transverse axis for absorbing energy.Owing to supplying with ENERGY E _sin comprise unknown coefficient A, so the absorption energy of transverse axis is A * constant.Here, the absorption energy of establishing under the 1st welding condition is E _a1, heat seal strength is F ₁, the absorption energy of establishing under the 2nd welding condition is E _a2, heat seal strength is F ₂, the absorption energy of establishing under the 3rd welding condition is E _a3, heat seal strength is F ₃.

The figure of dependency relation when (b) of Fig. 6 means the maximum with heat seal strength.The 1st welding condition～3rd welding condition is identical with Fig. 6 (a).If the absorption energy under the 4th welding condition is E _a4, heat seal strength is F ₄.As shown in Fig. 6 (b), when dependency relation has maximum, as described later, can in countless welding conditions, select suitable welding condition.In addition, owing to can knowing the roughly upper limit of heat seal strength, needed workload and time in the time of therefore can significantly cutting down selected welding condition.

But if plus-pressure P is greater than certain value above (or more than a certain threshold value), there is the tendency reducing in heat seal strength.As mentioned above, even if change welding condition, endergonic scope when heat seal strength becomes large is also basic identical.Therefore,, by compare heat seal strength in this endergonic scope, can easily determine the threshold value of plus-pressure P.

In addition, also can not actual measurement weld time when derive absorbing energy, and use following formula (V).Once if deriving (V) does not need the workload of actual measurement weld time.

If the poor L of the above-mentioned distance setting is larger, weld time T is elongated, if above-mentioned caloric value Q is larger, weld time T shortens, if plus-pressure P is larger, weld time T shortens.Therefore, by following formula (V), represent weld time T.

[formula 15]

$T=\frac{B\×L}{{\left(Q\right)}^m\×{\left(P\right)}^n}\·\·\·\left(V\right)$

(B in formula (V) is coefficient, and m, n are constant.)

By matching actual measured value in formula (V), and obtain the value of B, m, n.In formula (V), before matching actual measured value, preferably by following method, select the actual measurement data that matching is used.

In order to derive the dependency relation of weld time and heat seal strength, the transverse axis of take is made chart as heat seal strength as weld time, the longitudinal axis of take.And obtain as shown in Figure 7 at weld time, be T _thtime heat seal strength become the such relation of maximum.If weld time is long, source of error etc. becomes large, and the reliability of formula (V) reduces, therefore not preferred.In addition,, if because weld time is too short, exist and can not consider that heat seal strength becomes the possibility of large condition, therefore not preferred.By using weld time, be T _thnear following actual measured value, when considering the condition that heat seal strength is higher, the reliability of the formula that source of error etc. can be caused reduces and is suppressed to Min..

If use the weld time of deriving as described above, formula (IV) can be deformed into following formula (VI).

[formula 16]

$E_a=2\×\frac{A\×B\×\mathrm{\α}}{{\left(Q\right)}^{m-1}\×{\left(P\right)}^n}\·\·\·\left(\mathrm{VI}\right)$

the 6th operation

In the 6th operation, based on above-mentioned dependency relation, determine welding condition.For example, according to Fig. 6 (a), (b), the scope that is certainly judged as larger heat seal strength or is judged as larger heat seal strength reads required endergonic scope.Based on determined endergonic scope, determine welding condition.As long as make welding product with so definite welding condition, just can access the very large welding product of heat seal strength of weld portion.

An example to the 6th operation describes.Scope (the E of the Δ E being judged as at Fig. 6 (b) _aL≤ E _a≤ E _aH) in heat seal strength larger.Endergonic scope when now, heat seal strength becomes large is following inequality (iii).

[formula 17]

$E_{\mathrm{aL}}\≤E_s\×T\×\frac{1}{L/2}\≤E_{\mathrm{aH}}\·\·\·\left(\mathrm{iii}\right)$

According to this inequality (iii), determine welding condition.But, supplying with ENERGY E _sin contain unknown constant A.But, due to E _aL, E _aHin remaining the state of coefficient A, therefore when determining welding condition, do not need to consider A too.

In addition, while stating in the use formula (V), can more easily determine suitable welding condition.Below represent concrete grammar.

Here, first determine and can be judged as the endergonic scope that heat seal strength is larger.Identical with the situation of above-mentioned explanation, the scope (E of the Δ E being judged as at Fig. 6 (b) _aL≤ E _a≤ E _aH) in heat seal strength larger.Endergonic scope when now, heat seal strength becomes large is following inequality (iv).

[formula 18]

$E_{\mathrm{aL}}\≤2\×\frac{A\×B\×\mathrm{\α}}{{\left(Q\right)}^{m-1}\×{\left(P\right)}^n}\≤E_{\mathrm{aH}}\·\·\·\left(\mathrm{iv}\right)$

Here, by E _aLthe formula (VI) of substitution formula (VI) gained ' and by E _aHthe formula (VI) of substitution formula (VI) gained " as follows.In above-mentioned inequality (iv), because α has the dependency relation (α=X with amplitude Δ X _s/ (Δ X+X _s)), so formula (VI) ', formula (VI) " can be that amplitude, the longitudinal axis are stressed graphical presentation (because without considering as described above constant A, just can derive Q) by transverse axis.As welding condition, when adjusting the amplitude of plus-pressure P or rail mounted vibration, can illustrate suitable welding condition with plane.So, by adjusting the amplitude of plus-pressure P, rail mounted vibration so that heat seal strength becomes large, and can easily determine suitable welding condition.

[formula 19]

$E_{\mathrm{aL}}=2\×\frac{A\×B\×\mathrm{\α}}{{\left(Q\right)}^{m-1}\×{\left(P\right)}^n}\·\·\·\left(\mathrm{VI}\right)\text{'}$

[formula 20]

$E_{\mathrm{aH}}=2\×\frac{A\×B\×\mathrm{\α}}{{\left(Q\right)}^{m-1}\×{\left(P\right)}^n}\·\·\·\left(\mathrm{VI}\right)\text{'}\text{'}$

the deriving method of constant A

Deriving method to constant A describes.Scope (E for the larger Δ E of heat seal strength _aL≤ E _a≤ E _aH), the temperature that can think resin when welding is increased to the scope that the degree of the abundant melting of resin and the temperature of resin are increased to the degree that resin can thermal decomposition.Can think that needed absorption energy is E for the temperature of resin being increased to the degree of abundant melting here, _aLabove, for resin forming product being applied to the degree that heat to resin can thermal decomposition, needed absorption energy is E _aHbelow.In the endergonic situation of regulation, vibrated the impact of produced heat, no matter what degree is the temperature of resin rise (increasing extent of temperature) to, can both be obtained by following formula (v).

[formula 21]

(specific heat in formula (v), density are for forming specific heat and the density of resin forming product.)

Substitution E _aL, form specific heat, the density of the resin (following, or referred to as " resin ") of resin forming product, from formula (v), derive that to absorb energy be E _aLtime increasing extent of temperature.If this increasing extent of temperature is Δ T _aL.Equally also can derive absorption energy is E _aHtime increasing extent of temperature, establishing this increasing extent of temperature is Δ T _aH.If welding the 1st resin forming product and the 2nd resin forming product at 23 ℃ of room temperatures, can think that when absorbing energy be E _aLtime, the temperature of molten resin during welding is (23 ℃+Δ T _aL).On the other hand, can think that when absorbing energy be E _aHtime, the temperature of molten resin during welding is (23 ℃+Δ T _aH).

(23 ℃+Δ T _aL) must be the such temperature of degree that makes the abundant melting of resin forming product.More than can thinking that the temperature of abundant melting is roughly the melting point of resin.In addition can think, (23 ℃+Δ T _aH) be roughly the temperature that resin can thermal decomposition.Thereby, if (23 ℃+Δ T _aL) be that the melting point of above-mentioned resin is above, (23 ℃+Δ T _aH) be below the thermal decomposition point of above-mentioned resin, the value of coefficient A is comparatively suitable.Consider if so, can be by following mode Coefficient of determination A.

First, work as E _aL* A ', while absorbing energy, derives (23 ℃+Δ T _aL) A ' while being melting point.Then, work as E _aL* A " be, while absorbing energy, to derive (23 ℃+Δ T _aH) A during for thermal decomposition point ".Due to A '～A " be the optimum range of A, therefore by Coefficient of determination A within the scope of this, obtain the value of suitable A.Can be by for example calculating A ', A " mean value as the method for the value of coefficient A, obtain the value of suitable A.In addition, about melting point, thermal decomposition point, even if use near near the temperature that melting point is, thermal decomposition point is, also can determine suitable coefficient A.

Below, represent embodiment and illustrate the present invention, but the invention is not restricted to these embodiment.

embodiment 1

In embodiment 1, determined and manufactured by (a), the 1st resin forming product shown in (b) and Fig. 8 of Fig. 8 (c), suitable welding process (the 1st resin forming product shown in Fig. 8 is identical with the shape of the formed products shown in Fig. 1 with the 2nd resin forming product) during the welding product that the 2nd resin forming product shown in (d) forms.(a) of Fig. 8, (c) are respectively the figure of section that schematically shows the side of resin forming product.(b) of Fig. 8 is the ground plan of the 1st resin forming product, is (d) the upper surface figure of the 2nd resin forming product.The 1st resin forming product, the 2nd resin forming product are resin (Port リ プ ラ スチツク ス Co., Ltd. system, trade name " FORTRON (registration mark) 1130T6 ", 280 ℃ of melting points, 420 ℃ of heat decomposition temperatures, density 1520kg/m by polyphenylene sulfide ³, specific heat 948J/kgK) form, and manufactured by injection molded method.

In vibration welded in embodiment 1, the vibration welded device (プ ランソン society system, trade name " ORBITAL WELDER (MODEL 100) ") that has used market to sell.In addition, the condition of vibration welded is: frequency is 207Hz, amplitude (table 1), between the 1st resin forming product before and after welding and the 2nd resin forming product, along poor (setting value) that apply the distance of stressed direction, be 0.8mm, vibration mode is rail mounted pattern, and pressurization start cylinder diameter is 125mm, plus-pressure (air pressure) (table 1), plus-pressure (actual effect) (table 1), weld time (table 1).Measured the heat seal strength of each welding product.As described in Figure 9, the measurement of heat seal strength is in this way to carry out: 11 the bottom of cutting away welding product, the mode that bottom with 10 is positioned at downside is placed on welding product for supporting the stationary fixture of 11 weld portion outer rim, and measure when pressing 10 bottom from top with pressure P, make weld from load.Table 1 has also represented the measurement result of heat seal strength.In addition, the thickness of melting layer is 0.1mm (confirming by having measured the length of weld marks on the destroyed welding product after measuring at heat seal strength).

[table 1]

the first operation

Owing to using 1st resin forming product, 2nd resin forming product identical shaped with above-mentioned embodiment, therefore from the rectangular reciprocating motion shown in Fig. 4, derive α in the same manner with embodiment.

According to Fig. 8, set X _sfor 2mm, Y _sfor 1mm.X is as shown in the table for amplitude Δ.Thereby, amplitude, S ₁, S ₂, α is as shown in the table.

[table 2]

the second operation

According to above formula (II), derive caloric value.According to above formula (i), derive vibration velocity, and derived shear rate according to above formula (ii).Table 3 has represented the vibration velocity, the shear rate that derive.In addition, about viscosity, the temperature of establishing molten resin is 300 ℃, obtains the relational expression of the relation that represents viscosity and shear rate with said method, and has derived viscosity according to this relational expression.Table 3 has also represented viscosity.

According to the vibration velocity, shear rate, the viscosity that derive like that above, derived caloric value.Table 3 has represented derivation result.

[table 3]

the 3rd operation～five operation

If constant A is 1/2, according to formula (III), derived the supply energy under each condition.Then, use the value of this supply energy, according to formula (IV), derived the endergonic value under each condition.Figure 10 has represented heat seal strength and endergonic relation.The solid line C of Figure 10 is that plus-pressure (air pressure) is the curve of 0.2MPa, 0.4MPa, and dotted line D is that plus-pressure (air pressure) is the curve of 0.6MPa.Endergonic scope when heat seal strength uprises is 2.6～3.0J/mm ³.Based on this scope, by deriving the scope of the supply energy of heat seal strength while uprising, then derive further the scope of the caloric value of heat seal strength while uprising, can easily determine preferred welding condition (amplitude that rail mounted vibrates, frequency etc.).

In addition, confirmed to serve as reasons near 0.5MPa and increased the threshold value that heat seal strength that plus-pressure causes reduces.

embodiment 2

In order to derive the relation of heat seal strength and weld time, in Figure 11, having made transverse axis is the chart that weld time, the longitudinal axis are heat seal strength.In the making of this chart, only used plus-pressure (air pressure) for the result of 0.2MPa, 0.4MPa.This is to cause the reduction of heat seal strength because can find out as described above at plus-pressure (air pressure) for stressed reduction under the condition of 0.6MPa.

Result from Figure 11 is known, and heat seal strength when weld time is about 10 seconds is maximum.If weld time is longer than 10 seconds, heat seal strength reduces.Here, using weld time is 20 seconds following data, the relational expression of deriving (V).Relational expression is following formula (vi).The chart that has represented together relational expression (vi) in Figure 12.

[formula 22]

$T=\frac{1.75\×L}{{\left(Q\right)}^2\×{\left(P\right)}^1}\·\·\·\left(\mathrm{vi}\right)$

By formula (vi) substitution formula (VI), become following formula (vii).

[formula 23]

$E_a=\frac{1.75\×\mathrm{\α}}{{\left(Q\right)}^1\×{\left(P\right)}^1}\·\·\·\left(\mathrm{vii}\right)$

determine constant A (derive and absorb energy)

Absorption energy is 2.6J/mm ³time increasing extent of temperature be 1856 ℃, absorption energy is 3.0J/mm ³time increasing extent of temperature be 2086 ℃.Absorption energy is 0.95J/mm ³time the temperature of the resin of increasing extent of temperature while being 280 ℃ (melting points of polyphenylene sulfide)-measure, constant A is now 0.14.In addition, absorbing energy is 3.0J/mm ³time the temperature of the resin of increasing extent of temperature while being 420 ℃ (thermal decomposition points of polyphenylene sulfide)-measure, constant A is now 0.19.Establishing constant A here, is 1/2 to have derived above-mentioned endergonic preferable range (2.6～3.0J/mm ³).Thereby, when using, take polyphenylene sulfide while being the resin resin that is main component, by constant A is made as to 0.28～0.38, can estimate the absorption energy that the light absorption resin forming product when welding absorbs.

Claims (7)

1. definite method of a welding condition, it is for determining the welding condition when the production welding product by this way, that is: the parallel direction of bearing surface forming along abutting against each other with by the predetermined end face of welding respectively with a pair of resin forming product of the predetermined end face of welding, apply the plus-pressure of the direction vertical with above-mentioned bearing surface on one side, make at least one resin forming product vibration on one side, thereby a pair of resin forming product of welding, wherein

When the melting area of the predetermined end face of welding of establishing a resin forming product during in welding is S ₁, the melting area of the predetermined end face of welding when welding of establishing another resin forming product be S ₂time, the constant definition that following formula (I) is represented is α,

$\mathrm{\α}=\frac{2\×S_1}{S_1+S_2}\·\·\·\left(I\right)$

Wherein, establish α≤1 in formula (I),

When if the vibration velocity during vibration of above-mentioned at least one resin forming product be V, to establish shear rate be V _sh, due to above-mentioned vibration melting the viscosity of resin while being η, the Q that following formula (II) is represented is defined as the caloric value that time per unit, per unit area produce on above-mentioned bearing surface,

Q＝V _sh×η×V···(II)

If for considering that the constant of energy above-mentioned caloric value, that absorbed by above-mentioned another resin forming product is A, the E that following formula (III) is represented _sbe defined as and be supplied to supply energy above-mentioned another resin forming product side, time per unit, per unit area,

E _s＝A×α×Q···(III)

Between a resin forming product before establishing welding and another resin forming product, along between the distance that applies above-mentioned stressed direction and the resin forming product after welding and another resin forming product, along the difference that applies the distance of above-mentioned stressed direction be L, when establishing weld time and being T, by the E of following formula (IV) expression _abe defined as the absorption energy of the per unit volume of being received by above-mentioned another resin forming product side draught,

$E_a=E_s\×T\×\frac{1}{L/2}\·\·\·\left(\mathrm{IV}\right)$

Heat seal strength based on weld portion and absorption ENERGY E _adependency relation determine welding condition.

2. definite method of welding condition according to claim 1, wherein,

This determines that method is following operation,, by following formula (V), represents above-mentioned weld time T that is,

$T=\frac{B\×L}{{\left(Q\right)}^m\×{\left(P\right)}^n}\·\·\·\left(V\right)$

Wherein, B, the m in formula (V), n are constant,

Endergonic scope while determining that based on above-mentioned dependency relation heat seal strength becomes large, E _aL≤ E _a≤ E _aH, wherein, E _aLfor the temperature of resin being increased to the needed endergonic minimum of a value of degree of abundant melting, E _aHfor resin forming product being applied to the needed endergonic maximum of degree that heat to resin can thermal decomposition,

Based on by E _aLthe formula (IV) of the above-mentioned formula of substitution (IV) gained ' and by E _aHthe formula (IV) of the above-mentioned formula of substitution (IV) gained " determine welding condition,

$E_{\mathrm{aL}}=2\×\frac{A\×B\×\mathrm{\α}}{{\left(Q\right)}^{m-1}\×{\left(P\right)}^n}\·\·\·{\left(\mathrm{IV}\right)}^{,}$

$E_{\mathrm{aH}}=2\×\frac{A\×B\×\mathrm{\α}}{{\left(Q\right)}^{m-1}\×{\left(P\right)}^n}\·\·\·{\left(\mathrm{IV}\right)}^{,,}.$

3. definite method of welding condition according to claim 1, wherein,

Dependency relation when above-mentioned dependency relation has the maximum of heat seal strength.

4. definite method of welding condition according to claim 2, wherein,

Dependency relation when above-mentioned dependency relation has the maximum of heat seal strength.

5. according to definite method of the welding condition described in any one in claim 1 to 4, wherein,

It is that resin is main component that the contained resinous principle of above-mentioned a pair of resin forming product all be take polyphenylene sulfide,

Above-mentioned A is 0.28～0.38, and above-mentioned m is 2, and said n is 1.

6. according to definite method of the welding condition described in any one in claim 1 to 4, wherein, this determines that method comprises following operation:

Based on above-mentioned absorption ENERGY E _aendergonic scope, Δ E when setting heat seal strength and become large with the relation of heat seal strength _a, Δ E _afor E _aLto E _aHscope;

A ' when calculating temperature that derived by increasing extent of temperature, the above-mentioned resin when welding and becoming melting point, this increasing extent of temperature is to use following formula (v) by E _aLconstant times E _aLdensity, the specific heat meter of the resin of * A ', formation resin forming product are calculated;

A when calculating temperature that derived by increasing extent of temperature, the above-mentioned resin when welding and becoming thermal decomposition point ", this increasing extent of temperature is to use following formula (v) by E _aHconstant times E _aH* A ", the density, the specific heat meter that form the resin of resin forming product calculate; And

At the A ' deriving to A " scope in select constant A arbitrarily,

Wherein, the specific heat in formula (v), density are for forming specific heat and the density of the resin of resin forming product.

7. definite method of welding condition according to claim 5, wherein, this determines that method comprises following operation:

Based on above-mentioned absorption ENERGY E _aendergonic scope, Δ E when setting heat seal strength and become large with the relation of heat seal strength _a, Δ E _afor E _aLto E _aHscope;

A ' when calculating temperature that derived by increasing extent of temperature, the above-mentioned resin when welding and becoming melting point, this increasing extent of temperature is to use following formula (v) by E _aLconstant times E _aLdensity, the specific heat meter of the resin of * A ', formation resin forming product are calculated;

A when calculating temperature that derived by increasing extent of temperature, the above-mentioned resin when welding and becoming thermal decomposition point ", this increasing extent of temperature is to use following formula (v) by E _aHconstant times E _aH* A ", the density, the specific heat meter that form the resin of resin forming product calculate; And

At the A ' deriving to A " scope in select constant A arbitrarily,

Wherein, the specific heat in formula (v), density are for forming specific heat and the density of the resin of resin forming product.