CN205179289U - Sound signal line - Google Patents

Abstract

The utility model relates to a sound signal line that sound signal line prevents especially that loudspeaker from during the frame vibration, producing the rope skipping effect. This sound signal line includes: a first group support level unit forms first space by N strip stranded conductor in the stranded conductor, second group support level unit forms the second space by N strip stranded conductor in the stranded conductor, first putting together is knitted, has 2N stranded conductor unit, a second is put together and is knitted, has 2N stranded conductor unit, first group support level unit and second group support level unit are by roughly along circumference route each other with be used for as this sound signal line's support to first space overlaps in central part second space mutually, first putting together is knitted the unitary system and with rotatory mode, along first and second group's support level units, is knitted sound signal line afterwards, and vertical directional line unit in its closed -loop's who transversely forms around support level unit of this first group first route sees through the second space of formation in the second group support level unit.

Description

Sound signal line

[technical field]

This creation relates to a kind of sound signal line, particularly prevents loudspeaker during sounding vibration, produces the sound signal line of rope skipping effect, have higher pliability and tensile strength, make the signal line in loudspeaker can transmit sound signal more enduringly.

[background technology]

With reference to Fig. 1, typical loudspeaker 1, comprising: horn frame 2, drum paper 3, one plays ripple 4, sound signal line 5, magnet 6, magnetic circuit (not shown), a speech coil framework (not shown) and a voice coil loudspeaker voice coil 7.A kind of sound signal, in the form of electric current, sends 5 through described sound signal line, is connected to horn frame 2 and voice coil loudspeaker voice coil 7, can produces magnetic field by this in this space from external signal input terminal 8, particularly the generation magnetic field, position of voice coil loudspeaker voice coil 7 and magnet 6 wherein.Produce gravitation and repulsion between magnetic field and magnetic circuit, make vibrate and produce the sound of expecting.Loudspeaker 1 are provided with the wire that the sound signal line (as so-called wire, stranded conductor or tinsel cord) of a pair or two couple are as shown in Figure 1 positioned at opposition side usually, and it is used in large-sized loudspeaker usually, such as secondary bass horn.One end of each sound signal line 5 is fixed to horn frame 2 and is coupled to described signal input end mouth 8, and is connected to the other end of described voice coil loudspeaker voice coil 7.Along with loudspeaker 1 produce sound, sound signal line 5 vertically can vibrate together with barrier film 3.

The sound signal line for sending sound signal at loudspeaker used at present is formed through each unit of braided wire.Each braiding linear system is by fiber in one and formed around the conductive metal sheet of described interior fiber.Through weaving the sound signal line formed completely, there is relatively low rigidity.When sound signal exceedes a certain frequency, it causes the amplitude of vibration increased can exceed required degree, sound signal line also horizontal vibration or produce the vertical vibration of ripple, as shown in Fig. 1 reference value 9; Traditionally, this is called as rope skipping effect.The rope skipping effect produced by the sound signal line of undue oscillation, may have influence on bulging paper 3 or play ripple 4, and then producing noise, seriously reducing the tonequality of loudspeaker.This effect also may cause contacting with each other between sound signal line, thus produces the sound signal of short circuit.What is worse, rope skipping effect may cause sound signal line get to bulging paper 3 or play ripple 4, thus the infringement causing some more serious.

In order to eliminate rope skipping effect, Taiwan Patent the 087220313rd discloses a kind of loudspeaker, wherein, through vacuum plating process, in the upper end face and the lower surface that play ripple, is coated by conductive metal layer.This process allows this conductive metal layer to replace traditional sound signal line and is connected to a voice coil loudspeaker voice coil, prevents rope skipping effect and noise thus.No. 5125473, United States Patent (USP) discloses another bullet ripple of a kind of loudspeaker, and wherein, the sound signal component for the sound signal launched is fixed to this bullet ripple, prevents sound signal component from can split because of rigidity and hot strength deficiency thus.Through playing wave surface applying conductive metal level or fixing sound signal component above, manufacture loudspeaker all will be made more complicated.In addition, misoperation is easy to the transmission quality that can reduce sound signal.

Because shortcoming discussed above, this creation provides a kind of braiding structure of improvement, has higher rigidity and pliability to produce, and without the need to performing the sound signal line of complex process.This sound signal line can prevent tinsel cord from producing in high-frequency vibration institute effect of skipping rope, and does not affect sound quality or causes infringement.It also makes wire more durable, thus the useful life of the loudspeaker extended.

Author content

The main purpose of this creation, the Speech input mouth to loudspeaker and a loudspeaker oscillating plate, one wire is provided, wherein, described wire is formed by specific braiding structure, to allow higher rigidity, make sound signal line under high-frequency and lasting vibration, still can eliminate the generation of rope skipping effect.This sound signal line is through the method providing two groups of wires, and wherein, the first group of line unit forms a support, and the second group of line unit form one group of peripheral wire braiding.

Another object of this creation, be to provide a kind of sound signal line, it has larger tensile strength and more lasting useful life, wherein, the line unit of each formation signal line, including the interior fiber with made by super heat resistance fiber, and this super heat resistance fiber, is formed through the poly-Para-aromatic Aramide Fibre of mixed weaving and poly-meta-aramid fibers.

Another object of this creation is to provide a kind of sound signal line, wherein, described electric wire is immersed in the solution of acetal resin or polyurethane, and forms the coating on the surface of line, thus add rigidity wiry, the rope skipping effect that the sharp pounding of loudspeaker causes can be avoided.

But, another object of this creation, be to provide one to have: the sound signal line of the combination of the aforementioned interior fiber that (1) is comprised as each line unit by conductive metal sheet, (2) weave two groups of line unit and inweaved signal line, and last (3) impregnated wire is in specific wax oil, to form final products, it has higher rigidity, and avoid the generation of rope skipping effect, and improve tensile strength, pliability and durability.

Detailed technology contents and embodiment, those skilled in the art by the diagram of this creation and can describe, and fill the technical characteristic that part understands this creation.

Accompanying drawing explanation

Fig. 1 is known loudspeaker, sound signal line wherein, has the schematic diagram of rope skipping effect;

Fig. 2 A be with braiding before under static conditions, the sectional view of the sound signal line of traditional 12 twisted wire unit;

Fig. 2 B is the cutaway view along next braiding process particular path of the sound signal line with 12 twisted wire unit

Fig. 3 weaves with 12 twisted wires, the perspective view of the line unit of its sound signal line;

Fig. 4 A is the sectional view of the layout of a sound signal line, according to this creation, and 12 twisted wire unit under static conditions before braiding;

Fig. 4 B is the layout sectional view of a sound signal line, according to this creation, wherein only has 8 twisted wire unit along particular path, braiding other 4 twisted wire unit around;

Fig. 5 is a sound signal line, according to the perspective view of the layout of this creation;

Another sectional view arranged of the sound signal line that Fig. 6 A is, according to this creation, before braiding, 18 twisted wire unit under static conditions;

Another sectional view arranged of the sound signal line that Fig. 6 B is, according to this creation, wherein only has 12 twisted wire unit along particular path, braiding other 6 twisted wire unit around;

Fig. 7 A with 4A schemes similar, and with each Support Level unit and litzendraht wire unit, this litzendraht wire unit comprises interior fiber and surrounds the conductive metal plate of this interior fiber;

Fig. 7 B is similar with Fig. 4 B, and at each Support Level unit and litzendraht wire unit, litzendraht wire unit comprises interior fiber and surrounds the conductive metal plate of this interior fiber.

Description of reference numerals

1: loudspeaker

2: horn frame

3: drum paper

4: play ripple

5: sound signal line

6: magnet

7: voice coil loudspeaker voice coil

8: signal input end

13,14: lead unit

20: sound signal line

The Support Level unit of 21: the first groups

The Support Level unit of 22: the second groups

31: the first groups of weaving units

32: the second groups of weaving units

35: the first closed-loop paths

36: the second closed-loop paths

41: the first groups of Support Level unit

42: the second groups of Support Level unit

51: the first groups of litzendraht wire unit

52: the second groups of litzendraht wire unit

55: the first closed loops

56: the second closed loops

211,221: interior fiber

311,321: conductive metal plate

Preferred embodiment

General sound signal line 5, through known weaving method manufacture, may have 8 strands, 12 twisted wires, 16 twisted wires usually, and 20 strands or 24 twisted wire litzendraht wire unit, this depends on the demand of required product and the pattern of braiding machine.Such as, reference diagram.Fig. 2 A and 2B, 12 strands of sound signal lines have manufactured by the rotary braiding machine of 12 roller bearings by one, and wherein this roller bearing is arranged to two groups, each roller is wound with the particular path in lead unit 13 or 14, as figure Fig. 2 B, to perform rotation weaving, and form the end of sound signal line 5.Similarly, have the sound signal line of the line unit of 8,16,20 or 24 twisted wires through use, loom is made and is had 8,16,20 or 24 roller bearings respectively.

Braiding machine known as above, is also applicable to this creation.At needs, through the sound signal line of the mode of example, the line unit of 12 twisted wires, and make it to have with loom 8 circles and arrange roller bearing, 8 twisted wire braided wires can be wound into 8 roller bearings, then rotate along weaving process with roller to perform the rotation being similar to prior art.Surrounded by 8 roller bearings at center, also have other one group of electric wire, such as, 4 supports as 8 strands of knit wire unit.

Be woven in 4 bursts of Support Level unit embodiments according to aforesaid 8 twisted wire unit, with reference to figure 4A and Fig. 4 B, this sound signal line 20, include: the first space in the twisted wire that two twisted wires of the Support Level unit 21 of first group are formed, and the second space in the twisted wire that formed of two twisted wires of the Support Level unit 22 of second group, wherein, described first space and second space are virtual, and therefore its border does not illustrate in the drawings.The core of these two imaginary spaces Support Level unit of four strands of overlapping place each other.On the other hand, this sound signal line 20 more includes: four strands of first group of weaving unit 31, and four of second group of weaving unit 32 strands is good.The Support Level unit 22 of this Support Level unit of first group 21 and second group.

According to said structure, litzendraht wire unit 31,32 is woven into Support Level unit 21,22, carries out complicated three-dimensional motion.Specifically, first group of Support Level unit 21 is to form the first space by N bar twisted wire in twisted wire; One second group of Support Level unit 22, forms second space with N bar twisted wire in twisted wire; One first group of weaving unit 31, has 2N twisted wire unit; One second group of weaving unit 32, has 2N twisted wire unit; Wherein: N is that integer is equal to or greater than 2; First group of Support Level unit 21 and second group of Support Level unit 22, by roughly along circular path each other with in order to the support as this sound signal line, and the first space overlaps mutually at core second space; First group of weaving unit 31 is in rotary manner, along first and second groups of Support Level unit, knit sound signal line subsequently, it is laterally around the longitudinal direction line unit in the first path of the first closed-loop path 35 (dotted line with reference to shown in Fig. 4 B) that this Support Level unit of first group is formed, through the second space formed in second group of Support Level unit; Be in rotary manner with second group of weaving unit 32, along first and second groups of Support Level unit, knit sound signal line subsequently, it is laterally around the longitudinal direction line unit in the second path of the second closed-loop path 36 that this Support Level unit of second group is formed, through the first space formed in first group of Support Level unit.

Another embodiment of sound signal line, performs the rotation braiding process being similar to previous embodiment.Bus unit has 18 twisted wires, and loom has 12 roller bearings, and the braided wire of 12 twisted wires can be wrapped in 12 roller bearings, then centrally surrounds rotation with roller bearing, also has, and such as, 6 twisted wires are as its 12 twisted wire litzendraht wire unit of support.

According to 6 twisted wires as supporting in the embodiment of its 12 twisted wire litzendraht wire unit, with reference to figure 6A.With Fig. 6 B, sound signal line 40, comprise: the first space in three strands of twisted wires formed of the Support Level unit 41 of first group, and three strands of the Support Level unit 42 of the second group second spaces formed in twisted wire, wherein, described first space and second space are virtual, and therefore its border does not illustrate in the drawings.These two imaginary spaces, the core of the Support Level unit of 6 lines that overlap each other.Sound signal line 40 more includes: 6 lines of first group of litzendraht wire unit 51, and 6 of second group of braided wires unit 52 lines, and the Support Level unit 42 of this Support Level unit of first group 41 and second group.

According to said structure, in a second embodiment, litzendraht wire unit 51,52 is woven into Support Level unit 41,42 through carrying out complicated three-dimensional motion.Specifically, first group of litzendraht wire unit 51 performs, to rotate, first and second group 41 of the Support Level unit knitted subsequently, 42 along the width direction 40 of signal line, it is laterally forms Support Level unit 41 around described first group, through the second space of formation in second group of Support Level unit 42 by the first path first closed loop 55 (the real diagram 6B with reference to shown) substantially.Similarly, second group of braided wires unit 52 transverse rotation, first and second groups of width directions along signal line of the upper Support Level unit of braiding subsequently, the surrounding of one second the second closed loop 56 (the dashed line view 6B with reference to shown) closed forms the Support Level unit 42 of second group through the first space formed in first group of Support Level unit 41 substantially.

At use Tradition Looms with 8,12,16,20 or 24 (this rule being set to a numeral is 4N, wherein N is as a whole is equal to or greater than 2) on roller bearing, a collection of 8,12,16, the litzendraht wire unit (4N) of 20 or 24 can be wound on roller respectively, with 4,6,8 of a number, 10 or 12 (arrange this rule for digital 2N, wherein, N is that an integer is equal to or greater than Support Level unit 2) be provided as the basis of the roller bearing that is weaving, thus the sound signal line of (4N+2N) twisted wire produced.

By first embodiment of Fig. 4 A and Fig. 4 B and N=3, with the second embodiment by Fig. 6 A and Fig. 6 B, the Support Level unit of 2N twisted wire, by the Support Level unit of the Support Level unit and second group of N bar twisted wire that are divided into the N bar twisted wire of first group equably; And the litzendraht wire unit of 4N twisted wire, be then divided into first group of braiding 2N twisted wire unit and second group of braiding 2N twisted wire unit equably.But, the sound signal line of the device of this creation, is not limited to the aforesaid number of braided wire.In other words, the number provided and the rule for supporting knitting arrangement be as mentioned above, and the number of Support Level unit and litzendraht wire unit can change, and to meet actual requirement, and reaches the expection object avoided about effect of skipping rope.

According to observations, if sound signal line is immersed in the solution of acetal resin or polyurethane composition, formed the coating on the surface of sound signal line, it even may improve line unit under rigidity without coating.This is because the solution of acetal resin or polyurethane has excellent adhesive force and the transparency, can be used as adhesive or coating.Dissolve acetal resin or polyurethane in a suitable solvent, sound signal can be coated in online, effectively to improve the rigidity of sound signal line, thus make sound signal line be not easy to be subject to by the rope skipping effect of the vibration of high-frequency and amplitude.Above for diluting the solvent of acetal resin or polyurethane, have no particular limits.Any solvent dissolving acetal resin or polyurethane all can use; But, alcoholic solvent usually preferably select be: such as, but not limited to, methyl alcohol, ethanol, propyl alcohol or isopropyl alcohol.The solution of acetal resin or polyurethane, can pass through any suitable method, is coated to sound signal line, as dip-coating, and spraying, and direct applying.The solution of acetal resin can add further with multiple additives, comprise phosphate such as tributyl phosphate or TCP, phthalic acid ester (that is: DOP, DPB and BBP), phosphate, to phthalic acid ester, polyethylene glycol, triethylene glycol two butyric acid or castor oil, revise resin restriction inherently, particularly in increase plasticity.

In addition, sound signal line can further improve its hot strength and flexibility, makes wire more durable, each supporting-line unit 21,22 and litzendraht wire unit 31,32, can be designed as and comprise interior fiber 211,221 and conductive metal plate 311,321 surround interior fiber 211,221, as shown in figures 7 a and 7b, wherein, the example of the line unit of 12 twisted wires is only shown.Interior fiber 211,221 can by cotton fiber, rayon fiber, in the combination of polyester fiber and poly-aramid fibre, selects textile material.At above-mentioned poly-aramid fibre, poly-meta-aramid fiber, all has high-melting-point, high rigidity and stable characteristic.

On the other hand, poly-para-aramid fiber has very large hot strength, durability, chemicals-resistant and impact absorbing ability.They can be used as ballistic fiber, manufacture bullet-proof vest, bulletproof halmet and antiknock device.No matter permitted eurypalynous poly-aramid fibre, be used to the interior fiber making traditional sound signal line, be adopt single poly-Para-aromatic Aramide Fibre or poly-meta-aramid fibers.For asking better pliability and tensile strength, interior fiber 211,221 can be a strong heat resistance fiber, is made up of, thus prevented the sound signal line of loudspeaker from being shaken frequently and producing crack mixed the knitting of poly-meta-aramid fibers with poly-Para-aromatic Aramide Fibre.Conductive metal sheet 311,321 can by being selected from copper, cadmium, tin, in the combination of silver and their alloy, selects metal material to make.Be coated in conductive metal thin plate 311 with silver or tin, on 321, conductivity can be improved further.

Line unit described in embodiment 1 ~ 8 has been the sound signal line improved, and comprises interior fiber and the coated interior fiber of conductive metal plate.

Preparation example 1

Poly-inclined isophthaloyl amine is adopted to be used as the interior fiber of textile material.The specification that interior fiber adopts is 40-in-2 rope (wherein " 40-in-2 " refers to, the diameter of each 2 strands is 40Ne) and comprises by the copper foil applied with silver, forms a lead unit.Then, reeled by the line unit of 7 strands, then carry out anti-oxidant treatment at 82 DEG C, to form the sample 1 of sound signal line.

Preparation embodiment 2

The formation of the sample 2 of sound signal line, as process prepared by above-described embodiment 1, difference is, internal fiber is coated with the Copper Foil of silver, to form line unit by two panels

Preparation embodiment 3

The formation of the sample 3 of sound signal line, as process prepared by above-described embodiment 2, difference is, the specification that interior fiber adopts is 30-in-3 rope (wherein " 30-in-3 " refers to, the diameter of each 3 strands is 30Ne) etc.

Preparation embodiment 4

The formation of the sample 4 of sound signal line, as process prepared by above-described embodiment 3, difference is, only replaces use 7 twisted wire with the line unit of 4 twisted wires.

Preparation embodiment 5

Mixing gathered inclined metaphenylene diamides and gather terephthalate amine, as the material of internal fiber, it is coated with silver-colored Copper Foil with comprising by one single by the specification of band 40-in-2, forms a lead unit.Then, the line unit of winding 7 strands, carry out anti-oxidant treatment at 82 DEG C, to form the sample 5 of sound signal line.

Preparation embodiment 6

The formation of the sample 6 of sound signal line, and preparation embodiment 5 in said process is similar, difference is, internal fiber is coated by the Copper Foil of silver, to form line unit by two panels.

Preparation embodiment 7

The formation of the sample 7 of sound signal line, the same with the preparation embodiment 6 in said process, difference is, internal fiber is the specification adopting 30-in-3.

Preparation embodiment 8

The formation of the sample 8 of sound signal line, the same with the preparation embodiment 7 in said process, difference only need not 7 strands, and be only wound around with 4 strands of wires.

The sound signal line 8 that sample 1 is produced by Production Example 1 ~ 8, in difference table 1 below, demonstrates tested for tensile strength, pliability, conductivity, with test result.

Table 1

As shown in table 1, sound signal linear system is made up of resistance to high thermal fiber, it is be made up of the poly-meta-aramid fibers of mixed weaving and poly-para-aramid fiber (with reference to sample 5-8), compared with the traditional sound signal line being gathered meta-aramid fibers (with reference to sample 1-4) by single type and formed, have and larger pull intensity and pliability, and low conductor resistance.

Preparation embodiment 9

Use the poly-inclined metaphenylene diamides of mixing and gather terephthalate amine, being used as internal fiber, it is by the gauge material of band 40-in-2, and is surrounded by cadmium/copper alloy, the litzendraht wire unit formed.Then, according to known weaving method, the litzendraht wire unit of 12 twisted wires, with through using loom to be had the mode of 12 roller arrangement rotations, makes 12 twisted wire braided wires respectively along with the path of braiding 12 twisted wire circular rotating; Subsequently, woven silk unit is received in 82 DEG C of anti-oxidant treatments, to form the litzendraht wire unit of the sample 9 of the sound signal line of 12 twisted wires.

Production Example 10

According to this creation Fig. 4 A and 4B, carry out and above-mentioned similar process, to form litzendraht wire unit.Through using the braiding machine with 8 roller bearings, 8 litzendraht wire unit are placed by along 8 roller bearings, and 8 twisted wire litzendraht wires, along particular path, rotated and be woven into 4 line unit supported, and be have rotated a circle path with 8 rollers.Then, make litzendraht wire unit accept anti-oxidant treatment at 82 DEG C, to form the sample 10 of sound signal line.

Sample 9 and 10 stands different rotary speeies, tested by vertical vibration.Vibration condition is recorded in table 2 below.Through checking data, can be clear that, using the layout wherein weaving 4 twisted wires (i.e. sample 10) the fixed support line unit of 8 twisted wire unit, effectively eliminate the generation of rope skipping effect.

Table 2

Embodiment 11-12 establishes the sound signal line that improves rigidity, sound signal line surface on a coating certain layer demonstrate, as mentioned above, cause eliminating relevant rope skipping effect.

Preparation embodiment 11

Embodiment 11 is identical with the preparation condition of above-described embodiment 9.

Preparation embodiment 12

Embodiment 12 (using methyl alcohol as solvent), identical with the condition of above-described embodiment 9, form the sample 12 of sound signal line.Different person, the solution being sound signal line to be coated with acetal resin gets off preparation.

Sample 11-12 is through identical method, for embodiment 9-10, tests their vibrations. and carry out with different rotary speeies, vibration condition is recorded in table 3 below.Can find, sample 11 easily produces rope skipping effect, but sample 12 is not easy to produce.This represents, along with the coating of the solution of acetal resin, effectively can improve the rigidity of sound signal line, to prevent the generation of rope skipping effect.

Table 3

Preparation embodiment 13

Embodiment 13 is prepared with the condition identical with above-described embodiment 9.

Preparation embodiment 14

Embodiment 14 is prepared with the condition identical with above-described embodiment 9.Difference is the solution that sound signal line more scribbles polyurethane, to form the sample 14 of sound signal line.

Sample 13-14 uses embodiment 9-10, and through identical method, test their vibrations, carry out with different rotary speeies, vibration condition is recorded in table 4 below.Can to find, the rope skipping effect that sample 13 easily produces, but sample 14 being less likely to occur. this represents, the solution of coating polyurethane, can improve the rigidity of sound signal line effectively, with the generation of the effect that prevents from skipping rope.

Table 4

Although the present invention discloses as above with preferred embodiment; so itself and be not used to limit the present invention, any those skilled in the art, without departing from the spirit and scope of the present invention; when doing a little change and retouching, therefore protection scope of the present invention is as the criterion when defining depending on appended claim.

Claims (10)

1. a sound signal line, is characterized in that, comprising:

One first group of Support Level unit, forms the first space by N bar twisted wire in twisted wire;

One second group of Support Level unit, forms second space by N bar twisted wire in twisted wire; ;

One first group of braiding, has 2N twisted wire unit;

One second group of braiding, has 2N twisted wire unit; Wherein: N is that integer is equal to or greater than 2;

First group of Support Level unit and second group of Support Level unit, by roughly along circular path each other with in order to the support as this sound signal line, and the first space overlaps mutually at core second space;

First group of weaving unit system in rotary manner, along first and second groups of Support Level unit, knit sound signal line subsequently, it is laterally around the longitudinal direction line unit in the first path of the first closed-loop path that this Support Level unit of first group is formed, through the second space formed in second group of Support Level unit; With

Second group of weaving unit system in rotary manner, along first and second groups of Support Level unit, knit sound signal line subsequently, it is laterally around the longitudinal direction line unit in the second path of the second closed-loop path that this Support Level unit of second group is formed, through the first space formed in first group of Support Level unit.

2. sound signal line according to claim 1, it is characterized in that, N is 2.

3. sound signal line according to claim 1, it is characterized in that, N is 3.

4. sound signal line according to claim 1, is characterized in that, each described Support Level unit and litzendraht wire unit, is formed by fiber in around a conductive metal sheet of fiber in described.

5. sound signal line according to claim 4, it is characterized in that, described conductive metal thin plate is coated with silver.

6. sound signal line according to claim 4, it is characterized in that, described conductive metal thin plate is coated with tin.

7. sound signal line according to claim 6, is characterized in that, more include: an acetal resin, be coated in the surface of described sound signal line.

8. sound signal line according to claim 6, is characterized in that, more include: a polyurethane, be coated in the surface of this sound signal line.

9. sound signal line according to claim 1, is characterized in that, more include: an acetal resin, be coated in the surface of this sound signal line.

10. sound signal line according to claim 1, is characterized in that, more include: a polyurethane, be coated in the surface of this sound signal line.