CA1243927A

CA1243927A - Door pad, and method for manufacturing the same by application of ultrasonic wave

Info

Publication number: CA1243927A
Application number: CA000457221A
Authority: CA
Inventors: Muneharu Urai
Original assignee: Tachikawa Spring Co Ltd
Current assignee: Tachi S Co Ltd
Priority date: 1983-07-04
Filing date: 1984-06-22
Publication date: 1988-11-01
Also published as: IT8421747A0; GB2142574A; AU547977B2; GB8415839D0; GB2142574B; AU2985684A; IT1174236B; FR2548584B1; FR2548584A1; DE3424637A1

Abstract

ABSTRACT OF THE DISCLOSURE

A method for manufacturing a door pad by the application of ultrasonic wave is provided, which com-prises the steps of putting a surface layer material, a filler padding made of normal polyurethane which is not subjected to any previous treatment and a backing board, in a laminated state, between ultrasonic machining horns and ultrasonic machining horn rests, and applying ultra-sonic vibration to desired portions of said laminate by the ultrasonic machining horns. Also, a door pad manufac-tured by ultrasonic welding is provided, which comprises a laminate consisting of a surface layer material, a filler padding or polyurethane molding made of normal polyurethane which is not subjected to any treatment and a backing board, wherein desired portions of said laminate are fusion-bonded by heat produced therein by ultrasonic vibration. The door pad according to this invention is excellent in physical properties and cheap in price.

Description

i3~;~7 This invention relates to a door pad, and particularly to a door pad manufactured by welding normal polyurethane, which is not subjected to any treatment, under application oE ultrasonic wave. The present invention relates also to a method for manufacturing a door pad by the ultrasonic welding of normal polyurethane not subjected to any previous treatment for welding, which coulcl not be hitherto used in high frequency welding.
The prior art and preferred embodiments will now be described in conjunction with the accompanying drawings in which:
FIG. 1 is a schematic sectional view of a prior door pad.
FIGS. 2 to 5c are respectively schematic views showing embodiments of door pad according to this invention.
FIG. 2 is a schematic sectional view of a door pad, wherein a method for manufacturing the same is illustrated.
FI~. 3 is a schematic sectional view of a door pad in which the terminating ends of a surface layer are ixed on 20 the back side of a backing boardl enclosing the backing board~ `~
FIG. 4 is a schematic sectional view of a door pad having a filler padding partially difEerent in thickness.
FIG. 5a is a schematic sectional view of a door pad in which button-shaped portions are formed on and a welt-shaped member of separate body is welded to the surface of a surface layer.
FIG. 5b is a perspective view oE a welt-shaped member.

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,,,s,~, ~Z~3~327 FIG. 5c is a perspective view of a welt-shaped member in another contour.
A door pad used as the inner covering of a vehicle door or the like (which will be hereinafter called a door pad merely), has been hitherto manufactured by utilization of a high frequency heating or any other suitable heating means.
In FIG. 1, there is shown a prior example of such a door pad.
The prior door pad shown in FIG. 1 has mainly been manufactured by putting a surface layer-l and a backing board 3 one over the other, with a filler padding 2 interposed between them, compressing the surface layer 1, iller padding

2 and backing board 3 between high frequency electrode members (not shown) in contact with weld portions 2a and the other high frequency electrode members (also not shown) on the side of the opposite backing board 3, and kh/mab supplying a high frequency current between both these electrode members to fuse the filler padcling 2 so that the surface layer l and filler padding 2 are welded to the back-ing board 3 at the weld portions 2a.
In this case of the prior door pad, the bonding of the surface layer l, filler padding 2 and backing board

3 has been achieved by the fusion of the filler padding 2 (except for normal polyurethane which will be described below), because the filler padding 2 is fused by heat pro-duced therein upon the supply of a high frequency current, but the backing board 3 such as a hard board is not exo-thermical]y fused due to its selected material.
In the prior arts utilizing high frequency heat-ing, normal polyurethane not subjected to any previous treatment, by way of example an impregnation with a welding fiIler substance for improving its weldability with a high frequency current, (which will be hereinafter shortened normal polyurethane merely) was not used inspite of its excellent physical properties (elasticity, durability, etc.) and its lower price, since it can not be fused because of its hlgh melting point. Alternately, there have been hitherto used normal polyurethane treated so as to be capable of fusing at low temperatures, low melting point polyurethane and cushion materials with low melt1ng polnts other than polyurethane. However, these materials have various defects, :: ::

~3~ '7 that is inferior physical properties and higher prices as compared with normal polyurethane.
In order to use normal polyure1:hane, with utili-~ation of its excellent characteristics rnentioned above, sometimes, a substance that can be fused by a high fre-quency current has been previously applied to the surface of the backing board 3 to be contacted with the filler padding 2. But, this prior art has been less effective, resulting in the manufacturing steps increased in number and the cost raised.
In view of the above r the present invention is intended to provide a door pad manufactured by using normal polyurethane not subjected to any previous treatment under application of ultrasonic wave. Furthermore, the present inyention is intended to provide a method for manufacturing a door pad by the ultrasonic welding of normal polyurethane not subjected to any previous treatment for welding, which could not be hitherto used in high frequency welding.
According to one aspect of this invention, there is provided a door pad manufactured by ultrasonic welding, which comprises a laminate consisting of a surface layer material, a filler padding or polyurethane molding made of normal polyurethane which is not subjected to any treatment and a backing board, wherein desired~portions of said laminate are fusion-bonded by heat produced therein by ultrasonic vibration. 'rhe filler padding or moulding iB
partially fu~ed in the longitudinal (depth) direction between a weld portion and the backing board to weld the surface layer to the filler padding.
According to another a~pect of this invention, there iB
provided a method for manufacturing a door p~d by the application of ultrasonic wave~ which comprise~ the steps of putting a ~urface layer material, a polyurethane moulding or other filler padding made of normal, untreated~ polyurethane and a backing board, in a laminated state, between ultra30nic machining horns and ultrasonic machining horn rests, and applying ultrasonic vibration to deaired portion~ of the laminate by the ultrasonic machining horns, while a force is being imparted thereon, whereby the de~ired portion~ of the laminate are fusion-bonded by heat produced therein, in which the filler padding or moulding i8 fused partially in the longitudinal (depth) direction between a weld portion and the backing board, thereby to weld the surface layer to the filler padding.
~TAI~ED DE5CRIPTIO~ OF PR$F~RRED EMBODI~E~TS
This invention will be deecribed in det~il with reference to embodiments of door pad and method for manufac-turing the sam2 shown in FIG. 2 to 5c of the accompanying drawings, and prior arts other than the ones already mentioned above will be further described there for comparison.
Referring now to FIG. 2, there i~ ~hown therein a door pad according to thi3 invention. 'rhe door pad shown in FIG. 2 is manufactured by utili~ation of the ultrasonic vibrAtion-exothermic fusion proce~s which is quite different kh/ ~i ,~ , 3~27 from the prior arts, because normal polyurethane can not be exothermically fused by means of a dielectric loss caused by a high frequency current or another heating means, as mentioned in the above.
The door pad manufacturing method according to this invention comprises the steps of arranging ultrasonic machining horns 4 at weld portions 2a and ultrasonic machin-ing horn rests 5 on the back side of a backing board 3 ~such as a hard board), and causing the ultrasonic machining horns

4 to vibrate, while a surface layer l, a filler padding 2 and the backing board 3 are being pressed and compressed, and transmitting the ultrasonic vibration to the surface layer l, filler padding 2 and backing board 3 so tha-t the filler padding 2 made of normal polyurethane is mainly fused through the vibration of each of these layers and the surface layer l, filler padding 2 and backing board ars bonded. In such a case that the surface of the ~acking board 3 to be contacted with the filler padding 2, to which vibration is applied, and/or the surface layer l are fusible due to their selected materials and the given conditions of vibration, the surface layer l, fill.er padding 2 and backing board 3 will be bonded more strongly by heat produced with the ultrasonic vibration.
FIG. 3 shows another embodiment of door pad according to thls invention. In the door pad shown in FIG. 5, :

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the surface layer l is fixed on the back side of the back-ing board 3, with both its terminating ends la covering the circumference of the backing board 3.
In accordance this invention, all the circum-S ferences of the terminating ends la of the surface layer l are welded on the backing board 3 by means of the ultrasonic machining horns 4A and the ultrasonic machining horn rests SA wider in area, attached on the top side of the surface layer l, although in the prior arts, the terminating erlds la have been hitherto fixed thereon by the driving of metal fasteners by a tacker or the adhesion with an adhesive.
In this case of door pad shown ln FIG. 3, one of the surface of the backing board 3 in contact with the terminating ends la and the surfaces of the terminating ends la in contact with the backing board 3, or both of these surfaces are welded and bonded.
Since the width and area of the ultrasonic ~; machining horn rests 5A are larger than those of the :: :
ultrasonic machining horns 4A as shown in FIG. 3, the dents forced by the ultrasonic machining horn rests 4A or ultra-sonic machining horns 5~ are not remaining on the top side of the surface layer l. In addition, although not illus-trated, the ult~asonic machining horns 4A and the ultra-sonic machirling horn rests 5A may be used in the state of several divided parts, not in one block.

li, 3g;~7 With reference to FIG~ 4 showing a further embodi-ment of this invention, reference numeral 2A indicates a polyurethane molding or partially laminated filler padding.
This filler padding 2A is partially different in thickness.
When a high frequency current was caused to pass in order to partially weld a surface layer l at the weld portion 2b in the thick portion of a filler padding 2A in the prior high frequency heating process, it passed through all the region under the weld portion 2b, resulting in the fusion of all the region. In the prior process, namely, the fusion of only the surface layer l was impossible and the region under the weld portion 2b was of-ten cut.
In the door pad manufacturing method according to this invention, the weld portion 2b is partially fused in the longitudinal direction by means of the ultrasonic machining horn 4.
FIGS. 5 a , Sb and 5c show further embodiments according to this invention, in which button-shaped portions 2C are formed on and a welt-shaped member 6 of separate body is welded to the top surface of the surface layer l.
The button-shaped portion 2C shown in FIG. S ~
is formed by partially fusing the filler padding 2~ by use ~ : :
of~ a button-like shape-imparting ultrasonic machining horn (not shown) so that a portion of the surface layer l is ~ ~ 25 made to be in the shape of a button.

: ~ :

~Z~3~7 FIG. 5 b is a perspective view of a welt-shaped member 6. Although not illustrated, the welt-shaped member 6 may have a welt core covered therewith. FIG. 5 c shows another welt-shaped member 6A which is different in contour from the welt-shaped member 6 shown in FIG. 5 b , and this welt-shaped member 6A is in the form of a tap in that both the side ends of the welt-shaped member 6 are not folded inwardO The welt shaped member 6 or 6A is welded to the surface layer l by use of an ultrasonic machining horn (not shown).
The surface layer l and the welt-shaped member 6 shown in FIG. 5 b: or the surface layer l and the welt-shaped member 6A shown in FIG. S c may be made of different materials or in distinct contours, and further may have various colors and patterns in combination. In addition, a surface layer l which is divided under the welt-shaped member 6 or 6A may be used, and these divided portions will be welded and fixed by the welt-shaped member 6 or 6A.
~ ~ The embodiments, in all of which a hard board is used as the backing board 3, has been described in the above. Further, although not illustrated, a plastic mold-ing~or ~he like made by the injection or any other suitable : : molding of a plastic can be also used as the backing board 3.
Also in the case that such a plastic molding is used as the backing board 3 instead of sa1d hard board, it is capable .

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to weld the surface layer 1 and the same plastic molding as the backing boaxd 3, for example by partially fusing the filler padding 2 or 2A in the longitudinal direction or fusing the whole -thereof when re~uired, through the ultrasonic welding process rather than the prior high fre-quency heating process, as already mentioned in the above.
By the door pad manufacturing method according to this invention, it can be realized to use normal poly-- urethane excellent in physical properties and cheap in price, which could not be hitherto used, as the filler padding or polyurethane molding.
According to this invention, the surface layer of a door pad can be formed into desired shapes such as a button-like shape by partially fusing the top surface side of the filler padding or the polyurethane molding or partial-ly laminated filler padding.
- Furthermore, although not illustrated, according to this invention, portions for a-ttaching the backing board 3 onto the body o~ a vehicle door can be directly welded on the backing board 3 itself, but these portions have been hitherto fixed on the backing board 3 by screws or other means.
The above-mentioned technique is not to be limited to a door pad, but it can be widely applied to vehicle seats, other interior parts for vehicles, furnitures or the likes.

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Whlle the invention has been shown and described with respect to the particular embodiments of door pad, it wi.ll be understood that various modification may be effected without departing from the spirit and scope of the concepts of this invention~

Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PROPERTY
OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A door pad manufactured by ultrasonic welding, which comprises a laminate consisting of a surface layer material, a polyurethane moulding, or other filler padding, made of normal, untreated, polyurethane, and a backing board, desired portions of said laminate being fusion-bonded by heat produced therein by ultrasonic vibration, in which the filler padding or moulding is partially fused in the longitudinal (depth) direction between a weld portion and the backing board to weld the surface layer to the filler padding.

2. A door pad according to claim 1, in which button-shaped portions are formed on or welt-shaped members are welded to the surface layer.

3. A door pad according to claim 1 or 2, in which the terminating ends of the surface layer are welded on the back side of the backing board, enclosing the backing board.

4. A method for manufacturing a door pad by the application of ultrasonic waves, which comprises the steps of putting a surface layer material, a polyurethane moulding or other filler padding made of normal, untreated, polyurethane and a backing board, in a laminated state, between ultrasonic machining horns and ultrasonic machining horn rests, and applying ultrasonic vibration to desired portions of said laminate by the ultrasonic machining horns, while a force is being imparted thereon, whereby the desired portions of the laminate are fusion-bonded by heat produced therein, in which said filler padding or moulding is fused partially in the longitudinal (depth) direction between a weld portion and the backing board, thereby to weld the surface layer to the filler padding.

5. A method according to claim 4, in which button-shaped portions are formed on the top surface of the surface layer or welt-shaped members are welded on the surface layer.

6. A method according to claim 4 or 5, in which the terminating ends of the surface layer are welded on the back side of said backing board, enclosing the backing board.