Note: Descriptions are shown in the official language in which they were submitted.
!,32 F~
1 3 1 4066
1METHOD OF AND APPARATUS FOR FUSING
2RESIN MEMBERS SUCH AS BUMPER BEAM AND BUMPER FACE
3OF AUTOMOBILE suMpER
BACKGROUND OF THE INVENTION
6 1. Field oE the Invention:
7 The present invention relates to a method of and
8 an apparatus for joining resin parts, and more particularly
9 to a method of and apparatus for fusing resin parts or
members such as the bumper beam and bumper face of an
11 automobile bumper.
12 2. Description of the Relevant Art:
13 Automobile bumpers generally comprise an outer
14 bumper face and an inner bumper beam joined to an inner
surface of the bumper face for reinforcing the same, the
16 bumper being being adapted to be mounted on an autombile
17 body. The bumper face and beam have heretofore been heavy
18 and liable to produce rust since they are made of pressed
19 steel sheet.
Thermoplastic resin such as polypropylene or
~21 polyethylene is employed to make relatively large products
22 inasmuch as it is lightweight and highly rigid. Where
; 23 ~automobile bumpers are constructed of such thermoplastic
24 resin, they are Iightweight and less apt to develop rust.
For injectian molding a relativley large resin component~
26 it~ i5 general to form smaller~ divided members separately
27 and then join the formed members subsequently into the
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1 31 406~
1 resin component so that molds required are not increased in
2 size and molded members can easily be removed from the
3 molds. It is preerable to form an automobile bumper by
4 molding a bumper beam and a bumper face separately.
Various methods are available to join the bumper beam and
6 face to each other. For example, they may be joined by
7 adhesive, or interconnected by mechanical parts such as
8 screws. Since they are made of thermoplastic resin, they
9 may be joined by heating and fusing their joining surfaces
with panel heaters held thereagainst and then pressing the
11 fused joining surfaces to each other to connect the members
12 integrally to each other.
13 The bumper beam is required to be higher in
14 rigidity since it supports the bumper face, and hence
should be reinforced by another member. There has been
16 developed a plastic composite material known as stampable
17 resin sheet, which can be stamped to a desired shape. One
1~ known such stampable resin sheet is a glass Eiber
19 reinforced resin or plastic (hereinafter referred to as
FRP) sheet comprising glass fibers impregnated with
21 thermoplastic resin such as polypropylene or polyethylene.
22 This sheet has a thickness ranging from 2 to 4 mm. It is
23 preferable to form the above divided members by stamping a
24 lamination of such sheets. The resin sheet thus formed is
as rigid as steel sheet.
26 Before stamping a lamination of FRP sheets, each
27 of the sheets must be fused by a heater or in a heated
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1314066
l atmosphere. However, since the thermal conductivity of the
2 resin is small, iE the sheet were quickly heated, the
3 surface layer thereof would reach a degradation temperature
4 Td before the inside portion oE the sheet would reach a
melting temperature, resulting in degradation of the sheet.
6 Therefore, it is current practice to heat an FRP sheet
7 gradually in a relatively low-temperature atmosphere so
~ that the temperature Ti' of the inside area o the sheet
9 reaches a resin melting temperature Tm before the
temperature Ts' of the surface layer of the sheet reaches a
11 resin degradation temperature Td, as shown in FIG. 28 of
12 the accompanying drawings. The graph of FIGo 28 has a
13 horizontal axis representing heating time t and a vertical
14 axis representing resin temperature Tp. It takes 4 minutes
and 30 seconds to reach a heating completion time tc after
16 a heating starting time tO. Accordingly, the efficiency of
17 the heat treatment of the sheet is low r and so is the
18 production rate for stamping the lamination of FRP sheets.
19 The processes for joining resin members using
adhesive of mechcanical parts are complex and have a low
21 production efficiency. The process for joining resin
22 members through fusion is more preferable.
23 ~ven where the latter fusion process is employed,
24 however, it is somewhat difficult to have large joining
areas of the bumper face and face. Moreover, fused resin
26 may be attached to the panel heaters, and foreign matter
~ 27 such as carbides may be trapped in the fused areas of the
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1 bumper face and beam, resulting in a reduced degree of
2 bonding strength. One solution to these problems is to
3 coat the surfaces of the panel heaters with Teflon.
4 However, since Teflon layers are li!{ely to peel off, the
panel heaters have to be replaced periodically. In case
6 the joining surfaces of the bumper beam and face are of
7 different shapes, different heaters should be used for
8 heating the jointing areas of different shapes. With an
9 increased number of heaters used, the entire fusing
apparatus is complex in structure. Furthermore, divided
11 members formed by stamping FRP sheets contain ~ibers even
12 at the joining surEaces, which become short of fusible
13 resin and tend to develop insuEficient joining forces.
14 The present invention has been made in view of
the aforesaid problems oE the convetional automobile
16 bumpers, the process of stamping FRP sheets, and the
17 process oE fusing together bumper beam and face as resin
18 parts.
19 SUMMARY OF THE INVENTION
It is an object of the present invention to
21 provide an automobile bumper of thermoplastic resin which
22 is lightweight, highly rigid, and does not require another
23 member for reinforcing a bumper beam.
24 ~nother object of the present invention is to
provide a method of heating an FRP sheet highly efficiency
26 so that a subsequent process of stamping a lamination of
27 FRP sheets can be effected with increased production
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1 31 4066
efficiency.
2 Still another object o the present invention is
3 to provide a method of fusing thermoplastic resin parts
4 such as bumper beam and face of an autombile bumper while
preventing foreign matter from being trapped in fused areas
6 Of the parts and allowing heaters to be used for a long
7 periof of time.
8 To achieve the above objects~ there is provided
9 an automobile bumper comprising an outer bumper face, a
bumper beam joined to an inner surface oE the bumper face
11 for reinforcing the bumper face, the bumper beam being
12 adapted to be mounted on an automobile body, the bumper
13 face and the bumper beam comprising parts molded of
14 thermoplastic resin, the bumper beam including at least two
members of thermoplastic resin having joining surfaces to
16 be fused to each other, and flanges for forming beam
17 flanges together when the members are fused to each other,
18 the beam flanges being fused to an inner surface of the
19 bumper face.
There is also provided a method of heating an FRP
21 sheet to be stamped, comprising the step of continuously
22 heating the FRP sheet in an atmosphere having a temperature
23 sdccessively lowered from a temperature higher than a resin
24 ~melting temperature at which a resin of the FRP sheet is
melted so that the entire FRP sheet is increased through
26 successive heating stages to a temperature between the
27 resin melting temperature and a resin degrada-tion
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1 31 4066
1 temperature at which the resin of the FRP sheet is
2 degraded.
3 There is also provided a method of fusing at
4 least two parts of thermoplastic resin to each other,
comprising the steps of bringing heaters into close
6 proximity with joining surfaces to be fused of the parts
7 with a prescribed spacing therebetween for melting the
8 joining surfaces, and pressing the melted joining surfaces
g against each other to fuse the parts together. ~t least
one of the at least two parts comprises an FRP product made
11 of glass fibers reinforced with a thermoplastic resin, the
12 joining sur~aces of the FRP product having a plurality of
13 projections containing the thermoplastic resin only, the
14 projections being melted when the parts are fused together.
The above and further objects, details and
16 advantages of the present invention will become apparent
17 from the following detailed description of preferred
18 embodiments thereof, when read in conjunction with the
19 accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
21 FIG. 1 is a perspective view of a bumper face of
22 thermoplastic resin and a bumper beam of thermoplastic
23 resin according to the present invention, before they are
24 fused together;
FIGS. 2 through 4 are views explaining a heating
26 method for stamping one of two members of the bumper beam,
27 FIG. 2 showing a device for heating an FRP sheet, FIG. 3
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1 being a graph of temperatures of the FRP sheet in
2 respective steps of operation of the heating device, FIG. 4
3 schematically show.ing steps of the heating process;
4 FIG. 5 is a graph o temperatures oE an FRP sheet
in various steps of a heating method according to another
6 embodiment of the present invention;
7 FIGS. 6 and 7 are enlarged plan and fragmentary
8 cross-sectional views of a fused surface of the FRP bumper
9 beam;
FIGS. 8 through 13 are elevational views of an
11 apparatus according to the present invention for fusing the
12 bumper face and beam shown in FI~. 1, the views showing
13 successive steps of operation of the apparatus;
14 FIG. 14 is a cross sectional view of a heater in
the fusing apparatus;
16 FIG. 15 is a cross-sectional view of an
17 automobile bumper according to another embodiment of the
18 present invention;
19 FIG. 16 is an exploded cross-sectional view of a
bumber beam of the bumper shown in FIG. 15;
21 FIGS. 17 through 21 are elevational views of an
22 apparatus according to the present invention for fusing
23 together members of the bumper beam of FIG. 16, FIG. 17
24 being a front elevational view, partly in cross section, of
; ; 25 the fusing apparatusl FIGS. 18 through 21 being side
26 elevational views of the fusing apparatus showing the
27 successive steps of operation thereof;
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1 31 4066
1 FIG. 22 is a front elevational view of the fusing
2 apparatus;
3 FIG. 23 is a side elevational view of the fusing
4 apparatus;
FIG~ 24 is a plan view of the fusing apparatus;
6 FIGS. 25A through 25D are views showing a process
7 vf clamping the bumper face;
8 FIGS. 26 and 27 are views sho~ing respective
9 steps of melting and fusing the joining surfaces of the
bumper face and beam; and
11 FIG. 28 is a graph showing temperatures of an FRP
12 sheet in various steps of a conventional heating method.
13 DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
14 Bumper beam and face of a front automobile bumper
will hereinafter be described as thermoplastic resin parts
16 or components.
17 As shown in FIG. 1, a front automobile bumper 50
18 comprises an outer bumper face 1 and an inner bumper beam 2
19 joined to an inner surface of the bumper face 1 to
reinforce the same. The bumper beam 2 is thermally fused
21 to the inner surEace of the bumper face 1 by a method
~22 described later on. The bumper face 1 is formed by
23 ~ injecting molding thermoplastic resin such as polyethylene
24 or polypropylene, for example. The bumper beam 2 is formed
by stamping glass fiber reinforced resin or plastic (FRP).
26 The bumper face 1 has a grille 3 in its front lower portion
27 and opposite side ends 4 directed backwards at a
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1 31 4066
1 substantically right angle. The bumper beam 2 comprises
2 two members or parts 5, 6. The member 5 has a cross-
3 sectional shape including upper and lower shallow channels
and a single, relatively deep central channel. The member
6 haa a cross-sectional shape having a wide central
6 channel. Flat front surfaces 5a, 5b of the upper and lowe
7 channels and a flat front surface 5c of the central channel
8 of the member 5 are thermally fused to corresponding flat
9 rear surfaces 6a, 6b, 6c of the member 6 by a method
described later. The bumper beam 2 is constructed of the
11 members 5, 6 thus thermally fused together. With the
12 members 5, 6 fused together, upper and lower flanges 5d, 5e
13 of the member 5 lie flush with upper and lower flanges 6d,
14 6e, respectively, of the member 6, jointly forming upper
and lower flat flanges 2a, 2b of the bumper beam 2. The
16 flanges 2a, 2b are thermally fuxed to a rear surface la of
17 the bumper face 1, thus completing the bumper 50.
~18 The member 5 of the bu~per beam 2 is formed in
19 the following manner (since the member 6 is also formed in
the same manner, it will not be described in detail):
Zl FIG. 2 schematically shows a heating device in
~22 which a plurality of FRP sheets 5i are placed on a feeder
23 comprising wire ropes 8 kept taut in a heating furnace 7
; 24 ~FIG. 4). Each of the FRP sheets 5i has a prescribed width
and a prescribed length. The FRP sheet 5i comprises glass
; 26 fibers impregnated with thermoplastic resin such as
7 polypropylene or polyethylene, for example, and has a
g
:
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1 31 4066
l thickenss ranging from 2 to 4 mm. Heaters 7a, 7b for
2 producing ~ar infrared rays are disposed in the heating
3 furnace 7 above and below the resin sheets 5i in spaced
4 relation thereto for heating the sheets 5i hetween the
heaters 7a, 7b. When the sheets 5i are heated, the surface
6 layers and inner ~reas thereof are substantially uniformly
7 melted. ThereaEter, the sheets 5i are stacked into a
8 lamination, placed in dies, and stamped into the beam
9 member 5.
The resin sheets 5i are heated in a plurality of
11 regions, i.e., three zones or stages Zl, Z2, Z3.
12 FIG. 3 shows the relationship between heating
13 time t and resin temperature Tp, the heating time being
14 divided into three zones Zl, Z2, Z3. FIG. 5 schematically
shows such a three-step heating process. Denoted at Td in
16 FIG. 3 is a resin degradation temperature and Tm a resin
17 melting temperature.
18 The resin sheets 5i are fed stepwise by the
l9 feeder mechanism 8 from a standby position Z0 into the
heating furnace 7 in which the sheets 5i are placed in the
21 quick heating zone Zl.
22 In the first zone Zl, the resin sheets 5i are
23 quickly heated for about 40 seconds in an atmosphere at a
24 temperature of about 400C. As a result, the surface layer
temperature Ts of the resin sheets 5i is rapidly inreased
26 as shown in FIG. 3 at a rate higher than the conventional
27 rate. The temperature Ti of the inner area of the resin
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1 31 4066
1 sheets 5i is also quickly increased at a rate lower than
2 that of the surface layer temperature Ts. The heating in
3 the intensive heaing zone Zl is finished beEore the
4 temperatures Ts, Ti reach the resin melting temperature Tm.
The sheets 5i are then fed stepwise into the
6 second medium heating zo~e Z2, in which they are heated in
7 an atmosphere at about 300C or more specifically at 320C
8 in this ernbodiment continuously for 40 seconds, for
9 example. The surface layer temperature Ts oE the sheet 5i
exceeds the melting temperature Tm, but the inside
11 temperature Ti does not reach the melting temperature Tm
12 though it is higher than the conventional inside
13 temperature, as shown in FIG. 3. The heating in the medium
14 heating zone Z2 is finished before the surface layer
temperature Ts reaches the degradation temperature Td.
16 Thereafter, the sheets 5i are fed stepwise in-to
17 the third less intensive heating zone Z3, in which they are
18 heated in an atmosphere at about 250C slightly lower than
19 the degradation temperature Td continuously for ~0 seconds,
~or example. The sur~ace layer temperature Ts of the sheet
21 5i keeps above the melting temperature Tm, and the inside
22 temperature Ti exceeds the melting temperature Tm.
23 In the above heating process, the surface layer
24 and inside area of each oE the resin sheets 5i are melted.
The sheets 5i are stacked in a zone Z4 as shown in FIG. 4,
26 and then placed into dies by which they are stamped into
27 the member 5. ~lthough three sheets 5i are shown as being
1 3 1 4066
1 stacked, the number of stacked sheets may be varied
2 dependent on the member into which the sheets are to be
3 stamped. The total heating time is ?. minutes, which is
4 about half the conventional hea-ting time of 4 minutes and
30 seconds as shown in F~G. 28.
6 The resin sheets 5i are continuously heated in
7 atmospheres of temperatures successively lower than a
8 temperature (400C) lower than the resin melting
9 temperature Tm (about 180C). Thus, the heating time is
much shorter than the heating time of the conventional
11 method as shown in FIG. 28 by which a sheet is hetaed in a
12 single atmosphere at a relatively low temperature. The
13 efficiency of the heating process is increased, and so is
14 the production efficiency of the process of stamping the
stacked sheets.
16 While the sheets 5i are heated separately in the
17 three zones Zl, Z2, Z3, they may be heated in two zones.
18 FIG. 5 shows the relationship between the sheet heating
19 time t and the sheet temperature Tp according to such a
~modification. In this modification, the sheets 5i are
21 heated Eor about 50 seconds in an atmosphere at about 400C
22 in an intensi~e heating zone 21'. Then, the sheets 5i are
23 heated Eor about 70 seconds in an atmophere at about 250C
24 in a less intensive zone Z3'. The surface layers and inner
areas of the sheets 5i are substantially uniformly heated
.
26 in the total time of 2 minutes. The same advantages as
27 those of the heating process using the three zones Zl - Z3
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1 31 4066
1 are offered by the modified heating process.
2 When the members 5, 6 are stamped, their surfaces
3 5a, 5c, 5b and 6a, 6c, 6b to be Eused are provLded with a
4 number of projections, and the flat surfaces 5d, 5e and 6d,
6e oE the members 5, 6 which jointly form the surfaces 2a,
6 2b of the bumper beam 2 to be fused to bumper face 1 are
7 also provided with a number of projections, in the manner
8 described below. FIGS. 6 and 7 show, by way of example,
9 the fusing surface 5a of the member 5 of the bumper beam 2,
which has a number of projections formed thereon. As shown
11 in FI. 7, the member 5 is formed by impregnating glass
12 fibers F with resin P.
13 A number of projections 5j are formed on the
14 fusing surface 5a of the member 5. The projections 5j do
not contain fibers F but contain only resin P. As
16 illustrated in FIG. 6, the projections 5j are formed in a
17 mosaic pattern with grooves 5k defined therebetween. As
18 shown in FIG. 7, each of the projections 5j has a width wl
19 shorter then the fibers F, the width wl being in the range
of from 3 to 10 mm. Each of the grooves 5k has a width sl
21 smaller than the thickness of the fibers F, the width sl
22 ranging from 0.5 to 1.0 mm. Thus, the fibers F are
23 prevented from entering or being exposed in the grooves 5k.
24 The height hl of the projectlons 5j, and hence the depth of
the grooves 5k are in the range of 0.5 to 1.0 mm so that a
26 sufficient fused layer is formed when the sheet is fused.
27 A method of thermally fusing the bumper beam 2
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1 3 1 4066
1 and the bumper face 1 as clivided components oE thermo-
2 plastic resin, and an apparatus for carrying out such a
3 method will be described with reference to FIGS. 8 through
4 13.
As shown in FIG. 8, a fusing apparatus generally
6 designated by the reference numeral 10 has a base 11 on
7 which laterally spaced rai~s 12, 13 are mounted. The rails
8 12 support thereon a first movable carriage 14 on which the
9 beam members 5, 6, not yet joined, are placed, the first
movable carriage 14 being movable on the rails 12. The
11 rails 13 support thereon a second movable carriage 15 on
12 which the bumper face 1 is placed, the second movable
13 carriage 15 being movable on the rails 13. The second
14 movable carriage 15 has a plurality of laterally swingable
arms 16 having respective vacuum pads 17 disposed on the
16 inner sides of their upper ends for fixing the bumper ace
17 1 under suction. The second movable carriage lS moves on
18 the rails 13 with the bumper face 1 fixedly positioned by
19 the vacuum pads 17.
On the base 11, there are vertically disposed a
21 plurality of posts 18 positioned out of interference with
22 the path of movement of the first movable carriage 14
23 supporting the beam 2 thereon and also out of intererence
24 with rails 29, described later. A support plate 19 is
Z5 attached to the upper ends of the posts 18 and supports
26 thereon a first cylinder unit 20 and a second cylinder unit
27 21. The first and second cylinder units 20, 21 serve as
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1 first and second lifting devices, respectively. The Eirst
2 cyl.inder unit 20 has a rod ~Oa con~ractably extending
3 downwardly and supporting a first clamp 22 on its lower
4 end. The second cylinder unit 21 has a rod 21a
contra~tably extending downwardly and supporting a second
6 clamp 23 on its lower end. ~ plurality of arms 24
7 supporting a heater 25 between their lower ends depend from
8 the support plate 19, the heater 25 extending in a
9 direction normal to the sheet of FIG. 8. The arms 2~ and
the heater 25 are positioned out of interference with the
11 path of vertical movement of the second clamp 23 caused by
12 the second cylinder unit 21.
13 As shown in FIG. 14, the heater 25 comprises a
14 tube 26 of quartz having substantially the same
longitudinal dimension as those of the beam members 5, 6,
16 and a coiled electric heater wire 27 inserted in the tube
17 26. The tube 26 can be coupled to another tube and can
18 flexibly be bent. The tube 26 may be made of metal. The
19 heater wire 27 is preferably a Nichrome wire~
A plurality of post5 28 are vertically disposed
21 on the base 11 outside of the rails 12, 13, the posts 28
22 being shorter than the posts 18. Laterally extending rails
23 29 are mounted on the upper ends of the posts 28, and
~4 mobile bodies 30 are movably mounted respectively on the
rails 29. One of the mobile bodies 30 supports thereon a
26 third cylinder unit 31 having a rod 31a contractably
27 extending downwardly with an arm 32 attached to -the lower
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1 3 1 4066
1 end thereof. The rail 29, the mobile body 30, the cylinder
2 unit 31, and the arm 32 constitute one assembly, and
3 another identical assembly is positioned behind the
4 illustrated assembly. Four heaters 33, which are identical
in str~cture to the heater 25, extend between the arms 32
6 in a direction normal to the sheet of FIG. 3. A vertically
7 swingable pallet 34 is attached between the mobile bodies
8 30 for supporting the bumper beam 2. The pallet 34 extends
9 between the rails 29 and has a longitudinal dimension
larger than that of the bumper beam 2. The heaters 33 have
11 a longitudinal dimension that is substantially the same as
12 that of the bumper face 1.
13 The process of thermally fusing the bumper beam 2
14 and the bumper face 1 together using the fusing apparatus
10 will be described below. The first movable base 14 and
16 the second movable base 15 are driven at a prescribed
17 sequence by a driver mechanism (not shown), and the
18 cylinder units 20, 21, 31 are controlled at a prescribed
19 sequence by a control mechanism (not shown). For the sake
of brevity, these driver and control mechanisms will not be
21 described in detail as they have no direct bearing on the
22 present invention. The first clamp 22, the second clamp
23 23, and the arm 32 are vertically moved by extension and
24 contraction of:the first, second, and third cylinder units
20, 21, 31, respectively~ Therefore, operation of the
26 cylinder units 20, 21, 31 will not be described.
27 (A) First, the members 5, 6 which are not yet
,
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1 31 4066
1 joined are set on the first movable base 14 in a stac~ed
2 condition, as shown in FIG. 8. Then, the Eirst movable
3 base 14 is moved to the right (FIG. 8) and then stopped
4 directly below the first clamp 22.
(s) ThereaEter, the rod 20a of the Eirst cylinder
6 unit 20 is extended to lower the Eirst clamp 22 to the
7 position of FIG. 9. The clamp 22 engages in the three
8 channels of the member 5 of the bumper beam 2 to grip the
g member 5. The rod 20a is then contrcted to lift the Eirst
clamp 22 and hence the member 5 therewith.
11 tC) The mobile bodies 30 are moved to the left
12 and stopped in a position between the members 5, 6, as
13 shown in FIG. 10. Before the mobile bodies 30 are moved,
14 the rod 31a has been contracted to lift the arm 32 and the
pallets 34 ha~e been swung upwardly.
16 (D) Then, the first cylinder unit 20 and the
17 third cylinder units 31 are extended to lower the member 5
18 and the arm 32 to the position oE FIG. 11. The heaters 33
19 are now positioned between the flat surfaces 5a, 5b, 5c of
the member 5 and the flat surfaces 6a, 6b, 6c of the member
21 6. The heaters 33 and the flat surfaces 5a, 5b, 5c and 6a,
22 6b, 6c are preferably spaced a distance ranging from 5 to
23 15 mm, and the heaters 33 are preferably heated to a
24 temperature ranging from 500 to 600C. The flat surfaces
Sa, 5b, 5c, 6a, 6b, 6c are melted by infrared rays emitted
26 from the heaters 33. Since the flat surfaces have
~ 27 projections, as described above, they are well melted at an
:
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1 3 1 4066
1 increased rate.
2 (E) Subsequently, the first clamp 22 and the arm
3 32 are elevated, and then the mobile bodies 30 are moved to
4 the right to displace the arm 32 out o~ the space between
the members 5, 6. Immediately thereafter, the member 5
6 with the lower flat surfaces 5a, 5bl 5c melted is lowered
7 into contact with the melted upper surfaces 6a, 6b, 6c of
8 the member 6l as shown in FIG. 12. The member 5 is pressed
9 against the member 6 by -the first cylinder unit 20. The
members 5, 6 are integrally fused to each other into a
11 bumper beam 2. The pallets 34 are closed right after the
12 mobile bodies 30 are moved rightwardly.
13 (F) In the position of FIG. 12, the completed
14 beam 2 is still gripped by the first clamp 22. The first
clamp 22 and the bumper beam 2 gripped thereby are lifted
16 above the mobile bodies 30, which are then moved to a
17 position directly below the first clamp 22, i.e., the
18 bumper beam 2. Then, the bumper beam 2 is lowered onto the
19 pallets 34 of the mobile bodies 30. The bumper beam 2 is
released from the first clamp 22 and placed on the pallets
21 39. Thereafter, the first clamp 22 is elavated, as shown
22 in FIG. 13.
23 (G) The mobile bodies 30 is moved to a position
24 directl~ below the second clamp 23, which is then caused to
descend to grip the bumper beam 2, as illustrated in FIG.
26 8. Prior to this, the bumper face 1 has been set on the
27 second movable base 15. The second clamp 22 is lifted
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1 until the flat flanges 2a, 2b of the bumper beam 2 are
2 positioned near the heaters 25 on the lower end of the arms
3 24. The Elat flanges 2a, 2b and the heaters 25 are spaced
4 5 to 15 mm from each other. Simultaneously, the second
movable base 15 is moved ~o the left until the bumper Eace
6 1 i3 positioned directly beneath the arm 32. The arm 32 is
7 lowered to bring the heaters 33 into confronting relation
8 to the inner surface la of the bumper face 1. At this
9 time, the arms 16 are spread laterally to keep the heaters
33 and the inner surface la of the bumper face 1 spaced
11 apart 5 to 15 mm from each other, as shown in FIG. 9.
12 (H) In the position of FIG. 9, the heaters 25, 33
13 are energized to melt the flat surfaces 2a, 2b of the
14 bumper beam 2 and the inner surface la of the bumper face
1. During this melting period, the members 5, 6 of a next
16 bumper beam 2 are moved to the position below the first
17 clamp 22 by the first movable base 14, and gripped by the
18 first clamp 22, as described above.
19 (I) After the flat surEaces 2a, 2b and the inner
surface la have been meltedr the arm 32 is lifted, and the
21 moblle bodies 30 are moved to the left. Therefore, the
22 pallets 34 and the arm 32 are displaced out of the space
23 between the bumper beam 2 and the bumper face 1 and into
24 the position between the next members 5, 6, as shown in
FIG. 10.
26 ~ (J) Then, the second clamp 23 is lowered to
27 position the bumper beam 2 inside of the bumper face 1.
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1 3 1 406~
1 The arms 16 are moved toward each other to bring the inner
2 surface la of the bumper face 1 against the flat surfaces
3 2a, 2b of the bumper beam 2, as illustrated in FIG. 11.
4 The bumper face 1 is pressed against the bumper beam 2,
S thus completing a bumper 50.
6 (K) ThereaEter, the second clamp 23 is released
7 out of engagement with the bumper 50 and lifted to the
8 position of FIG. 12.
9 (L) The second movable base 15 is moved to the
right as shown in FIG. 13. The bumpber 50 is then
11 dismounted from the second movable base 15, which will
12 tHereaEter be supplied with a next bumper face 1.
13 The above proc~ss steps (G) through (L~ are
14 carried out simultaneously with the process steps (A)
through (F).
16 Since the bumper beam 2 and the bumper face 1 are
17 made of thermoplastic resin, the bumper 50 is highly rigid
18 and lightweight. The rigidity o~ the bumper 50 is high
19 because the bumper beam 2 is constructed of the two FRP
members 5, 6 fused integrally together, and also because
21 the central surface 5c and side surfaces 5a, 5b of the
22 member 5 fused respectively to the central surface 6c and
23 side surfaces 6a, 6b of the other member 6 and the flanges
24 2a, 2b of the members 5, 6 are fused to the inner surface
la of the bumper face 1~
26 The heaters 33 are spaced 5 to 15 mm from the
surfaces 5a, 5b, 5c and 6a, 6b, 6c of the members 5, 6 when
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''. ' ' . ~ .
1 31 4066
1 they are melted in the step (D). ThereEore, melted resin
2 is not attached to the heaters 33 and no foreign matter is
3 trapped in the melted surfaces of the members 5, 6.
4 Therefore, it is not necessary to coat the surfaces of the
heaters 33 with Teflon, and the heaters 33 can be used for
6 a long period of time. As a result, automobile bumpers 50
7 can successively be manufactured with high efficiency.
8 Likewise, the heaters 25, 33 are spaced similarly from the
9 surfaces 2a, 2b, la o~ the bumper beam 2 and the bumper
face 1 when they are melted in the step (H), resuling in
11 the same advantages as described above.
12 The joining surfaces 5a, 5b, 5c and 6a, 6b, 6c of
13 the members 5, 6 of the bumper beam 2 are melted commonly
14 by one set of heaters 33. Therefore, -the number of heaters
for melting these joining surfaces is reduced. Since these
16 heaters 33 are also used to melt the inner surface la of
17 the bumper face 1, the number of the heaters in the heating
18 apparatus 10 is reduced. ~s a consequence, the number of
19 parts of the heating apparatus 10 is reducedl making the
heating apparatus 10 compact.
2L The joining surfaces 5a, 5b, 5c and 6a, 6b, 6c fo
22 the members 5, 6 of the bumper beam 2, the joining surfaces
23 Sd, 6d (i.e., 2a), and the joining surfaces 6e, 6e ti.e.,
24 2e) have a plurality of projections containing only resin
P, as shown in FIGS. 6 and 7. Therefore, these joining
26 surfaces contain a necessary and sufficient amount of resin
27 when they are fused togethert and can be fused with a
: ~
~ ~ - 21 -
1 3 1 4066
1 sufEicient bonding strength.
2 In the above embodiment, the front automobile
3 bumper S0 is made of thermoplastic resin. ~owever, the
4 present invention is also applicable to a rear automobile
bumper. While the bumper beam 2 and -the bumper face 1 are
6 thermally fused together in the illustrated embodiment, any
7 other parts made of thermoplastic resin can be thermally
8 fused by the method of -the present invention.
9 A method of fusing parts of thermoplastic resin
according to another embodiment of the present invention
11 will be described with reference to FIGS. 15 through 21.
12 A bumper beam 152 of an automobile bumper 150
13 made of thermoplastic resin as shown in FIG. 15 will be
14 described by way of example as a thermoplastic resin part
or member. The automobile bumper 150 comprises a bumper
16 face 151 and the bumper beam 152, which are elongate
17 members of thermoplastic resin. The bumper face 151 has a
18 body 151d of an inverted channel shape including an upper
19 portion 151a, a front portion 151b, and a lower portion
151c. From the lower portion 151c, there extends a skirt
21 151e inclined rearwardly and downwardly and having air
22 slits 151f. The bumpber beam 152 comprrises members 153,
23 154 of FRP, as shown in FIG. 6. The members 153, 154 have
24 joining surfaces 153a, 153b and 154a, 154b, respectively,
which are fused to each other. The members 153, 154 have
26 flanges 153c, 153d and 154c, 154d, respectively, bent 90
27 from the outer edges of the joining surfaces 153a, 153b and
:
- 22 -
.. . . .
1 31 406~
1 154a, 154b. These flanges 15~3Cr 153d and 154c, 154d serve
2 as fusing surfaces to be fused to the inner surEace of the
3 bumper face 151. Thus, the joining surfaces 153a, 154a and
4 153d, 154d of the members 153, 154, and the bent flanges
153c, 154c and 153d, 154d thereof jointly form joining
6 portions of a T-shaped cross section of the bumper beam 152
7 which are to be joined to the bumper face 151. The bumper
8 beam 152 is of a substan-tially box-shaped cross section for
9 increased rigidity. Where the bumper beam 152 is
constructed of a single molded member rather than the two
11 members 153, 154, spaces Ul, ~2, U3 shown in FIG. 9 serving
12 as undercuts.
13 FIGS. 17 through 21 show a method of fusing
14 together the bumper beam members 153, 154 and an apparatus
for carring out such a method.
16 As shown in FIG. 17, a fusing apparatus 100 has
17 base 102 on which there are mounted rails 103 extending in
18 a back-and-forth direction normal to the sheet of FIG. 17.
19 The rails 103 are shown as extending laterally in FIGS. 18
through 21. The righthand side of FIGS. 18 through 21 is a
21 front side of the fusing apparatus 100, and the lefthand
22 side is a rear side thereof. A support base 104 supporting
23 a lower jig 106 is movably supported on thQ rails 103. On
24 the support base 104, there are supported the members 153,
154 of the bumper beam 105 with the substantially L-shaped
26 member 153 below the member 1540 The lower member 153 is
27 clamped on the lower jig 106. The jig 106 has vertical
1 31 4066
~ members 107, 108 spaced in the direction normal to the
2 sheet of FIG. 17 and having upper edges 107a, 108a engaging
3 the inner sides o~ the flanges 153c, 153d of the lower
4 member 153. Therefore, slight deformation of the lower
member 153 which may be introduced upon stamping is
6 corrected by these jig members 107, 108. The vertical
7 members 107, 108 have longitudinal shapes complementary to
8 the normal shape of the lower member 153 and elongated in
9 the lateral direction in FIG. 17. Positioning pins 109
which are laterally spaced from each other are disposed
11 behind the front vertical member 108 of the lower jig 106.
12 The positioning pins 109 serve to position the upper member
13 154 placed on the lower member 153 in the direction normal
14 to the sheet of FIG. 17 for keeping the members 153, 154
relatively positioned while they are being fused to each
16 other.
17 A shift cylinder 110 (FIG. 18) is disposed behind
18 the support base 104 and has a rod llOa coupled to a rear
19 portion of the support base 104. The support base 104 is
movable back and forth by the rod llOa in response to
21 operation of the shift cylinder 110.
; 22 As illustrated in FIG. 17, an upper jig support
23 frame 113 in the form of an inverted channel as viewed in
24 front elevation comprises two vertical frame members 111
disposed one on each side of the base 102 and a horizon-tal
26 frame member 112 interconnecting the upper ends of the
27 vertical frame members 11~. An upper jig support base 114
: - 24 -
1 3 1 4066
1 is vertically movably supported in the support Erame 113.
2 The support base 114 is ver-ticaly guided by guides 116
3 coupled to its opposite ends and slidably fitted over
4 vertical guide posts 115. The opposite ends of the suport
base 114 are coupled to rods 117a of pressure cylinders 117
6 vertically disposed on the lateral sides of the base 102.
7 The center of the support base 114 is coupled to a rod 118a
8 depending from a pressure cylinder 118 vertically mounted
g on the center of the horizontal frame member 112 o~ the
support frame 113. The upper jig support base 114 supports
11 an upper jig 119 having depending members 120, 121 spaced
12 from each other in the direction normal to the sheet of
13 FIG. 17. The members 120, 121 of the upper jig 119 are
14 vertically longer and shorter, respectively, so that their
lower ends 120a, lOla will engage the inner sides of the
16 flanges 154c, 154d of the upper member 154. The members
17 120 which are complenmentary in shape to the normal shape
18 of the upper member 154 e~tend laterally in FIG. 17.
19 Denoted at 122 in FIG. 18 are hooks mounted on the vertical
frame members 111 and engageable with the support base 114
21 for preventing the upper jig 119 from falling when the
22 upper jig 119 is lifted and stored. Denoted at 123 in FIG.
23 17 is an auxiliary clamp jig for additionally clamping the
24 upper beam member 154, and 133 an auxiliary clamp jig for
additionally clamping the lower beam member 153.
26 Rails 124 extending in the direction normal to
27 the sheet of FIG. 17 are positioned one on each side of the
1 31 ~066
1 lower support jig base 104 on the base 102. Slide guides
2 126 on the lower ends of laterally spaced support frames
3 125 for a heater 130 (described later) are movable mounted
4 on the rails 124, respectively. The support frame 125 i5
S coupled to a rod 127a of a heater shifting cylinder 127
6 mounted on the base 102~ so that the support frame 125 is
7 bodily movable back and forth. ~ cylinder 128 (FIG. 18)
8 for vertically moving the heater 130 is vertically mounted
9 on the support frame 125 and has a rod 128a to which a heat
support base 129 is coupled. The heater 130 is supported
11 on the heater support base 129. As shown in FIG. 17, the
12 heater 130 extends laterally beyond the length of the upper
13 and lower beam members 153, 154 and includes four front and
14 rear, upper and lower heater elements 130a, 130b, 130c,
130d extending along the front and rear joining surfaces
16 153a, 153b, 154a, 154b of the members 153, 154. Designated
17 at 131 in FIG. 17 is a sensor for detecting the temperature
18 of the heater elements 130a - 103d, and 132 a guide mounted
19 on the support frame 125 for vertically moving the heater
130.
21 A process of fusing -the beam members 153, 154 to
22 each other using the fusing apparatus 100 will be described
23 below. The lower jig support base 104, the upper jig
24 support base 114, and the heater support base 125 are
driven at a prescribed sequence by the cylinders 110, 118,
26 1~7, 128 controlled by a control mechanism (not shown).
Since the control mechanism is not closely related to the
- 26 -
.
.
1 3 1 4066
1 present invention, it will not be described below. In
2 addition, operation of the cylinders 110, 118, 127, 128
3 will not be described below unless required.
4 ~ irst, the members 153, 154 are set on the
lower jig 106 as shown in FIG. 18. At thie time, the upper
6 jig 119 is in an elevated position~ More specifically, the
7 support base 104 is moved forwardly along the rails 103 to
8 the rightmost set position. The worker then goes in front
9 of the lower jig 106, iOe., rightwardly of the lower jig
106, to set the lower memberf 153 on the lower jig 106.
11 Thereafter, the upper member 154 is placed on the lower
12 member 153 so that the joining surfaces 153a, 153b, 154a,
13 154b Eace each other. The upper member 154 is positionally
14 limited by the pin 109.
(ii~ Then, the support base 104 is retracted on
16 the rails 103 and stopped in the working position shown in
17 FIG. 19. The rods 117a of the cylinders 117 are
18 contracted, and the rod 118a of the cylinder 118 is
19 extended to lower the upper jig support base 114 and hence
the upper jig 119. Upon downward movement of the support
21 base 114 to its lower limit, the members 153, 154 are
22 gripped between the jigs 106j 119 and automatically clamped
Z3 forcibly thereby. The lower ends 120a, 121a of the members
24 120, 121 of the upper jig 119 are brought into forced
~25 engagement with the inner sides oE the flanges 154c~ 154d
26 of the upper member 154 placed on the lower member 153, as
27 shown in FIG. 19. Even iE the upper member 154 has
- 27 -
1 31 4066
1 slightly been deformed, it is forcibly corrected into its
2 normal shape by the members 120, 121 of the jig 119. The
3 member 154 is firmly held in position by the upper jig 119.
4 The intermediate portion oE the upper member 154 is held by
the auxiliary clamping jig 123. The lower member 153 is
6 depressed by downward forces from the upper member 154, so
7 that the upper ends 107a, 108a of the members 107, 108 of
8 the lower jig 106 forcibly engage the inner surfaces of the
9 flanges 153c, 153d of the lower member 153. ThereEore, any
slight deformation of the lower member 153 is forcibly
11 corrected by the configuration of the members 107, 108 of
12 the lower jig 106.
13 (iii) ThereaEter, the upper jig 119 holding the
14 upper member 154 is lifted to move the upper and lower
members 154, 153 relatively away from each other in the
16 vertical direction. The heater 130 which has been in a
17 standby position is postioned between the upper and lower
18 members 154, 153 in response to Eorward movement of the rod
19 127a of the cylinder 127. The lower member 153 has a step
which cooperates with the bumper face 151 in deEining a
21 space for receiving head lights and other members. The
22 heater 130 is lifted so that the lower heater elements
23 130a, 130b will not interfere with the step of the member
4 153. Thereafter, the heater 130 is moved forwardly by the
cylinder 127 and then lowered into close priximity with the
26 joining surfaces 153a, 153b of the lower member 153 with a
27 spacing, which may range from 5 to 15 mm, left
- 28 -
: :
- , , - , .
1 3 1 4066
1 therebetween. Concurrent with this, the upper member 154
2 is elevated and then lowered to bring the joining surfaces
3 154a, 154b into confronting relation to the upper heater
4 elements 130c, 130d of the heater 130 with a gap ranging
from 5 to 15 mm therebetween. The heater 130 and the
6 members 153, 154 are now positioned as shown in FIG. 20.
7 In the position of FIG. 20, the heater elements 130a - 130d
8 of the heater 130 are energized to heat and melt the
g joining surfaces 154a, 154b, 153a~ 153b oE the members 154,
153.
11 (iv) After the joining surfaces 154a, 154b, 153a,
12 153b of the members 154, 153 have been melted, the upper
13 member 154 is elevated. The heater 130 is lifted and then
14 retracted out of the position between the members 154, 153
which have been spaced vertically away from each other.
16 Thereafter, the upper jig 119 is lowered to place the upper
17 member 154 onto the lower member 153, so that the melted
18 joining surfaces 154a, 154b/ 153a, 153b are held against
19 each other, as shown in FIG. 21. The cylinders 117, 118
are operated to press the upper and lower members 154, 153
21 to fuse the joining surfaces 153a, 153b, 154a, 154b under
22 pressure. Unwanted deformation of the members 153, 154 is
23 further forcibly corrrected by such pressurized fusing
24 process.
(v) After the upper and lower members 154, 153
26 have been fused together into a bumper beam 152, the upper
27 jig 119 is lifted, leaving the bumper beam 152 on the lower
_ ~9 _
1 31 4066
1 jig 106. Then, the lower jig 106 holding the bumper beam
152 thereon is moved forwardly, and the bumper beam 152 is
3 removed.
4 Jn the above processing steps (i) through (v),
the beam members 1S3, 154 of thermoplastic resin are fused
6 together while they are being clamped by the upper and
7 lower jigs 119, 106 which are complementary in shape to the
8 normal shape of the members 153, 154. Therefore, slight
9 doformation of the members 153, 154 are forcibly corrected
by the shape of the jigs 119, 106. ~s a result, a product
11 o~ a normal shape can be produced. Since the fusing
12 process (i) through (v) can fully be automated, the fusing
13 operation can be performed reliably within a short period
14 of time, with the consequences that the required labor can
be saved, the rate of production can be increased, the
16 product quality can be improved and uniformized, and the
17 cost can be lowered. By replacing the upper and lower jigs
18 119, 106 and the heater 130 with other jigs and heater, the
19 fusing apparatus 100 can fuse resin members of other shapes
and hence is versatile.
21 In the above embodiment, the members 154, 153 are
22 fused while they are vertically placed one on the other.
23 However, the members to be fused together may be positioned
24 so as to be movable toward and away from each other
laterally or back and forth, and the heater may be disposed
26 between these members for heating and melting them.
27 A method of fusing the bumper beam 152 thus
- 30 -
.
. ~ . .
1 3 1 4066
1 constructed to the bumper face 151 and an apparatus for
2 carrying out such a method will be described below with
3 referenc~ to FIGS. 22 through 27.
4 As shown in FIG. 22, a fusing apparatus 200 has a
base Z03 supporting thereon a frame 202 comprising
6 laterally spaced vertical frame members 202a, and a
7 horizontal frame member 202b interconnecting the upper ends
8 of the vertical frame members 202a.
9 The lefthand side of FIG. 23 is the front of the
fusing apparatus 200 where the worker operates the
11 apparatus. The frame 202 is vertically disposed on an
12 intermediate portion of the base 202 in a direction normal
13 to the sheet of Fig. 22. A bumper face fixing jig base 204
14 is mounted on a front portion of the base 203 below the
frame 202. The jig base 204 is movably mounted on rails
16 205 mounted on the base 203 and extending in the direction
17 normal to the sheet of FIG. 22. Support members 207, 20
13 are vertically mounted on an upper member 20~ on the jig
19 base 104 and spaced apart from each other in the directionn
normal to the sheet of FIG. 22. The front support member
21 207 supports a pressure cylinder 209 having a rod 209a to
22 which there are coupled a member 210 for receiving the
23 upper portion l51a of the bumper face 151 and a lifter
24 cylinder 212 that supports a clamp cylinder 211 having a
rod 211a with a clamp finger 213 on its distal end.
26 Between the support members 207, 20~, there is disposed a
27 jig 214 for holding the body 151d of the bumper face 151.
1 31 ~066
1 A pressure cylinder (not shown) supported on the rear
2 support member 208 has a rod 215 projecting forwardly. The
3 rod 215 supports on its distal end a vertically movable
4 clamp finger 216 insertable in the air slits 151f of the
skirt 151e oE the bumper face 151.
6 The bumper face 151 can be se~ in place as shown
7 in FIGS. 25A through 25D. ~s shown in FIG. 25A, the bumper
8 face 151 is disposed on the jig 214 with the body 151d
9 positioned downwardly. The upper end of the upper portion
151a is put on the tip end of the receiving member 210.
11 Then, as shown in FIG. 25B, the clamp cylinder 211 is
12 driven to extend the rod 211a to move the clamp finger 213
13 Eorwardly. The lifter cylinder 212 is driven to move the
14 clamp cylinder 211 and the clamp flnger 213 downwardly to
the position of FIG. 25C. Then, the clamp cylinder 211 is
16 actuated to retract the clamp finger 213 to clamp the upper
17 end of the upper portion 151a against the tip end of the
18 receiving member 210 as illustrated in FIG. 25D. Although
19 not shown in FIGS. 25A through 25D, the clamp finger 216
(FIG. 23) is lifted when setting the bumper face 151 on the
21 jig 214 to engage in the air slits 151f of the skirt 151e.
22 As a result, the bumper face 151 is reliably set on the jig
23 214.
24 A support frame 217 is disposed behind and below
the frame 202, and a cross member 217b extends horizontally
26 between rear vertical frame members 217a of the support
27 frame 217. On the cross member 217b, there is vertically
:
- 32 -
.
, ~
1314066
1 supported a cylinder 218 by a bracket 219 for vertically
2 moving a heater 222 for heating the bumper face 151. The
3 cylinder 218 has a vertical rod 218a to which a support
4 base 220 is attached. A cylinder 221 for moving a bumper
face heater 222 back and forth is mounted on the support
6 base 220, the cylinder 221 having an axis extending in the
7 direction normal to the sheet of FIG. 22. The cylinder 221
8 has a rod 221a with its distal end supporting a holder 222a
9 of the heater 222. As shown in FIG. 22, the heater 222 has
a length which is substantially the same as that of the
11 bumper face 151 se-t below the heater 22~, and is shaped so
12 that it is loosely fitted in the space between thè upper
13 and lower portions 151a, 151c of the bumper face 151. The
14 heater 222 comprises two heater elements 222b spaced in the
direction normal to the sheet of FIG. 22. In FIG. 23, the
16 heater 222 is in an elevated position between the vertical
17 frame members 202a of the frame 202.
18 ~ cylinder 223 for moving a feed base for the
19 bumper beam 152 back and forth is mounted on a front
portion 217c of the rear support frame 217, the cylinder
21 223 having an axis extending in the direction normal to the
22 sheet of FIG. 22. The cylinder 223 has a rod 223a coupled
23 to a slider 226 slidable back and forth on rails 225 on the
24 front support Erame portion 217c. From the slider 226,
there extend forward}y two laterally spaced arms 227 having
26 front ends between which a laterally extending
27 channel-shaped feed base 228 for the bumper beam 152 is
'
~ - 33 -
, ' ' '' - ':
1 31 4066
1 attached, as shown in FIG. 22. The feed base 228 has a
2 horiæontal member 228a which is o~ substantially the same
3 length as that of the bumper beam 152, and vertical members
4 228b mounted on the opposite ends, respectively, of the
horizontal member 228a. The bumper beam 152 is set on the
6 feed base 228 by the worker such that its opposite ends are
7 qupported on the vertical members 228b and its intermediate
8 portion are supported on the horizontal member 228a.
9 A jig 229 (FIG. 22) for fixing the bumper beam
152 is disposed between the vertical frame members 202a of
11 the frame 202 and has laterally spaced holders 229a for
12 holding the bumber beam 152 at its laterally spaced
13 openings (not shown) defined in the upper member. The jig
14 229 has a vertically movable base 230 horizontally
supported between upper portions of the vertical frame
16 members 202a. Sprockets 23~ are rotatably mounted on lower
17 inner surfaces of the vertical frame members 202a. A drive
18 shaft 231 i~ rotatably supported on the frame 202 by
19 bearing bases 232, 233 and supports sprockets 235 on its
opposite ends. Chains 236 are trained around the
21 respective pairs of sproc~ets 234, 235 and have sides or
22 runs fi~ed to the iig base 230. One end 231a of the drive
23 shaft extends out beyond the bearing base 233, and two
24 sprockets 237 are mounted on the end 231a. A cylinder 238
for vertically moving the jiy 229 is vertically mounted by
26 a bracket 239 on the vertical frame member 202a over which
27 the sprockets 237 are positioned. The cylinder 238 has a
- 34 -
.,
1 3 1 4066
1 rod 238a having on its upper end an engagement member 240
2 coupled to chains 241 trained around the sprockets 237.
3 When the cylinder 238 is actuated, the rod 238a is
4 vertically moved to move the chains 241 thus rotating the
S sprockets 237 to rotate the drive shaft 231. Rotation of
6 the drive shaft 231 causes the chains 236 trained around
7 the sprockets 235, 234 to rotate to vertically move the jig
8 base 230 to which the chains 236 are affixed. As a result,
9 the jig 229 is also moved vertically. Denoted at 202c in
FIG. 22 are stoppers for limiting downward movement of the
11 base 230 by engaging the opposite ends of the jig base 230
12 on the vertical frame members 202a.
13 A heater 242 for heating the bumper beam 152 is
14 disposed below the intermediate portion of the horizontal
frame member 202b of the frame 202. The heater 242 has
16 symmetrical heater elements 242a, 242b spaced in the
17 direction normal to the sheet o~ FIG. 22. The heater
18 elements 242a, 242b are positioned so as to be aligned
19 respectively with the joining surfaces 153c, 154c and 153d,
154d of the bumper bea~ 152, and are supported on
21 respective front and rear symmetrical holders 243, 244
22 which are pivotally supported. ~s shown in FIG. 22, the
23 heater elements 242a, 242b are long in the lateral
24 direction of the apparatus and have a shape complementary
25 to the front and rear fusing surfaces 153c, 154c and 153d,
26 154d of the bumper beam 152. The holders 243, 244 are
27 plvotally supported on respective depending arms 243a, 244a
- 35 -
~ ~ .
1 31 4066
1 and coupled by links 247 to rods 245a of Eront and rear
2 cylinders 245, 246 spaced from each oth~r. The cylinders
3 245, 246 are suported on the horizontal frame member 202b
4 by means of brackets 248. Upon actuation of the cylinders
245, 246, the holders 243~ 244 are selectively closed and
6 opened to move the heater elements 242a, 242b toward and
7 away from each other, or close and open the heater 242. In
8 FIG. 23, the heater 242 is closed and the heater elements
9 242a, 242b are in a lowered position.
A process of fusing the bumper beam 152 to the
11 bumper face 151 using the fusing apparatus 200 will be
12 described below.
13 (I) First, the bumper face 151 is placed on the
14 jig 214 as shown in FIG. 23. As shown FIGS. 25A through
25D, the bumper face 151 is clamped by the clamp fingers
16 213, 216. The upper member 206 over the jig base 204 is
17 moved to the right in FIG. 23, i.e., in the rearward
18 direction of the apparatus, into a heating and melting
19 position. Then, the cylinder 221 is driven, and the heater
222 for heatlng the bumper face 151 is positioned above the
21 bumper face 151. Thereafter, the cylinder 218 is actuated
22 to lower the heater 222 with the support base 220 and the
23 cylinder 221 until the heater elements 222b are positioned
24 within the body 15Id of the bumper face 151, facing the
inner surfaces oE the upper and lower portions 151a, 151c
26 of the bumper face 151. In the same manner as the process
27 described with reference to FIGS. 8 through 13, the heater
- 36 -
1 3 1 ~066
1 elements 222b confronts the inner joining surfaces of the
2 body 151d in spaced relation. The heater elements 222b are
3 energized to heat and melt the inner joining surfaces of
4 the body 151d. At the same time, the cylinder 223 is
actuated to retract the feed base 228 with the bumper beam
6 152 placed thereon, and the heater elements 242a of the
7 heater 242 for heating the bumper beam 152 are elevated.
8 The bumper beam 152 is set below the heater elements 242a
9 of the heater 242, as shown in FIG. 26.
(II) Then, the jig 229 is lowered to grip the
11 bumper beam 152, and thereafter lifted to bring the joining
12 surfaces 153c, 154c and 153d, 15~d of the bumper beam 152
13 between the heater elements 242a, 242b. The heater
14 elements 242a, 2~2b are now disposed in facing but spaced
relation to the joining surfaces 153c, 154c and 153d, 154d
16 in the same manner as described with reference to FIGS. 8
17 through 13. These joining surfaces are then heated and
18 melted by the heater elements 2~2a, 242b.
19 ~III) Thereafter, the heater 222 i5 lifted and
then retracted out of the space above the bumper beam 152.
21 The feed base 228 is simultaneously moved back out of the
22 space below the bumper beam 152. Then, the jig 229 is
23 lo~ered to position the bumper beam 152 within the body
24 l51d of the bumper face 151, as shown in FIG. 27, where the
joining surfaces of the bumper beam 152 and the bumper face
26 151 are held against each other. The rod 209a of the
27 cylinder 209 and the rod 219 of the opposite cylinder (not
- 37 -
1 31 4066
1 shown) are moved toward each other to press the bumper beam
2 152 and the bumper Eace 151 together so that they are
3 firmly fused to each other into a bumper 150.
4 (IV) Subsequently, the jig 229 is released, and
the cylinder 209 and the opposite cylinder are also
6 released, followed by returning movement of the ]ig base
7 204 to its original position. The clamp finger 213 is then
8 released to discharge the bumper 150.
9 According to the apparatus 200, the FRP bumper
beam 152 and the bumper face 151 oE thermoplastic synthetic
11 resin are automatically heated and fused to produc~ the
12 resin bumper 150 in the successive process steps (I)
13 through (IV). Therefore, the operation efficiency is
14 increased, the manual labor is saved, the cost is lowered,
and bumpers can be mass-produced. The fusing apparatus 200
1~ can produce bumpers of various different shapes by
17 replacing the jigs 229, ~14 and the heaters 242, 222 with
18 other jigs and heaters.
19 Although there have been described what are at
present considered to be the preferred embodiments of the
2l present invention, it will be understood that the inven-tion
22 may be embodied in other specific forms without departing
23 from the spirit or essential characteristics thereof. The
24 present embodiments are therefore to be considered in all
aspects as illustrative, and not restrictive. The scope of
26 the invention is indicated by the appended claims rather
27 than by the foregoing description.
- 38 -
