Production of vehicles

This is a Divisional of application Ser. No. 09/458,692, filed Dec. 10, 1999.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to production of vehicles, and more particularly to a production method of vehicles, a production system of vehicles, and a vehicle.

2. Acronyms

The written description provided herein contains acronyms, which refer, for example, to various stages of production of vehicles. For purposes of the written description herein, acronyms will be defined as follows:

Floor Process Unit (FPU)

Interior Parts Mount Process Unit (IPMPU)

Body Main Process Unit (BMPU)

Running Parts Mount Process Unit (RPMPU)

Exterior Parts Attachment Process Unit (EPAPU)

Assembly Process Unit (APU)

Weld Process Unit (WPU)

Floor Main Process Unit (FMPU)

Rear Floor Module Process Unit (RFMPU)

Rear End Module Process Unit (REMPU)

Body Side LH Process Unit (BSLHPU)

Roof Process Unit (RPU)

Body Side RH Process Unit (BSRHPU)

Body Side Sub-line Inner Trimming Unit (BSSITU)

Set Process Unit (SPU)

Body Unit (UBU)

Under Running Unit (URU)

Liquid Supply Process Unit (LSPU)

Window Attachment Process Unit (WAPU)

Door Mount Process Unit (DMPU)

Exterior Surface Decoration Process Unit (ESDPU)

Right-hand Door Assembly Process Unit (RDAPU)

Left-hand Door Assembly Process Unit (LDAPU)

3. Background Information

In production of a body of an automotive vehicle, a various kinds of pillars, side sills, side members, cross members, a cowl box, and roof rails are made of a structurally strengthened member having a closed section, and they are connected to form a body structure. Body panels are attached to the structure to form a three-dimensional appearance of the body.

SUMMARY OF THE INVENTION

Within a plant, an automated production line is installed for production of automotive vehicles. The production line begins with a pressing process for production of body panels of different three-dimensional appearances. Conventionally, a painting and coating process is included in the production line. The painting process necessarily requires a drying process. Also included in the production line is equipment to cope with a change in body color. The drying process requires a lot of space within the plant. Accordingly, the conventional production of vehicles requires a great number of processes ranging from 800 to 1000 if a space needed for one vehicle is counted as one process.

The conventional production of vehicles demands workers to do their jobs within such closed spaces as an engine compartment and a vehicle cabin. Thus, much time and effort are consumed. For example, a worker must enter a vehicle cabin through an opening for a door to do his job.

An object of the present invention is to accomplish an enormous reduction in number of processes for production of vehicles as well as a remarkable improvement in working environment.

According to one aspect of the present invention, there is provided a method of production of vehicles, comprising:

a floor process of assembling floor constituent parts, each being a light metal extrusion die cast product, and connecting said assembled floor constituent parts to make a floor structure;

an interior parts mount process of mounting interior parts to said floor structure to make a floor unit;

a body main process of trimming each of two body side structures to make a body side unit, trimming a roof structure to make a roof unit, assembling said floor unit, said body side units, and said roof structure, and connecting said assembled floor unit, body side units and roof unit to make a body unit;

a running parts mount process of mounting to said body unit an under running unit that includes an engine, a power train, and a suspension unit; and

an exterior parts attachment process of attaching body panels to said body unit.

According to another aspect of the present invention, there is provided a system of production of vehicles, comprising:

a floor process unit (FPU) for assembling floor constituent parts, each being a light metal extrusion die cast product, and connecting said assembled floor constituent parts to make a floor structure;

an interior parts mount process unit (IPMPU) for mounting interior parts to said floor structure to make a floor unit;

a body main process unit (BMPU) for trimming each of two body side structures to make a body side unit, trimming a roof structure to make a roof unit, assembling said floor unit, said body side units, and said roof structure, and connecting said assembled floor unit, body side units and roof unit to make a body unit;

a running parts mount process unit (RPMPU) for mounting to said body unit an under running unit that includes an engine, a power train, and a suspension unit; and

an exterior parts attachment process unit (EPAPU) for attaching body panels to said body unit.

According to other aspect of the present invention, there is provided an automotive vehicle comprising:

a floor unit made by mounting parts to a floor structure that has been made by assembling and connecting floor constituent parts, each being a light metal extrusion die cast product;

two body side units made by trimming two body side structures;

a roof unit made by trimming a roof structure;

said roof unit, said body side units, and said roof unit being assembled and connected to make a body unit;

an under running unit that includes an engine, a power train, and a suspension unit, said under running unit being mounted to said body unit;

door units made by trimming door structures, said door units being mounted to said body unit; and

body panels attached at least to said body unit.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B

, when combined, illustrate a diagrammatic plan view of an assembly shop for automotive vehicles implementing the present invention.

FIGS. 2A through 2H

illustrate how parts are combined in various production stages on an assembly line to make a vehicle.

FIG. 3

is a perspective view of an assembly process unit of a floor process unit.

FIG. 4A

is an exploded perspective view of a front floor section illustrating a front, an intermediate, and a rear constituent part.

FIG. 4B

is a cross section taken through the line

4

—

4

of FIG.

4

A.

FIGS. 5A

,

5

B, and

5

C illustrate process steps of coupling between the front and intermediate floor constituent parts.

FIG. 6

is an exploded perspective view of an engine compartment frame.

FIG. 7A

is a perspective view of a rear floor frame.

FIG. 7B

is an exploded perspective view of a portion of the rear frame.

FIGS. 8A

,

8

B, and

8

C are exploded perspective views of floor structures for three different vehicle body types.

FIG. 9

is a perspective view of a portion of a vehicle production line, illustrating a weld process unit for welding constituent parts to make a floor structure.

FIG. 10

is the same view as

FIG. 5C

, illustrating a welding portion.

FIG. 11

is a perspective view of a rear floor module process unit where a rear floor module is made.

FIG. 12

is a perspective view of a rear end module process unit where a rear end module is made.

FIG. 13

is a perspective exploded view of a floor unit, illustrating how interior parts, such as a dash module, seats, a rear floor module, and a rear end module, are mounted to a floor structure.

FIG. 14

is a perspective view of a body main process unit where the floor unit, body side units and a roof unit are assembled to make an upper main body unit.

FIG. 15

is a perspective view of a portion of the body main process unit, illustrating a portion of a roof process unit that includes a set process unit.

FIG. 16

is a greatly simplified exploded view, illustrating where a floor unit, a body side unit, and a roof unit are positioned relative to each other as well as structures for positioning.

FIG. 17

is a fragmentary enlarged section taken through the line

17

—

17

of

FIG. 16

before engagement with the roof unit, illustrating the left-hand body side unit provisionally connected to the floor unit with a pin into a locate hole.

FIG. 18A

is a diagrammatic section taken through the line

17

—

17

of

FIG. 16

before engagement with the roof unit.

FIG. 18B

is a diagrammatic section taken through the line

17

—

17

of

FIG. 16

after engagement with the roof unit.

FIG. 19

is a fragmentary section showing a rear pillar structure around a pin inserted into a locate hole.

FIG. 20

is a perspective view illustrating an under running unit mount process unit where a body unit and an under running unit are joined.

FIG. 21

is a perspective fragmentary view of a right-hand door assembly process unit.

FIG. 22

is a fragmentary exploded view illustrating where to attach resin panels.

FIG. 23

is a fragmentary section illustrating a structure by which a roof resin panel is mounted in a roof opening.

FIG. 24

is a fragmentary section illustrating a structure by which a front fender resin panel is attached to a hood ridge.

FIG. 25

is a fragmentary section illustrating a structure by which a rear fender resin panel is attached to a wheel housing opening defining edge.

FIG. 26

is an exploded perspective view of a portion of anther example of a floor structure with joints and a dash cross member.

FIG. 27

is an exploded perspective view of a portion of the floor structure shown in FIG.

26

.

FIG. 28

is a fragmentary section taken through the line

28

—

28

in FIG.

27

.

FIG. 29

is a fragmentary perspective view of the floor structure with joints shown in FIG.

26

.

FIG. 30

is a simplified diagrammatic view illustrating a joint prior to insertion into a bore that extends inwardly from one end of a front floor center.

FIG. 31

is a view similar to

FIG. 30

illustrating the joint inserted into the bore of the front floor center.

FIG. 32

is a section taken through the line

32

—

32

of

FIG. 31

with the joint being prior to insertion into the bore of the front floor center.

FIG. 33

is a section taken through the line

32

—

32

of

FIG. 31

with a dash cross member coupled with the joint.

FIG. 34

is a perspective view, illustrating an engine compartment frame.

FIG. 35

is an exploded view of side members of the engine compartment frame in FIG.

34

.

FIG. 36

is a perspective exploded view of a front floor structure, a dash cross member and an engine compartment frame incorporating another example of coupling structure between the dash cross member and the front floor structure.

FIG. 37

is a fragmentary side view of a lower portion the dash cross member shown in

FIG. 36

together with a section taken though the line

37

—

37

of the front floor structure, illustrating a female coupling section on the dash cross member and a male coupling section on the front floor structure.

FIG. 38

is a similar section to

FIG. 37

illustrating a reinforcement fixedly attached to the dash cross member and a support which the dash cross member is placed on during assembly with the front floor structure.

FIG. 39

is a fragmentary perspective view of the dash cross member with the reinforcement, illustrating locations of an integral boss and an integral rib of the reinforcement for positioning the front floor structure.

FIG. 40

is a section taken through the line

40

—

40

of

FIG. 39

, illustrating the integral boss of the reinforcement.

FIG. 41

is a view viewing

FIG. 39

along an arrow

41

, illustrating the integral rib of the reinforcement.

FIG. 42

is a similar view to

FIG. 37

, illustrating still another example of female and male coupling sections.

FIG. 43

is a similar view to

FIG. 37

, illustrating female and male coupling sections fixedly connected by bolt and nut connections.

FIG. 44

is a similar view to

FIG. 43

, illustrating female and male coupling sections fixedly connected by adhesive.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to the accompanying drawings, like reference and numerals are used throughout all Figures to designate like or similar parts or portions.

FIGS. 1A and 1B

, when combined, illustrate a diagrammatic plan view of an assembly shop for automotive vehicles implementing the present invention. In

FIGS. 1A and 1B

, the reference numeral A generally indicates a floor process unit (FPU). An interior parts mount process unit (IPMPU) B follows the FPU A. A body main process unit (BMPU) C follows the IPMPU B. A running parts mount process unit (RPMPU) D follows the BMPU C. An exterior parts attachment process unit (EPAPU) F follows the RPMPU D.

The FPU A, which will be further described later in connection with

FIGS. 3 and 9

, performs a process of producing a floor. Floor constituent parts are light metal die cast parts, respectively. In various examples of the present application, an aluminum alloy is used in a standard casting process although a magnesium base alloy may be used as well. Workers assemble the floor constituent parts and a welding machine is used to securely connect them to produce a floor structure. The FPU A includes an assembly process unit (APU)

1

and a weld process unit (WPU)

3

. The APU

1

includes a floor main process unit (FMPU)

5

and two sub-process units

7

and

9

. Workers engage in jobs supporting each of the FMPU

5

and the sub-process units

7

and

9

.

The IPMPU B, which will be further described later in connection with

FIGS. 11 and 12

, includes a rear floor module process unit (RFMPU)

11

and a rear end module process unit (REMPU)

13

. Workers support each of the RFMPU

11

and REMPU

13

. The IPMPU B also includes two manual lifts

4

in the neighborhood of the RFMPU

11

and REMPU

13

, respectively, to assist worker(s) in transferring products to a main line. It further includes a dash module pallet

15

, an engine room parts pallet

17

, a carpet pallet

19

, a rear sheet pallet

21

, a console pallet

23

, and a front sheet pallet

25

. These pallets carry the parts. To assist worker(s) in transferring the parts to the main line, four manual lifts

4

are provided.

The BMPU C, which will be further described later in connection with

FIGS. 14 and 15

, includes a body side LH process unit (BSLHPU)

27

, a roof process unit (RPU)

29

, and a body side RH process unit (BSRHPU)

31

. The BSLHPU

27

functions to produce a body side unit by trimming the interior of a body side structure. The BSLHPU

27

includes a body side sub-line inner trimming unit (BSSITU)

33

, a body side set dolly

35

, and a set of body side pallets

37

. The body side pallets

37

and other pallets carry necessary parts for production of body side units. Workers support the BSSITU

33

. The BSRHPU

31

functions to produce a body side unit by trimming the interior of a body side structure. The BSRHPU

31

includes a body side sub-line inner trimming unit (BSSITU)

39

, a body side set dolly

41

, and a set of body side pallets

43

. The body side pallets

43

and other pallets carry necessary parts for production of body side units. Workers support the BSSITU

39

. The RPU

29

includes a set process unit (SPU)

45

, and a roof-reversing arm

47

. Roof parts needed for different automobile types are carried by a plurality of pallets, namely, a small-sized (S-sized) sedan pallet

49

, a small-sized (S-sized) tall pallet

51

, a wagon pallet

53

, a SS-sized commuter pallet

55

, and a medium-sized (M-sized) sedan pallet

57

.

The BMPU C further includes a weld process unit (WPU)

58

where the assembled roof unit, body side units, and roof unit are fixedly secured by laser welding.

Parts needed for trimming roofs having different widths and body sides are stored in pallets and located in a parts stock site

103

. Theses pallets are supplied to sub-lines according to production order.

The RPMPU D, which will be further described later in connection with

FIG. 20

, includes an automatic mounting machine

59

for mounting a body unit (UBU) to an under running unit (URU)

60

having been supplied to the line.

The EPAPU F follows the RPMPU D. The EPAPU F is followed by a liquid supply process unit (LSPU) G, a window attachment process unit (WAPU) H, a door mount process unit (DMPU) I, and an exterior surface decoration process unit (ESDPU) E.

The EPAPU F includes a rear bumper pallet

63

, a front bumper pallet

65

, a front end module pallet

67

, and a lift

4

adjacent the front end module pallet

67

to assist a worker in conveying a front end module to the line. Workers draw a rear bumper from the pallet

63

and attach it to the rear end of the body unit. They draw a front bumper from the pallet

65

and attach it to the front end of the body unit. Using the lift

4

, the workers mount a front end module to the body unit.

The LSPU G includes a long life coolant supply station

68

, a gasoline supply station

69

, a brake oil supply station

71

and a power steering oil supply station

73

. Necessary parts are provided at

72

. A worker supply the vehicle with long life coolant, gasoline, brake oil and power steering oil.

The WAPU H includes a lamp pallet

74

and a windshield panel pallet

75

. Workers mount windshields to the body unit after drawing parts out of these pallets

74

and

75

.

The DMPU I, which will be described later in connection with

FIG. 21

, includes a right-hand door assembly process unit (RDAPU)

77

, and a left-hand door assembly process unit (LDAPU)

78

. Lifts

4

are provided adjacent to the RDAPU

77

and LDAPU

78

, respectively. Workers support the RDAPU

77

and LDAPU

78

. Using the lifts

4

, workers can mount the door units out of the RDAPU

77

and LDAPU

78

to the body unit.

Referring also to

FIG. 21

, the RDAPU

77

includes a sash module front pallet

79

, a door mirror unit pallet

83

, an interior trim module pallet

85

, and an inner module pallet

87

around a roller conveyer

467

to make it easier for workers to assemble parts. The LDAPU

78

is substantially the same in construction as the RDAPU

77

so that the same reference numerals are used to designate like portions. Lifts

4

are provided adjacent the RDAPU

77

and LDAPU

78

, respectively.

Finally, the ESDPU E includes a roof pallet

89

for carrying a roof decoration plate of synthetic resin, a rear fender pallet

91

for carrying a rear fender decoration plate of synthetic resin, a front fender pallet

93

for carrying a front fender decoration plate of synthetic resin, a trunk lid pallet

95

for carrying a trunk lid decoration plate of synthetic resin, and a hood pallet

97

for carrying a hood decoration plate of synthetic resin. Workers draw the necessary decoration plates out of the pallets

89

,

91

,

93

,

95

, and

97

and attach them to the body unit.

Parts needed by the above-mentioned process units A, B, C, D, F, G, H, I, and E are stocked at the adjacent sites

99

,

101

,

103

,

105

,

107

,

109

, and

111

.

First of all, a die casting process is used to make a light metal die cast part, which serves as one of floor constituent parts. In the die casting process, molten light metal, such as aluminum (Al) alloy and magnesium (Mg) alloy, is forced into a die. In this example, the floor constituent parts are made of aluminum alloy extrusion die cast products. In the FPU A, workers manually engage in assembling the floor constituent parts. In the WPU

3

, a welding machine welds the assembled floor constituent parts to produce a floor structure. Subsequently, in the IPMPU B, the rear floor module, rear end module, dash module, engine room parts, carpet, rear sheet, console, and front sheet are mounted onto the floor structure to produce a floor unit (FU). The floor unit is conveyed to the BMPU C.

In the BMPU C, the BSSITU

33

produces a left-hand body side unit that has been trimmed, and the BSSITU

39

produces a right-hand body side unit that has been trimmed. The body side set dolly

35

is used to transfer the left-hand body side unit to the left-hand side of the floor structure for attachment thereto. The body side set dolly

41

is used to transfer the right-hand body side unit to the right-hand side of the floor structure for attachment thereto. Subsequently, the roof-reversing arm

47

sets a roof unit for attachment to the upper ends of the body side units. In the SPU

45

, a selected roof structure fit for type of vehicle is trimmed to produce a roof unit, and the roof unit is supplied to the roof-reversing arm

47

.

After assembling the floor unit, body side units, and roof unit, they are fixedly secured to each other by laser welding in the WPU

58

to fixedly interconnect body parts of a body unit (UBU).

In the RPMPU D, the automatic mounting machine

59

is used to mount an under running unit (URU)

60

to the body unit to produce a vehicle core. The under running unit

60

includes an engine, a power train, and a suspension. In the EPAPU F, a rear bumper, a front bumper, a front end module, and etc. are attached to the vehicle core. In the LSPU G, long life coolant, gasoline, brake oil, and power steering oil are fed to the vehicle core.

In the WAPU H, windshield panels are mounted to the vehicle core. In DMPU I, left-hand and right-hand door units are mounted to the vehicle core. Each of the door units has attached thereto a sash module front, a door mirror, an interior trim module, and an inner module.

Finally, in the ESDPU E, a roof decoration plate of synthetic resin, a rear fender decoration plate of synthetic resin, a front fender decoration plate of synthetic resin, a trunk lid decoration plate of synthetic resin, and a hood decoration plate of synthetic resin are attached to the vehicle core. An inspection line follows the EPDPU E.

From the preceding description, it is now understood that workers can mount seats, an instrument panel, harness, and the other necessary equipments to the floor structure in an open space. It is also understood that workers can conduct trimming of the body sides and the roof in an open space. Thus, workers load in assembly of the vehicle body is greatly reduced.

A painting process is no longer required. Thus, there is no need to alter painting equipment to cope with color switching. Assembling bodies can synchronize with assembling of vehicles. Stocks of bodies and parts associated therewith are greatly reduced, in number.

A very compactor short vehicle assembly line is accomplished. This is because line length from the initiation of assembly of bodies to the completion of vehicles has been reduced to sixteen (16) processes from the conventional line length of about eight hundred (800) processes.

Accordingly, the time required from the initiation of assembly of a body to the completion of a vehicle is greatly shortened. This makes it possible to shorten the time required from order to deliver. Conventional stock production can be replaced with order production. If order production is employed, stocks are greatly reduced, in number, thus resulting in a reduction in cost needed for transportation and stock control. Because the assembly line length for vehicle production can be greatly shortened, only a small area suffices for establishment of an assembly shop.

Referring to

FIGS. 2A through 2H

, it is illustrated how parts are combined in various production stages on the assembly line to make a vehicle.

FIG. 2A

illustrates a floor structure

113

on the assembly line immediately downstream of the FPU A.

FIG. 2B

illustrates the floor structure

113

with a rear floor module

115

and a rear end module

117

on the assembly line immediately downstream of the RFMPU

11

and REMPU

13

of the IPMPU B.

FIG. 2C

illustrates the floor structure

113

with a dash module

118

, front sheets

119

and

121

, and a rear sheet

123

on the assembly line immediately downstream of the IPMPU B to make a floor unit (FU).

FIG. 2D

illustrates the FU with body side units (BSU) on the assembly line immediately downstream of the BSLHPU

27

and BSRHP

31

of the BMPU C.

FIG. 2E

illustrates the FU with a roof unit (RU) on the BSUs on the assembly line immediately of the RPI

29

of the BMPU C. Laser welding in the WPU

58

fixedly secures the FU, BSUs and RU to each other to make a body unit (UBU).

FIG. 2F

illustrates the UBU with an under running unit (URU)

60

on the assembly line immediately downstream of the RPMPU D. The URU

60

includes an engine

131

.

FIG. 2G

illustrates the USU with the URU

60

and also with door units

133

,

137

, windshield panels

149

,

141

, and liquid additives including engine brake oil, which is on the assembly line immediately downstream of DMPU I after the EPAPU F, LSPU G, and WAPU H.

FIG. 2H

illustrates a vehicle off the assembly line immediately downstream of the ESDPU E, which vehicle has attached thereto a roof panel of synthetic resin

143

, a rear fender panel of synthetic resin

145

, a front fender panel of synthetic resin

147

, a trunk lid panel of synthetic resin

149

, and a hood panel of synthetic resin

151

.

FIG. 3

is a perspective view of the FPU A with its WPU

3

removed. The floor main process unit

5

and the sub-process units

7

and

9

have manual roller conveyers

153

,

155

, and

157

, respectively. The floor main process unit

5

has three pallets

159

,

161

, and

163

. These pallets

159

,

161

, and

163

are placed on load responsive extendable wheeled supports

173

,

175

, and

177

, respectively. The sub-process unit

7

has one pallet

165

that is placed on a load responsive extendable wheeled support

179

. The other sub-process unit

9

has three pallets

167

,

169

, and

171

. These pallets

167

,

169

, and

171

are placed on load responsive extendable wheeled supports

181

,

183

, and

185

, respectively. Each of the supports

173

,

175

,

177

,

179

,

181

,

183

, and

185

extends as weight of the pallet placed thereon decreases.

Referring also to

FIGS. 1A and 1B

, the pellets

159

,

161

, and

163

are located near the site

101

, and the pallets

165

,

167

,

169

, and

171

are located near the site

99

. After loading the pallets

159

,

161

, and

163

with the corresponding parts from the site

101

, workers manually deliver them to locations as illustrated in

FIG. 3

near the roller conveyer

153

. Similarly, after loading the pallets

165

,

167

,

169

, and

171

with the corresponding parts from the site

99

, workers deliver them to locations as illustrated in FIG.

3

. For smooth supply of a pallet carrying a relatively heavy part to an area with the reach of hands of a worker attending the assembly work, a pallet shooter incorporating wheel conveyer is used.

Each of the pallets

159

,

161

, and

163

has a plurality of shelves. A plurality of rear front floor constituent parts

195

are put on each of the shelves of the pallet

159

. A plurality of middle front floor constituent parts

193

are put on each of the shelves of the pallet

161

. A plurality of front floor constituent parts

191

are put on each of the shelves of the pallet

163

. The pallet

165

has a plurality of shelves. A set of constituent parts of an engine compartment frame

187

is put on each of the shelves of the pallet

165

. Each of the pallets

167

,

169

, and

171

has a plurality of shelves. Constituent parts of a rear floor frame

189

are put on shelves of the pallets

167

,

169

, and

171

, respectively.

With regard to the pallets

159

,

161

,

163

,

165

,

167

,

169

, and

171

, removing a part from a shelf of one of them, for example the pallet

159

, causes a reduction in the magnitude of load imparted to the associated support

173

. This reduction causes the support

173

to extend to lift the next lower shelf to a level as high as the roller bearing

153

. This greatly assists the worker in manually drawing the part from the pallet to the surface of the roller bearing. When the pallets are empty, the workers move the extendable supports

173

,

175

,

177

,

179

,

181

,

183

, and

185

to the corresponding sites

101

and

99

and load the pallets with new parts.

The FPU A realizes a cellular production line. The sub-process units

7

and

9

extend from the floor main process unit

5

to accomplish the cellular production. This makes it possible to simultaneously assemble all the constituent parts needed to complete a floor structure, avoiding a need to stock incompletely assembled portions of a floor structure.

The sub-process unit

7

provides for manual assembly, on the roller conveyer

155

, of parts needed to make the engine compartment frame

187

. The sub-process unit

9

provides for manual assembly, on the roller conveyer

157

, of parts needed to make the rear floor frame

189

. The floor main process unit

5

provides for manual assembly, on the roller conveyer

153

, of the front floor constituent parts

191

,

193

, and

195

, the engine compartment frame

187

and rear floor frame

189

.

Each of the floor constituent parts is made of an aluminum alloy die cast part and low, in weight, enough for worker to handle. Thus, even women and/or aged people can engage in the assembly work.

FIG. 4A

illustrates the front, intermediate, and rear constituent parts

192

,

193

, and

195

of the front floor. Each of them is an aluminum alloy extrusion die cast product that has been made, in an extrusion die casting process, by forcing molten aluminum alloy through the mold cavity in a direction adapted to be parallel to a transverse direction of the vehicle. The front, intermediate, and rear constituent parts

192

,

193

, and

195

are formed with locate holes

197

,

199

, and

201

, respectively. The front and intermediate constituent part

191

and

193

are formed with grooves

205

and

207

adapted to receive seat attachment brackets

203

. The locate holes

197

,

199

, and

201

as well as the grooves

205

and

207

are formed in the die casting process.

At a front end, the front floor constituent part

191

is formed with a male coupling section

209

. At a rear end, it is formed with a female coupling section

211

. At a front end, the intermediate front floor constituent part

193

is formed with a male coupling section

213

. At a rear end, it is formed with a female coupling section

215

. At a front end, the rear front floor constituent part

195

is formed with a male coupling section

217

. At a rear end, it is formed with a female coupling section

219

.

With the male coupling section

213

engaged in the female coupling section

211

, the front floor constituent parts

193

and

191

are joined to each other. With the female coupling section

217

engaged in the male coupling section

215

, the front floor constituent parts

193

and

195

are joined to each other. The male and female coupling sections

213

,

211

, and the male and female coupling sections

215

,

217

employ substantially the same structure. Referring to

FIG. 4B

, and

FIGS. 5A

to

5

C, the structure of the male and female coupling sections

213

and

211

is further described.

As illustrated in

FIGS. 4B

, and

FIGS. 5A

to

5

C, the female coupling section

211

is formed with a positioning protrusion

223

on its bottom wall

221

. The male coupling section

213

is formed with a positioning recess

225

a

on its leading or one end wall

225

. Engagement of the protrusion

223

into the recess

225

a

prevents undesired rotation of the constituent part

193

in a direction to disengage from the constituent part

191

.

The female coupling section

211

has a groove that is defined by the bottom wall

221

and two spaced parallel flange inner walls

235

extending from the bottom wall

221

. The inboard or upper flange extends further than the outboard or lower flange does to prevent transmission of noises to the vehicle cabin. Clips

227

are disposed near leading ends of the inner walls of the upper and lower flanges to define a mouth of the groove. The clips

227

protrude inwardly from the upper and lower flanges, respectively. The male coupling section

213

is formed with clip receiving recesses

229

, which receive the clips

227

, respectively. The male coupling section

213

is provided with surface portions

231

, which come into close contact, over the whole area, with the flange inner walls

235

, respectively, when the male coupling section

193

engages in the groove of the female coupling section

211

. One of the surface portions

231

is located between the end wall

225

of the male coupling section

193

and one of the clip receiving recesses

229

. The other of the surface portions

231

is located between the end wall

225

of the male coupling section

193

and the other of the clip receiving recesses

229

.

Prior to coupling, a worker puts adhesive

233

in the clip receiving recess

229

of the male coupling section

193

near the vehicle cabin. As shown in

FIG. 5A

, the worker engages the end wall

225

of the male coupling section

213

with the inboard and outboard clips

227

of the female coupling section

211

. Then, the worker pushes the male coupling section

193

into the groove of the female coupling section

211

until the outboard clip

227

engages in the outboard recess

229

as shown in FIG.

5

B. Finally, the worker rotates the male coupling section

213

about the outboard clip

227

until the inboard clip

227

engages in the inboard recess

229

and the position protrusion

223

engages in the position recess

225

a

, thus completing the coupling as shown in FIG.

5

C.

In the illustrated position of

FIG. 5C

, the adhesive

233

provide a firm connection between the recess

229

of the male coupling section

213

and the inboard flange inner wall

235

of the female coupling section

211

, and the surface portions

231

of the male coupling section

213

firmly engage the flange inner walls

235

of the female coupling section

211

. The firm engagement with the flange inner walls

235

at the surface portions

231

and the adhesive

233

prevent passage of water and gas into the vehicle cabin.

Coupling between the constituent parts

193

and

195

can be accomplished by engaging the male coupling section

215

in the female coupling section

217

in the same manner.

FIG. 6

illustrates an engine compartment frame

187

, which serves as a constituent part of the floor. The engine compartment frame

187

is made of and dividable into four parts, namely, a dash lower cross member

237