Bus construction

Abstract

A method for constructing a bus, wherein a module associated with the front end of the bus is separately constructed and assembled to the shell after interior components of the bus have been installed. The shell of the bus can be fabricated at a first work station. The shell can be made transversely or laterally with respect to the longitudinal access of the bus to one or more work stations. At the subsequent work stations, interior components of the bus can be moved through the open ends of the bus. After the majority of the interior components have been installed with respect to the bus, the module supporting the windshield and bumper can be installed with respect to the shell. The module can also support the dashboard and steering column.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No. 10/350,466 for a Bus Construction, filed Jan. 24, 2003, which claims the benefit of U.S. Provisional Application No. 60/352,702 for a Bus Construction, filed Jan. 28, 2002, both of which are hereby incorporated herein by reference.

FIELD OF THE INVENTION

This invention relates to a method of manufacturing a motor vehicle bus and to the bus structure resulting from the invention methodology.

BACKGROUND OF THE INVENTION

Buses are typically manufactured by forming a closed shell structure including a roof, a structural floor, sides, front-end, and rear-end, moving the closed shell structure along a path aligned with the longitudinal axis of the structure, and loading components of the bus into the shell structure through the windows, doors, or windshield opening. The components may include, for example, the seats and the passenger compartment floor. This method is time consuming and labor intensive since it involves loading individual components into the bus individually and through relatively small apertures in the shell structure.

SUMMARY OF THE INVENTION

According to the invention, the shell structure is formed with an open front-end; the shell structure is moved laterally from station to station in a direction generally normal to the lengthwise axis of the shell structure; the interior components of the bus are loaded into the interior of the shell structure through the open front-end; a front-end module is attached to the front of the shell structure to close the front-end of the bus shell; the wheel assemblies are installed; and the shell structure is moved on its wheels along its lengthwise axis to various stations where the windows, doors, windshield, and exterior cladding are applied from locations generally outside of the shell structure.

Other applications of the present invention will become apparent to those skilled in the art when the following description of the best mode contemplated for practicing the invention is read in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The description herein makes reference to the accompanying drawings wherein like reference numerals refer to like parts throughout the several views, and wherein:

FIG. 1 is a perspective exploded view of a bus shell structure according to the invention;

FIG. 2 is a perspective exploded view of an alternate shell structure;

FIG. 3 is a layout view of an assembly plant for forming the bus structure;

FIG. 4 is a perspective view illustrating the loading of the seats into the shell structure; and

FIG. 5 is a perspective schematic view illustrating the loading of the passenger floor into the shell structure.

DESCRIPTION OF THE PREFERRED EMBODIMENT

As seen in FIG. 4, the plant 10 for assembling the bus structure includes assembly stations 1-7 and pre-assembly stations 8-17.

The basic bus shell structure 20 is formed in known manner at station 1 utilizing known assembly techniques and known jigs. Specifically, shell structure 20 includes lattice members 20a forming the sides of the shell, lattice members 20b forming the roof of the shell, and lattice members 20c forming the structural floor of the shell. Note that the front and rear ends 20e and 20d of the shell structure are open. The front-end of the shell structure, rather than being formed initially at station 1 as a fixed part of the shell structure, is formed as a separate module structure 22 in the pre-assembly area 15. Following formation of the shell structure 20 at station 1, minus the front module 22, the shell structure is moved in a direction lateral to the lengthwise axis of the shell structure, utilizing suitable dollies, to station 2 where the passenger floor of the bus is installed in overlying relation to the structural floor 20c.

As best seen in FIG. 4, the passenger floor or over-floor 24 may be prepared in two sections 24a and 24b at pre-assembly station 8 whereafter both sections are moved from pre-assembly station 8 through the open front-end 20e of the shell structure for installation in the shell structure. Floor structure 24a will be understood to be installed over the usual kick-up overlying the rear axle of the vehicle and floor section 24b will be understood to be installed forwardly of section 24a to cover the primary floor area of the shell structure. Floor sections 24a, 24b may be secured to the shell structure 20 using suitable glues for example. Floor sections 24a, 24b may be initially installed in the shell structure in an upperwardly tilted position, as seen in dash lines FIG. 4, whereafter they may be pivoted downwardly to their flat installed positions.

Following the floor installation at station 2 the shell structure 20 is moved laterally on the dollies to assembly station 3 where the engine assembly 26, prepared in pre-assembly station 9, may be installed through open rear end 20d of the shell structure and the seats 28, prepared at pre-assembly station 10, may be installed through the open front-end 20e of the shell structure. With reference to FIG. 5, the seats may be installed utilizing a forklift 30 positioned at pre-assembly station 10 and equipped with a boom 32 extending forwardly from the mast of the lift truck and including a plurality of pins 34 each hangably supporting a bus seat 28. With this arrangement the forklift may be maneuvered to insert the boom 32 carrying the seats 28 into the interior of the shell structure 20 through the open front-end 20e of the shell structure to position the seats proximate their ultimate locations in the bus, whereafter it is a simple matter to remove the seats 28 from the respective pins 34 and install the seats in the bus, thereby minimizing the amount of movement required to install each seat and specifically avoiding the awkward problem of moving each seat into the interior of the bus through a narrow window or side door opening and thereafter moving the seat lengthwise in the bus to its proper location. The seats are installed in the bus employing the usual bolting techniques.

Following installation of the engine assembly and the seats, the shell structure is moved laterally on the dollies to assembly station 4 where further interior and engine components are installed with the engine components being prepared at pre-assembly station 11 and installed through the open rear 20d of the shell structure and the interior components being prepared at pre-assembly station 12 and installed through the open front-end 20e of the shell structure.

The shell structure is thereafter moved laterally on the dollies to assembly station 5 where further interior components may be installed through the open front-end 20e of the shell structure from pre-assembly station 13 and a heating and air conditioning unit 36 (HVAC), prepared at pre-assembly station 14, may be installed through the rear 20d of the shell structure in overlying relation to engine assembly 26.

The shell structure is thereafter moved laterally on the dollies to assembly station 6 where the front-end module 22, which has been formed at pre-assembly station 15, is suitably attached to the front-end 20d of the shell structure utilizing, for example, bolts whereby to close the open front-end 20e of the shell structure. Module 22 may include instrument panel 38, windshield 40, steering column assembly 42, headlamp assemblies 44, front bumper 46, as well as suitable brake, throttle, and shift controls. Alternatively, as seen in FIG. 2, the front module may include only the windshield and front fascia and bumper of the bus with the instrument panel, steering column assembly, and vehicle controls being formed as a part of the main body shell structure 20. Following attachment of the module 22 at station 6, the shell structure is suitably elevated, the dollies are removed, and front and rear axle/wheel assemblies 48, 50, prepared at pre-assembly station 16, are slid under and suitably attached to the shell structure so that the shell structure is now supported for rolling movement on its wheels.

The bus is now rolled on its wheels in a direction parallel to the lengthwise axis of the shell structure to assembly station 7 where the bus windows 52, doors 54, 56 and side cladding 58 maybe installed from the pre-assembly station 17 wherein the installation takes place primarily from labor performed outside the opposite sides of the shell structure.

From station 7 the bus may be moved longitudinally on its wheels to further stations (not shown) where further exterior componentry may be suitably added whereafter the bus may be moved to suitable test and inspection stations.

The described bus structure and manufacturing methodology has several advantages as compared to prior art structures and methodologies. To wit:

• • the use of a modular front-end that is not attached to the main body shell structure until a later point in the assembly process allows all of the major interior components of the bus to be installed through the open front-end of the bus, rather than through narrow openings provided by the side doors and side windows of the shell structure where the front-end is fixedly secured to the main body shell structure prior to the installation of the interior components;
  • the late phase attachment of the front-end module allows an L-shaped assembly process wherein the bus is moved initially laterally through several stations in a direction normal to the lengthwise axis of the bus whereafter, following attachment of the front-end module and installation of the axle/wheel assemblies, the bus is moved in a direction parallel to the lengthwise axis of the bus. This L-shaped assembly format allows the provision of pre-assembly areas in the area defined between the legs of the L and in the areas along the outer faces of the legs whereby to provide a compact factory floor package plan with a substantial savings in floor space;
  • the use of the modular front-end allows the front-end to be removed in the event of a front-end accident and replaced immediately with a new replacement front-end so that the bus is out of service only for the time required to install the new front-end rather than for the much longer time required to repair the front-end;
  • the use of pre-assembly areas in parallel relation to the main assembly line to fabricate all of the primary sub-assemblies of the vehicle minimizes the number of workers working on the bus as it moves along the main assembly line, whereby to simplify the assembly procedures along the main assembly line;
  • the use of multiple pre-assembly areas allows specialists in each sub-assembly operation to be stationed at the respective sub-assembly areas, whereby to assure accurate, precise pre-assembly of the various sub-assembly components; and
  • the ability to install the floor through the open front-end of the shell structure in two large sections is vastly preferable to the prior art assembly procedure whereby, because of the closed front-end, the floor is moved into the interior of the bus in small sections which are thereafter pieced together and built up utilizing sanding and bondo operations to form the final composite floor structure.

While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiments but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the description, which scope is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures as is permitted under the law.

Claims

1. In a motor vehicle assembly line for assembling a mass transportation motor vehicle body, the mass transportation motor vehicle body comprising:

an elongate vehicle body lattice structure for supporting separately assembled roof, floor, and side body panels, the vehicle body lattice structure including a plurality of seats, floor panels, and having an open longitudinal end; and

a separate unitary front-end panel having a plurality of pre-installed members for enclosing the open longitudinal end of the vehicle body lattice structure, the pre-installed members including an outer fascia.

2. The motor vehicle body of claim 1, wherein the pre-installed members further include a bumper.

3. The motor vehicle body of claim 1, wherein the pre-installed members further include a steering column assembly.

4. The motor vehicle body of claim 1, wherein the pre-installed members further include at least one headlamp assembly.

5. The motor vehicle body of claim 1, wherein the pre-installed members further include an instrument panel.

6. The motor vehicle body of claim 1, wherein the pre-installed members further include a windshield.

7. The motor vehicle body of claim 1, wherein the pre-installed members further include at least one of a member for actuating a braking mechanism, a member for controlling an engine throttle, and a member for initiating shifting of a transmission.

8. A mass transportation motor vehicle body comprising:

an elongate vehicle body lattice structure for supporting separately assembled roof, floor, and side body panels, the vehicle body lattice structure having an open longitudinal end; and

a unitary front-end module removably connected to the lattice structure for enclosing the open longitudinal end of the lattice structure, the unitary front-end module being entirely detachable from the body lattice structure as a single unit, the front-end module including a front fascia and windshield.

9. The motor vehicle body of claim 8, wherein the front-end module further includes a bumper.

10. The motor vehicle body of claim 8, wherein the front-end module further includes a steering column assembly.

11. The motor vehicle body of claim 8, wherein the front-end module further includes a headlamp assembly.

12. The motor vehicle body of claim 8, wherein the front end module further includes an instrument panel.

13. The motor vehicle body of claim 8, wherein the front-end module further includes at least one of a member for actuating a braking mechanism, a member for controlling an engine throttle mechanism, and a member for initiating shifting of a transmission.

14. A roof support structure for a mass transportation motor vehicle body, the roof structure comprising:

an elongate first side rail having a forward end and an aft end;

an elongate second side rail having a forward end and an aft end, the second side rail displaced away from and aligned substantially parallel to the fist side rail;

a first elongate cross-member having a first end attached to the first side rail and a second end attached to the second side rail;

a second elongate cross-member having a first end attached the first side rail and a second end attached to the second side rail, wherein the first end of the first cross-member is attached to the first side rail forward of the first end of the second cross-member, and the second end of the second cross-member is attached to the second side rail forward of the second end of the second cross-member.

15. The roof support structure of claim 14, wherein the first cross-member is attached the second cross-member.

16. The roof support structure of claim 14, wherein the first cross-member includes a first beam and a second beam, an end of the first beam being positioned adjacent an end of the second beam, each of the first and second beams having an end attached to the second cross-member.

17. The roof support structure of claim 14 further comprising a reinforcing member attached to the first and second cross-members and detached, the reinforcing member being detached from the first and second side rails.

18. The roof support structure of claim 14, wherein each of the first and second cross-members includes a first beam and a second beam, an end of the first beam of the first cross-member being attached to an end of the second beam of the second cross-member and an end of the second beam of the first cross-member being attached to an end of the first beam of the second cross-member.

19. The roof support structure of claim 18, wherein the end of the first beam of the first cross-member is attached to the end of the first beam of the second cross-member.

20. The roof support structure of claim 18 further comprising a reinforcing member attached to the first and second beams of the first cross-member and the first and second beams of the second cross-member.