Metal working – Method of mechanical manufacture – Converting
Reexamination Certificate
1997-08-25
2001-01-16
Hughes, S. Thomas (Department: 3726)
Metal working
Method of mechanical manufacture
Converting
C029S426200, C029S426100
Reexamination Certificate
active
06173482
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention sets forth a vehicle structure and provides a method for improving a military vehicle of the armored, tracked, troop carrying type to create a more cost-efficient, producible design with improved vertical obstacle crossing capability, and higher off-road cross country mobility.
2. Description of the Prior Art
Armored tracked vehicles of the troop carrying type, such as an “M113” armored personnel carrier, have been in production for over 35 years. This type of vehicle has been used for various services, including as a command post, missile launcher, hazardous material incidents respond vehicle, cargo carrier, ambulance, reconnaissance and recovery vehicle. The same chassis structure has been used for each of these vehicle types. The traditional design of this family of vehicles included two box beam extrusions, forming lateral perimeter frame members of the hull. These box beam extrusions extend from the front of the vehicle to the back of the vehicle. Integrated to the outboard surfaces of each of the box beam extrusions are lower side plates, personnel protection plates and the five roadwheel trunnion mounting pads or “bogey” pads used to accommodate the suspension of the vehicle.
In the current production model of this vehicle, the joining of the lower side plates and the personnel protection plates to form the lower hull is labor intensive and time consuming. First, the personnel protection plate, sometimes referred to as a doubler, had to be welded to the lower side plate. The resultant subassembly then had to be subjected to a straightening procedure to restraighten the lower side plate weld processing distortion. Afterwards, the subassembly, consisting of the lower side plate and the doubler, had to be welded to the box beams. Again, the lower side plate assembly had to be straightened due to the weld process distortion from welding the lower side plates to the box beams. At this point of fabrication of the lower hull, the last remaining significant element to be completed was the welding of the bogey pads to the exterior vehicle surface of the box beams. In some instances, even at this stage, the final lower side plate would need straightening due to the weld process distortion from welding the bogey pads to the lower side plate assembly.
U.S. Pat. No. 5,490,314,
Stretch Vehicle Conversion Method,
included modification procedure that resulted in an upper hull that was mostly discarded and recycled because of where the original upper hull had to be cut to accommodate the replacement stretched lower hull. In the instant invention, the upper hull is largely reused in the improved modified hull presented here. As a result, the intact equipment mounting provisions, that is, the myriad attachment points, fixtures and surface indentations do not have to be refabricated on a totally new hull as they are intact on the original hull. This results in tremendous time savings in the conversion process.
SUMMARY OF THE INVENTION
It is an object of the invention to provide an armored personnel carrier or infantry fighting vehicle modified from a prior existing donor vehicle at a reduced manufacturing cost without degradation of ballistic protection or hull structure rigidity.
Another object of the invention is to enhance resistance of the exposed surfaces of an infantry fighting vehicle to penetration of piercing fragments from land mine explosions by provision of a thicker lower side plate of the hull structure and the accommodation of an armor plate fastened to the bottom of the sponson portion of the lower hull structure.
The present invention is primarily concerned with a new hull structure for use “under” an existing superstructure for the family of tracked vehicles normally used for troop transportation. Particularly, the hull configuration and modification method disclosed herein includes replacing the current multi-element assembly in the lower hull with a single, thick metal plate. The new structure will have the structural rigidity of the prior art hull without the need for box beam frame members. This is accomplished by machining of the new metal plate rather than the creation of an assembly by welding the various elements together to form the lower hull side plate. As a result of the replacement of the box beam structure with the monocoque structure of the lower hull, the suspension components can be bolted closer to the bottom of the hull because the bogey pads can now protrude below the bottom plate surface without consideration for the necessary weld seam area around such an external pad. This results in measurably increased vehicle ground clearance, everything else being equal. Also, the new hull structure provides for additional space under the bottom side of the sponson to accommodate an armor plate. This was not possible in the previous structure without significantly reducing the suspension travel and impeding cross country mobility and agility. It is this armor plate and the thicker lower side plate that provide the increased resistance to the penetration of piercing fragments from mine explosion advantage mentioned above.
A second advantageous element of the single thick vertical metal plate construction, the monocoque lower hull mentioned above, is the producibility gains by eliminating the need for two sub-assembly weldments, one on each side of the length of the vehicle. These weldments were time intensive critical welds, thus elimination of them is a real advantage.
The sponson is a horizontally flat piece from the front glacis, the glacis being a sloped plate at the front of the vehicle, to the back portion of the vehicle. The sponson is humped upwards at the front and rear of the vehicle due to the suspension modifications designed to improve cross country mobility. In the front, the sponson is humped upwards where the main drive sprocket has been rotated to a new angular position around the main drive input shaft. In the rear, it is humped upwards where the idler assembly has been raised. This rotation of the main drive sprocket and raising of the idler assembly have increased the clearance from the sprocket and the idler to the ground relative to the prior art vehicles, resulting in improved vertical obstacle crossing capability, and higher off-road cross country mobility.
REFERENCES:
patent: 3309759 (1967-03-01), Vittone
patent: 3730582 (1973-05-01), Lieffring
patent: 3754315 (1973-08-01), Heitman
patent: 3862490 (1975-01-01), Tsuneishi et al.
patent: 3909919 (1975-10-01), Miyabayshi et al.
patent: 4346930 (1982-08-01), Northey
patent: 4457555 (1984-07-01), Draper
patent: 4514891 (1985-05-01), Draper
patent: 4569554 (1986-02-01), Dodgen
patent: 4570321 (1986-02-01), Draper
patent: 4654946 (1987-04-01), Phillips
patent: 4662052 (1987-05-01), Draper
patent: 4847972 (1989-07-01), Anderson et al.
patent: 5490314 (1996-02-01), Riddle
patent: 5577311 (1996-11-01), Riddle
Braafladt Claude Philip
Burnham Harlan
Crosswhite Robert Owens
Greenlee Scott Alan
Grusonik William C.
Hughes S. Thomas
Kamp Ronald C.
Nguyen Trinh T.
United Defense L.P.
LandOfFree
Hull configuration of a modified tracked vehicle does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Hull configuration of a modified tracked vehicle, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Hull configuration of a modified tracked vehicle will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2553596