# US 2013/0154306 A1 · Aluminum flatbed with unique front connection > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0154306 A1 - Document ID: US20130154306A1 - Status: Published application - Kind: A1 - Application number: 13/768,240 - Filed: 2013-02-15 - Published: 2013-06-20 - Earliest claimed: 2008-01-04 - Assignees: Mac Trailer Manufacturing, Inc. - Inventors: James A. Maiorana; Denis Gosselin - Web page: https://patentgrep.com/patent/US20130154306A1 ## CPC - B62D 53/061: {of flat bed or low loader type or fitted with swan necks (detachable swan necks B62D53/065; swan neck-fifth wheel couplings B62D53/08)} - B62D 21/20: trailer type, i.e. a frame specifically constructed for use in a non-powered vehicle - B62D 27/065: {using screwthread (connection of crossbeam to A- pillars B62D25/147; mounting load bearing surfaces B62D21/09; securing mudguards B62D25/163; connections for synthetic parts B62D29/048)} - Y10T 29/49622: Vehicular structural member making - Y10T 29/49947: by applying separate fastener - Y10T 29/49968: Metal fusion joining - B62D: MOTOR VEHICLES; TRAILERS (steering, or guiding on a desired track, of agricultural machines or implements A01B69/00; wheels, castors, axles, increasing wheel adhesion B60B; vehicle tyres, tyre inflation or tyre changing B60C; connections between vehicles of a train or the like B60D; vehicles for use on rail and road, amphibious or convertible vehicles B60F; suspension arrangements B60G; heating, cooling, ventilating or other air treating devices B60H; windows, windscreens, non-fixed roofs, doors or similar devices, protective coverings for vehicles not in use B60J; propulsion plant arrangements, auxiliary drives, transmissions, controls, instrumentation or dashboards B60K; electric equipment or propulsion of electrically-propelled vehicles B60L; power supply for electrically-propelled vehicles B60M; passenger accommodation not otherwise provided for B60N; adaptations for load transportation or to carry special loads or objects B60P; arrangement of signalling or lighting devices, the mounting or supporting thereof or circuits therefor, for vehicles in general B60Q; vehicles, vehicle fittings or vehicle parts not otherwise provided for B60R; servicing, cleaning, repairing, supporting, lifting, or manoeuvring, not otherwise provided for, B60S; brake arrangements, brake control systems or parts thereof B60T; air-cushion vehicles B60V; motor-cycles, accessories therefor B62J, B62K; testing of vehicles G01M) - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A drop deck trailer frame includes a front section having a first upper surface, a rear section having a second upper surface lower than the first upper surface, and an improved connection between the front and rear sections which tends to reduce cracking which commonly occurs in drop deck trailer frames due to the stresses in the region of the connection. The connection preferably includes a semicircular weld. In addition, heat treated bent flanges are typically used to provide additional strength. Fasteners such as bolts are also typically used to connect various flanges. ## Claims ### Claim 1 A drop deck trailer frame comprising: a front section having a first upper surface; a rear section having a second upper surface lower than the first upper surface; an S-shaped flange on the front section; an I-beam of the rear section defining the second upper surface and comprising a vertical plate having a top and a bottom, an upper flange secured to the top of the vertical plate and having a front end, and a lower flange secured to the bottom of the vertical plate and having a front end; a first upwardly extending flange which extends from adjacent the front end of the upper flange to adjacent the front end of the lower flange; and a second upwardly extending flange which extends from adjacent the front end of the upper flange to adjacent the front end of the lower flange. ### Claim 2 (depends on 1) The frame of claim 1 wherein the second upwardly extending flange extends upwardly beyond the upper flange. ### Claim 3 (depends on 1) The frame of claim 1 wherein the lower flange of the I-beam is directly above a portion of the S-shaped flange. ### Claim 4 (depends on 1) The frame of claim 1 further comprising a plurality of bolts extending from the S-shaped flange to the lower flange of the I-beam. ### Claim 5 (depends on 1) The frame of claim 1 further comprising a connection member which is formed from a T-bar and includes a semicircular flat web and the first upwardly extending flange. ### Claim 6 (depends on 5) The frame of claim 5 wherein the semicircular web has a semicircular edge; and the vertical plate of the I-beam has a semicircular front edge which is secured to the semicircular edge of the web along a semicircular weld. ### Claim 7 (depends on 1) The frame of claim 1 wherein the I-beam comprises an inverted T-bar which includes the lower flange and a lower portion of the vertical plate; the I-beam comprises a T-bar which includes the upper flange and an upper portion of the vertical plate; and the lower and upper portions of the vertical plate are connected to one another along a substantially horizontal elongated weld. ### Claim 8 (depends on 7) The frame of claim 7 wherein the substantially horizontal elongated weld has a front end; and further comprising a semicircular weld which extends adjacent the front end of the substantially horizontal elongated weld. ### Claim 9 (depends on 8) The frame of claim 8 wherein the semicircular weld intersects the substantially horizontal elongated weld at the front end of the substantially horizontal elongated weld. ### Claim 10 (depends on 1) The frame of claim 1 further comprising a connection between the front and rear sections; and a semicircular weld on the connection. ### Claim 11 (depends on 10) The frame of claim 10 wherein the semicircular weld extends rearwardly from adjacent the front end of the upper flange and extends rearwardly from adjacent the front end of the lower flange. ### Claim 12 A drop deck trailer frame comprising: a front section having a first upper surface; a rear section having a second upper surface lower than the first upper surface; an S-shaped flange on the front section; an I-beam of the rear section defining the second upper surface and comprising a vertical plate having a top and a bottom, an upper flange secured to the top of the vertical plate and having a front end, and a lower flange secured to the bottom of the vertical plate and having a front end; an upwardly extending flange which extends from adjacent the front end of the upper flange to adjacent the front end of the lower flange; and an L-shaped flange adjacent the upwardly extending flange. ### Claim 13 (depends on 12) The frame of claim 12 wherein the L-shaped flange defines the first upper surface. ### Claim 14 (depends on 12) The frame of claim 12 wherein the L-shaped flange extends upwardly beyond the upper flange of the I-beam. ### Claim 15 (depends on 12) The frame of claim 12 wherein the L-shaped flange has a generally horizontal leg which is higher than the upper flange of the I-beam. ### Claim 16 (depends on 12) The frame of claim 12 further comprising an L-shaped plate; and a weld between the L-shaped plate and the L-shaped flange which secures the L-shaped plate to the L-shaped flange. ### Claim 17 (depends on 12) The frame of claim 12 further comprising a plurality of bolts extending from the L-shaped flange to the upwardly extending flange. ### Claim 18 (depends on 12) The frame of claim 12 further comprising a connection between the front and rear sections; and a semicircular weld on the connection. ### Claim 19 A drop deck trailer frame comprising: a front section having a first upper surface; a rear section having a second upper surface lower than the first upper surface; a longitudinally extending I-beam of the rear section defining the second upper surface and comprising a vertical plate having a top and a bottom, an upper flange secured to the top of the vertical plate and having a front end, and a lower flange secured to the bottom of the vertical plate and having a front end; a first upwardly extending flange of the rear section which extends from adjacent the front end of the upper flange to adjacent the front end of the lower flange and which has a lower end; a second upwardly extending flange of the front section which extends from adjacent the front end of the upper flange to adjacent the front end of the lower flange, which extends upwardly beyond the upper flange and which has a lower end; a longitudinally extending third flange of the front section which extends below the lower ends of the first and second upwardly extending flanges and includes a generally horizontal tongue which extends rearwardly beyond the lower ends of the first and second upwardly extending flanges and below the lower flange; a plurality of first bolts extending from the first upwardly extending flange to the second upwardly extending flange; and a plurality of second bolts extending from the tongue to the lower flange of the I-beam. ### Claim 20 (depends on 19) The frame of claim 19 further comprising a connection between the front and rear sections; and a semicircular weld on the connection.