US2941454A - Traffic intersection - Google Patents

Description

June 2l, 1960 A. o. cEDENo 2,941,454

TRAFFIC INTERSECTION Filed Oct. 21, 1957 2 Sheets-Sheetl 1 June 2l, 1960 A. o. cEDENo 2,941,454

TRAFFIC INTERSECTION Filed Oct. 21, 1957 2 Sheets-Sheekl 2 Affare O// Vero Cea/eno INVENTOR.

\ MMM m 5 fm@ TRAFFIC INTERSECTION Arturo Olivero Cedeno, Ocampo 1073, Monterrey, Mexico Filed Oct. 21, 1957, Ser. No. 691,375

6 Claims. (Cl. 94-1) This invention relates to traic intersections and more particularly to a trac circle for handling traic between a plurality of streets.

In traffic circles heretofore used it is necessary to turn onto and turn off of the trafnc circle at the outboard lane. Thus, while interior lanes are provided, their use*- fulness is greatly restricted and when they are used 1t is necessary for vehicles to be constantly shifting lanes While at the same time watching tralilc entering the circle. As entering traic must merge with traflic in the outboard lane, it is difficult to get onto a crowded traic circle.

By this invention there is provided a traffic c1rcle in which the problem of incoming merging tra'ic 1s eliminated, inside lanes are used, and traic can leave the circle from an inside lane. l

It is an object of this invention to provide a trailic circle in which cars may enter the circle Without merging with other traiic. l

Another object is to provide a trac circle 1n which cars do not shift between the several lanes of the circle.

Another object is to provide a traic circle in which cars may leave the circle from an interior lane without first emerging with traffic in an exterior lane.

Another object is to provide a traic circle in winch a car may enter the circle from any given street and exit onto any other given street without merging with other traic or changing lanes while in the circle.

Another object is to provide a tratic circle as in the preceding object for serving at least four streets in which traic is conveyed about the circle by a plurality of side-by-side winding lanes and the number of winding lanes at any one point is three less than the number of streets serviced by the circle.

Another object is to provide a multi-level trac circle in which automobile trafc is handled between all streets without merging traffic or shifting lanes and in which over-height vehicles, such as trucks, are handled separately to avoid the expense of spacing the levels a sufficient distance to accommodate over-height vehicles.

Other objects, features and advantages of this invention will be apparent from the drawings, the specication and the claims.

In the drawings vwherein there are shown by way of illustration several embodiments of this invention and wherein like numerals indicate like parts:

Figurevl is a plan view of a traic circle constructed in accordance with this invention and with a section of the upper level broken away to illustrate details of the lower levelthe streets of the intersection being numbered successively 1 through 8 and outgoing lanes of each street being numbered to indicate the origin of its traffic;

Figure 2 is a schematic view of a slightly modified form of intersection; and

Figure 3 is a schematic view of a further modified form of intersection.

The Figure l form of intersection of this invention is characterized by a plurality of side-by-side winding lanes 10 through 17. One lane is provided for each street serviced by the intersection and, therefore, their number will increase or decrease with the number of streets serviced by the intersection. The lanes 10 through 17 receive incoming traiiic from streets 1 through S, respectively, and convey it in a coiling or spiraling path toward the center of the intersection. In other words, each of the lanes 10 through 17 coil toward the center of the intersection. The intersection is so constructed that traffic does not switch between these lanes, and permanent barriers may .be erected between these lanes to prevent crossing of lanes.

The winding lanes 10 through 17 are provided at a common level and traic leaves these lanes by moving to another level after which it exits to the streets again without crossing lanes and in the preferred form without merging traic. Thus, it will be seen that the intersection is provided with an upper level indicated generally at 18 and a lower level indicated generally at 19. In the form of intersection illustrated the winding lanes are in the upper level.

Traffic leaves the Winding lanes of the upper level through a series of ramps leading to the lower level. One ramp is provided for each winding lane at circumferentially spaced points labout the intersection. These points correspond in number to the number of streets serviced by the intersection. Thus, the group of ramps indicated generally at 2l, -which may be designated 21a through 21e, provide for transferring traffic from each winding lane llt), and I3 through 17 to the lower level. In like manner the group of ramps indicated generally at 22 and comprising ramps 22a through 22e provide for transfer of traffic to the lower level just before reaching street No. 3. In like manner groups of ramps are provided about the circle for transferring trafic from the winding lanes of the upper level to each of the streets serviced by the intersection. These groups of ramps are shown at 23 through 23, and the individual ramps of each group are numbered in the same manner as explained in the discussion of groups 2,1 and 22.

Means for connecting the trac from each ramp at the lower level with the streets is provided. Preferably these lanes are sufficient in number to avoid merging traffic.

lReferring to the lanes of the lower level servicing street No. 5, it will be noted that separate lanes 29 through 35 are provided. These lanes may be considered as part of or as a continuation of ramps 23` through 28, and in the claims they are so considered. By tracing traflic in theA lower level, it will be noted that lane 29 conveys tralic from ramp 24e to a point outboard of the winding lanes and then proceeds with the winding lanes to a point adjacent street 6 where it turns under the incoming winding lane 15 and feeds traic onto the lane numbered 8 of i street 6. By handling one lane of traiiic in this manner, the winding lanes which are at an upper level may be reduced in length. If it is not desired to handle this trac in this manner, the winding lane 17 may be extended to a point opposite the termination of winding lane l0 and discharge its traffic on the opposite side of street 6, that is lane 8 of streetA 6 would be moved to the right-hand side of street 6 and would be adjacent the curb of street 6 in leaving `the traic circle. Traiiic from winding lane 17 Wishing to turn onto street 5 proceeds along lower level lane 30. In like manner, traiic from winding lanes 10, '11, 12 and 13 proceeds along lanes 31, 32, 33 and 34 to the outbound lanes of street 5.

in exactly the same manner eight times about the circle.

The illustrated form of circle as thus far explained han' Patente ,lune 2l, 196i)l dles tratic between any street and six of the other seven4 streets proceeding in a clockwise manner. Right turn traffic to the adjacent counterclockwise street is handled in a diierent manner. "However, it will be understood that if desired, the winding lanes could be continued another step to handle traicbetween all oi the streets serviced by the intersection.

It is preferred to construct the two levels of the traic circle with a clearance which will permit passenger cars only and to handle over-height vehicles, such as trucks, in a different manlief. For this purpose the traflic circle may be surrounded by a bridge 36 which functions in the manner of the usual traffic circle to handle over-height vehicles. Access ramps such as indicated at 37s'treet 5, provide for access and eiiit from the' surrounding bridge 36. This bridge also provides for right turn tr'ac between adjacent streets. While there will be sore merging ofntraic as right turn trafc moves onto bridge 36, it will be minor and unobje'ctionable. Right turn tratiic will leave the bridge in a special lane such as 'shown at 38, street 4, and no diiiculty will be experienced in leaving the bridge. WhileV the entry and exit ramps for cach street may be separated, it is preferred that they be sideby-side to minimize cost of the ramps leading to and from the bridge.

Thel handling of tratiic entering from street 5 is shown by lines of Vs and it will be traced here tofully explain the Way in which traiiic iiows on the circle. Tra'ic for each ofthe other streets is handled in the identical manner. A motorist desiring to turn from street 5 to street 4 goes up ramp 37 and proceeds to the right as indicated by the arrows and leaves in lane 38 of streetl 4. A motorist de'- siring to turn onto any of the other streets proceeds in the two outboard lanes numbered 5 onto winding lane 14. If it is desired to turn onto street V6, the ramp 25a is entered to drop to the lower level. From the lower level a lane 34 is provided which connects with the outgoing lane numbered 5 of street 6. If it is desired to leave the circle at street 7, the motorist continues along winding lane 14 to ramp 26h. A lane 33 connects ramp 26h with the outs going lane 5 of street 7. lf desired, the motorist may bypass ramp 26b and proceed to ramp 27C which leads to street 8. Ramp 27 is connected by a lane 32. with lanev numbered 5 of street 8. If desired, ramp 27C may be bypassed and the motorist may proceed to ramp 28d. By dropping down ramp 28d and proceeding along lane 31, the motorist may leave the circle and eXit on lane Svof street 1. Ramp 28d may be bypassed and the motorist may proceed along .winding lane 14 to ramp 21e. From ramp 21e the motorist may enter lane 30 to proceed to lane 5 of street 2., or he may enter lane 29 and proceed to lane 5 of street 3. in addition to the directional Vs, there is also shown a number of automobiles traveling like paths beginning at lane 6. The automobiles shownV in solid outline are in the upper level of the circle and those shown in dashed outline are in the lower level of the intersection.

Referring to Figure 2, there is shown a slightly modiiied form of circle. In this case, each of the Winding lanes extends a suicient distance to feed directly to the outgoing street from all down ramps, thus eliminating the lane 29 in the other intersection which proceeds along the outboard portion of the winding lanes to the next clockwise lane. Thus, taking lane 4i) by Way of example, it will be noted that traic enters this lane from street 41 by passing under the outer bridge 42 and then on to the upper level which is represented by solid lanes. Proceeding along lane 40 it will be noted that traic may drop to the lower level along ramp 43 to reach street 44. In like manner traic may drop on ramp 45 to reach street 46, ramp 47 to reach street 48, ramp 49 to reach street 50, ramp 51 to reach street 52, and ramp 53- to reach street 54; It will be noted that the ramps proceed to the lower level andv traic from the three outboard ramps ofv each group merge into a single line of outgoing traic while traft'lcfrom the three inboardY ramps of each group merges into a second single line of outgoing traflic. Truck and right turn traine to adjacent streets are handled on bridge 4Z in the same manner as explained in connection with Figure l.

The form of invention shown in Figure 2 provides for merging of trafc while leaving the circle, thus reducing trafiic to five lanes immediately upon reaching the street. Merging turning traffic is undesirable, and the Figure l form of invention which has a large number of outgoing lanes is preferred. Of course, the seven outgoing lanes may be merged int/ thiee outgoing lanes immediately after leaving the circle, preferably in a progressive manner to reduce lto lane traic on each street.

Referring now to Figure 3, there is shown a traffic circle constructed in accordance with this invention which follows generally the Figure 1 embodiment except that there are four streets serviced by the circle and the upper level of the Figure linters'ection is replaced by four individual bridgsSS, 56, 57 and 58. y Y

Each section of the'intersection is identical and, therefore, traic movement from only one street will be traced.

Considering traic owing intothe tr'ac circle from street 59, provision is made f or rright turn` t'raiiick by the U-shaped lane 61 which receives tratric from the curb lane of street 59 and discharges such traffic onto street 62;

Traic desiring to exit on either streets 63 or 64 proceeds on inbound lane 65 of street S9 to the traiic circle. As lane 65 reaches the circle, it is conveyed across thev other traic of the circle at this point at a different elevation, such as by bridge 5 5.

From bridge 55 incoming trahie proceeds along lane 66 of the tra'fhc circle. This lane extends less than 36() degrees, in the caset a symmetrical intersection approxi= matelyA degrees, to street 64;

`As lane 66 of tlie traffic circle reaches the next adjacent street 63, it crosses the incoming trahie from street 63 at a diierent level as by bridge S6 which con; Veys the incoming trahie from street 63 over lane 66. After passing" through bridge 56, thetrafc in lane 66 may divideV and turn left into lane 67 to proceed ontbound on street 63 or may proceed to the right on a continuation of lane 66 to street 64.

As traic in lane 66 reaches .st-reet 64, it again crosses the incoming traffic at aA different level as by bridge 57 and empties onto street 64 in llane 68.

From the abovev it will be seen that there hasV been provided a very simple four-street intersection in which there is no merging traiiic and in which only four bridges are needed to convey traic to and from each intersection without merging traffic.

The foregoing' disclosure and description of the irrvention is illustrative andeirplanatoryfthereof and vari= ous changes may be' made within the scope of the appended claims without departing from the spiritV of the invention.

I claim:

l. A traflic' interchange comprising, a `traffic circle and a plurality of streets radiating therefrom, said traf'- fic circle comprising, a plurality of spiraling side-byside lanes on one level, each of said lanes beginning at the outboard of said circle at progressively spaced points,-

outboard of said circle at progressively spaced points in' the vicinity of' said radiating streets, entranceramps interconnecting each of said streets with the outboard eains.

end of a corresponding spiraling lane, and exit ramps departing from spaced points on each of said spiraling lanes and connecting each of said spiraling lanes with a plurality of said radiating streets, each of said exit ramps crossing the contiguous spiraling lanes outboard of said spaced points at an elevation diierent from the elevation of the spiraling lanes.

3. A traffic interchange comprising, a traflic circle and a plurality of streets radiating therefrom, said trafiic circle comprising, a plurality of spiraling side-byside lanes on an upper level, each of said lanes beginning at the outboard of said circle at progressively spaced points in the vicinity of said radiating streets, entrance ramps interconnecting each of said streets with the outboard end of a corresponding elevated lane, and downwardly extending exit lanes departing from spaced points on each of said spiraling lanes and connecting each of said spiraling lanes with a plurality of said radiating streets, each of said downwardly extending ramps passing under the contiguous elevated lanes outboard of said spaced points.

4. The traffic interchange of claim 3 wherein all of the exit ramps leading from the spiraling lanes at one angular position about the circle with the exception of the exit ramp servicing the inboard spiraling lane leading to one street, said ramp servicing the inboard spiraling lane extending to the exterior of the circle and thence about the circle to the next adjacent street.

5. The trac interchange of claim 3 wherein the spiraling lanes spiral toward the center in one circular direction and a lane extends in the opposite direction References Cited in the le of this patent UNITED STATES PATENTS 1,543,080 Graves .Tune 23, 1925 1,689,161 Skultin f Oct. 23, 1928 FOREIGN PATENTS 546,268 France Aug. 17, 1922 686,433 France Apr. 14, 1930 736,887 Germany July 1, 1943 940,788 France Tune 7, 1948 806,019 Germany June 11, I1951 OTHER REFERENCES Roads and Streets, pp. 205-206, May 1932.

A Policy on Arterial Highways in Urban Areas, Bur. Public Roads, July 1956, Figs. J-19(a) and J-l9(c).

A Policy on Arterial Highways in Urban Areas, American Assoc. of State Highways, 1957, page 511.

Engineering News-Record, July 11, 1957, pp. 38 and 39.

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