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"TRICAR".  A  multipurpose  car  for  everyday  use.  The  optimum  scheme  of  disposition  of  seats.


Shulga V.I.

The car constructed under this scheme will enable, in numerous cases, to do without constructive and functionally redundant vehicles constructed along standard "2+2" scheme of seats disposition. On the other hand, the proposed scheme enables to overcome functional insufficiency of "half-size" 2 seat variants.

The car with a simplified body (a motorized transport platform - the carriage) constructed along this scheme can replace, with a number of basic operation advantages, such universal, operative vehicle as a motorcycle with a sidecar.


Two seats (the driver and one passenger) are placed in the standard way - in parallel - in a line (in the interaxle space).

The third seat is placed behind, crosswise, flush with the first two (in the "hole" between rear wheels), with an exit backward (through a back wall, a door, a niche). Fig.1.


EXPLANATORY NOTE. A justification of rationality and uniqueness of the proposed scheme.

One of the principal requirements to a modern car is a minimum dimension. Rather uneasy to enter the conventional 4-seat scheme in the frameworks of this requirement. It is necessary to economize on the size of seats and free space for legs. Convenience of access to seats is sacrificed. The second line, sometimes, is reduced till the "children" sizes. Doors here are made narrower. Frequently, it is suggested to do without these doors at all.

Thus as the statistician displays, the private car transports, on the average, by different estimations 1,7-1,9 persons for time. The averaged percent frequency of quantitative loading of the city car is shown on fig.2.


In this connection, attempts to solve the problem of creation of the optimum car on the basis of 2 seat schemes seem to be quite natural. However, such decision results to that the car in 20-25 %% cases appear functionally insufficient. Such insufficiency (expectation of such insufficiency) does not allow to admit this variant as universal, leaves its in the category exotic.

Adding of one more seat essentially raises a degree of functional adequacy of the automobile. A 3-seat car is already capable to satisfy the majority of trips - 90-95 %%. Practice displays that number 3 is a certain "magic number" defining the maximum size of a mobile, dynamical, easy and naturally casually ("spontaneously)" gathering amount of people. Such amount of seats also should have a universal vehicle of private use. 4 persons demand already qualitatively others - stronger motives, occasions and principles for "collecting". The transport problem here should be solved either in parallel or sequentially, or means of other class.

Rationality (optimality) of the three-seat car is defined also by fundamental geometrical feature of construction of vehicles in general. The rectangular shape of a transport platform has the greatest spreading. This circumstance is a consequence of property of rectangles to be simply and compactly integrated with each other, and, in general, - to fill-in densely a plane. For this reason, containers, furniture, locations, structures, etc., etc., as a rule, have the rectangular shape in the plan.

Thus, the objective reality, basically, gives us four sides - the generalized Doors for access into the internal space of a transport platform. The front, on a course, side the Door, on a number of the obvious reasons, appears rather inconvenient for arrangement of entrance-exit. Three walls rest: two side and one back near every of which one seat should be installed in the considered "minimum" case (two in the standard way, and one behind, along the back)...

Thus it is possible to make a conclusion in general the unique constructive functional rationality of 3 seat cars with an exit backward.

As the pilot model it is possible to consider automobiles, which rear seats, have transversal disposition (for example, GAZ-69A). Their essential difference from proposed variant is that seats are placed in the body under which bottom the rear axle with suspender unit is situated (fig.3a).


Such arrangement results in a number of essential objective and subjective inconveniences and deficiencies. The barycentre of the machine lifts up, its dimensions are augmented. Access to "uplifted" seats is inconvenient. It is uncomfortable to sit on them: there are an increased range of the oscillations caused by irregularities of road, and these seats appear less protected (out of overall dimensions).

A difference of the proposed decision consists that the additional seat is suggested to be disposed flush with the main ones (in the "hole" between rear wheels - fig. 3b). "Maximum board" suspendsion of rear wheels, with "maximum bottom" constructional elements is supposed.

As a first approximation here it is suggested the independent suspension of rear wheels on the longitudinal levers which are looking like plates situated on their edges (fig.4).


At one end of each such lever the dowel-shaft for a wheel is placed. On the opposite end the vertical damper with a spring fastens. All this is installed from the same side as the wheel, in wheel niches. On the center, each lever rigidly fastens to a butt of its transverse axles, rocking in the bottom plane. Torsion can be used as these axles. They will undertake all loading or its part.

Forward drive is assumed to be the most preferable here. The engine can be located in front or longitudinally, on the center, between the driver and first passenger.

As a result of all these design solutions, we obtain one more low-sited seat with convenient access. All machine turns out compact and enough comfortable...

Rationality of the proposed Scheme is also confirmed by its comparison to such known vehicle what is a motorcycle with a sidecar. This machine also satisfies the requirements of constructive simplicity, optimum amount of seats and easy access to them.

In this connection it is necessary to tell, that production of an elementary, open, doorless body of Jeep type (a transport platform-carriage), basically, not much more difficult than production of a frame of heavy motorcycle and its sidecar (or a load box of a tricycle). Such body-carriage is a set of panels with the reinforcement ribs, strengthened by design structures (tubes, for example), which form a frame as the whole, or its separate rudiments. The engine and gear box in the considered three-seat variant basically (on power) should be a similar class.

Thus, at expenditures of the comparable order, we obtain a same universal, operative, mobile, small-size vehicle as a motorcycle without its essential deficiencies...

Certainly, possibilities of realization of the proposed seat scheme are not limited only to this variant. Generally, the family of machines of different classes is planed. The transport platform-carriage with the engine of low power, small wheels, cargo space can be covered with a soft coverlet. "Jeep" with boards, without doors, with wind shield and collapsible tent, the engine of the same power, that one of a heavy motorcycle. Further, - the same as previous, with the elementary cabin and doors. And, at last, the car with a high-grade cabin, a panoramic windshield, with movable door glasses etc., etc. - up to the "lux" variant. .

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At realization of the proposed seat scheme the following design decisions seems to be expedient.

It is necessary to place the third seat from the opposite side from the driver on the reasons of saving of centering at free second seat.

A spare wheel is placed on the back wall (door) on the outside of the seat (for the insurance at a possible rear-end collision).

A fuel tank is installed from below, within the framework of transversal "trapezoidal wave" of the bottoms under seats of the driver and first passenger.

Passenger seats are demountable, for placing of cargo.

It is necessary to provide attachment nodes for various trailers and semitrailers, and, in particular, resting on with the arc on the center of the back between the wheels.

In case of the central disposition of a power aggregate there is place for luggage on the low jacket, between forward wheels.

For the variant without rigid cabin ("Jeep").

The tent roof, folded as "accordion" in the cross direction to the center, and downlifted on the central collapsible racks downwards for backrests of armchairs of the driver and first passenger. In the uplifted condition the head side of the tent should fasten to the upper side of the windshield frame. It is necessary to provide a possibility to downlift the tent in the opened condition on the level of boards, for the period of long parking. Thus backrests of armchairs should be lowered on sets. The fold steering tube is rather pertinent here. In the latter case, the windshield can be thrown back, under the lowered tent. In the uplifted condition, from under the tent the shutters can be installed fasten from below to boards, leaving free only apertures for entrance-exit, or in general only for sight.

It is necessary to provide a possibility of the further, additional complete set of an elementary demountable cabin ("roof-board"), and, then, - the elementary doors.

Also it is necessary to provide additional folding seats-"shelves", or, at least, to make flat from above housings of rear wheels (with soft mouldings), for seating two passengers towards each other, in extreme cases.

It is seemed to be expedient to work a question of substitution of a gear box on a stepless wedge-belt variator, extremely pertinent in this case. The space for its placement is present - in legs, between the driver and passenger. Except for known objective operation advantages, stepless drive essentially simplifies logics of vehicle driving that can considerably expand a community of its users. Those who can be named "women, old men and children" would come much more easy and inclinativelly in this community and, in general all for whom driving of the car is not a pleasure but a necessity. Moreover, driving of the car with variator can become a pleasure for them too.

Arrows-"markers" of the current direction of forward wheels placed somewhere in the jacket plane can be rather useful in this sense (anyway, for the tutoring period).

Simplification of driving logics can appear very opportunely for professionals too - in intense (extreme) situations.

As one of points of advertising, it is possible to mark that the considered seat scheme enables mutual conversations, for example, on the current, operative problems.

It is seemed to be expedient to experiment with a small turn of the rear armchair in the movement direction.

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