RU219529U1 - Undercarriage of a military tracked vehicle - Google Patents

Abstract

The utility model relates to the field of transport engineering, specifically to military tracked vehicles (VGM) with an aft drive wheel, which can be operated on soils of low bearing capacity. The undercarriage of the VGM is made of six rollers and contains caterpillars with rubber-metal hinges, rubber-coated road wheels mounted on the sides of the VGM hull, balancers directed in the direction of travel, torsion bars located across the hull, and support rollers. What is new is that the undercarriage is made with the possibility of additional loading of the first track roller by 5-10% and the sixth track roller by 30-40% relative to the uniform load on the rollers, which is 1/12 of the mass of the VGM in a free installation position without tensioning the caterpillar, and uniform distribution of the remaining mass of the VGM between the inner rollers from the second to the fifth. The technical result of the utility model is the creation of a VGM undercarriage scheme that provides increased cross-country ability on soft soils. 2 w.p. f-ly, 4 ill.

Description

The utility model relates to the field of transport engineering, specifically to military tracked vehicles (VGM) with an aft drive wheel, which can be operated on soils of low bearing capacity, such as a swampy meadow, peat-silty bogs, virgin snow, etc.

Medium tanks T-72, T-90 and T-80 are known, having a mass of 44 to 47 tons (see B. S. Safronov, V. I. Murakhovsky “Modern tanks”, M .: Arsenal-Press, 1995 .). The undercarriage of the tanks is designed in accordance with the recommendations set out in the book (L. V. Sergeev “Theory of a Tank”, edition of the Academy of Armored Forces, 1973), and contains six rubber-coated double-row rollers per side, a caterpillar with a parallel-type RMSH and a drive wheel located at the rear of the machine. The location of the drive wheel in the aft part, from the point of view of the dynamic loading of the caterpillar bypass, is advisable for caterpillar vehicles operating under conditions of high traction (see V.F. Platonov. “Dynamics and reliability of the caterpillar mover”, M .: Mashinostroenie, 1973 ., p. 23).

However, with the rear drive wheel (VK) in modern tracked vehicles, when driving on soft soils, there is a significant redistribution of loads under the rollers, the occurrence of an uneven load on the ground and a deterioration in ground clearance (see V. F. Platonov. “Dynamics and reliability of a caterpillar mover“ M.: Mashinostroenie, 1973, p. 29).

The chassis of the T-72 tank (hereinafter referred to as the product) was chosen as a prototype (see B.S. Safronov, V.I. Murakhovsky “Modern Tanks”, M .: Arsenal-Press, 1995 p.), containing a six-roller on board caterpillar undercarriage with RMSH and a hull, in the bow of which the control compartment is located, and in the aft part there is an engine-transmission compartment and a drive wheel. In order to reduce the dynamic loads of the first suspensions of the road wheels, their torsion bars are set higher, the rest of the torsion bars are located on the same level. The balancers of all suspensions are directed in the direction of travel back.

In a free state, a product with mass G creates a load on the ground under the rollers without tension of the caterpillar, except for the first one, uniform and equal to 0.0875 × G = 1.05 × G / 12. On the first roller, the load is 29% less than under the others and is 0.0628 × G = 0.75 × G / 12,

Track pretensioning reduces the ground loads from the outer (1st and 6th) road wheels and increases the loads under the inner road wheels (from 2nd to 5th).

When the product moves, as a result of a change in tension in the working and free branches of the caterpillar from traction, there is a further redistribution of pressure along the length of the support branch, with the greatest loads occurring under the penultimate track rollers, because from the action of the traction force, the rear (6th) track roller is pulled closer to the body and reduces the pressure on the ground, and the penultimate roller is additionally loaded. Table 1 shows the nature of the load change under the prototype track rollers, calculated from the condition of pre-tensioning the tracks in a static state and additionally acting traction force.

It is well known that the pretensioning force is equal to T _C \u003d 0.5G × f ₁ and is selected from the condition of the most probable resistance when the VGM moves along loose sand, where f ₁ \u003d (0.15 ÷ 0.20) \u003d 0.17 is the drag coefficient when moving (L. V. Sergeev “Theory of a Tank”, edition of the Academy of Armored Forces, 1973, p. 66).

The operating traction force Р _rods =0.65G×f ₂ is selected from the most severe conditions of the running caterpillar when driving on a slope with soft soil such as a swampy meadow, where f ₂ =0.25 is the coefficient of resistance during movement.

Thus, initially in statics without pre-tensioning the tracks, the load under the first track roller of the prototype is 62.8G×10 ^-3 , under the remaining 87.5G×10 ^-3 and the condition 0.75:1.05:1.05:1 is met ,05:1.05:1.05 (see column 2 of tab. 1) relative to the load on the ground, equal to 1:1:1:1:1:1, where 1 is taken to be the load corresponding to a uniform load on all rollers equal to 0 .08333G = G/12 The total load on board is 0.5G.

In statics with pretension (see column 3 of tab. 1), the total bead load is 0.5G. In motion, the loads under the road wheels of the most loaded side when moving along the slope are given (see column 4 of Table 1), the total load on the most loaded side is 0.65G.

However, the prototype does not have sufficient patency on soils with a weak bearing capacity.

The technical result of the utility model is the creation of a VGM undercarriage scheme that provides increased cross-country ability on soft soils.

The technical result is achieved by the fact that the undercarriage of the military tracked vehicle is made of six rollers and contains tracks with rubber-metal hinges, rubber-coated road wheels mounted on the sides of the VGM hull, balancers directed in the direction of travel, torsion bars located across the hull, and support rollers, according to useful model, the undercarriage is made with the possibility of additional loading of the first track roller by 5-10% and the sixth track roller by 30-40% relative to the uniform load on the rollers, which is 1/12 of the mass of the VGM in a free installation position without tensioning the caterpillar, and uniform distribution of the remaining VGM mass between the inner rollers from the second to the fifth.

In this case, the track rollers can be made double-row when used on medium and heavy tanks, for example, tanks T-72, T-90, T-80.

At the same time, the track rollers can be made single-row when used on such VGMs as the BMP-1, BMP-2, BMP-3 infantry fighting vehicles, the BTR-50P amphibious tracked armored personnel carrier, as well as on civilian tracked vehicles, for example, on a conveyor tractor MT-L, MT-LB.

The analysis of the distinguishing features showed the following:

- implementation of the undercarriage of the conveyor with the possibility of additional loading of the first track roller by 5-10% and the sixth track roller by 30-40% relative to the uniform load on the rollers, which is 1/12 of the mass of the conveyor in a free installation position without tensioning the caterpillar, and uniform distribution the remaining weight of the conveyor between the inner rollers from the second to the fifth. At the same time, the condition 1.05÷1.10: 0.9125÷0.875: 0.9125÷0.875: 0.9125÷0.875: 0.9125÷0.875: 1.30÷1.40 is observed, which ensures the reduction of loads under track rollers of the undercarriage and, as a result, increases its patency on soils of low bearing capacity.

It should be noted that initially in statics without pre-tensioning the track, the load under the track rollers corresponds to: under the first roller - 105÷110%, under the sixth roller - 130÷140% of the uniform load, which is 83.33G×10 ^-3 , the remaining load is distributed evenly between the inner rollers (see column 2 of tab. 2), the total load on the side is 0.5G.

Table 2, column 3 shows the distribution of loads under the rollers, the total load on the side is 0.5G. Table 2 column 4 shows the distribution of loads under the rollers for driving in the most difficult conditions of the slope, the total load on the most loaded side is 0.65G.

The essence of the utility model is illustrated by drawings, where:

- figure 1 shows the running gear VGM, side view;

- in Fig. 2 shows the installation position of the balancers with track rollers;

- in Fig. 3 shows a two-row track roller with solid tires;

- in Fig. 4 shows a single-row track roller with a solid tire.

The undercarriage is located symmetrically relative to the VGM body (see Fig. 1) and contains a caterpillar 1 with a rubber-metal hinge of a parallel or sequential type, six rubber-coated road wheels 2, for example, double-row, (see Fig. 3) with a diameter of 750 mm (tank roller diameter ). The balancers 3, connecting the torsion bars 4 and road wheels 2, are located in the direction of travel back. Torsion bars 4 are located at the same level relative to the housing. In the aft part there is a drive wheel 5, in the bow part there is a guide wheel 6 with a tension mechanism (not shown in Fig. 1). Chassis has support rollers 7.

The undercarriage may have single-row road wheels with solid tires (see Fig. 4).

When assembling the undercarriage of the conveyor (see Fig. 2), the installation dimensions of the balancers 3, which determine the positions of the road wheels 2 from the second to the fifth, relative to the installation line of the torsion bars 4, are set the same, and the load on the roller corresponds to 1/12 of the weight of the conveyor. The installation dimensions of the balancers of the first and sixth rollers are assigned in such a way that the load on the first one is 5-10% and the seventh rollers are 30-40% more than the uniform load under the rollers. Thus, in the initial position, when the track tension is zero, the outer track rollers perceive a large load and unload the middle rollers (table 2, column 2). Track tension reduces the load under the outer rollers and loads the middle rollers (table 2 column 3). When moving, the tractive force redistributes the load on the ground under the track rollers by pulling the sixth roller to the line of installation of torsion bars and subsidence of the remaining rollers from the current load (table 2 column 4).

From tables 1, 2 it can be seen that in the claimed chassis, the ground clearance in motion is higher due to a more uniform distribution of loads under the road wheels.

So for the prototype, the loads vary from 0.0330×G to 0.1325×G, the spread of values is 0.0995×G.

In the proposed chassis - from 0.0616×G to 0.1233×G, with a spread of values equal to 0.0617×G.

Scatter ratio = 0.62 and thus, the uneven load on the track rollers decreased by 38.0%, which is effective for increasing the cross-country ability of conveyors when operating on soils with low bearing capacity (see the book edited by V. F. Platonov “Crawler transporters-tractors ". M .: Mashinostroenie. 1978, p. 24).

Thus, the claimed utility model achieves a technical result - the creation of a chassis scheme for a military tracked vehicle with increased cross-country ability on soft soils.

Claims (3)

1. The undercarriage of a military tracked vehicle (VGM), made of six rollers and containing tracks with rubber-metal hinges, rubber-coated road wheels mounted on the sides of the VGM hull, balancers directed in the direction of travel, torsion bars located across the hull, and support rollers, characterized in that that the undercarriage is made with the possibility of additional loading of the first track roller by 5-10% and the sixth track roller by 30-40% relative to the uniform load on the rollers, which is 1/12 of the mass of the VGM in a free installation position without tensioning the caterpillar, and uniform distribution the remaining mass of the VGM between the inner rollers from the second to the fifth. 2. Chassis according to claim 1, characterized in that the track rollers are made in two rows. 3. Chassis according to claim 1, characterized in that the track rollers are made single-row.

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