No abstract

The article reports that in order to improve the functional characteristics of the friction drive of vertical spindles, it was proposed to replace its conventional V-belts with poly-V-belts. Therefore, rollers with changed parameters are installed on the spindles, while maintaining the magnitude of the rolling radius of serial rollers. To determine the functionality of the new drive, a stand with a single spindle drum was created, which allows you to determine all the performance indicators of the polyline drive. The main task of research on this stand was to determine the possibility of creating a traction (friction) force of the drive that always exceeds the resistance force of a cotton bush clamped in a narrow working slot of the harvesting apparatus. To assess the functionality of a new version of the friction drive, a comparison technique was used when at the beginning the friction (thrust) force of a serial roller with a V-belt drive was measured, and then, on the stand-pull force of the drive with a poly-V-belt. A special device was made to measure the pulling force of the belts.

The article reports that to improve the functional characteristics of the friction drive of vertical spindles, it was proposed to replace its conventional V-belts with poly-V-belts. Therefore, rollers with changed parameters are installed on the spindles while maintaining the magnitude of the rolling radius of serial rollers. To determine the functionality of the new drive, a stand with a single spindle drum was created, which allows you to determine all the performance indicators of the polyline drive. The main research task on this stand was to determine the possibility of creating a traction (friction) force of the drive that always exceeds the resistance force of a cotton bush clamped in a narrow working slot of the harvesting apparatus. To assess the functionality of a new version of the friction drive, a comparison technique was used when, in the beginning, the friction (thrust) force of a serial roller with a V-belt drive was measured, and then, on the stand-pull force of the drive with a poly-V-belt. A special device was made to measure the pulling force of the belts.

We have in our previous articles that the unstable cotton-picking performance of the vertical spindle cotton picker is mainly due to the instability of the traction force of the V-belts of the friction drive of the spindles. The main reasons for this result were identified. The main reason for the value of the total pulling force of the V-belts in the friction serial drivee, which is why, due to the resistance forces of the cotton bush, the speed of rotation of the spindle often decreases at the time of extraction of the cotton slice from the sash. Therefore, the authors recommended replacing conventional V-belts with poly V-belts, the small wedges of which are installed on one, i.e. a single basis. Our experiments have shown that with the same tension of external belts, the pulling force of a multi-V belt with five wedges is always much greater than a standard set of three conventional V-belts on a serial drive. Consequently, poly-V belts always ensure the optimum angular velocity of the spindle, preventing the reduction of the completeness of the cotton harvest, which is very important. To do this, it was necessary to find some technical solutions for such a drive to function smoothly, in particular, the installation of a spindle speed stabilizer by the time the spindle reversal process was completed before it hit the external belts. Spindle, i.e. its roller, after it leaves the inner belt, rotates by inertia. The stabilizer has a block with an elastic surface, which, pressing against the spindle roller with a certain pressure, slows it down until it stops before the roller hits the beginning of the external belts, i.e. before the start of its reverse rotation. This article describes the design and effects of the stabilizer for the spindle roller to stop it at the right moment.

The article provides some information on the quality of cleaning the external friction (V-belt) drive, which drives the spindles of the vertical spindle of cotton picking machine, produced in the Tashkent Agricultural Tractor Plant. It is known that the main indicator for assessing the technological process of the cotton picking machine is the level of harvesting of ripe cotton. The degree of picking depends on many factors, the most important of which is that the amount of rotation velocity of the spindle around its axis, which meets the cotton ball, does not change. Factually, the degree of picking depends on the amount of absolute velocity of the spindle tooth, which acts like a double-sided blade, especially on its direction, as determined by previous fundamental research [1-4]. The absolute velocity of the tooth is the geometric sum of the working velocity of the machine in the field Vm , the rotational velocity of the spindle drum Vb and the rotational velocity Vsh given by the rotation of the spindle around its axis. It is explained that since the motor of a machine used in the field is always running at rated velocity, the values of Vm and Vb remain constant, but for various reasons, the angular velocity of the spindle, i.e. the rotational velocity of the tooth, remains the same as the constructor fixed. If the velocity of a single Vsh changes, the absolute velocity of the tooth will change, and in some cases it will not be possible that the tooth cannot grind cotton. In a horizontal-spindle cotton picking machine, the “rigid” drive, which transmits motion to the spindles, ensures that the angular velocity of the spindle in the spinning zone is always within the limits set by the constructer. Therefore, its picking rate does not change. The disadvantages of the vertical spindle device are that the Tashkent Agricultural Tractor Plant does not pay attention to the fact that its parameters do not meet the technical requirements in the production of the above-mentioned friction drive for the spindle. For example, the tension of the three piston belts in a friction drive is not controlled in the assembly shop. Due to the fact that the tension of the belts is not the same, the pressure exerted by the belts on the spindle roller, and therefore the frictional forces that rotate the spindle, will be different. When the spindle tooth is stuck to the cotton ball and the resistance to rotation is increased, the angular velocity of the spindle decreases and the direction of the absolute velocity of the tooth becomes uncomfortable. The article examines the tension of the outer straps of the friction drive in 28 new devices assembled at the plant and presents the results of the analysis.