OBRABOTKAMETALLOV Vol. 23 No. 3 2021 MATERIAL SCIENCE EQUIPMENT. INSTRUMENTS 6 1 4 mechanism (11) is located inside the lever system. The purpose of this mechanism is to bring the system of levers and rods to a certain position, which contributes to their setting parameters, when installing a set of cams and heddle frames [44]. Relocating the eccentric mechanism (11) from the lever system to the body side is suggested. In this case, it will be possible to change the positions of the fi xed axes and reduce the distances between the axes of the double-arm levers and the roller shaft. Due to the change in these positions, the dimensions of the levers and rods will change, which will require a new synthesis of the lever system. The reduction in the dimensions of the mechanism is due to the removal of the mechanism for fi xing the position of the heddle (eccentric mechanism) from the area of the lever system. This solution allowed for the reduction of the distance between the O2 and O3 axes. As a result of the change in these parameters, the synthesis of the attached structural groups was necessary. Some of the elements, such as the doublearm lever FO4E and the slider G, which is a heddle shaft, will not change their geometric parameters. The fi xed axes of the mechanism’s kinematic scheme are marked in Fig. 2. The O2 axis is at a distance of 151 mm from the origin, the O3 is at a distance of 311 mm from the O1 axis, the dimension of the O2 B lever is 192.5 mm. Due to the new position of the axes, the levers O2B, O3C, and O3 D, as well as the rod BC, should be changed, and their values should be obtained as a result of synthesis. In addition, the angle of the doublearm lever AO2B should be reduced by 35 degrees so that it does not take up much space when defl ected. The lever mechanism is synthesized assuming that it starts from the last link, which is responsible for the stroke provided by the amount of heddle lifting. For instance, the stroke of the fourth heddle shaft should be 75 mm [1, 19]. The symmetry of the heddle stroke relative to the horizontal axis was chosen as the main criterion for synthesis. Thus, for the fourth heddle shaft, it was 37.5 mm. According to the technical documentation, the lever has a size of O4E = 138.5 mm. Then, for the fourth heddle shaft, the value of the angle is μ 1 (see Fig. 2). 1 4 arctan 2 EE O E μ æ ¢ ö÷ ç ÷ = ç ÷ ç ÷ çè ⋅ ø , (1) where EE´= 75 mm. Fig. 1. The design scheme of the heddle motion consists of several components, including a two-arm lever (1), a hub (2), a body (3), a shaft (4), a top arm (5), a roller lever (6), eccentric drive (7), a bottom arm (8), a horizontal rod (9), a connecting rod (10), eccentric mechanism (11)
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