1. An injection device for administering a liquid medicine to a patient, comprising a main body, a liquid medicine container, a needle and a removable unit, wherein the liquid medicine container is installed inside the main body and connected to the needle, and the removable unit comprises a contact surface provided with through hole and adjacent to the skin of the patient when performing the injection, and the needle is installed with the possibility of passage through the through hole. 2. An injection device according to claim 1, wherein the removable unit comprises a sensor configured to determine the position of the connection of the contact surface with the skin of the patient. The injection device according to claim 1, which comprises a mechanism for moving the container with the liquid drug in the direction of the contact surface from the first position to the second position, or in the direction from the contact surface from the second position to the first position. The injection device according to claim 2, which comprises a mechanism for moving the container with the liquid drug in the direction of the contact surface from the first position to the second position, or in the direction from the contact surface from the second position to the first position. The injection device according to claim 3, in which the needle is installed in the needle assembly, and the removable unit comprises paws configured to hold the needle assembly in the through hole while moving the container with liquid medicine from the first position to the second position to automatically connect the needle to the specified container and with the possibility of uncoupling the needle assembly. 6. Injection device according to claim 4, c1. Инъекционное устройство для введения пациенту жидкого лекарственного средства, включающее основную часть, емкость с жидким лекарственным средством, иглу и съемный блок, при этом емкость с жидким лекарственным средством установлена внутри основной част
