# Analysis and Test of the Tillage Layer Roll-Type Residual Film Recovery Mechanism
## 2 Materials and Methods  
### Structures and Working Principle  
The roll-type residual film recovery mechanism for the tillage layer is mainly composed of a suspension mechanism, a gearbox, a film-lifting device, a pickup roller, a roller, a film-unloading wheel, and a frame. Its structure is shown in Figure 1. The winding roller is installed on the pickup roller. According to the operation area, the circumferential direction of the pickup roller can be divided into a film-picking area, in which the winding roller rotates forward, and a film-unloading area, in which the winding roller rotates reversely.  
During the operation of the roll-type residual film recovery mechanism for the tillage layer, the machine is towed forward by the tractor through the suspension mechanism, the power output shaft of the tractor drives the gearbox to rotate, and the power is transmitted to the film-lifting device to drive the film-lifting device to rotate counterclockwise so that the film-soil mixture with a depth of 150 mm in the plow layer is thrown. Moreover, the film-lifting operation of the plow layer residual film is achieved. The power from the gearbox is directed to the pickup roller and unloading wheel of the film through the transmission device, facilitating the counter-rotational movement of the former. The film-unloading wheel rotates clockwise, and the winding roller is driven by the double-row chain through the transmission chain to perform the forward rotation film-picking operation in a forward rotation film-picking area and performs reverse rotation in a reverse film-unloading area to coordinate with the film-unloading operation of the film-discharging wheel.  
The essential component of the plow layer residual film recovery machine is the winding roller, with its structure outlined in Figure 2. During operation, the film lift device ejects a mixture of soil and film, which is then propelled toward the forward rotation film-picking area thanks to the soil retaining plate. Moreover, the movement direction of the drive spring -tooth is the same as the falling direction of the film-soil mixture by self-weight  
Figure 1: Schematic diagram of the whole machine structure (1, suspension mechanism; 2, gearbox; 3, film-lifting device; 4, frame; 5, retaining plate; 6, roller; 7, double chain drive; 8, pickup roller; 9, film-unloading wheel; 10, diaphragm tank; 11, hydraulic motors).  
under the action of rotation of a winding roller. Finally, the effective film-picking operation is achieved by using a tooth tip hook of the spring-tooth to roll the residual film. The movement direction of the spring-tooth is the same as the falling direction of the film-soil mixture, and the speed of the spring-tooth is greater than the falling speed, which can effectively reduce the reaction force of the soil on the residual film in the process of picking up the film by the spring-tooth and is beneficial to improving the cleaning rate. The winding roller continues to rotate along with the pickup roller. When the winding roller moves to the film-unloading area, the winding roller rotates reversely. The movement direction of the spring-tooth is the same as that of the film-unloading wheel, and the residual film is easy to strip when the spring-tooth moves reversely. Thus, the film-unloading capacity is further improved under the mechanical force of the film-unloading wheel.