Manufacturing method of tensioning device for saw blade of woodworking band saw machine

At present, there are two types of saw blade tensioning devices of the known woodworking band saw machine: one type is a hydraulic (or pneumatic) tensioning device; The other type is mechanical tensioning device. The hydraulic (or pneumatic) tensioning device is realized by applying thrust to the shaft of a saw wheel of the band saw machine through a hydraulic cylinder (or air cylinder). The thrust can be displayed through an oil pressure gauge, and its size is easy to control and adjust. However, a complete set of hydraulic (or pneumatic) system is required, which is complex in equipment, large in floor area, energy-consuming in work, and is only suitable for large-scale woodworking band saw machines on a production line with high productivity. There are mainly two types of mechanical tensioners: one is heavy hammer lever type, and the other is spring type. The principle of the heavy hammer lever type tensioning device is that one end of the lever acts on the shaft of the saw wheel on the band saw machine through a mandril, and the other end is hung with a heavy hammer, so that the moment generated by the gravity of the heavy hammer acts on the shaft of the upper saw wheel, thereby realizing tensioning of the band saw blade. Its advantages are that no power is needed, the tensioning force of the saw blade in the sawing process is constant, but the magnitude of the tensioning force cannot be displayed, the weight adjustment of the heavy hammer is inconvenient, and the tensioning force is difficult to accurately adjust, and it is mainly used for large woodworking band saw machines. Spring-type tensioning device uses spring force generated by spring compression to act on the saw wheel shaft to tension the saw blade. Its structure is simple and easy to adjust, but it cannot show the magnitude of the tensioning force and is difficult to accurately adjust. It is commonly used in small and medium-sized bench woodworking band sawing machines such as joinery band sawing machines.

Technical implementation elements: The technical problem to be solved by the invention is to provide a saw blade tensioning device of a woodworking band sawing machine, which has simple structure, does not need power, can display the tensioning force instantly, and is accurate and convenient to adjust, aiming at the defects that the existing hydraulic (or pneumatic) tensioning device is complex in equipment, large in occupied area, energy-consuming and difficult to accurately adjust because the mechanical tensioning device cannot display the magnitude of the tensioning force. The inventor found in the research that the force borne by the hydraulic cylinder can be easily displayed by the oil pressure gauge for transmission of the internal hydraulic pressure. If a hydraulic cylinder is skillfully added on the basis of the existing spring type saw blade tensioning device, the tensioning force can be displayed in real time, and accurate adjustment of the tensioning force is convenient. Therefore, the technical scheme adopted by the invention is as follows: a tensioning device for a saw blade of a woodworking band saw machine comprises a screw rod nut mechanism and a spring, and is characterized by also comprising a hydraulic display device, wherein the hydraulic display device consists of a hydraulic cylinder, an oil pipe and an oil pressure gauge; The hydraulic cylinder is arranged between the spring and the screw rod of the screw rod nut mechanism, and oil in the hydraulic cylinder is connected with the oil pressure gauge through the oil pipe; Rotating the screw rod can adjust the acting force of the screw rod on the hydraulic cylinder to adjust the compression amount of the spring, and at the same time drive the connecting rod to adjust the heights of the upper saw wheel shaft and the upper saw wheel to adjust the tension degree of the saw blade, and the acting force on the hydraulic cylinder can generate pressure on the oil in the hydraulic cylinder, which is transmitted to the oil pressure gauge through the oil pipe to be displayed. The tension device also comprises a frame, wherein that frame comprise a guide rail; The guide rail guides the displacement of spring, hydraulic cylinder and nut slider. The frame is provided with an installation hole for installing the oil pipe.

In this way, the hydraulic cylinder is arranged between the spring and the screw rod nut mechanism, the screw rod can be rotated to tension or loosen the saw blade, and the oil pressure gauge displays corresponding values, so that the tension required by the saw blade can be conveniently adjusted. The tensioning device has a simple structure, the magnitude of the tensioning force can be displayed instantly, the tensioning force of the saw blade can be conveniently and accurately adjusted, no power is needed for tensioning the saw blade, and the tensioning device is particularly suitable for medium and small woodworking band sawing machines such as joinery band sawing machines and the like.