Constant-temperature heater for 3D printer

The utility model relates to the technical field of constant-temperature heaters, and discloses a constant-temperature heater for a 3D printer, which comprises a cabinet body, the inner wall of the cabinet body is provided with a transverse groove, the inner wall of the transverse groove is in sliding connection with a placing frame, the middle part of the placing frame is provided with a sliding groove, and the inner walls of the left and right sides of the sliding groove are in sliding connection with sliding blocks; a bidirectional threaded rod is in threaded connection with the middles of the two sliding blocks, clamping teeth are fixedly connected to the upper ends of the two sliding blocks, a plurality of grooves are formed in the sides, close to each other, of the two clamping teeth, a rotating disc is fixedly connected to the left end of the bidirectional threaded rod, and a fixing column is fixedly connected to the inner wall of the right side of the cabinet body. According to the utility model, the