Soldering device

A soldering device comprising:

• an adjustment member for changing a width between conveying rails to match a size of a conveying substrate to be soldered,
• wherein the adjustment member includes:
• a screw shaft that rotates;
• a nut having a flange portion for connection, a fixed position of the nut to the screw shaft being changeable forward or backward by rotating the screw shaft;
• and
• a rail-supporting member for supporting a rail which conveys the substrate, the rail-supporting member being fixed to the nut through the flange portion for connection and changing the width between the conveying rails to match the size of the conveying substrate,
• wherein the nut contains a screw portion from a forward end thereof to a rear end thereof and includes at least one non-meshing part along whole thereof, the non-meshing part does not mesh with the screw shaft, and
• wherein when changing the width between the rails for conveying the substrate by rotating the screw shaft, an adhered matter which is adhered to the screw shaft and is fixed thereto is scrapped by a ridge of the non-meshing part due to the rotation of the screw shaft.