1. An electronic component mounting device comprising:an electronic component insertion device that inserts an electronic component into a board from one side of the board within a component mountable region that is set in advance; and
a viscous fluid applying device that applies a viscous fluid to the board from the other side of the board in parallel with insertion of the electronic component into the board by the electronic component insertion device,
wherein the viscous fluid applying device includes (a) at least one flow tank that accommodates the viscous fluid and ejects the viscous fluid, and (b) a flow tank moving device that moves each of the at least one flow tanks to not only the component mountable region, but also a region outside the component mountable region,
wherein the region outside the component mountable region includes a maintenance region in which at least one maintenance operation is performed on at least one of the flow tanks,
wherein the electronic component mounting device includes a maintenance device that performs maintenance of the flow tank which is an object of maintenance from the least one flow tank, and
wherein the maintenance device includes (a) an inspection unit that performs inspection of the flow tank that is the object of maintenance and (b) an inspection unit moving device that is able to move the inspection unit between the standby position and an inspection position at which inspection of the flow tank, which is in the maintenance region and is the object of maintenance, is able to be performed.