| 摘要 |
PROBLEM TO BE SOLVED: To provide an ink jet recorder having a pump unit capable of suppressing fluctuation of a load torque for supplying a negative pressure to a capping device and being reduced in size. SOLUTION: The pump unit comprises two pump wheels 110, 111 which are rotated by a driving force from a driving means and two pulleys 101-104 which are rotatably attached to grooves 115-118 on the pump wheels 110, 111, respectively. The two pulleys 101-104 squeezes tubes 92, 93 in a frame 91 by being positioned symmetrically about the rotation center of the pump wheels 110, 111 in one rotational direction and are separated from the tubes 92, 93 in the other rotational direction. The maximum contact regions between the tubes 92, 93 and the pulleys 101-104 in the pump frame are set in a range of 160-180 degrees. |
