Diaphragm pump
A diaphragm pump converts rotation of a motor into a reciprocating motion and drives a diaphragm. The diaphragm pump includes a partition configured to form a pump chamber together with a deformation portion of the diaphragm, a suction passage communicating with the pump chamber via a suction through hole extending through the partition, and a suction valve configured to open/close the suction passage. The valve body of the suction valve includes a leak structure configured to form a channel between the valve body and the seat surface of the partition.
1. A diaphragm pump comprising:
a diaphragm including a deformation portion having a cup shape;
a partition configured to close an opening portion of the deformation portion and form a pump chamber together with the deformation portion;
a suction through hole extending through the partition;
a suction passage communicating with the pump chamber via the suction through hole;
a discharge through hole extending through the partition;
a discharge passage communicating with the pump chamber via the discharge through hole;
a driving mechanism configured to convert rotation of a motor into a reciprocating motion and alternately deform the deformation portion in a direction of increasing a capacity of the pump chamber and in a direction of decreasing the capacity of the pump chamber;
a suction valve attached to the partition and configured to open the suction passage in a stroke of increasing the capacity of the pump chamber and close the suction passage in a stroke without increasing the capacity; and
a discharge valve attached to the partition in the discharge passage and configured to open the discharge passage in a stroke of decreasing the capacity of the pump chamber and close the discharge passage in a stroke without decreasing the capacity,
the driving mechanism includes a crank body fixed to a rotating shaft of the motor, and a driving body connected to the crank body via a driving shaft tilting with respect to the rotation shaft of the motor,
the driving body includes a shaft portion connected to the driving shaft, and an arm portion extending from the shaft portion outward in a radial direction and connected to the deformation portion of the diaphragm,
wherein the partition includes a seat surface on a side facing the pump chamber, and
the suction valve includes a valve body configured to come into contact with or separate from the seat surface, and the valve body includes a leak structure configured to form a channel between the valve body and the seat surface and leak fluid in the pump chamber through the channel to the suction passage.
2. The diaphragm pump according to claim 1 , wherein
the valve body includes a seal surface facing the seat surface, and
the leak structure includes an unevenness provided on the seal surface.
3. The diaphragm pump according to claim 2 , wherein the unevenness is provided all over the seal surface.
4. The diaphragm pump according to claim 2 , wherein the unevenness is an unevenness formed by transferring a shape of a molding surface for emboss processing, which is provided on a mold used to mold the valve body.
5. The diaphragm pump according to claim 1 , wherein the seat surface is a smooth surface.