Diaphragm pump and liquid discharge apparatus including diaphragm pump

A liquid discharge apparatus comprising:

• a liquid discharge head configured to discharge liquid;
• a housing configured to house the liquid discharge head inside;
• a liquid reservoir container configured to reserve liquid;
• and
• a diaphragm pump that is arranged outside the liquid discharge head and inside the housing,
• wherein the diaphragm pump includes:
• an actuator including a first surface and a second surface that is a back surface of the first surface,
• a first diaphragm bonded to the first surface and a second diaphragm bonded to the second surface,
• a first pump chamber that faces the first diaphragm, and that is formed on a side of the first surface,
• a second pump chamber that faces the second diaphragm, and that is formed on a side of the second surface,
• a first inlet port through which flowing fluid flows into the first pump chamber,
• a first outlet port through which flowing fluid flows out of the first pump chamber,
• a second inlet port through which flowing fluid flows into the second pump chamber, and
• a second outlet port through which flowing fluid flows out of the second pump chamber,
• wherein the diaphragm pump is configured to deform to change a volume of the first pump chamber and a volume of the second pump chamber so that fluid flows,
• wherein, when the first diaphragm and the second diaphragm are displaced convexly in a direction to the first pump chamber, the second pump chamber is configured to expand and the first pump chamber is configured to contract so that fluid flows into the second pump chamber and fluid flows out of the first pump chamber,
• wherein, when the first diaphragm and the second diaphragm are displaced convexly in a direction to the second pump chamber, the first pump chamber is configured to expand and the second pump chamber is configured to contract so that fluid flows into the first pump chamber and fluid flows out of the second pump chamber, and
• wherein the first diaphragm and the second diaphragm are different in stiffness.

A liquid discharge apparatus comprising:

• a liquid discharge head unit including a liquid discharge head configured to discharge liquid,
• wherein the liquid discharge head includes a diaphragm pump,
• wherein the diaphragm pump includes:
• an actuator including a first surface and a second surface that is a back surface of the first surface,
• a first diaphragm bonded to the first surface and a second diaphragm bonded to the second surface,
• a first pump chamber that faces the first diaphragm, and that is formed on a side of the first surface,
• a second pump chamber that faces the second diaphragm, and that is formed on a side of the second surface,
• a first inlet port through which flowing fluid flows into the first pump chamber,
• a first outlet port through which flowing fluid flows out of the first pump chamber,
• a second inlet port through which flowing fluid flows into the second pump chamber, and
• a second outlet port through which flowing fluid flows out of the second pump chamber,
• wherein the diaphragm pump is configured to deform to change a volume of the first pump chamber and a volume of the second pump chamber so that fluid flows,
• wherein, when the first diaphragm and the second diaphragm are displaced convexly in a direction to the first pump chamber, the second pump chamber is configured to expand and the first pump chamber is configured to contract so that fluid flows into the second pump chamber and fluid flows out of the first pump chamber,
• wherein, when the first diaphragm and the second diaphragm are displaced convexly in a direction to the second pump chamber, the first pump chamber is configured to expand and the second pump chamber is configured to contract so that fluid flows into the first pump chamber and fluid flows out of the second pump chamber, and
• wherein flowing liquid flows out of the first outlet port and the second outlet port to the liquid discharge head and flowing liquid flows from the liquid discharge head into the first inlet port and the second inlet port.