Constant pressure valve for inflatable product and inflatable product

A constant pressure valve comprising:

• a housing defining therewithin an airflow channel,
• a first sealing seat disposed in the airflow channel and a first through hole formed through the first sealing seat;
• and
• an inflation valve core comprising:
• a first actuating assembly comprising:
• a first pressure-bearing plate having a first side that faces the airflow channel and a second side opposite the first side;
• a first elastic member connected to the second side of the first pressure-bearing plate;
• and
• a first valve stem connected to the first side of the first pressure-bearing plate;
• wherein the first valve head is disposed on the first valve stem;
• and
• wherein, upon action of an inflation pressure, the first pressure-bearing plate moves against a pressure of the first elastic member,
• a first valve head,
• wherein the first actuating assembly is configured to drive the first valve head to disengage from the first through hole, or to engage with the first through hole in a sealing manner,
• wherein the constant pressure valve is switchable between an inflation state in which the first valve head is disengaged from the first through hole and the airflow channel is unblocked;
• and a cut-off state in which the first valve head is engaged with the first through hole in a sealing manner, and the airflow channel is blocked by the first valve head;
• a first piston chamber defined within in the housing, wherein the first elastic member is mounted in the first piston chamber, and the first pressure-bearing plate seals the first piston chamber and is reciprocable relative to the first piston chamber in an axial direction of the first piston chamber;
• a second sealing seat disposed in the airflow channel in an upstream direction of the first sealing seat, and a second through hole formed through the second sealing seat;
• an air intake valve core disposed in the upstream direction of the inflation valve core, the air intake valve core comprising:
• a second actuating assembly comprising:
• a second pressure-bearing plate having a first side that faces the airflow channel and a second side opposite the first side;
• a second elastic member connected to the second side of the second pressure-bearing plate;
• and
• a second valve stem connected to the first side of the second pressure-bearing plate;
• wherein the second valve head is disposed on the second valve stem;
• and
• wherein, upon action of the inflation pressure, the second pressure-bearing plate moves against a pressure of the second elastic member;
• and a second valve head;
• wherein the second actuating assembly is configured to drive the second valve head to disengage from the second through hole, or to engage with the second through hole in a sealing manner;
• wherein the constant pressure valve is further switchable into an initial state in which the second valve head is engaged with the second through hole in a sealing manner and the airflow channel is blocked by the second valve head;
• wherein in the inflation state, the second valve head is disengaged from the second through hole;
• and
• wherein in the cut-off state, the second valve head is engaged with the second through hole in a sealing manner, and the airflow channel is blocked by the second valve head.