Variable capacity-type gear pump designing method, design support program for the pump, design support device for the pump, and variable capacity-type gear pump

A variable capacity-type gear pump design support program for causing a computer to perform functions, comprising:

• constructing a numerical value calculation model for calculating an operation of a variable capacity-type gear pump including an inner rotor, an outer rotor, an outer ring that rotatably accommodates and holds the outer rotor, and a compression spring that controls movement of the outer ring;
• providing one or two or more temporary levers on the outer ring in the numerical value calculation model and assuming that contact points of the compression spring are located on the temporary levers;
• defining a movement rule of allowing the outer ring to perform translational movement, rotational movement, or a combination of the translational movement and the rotational movement;
• moving the outer ring based on the movement rule and calculating positional coordinate values of the contact points over the moving range to obtain moving trajectories;
• calculating a linearity index value from the moving trajectories;
• and
• determining appropriateness of the position of the temporary lever based on whether the calculated linearity index value is within a predetermined range of linearity index values.

A variable capacity-type gear pump design support device including a control unit, a data and command input unit, a storage unit, a calculation unit, and an output unit, the device performing:

• constructing a numerical value calculation model on the storage unit, the model calculating an operation of a variable capacity-type gear pump including an inner rotor, an outer rotor, an outer ring that rotatably accommodates and holds the outer rotor, and a compression spring that controls movement of the outer ring;
• providing one or two or more temporary levers on the outer ring in the numerical value calculation model and assuming that contact points of the compression spring are located on the temporary levers;
• defining a movement rule of allowing the outer ring to perform translational movement, rotational movement, or a combination of the translational movement and the rotational movement and storing the movement rule on the storage unit;
• moving the outer ring based on the movement rule in use of the calculation unit and calculating positional coordinate values of the contact points over the moving range to obtain moving trajectories;
• calculating a linearity index value from the moving trajectories in use of the calculation unit;
• and
• determining appropriateness of the position of the temporary lever based on whether the calculated linearity index value is within a predetermined range of linearity index values.

A variable capacity-type gear pump including an inner rotor, an outer rotor, an outer ring that rotatably accommodates and holds the outer rotor, and a compression spring that biases a lever provided on the outer ring to control movement of the outer ring, wherein

• in a numerical value calculation model for calculating an operation of the variable capacity-type gear pump including the inner rotor, the outer rotor, the outer ring, and the compression spring, one or two or more temporary levers are provided on the outer ring and it is assumed that contact points of the compression spring are located on the temporary levers,
• a movement rule of allowing the outer ring to perform translational movement, rotational movement, or a combination of the translational movement and the rotational movement is defined,
• the outer ring is moved based on the movement rule and positional coordinate values of the contact points over the moving range are calculated to obtain moving trajectories,
• the outer ring is configured so that the lever is provided at the position of the temporary lever associated with the trajectory satisfying a condition that the square of a correlation coefficient between variables which are the positional coordinate values is 0.9 or more, and
• the compression spring is provided on the trajectory in a direction identical to a direction of the trajectory, and makes contact with the lever.