A supplying device of fixed colorants volume for a colorant dispenser, comprising:
- a colorant source;
- a cylinder body having multiple piston cylinders arranged around a circumferential direction thereof;
- a swashplate having an oblique surface and arranged substantially coaxially with the cylinder body, and configured to be capable of rotating around a longitudinal axis thereof and relative to the cylinder body;
- multiple piston mechanisms, wherein each piston mechanism comprises a piston rod and a piston connected to the piston rod, the piston rod has a rolling abutment structure abutting against the oblique surface, and the piston is configured to be capable of making a stroke movement in the corresponding piston cylinder by means of rotation of the swashplate;
- an actuator for actuating the swashplate;
- a controller operatively connected to the actuator to control the amount of rotation of the swashplate;
- an outlet for dispensing a colorant;
- and
- an axial reset mechanism for biasing the rolling abutment structure towards the oblique surface along an axial direction;
- a circumferential reset mechanism capable of applying a circumferential restoring force to the rolling abutment structure during rotation of the swashplate, so as to make the rolling abutment structure tend to restore a predetermined abutment state with the oblique surface, wherein the stroke movement of each of the pistons comprises a first stroke and a reverse second stroke, in the first stroke, the piston cylinder of the piston is in communication with the colorant source so as to draw the colorant from the colorant source, and in the second stroke, the colorant drawn from the colorant source is discharged out of the piston cylinder;
- a moving valve plate disposed near outlets of the piston cylinders, the moving valve plate is arranged coaxially with and synchronously rotates with the swashplate, and the moving valve plate including a first structure defining a colorant channel that fluidly connects the colorant source to a first part of the piston cylinders, a second structure allowing the colorant to be discharged from a second part of the piston cylinders, and a third structure used for covering a third part of the piston cylinders, wherein the pistons in the first part of the piston cylinders are in the first stroke, the pistons in the second part of the piston cylinders are in the second stroke, and the pistons in the third part of the piston cylinders are at a top dead center or a bottom dead center between the first stroke and the second stroke;
- a fixed valve plate disposed between the moving valve plate and the cylinder body, the fixed valve plate not rotating with the swashplate and having a fixed position relative to the cylinder body, the fixed valve plate including a first opening and second openings, the first opening fluidly connected to the colorant source and configured to provide the colorant to the colorant channel of the moving valve plate, the fixed valve plate having a respective one of the second openings for each of the pistons, wherein the colorant channel of the moving valve plate fluidly connects the first opening of the fixed valve plate to each of the second openings of the fixed valve plate that corresponds to one of the pistons of the first part of the piston cylinders, and the colorant being provided from the colorant source to each one of the pistons of the first part of the piston cylinders by flowing from the color source through the first opening, the colorant channel, and the one of the second openings corresponding to the piston;
- and
- a zero position indicating mechanism used for indicating a zero position of rotation of the swashplate relative to the cylinder body, wherein
- wherein the moving valve plate has a thickness, the colorant channel is a groove in a side of the moving valve plate that faces the fixed valve plate, and the groove extends through less than the entire thickness of the moving valve plate.