Abstract: A sand spreader includes a sand storage chamber. Two sand discharge ports are disposed below the sand storage chamber, and are an upper-layer staggered sand discharge port and a lower-layer sand pressing plate sand discharge port, respectively. The upper-layer staggered sand discharge port comprises a left side sand discharge plate and a right side sand discharge plate configured to intersect with each other. Horizontal staggered ports are formed in a position at the bottom of the two sand discharge plates, and vertical spacing between the staggered ports is adjustable. Also comprised is the lower-layer sand pressing plate sand discharge port, including left and right side sand pressing plates. Vertical sand discharge ports are disposed between the sand pressing plates on the two sides, and the width of the vertical sand discharge ports is adjustable, so as to further facilitate control over the amount of discharged sand.

Abstract: A unidirectional or bidirectional sand dispensing device, including a discharge port (10), the discharge port includes a lower plate (11) and an upper plate (12), the upper plate is provided above the lower plate, an included angle between a horizontal plane and a straight line where an endpoint of a free end of the upper plate and an endpoint of a free end of the lower plate are located is a leakage angle (13), that is to say, a particulate material forms an inclined plane between the upper plate and the lower plate, and an included angle between the inclined plane and the horizontal plane is the leakage angle, which can be adjusted by changing relative positions of the upper plate and the lower plate. The direction of an opening of the sand passing passage is opposite to a moving direction during the sand dispensing operation.

Abstract: A 3D printing apparatus and a 3D printing method are provided. The 3D printing apparatus includes a frame, and a working area is formed in the frame; a powder spreading device, a printing device, and a moving device are disposed in the working area; the powder spreading device and the printing device are simultaneously driven by the moving device to move in a staggered manner along different moving paths, wherein a powder spreading of the powder spreading device and a printing of the printing device are achieved at a same time. A technical problem in the prior art that a printing efficiency of the 3D printing apparatus is greatly limited resulting from that because powder spreading and printing are completed successively at different steps, time needs to be spent on waiting and a long period is spent on printing after powder spreading on each layer is solved.

Abstract: A unidirectional or bidirectional sand dispensing device, including a discharge port (10), the discharge port includes a lower plate (11) and an upper plate (12), the upper plate is provided above the lower plate, an included angle between a horizontal plane and a straight line where an endpoint of a free end of the upper plate and an endpoint of a free end of the lower plate are located is a leakage angle (13), that is to say, a particulate material forms an inclined plane between the upper plate and the lower plate, and an included angle between the inclined plane and the horizontal plane is the leakage angle, which can be adjusted by changing relative positions of the upper plate and the lower plate. The direction of an opening of the sand passing passage is opposite to a moving direction during the sand dispensing operation.

Abstract: A sand spreader includes a sand storage chamber. Two sand discharge ports are disposed below the sand storage chamber, and are an upper-layer staggered sand discharge port and a lower-layer sand pressing plate sand discharge port, respectively. The upper-layer staggered sand discharge port comprises a left side sand discharge plate and a right side sand discharge plate configured to intersect with each other. Horizontal staggered ports are formed in a position at the bottom of the two sand discharge plates, and vertical spacing between the staggered ports is adjustable. Also comprised is the lower-layer sand pressing plate sand discharge port, including left and right side sand pressing plates. Vertical sand discharge ports are disposed between the sand pressing plates on the two sides, and the width of the vertical sand discharge ports is adjustable, so as to further facilitate control over the amount of discharged sand.