A material conveying device, comprising: a material conveying groove, having a traveling track; a material bearing and conveying assembly, comprising: an annular chain; traveling units, the traveling units are scrapers, which are arranged on the chain at intervals, wherein the traveling units are able to be driven by the chain to move on the traveling track along a material conveying direction, and each traveling unit is provided with a bottom surface close to the material conveying groove, a top surface opposite to the bottom surface and side surfaces extending between the top surface and the bottom surface; a belt-shaped elastic material-bearing portion, connected to the top surfaces of the two adjacent traveling units, or connected to the top surfaces and the side surfaces of the two adjacent traveling units; and a driving device, being able to drive the chain to rotate cyclically to move along the material conveying direction relative to the material conveying groove; characterized in that a middle part of the elastic material-bearing portion is arched; and the elastic material-bearing portion is arched in a direction away from the material conveying groove, when connected to the two adjacent traveling units. a material conveying groove, having a traveling track; a material bearing and conveying assembly, comprising: an annular chain; traveling units, the traveling units are scrapers, which are arranged on the chain at intervals, wherein the traveling units are able to be driven by the chain to move on the traveling track along a material conveying direction, and each traveling unit is provided with a bottom surface close to the material conveying groove, a top surface opposite to the bottom surface and side surfaces extending between the top surface and the bottom surface; a belt-shaped elastic material-bearing portion, connected to the top surfaces of the two adjacent traveling units, or connected to the top surfaces and the side surfaces of the two adjacent traveling units; and a driving device, being able to drive the chain to rotate cyclically to move along the material conveying direction relative to the material conveying groove; characterized in that a middle part of the elastic material-bearing portion is arched; and the elastic material-bearing portion is arched in a direction away from the material conveying groove, when connected to the two adjacent traveling units. an annular chain; traveling units, the traveling units are scrapers, which are arranged on the chain at intervals, wherein the traveling units are able to be driven by the chain to move on the traveling track along a material conveying direction, and each traveling unit is provided with a bottom surface close to the material conveying groove, a top surface opposite to the bottom surface and side surfaces extending between the top surface and the bottom surface; a belt-shaped elastic material-bearing portion, connected to the top surfaces of the two adjacent traveling units, or connected to the top surfaces and the side surfaces of the two adjacent traveling units; and a driving device, being able to drive the chain to rotate cyclically to move along the material conveying direction relative to the material conveying groove; characterized in that a middle part of the elastic material-bearing portion is arched; and the elastic material-bearing portion is arched in a direction away from the material conveying groove, when connected to the two adjacent traveling units.