Constant weight meter and sample conveying device thereof

The invention discloses a constant weight meter and a sample conveying device thereof. The sample conveying device of the constant weight meter comprises an annular conveying line, a drive mechanism and a bearing part, wherein the lengthways width of the annular conveying line is adjustable, the drive mechanism is connected with the annular conveying line in transmission mode, and used for enabling the annular conveying line to perform circulation motion along the trajectory direction of the annular conveying line, the bearing part comprises a bearing end and a connection end which are oppositely arranged, the bearing end is provided with a bearing port used for bearing a container containing a sample to be measured, and the connection end is used for connecting the annular conveying line.The sample conveying device of the constant weight meter is high in space usage rate and small in occupied space, and accordingly the constant weight meter which uses the sample conveying device is small in size and saves sp