Small adjustable large-damping linear damper

The invention provides a small adjustable large-damping linear damper which comprises a bottom support, a damper shell, a damper piston module, a damper end cover module, a top support and a spring supporting module, the damper piston module comprises a piston rod, a flow velocity valve, a one-way valve and a piston piece, the piston piece is fixed to the piston rod, and the flow velocity valve is fixed to the lower portion of the piston piece; flow velocity holes with different hole diameters are machined in the flow velocity valve. A flow hole and a one-way hole are machined in the piston piece, the flow hole is close to the piston rod, the one-way hole is formed along the edge of the piston piece, and a one-way valve is fixed below the one-way hole. Convex points are further processed on the flow velocity valve and can be clamped into grooves in the lower part of the piston sheet, so that the flow velocity hole is aligned with the flow hole; the damping coefficient is adjusted by adjusting the aperture siz