Auxiliary clamp device for welding of vehicle brake steel backing

The invention discloses a vehicle brake steel backing welding auxiliary clamp device which comprises a mounting frame provided with a driving motor, a horizontal center shaft, at least one set of clamp units and an annular guide ring fixedly connected with the mounting frame and coaxially arranged with the center shaft. Each clamp unit comprises a base, a pair of clamp mechanisms, an opposite transmission component and a sliding part, an arc-shaped groove is formed in the arc-shaped outer wall of the base in a sunken mode, the clamp mechanisms are installed on the two sides of the base respectively, the opposite transmission component is used for being connected with the clamp mechanisms, and the sliding part is in sliding connection with the annular guide ring and is connected with the opposite transmission component, and a pair of limiting blocks is installed on the arc-shaped outer wall of the base; the side wall, facing the clamp unit, of the annular guide ring protrudes to form an inferior-arc-shaped fir