Automatic lubricating system

The invention provides an automatic lubricating system. The automatic lubricating system involves a hydraulic drive grease pump, a hydraulic control reversing valve, a distributor, a grease tank, an oil cylinder and a wedge block set, wherein an oil inlet of the system is connected with a working oil port of the reversing valve of a main machine; an oil path A and an oil path B of the system communicate with the oil cylinder; the oil cylinder is connected with the wedge block set and is used for driving the wedge block set to act; the oil path A and the oil path B are provided with the hydraulic drive grease pump; and the hydraulic drive grease pump is connected with the distributor and the grease tank through the hydraulic control reversing valve correspondingly, the distributor outputs grease to the wedge block set, and lubrication of the wedge block set is achieved. According to the automatic lubricating system, a hydraulic-drive and hydraulic -control type grease injection mode is adopted, the function of