Oil cup assembly of air enforceing pump

The utility model discloses an oil cup assembly for air boosting pumps, which comprises an oil storage cup, an oil cup cover a filter screen positioned inside the oil storage cup, and a rubber bladder partition arranged between the top of the oil storage cup and the oil cup cover to form a vacuum chamber between the rubber bladder partition and the oil cup cover. The vacuum chamber is communicated with the external atmosphere via a vacuum-pumping passage, and the volume of the vacuum chamber changes along with the movement of the rubber bladder partition. An external thread is arranged on the top of the oil storage cup. A vent channel is arranged at the inside bottom of the oil cup cover. The oil cup cover has an internal thread fitting with the external thread of the oil storage cup, and the internal thread is intermittent with thread open slots communicated with the vent channel. The vacuum-pumping passage (7) is defined by the vent channel and the thread open slots. With the arrangement, the utility model avoids the invasion of air dust and moist into the braking fluid, protects the braking fluid from being contaminated by air dust and moist, and prevents the occurrence of oil injection promptly upon braking, thereby ensuring the stability of brake performance.