Oil suction device of vehicle

Abstract

An oil suction device of a vehicle has a mechanical oil pump and includes an air suction unit. The air suction unit includes a first communication passage, a second communication passage, and an opening and closing mechanism. The first communication passage communicates with an atmosphere side. The second communication passage communicates with a suction unit of the oil pump. The opening and closing mechanism is capable of switching between opening and closing of communication between the first communication passage and the second communication passage. When an oil suction pressure of the oil pump becomes a negative pressure lower than or equal to a predetermined pressure, the opening and closing mechanism is opened to cause air sucked through the air suction unit to be mixed into oil which is sucked from an oil reservoir through a suction pipe.

What is claimed is: 
     
         1 . An oil suction device of a vehicle, the oil suction device having a mechanical oil pump which is driven by rotation transmitted from a driving source of the vehicle and configured to suck and pump oil in an oil reservoir to the oil pump, the oil suction device comprising
 an air suction unit which is provided in a suction section in which oil in the oil reservoir is sucked by a suction unit of the oil pump,   the air suction unit including a first communication passage which communicates with an atmosphere side, a second communication passage which communicates with the suction unit of the oil pump, and an opening and closing mechanism which is capable of switching between opening and closing of communication between the first communication passage and the second communication passage,   wherein when an oil suction pressure of the oil pump becomes a negative pressure lower than or equal to a predetermined pressure, the opening and closing mechanism is opened to cause air sucked through the air suction unit to be mixed into oil which is sucked from the oil reservoir through a suction pipe.   
     
     
         2 . The oil suction device of a vehicle according to  claim 1 ,
 wherein the opening and closing mechanism includes:   a valve element configured to open and close between the first communication passage and the second communication passages; and   an urging unit configured to urge the valve element to a closed position,   wherein when the oil suction pressure of the oil pump becomes a negative pressure lower than or equal to the predetermined pressure, the valve element moves against an urging force of the urging unit from the closed position to an open position.   
     
     
         3 . An oil suction device of a vehicle, comprising:
 a mechanical oil pump to be driven by a driving source of the vehicle and having a suction portion;   a first conduit connected to the suction portion of the mechanical oil pump;   a second conduit connected to an oil reservoir; and   an air suction device comprising:
 a first communication passage which communicates with an atmosphere side; 
 a second communication passage which communicates with the first conduit and the second conduit; and 
 an opening and closing mechanism configured to connect or disconnect the first communication passage and the second communication passage, the opening and closing mechanism connecting the first communication passage and the second communication passage in a case in which an oil suction pressure in the oil pump becomes a negative pressure lower than or equal to a predetermined pressure. 
   
     
     
         4 . The oil suction device of a vehicle according to  claim 3 ,
 wherein the opening and closing mechanism includes a valve element configured to connect or disconnect the first communication passage and the second communication passages, and an urging device configured to urge the valve element to a closed position at which the first communication passage and the second communication passages are disconnected, and   wherein when the oil suction pressure of the mechanical oil pump becomes a negative pressure lower than or equal to the predetermined pressure, the valve element moves against an urging force of the urging device from the closed position to an open position at which the first communication passage and the second communication passages are connected.   
     
     
         5 . The oil suction device of a vehicle according to  claim 3 ,
 wherein when a pump rotation rate of the mechanical oil pump is higher than or equal to a predetermined rotation rate, the oil suction pressure of the mechanical oil pump becomes a negative pressure lower than or equal to the predetermined pressure.