JPH1162853A - Fuel oil pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent pressure of oil within a chamber from abnormally rising and prevent an increase in power consumption of a fuel oil pump by providing an oil passage guiding limited oil within the chamber by the tip face of a projection and a slot to a discharge chamber. SOLUTION: A rotor 67 oscillates within a cavity portion 64, bringing the outer peripheral surface into linear contact with the inner peripheral surface of the cavity portion 64 because a rotary shaft 5 revolves, and a projection 68 reciprocates within a slot 69 according to the oscillation. Next, oil within a oil reservoir is sucked within a suction chamber 70 via a suction passage 74, a hole and a suction port, and oil within a discharge chamber 71 is forcibly fed to fuel oil passage 52 via a discharge port, a hole, a discharge passage 77 and a hole 78. Oil within a chamber 80 flows to the discharge chamber 71 through a groove 91 and at the same time a part of oil enters the fuel oil passage 52 through a notch 92 and an oil hole 93. Therefore, power consumption of a fuel oil pump 60 can be prevented from increasing because the pressure rise in oil within the chamber 80 can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil supply pump suitable for a closed scroll compressor or the like.

[0002]

2. Description of the Related Art An example of a conventional hermetic scroll compressor is shown in FIG. The inside of the closed housing 8 is partitioned by a discharge cover 31 into a high-pressure side 44 and a low-pressure side 45. A scroll type compression mechanism C is provided above the low pressure side 45.
Is provided, and an electric motor M for driving the motor is provided below.

The electric motor M comprises a rotor Ma and a stator Mb. The rotor Ma is fixed to the rotating shaft 5, and the stator Mb is fixed by press-fitting the housing 8.

The scroll type compression mechanism C includes a fixed scroll 1, an orbiting scroll 2, a frame 6, a rotation preventing mechanism 3,
A drive bush 54, a swing bearing 73 and the like are provided.

The fixed scroll 1 has an end plate 11 and a spiral wrap 12 erected on the inner surface thereof. A discharge port 13 is formed in the center of the end plate 11.

The orbiting scroll 2 includes an end plate 21 and a spiral wrap 22 erected on the inner surface of the end plate 21. A drive bush 54 is provided with a drive bush 54 in a boss 23 erected at the center of the outer surface of the end plate 21. It is rotatably fitted via 73.

An eccentric pin 53 projecting from the upper end of the rotary shaft 5 is slidably fitted in a slide hole 55 formed in the drive bush 54. A plurality of closed spaces 24 are formed by displacing the fixed scroll 1 and the orbiting scroll 2 by a predetermined distance from each other and engaging them with each other at an angle shifted by 180 degrees.

The frame 6 is fixed to a sealed housing 8, and the orbiting scroll 2 is slidably supported on the frame 6. Between the orbiting scroll 2 and the frame 6, a rotation preventing mechanism 3 including an Oldham link or the like for allowing the orbiting scroll 2 to revolve and prevent the rotation is provided.

The fixed scroll 1 is fastened to the frame 6 by bolts 32, and the relative position is regulated by a plurality of positioning pins 33.

At the center of the outer surface of the end plate 11 of the fixed scroll 1, a cylindrical flange 16 projects upward, and a cylindrical projecting projection extends downward from the outer peripheral surface of the flange 16 and the lower surface of the discharge cover 31. O with the inner peripheral surface of the flange 38
A discharge cavity 42 is formed by tightly fitting through a ring 39, and a suction chamber 43 is formed outside the discharge cavity 42.

A discharge hole 46 communicating with the discharge cavity 42 is formed in the center of the discharge cover 31, and the discharge hole 46 is opened and closed by a discharge valve 47. One end of the discharge valve 47 and one end of the valve retainer 48 are fixed to the outer surface of the discharge cover 31 by bolts 49.

The upper end of the rotary shaft 5 is supported by an upper bearing 84 provided on the frame 6, and the lower end is supported by a lower bearing 85 provided on the stay 15.

When the electric motor M is driven, the orbiting scroll 2 is driven via the rotating shaft 5, the eccentric pin 53, the drive bush 54, the orbiting bearing 73, and the boss 23. While being blocked, it revolves around a circular orbit having the radius of revolution.

Then, the gas enters the low-pressure side 45 via the suction pipe 82 and passes through the passage (not shown) from the suction chamber 43 to the closed space 24.
Inhaled into. Then, as the volume of the closed space 24 decreases due to the revolving orbiting motion of the orbiting scroll 2, the compressed space reaches the center portion while being compressed, and then the discharge valve 13 is discharged from the discharge port 13 through the discharge cavity 42 and the discharge hole 46. It is pushed open to enter the high pressure side 44, from which it is discharged to the outside via the discharge pipe 83.

At the same time, the oil in the oil sump 86 limited to the bottom of the closed housing 8 is sucked up by the oil supply pump 60 and passes through the oil supply passage formed in the rotary shaft 5 to form the upper bearing 84, the lower bearing 85, It is supplied to the slewing bearing 73 and other sliding parts.

The details of the refueling pump 60 are shown in FIG.
Is a longitudinal sectional view, (B) is a sectional view taken along line BB of (A), (C)
(A) is an arrow view along the CC line of (A).

A circular recess having a predetermined depth is formed on the lower surface of the lower bearing 85.
A bore 62 is drilled and the cavity 64 is limited by covering this recess 62 with a thrust plate 63 which is in close contact with the lower surface of the lower bearing 85. This thrust plate 63 is provided with a lower bearing 85 by a plurality of bolts 66 together with a cover 65 which is in close contact with its lower surface.
Has been concluded.

A rotor 67 is accommodated in the cavity 64, and an eccentric shaft 5a formed below the rotary shaft 5 is inserted into a hole 68 formed in the center of the rotor 67 so as to be relatively rotatable. ing. The lower end surface of the eccentric shaft portion 5a is in contact with the upper surface of the thrust plate 63.

The outer circumferential surface of the rotor 67 extends radially.
The protrusions 68 are protruded, and the suction chamber 70 is limited on one side of the protrusion 68 by inserting the tip of the protrusion 68 into a slot 69 formed in the inner peripheral surface of the cavity 64. Discharge chamber on the side
71 is limited.

The suction chamber 70 communicates with the oil sump 86 through a suction port 72, a hole 73 formed in the thrust plate 63, and a suction passage 74 formed in the cover 65, and the discharge chamber 71 communicates with the discharge port 75, Thrust plate
Hole 76 formed in 63 and discharge passage formed in cover 65
77, the oil supply passage 52 formed in the center of the rotary shaft 5 is communicated through a hole 78 formed in the thrust plate 63.

A relief valve 79 is attached to the lower surface of the cover 65, and the relief valve 79 communicates with the discharge passage 77 in the middle.

When the eccentric shaft portion 5a rotates in the direction of the arrow around the axis of the rotating shaft 5 as the rotating shaft 5 rotates, the rotor 67 has its outer peripheral surface in line contact with the inner peripheral surface of the cavity 64. Swings in the cavity 64 and the protrusion 68
Reciprocate in 69.

Accordingly, the oil in the oil sump 86 is supplied to the suction passage 7
4. The oil is sucked into the suction chamber 70 through the hole 73 and the suction port 72, and the oil in the discharge chamber 71 is fed to the oil supply passage 52 through the discharge port 75, the hole 76, the discharge passage 77, and the hole 78.

[0024]

The above-mentioned conventional oil supply pump
In 60, when the protrusion 68 enters the slot 69 by the swing of the rotor 67 in the cavity 64, the oil in the chamber 80 limited by the tip surface of the protrusion 68 and the inner surface of the slot 69 is protruded. The escape escapes through the gap 81 between the side surface of the slot 68 and the side surface of the slot 69. However, since the gap 81 is narrow, the pressure of the oil in the chamber 80 becomes excessive and the power consumption of the oil supply pump 60 increases. .

Although oil is supplied from the oil supply passage 52 to the bearing gap 51 between the lower bearing 85 and the rotary shaft 5 through the oil hole 93, only oil leaking from the bearing gap 51 is supplied. However, there is a problem that it is difficult to sufficiently lubricate the bearing gap 51 of the lower bearing 85.

[0026]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and its gist is that the outer peripheral surface of a rotor housed in a cavity is formed inside the cavity. The suction chamber is limited to one side of the projection by inserting a projection, which is in line contact with the peripheral surface and protruding from the outer peripheral surface of the rotor, into a slot formed in the inner peripheral surface of the cavity. The discharge chamber is limited to the other side, and the rotor is driven by the eccentric shaft portion of the rotating shaft to swing in the cavity, thereby reciprocating the protrusion in the slot and simultaneously sucking oil into the suction chamber. The oil supply pump for discharging the oil in the discharge chamber, wherein an oil path for guiding the oil in the chamber limited by the tip end surface of the projection and the slot to the discharge chamber is provided.

Another feature is that the oil passage is formed by a groove formed in the end face of the projection on the discharge chamber side.

Still another feature is that the cavity is bored in a bearing that supports the rotating shaft, the discharge chamber communicates with an oil supply passage formed in the rotating shaft, and the oil passage is formed. Is connected to the oil supply passage via a bearing gap between the rotary shaft and the bearing.

[0029]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention is shown in FIG.
It is a partial cross-sectional view along an arrow. On the discharge chamber 71 side of the upper end surface of the rotor 67 and the projection 68, a groove 91 is formed from the tip of the projection 68 in the centripetal direction. A crescent-shaped notch 92 is formed on the outer periphery of the rotating shaft 5.

The notch 92 is preferably formed at a position where the notch 92 communicates with the groove 91 when the protrusion 68 enters the slot 69. Other configurations are the same as those of the conventional oil supply pump shown in FIG. 3, and corresponding members are denoted by the same reference numerals and description thereof is omitted.

When the rotary shaft 5 rotates, the rotor 67 swings in the cavity 64 while the outer peripheral surface thereof is in line contact with the inner peripheral surface of the cavity 64, and the projection 68 is thereby moved to the slot. Reciprocate in 69.

Then, the oil in the oil sump 86 flows into the suction passage 74 and the hole.
73, the oil is sucked into the suction chamber 70 through the suction port 72, and the oil in the discharge chamber 71 is pumped to the oil supply passage 52 through the discharge port 75, the hole 76, the discharge passage 77, and the hole 78.

When the protrusion 68 enters the slot 69 by the swing of the rotor 67 in the cavity 64, the notch 92
Communicate with 91. Thereby, the oil in the chamber 80 flows out to the discharge chamber 71 through the groove 91, and at the same time, a part of the oil enters the oil supply passage 52 through the notch 92 and the oil hole 93.

Therefore, since the pressure increase of the oil in the chamber 80 can be prevented, the power consumption of the oil supply pump 60 can be prevented from increasing. Further, since oil can be supplied from the notch 92 to the bearing gap 51, the bearing gap 51 can be sufficiently lubricated.

Instead of the groove 91, an oil passage for communicating the chamber 80 with the discharge chamber 71 may be formed inside the projection 68 and the rotor 67.

[0036]

According to the present invention, when the protrusion enters the slot due to the swinging of the rotor, the oil in the room limited by the tip end surface of the protrusion and the slot flows out to the discharge chamber through the oil passage. Therefore, it is possible to prevent the pressure of the oil in the chamber from abnormally increasing, thereby preventing an increase in power consumption of the oil supply pump.

If the oil passage is formed by a groove formed on the end face of the projection on the side of the discharge chamber, the oil passage can be formed easily and at low cost.

The cavity is bored in a bearing that supports the rotary shaft, the discharge chamber communicates with an oil supply passage formed in the rotary shaft, and the oil passage is connected to the oil supply passage through a bearing gap between the rotary shaft and the bearing. With the communication, the amount of oil supplied to the bearing gap between the rotating shaft and the bearing can be increased.

[Brief description of the drawings]

1A and 1B show an embodiment of the present invention, in which FIG. 1A is a longitudinal sectional view of a refueling pump, and FIG. 1B is a partial transverse sectional view taken along the line BB of FIG. 1A.

FIG. 2 is a longitudinal sectional view of a conventional hermetic scroll compressor.

FIG. 3 shows a conventional oil supply pump, (A) is a longitudinal sectional view,
(B) is a view along arrow B-B of (A), and (C) is a view of C-
It is an arrow view along arrow C.

[Explanation of symbols]

 60 oil pump 85 lower bearing 62 recess 63 thrust plate 64 cavity 65 cover 67 rotor 68 projection 69 slot 70 suction chamber 71 discharge chamber 5 rotary shaft 5a eccentric shaft 52 oil supply passage 77 discharge passage 79 relief valve 80 chamber 91 oil passage 51 Bearing clearance

Claims (3)

[Claims] 1. An outer peripheral surface of a rotor housed in a cavity is brought into line contact with an inner peripheral surface of the cavity, and a protrusion protruding from an outer peripheral surface of the rotor is formed on an inner peripheral surface of the cavity. The rotor is driven by the eccentric shaft portion of the rotating shaft to swing in the cavity by limiting the suction chamber to one side of the protrusion and the discharge chamber to the other side by fitting into the provided slot. In this way, the protrusion reciprocates in the slot and simultaneously sucks oil into the suction chamber and discharges the oil in the discharge chamber. The oil in the chamber limited by the tip end surface of the protrusion and the slot An oil passage for guiding the oil to the discharge chamber. 2. The oil supply pump according to claim 1, wherein the oil passage is formed by a groove formed in the end face of the projection on the discharge chamber side. 3. The cavity is bored in a bearing that supports the rotating shaft, the discharge chamber communicates with an oil supply passage bored in the rotating shaft, and the oil passage is connected to the rotating shaft and the bearing. The oil supply pump according to claim 1, wherein the oil supply passage communicates with the oil supply passage through the bearing gap.