JP2011231772A - Oil pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an oil pump capable of minimizing or preventing mixing of air into force-fed lubricating oil, and adapted to implement simplification, cost reduction, and the like of a structure by eliminating parts such as an oil tank, piping, or the like.SOLUTION: The oil pump has a pump stroke carrying out suction and force feeding of the lubricating oil, and the pump stroke includes a suction stroke sucking in the lubricating oil, a compression stroke compressing the lubricating oil mixed with air sucked in by the suction stroke, a discharge stroke discharging one part of the lubricating oil mixed with air in a state compressed by the compression stroke, and a delivery stroke delivering the lubricating oil remaining after the discharge stroke. Thereby, the lubricating oil removed as much as possible of the mixed air can be force-fed to a desired lubricating area while achieving simplification of the structure.

Description

  The present invention relates to an oil pump that sucks and pumps lubricating oil (oil), such as an internal combustion engine (engine), and more particularly, to an oil pump that is applied to a dry sump type engine that does not have an oil pan below the engine.

  A dry sump type that does not have an oil pan at the bottom of the engine because the road clearance can be increased in off-road motorcycles, etc., and in racing vehicles, the friction can be reduced and the overall height of the vehicle can be reduced by keeping the engine height low. The engine is adopted.

In this engine lubrication system, for example, as shown in FIG. 11, the lubricating oil accumulated in the lower crankcase (receptacle) 1 a of the engine 1 is sucked by the transfer oil pump 3 through the oil strainer 2 and is The air once stored in the external oil tank 5 via the attached piping 4 is separated.
The lubricating oil stored in the oil tank 5 is sucked by the lubricating oil pump 7 via the external pipe 6 and is pumped to the main gallery via the check valve 8 and the oil filter 9. Then, it is supplied from the crank journal or cylinder head to the camshaft journal, rocker arm, etc., and finally falls by its own weight and accumulates in the lower crankcase 1a.

  By the way, in the dry sump type lubrication system, in addition to the oil pump 7 for lubrication, an oil pump 3 for conveyance, an external oil tank 5 and pipes 4 and 6 are required. Further, when not used for a long time, it is necessary to add a check valve 8 or the like to prevent the lubricating oil from dropping from the oil tank 5. Therefore, a space for arranging these parts is required, and the cost is increased.

JP-A-9-203308 The microfilm of Japanese Utility Model Application No. 2-1077738 JP-A-6-167278

  The present invention has been made in view of the above circumstances. The object of the present invention is to suppress or prevent air from being mixed into the lubricating oil to be pumped as much as possible, and to provide components such as an oil tank and piping. An object of the present invention is to provide an oil pump that can be eliminated to simplify the structure and reduce costs.

The oil pump of the present invention is an oil pump having a pump stroke for sucking and pumping lubricating oil, and the pump stroke includes a suction stroke for sucking lubricating oil, and lubrication of air mixture sucked by the suction stroke. A compression stroke for compressing the oil, a discharge stroke for discharging a part of the aerated lubricating oil compressed by the compression stroke, and a discharge stroke for discharging the remaining lubricating oil after the discharge stroke. It is a feature.
According to this configuration, in the case of a dry sump type engine or the like, the lubricating oil collected in the lower part of the crankcase is first sucked up by the intake stroke through the oil strainer, and then the air-mixed lubrication sucked in by the intake stroke is performed. The oil is compressed by the compression stroke, and then a part of the air-mixed lubricating oil is discharged by the discharge stroke. Subsequently, the lubricating oil remaining after the discharge stroke is discharged by the discharge stroke, and various lubrication regions are obtained. It is pumped towards. In this way, by providing a discharge stroke between the compression stroke and the discharge stroke, it is possible to efficiently remove the mixed-in air using only an oil pump for pumping without using an external oil tank or the like. it can.

In the above-described configuration, the casing, the outer rotor that is rotatably disposed in the casing, and the inner that is rotatably disposed inside the outer rotor so as to suck and pump the lubricating oil in cooperation with the outer rotor. The casing includes a rotor and includes a suction port for sucking lubricating oil during a suction stroke, a discharge port for discharging a part of aerated lubricating oil that is compressed during a discharge stroke, and a discharge stroke. In this case, a configuration including a discharge port for discharging the remaining lubricating oil can be employed.
According to this configuration, when the lubricating oil is sucked from the suction port and subsequently compressed, a part of the mixed air-containing lubricating oil is discharged from the discharge port, and the remaining lubricating oil is discharged from the discharge port. Pumped toward various lubrication areas. In this way, simply using a trochoidal oil pump consisting of a casing, an outer rotor, and an inner rotor that define the suction port, discharge port, and discharge port, the structure can be simplified and mixed air can be efficiently used. The oil can be pumped to various lubrication regions with good exclusion.

In the above configuration, the casing can include a suction passage that communicates with the suction port, a discharge passage that communicates with the discharge port, and a discharge passage that communicates with the discharge port.
According to this configuration, since a suction passage, a discharge passage, and a discharge passage are also formed in the casing, members for these passages are unnecessary, the number of parts is reduced, and the structure is simplified. Can be achieved.

In the above-described configuration, it is possible to adopt a configuration in which the discharge port and the discharge passage are formed at a predetermined distance above the discharge port and the discharge passage in the vertical direction.
According to this configuration, mixed air can be efficiently removed.

In the above configuration, a configuration is adopted in which the suction port and the suction passage, the discharge port and the discharge passage, and the discharge port and the discharge passage are formed on one side of the outer rotor and the inner rotor. Can do.
According to this configuration, the oil pump itself can be thinned, and a structure with good assemblability can be obtained.

  According to the oil pump configured as described above, before discharging the lubricating oil by the discharge stroke, a part of the aerated lubricating oil sucked by the suction stroke and compressed by the compression stroke is discharged by the discharge stroke. Because the remaining lubricating oil from which most of the air has been discharged is discharged during the discharge stroke, the air mixed into the lubricating oil is separated without using an external oil tank, especially in dry sump engines. Thus, lubricating oil can be pumped to various lubricating areas, that is, mixing of air into the pumped lubricating oil can be suppressed or prevented as much as possible, and parts such as oil tanks and pipes can be eliminated, An oil pump that can achieve simplification and cost reduction can be provided.

It is a block diagram which shows the lubrication system provided with the oil pump of this invention. 1 shows an embodiment of an oil pump according to the present invention, in which (a) is a plan view and (b) is a side sectional view. (A), (b), (c), (d), (e) is an operation | movement diagram for demonstrating operation | movement of the oil pump shown in FIG. The other embodiment of the oil pump which concerns on this invention is shown, (a) is a top view, (b) is a sectional side view. (A), (b), (c), (d), (e) is an operation | movement diagram for demonstrating operation | movement of the oil pump shown in FIG. It is a top view which shows other embodiment of the oil pump which concerns on this invention. It is a right view of the oil pump shown in FIG. It is a left view of the oil pump shown in FIG. (A), (b), (c), (d), (e), (f) is an operation | movement diagram for demonstrating operation | movement of the oil pump shown in FIG. 6 thru | or FIG. It is a block diagram which shows one Embodiment of the lubrication apparatus provided with the oil pump which concerns on this invention. It is a block diagram which shows the conventional lubrication system.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a block diagram showing a lubrication system incorporating an oil pump according to the present invention, and FIGS. 2A, 2B and 3 are cross-sectional views for explaining the schematic configuration and operation of the oil pump. It is. This lubrication system does not have an external oil tank and pipe as in the prior art, and only the oil pump 10 of the present invention is connected between the oil strainer 2 and the oil filter 9.

As shown in FIGS. 2A and 2B, the oil pump 10 includes a casing 11, an outer rotor 12 that is rotatably supported in the casing 11, and a rotatably supported inside the outer rotor 12. The inner rotor 13 is provided.
The inner rotor 13 has four protrusions, is directly connected to the drive shaft 14, and is supported so as to be rotatable around the axis C1. The outer rotor 12 has five recesses with which the protrusions of the inner rotor 13 are engaged, and is slidably fitted to the cylindrical surface 11a of the casing 11 and supported rotatably about the axis C2. That is, the oil pump 10 is a four-leaf, five-node trochoid pump.

  The casing 11 includes a substantially crescent-shaped suction port 11b and a suction passage 11b 'for sucking the lubricating oil on one side surface 13a and 12a side of the inner rotor 13 and the outer rotor 12, and a compressed lubricating oil. A discharge port 11d and a discharge passage 11d 'are provided for positively discharging mixed air, that is, air-mixed lubricating oil, while the other side surfaces 13b and 12b of the inner rotor 13 and outer rotor 12 are provided. Are provided with a discharge port 11c and a discharge passage 11c ', each of which has a substantially crescent-shaped upper portion for discharging compressed lubricating oil.

  Here, as shown in FIG. 2B, the discharge port 11d is provided above the discharge port 11c in the vertical direction, and the lower end portion 11d '' of the discharge port 11d and the upper end of the discharge port 11c. The part 11c ″ is at the same height in the vertical direction and is flush. Thereby, the opening area which combined the discharge port 11d and the discharge port 11c can be enlarged as much as possible, and both opening ratios can be set suitably as needed.

Next, the operation of the oil pump 10 will be described with reference to FIG. In FIG. 3, the stroke consisting of suction and compression of lubricating oil mixed with air, discharge of air and part of the lubricating oil, and discharge of the lubricating oil is shown in one pump chamber. The filled area is indicated by hatching.
First, when the inner rotor 13 and the outer rotor 12 are rotated clockwise, as shown in FIG. 3A, the lubricating oil starts to be sucked from the suction port 11b, and further rotated, as shown in FIG. 3B. Inhale further lubricating oil.

Then, as shown in FIG. 3 (c), from the state in which the lubricating oil has been sucked in to the maximum, the compression stroke is subsequently entered, and as shown in FIG. First, a part of the mixed air and lubricating oil is discharged from the discharge port 11d through the passage 11d ′.
Further, when the inner rotor 13 and the outer rotor 12 rotate clockwise, the discharge port 11d is closed, and the remaining lubricating oil is discharged from the discharge port 11c as shown in FIG. Pumped towards the area.

Here, the maximum volume of the lubricating oil discharged from the discharge port 11c is an area of the lubricating oil S compressed in the previous stroke, as shown in FIG.
Actually, due to the cooperative action of the inner rotor 13 and the outer rotor 12, the four pump chambers are continuously connected to suck and compress the lubricating oil mixed with air, discharge the air and some of the lubricating oil, and lubricate. The oil is discharged.

4 and 5 show another embodiment of the oil pump according to the present invention. As shown in FIG. 4, the oil pump 20 includes a casing 21, an outer rotor 22 that is rotatably supported in the casing 21, and an inner rotor similar to that described above that is rotatably supported inside the outer rotor 22. 13 is a trochoid pump.
The outer rotor 22 has five recesses with which the protrusions of the inner rotor 13 are engaged, and is slidably fitted to the cylindrical surface 21a of the casing 21, and opens at the outer peripheral surface of the five recess portions. There are five discharge ports 22d.

  As shown in FIGS. 4A and 4B, the casing 21 has a substantially crescent-shaped suction port 21b for sucking lubricating oil on one side surface 13a, 22a side of the inner rotor 13 and the outer rotor 22, and A suction passage 21b ', a discharge port 21c having a substantially crescent-shaped upper portion for discharging compressed lubricating oil, and a discharge passage 21c' are provided. A discharge passage 21d ′ that can communicate with the discharge port 22d is provided so as to positively discharge the air mixed in the compressed lubricating oil, that is, the air-containing lubricating oil, upward from a part of the surface 21a. Yes.

  Here, as shown in FIGS. 4A and 4B, the discharge port 22d and the passage 21d 'are provided above the discharge port 21c in the vertical direction, and the direction of the discharge port 21c and the direction of the discharge port 22d. The air separation is more efficient. Further, since the suction port 21b, the passage 21b ', the discharge port 21c, and the passage 21c' are provided only on the side surfaces 13a and 22a of the inner rotor 13 and the outer rotor 22, the oil pump 20 itself can be thinned. The

Next, the operation of the oil pump 20 will be described with reference to FIG. In FIG. 5, a process including suction and compression of lubricating oil mixed with air, discharge of air and a part of the lubricating oil, and discharge of the lubricating oil is shown in one pump chamber. The filled area is indicated by hatching.
First, as the inner rotor 13 and the outer rotor 22 rotate clockwise, as shown in FIG. 5 (a), the lubricating oil begins to be sucked from the suction port 21b, and further rotated, as shown in FIG. 5 (b). Inhale more lubricant as shown.

Then, as shown in FIG. 5 (c), the compression stroke is started from the state in which the lubricating oil is sucked in the maximum, and first, as shown in FIG. ′ Begins to communicate, and part of the mixed air and lubricating oil is discharged from the discharge port 22d through the passage 21d ′.
Further, when the inner rotor 13 and the outer rotor 22 are rotated clockwise, as shown in FIG. 5E, the remaining lubricating oil is discharged from the discharge port 21c, pumped toward various lubricating regions, and discharged. The outlet 22d is closed by the cylindrical surface 21a. In practice, the four pump chambers are continuously connected by the cooperative action of the inner rotor 13 and the outer rotor 22 to suck and compress the lubricating oil mixed with air, and discharge the air and some of the lubricating oil. The discharging operation of the lubricating oil is performed.

6 to 9 show still another embodiment of the oil pump according to the present invention. This oil pump 30 is a trochoid pump having a casing 31 and an outer rotor 12 and an inner rotor 13 similar to those described above that are rotatably supported in the casing 31.
As shown in FIGS. 6 to 8, the casing 31 includes a substantially crescent-shaped suction port 31 b for sucking lubricating oil and a suction passage on the side surfaces 13 a and 12 a of the inner rotor 13 and the outer rotor 12. 31b ', a substantially fan-shaped discharge port 31c for discharging compressed lubricant and a discharge passage 31c', and air mixed in the compressed lubricant oil above the discharge port 31c in the vertical direction, that is, air A substantially fan-shaped discharge port 31d and a discharge passage 31d 'are provided for positively discharging the mixed lubricating oil.

  Here, as shown in FIG. 6, the discharge port 31d and the passage 31d ′ are provided above the discharge port 31c in the vertical direction and are separated from each other by a predetermined distance, so that air separation is more efficient. Done. Further, since the suction port 31b, the passage 31b ', the discharge port 31c, the passage 31c', the discharge port 31d, and the passage 31d 'are provided only on the side surfaces 13a and 12a of the inner rotor 13 and the outer rotor 12, the oil pump The width of 30 itself can be reduced.

Next, the operation of the oil pump 30 will be described with reference to FIG. In FIG. 9, the stroke consisting of suction and compression of lubricating oil mixed with air, discharge of air and a part of the lubricating oil, and discharge of the lubricating oil is shown in one pump chamber. The filled area is indicated by hatching.
First, the inner rotor 13 and the outer rotor 12 rotate clockwise to suck the lubricating oil from the suction port 31b, and when the lubricating oil is sucked to the maximum as shown in FIG. In the stroke, as shown in FIG. 9B, first, the pump chamber starts to communicate with the discharge port 31d. From this state, the air and a part of the lubricating oil that have passed through the state shown in FIG. 9 (c) until the discharge port 31d is closed as shown in FIG. 9 (d) are discharged. It is discharged from the outlet 31d through the passage 31d '.

Further, when the inner rotor 13 and the outer rotor 12 rotate clockwise, as shown in FIG. 9E, the remaining lubricating oil begins to be discharged from the discharge port 31c while being further compressed, as shown in FIG. 9F. Thus, the lubricating oil is completely discharged and pumped toward various lubricating regions, and then the discharge port 31c is closed.
Actually, the four pump chambers are continuously connected by the cooperative action of the inner rotor 13 and the outer rotor 12 to suck and compress the lubricating oil mixed with air, and discharge the air and some of the lubricating oil. The discharging operation of the lubricating oil is performed.

  FIG. 10 is a block diagram showing an embodiment of a lubrication apparatus provided with an oil pump according to the present invention. This lubricating device includes an oil strainer 40 that is disposed in the crankcase lower portion 1a and has a suction port for sucking lubricating oil, and an oil pump 10 that is disposed on the downstream side of the oil strainer 40 and on the upstream side of the oil filter 9 as described above. And an air discharge port 71 disposed in a passage 60 between the oil strainer 40 and the oil pump 10.

  The oil pump 10 includes the same inner rotor 13 and outer rotor 12, and a casing 11 having a suction port 11b and a passage 11b ', a discharge port 11c and a passage 11c', and a discharge port 11d and a passage 11d '. Yes. Here, the suction port 11b and the passage 11b 'are arranged so as to be positioned below the oil level of the lubricating oil accumulated in the crankcase lower portion 1a.

  In this lubricating device, when lubricating oil is sucked from the oil strainer 40, it passes through the passage 60 and reaches the region of the air chamber 70. Here, the air mixed in the lubricating oil is separated into an upper space of the air chamber 70 and is discharged from the air discharge port 71 into the crankcase. Subsequently, the lubricating oil from which at least a part of the air has been separated is sucked from the suction port 11b of the oil pump 10 and sucked into the pump chamber, and then compressed, and the mixed air and a part of the lubricating oil are discharged. The gas is discharged from the outlet 11d through the passage 11d 'into the crankcase. Subsequently, the lubricating oil from which air has been removed as much as possible is discharged from the discharge port 11c and pumped toward various lubricating regions.

In this embodiment, the oil pump 10 shown in FIG. 2 is adopted, but the other oil pumps 20 and 30 shown in the other embodiments described above may be adopted.
In the above-described embodiment, the trochoid pumps 10, 20, and 30 are shown as the oil pump. However, the oil pump is not limited to this, and in an internal gear type oil pump or an external gear type oil pump, It is also possible to employ a configuration provided with an air outlet.

  As described above, according to the oil pump of the present invention, it is possible to suppress or prevent air from being mixed into the lubricating oil to be pumped as much as possible, and to simplify the structure by removing components such as the oil tank and piping. Since it can achieve low cost, it can be applied to dry sump engines mounted on racing vehicles such as off-road motorcycles, as well as other engines or other mechanisms that require pumping of lubricating oil Is also useful.

DESCRIPTION OF SYMBOLS 1 Engine 1a Crankcase lower part 2 Oil strainer 9 Oil filter 10, 20, 30 Oil pump 11, 21, 31 Casing 11a, 21a Cylindrical surface 11b, 21b, 31b Inlet 11b ', 21b', 31b 'Intake passage 11c , 21c, 31c Discharge ports 11c ', 21c', 31c 'Discharge passages 11d, 22d, 31d Discharge ports 11d', 21d ', 31d' Discharge passages 12, 22 Outer rotor 13 Inner rotors 12a, 13a, 22a One side surface 12b, 13b Other side surface 14 Drive shaft 40 Oil strainer 60 Passage 70 Air chamber 71 Air discharge port

Claims (5)

An oil pump having a pump stroke for sucking and pumping lubricating oil,
The pump stroke includes one of a suction stroke for sucking lubricating oil, a compression stroke for compressing the air-mixed lubricating oil sucked in the suction stroke, and an air-mixed lubricating oil in a state compressed by the compression stroke. A discharge stroke for discharging the part, and a discharge stroke for discharging the remaining lubricating oil after the discharge stroke,
An oil pump characterized by that. A casing,
An outer rotor disposed rotatably in the casing;
An inner rotor rotatably disposed inside the outer rotor to suck and pump lubricant oil in cooperation with the outer rotor,
The casing includes a suction port for sucking lubricating oil during the suction stroke, a discharge port for discharging a part of the aerated lubricating oil that is compressed during the discharge stroke, and a discharge port for the discharge stroke. Including a discharge port for discharging the remaining lubricating oil when
The oil pump according to claim 1. The casing includes a suction passage that communicates with the suction port, a discharge passage that communicates with the discharge port, and a discharge passage that communicates with the discharge port.
The oil pump according to claim 2. The discharge port and the discharge passage are formed at a predetermined distance above the discharge port and the discharge passage in the vertical direction.
The oil pump according to claim 3. The suction port and the suction passage, the discharge port and the discharge passage, and the discharge port and the discharge passage are formed on one side of the outer rotor and the inner rotor.
The oil pump according to claim 3 or 4, characterized in that.

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