JPH06299831A - Lubricating pump of two-cycle engine - Google Patents

Abstract

PURPOSE:To decrease the minimum supply oil amount by forming a plurality of communicating holes for communicating an oil pressure chamber with an introducing port or a discharge port, increasing the maximum supply oil amount through a process of discharging lubricating oil per each rotation of a valve body at plural times, intermittently rotating the valve body by the fixed angle, and lengthening the discharging interaval. CONSTITUTION:In an oil pump 2, a main step motor 12 is rotated by the fixed angle, thereby a valve main body 18 is turned through a driving cap 19 and a driving rod 20. When respective lateral holes 18b, 18c of the valve body 18 reache in the suction process position, the driving rod 20 is pushed up by the projecting part of a cam 17d, thereby the valve body 18 is raised, and the oil pressure chamber is evacuated, and lubricating oil is sucked into the oil pressure chamber. On the other hand, when respective lateral holes 18b, 18c reach the discharge process position, the driving rod 20 is positioned in the recessed part of the cam 17d, and the valve body 18 is lowered by energizing force of a discharge spring 21, and then lubricating oil is discharged. Moreover, a sub step motor 14 is rotated by the fixed angle, thereby a deviation 23 adjusts an adjusting rod 22, thereby the capacity of the oil pressure chamber is changed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lubrication pump for a two-cycle engine, and more specifically, it can expand the dynamic range, and when it is adopted in a multi-cylinder engine, the lubrication oil supply amount is optimized for each cylinder. The present invention relates to an improvement in a pump structure that allows variable control.

[0002]

2. Description of the Related Art Two-cycle engine lubrication methods include a mixed lubrication method that uses a mixed fuel and a separate oil supply method that directly supplies lubricating oil with a lubricating pump. A mechanical drive type plunger pump is generally used as the lubrication pump. This is because a distributor is rotatably arranged in a pump casing, a plunger is axially movable in the distributor, the distributor is rotationally driven by an engine output, and the plunger is arranged in the distributor. A cam formed on the end surface of the viewer is caused to make a stroke to suck the lubricating oil, and the plunger is pressed by a spring force to discharge the lubricating oil. Further, this conventional pump is equipped with an adjusting pulley that regulates the magnitude of the stroke of the plunger according to the engine operating state.

In a multi-cylinder engine, the required lubricating oil amount may vary from cylinder to cylinder, and the required lubricating amount also changes depending on the engine operating condition. As a conventional lubrication device that meets these demands, the discharge passage is branched into a plurality of parts on the way, a three-way solenoid valve is provided in each branch passage, and a return passage to an oil tank is provided to meet the requirements of each cylinder. There is a device provided with a control means for controlling the opening / closing of the solenoid valve according to the amount of lubricating oil.

[0004]

By the way, in this type of lubricating pump, it is required to control the amount of lubricating oil with a width as wide as possible according to the operating state of the engine, that is, to expand the dynamic range. The dynamic range of the conventional lubrication pump is determined by the cam height of the cylindrical cam and the stroke control width, but these values are naturally limited, and therefore the dynamic range of the conventional pump cannot be increased so much.

Further, in the above-mentioned conventional lubrication apparatus, in order to control the oil amount for each cylinder, an electromagnetic valve, a return passage, etc. are required for each cylinder, resulting in high cost and a large arrangement space. There is a problem.

The present invention has been made in view of the above conventional problems, and an object of the present invention is to provide a lubrication pump for a two-cycle engine capable of expanding a dynamic range and controlling an optimum oil amount for each cylinder. .

[0007]

According to a first aspect of the present invention, a casing having a valve hole communicating with an inlet port and a discharge port for lubricating oil and a rotatably and axially movable insertable member are inserted into the valve hole. Valve body, a hydraulic chamber that generates hydraulic pressure by axial movement of the valve body, a plurality of communication holes that communicate the hydraulic chamber with the introduction port or the discharge port depending on the angular position of the valve body, and the valve. A lubrication pump for a two-cycle engine, comprising: a rotation driving means for intermittently rotating and driving a body by a predetermined angle; and an axial direction driving means for axially moving the valve body.

The invention of claim 2 is characterized in that a plurality of the discharge ports are formed and the number of the communication holes is one, and the invention of claim 3 is that the valve body faces the valve body in the valve hole. In this manner, the adjusting rod which is inserted so as to be movable in the axial direction and forms the bottom surface of the hydraulic chamber, and the capacity control means for variably controlling the axial position of the rod are featured.

[0009]

According to the lubricating oil pump of the first aspect of the invention,
Since a plurality of communication holes that connect the hydraulic chamber and the inlet or the discharge port are formed, the valve is discharged a plurality of times for each rotation of the valve body, and therefore the maximum amount of oil supply can be increased accordingly. Further, according to the present invention, the rotary drive means for intermittently rotating the valve body by a predetermined angle is provided. Therefore, the minimum oil supply amount can be made extremely small by extending the discharge interval, and as a result, the dynamic range can be expanded. .

According to the lubricating oil pump of the second aspect of the invention, since the casing has a plurality of discharge ports, the lubricating oil is discharged from a plurality of positions per one rotation of the valve body. Therefore, by connecting each discharge port to the lubricating oil supply section of each cylinder,
Lubricating oil can be supplied to each cylinder individually, and the structure is extremely simple as compared with the conventional one provided with a three-way port solenoid valve and the like.

According to the third aspect of the present invention, the adjusting rod is inserted into the valve hole, the rod, the valve body, and the inner surface of the valve hole form a hydraulic chamber, and the rod moves forward and backward to change the volume of the hydraulic chamber. Therefore, the optimum oil amount can be supplied to each cylinder by advancing and retracting the rod according to the required oil amount of each cylinder.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 are views for explaining an oil pump of a two-cycle engine according to an embodiment (first embodiment) of the invention of claims 1 and 3, and FIG. 1 adopts the oil pump of the embodiment. FIG. 2 is an overall configuration diagram of the lubricating device, FIG. 2 is a sectional plan view of the oil pump, and FIG. 3 is a sectional front view of the oil pump.

In these drawings, reference numeral 1 denotes a two-cycle engine lubricating device for supplying lubricating oil to the intake passage 8 downstream of the carburetor. In this lubrication apparatus 1, an inlet 3 of an oil pump 2 is connected to an oil tank 5 via an introduction hose 4, and a discharge port 6 is connected to a downstream side of a carburetor in an intake passage 8 via a discharge hose 7. It is configured. Reference numeral 9 is a control device that controls the rotation and capacity of the oil pump 2.

The oil pump 2 has a pump case 10
A valve mechanism 11 is accommodated and arranged therein, a main step motor 12 for rotation control that rotationally drives the valve mechanism 11 is attached to an upper portion of the pump case 10, and a capacity control mechanism 13 is provided on a bottom wall portion of the pump case 10. Provided, the pump case 10
The sub-step motor 14 for driving the capacity control mechanism 13 is attached to the side wall of the sub-step.

The pump case 10 has a structure in which an upper end opening of a bottomed cylindrical lower case 15 is closed by a lid case 16. The lower case 15 has an inlet port 3 and a discharge port 6 of 90 degrees. It is formed so as to form an angular interval. The main step motor 12 is fixed to the lid case 16, and the drive shaft 12 a of the motor 12 projects into the pump case 10.

The pump mechanism 11 includes the lower case 1
5, a valve case (corresponding to the casing of the present invention) 17 fixed and arranged, and a valve body inserted into a valve hole 17a formed at the axial center of the valve case 17 so as to be rotatable and axially movable. 18 and a drive cap 19 that rotationally drives the valve element 18.

The valve case 17 is disk-shaped, and the introduction hole 17b and the discharge hole 17b for communicating the introduction port 3 and the discharge port 6 with the valve hole 17a are formed at an angular interval of 90 degrees. There is. In addition, 17c is the above-mentioned introduction hole 1
7b is a communication hole that communicates with the inside of the pump case 10.
A cam 17d is formed in a ring shape on the upper surface of the valve case 17.

A drive rod 20 is inserted and fixed to the upper end of the valve element 18 in a direction perpendicular to the axis, and the drive rod 20 is in sliding contact with the cam 17d of the valve case 17.
The outwardly projecting end of the drive rod 20 is locked in a locking groove 19a formed in the drive cap 19,
A discharge spring 21 for urging the drive rod 20 downward in the drawing is provided between the center recess 19b of the cap 19 and the drive rod 20. Furthermore, the output shaft 12a of the main step motor 12 is inserted and fixed to the drive cap 19. As a result, the valve body 18 is
It is driven to rotate by the step motor 12, and the cam 17d,
And is driven in the axial direction by the discharge spring 21. Therefore, the step motor 12 serves as a rotation driving means, and the cam 17d and the discharge spring 21 serve as an axial driving means.

An adjusting rod 22 forming a part of the displacement control mechanism 13 is inserted in the lower portion of the valve hole 17a so as to be movable in the axial direction, and the upper end surface of the rod 22 and the inner surface of the valve hole 17a. , And the space surrounded by the lower end surface of the valve body 18 is a hydraulic chamber. Further, the valve body 18 includes
A communication hole is formed by a vertical hole 18a communicating with the hydraulic chamber and lateral holes 18b, 18c orthogonal to the vertical hole 18a. The lateral holes 18b and 18c communicate with the introduction hole 17b or the discharge hole 17c depending on the angular position of the valve body 18.

The capacity control mechanism 13 includes the adjusting rod 22, an eccentric cam 23 that changes the axial position of the rod 22 to change the volume of the hydraulic chamber, and urges the adjusting rod 22 downward in the drawing. And a return spring 24. The eccentric cam 23 is pivotally supported by a support shaft 25 inserted and fixed near the lower end of the lower case 15. The eccentric cam 23 is used for the output shaft 14 of the sub-step motor 14.
It is fixed to the drive rod 26 that is rotationally driven by a.
The sub-step motor 14 and the capacity control mechanism 13 constitute a capacity control means. Reference numeral 27 is a cap that closes the lower opening of the capacity control mechanism 13.

Next, the function and effect of the apparatus of this embodiment will be described. In the apparatus 1 of the present embodiment, the main step motor 12 rotates by 45 degrees at intervals according to the engine operating state, whereby the valve body 18 is rotationally driven via the drive cap 19 and the drive rod 20.

When any of the lateral holes 18b and 18c of the valve body 18 reaches the suction stroke position shown in the drawing, the drive rod 20 is moved.
Are pushed up by the convex portion of the cam 17d, so that the valve body 18 rises and the hydraulic chamber becomes negative pressure, and the lubricating oil is sucked into the hydraulic chamber. When any of the lateral holes 18b and 18c reaches the illustrated discharge stroke position, the drive rod 20
Is located in the concave portion of the cam 17d, and the valve body 18 is the discharge spring 21.
Is lowered by the urging force of and the lubricating oil is discharged.

Further, the sub-step motor 14 rotates to an angular position corresponding to the required discharge amount per time, whereby the eccentric cam 23 adjusts the vertical position of the adjusting rod 22, and as a result, the volume of the hydraulic chamber increases. The discharge amount changes and the discharge amount per time is controlled to the above required value.

In the pump 2 of this embodiment, when the discharge amount is increased, the adjusting rod 22 is lowered to expand the volume of the hydraulic chamber or increase the rotational speed of the valve body 18. Of course, if the volume is increased and the speed is increased at the same time, the discharge amount can be further increased. Although there is a limit to the above-mentioned volume expansion and speed increase, in the present embodiment, the lubricating oil is discharged twice while the valve body 18 makes one rotation. Can increase.

On the other hand, in order to reduce the discharge amount, the adjusting rod 22 may be raised to reduce the volume of the hydraulic pressure generating chamber or the rotational speed of the valve body 18 may be slowed down. Of course, both operations are simultaneously performed. Is also good. In this case, since the main step motor 12 is employed in this embodiment, the rotational speed can be freely reduced, and the amount of oil supply can be made extremely small at this point.

As described above, in this embodiment, the maximum lubricating oil supply amount can be greatly increased and the minimum lubricating oil supply amount can be made minute, so that the so-called dynamic range can be expanded.

In the above embodiment, the case where the two lateral holes 18b and 18c as the communication holes are formed at intervals of 180 degrees has been described, but the number is not limited to two, and for example, at intervals of 120 degrees. It is also possible to form three of them, and in such a case, it is possible to discharge three times per one rotation of the valve body, so that the dynamic range can be further expanded.

FIGS. 4 and 5 are views for explaining a lubricating device according to one embodiment (second embodiment) of the invention of claims 2 and 3, and the same reference numerals as those in FIGS. 1 and 2 are the same. Or, shows a considerable portion. The second embodiment is an example in which the lubricating oil is discharged from two discharge ports per one rotation of the valve body 18.

In this embodiment, the introduction hole 17 of the valve case 17 is used.
Introducing hole 17b 'and communication port 17 at a position facing b
d'is formed. The lubricating oil from the oil tank is introduced from the communication hole 17d into the communication hole 17d 'through the upper space of the pump case 10. Further, the discharge hole 17c is provided at a position facing the discharge hole 17c and the discharge port 6b.
c'and the discharge port 6'are formed. On the other hand, the lateral hole forming the communication hole of the valve body 18 is formed only at 18b.
Although not shown, the pump of this embodiment is also provided with the displacement control mechanism 13 and the sub-step motor 14.

The discharge port 6 is connected to a front cylinder intake passage 8 of, for example, a V-type horizontal engine by a discharge hose 7, and the discharge port 6'is a discharge hose 7 '.
Is connected to the rear cylinder intake passage 8 '.

In the pump of this embodiment, as the valve element 18 rotates, the lubricating oil sucked in the suction stroke is discharged from the discharge port 6 in the discharge stroke and supplied to the front cylinder intake passage 8. On the other hand, the lubricating oil sucked in the suction stroke is discharged from the discharge port 6'in the discharge stroke and supplied to the rear cylinder intake passage 8 '.

Here, in a V-type engine, the required lubricating oil amount may differ between the front cylinder and the rear cylinder. For example, the rear side cylinder has a large heat load because the cooling air is less likely to hit the front side cylinder, and therefore the required lubricating oil amount of the rear side cylinder may be larger than that of the front side cylinder. The capacity control means is activated. This is realized by the step motor 14 changing the angular position of the eccentric cam 23 so that the hydraulic chamber volume in the suction stroke becomes larger than the volume in the suction stroke.

In the second embodiment, the case where there are two ejection ports has been described. However, the number is not limited to two, and three ejection ports may be provided at intervals of 120 degrees, for example. In this way, the three cylinders can be refueled individually.

Further, in the above embodiment, the lateral holes 18b and 18c as the communication holes are formed in the valve body 18 itself, but this may be constructed as shown in FIG. In the figure, the same reference numerals as those in FIG. 3 indicate the same or corresponding parts. The valve body of this embodiment has a valve hole 1
7a, a valve cylinder 26 rotatably and immovably arranged in the axial direction, a valve rod 27 rotatably and axially movably arranged in the valve cylinder 26, and so as to face the valve rod 27. It is composed of a plug 29 inserted in the valve cylinder 26,
The space enclosed by these members 26, 27, 29 is a hydraulic pressure generating chamber a. The communication hole 2 is connected to the valve cylinder 26.
6a is formed. In addition, 31 and 32 are valve cylinders 26,
A spring for urging the valve rod 27 downward, and 26b is an insertion hole for the drive shaft 20. Further, 42b and 42a are discharge position detecting springs and terminals.

Further, in each of the above embodiments, the lubricating oil is supplied to the intake passage, but the lubricating oil pump of the present invention can of course be adopted when directly supplying oil to the lubricated portion.

[0036]

According to the lubricating oil pump of the first aspect of the present invention, the number of communication holes is made to be plural so as to discharge a plurality of times per one rotation, so that the maximum supply amount of the lubricating oil can be increased accordingly. Since the rotation driving means for intermittently rotating the valve body by a predetermined angle is provided, the minimum oil supply amount can be made extremely small by increasing the discharge interval, and as a result, the dynamic range can be expanded.

According to the lubricating oil pump of the second aspect of the present invention, the lubricating oil is discharged from a plurality of positions per one rotation of the valve body by providing a plurality of discharging ports. By connecting to the supply unit, lubricating oil can be supplied to each cylinder individually, and there is an effect that the structure can be extremely simplified as compared with the conventional one provided with a three-way solenoid valve or the like.

According to the third aspect of the present invention, the adjusting rod inserted into the valve hole, the valve body and the inner surface of the valve hole form a hydraulic chamber.
Since the hydraulic chamber volume is made variable by advancing and retracting the adjusting rod, there is an effect that an optimal amount of lubricating oil can be supplied to each cylinder by advancing and retracting the rod according to the required lubricating oil amount of each cylinder.

[0039]

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of a lubricating device including an oil pump according to a first embodiment of the present invention.

FIG. 2 is a sectional plan view of the oil pump of the first embodiment.

FIG. 3 is a sectional side view of the first embodiment oil pump.

FIG. 4 is a cross-sectional plan view of an oil pump of a second embodiment according to the second and third aspects of the invention.

FIG. 5 is an overall configuration diagram of a lubricating device including the oil pump of the second embodiment.

FIG. 6 is a cross-sectional side view for explaining a modified example of the valve body.

[Explanation of symbols]

3 introduction port 6,6 'discharge port 12 main step motor (rotational drive means) 13,14 capacity control mechanism, sub-step motor (capacity control means) 17 valve case (casing) 17a valve hole 17d, 21 cam, discharge spring ( Axial direction drive means) 18 valve bodies 18b, 18c lateral holes (communication holes) 22 adjusting rods 26, 27 valve cylinders, valve rods (valve bodies)

Claims (3)

[Claims] 1. A casing having a valve hole communicating with the lubricating oil inlet and outlet, a valve element inserted into the valve hole so as to be rotatable and axially movable, and an axial direction of the valve element. A hydraulic chamber that generates hydraulic pressure by movement, a plurality of communication holes that communicate the hydraulic chamber with the introduction port or the discharge port depending on the angular position of the valve body, and intermittently rotate the valve body by a predetermined angle. A lubrication pump for a two-cycle engine, comprising: a rotary drive means; and an axial drive means for moving the valve element in an axial direction. 2. A casing having a valve hole communicating with an inlet port for lubricating oil and a plurality of discharge ports, a valve element inserted into the valve hole so as to be rotatable and axially movable, and a valve element of the valve element. A hydraulic chamber that generates hydraulic pressure by axial movement, a communication hole that communicates the hydraulic chamber with the introduction port or any of the discharge ports depending on the angular position of the valve element, and the valve element intermittently at a predetermined angle. A lubrication pump for a two-cycle engine, comprising: a rotary drive means for rotationally driving; and an axial drive means for axially moving the valve body. 3. The adjusting rod according to claim 1 or 2, which is inserted into the valve hole so as to face the valve body and is movable in the axial direction, and which forms a bottom surface of the hydraulic chamber, and a shaft of the rod. A lubrication pump for a two-cycle engine, comprising: a displacement control means for variably controlling a directional position.