JPS601383A - Plunger pump for oil - Google Patents

Abstract

PURPOSE:To surely suck and discharge a minute quantity of oil even if air invades into a cylinder, by providing the circumferential side of the cylinder with an auxiliary discharge port and fitting the port with a check valve whose opening pressure is lower than that of a check valve for a discharge port. CONSTITUTION:The forced-in volume, which is determined by the force-in stroke H2 of a plunger 33 after the closure of the auxiliary discharge port 41 of an oil pump 25, is set at a prescribed minute value so that at least the prescribed volume of oil is surely sucked by moving the plunger 33 back from the opened position of the auxiliary discharge port 41, as shown in Figs A and B, even if air invades into a cylinder 34. As shown in Figs C and D, excess oil is discharged through the port 41 by pushing the plunger 33 in. After that, the minute quantity of oil is obtained from a main discharge port by pushing the plunger 33 into the extreme forward movement position, as shown in Fig. E.

Description

[Detailed description of the invention] The present invention relates to a sylanger type oil pump.

In the separation lag device used in 2-stroke internal combustion engines such as C'4 rlA, a silanizer type oil pump is installed in an oil tank separate from the fuel tank.

This plunger type oil pump and the like make it possible to supply vortex oil to each part of the engine. In the above-mentioned syringe type oil pump, the plunger is housed in a reciprocating manner on the syringe mating end surface of the cylinder.

The suction port is equipped with a check valve for suction, and the discharge boat is equipped with a check valve for discharge.The reciprocating motion of the plunger sucks oil from the suction port and pumps oil from the discharge port. It is possible to discharge in this condition.

Here, for example, in the case of the -1-2 separation lubricating device.

In order to ensure normal and economical operation of Mukuro Seki,
The oil mixture ratio with respect to the consumption amount is increased or decreased to an appropriate value, for example, i;o-1/2oo, depending on the increase or decrease in the rotational speed of one engine. Therefore, in order to maintain an appropriate oil mixing ratio in the separation and lubricating device, the plunger type oil pump has a discharge ffi per stroke of the plunger.
It is desirable that the number be increased to 11.

However, in conventional sylanger type oil pumps, if air enters from the gap between the cylinder and the plunger, from each boat, etc., even if the plunger reciprocates with a minute stroke corresponding to a slight fft oil, the intruding air will Just by repeating expansion and contraction.

In many cases, it is not possible to activate the suction check valve at the suction port and the discharge check valve at the discharge port, so a recirculator is required to obtain a small amount of oil.

SUMMARY OF THE INVENTION An object of the present invention is to provide a sylanger-type oil pump that can reliably suck in and discharge a small amount of oil even when air enters the cylinder.

In order to achieve the above object, the plunger type oil pump according to the present invention is provided with a sub-discharge port having a smaller opening pressure than the opening pressure of the discharge reverse valve on the side surface of the cylinder. This is what I did.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a side view showing a separate lubrication system for an outboard motor to which the present invention is applied, and FIG. 2 is a piping system diagram showing an embodiment of the present invention.

In FIG. 1, an outboard motor 10 has a clamp bracket 11
It is possible to attach it to the hull through the casing 12.
A 2-cylinder 2-stroke engine 1st is mounted on top of the engine. The engine 13 has a carburetor 14.15 corresponding to each cylinder?
In addition, a flywheel magnet 16 is provided at the upper end of the crankshaft. Further, a propeller 17 is connected to the lower end of the crankshaft of the engine 13 via a drive shaft vertically installed within the casing 12 .

Further, 18 is a fuel tank, and the fuel tank 18 is mounted inside the hull and communicated with a fuel pump 20 via a pipe 19. The fuel pump 20 is of a diaphragm type and can be driven using the intake negative pressure of the engine 13.
- Fuel can be supplied to the carburetor 14.15 via the Zeizo 21.22.

That is, the fuel in the fuel tank 18 is transferred to the fuel pump 20.
After being supplied to the carburetor 14, 15 by the operation of , it is possible to evenly distribute it to the crank chamber of the cylinder even in a state where it is mixed with air.

In addition, a connecting pipe 23° pipe 24 and a plunger type oil pump 25 are connected to the intermediate part of the pipe 19.
An oil tank 26 is connected.

The oil pump 25, which will be detailed later, includes an electromagnetic solenoid,
The oil in the oil tank 26 can be discharged by operating a drive unit 27 made of an electric motor or the like. That is, when the outboard motor 10 is operated, the drive section 2 of the oil pump 25
7 is operated, the oil in the oil tank 26 is mixed with the fuel in the pipe 19, and the oil thus mixed in the fuel is mixed with the fuel in the carburetor 14.7 under the operation of the fuel pump 20. After being supplied to the engine 15, it is distributed evenly to the crank chambers of each cylinder, and after lubricating each part of the engine, it is burned and consumed. It should be noted that a manual pump 12B is interposed in one of the two positions shown in FIG. This manual pump 28 supplies fuel in advance to the fuel pump 20 provided on the engine 13 side before starting the engine, thereby preventing the fuel pump 20 from running idle and enabling a smooth start.

Further, the flywheel magneto 16 is provided with a pulser coil 29 that generates pulse signals equal to the number of cylinders per revolution of the crankshaft, that is, twice in this embodiment. The ξ pulse signal generated by the pulser coil 29 can be transmitted to the rotational speed detector 30. The rotational speed detector 30 is capable of detecting the engine rotational speed of the engine 13 by counting the pulse signal deposit generated by the /e Lusa coil 29 within a unit time. Note that the rotational speed detector 30 includes a frequency-voltage conversion circuit and outputs a voltage value proportional to the engine rotational speed.

The output value of the rotation speed detector 30 is determined by the oil amount setting device 31.
is transmitted to. The oil amount setting device 31 has an engine 13
For each engine rotational speed, the optimum oil mixture ratio for the fuel consumption at that time, and thus the optimum oil supply air, are determined in advance using a map or a functional formula.

Therefore, the oil amount setting device 31 is connected to the rotation speed detector 3.
Based on the detection result of 0, it is possible to output the optimum oil Jle voltage value corresponding to the engine rotation speed. The output value of the oil amount setting device 31 is subjected to voltage-frequency conversion in a pulse oscillator 32. This J? During the conversion process, the pulse oscillator 32 outputs a pulse frequency-divided to match the number of discharges per unit time of the oil pump 25,
The signal is transmitted to the drive section 27 of the oil pump 25.

Here, as shown in FIG. 2, the oil pump 25 includes a suction port 37 equipped with a suction check valve 36 on a syringe abutting end surface 35 of a cylinder 34 in which a plunger 33 is reciprocally accommodated; and a discharge port 39 equipped with a discharge check valve 38. Further, a sub-discharge port 41 is provided on the side surface of the cylinder 34 and includes a check valve 40 whose opening pressure is smaller than that of the discharge oil check valve 38 .

Further, the entire stroker HITh of the syringer 33 is larger than the pushing stroke H2 of the syringer 33 after the sub-discharge port 41 is closed.

Next, the operation of the above embodiment will be explained.

When the engine 13 is operating, the oil amount setter 31 sets the optimum oil level corresponding to the engine rotational speed signal detected by the pulser coil 29 and the rotational speed detector 30°, and the drive unit 2T of the oil pump 25 operates as described above. It is driven based on the settings made by the oil amount setting device 31, and supplies an appropriate amount of oil into the fuel that can form the optimum mixture ratio for the engine rotational speed.

Here, the pushing stroke H2 of the sylanger 33 after closing the sub-discharge port 41 in the oil pump 25 is
If the pushing volume determined by is set to a small predetermined volume, (1) as shown in FIG. Even if there is air intrusion into the cylinder 34, it is possible to reliably suck all of the oil beyond a predetermined volume into the cylinder 34, and then (2) Fig. 3 (C)
As shown in ~◎, by pushing the plunger 33 from the retreating end position to the closing position of the sub-discharge port 41, surplus oil exceeding the predetermined volume is discharged from the sub-discharge port 41.

Next, (8) plunger 3 as shown in FIG.
3, it becomes possible to obtain the predetermined volume of oil from the discharge port 39. Note that since the opening pressure of the check valve 40 is smaller than the opening pressure of the discharge check valve 38, the distance from the retreating end position of the sylanger 33 to the closing position of the sub-discharge port 41 is During pushing, only the check valve 40 opens, the discharge check valve 38 remains closed, and no oil is discharged from the discharge port 39.

Therefore, the oil pump 25 is able to make the discharge m per one stroke of the syringer 33 a very small amount, and even when the oil amount set by the oil amount setting device 31 is a very small amount, the oil pump 25 The small amount of oil is accurately supplied to the engine 13 side, making it possible to ensure normal and economical operation of the engine 13.

As described above, in the plunger type oil pump according to the present invention, the sub-discharge port is provided on the side surface of the cylinder and is equipped with a reverse IE valve whose opening pressure is smaller than the opening pressure of the discharge check valve. This is how it was done. Therefore, if the pushing volume determined by the pushing stroke of the sylanger after the sub-discharge boat is closed is set to a small predetermined volume, by retracting the sylanger from the opening position of the sub-discharge port,
Even if there is air intrusion into the cylinder, it is possible to reliably draw more than the specified volume of oil into the cylinder. .

By discharging surplus oil in an amount equal to or greater than the predetermined volume from the sub-discharge port and then pushing the sylanger to the forward end position, it becomes possible to obtain the minute amount of oil in the predetermined volume from the discharge port. That is, even if air enters the cylinder, it is possible to completely reliably suck in and discharge a small amount of oil.

[Brief explanation of the drawing]

Fig. 1 is a side view showing a separate lubrication system for an outboard motor to which the present invention is applied, Fig. 2 is a piping system diagram showing an embodiment of the present invention, and Fig. 3 (4) to (g) are the same. FIG. 3 is an operating state diagram of the embodiment. 25...Oil pump, 33...Siranja, 34
...Cylinder, 35.°°butting end surface 36.. Check valve for suction, 37.. Suction port, 38.. Backward valve for discharge. 39...Discharge port, 40...Check valve, 41...
Sub-discharge port. Agent Patent Attorney Osamu Shiokawa

Claims (1)

[Claims] (1) A syringe-type oil in which a suction boat equipped with a suction check valve and a discharge port equipped with a discharge check valve are provided on the syringe joint end face of a cylinder in which a plunger is housed so as to be able to reciprocate. A silanger-type oil pump characterized in that a sub-discharge port is provided on the side surface of the cylinder with a check valve whose opening pressure is smaller than the opening pressure of the discharge check valve.