JP2750917B2 - Engine lubrication device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to, for example, an engine of a rotary piston engine having a metering oil pump for supplying metering oil to an inner peripheral surface of a trochoid of a rotor housing. It relates to a lubrication device.

(Prior Art) In general, in a rotary piston engine, metering oil is metered and supplied to the inner peripheral surface of the trochoid of the rotor housing in order to improve the lubricity of the apex seal, and the lubricating oil supply device is driven by an eccentric shaft. The used metering oil pump is used.

As an lubricating device for an engine provided with the above-mentioned metering oil pump, there is, for example, a device described in JP-A-62-157202.

That is, an engine including a metering oil pump that supplies metering oil to a working chamber of a rotary piston engine, a control pin that controls a position of a plunger of the metering oil pump, and a stepping motor that drives the control pin. It is a lubrication device.

This device usually includes a position sensor for detecting the position of the control pin described above, and a feedback control system for controlling the stepping motor based on an output signal of the position sensor. In addition to variably controlling the amount of metering oil supplied from the pump, when the above-mentioned position sensor cannot perform feedback due to disconnection, short circuit, or poor contact, the CPU injection controls the fuel injection pulse width and ignition advance value to backup values. By fixing
It is configured to prevent engine seizure.

However, the above-described conventional apparatus configured as described above has the following problems.

In other words, since the above-described CPU input stage is provided with a filter circuit for preventing noise from the position sensor, a failure such as a disconnection or a short circuit occurs in the position sensor, and the voltage change causes a failure of the CPU. It takes some time to reach the judgment level. During this time, the CPU cannot make a failure judgment and performs erroneous feedback control assuming that it is a normal voltage change. When the level reaches the failure judgment, the position of the stepping motor becomes undefined, and as a result, when the control pin driven by the stepping motor reaches the increased position, a large amount of metering oil is supplied to the inner peripheral surface of the trochoid. And the spark plug fogging phenomenon (a phenomenon in which a large amount of oil adheres to the spark plug and the ignitability deteriorates) occurs. There was a point.

(Problems to be Solved by the Invention) The present invention is to prevent a large amount of metering oil from being supplied to the working chamber of an engine when a position sensor or the like fails, and to reliably prevent fogging of a spark plug. An object of the present invention is to provide a lubricating device for an engine.

(Means for Solving the Problems) The present invention provides a metering oil pump that supplies metering oil to an operating chamber of an engine, a control pin for controlling the position of a plunger of the metering oil pump, and driving of the control pin. An engine lubricating apparatus comprising: a motor to be controlled; a position sensor for detecting a position of the control pin; and control means for controlling the motor based on an output signal of the position sensor. Failure determining means for detecting and determining a failure; and, based on the failure determination output of the failure determining means, the control pin is fixedly held at a reduced position of the metering oil via the motor, and the fuel injection amount is reduced to a predetermined low value. And a fixed control means for fixedly holding the lubrication device.

(Effects of the Invention) According to the present invention, when a failure such as a disconnection or a short circuit occurs in the position sensor or the like, the failure determination means detects and determines the failure, and based on the failure determination output, Fixed control means fixedly holds the control pin at the reduced position of the metering oil via the motor.

As a result, a large amount of metering oil is prevented from being supplied to the working chamber of the engine when a position sensor or the like fails,
This has the effect of reliably preventing fogging of the spark plug.

At the same time, the above-mentioned fixed control means fixedly holds the fuel injection amount at a predetermined low value, thereby preventing seizure of the engine,
There is an effect that the engine can be protected.

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

The drawing shows a lubrication device for a rotary piston engine,
In FIG. 1, a rotary piston engine 1 has a rotor housing 2 composed of a base material and a liner made of a hard chrome plating layer formed on the inner peripheral surface of the base material, and operates inside a peritrochoid surface of the rotor housing 2. A chamber 3 is formed.

An intake port 4 and an exhaust port 5 are formed on one side of the rotor housing 2, and a trailing-side ignition plug 6 and a leading-side ignition plug 7 are arranged on the other side.

A rotor 10 eccentrically moved about an axis 9 by an eccentric shaft 8 is provided in the rotor housing 2 described above.

The rotor 19 has a three-leaf inner envelope surface, and an apex seal is attached to the top of the rotor.

On the other hand, an air flow meter 12, an air intake hose 13, a turbocharger 14, an intercooler 1
5, an intake manifold 18 is connected via a throttle body 16 and a surge tank 17, and the intake manifold 18 is connected to the above-mentioned intake port 4 and the exhaust port 5 is connected to an exhaust manifold 19. I have.

In the vicinity of the intake port 4 in the rotor housing 2, metering oil is supplied to the rotary piston engine 1.
The so-called oil supply hole 20 for directly supplying the working chamber 33, specifically the inner peripheral surface of the trochoid, is formed with the oil discharge nozzle 21 of the direct oil supply system.

Here, an air inlet tube 22 and a metering oil tube 23 are attached to the above-described oil discharge nozzle 21, and the above-mentioned air inlet tube 22 is connected to the air intake hose 13, while the above-mentioned metering oil tube 23 is Connected to the discharge hole 25 of the oil pump 24 (see FIG. 2), the metering oil is pushed out to the inner surface of the trochoid using the air from the air inlet tube 22 and the air supercharged by the turbocharger 14. Make up.

As shown in FIG. 2, the above-mentioned metering oil pump 24 has a control pin 28 housed in a pin arrangement hole 27 of a pump housing 26, a plunger 29 arranged in a direction orthogonal to the control pin 28, and Differential plunger
30; a sub-plunger 31 disposed in the differential plunger 30; a spring retainer 32 attached to one end of the sub-plunger 31; and a plunger which is stretched between the differential plunger 30 and the spring retainer 32 described above. A spring 33 for biasing the control pin 28 toward the control pin 28; a variable resistance type position sensor 36 for detecting the vertical position of the control pin 28 via a sensing lever 34 and a sensing rod 35; A stepping motor 37 for driving the stepping motor 37 in the vertical direction, and a return spring 38 for urging the control pin 28 to the maximum decreasing position of the metering oil (fully closed position) when energization of the stepping motor 37 is cut off. ing.

A worm wheel 29a formed on the plunger 29 is connected to the eccentric shaft 8 via a driving worm and a driven gear, and the suction hole 39 is formed by the rotation and reciprocating linear movement of the plunger 29.
It is configured to discharge oil (metering oil) sucked in from the above to the metering oil tube 23 from the above-described discharge hole 25.

Further, the control pin 28 linked to the stepping motor 37 is moved up and down by a signal from the CPU 40, and the reciprocating stroke of the plunger 29 is variably controlled in accordance with the up and down position of the control pin 28, so that It is configured to adjust the discharge amount of ring oil.

Furthermore, while connecting the position sensor 36 and the CPU 40 with a line 41, a so-called wire harness,
Connect U40 and stepping motor 37 with line 42,
A feedback control system 43 composed of these elements 40, 41, 42
And a stepping motor 37 based on the output signal of the position sensor 36 by the feedback control system 43.
Is configured to perform feedback control.

By the way, as shown in FIG. 1, the CPU 40 has a throttle opening TVO, an engine speed Ne, a water temperature Tw, and an intake air temperature T.
i, drive control of the stepping motor 37, the injector 45, the trailing-side igniter coil 46, and the leading-side igniter coil 47 in accordance with a program stored in the ROM 44 based on various input signals such as the sensor voltage V;
M48 stores necessary data such as a fail judgment lower limit Fb, a fail judgment upper limit Ft, and data of various set values A and B (see FIGS. 3 and 4).

Here, the CPU 40 described above meta-connects the control pin 28 via a stepping motor 37 based on failure determination means for detecting and determining a failure of the position sensor 36 and the feedback control system 43 and a failure determination output of the failure determination means. It also serves as fixed control means for fixedly holding the ring oil at the maximum reduction position and for holding the fuel injection amount at a predetermined low value (backup value).

The illustrated embodiment is configured as described above.
The operation will be described with reference to the flowchart of FIG.

In a first step 51, the CPU 40 executes reading processing of various signals such as the sensor voltage V, the throttle opening TVO, the engine speed Ne, the water temperature Tw, the intake temperature Ti, and the like.

Next, in a second step 52, the CPU 40 compares the current sensor voltage V with a fail determination lower limit Fb (voltage value data) stored in the RAM 48 in advance to execute a fail determination, and Fb <V
When the line breaks (failure), the process proceeds to the next seventh step 57, while when Fb <V, the process proceeds to another 32nd step 53.

In this third step 53, the CPU 40 sets the current sensor voltage V
And a fail determination upper limit Ft (voltage value data) stored in the RAM 48 in advance to perform a fail determination. When Ft <V is short-circuited (failure), the process proceeds to the seventh step 57 described above. When Ft> V, the process proceeds to the next fourth step 54.

In the fourth step 54, the CPU 40 determines whether or not the control target value is constant. When the control target value is constant, the CPU 40 proceeds to the next fifth step 55. On the other hand, when the control target value is variable, another thirteenth step 63,
17 Go to step 67.

In the above-described fifth step 55, the CPU 40 determines whether or not the current sensor voltage V has decreased. When the sensor voltage V is constant or increases, the above-described thirteenth step 63 and the seventeenth step
On the other hand, when the sensor voltage V decreases, the next sixth
Move to step 56.

In the sixth step 56, the CPU 40 determines the sensor voltage drop amount Δ
V is compared with a set value A previously stored in the RAM 48, and Δ
When V> A fails, the process proceeds to the seventh step 57 described above. On the other hand, when ΔV <A, the process proceeds to the thirteenth step 63 and the seventeenth step 67.

Here, the stepping motor 37 loses synchronism (step-out,
When synchronization is lost, the rotation stops following the input pulse, and the position sensor 36 as a position sensor is not used.
However, since the sensor voltage drop occurs as described above, the drop amount is smaller than the drop amount at the time of a failure, and therefore, out-of-step and failure are determined based on the magnitude of the sensor voltage drop.

When the CPU 40 executes the sensor failure determination process in the above-described seventh step 57, the process proceeds to the following eighth step 58, tenth step 60, and twelfth step 62.

Eighth step 58, ninth step 59 described below, and
The tenth step 60, the eleventh step 61, and the twelfth step 62 are processed in parallel.

In the above-described eighth step 58, the CPU 40 fixes the fuel injection pulse width to a predetermined low value, for example, a backup value.

Next, in a ninth step 59, the CPU 40 outputs the above-mentioned fixed value to the injector 45.

Further, in the above-described tenth step 60, the CPU 40 fixes the ignition advance value to, for example, a backup value, and then in the next eleventh step 61, the CPU 40 sets the trailing-side igniter coil 4
6. The ignition of the ignition plugs 6, 7 is controlled by the above-mentioned fixed value via the leading side igniter coil 47.

Further, in the above-described twelfth step 62, the CPU 40 executes the energization cut for the stepping motor 37.

When the power supply to the stepping motor 37 is cut off,
Since the control pin 28 moves to the maximum reduction position (fully closed position) by the spring force of the return spring 38 shown in FIG. 2, the discharge amount of the metering oil from the metering oil pump 24 is maintained at the maximum reduction amount.

As described above, when a failure such as a disconnection, a short circuit, or a contact failure occurs in the position sensor 36, the second step 52, the third step 53, and the sixth step
56 and a seventh step 57 detect and determine the failure, and based on the failure determination output, an eighth step 58 and a twelfth step 62 as a fixed control means meter the control pin 28 via the stepping motor 37. The fuel injection amount is fixedly held at the oil decreasing position, and the fuel injection amount is fixedly held at a predetermined low value.

As a result, when the position sensor 36 fails, a large amount of metering oil is supplied to the working chamber 3 of the rotary piston engine 1.
To prevent the ignition plugs 6 and 7 from fogging, and at the same time, since the fuel injection amount is fixedly held at a predetermined low value, the rotary piston engine 1 There is an effect that the seizure can be prevented and the rotary piston engine 1 can be protected.

Note that normal fuel control and ignition control other than during a failure are as in steps 63 to 70, and steps 63 to 66 are performed.
And steps 67 to 70 are performed in parallel.

That is, in the above-described thirteenth step 63, the CPU 40 calculates the basic injection pulse, and in the next fourteenth step 64, the CPU 40 calculates the fuel increase rate in accordance with the engine operating conditions, and
In 15 step 65, the CPU 40 calculates the actual injection pulse width. In the next 16th step 66, the CPU 40 outputs the above-described calculated value to the injector 45 to execute fuel control.

In addition, in the above-described seventeenth step 67, the CPU 40 calculates the basic advance value, and in the next eighteenth step 68, the CPU 40 calculates a correction value corresponding to the engine operating condition, and in the next nineteenth step 69
Then, the CPU 40 calculates the actual advance value, and the next 20th step 70
The CPU 40 is connected to the ignition plugs 6 and 7 via the trailing-side igniter coil 46 and the leading-side igniter coil 47.
Is controlled by the above calculated value.

FIG. 4 shows another embodiment of a lubricating device for a rotary piston engine. In this embodiment, the shaft of the position sensor 36, that is, the stepping motor 37 is cut off when the sensing rod 35 is fixed. Make up.

That is, in the first step 81, the CPU 40 subtracts the actual position Co from the control target Ct (Ct−Co) and the RAM 48 in advance.
Is compared with the set value B stored in the second step 82. When Ct−Co> B, the process proceeds to the next second step 82.

In this second step 82, the CPU 40 feeds back the difference (Ct−Co).

Next, in a third step 83, the CPU 40 compares the subtraction value (Ct-Co) after the third feedback with the set value B, and when Ct-Co> B, that is, the axis of the position sensor 36 is fixed. When the feedback is not performed, the process proceeds to the next fourth step 84.

In the fourth step 84, the CPU 40 executes the feedback failure determination processing, and then proceeds to the next fifth step 85.

In the above-described fifth step 85, the CPU 40 fixes the ignition advance value to the backup value, fixes the fuel injection pulse width to the backup value, and cuts off the power supply to the stepping motor 37.

As a result, the control pin 28 can be fixedly held at the maximum reduction position (fully closed position) of the metering oil by the action of the return spring 38, and the fuel injection amount can be fixedly held at a predetermined low value. A large amount of metering oil can be prevented from being supplied to the working chamber 3 of the rotary piston engine 1 when the shaft of the position sensor 36 is stuck and the ignition plugs 6 and 7 can be reliably prevented from fogging. There is an effect, and at the same time, since the fuel injection amount is fixedly held at a predetermined low value, it is possible to prevent seizure of the rotary piston engine 1 and protect the rotary piston engine.

In the correspondence between the configuration of the present invention and the above-described embodiment, the engine of the present invention corresponds to the rotary piston engine 1 of the embodiment. Hereinafter, similarly, the motor corresponds to the stepping motor 37, and the position sensor is The control means corresponds to the feedback control system 43 including the CPU 40, and the failure determination means corresponds to each of the steps 52, 53, 5 based on the control of the CPU 40.
6, 57, 83, 84, and the fixed control means controls each step 58, 62, 8
Although corresponding to 5, the present invention is not limited to only the configuration of the above-described embodiment.

[Brief description of the drawings]

1 shows an embodiment of the present invention, FIG. 1 is a system diagram showing a lubricating device for a rotary piston engine, FIG. 2 is a sectional view showing an internal structure of a metering oil pump, FIG. FIG. 11 is a flowchart showing another embodiment. 1 Rotary piston engine 3 Working chamber 24 Metering oil pump 28 Control pin 29 Plunger 36 Position sensor 37 Stepping motor 40 CPU 43 Feedback control system (control means) 52: second step (failure determining means) 53: third step (failure determining means) 56: sixth step (failure determining means) 57: seventh step (failure determining means) 58: eighth Step (fixed control means) 62 ... 12th step (fixed control means) 83 ... 3rd step (failure determination means) 84 ... 4th step (failure determination means) 85 ... 5th step (fixed control means)

Claims (1)

(57) [Claims] 1. A metering oil pump for supplying metering oil to a working chamber of an engine, a control pin for controlling a position of a plunger of the metering oil pump, a motor for driving the control pin, A lubricating device for an engine, comprising: a position sensor for detecting a position; and control means for controlling the motor based on an output signal of the position sensor, wherein failure determination means for detecting failure of the position sensor and the control means. And fixed control means for fixedly holding the control pin at the reduced position of the metering oil via the motor based on the failure determination output of the failure determination means, and for fixedly maintaining the fuel injection amount at a predetermined low value. Engine lubrication device equipped with.