JPH0723684B2 - Engine lubrication oil supply device - Google Patents

Abstract

PURPOSE:To suppress the driving power to the necessary min. value by adjusting the reciprocation stroke quantity of a plunger for supplying lubricating oil under pressure by a control cam and increasing the driving power of an electric motor when a deviation is generated between the actual position of the control cam and the aimed position corresponding to the operation state. CONSTITUTION:The first and second plungers 32 and 33 are arranged in parallel and in free reciprocation in a pump housing 31, and perform the metering and discharge of the lubricating oil for the oil supply to ports and for the direct oil supply, respectively. The gear parts 32a and 33a of the first and second plungers 32 and 33 are revolution-driven by a driving worm interlocked with the output shaft of an engine, and the stroke quantity is adjusted by the contact of a control cam 36 with the cam surface. The driving power of a step motor 21 for feedback-controlling the control valve cam 36 to the aimed value corresponding to the operation state on the basis of the detection value of a position sensor 28 is increased when a deviation is generated between the aimed value and the actual value.

Description

TECHNICAL FIELD The present invention relates to a supply oil supply device for an engine.

(Prior Art) In a rotary piston engine or a two-cycle reciprocating engine, lubricating oil is supplied into the working chamber (combustion chamber). In order to change the amount of this lubricating oil according to the operating condition of the engine, there is a type using a plunger as shown in Japanese Patent Laid-Open No. 606001. This one is
Basically, a pump chamber whose volume is changed by the reciprocating motion of the plunger is configured, and the volume change amount of the pump chamber, that is, the lubricating oil discharge amount is changed by changing the reciprocating stroke amount of the plunger. There is. And
The amount of reciprocating stroke of the plunger is performed by changing the displacement position of the control cam with which the plunger contacts, based on the engine load.
For example, the operation is performed by mechanically linking the throttle valve and the control cam via a wire.

(Problems to be solved by the invention) By the way, recently, in order to reduce the consumption of lubricating oil or change the supplied lubricating oil amount to a more appropriate value according to the operating state of the engine, the control cam described above is used. It is considered that the operation of the electric motor is controlled according to the operating state of the engine while being driven by.

When the control cam is driven by this electric motor, one problem is how to set the driving force of the electric motor. Explaining this point in detail, it is desired that the electric motor generate a driving force that is as small as possible in consideration of ensuring its durability and reducing power consumption. In particular, when a general step motor is used as the control electric motor, the larger the driving force becomes, the worse the response speed becomes. Therefore, a small driving force is required from the viewpoint of ensuring the responsiveness. It will be strongly desired to generate.

On the other hand, the driving force required to drive the control cam changes due to various factors. For example, when the viscosity resistance of the lubricating oil is large at low temperature, a large driving force is required to drive the control cam. Therefore, if the driving force of the electric motor is uniformly set to be small, the electric motor is driven to a predetermined target position according to the operating state of the engine, that is, a predetermined lubricating oil supply amount is obtained. Will be difficult.

The present invention has been made in consideration of the above circumstances,
As the driving force of the electric motor that drives and displaces the control cam,
It is an object of the present invention to provide a lubricating oil supply device for an engine, which is set to be small at all times and is capable of reliably driving a control cam.

(Means and Actions for Solving Problems) In order to achieve the above-mentioned object, the present invention has a configuration as shown in FIG. That is, in the engine lubrication oil supply device in which the reciprocating stroke amount of the plunger for pumping the lubrication oil to the engine is adjusted by the control cam with which the plunger contacts, in order to displace the control cam. Electric motor, operating state detecting means for detecting the operating state of the engine, target position determining means for determining the target position of the control cam in accordance with the operating state of the engine, and the electric motor for setting the target position. Drive control means for controlling the drive of the control cam, position detection means for detecting the actual position of the control cam, deviation detection means for detecting the deviation between the target position and the actual position, and the electric motor as the target position. When driving so that
When a deviation occurs between the target position and the actual position,
And a driving force correcting means for increasing the driving force of the electric motor.

With such a configuration, the electric motor only needs to generate the minimum necessary driving force commensurate with the drive displacement of the control cam, and ensures the durability of the electric motor and the reliable driving of the control cam. Both can be satisfied at the same time.

(Example) Hereinafter, an example of the present invention will be described with reference to the accompanying drawings.

In FIG. 1, a casing 1 of a rotary piston engine is composed of a rotor housing 2 having a trochoidal inner peripheral surface 2a and side housings 3 arranged on both sides thereof. Further, a substantially triangular rotor 4 which makes a planetary rotational movement in the casing 1 is supported by an eccentric shaft 5,
Three working chambers 6 are formed in the casing 1 by partitioning,
With the rotation of the rotor 4, intake, compression, explosion, expansion, and exhaust processes are sequentially performed. The inner peripheral surface of the rotor housing 2 is provided on each top of the rotor 4.
The apex seal 7 slidingly contacting the 2a is attached to the rotor 4
Side seals 8 which are in sliding contact with the inner surface of the side housing 3 are mounted on both side surfaces of the rotor, and corner seals 9 are mounted on both ends of each top of the rotor 4.

The casing 1 is provided with an intake port 10 that opens to the working chamber 6 in the intake stroke through the side housing 3, and an exhaust port 11 that opens to the working chamber 6 in the exhaust stroke through the rotor housing 2. An intake passage 12 or an exhaust passage 13 is connected to the intake port 10 and the exhaust port 11. Further, a pair of spark plugs 14 are mounted at predetermined positions of the rotor housing 2, and an injector 15 for injecting fuel is installed in the intake passage 12 near the intake port 10.

A port refueling nozzle 16 is attached to face the intake passage 12, and the lubricating oil discharged from the port refueling nozzle 16 through the port refueling port 16a is refueled into the casing 1 through the intake passage 12. In addition, the rotor housing 2
Direct oiling nozzle 17 is attached facing the inner peripheral surface 2a of this, and from this direct oiling nozzle 17 direct oiling port
The lubricating oil discharged through 17a is directly supplied to the casing 1. The port lubrication nozzle 16 is connected to a first lubrication oil supply passage 18 extending from a metering oil pump 20 as a lubrication lubrication oil metering device, and the direct lubrication nozzle 17 is extended from the metering oil pump 20. 2 The lubricating oil supply passage 19 is connected. Air passages 16b and 17b are connected to the ports and the direct fueling nozzles 16 and 17, respectively.

The engine shown in the figure has two cylinders, and a port oil supply nozzle 16 for port oil supply and a direct oil supply nozzle 17 for direct oil supply are provided in cylinders not shown as well, and lubricating oil is separately supplied from the metering oil pump 20. aisle
18, 19 are connected.

The metering oil pump 20 is designed to measure and discharge lubricating oil, and the discharge amount is set to the control unit 25 (ECU) for the step motor 21 as an electric motor.
By outputting a control signal from the engine, it is controlled according to the operating state of the engine. The control unit 25 receives signals from an air flow meter 26 for detecting the intake air amount, a rotation speed sensor 27 for detecting the engine speed, and a position sensor 28 for detecting the actual position of the control cam 36. .

2 to 4 show the specific structure of the above-mentioned metering oil pump 20, and in the pump housing 31,
A first plunger 32 for measuring and discharging the lubricating oil for port lubrication and a second plunger 33 for measuring and discharging the lubricating oil for direct lubrication are arranged parallel to each other and reciprocally movable. Has been done. Both plungers
Each of 32 and 33 is divided into a front portion and a rear portion, and central holes of the rear portion are fitted and inserted into pins 34 and 35 (fixed to the housing 31 side), respectively.

Further, the pump housing 31 includes the plungers 32, 33.
A shaft-shaped control cam 36 extending in a direction orthogonal to the axis is slidably inserted in the axial direction. The control cam 36 has first and second cam surfaces 36a and 36b with which the tips of the plungers 32 and 33 come into contact, and the first and second cam surfaces 36a and 36b.
Each of a and 36b is formed in a tapered surface shape whose cross-sectional area changes in the axial direction.

The plungers 32, 33 are biased toward the control cam 36 by springs 37, 38 arranged on the outer circumferences of the pins 34, 35. Further, the plungers 32, 33 have gear portions 32a, 33a, are engaged with the gear portions 32a, 33a, and are associated with the engine output shaft, the driving worm 39.
It is driven to rotate by. The tips of the plungers 32, 33 have both side ears 32b, 33b and central protrusions 32c, 33c.
The b and 33b reciprocate by being displaced into a state in which they ride on the base circle 36c of the control cam 36 and a state in which the central convex portions 32c and 33c are in contact with the cam surfaces 36a and 36b. By the rotation and reciprocating movement of the plungers 32 and 33, the volumes of the measuring chambers 32d and 33d defined inside the plungers 32 and 33 (in front of the pins 34 and 35) are displaced,
Suction of lubricating oil from each suction port 40 and discharge port 41a
The discharge of lubricating oil to ~ 41d is alternately repeated.

That is, the lubricating oil is introduced from the journal portion of the driving worm 39 to the outer peripheral portion of the control cam 36, and from there, the suction passage 42 formed in parallel with the plungers 32 and 33 opens on both sides orthogonal to the plungers 32 and 33. Introduced into the suction port 40. On the other hand, in the plungers 32 and 33, suction ports 32e and 32e are opened at positions where the plungers 32 and 33 can communicate with the suction port 40, and the discharge ports 32f and 33f are axially displaced and opened, so that the discharge ports 41a to 41a of the pump housing 31 41d is the suction port
It opens on both sides orthogonal to 40. Then, the first lubricating oil supply passages 18, 18 for port lubrication to the first and second cylinders are connected to the two first discharge ports 41a, 41b corresponding to the first plunger 32, and the second plunger 33 For the two second discharge ports 41c, 42d corresponding to
Second lubrication oil supply passages 19 and 19 for direct lubrication to the cylinders
Are connected.

The movement of the control cam 36 in the axial direction is performed by a stroke type step motor 21. The shaft 21a, which is moved back and forth in the axial direction of the step motor 21, is arranged coaxially with the control cam 36, and the control cam 36 is urged by the return spring 23 so that one end thereof is brought into pressure contact with the shaft 21a. Has been done. Therefore, the control cam 36 is displaced downward (increase direction) in FIG. 2 by the driving force of the step motor 21, and is displaced upward (decrease direction) by the urging force of the return spring 23. Of course, the step motor 21 receives the pulse signal output from the control unit 25 and slides the control cam 36 by one step (constant length) with the output of one pulse.

As shown in FIG. 2, the position sensor 28 includes a main body 28a screwed and fixed to a pump housing 31, and a tentacle 28b that is held by the main body 28a so as to be movable back and forth and is always biased in a protruding direction.
And the tip of the contactor 28b is always in contact with the tapered surface 36g formed on the control cam. As a result, the probe 28b is moved back and forth according to the displacement of the control cam 36, and a signal (generally a voltage) corresponding to the forward / backward position of the probe 28b is output from the main body 28b. Of course, the position sensor 28 may indirectly detect the position of the control cam 36, such as detecting the displacement position of the shaft 21a of the step motor 21.

In the above metering oil pump 20, the control cam 36
By changing the radius of each cam surface 36a, 36b due to sliding, the moving stroke of each plunger 32, 33 is changed, and the amount of lubricating oil discharged per unit speed of the engine is changed. And
The discharge amount per unit rotational speed can be electrically controlled by the control unit 25 via the step motor 21, and the discharge amount characteristic is port lubrication depending on the shape of each cam surface 36a, 36b. Can be set individually for direct refueling. Therefore, by differentiating the shapes of the cam surfaces 36a and 36b in advance, the step motor 21 is configured so that the discharge amount and the discharge ratio from the discharge ports 41a to 41d are variously changed by the change in the axial direction of the control cam 36. The discharge amount and the discharge ratio can be controlled according to the operating state by the control.

Number of steps in this step motor 21 (cam position)
FIG. 5 shows an example of setting the oil discharge amount and the lubricating oil discharge amount.
Of course, the characteristics shown in FIG. 5 can be set independently on the plunger 32 side and the 33 side, respectively, as described above (port oil supply and direct oil supply ratio setting).

In the above-described embodiment, when the amount of lubricating oil discharged is increased, the control cam 36 is moved downward in FIG. 2 (a pulse is output in the direction of increasing the number of steps) to reduce the radius of the cam surfaces 36a, 36b. Center protrusion 32 on the tip of plunger 32, 33
The c and 33c are brought into contact with each other, and the difference from the base circle 36c, that is, the stroke amount is increased. On the other hand, when the discharge amount is reduced, a pulse is output in the direction of decreasing the number of steps and the control cam 36 is moved upward in FIG.

Now, next, regarding the control contents by the control unit 25,
In the embodiment, the control unit 25 is basically composed of a microcomputer including a CPU, a ROM, and a RAM, which will be described with reference to the flowchart shown in the drawing. Further, in the embodiment, the driving force of the step motor 21 is adjusted by changing the pulse speed output to the step motor 21. That is, as a characteristic of the step motor 21, as the pulse speed increases, its driving force decreases (see FIG. 7) and its operating speed increases (see FIG. 6). In the following description, P indicates a step.

First, at P1, intake air amount Q, engine speed N,
The number of steps Ik ₁ indicating the current displacement position of the control cam 36 is read. Next, at P2, the intake air amount per one revolution of the engine is multiplied by a predetermined constant K to calculate the step number Ikm indicating the target cam position, that is, the target lubricating oil amount according to the operating state of the engine. After that, in P3, the number of movement steps Si ₁ required to reach the target cam position Ikm is calculated by subtracting the number of steps Ik ₁ indicating the current cam position from the number of steps Ikm indicating the target cam position.

After P3, at P4, the pulse speed Ps ₁ is set to correspond to the large pulse speed S ₁ (small driving force), and then at P 5, with this large pulse speed S ₁ ,
A pulse is emitted to achieve the number of moving steps Si ₁ at P3.

Next, at P6, the actual position Ik ₂ of the step motor 21 is confirmed according to the output of the position sensor 28. Thereafter, in P7, whether the actual position Ik ₂ has been identified in a target position Ikm and P6 determined in P2 coincides it is discriminated. If the determination in P7 is NO, it means that the driving force of the step motor 21 is insufficient and the target position Ikm cannot be reached, so the processes in P8, P9, and P10 are performed. That is, P
In 8, moving step number Si ₂ corresponding to the deviation of the actual position and the target position IKM Ik ₂ is calculated. Further, in P9, a pulse speed S ₂ smaller than the pulse speed S _{1 in} P5 is set as the pulse speed Ps ₂ . Then, at P10, pulse transmission is performed to realize the number of movement steps Si ₂ at P8 with this small pulse speed S ₂ (large driving force).

If YES in the determination in P7, it means that the target position Ikm has been realized by the small driving force of the step motor 21, so the process directly returns to P1 without passing through the route of P8 to P10.

Since the actual position detection accuracy of the position sensor 28 cannot be detected until the position change corresponding to the "one step" of the step motor 21, the actual position is detected in P7.
The deviation of Ik _{2 from} the target position Ikm is, for example, “5 steps”.
If it is within the range of, it is considered to be within the allowable error range.

Although the embodiments have been described above, the present invention is not limited to this, and includes the following cases.

A DC motor can also be used as an electric motor for drivingly displacing the control cam 36. In this case, the drive power of the DC motor may be adjusted by adjusting the supplied power (duty control can be performed temporarily by voltage adjustment).

When the control unit 25 is configured by using a computer, it may be either a digital type or an analog type. The control cam 36 may be a rotary type (in this case, the step motor 21 and the position sensor 28 are also rotary type). Should be used).

(Effects of the Invention) As is apparent from the above description, the present invention adjusts the driving force of the electric motor in response to the change in the driving force required to displace the control cam. The motor does not needlessly generate a large driving force. As a result, the drive displacement of the control cam, that is, the desired lubricating oil can be surely changed, and the durability of the electric motor can be ensured.

In particular, the position sensor that detects the actual position of the control cam is used to detect whether the driving force generated by the electric motor is sufficient or insufficient. Various factors that displace the required driving force can be dealt with comprehensively.

[Brief description of drawings]

FIG. 1 is an overall system diagram showing an embodiment of the present invention. FIG. 2 is a sectional view showing an example of a portion for measuring lubricating oil by a plunger. FIG. 3 is a sectional view taken along the line III-III in FIG. FIG. 4 is a sectional view taken along line IV-IV in FIG. FIG. 5 is a graph showing an example of the relationship between the position of the control cam and the amount of lubricating oil discharged. FIG. 6 is a graph showing the relationship between the pulse speed and the operating speed of the step motor. FIG. 7 is a graph showing the relationship between the pulse speed and the driving force of the step motor. FIG. 8 is a flowchart showing a control example of the present invention. FIG. 9 is an overall configuration diagram of the present invention. 12: Intake passage 16: Port lubrication nozzle 17: Direct lubrication nozzle 18: First lubrication oil supply passage 19: Second lubrication oil supply passage 20: Metering oil pump 21: Step motor (electric motor) 25: Control unit 26: Air flow meter 27: Revolution sensor 28: Position sensor 31: Pump housing 32, 33: Plunger 32d, 33i: Measuring chamber 36: Control cam

Claims (1)

[Claims] 1. A lubricating oil supply device for an engine, wherein a reciprocating stroke amount of a plunger for pumping lubricating oil to an engine is adjusted by a control cam with which the plunger abuts. An electric motor for displacing, an operating state detecting means for detecting an operating state of the engine, a target position determining means for determining a target position of the control cam according to the operating state of the engine, and the target position Drive control means for controlling the drive of the electric motor; position detection means for detecting the actual position of the control cam; deviation detection means for detecting the deviation between the target position and the actual position; and the electric motor When driving to reach the target position,
When a deviation occurs between the target position and the actual position,
A lubricating oil supply device for an engine, comprising: a driving force correcting means for increasing a driving force of the electric motor.