JPH116414A - Engine with oil level detector - Google Patents

Abstract

(57) [Problem] To prevent the occurrence of a malfunction that the engine cannot be started when the engine is started after supplying lubricating oil to the crankcase of the engine. SOLUTION: A float housing chamber 4 is formed in a casing 2, lubricating oil in a crank chamber 8 flows into the float housing chamber 4 from an oil inlet 14, and air in the float housing chamber 4 is vented from an air vent pipe 22. The air vent passage 19 is formed so as to pass through the port 18, and the air vent port 18 protrudes upward beyond the position of the lubricating oil full oil level 17 in the space 8. With this configuration, all the air in the float storage chamber 4 is evacuated before the air vent 18 of the float storage chamber 4 is immersed in the lubricating oil due to the rise of the lubricating oil in the crank chamber 8 during lubricating oil supply. Therefore, the occurrence of the malfunction can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine provided with an oil level detecting device, and more particularly to an engine provided with an oil level detecting device capable of preventing occurrence of malfunction.

[0002]

2. Description of the Related Art As an oil level detecting device for an engine, for example, an oil level detecting device 6 as shown in FIG.
2 are known. In FIG. 5, a mounting hole 65 for an oil level detecting device 62 is opened in a bottom wall 64 of a crank chamber 63 of the engine 61. The main body casing 66 of the oil level detecting device 62 is inserted into the mounting hole 65 and is fixed to the bottom wall 64 by a mounting bolt 67.

FIG. 6A is a front view of the conventional oil level detecting device, and FIG. 6B is a partial longitudinal sectional view thereof. As shown in FIG. 6B, the oil level detecting device 62 has a float housing chamber 68 formed in a cylindrical main body casing 66. The oil in the crank chamber 63 flows into the float housing chamber 68 from four oil inlets 69 (only two oil inlets 69 appear in FIG. 6A). Accommodates an annular float 70. The peripheral wall 72 near the upper wall 71 of the float accommodation room 68
Has four air vents 73 (only two appear in FIG. 6 (A)), and the four air vents 73 allow the air in the float housing chamber 68 to escape. I have.

The float 70 is provided with a lubricating oil from an oil inlet 69 corresponding to the level of the lubricating oil in a crank chamber 63 of the engine 61 (see FIG. 5).
The position of the float 70 is changed by flowing into the inside. A switch unit 75 (see FIG. 6B) for stopping the engine 61 when the reference position of the float 70 becomes lower than the lower limit oil level 74 is provided. When the lubricating oil level is lower than the lower limit oil level 74, which is the lower limit position, the switch section 75 is turned on, and the ignition circuit of the engine 61 is grounded via a control circuit (not shown) to stop the engine. It is configured in.

Therefore, when the lubricating oil in the crank chamber 63 is lower than the lower oil level 74 or lower than the lower oil level 74 during the operation of the engine or at the start of operation, the switch unit 75 is used. The engine can be brought into a stopped state or an unstartable state. In the above operation, when the air vent 73 is enlarged,
Since the air in the float storage chamber 68 escapes quickly, the float 70 in the float storage chamber 68 rises without delay with the rise in the level of the lubricating oil in the crank chamber 63. Also, if the air vent 73 is narrowed down, the air in the float chamber 68 becomes difficult to escape, and exists as an air pocket within a certain time width.
The effect as a damper that suppresses a minute movement of the float 70 due to the fluctuation of the lubricating oil level in the inside can be provided.

[0006]

As shown in FIG. 5,
The oil level detector 62 is connected to the bottom wall 64 of the crank chamber 63.
In this configuration, maintenance of the oil level detection device 62 is easy, but the oil level detection device 62 is easily affected by fluctuations in the oil level of the lubricating oil, and has the following problems. (1) First, when the air vent 73 shown in FIG. 6 is enlarged,
There is a disadvantage that the damper effect due to the air reservoir 76 in the upper part of the float housing chamber 68 is lost, and the fluctuation of the lubricating oil level appears in the vertical movement of the float 70 as it is. When such a vertical movement of the float 70 occurs near the lower limit oil level 74, a phenomenon (hereinafter, referred to as a chattering phenomenon) in which the switch unit 75 is repeatedly turned on and off is caused. That is, when the lubricating oil consumption decreases during the operation of the engine and the oil level of the lubricating oil reaches the position of the lower limit oil level 74, the switch unit 75 operates to stop the engine. Accordingly, if the lubricating oil raised in the cylinder block and the cylinder head returns to the crank chamber 63 and the float 70 rises above the lower limit oil level 74 again, the engine is restarted. Therefore, once a stop signal is input to the control circuit of the oil level detecting device 62, it is necessary to provide a self-holding circuit for maintaining the engine stopped state in the control circuit until the engine is completely stopped, resulting in an increase in cost. There's a problem.

(2) To solve the above problem, if the air vent 73 is narrowed down, the damper effect by the air reservoir 76 in the upper part of the float chamber 68 is strengthened as described above, and the float 70 causing chattering phenomenon is generated. Can be suppressed. However, when the air vent 73 is narrowed down, the following problem newly occurs. When the engine is started after supplying the lubricating oil into the crank chamber 63 in order to increase the lubricating oil that has been reduced, the air vent 73
The lubricating oil reaches the position of the full oil level 77 over the upper wall 71 of the oil level detecting device 62 before the air in the float accommodating chamber 68 escapes from the air. In this case, if the air vent 73 is narrowed down, the viscosity of the lubricating oil is high, so that it takes a considerable time for the air accumulated in the air reservoir 76 in the upper part of the float housing chamber 68 to completely escape from the air vent 73. . In this state, the float 70 cannot move upward beyond the switch operating position 74 due to the air accumulated in the air reservoir 76, so that there is a problem that the engine cannot be started even if the engine is started.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide an engine having an oil level detecting device which can solve the above problems. An example of a specific purpose is as follows. (a) The chattering phenomenon can be prevented from occurring when the oil level of the lubricating oil reaches the lower limit oil level during operation of the engine. (b) To solve the problem that the engine cannot be started when the engine is started after supplying the lubricating oil to the crankcase of the engine. (c) The operating level of the oil level detecting device is made substantially constant under all operating conditions, so that accurate operation of the oil level detecting device can be ensured. It should be noted that problems of the invention other than those described above and means for solving the problems will be described in detail in the section of means for solving the problems described below and the section of the embodiment of the invention.

[0009]

Means for Solving the Problems The first invention is, for example,
Explaining with reference to FIGS. 1 to 4, in an engine including an oil level detection device 1 for detecting a level of an oil level of lubricating oil in a crank chamber 8 of an engine 7, the oil level detection device 1 Float storage chamber 4 in casing 2
And the float accommodating chamber 4 is provided with an oil inlet 14
The lubricating oil in the crank chamber 8 flows in more, and the air in the float housing chamber 4 is configured to escape from the air vent 18 of the air vent passage 19, and the float 12 is housed in the float housing chamber 4. Corresponds to the height of the lubricating oil entering from the oil inlet 14 and the float 12
And a switch section 26 for stopping the engine 7 when the reference position of the float 12 becomes lower than the lower limit oil level 25. Further, the air vent passage 19 is The lubricating oil is extended upward by a predetermined length toward the upper part of the crank chamber 8, and floats before the air vent 18 of the air vent passage 19 is immersed in the lubricating oil due to the rise of the lubricating oil in the crank chamber 8 when lubricating oil is supplied. The predetermined length is set so that air in the chamber 4 escapes.

In the first aspect of the present invention, the air vent 18 can protrude upward beyond the predetermined length of the air vent passage 19 beyond the position of the lubricating oil level 17 in the crankcase chamber 8. When the length is set, the most reliable configuration for the air bleeding action in the float storage chamber 4 is obtained. The second invention will be described with reference to, for example, FIGS. 1 to 4. In the case where the first invention is applied to an engine including an oil depper 15 for spraying lubricating oil stored in a crank chamber 8. , The oil inlet 14 is opened in the wall of the casing 2 on the side where the oil depper 15 is located. In the configuration of the second aspect, it is preferable that a plurality of such oil inlets 14 are provided,
The oil inlets 14 are preferably arranged symmetrically with respect to a predetermined line (such as the center line 16 shown in FIG. 2) and a predetermined point. The third invention will be described with reference to FIGS. 1 to 4, for example, in which the air vent passage 19 is constituted by an air vent pipe 22 attached to an upper wall 20 of the casing 2.

[0011]

According to the first aspect of the present invention, when the lubricating oil is supplied, the lubricating oil in the crank chamber 8 rises to supply air to the air vent passage 19.
A predetermined length of the air vent passage 19 is set so that the air in the float accommodating chamber 4 escapes before the air vent 18 is immersed in the lubricating oil. Even when lubricating oil is supplied into the crank chamber 8 before the engine is started, the lubricating oil in the crank chamber 8 rises, so that the air vent port 18 of the float accommodating chamber 4 has the lubricating oil. Before immersion in the air, the air in the float storage chamber 4 can be evacuated. Therefore, when lubricating oil is supplied to the crankcase 8 of the engine, the position of the float 12 immediately moves to a position where the engine can be started, so that an erroneous operation in which the engine cannot be started after lubricating oil is supplied can be prevented.

According to the second aspect of the present invention, since the oil inlet 14 is opened in the wall of the casing 2 on the side where the oil depper 15 is located, the oil inlet is provided in the wall of the casing 2 on the side opposite to the side where the oil depper 15 is located. The operation level of the oil level detection device 1 can be made substantially the same under all operating conditions (especially, a change in rotation speed), as compared with the configuration in which the openings are formed. In the third aspect, the air vent passage 1
9 is constituted by the air vent pipe 22 attached to the upper wall 20 of the casing 2, so that the present invention can be easily implemented without changing the basic configuration of the conventional oil level detecting device, and the manufacturing cost is reduced. it can.

[0013]

According to the first aspect of the present invention, there is a special effect that a malfunction such that the engine cannot be started when the engine is started after supplying the lubricating oil to the crankcase of the engine can be prevented. If it is the second invention,
There is a specific effect that the operation level of the oil level detecting device can be made substantially constant under all operating conditions, and accurate operation of the oil level detecting device can be ensured. According to the third aspect, the present invention can be implemented without changing the basic configuration of a conventional oil level detecting device, and has a specific effect that the manufacturing cost can be reduced.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. FIG. 1A is a partial longitudinal sectional view for explaining an oil level detecting device according to the present invention, FIG. 1B is a plan view of the oil level detecting device, and FIG. II
FIG. 3A is a partially longitudinal side view of an engine provided with an oil level detecting device, and FIG. 3B is a partially longitudinal front view of the engine.

As shown in FIGS. 1 (A) and 1 (B), this oil level detecting device 1 has a ring-shaped cylindrical float 3 with a small-diameter central pipe 3 erected in a cylindrical casing 2. An accommodation chamber 4 is formed. The cylindrical casing 2 is fixed to a substantially rhombus-shaped mounting flange 5, and an O-ring 6 is provided at a connection position between the casing 2 and the mounting flange 5. In use, the crankcase 8 of the engine 7 (see FIG. 3)
The casing 2 is inserted into a mounting opening 10 provided in a bottom wall 9 of the crankcase 8, the airtightness is secured by an O-ring 6, and a bolt hole 11 of a mounting flange 5 shown in FIG.
To the bottom wall 9.

An annular float 12 is accommodated in the float accommodating chamber 4 so as to fit on the center circular tube 3. The lower peripheral wall 13 of the casing 2 is provided with two oil inlets 14 so as to communicate with the float storage chamber 4 as shown in FIG. As shown in FIG. 2, the oil inlet 14 is opened at a position symmetrical with respect to the center line 16 of the casing 2 when viewed from the peripheral wall 13 of the casing 2 on the side where the oil depper 15 is located.

As shown in FIG. 1 (A), the upper region of the float storage chamber 4 communicates with the float storage chamber 4 and the oil when the lubricating oil in the crank chamber 8 is full. An air vent passage 19 provided with an air vent 18 at a position higher than the surface (hereinafter referred to as a full oil level 17). In the embodiment shown in FIGS.
Is constructed by inserting an air vent pipe 22 into a pipe mounting opening 21 provided in the upper wall 20 of the casing 2 and positioning the air vent port 18 of the air vent pipe 22 above the full oil level 17. . As shown in FIG. 1 (A), a magnet 23 is attached to an upper position on the inner wall of the float 12 which is in contact with the central circular pipe 3, and the float 12 moves up and down by lubricating oil flowing from an oil inlet 14. So that the position of the magnet 23 is also raised and lowered. Note that the position of the magnet 23 functions as the reference position of the float 12.

The magnet 2 is provided in the central circular tube 3.
A magnetic switch 24 for stopping the operation of the engine when the position 3 becomes lower than the lower limit oil level 25 of the lubricating oil in the crank chamber is accommodated. The switch section 26 is constituted by the magnet 23 and the magnetic switch 24. When the oil level of the lubricating oil in the crank chamber 8 decreases due to the consumption of the lubricating oil or the like, the position of the float 12 in the float accommodating chamber 4 also lowers, and the magnet 23 activates the magnetic force switch 24 and the engine 23 , The position of the magnet in the float 12 and the position of the magnetic force switch 24 in the central circular tube 3 are respectively set.

Next, the arrangement of the oil level detecting device in the crank chamber of the engine will be described with reference to FIG. As shown in FIG. 3A, the oil level detecting device 1
The engine 7 is disposed near the flywheel 27 side of the crank chamber 8 and is disposed between the flywheel mounting side wall 29 of the cylinder block and the oil depper 15 projecting downward from the large end 30 of the connecting rod. I have.
Further, when the crankcase 8 is viewed from the crankcase cover 31 side, the oil level detecting device 1 is disposed substantially at the center of the crankcase 8 as shown in FIG. The governor gear 32 is disposed at the lower right position.

The operation of the oil level detecting device having the above configuration will be briefly described. First, the operation when lubricating oil is supplied to the crank chamber 8 of the engine 7 will be described.
In FIG. 1, when lubricating oil is supplied from an oil supply port (not shown) to the crank chamber 8, the lubricating oil is supplied from the two oil inlets 14 of the oil level detecting device 1 to the float housing chamber 4.
And the float 12 is pushed up. At this time, the air above the position where the float 12 is located in the float accommodating chamber 4 hinders the rise of the float 12 because the air vent port 18 of the air vent pipe 22 is located above the full oil level 17. It is discharged promptly without. Therefore, the problem that the oil level detecting device 1 stops the engine and the engine cannot be started at the time of the engine start operation as in the related art is eliminated.

Further, since the air vent passage 19 is provided as described above, it is not necessary to consider the problem that the engine cannot be started after replenishing the lubricating oil. Therefore, the air vent port 18 of the air vent passage 19 is reduced to a diameter of about 2 mm. Becomes possible. Therefore, a chattering phenomenon does not occur when the engine stops, unlike the configuration in which the air vent 18 is set large without providing the air vent passage 19. In addition, since the oil inlet 14 is arranged on the wall of the casing 2 on the side where the oil depper 15 is located, it is possible to suppress the fluctuation of the float 12 which becomes noise during engine operating conditions. This is for unknown reasons, but probably for the following reasons:

As shown in FIG. 4, on the peripheral wall 13 of the casing 2 on the side where the oil depper 15 is located, a push-up amount 34 caused by the scraping operation of the oil depper 15 and the oil depper 1
Inflow 3 due to the recess 35 in the oil surface of the scraped portion 3
6, two lubricating oil flows are generated. Here, considering a configuration in which an oil inflow port 37 is opened in the casing peripheral wall 13 on the opposite side to the oil depper 15, the push-up portion 34 is hardly affected by the casing 2 itself as a barrier at that position. Only the effect of the inflow 36 increases. Therefore, in the configuration in which the oil inlet 37 is opened, the fluctuation 38 of the lubricating oil level caused by the change in the oil scraping amount caused by the change in the rotation speed of the engine directly affects the movement of the float 12, and exists in the crank chamber 8. When the amount of lubricating oil to be detected is detected, the detection becomes inaccurate. That is, as the rotational speed increases, the amount of lubricating oil present in the crankcase 8 decreases. However, this is a normal operation of the engine, and it is not possible to detect the oil level including such a change in the rotational speed. It is contrary to purpose.

On the other hand, when the oil inlet 14 is arranged on the wall of the casing 2 on the side where the oil depper 15 is located, the amount of the push-up portion 34 due to the scraping operation of the oil depper 15 and the amount of the inflow portion 36 due to the recess 35 are substantially the same. And both are offset. Therefore, the position of the oil level at the oil inlet 14 does not significantly change regardless of the engine speed. As a result, the influence of the amount of lubricating oil scraped by the engine speed is reduced, and the amount of lubricating oil originally present in the crank chamber can be accurately detected in consideration of the amount of lubricating oil scraped. By providing a plurality of oil inlets 14 line-symmetrically and point-symmetrically on the wall of the casing 2 having the oil depper 15, the stability of the detection is improved.

The present invention is not limited to the above embodiment, and various design changes can be made without departing from the spirit of the present invention. Hereinafter, such an embodiment will be described. (1) In the above embodiment, the air vent passage 19 is constituted by the air vent pipe 22, but the upper portion of the float accommodating chamber 4 is formed to extend, and the air vent passage 19 integrated with the casing 2 is formed.
May be configured. Further, the configuration of the switch section 26 is not limited to the combination of the magnet 23 and the magnetic switch 24, and various switch means can be configured. (2) Further, in the above-described embodiment, the vertical engine has been described as an example. However, since it is necessary to detect the level of the lubricating oil in the crank chamber 8 even in a horizontal engine or an inclined engine,
It is clear that applications are possible as well.

[Brief description of the drawings]

FIG. 1A is a partial longitudinal sectional view illustrating an oil level detecting device according to the present invention, and FIG. 1B is a plan view of the oil level detecting device.

FIG. 2 is a view taken on line II-II of FIG. 1 (A).

FIG. 3A is a partially longitudinal side view of an engine provided with an oil level detecting device, and FIG. 3B is a partially longitudinal front view of the engine.

FIG. 4 is a view for explaining an effect of disposing an oil inflow port on a surface of the casing on a side having an oil depper;

FIG. 5 is a schematic diagram for explaining a mounting structure of the oil level detection device.

FIG. 6A is a front view of a conventional oil level detecting device, and FIG. 6B is a partial longitudinal sectional view thereof.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Oil level detection device, 2 ... Casing, 4 ... Float accommodation room, 7 ... Engine, 8 ... Crank room, 12 ... Float, 14 ... Oil inlet, 15 ... Oil depper, 1
8 ... air vent, 19 ... air vent passage, 20 ... upper wall, 2
2 ... air vent pipe, 25 ... lower limit oil level, 26 ... switch part.

Claims (3)

[Claims] An oil level detecting device (1) for detecting a level of a lubricating oil level in a crank chamber (8) of an engine (7).
The oil level detecting device (1) is provided with a float storage chamber (4) in a casing (2), and the float storage chamber (4)
(4) lubricating oil in the crank chamber (8) flows in from the oil inlet (14), and the air in the float accommodating chamber (4) is removed from the air vent passage.
It is configured to escape from the air vent (18) of (19), and accommodates the float (12) in the float accommodating chamber (4),
The float (12) is configured so that the position of the float (12) changes according to the height of the lubricating oil entered from the oil inlet (14), and the reference position of the float (12) is changed. When the oil level is lower than the lower limit (25), the engine (7)
The air vent passage (19) extends a predetermined length toward the upper part of the crank chamber (8). Before the air vent (18) of the air vent passage (19) is immersed in the lubricating oil due to the rise of the lubricating oil in (8),
An engine provided with an oil level detection device, wherein the predetermined length is set so that air in the float storage chamber (4) escapes. 2. In a case where the engine is provided with an oil depper (15) for spraying lubricating oil stored in a crank chamber (8), the lubricating oil may be sprayed on a wall of the casing (2) on a side where the oil depper (15) is located. Opened the oil inlet (14),
An engine provided with the oil level detection device according to claim 1. 3. The air vent passage (19) has a casing.
(2) Air vent pipe (2) attached to the upper wall (20)
An engine provided with the oil level detecting device according to any one of claims 1 and 2, wherein the engine is configured as in (2).