KR20150000945A - Engine for diesel vehicles - Google Patents

Abstract

An embodiment of the present invention relates to an engine for a diesel vehicle, which comprises a crankshaft for transmitting power, a crankcase for enclosing the crankshaft so that both ends of the crankshaft are protruded, and a crankcase for supporting both ends of the crankshaft, And an oil chamber having a lip portion formed on a surface contacting the crankshaft and having an inner surface of the lip portion formed with a helical groove increasing in number as it goes downward.

Description

{ENGINE FOR DIESEL VEHICLES}

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an engine, and more particularly, to an engine for a diesel vehicle that improves the sealing performance of the crankshaft and the oil chamber and prevents leakage of the driving oil filled in the crankcase.

Generally, an engine for a diesel vehicle is provided with a crankshaft for transmitting power. Specifically, the crankshaft is a device that converts the reciprocating motion into the rotational motion. Here, a crankcase is disposed for protecting the crankshaft and surrounding the crankshaft for smooth driving of the crankshaft.

The inside of the crankcase is filled with driving oil to help drive the crankshaft. At this time, an oil chamber is mounted between the crankshaft and the crankcase so that the drive oil filled in the crankcase does not leak to the outside.

In the conventional oil chamber, a lip portion is formed at a portion in contact with the crankshaft to improve the adhesion between the crankshaft and the oil chamber. In addition, although the rubber material and the polymer material having elasticity are used as the material of the oil chamber in which the lip portion is formed, there is a problem that the elasticity deteriorates and abrasion occurs due to deterioration.

In order to solve the above problems, PTFE (Polytetrafluoroethylene) material having excellent heat resistance, chemical resistance and low coefficient of friction is used, and in order to improve the followability to the eccentricity caused by the rotation of the crankshaft, An additional member such as an elastic member was added.

However, changing the material of the oil chamber and inserting the additional member has a problem of raising the manufacturing cost of the oil chamber.

Further, when the crankshaft is stopped after the high-speed rotation, the crankshaft is biased in one direction by the rotation of the crankshaft. As a result, a gap is formed between the crankshaft and the oil chamber, and the drive oil is leaked through the gap.

An embodiment of the present invention provides an engine for a diesel vehicle in which an inner surface of an oil chamber contacting a crankshaft is formed with a helical groove increasing in number as it goes downward.

According to embodiments of the present invention, there is provided a crankshaft comprising: a crankshaft for transmitting power; a crankcase enclosing the crankshaft such that both ends of the crankshaft are protruded; and a crankcase coupled between both ends of the crankshaft and the crankcase A lip portion formed on a surface contacting with the crankshaft, and an oil chamber formed on an inner surface of the lip portion, the helical groove increasing in number as it goes downward.

And the contact surface of the lip portion increases as it goes downward.

The minimum number of the helical grooves may be three or less.

The maximum number of the helical grooves may be 7 to 9 or less.

And an elastic member between the lower end of the oil chamber and the upper end of the crankcase.

According to embodiments of the present invention, an engine for a diesel vehicle has an effect of improving the sealing performance of the crankshaft and the oil chamber, thereby preventing leakage of the driving oil filled in the crankcase.

Further, since the shape of the oil chamber is not largely deformed and the leakage of the driving oil is prevented, the manufacturing cost is low compared with the performance of the oil chamber.

1 is an exploded perspective view of a diesel vehicle engine according to a first embodiment of the present invention.
Fig. 2 is a side perspective view of the oil chamber shown in Fig. 1. Fig.
3 is a partial cross-sectional view of the oil chamber shown in Fig.
4 is an assembled cross-sectional view of an engine for a diesel vehicle according to a second embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, which will be readily apparent to those skilled in the art to which the present invention pertains. The present invention may be embodied in many different forms and is not limited to the embodiments described herein.

The drawings are schematic and illustrate that they are not drawn to scale. The relative dimensions and ratios of the parts in the figures are shown exaggerated or reduced in size for clarity and convenience in the figures, and any dimensions are merely illustrative and not restrictive. And to the same structure, element or component appearing in more than one drawing, the same reference numerals are used to denote similar features.

The embodiments of the present invention specifically illustrate ideal embodiments of the present invention. As a result, various variations of the illustration are expected. Thus, the embodiment is not limited to any particular form of the depicted area, but includes modifications of the form, for example, by manufacture.

Hereinafter, an engine 101 for a diesel vehicle according to a first embodiment of the present invention will be described with reference to Figs. 1 and 3. Fig.

FIG. 1 is an exploded perspective view of an engine for a diesel vehicle according to a first embodiment of the present invention, and FIG. 2 is a side perspective view of the oil chamber shown in FIG. 3 is a partial cross-sectional view of the oil chamber shown in Fig.

1, the engine 101 for a diesel vehicle according to the first embodiment of the present invention includes a crankshaft 10, a crankcase 20, and an oil chamber 30. As shown in Fig.

A generally used crankshaft 10 according to the present invention is a device that is engaged with one end of a piston (not shown) disposed inside an engine 101 for a diesel vehicle to convert the reciprocating motion of the piston into rotational motion. In other words, the driving force generated by the engine is transmitted to the outside of the engine through the crankshaft 10.

Here, a crankcase 20 surrounding the crankshaft 10 is disposed so that both ends of the crankshaft 10 are projected. The inside of the crankcase 20 is filled with driving oil for smooth driving of the crankshaft 10. [ The oil chamber 30 is coupled between both ends of the crankshaft 10 and the crankcase 20 so as to prevent leakage of the driving oil filled in the crankcase 20.

The oil chamber 30 has a flange portion 32 and a lip portion 34 formed thereon. The flange portion 32 is in contact with both ends of the crankcase 20 and the lip portion 34 is arranged to surround the outer circumferential surface of the crankshaft 10.

Here, the contact surface of the lip portion 30 that contacts the crankshaft 10 increases in contact with the lower end of the crankshaft 10.

It is possible to prevent the drive oil from leaking to the outside of the crankcase 20 even if the contact surface of the lip portion 30 is excessively collected at the lower end portion of the crankshaft 10 as the contact surface increases toward the lower end portion of the crankshaft 10 can do.

A helical groove 36 is formed on the inner surface of the lip portion 34 to increase the adhesion between the oil chamber 30 and the crankshaft 10. It is preferable that the helical groove 36 is formed so as to have a shape and a gap corresponding to the thread formed on the outer peripheral surface of the crankshaft 10 in general.

The gap between the helical grooves 36 may vary according to the technician of the present invention. However, according to the first embodiment of the present invention, the gap between the helical grooves 36 is preferably formed to have a constant gap. This has the effect of increasing the workability of the oil chamber 30 and reducing the manufacturing cost.

The crankshaft 10 is brought into close contact with the crankshaft 10 by the helical groove 36 formed on the inner surface of the lip portion 34 so that the drive oil is pumped into the crankshaft 10 when the crankshaft 10 rotates. So that leakage of the driving oil can be prevented.

At this time, it is important to determine the number of the helical grooves 36. The number of the spiral grooves 36 formed in the lip portion 34 is also increased as the area of the lip portion 34 contacting the crankshaft 10 increases toward the lower portion about the axis of the crankshaft 10 as described above, It is preferable that the number of the helical grooves 36 increases from the upper portion to the lower portion with respect to the axis of the rotor 10.

Although not limited thereto, the minimum number of the helical grooves 36 of the lip portion 34 according to the first embodiment of the present invention is preferably 3 to 5 or less.

Specifically, when the crankshaft 10 rotates, the drive oil is introduced into the crankcase 20 along the spiral groove 36 of the oil chamber 30. As shown in Fig. That is, when the crankshaft 10 rotates, the first and second helical grooves 36 formed close to the inside of the crankcase 20 have drive oil, so that the spiral of the crankshaft 10 and the oil chamber 30 can be sealed in the fourth or fifth helical groove 36 even if the drive oil flows to the third helical groove 36 due to clogging or abrasion.

Also, although not limited thereto, the maximum number of the helical grooves 36 of the lip portion 34 according to the first embodiment of the present invention is preferably 7 to 9. If the maximum number of the helical grooves 36 is larger than 9, it is difficult to process the oil chamber 30 itself, and thus the manufacturing cost of the oil chamber 30 increases.

In order to verify the effect of reducing oil leakage in the oil chamber 30 formed asymmetrically with the upper and lower areas according to the first embodiment of the present invention, A test was conducted to measure the leakage amount of the driving oil for 200 hours (hr).

The minimum number of the helical grooves 36 formed in the lip portion 34 is fixed to four as shown in Table 1 because the minimum number of the helical grooves 36 is 4 or more as described above, This is because the drive oil is not leaked in close contact with the shaft 10 and the oil chamber 30. The reason why the maximum number of the helical grooves 36 is fixed to eight is that the workability is easy when the maximum number of the helical grooves 36 is an even multiple.

In the leak test of the three specimens in Table 1, the temperature of the driving oil, the eccentricity of the crankshaft (10), and the internal pressure conditions, which can directly cause the oil leakage, were selected. Respectively.

The reason why the eccentricity of the crankshaft 10 is set as the test condition is that the center of the crankshaft 10 and the oil chamber 30 are deformed due to the machining and assembling tolerances of the crankshaft 10 and the oil chamber 30. [ There is always a concentricity error between the centers. When the crankshaft 10 rotates, it is in close contact with the oil chamber 30. However, when the crankshaft 10 is stopped after rotation, the crankshaft 10 stops in one direction due to the eccentricity of the crankshaft 10, And the eccentricity of the rotor 10.

In addition, since the crankshaft 10, the crankcase 20, and the oil chamber 30 are all formed of a material influenced by metal and temperature, the temperature of the direct contact oil must be set as the condition.

Tests were conducted based on the above conditions, and the results were as shown in the following table.

Table 2 shows test results using four oil chambers 30 having symmetric structures, and Table 3 shows the results of the tests using the oil chambers 30 of the four symmetric structures. Table 4 shows the results of the tests using the oil chambers 30 formed with eight symmetric structures, respectively.

As shown in Table 2, the driving oil leakage flow rate in Example 1 was 0.190 (g / hr) on average. However, as shown in [Table 3] and [Table 4], in the case of Examples 2 and 3 in Table 1, when the crankshaft 10 was stopped, the leakage amounts of the drive oil were 0.060 (g / ) And an average value of 0.057 (g / hr), it was found that the leakage amount of the driving oil was reduced by about 70% as compared with Example 1 of [Table 1]. Also, when the crankshaft 10 rotates, the leakage amount of the driving oil is decreased.

As shown in [Table 3] and [Table 4], the leakage amounts of the driving oil in Examples 2 and 3, which are the two specimens of Table 1, were 0.060 (g / hr) and 0.057 (g / ). This means that the oil leakage of the drive oil can be reduced by increasing only the contact surface of the lip portion 34 contacting the lower end portion of the crankshaft 10 without increasing the overall contact surface of the lip portion 34 of the oil chamber 30 .

However, the structure of the second embodiment having the asymmetric spiral groove 36 having the asymmetric shape of the lip portion 34 and the minimum and maximum numbers of the asymmetric shape differs from that of the first embodiment, Compared to the third embodiment, the friction generated from the contact surface of the lip portion 34 that contacts the crankshaft 10 has a small loss, and the manufacturing cost of the oil chamber 30 itself can be reduced.

Therefore, according to the first embodiment of the present invention, the area of the lip portion 34 of the oil chamber 30 of the engine 101 for a diesel vehicle becomes larger toward the lower end portion of the crankshaft 10, It is preferable to form the oil chamber 30 having the asymmetric lip portion 34 formed so as to increase the number of the helical grooves 36 that are formed in the oil groove.

The oil chamber 30 having an asymmetric structure in which the number and the area of the helical grooves 36 increases toward the lower portion of the engine 101 for a diesel vehicle is disposed between the crankshaft 10 and the crankcase 20 The leakage of the driving oil between the crankshaft 10 and the crankcase 20 can be prevented.

Further, leakage of the drive oil can be prevented without largely deforming the shape of the oil chamber (30), thereby reducing the manufacturing cost of the oil chamber (30).

4 is an assembled cross-sectional view of an engine for a diesel vehicle according to a second embodiment of the present invention.

As shown in Fig. 4, the engine 102 for a diesel vehicle further includes an elastic member 40. Fig.

Specifically, the followability of the oil chamber 30 is lowered by the rotation of the crankshaft 10, and the drive oil filled in the crankcase 20 is leaked. Particularly, when the crankshaft 10 is stopped, leakage occurs between the lower end of the crankshaft 10 and the oil chamber 30. The elastic member 40 is disposed between the lower end portion of the oil chamber 30 and the upper end portion of the crankcase 20 in order to improve the followability of the oil chamber 30 and prevent leakage of the drive oil .

The elastic member 40 according to the second embodiment of the present invention may be various types of resilient members known to those of ordinary skill in the art, and it is preferable that compression springs are disposed, though not necessarily limited thereto.

The elastic members 40 may be arranged in one or more than one, and the shape and size of the arranged spring may vary according to the ordinary artisan of practicing the present invention.

The diesel engine 102 prevents the elastic member 40 from supporting the crankshaft 10 so that the crankshaft 10 is not tilted in one direction due to eccentricity caused by rotation. As a result, no gap is formed between the crankshaft 10 and the oil chamber 30, so that leakage of the driving oil in the crankcase 20 can be prevented.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. will be.

It is therefore to be understood that the embodiments described above are to be considered in all respects only as illustrative and not restrictive, the scope of the invention being indicated by the appended claims, It is intended that all changes and modifications derived from the equivalent concept be included within the scope of the present invention.

101, 102: Engine for diesel vehicles
10: crankshaft 20: crankcase
30: oil chamber 32: flange portion
34: Lip portion 36: Spiral groove
40: elastic member

Claims (5)

A crankshaft 10 for transmitting power;
A crankcase 20 surrounding the crankshaft 10 such that both ends of the crankshaft 10 are protruded; And
A lip portion 34 is formed on a surface contacting with the crankshaft 10 and formed on the inner surface of the lip portion 34 so as to be engaged with the lower portion of the crankshaft 10, The oil chamber 30 in which the helical groove 36 whose number increases as it goes to the oil chamber 30 is formed,
The engine for a diesel vehicle. The method according to claim 1,
Wherein a contact surface of the lip portion (34) increases as it goes down. 3. The method according to claim 1 or 2,
Wherein the minimum number of the helical grooves (36) is three to five or less. 3. The method according to claim 1 or 2,
And the maximum number of the helical grooves (36) is set to 7 to 9 or less. 3. The method according to claim 1 or 2,
Further comprising an elastic member (40) between a lower end of the oil chamber (30) and an upper end of the crankcase (20).

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