KR102560499B1 - Transmission for agricultural working machine with improved lubricating characteristic - Google Patents

Abstract

The present invention relates to a transmission for agricultural vehicles having improved lubricating characteristics, and more particularly, in a transmission for agricultural vehicles operating with a plurality of gears, by improving the lubricating characteristics of the gears, noise that may occur when the transmission is driven is reduced. It relates to a transmission for agricultural vehicles having improved lubrication characteristics capable of preventing and effectively suppressing a decrease in durability.
In the present invention, a plurality of gears including a first gear 110 and a second gear 120 meshed with and driven by the first gear 110 are provided, and the gear teeth of the first gear 110 ( 111) The gear lubrication index (LC = θ / FC) divided by the oil contact angle (θ) of the transmission oil formed on the surface by the friction coefficient (FC) of the surface of the gear teeth 111 ranges from 450 to 3000 Discloses a transmission 100 for agricultural vehicles, characterized in that in.

Description

Transmission for agricultural vehicles with improved lubrication characteristics {TRANSMISSION FOR AGRICULTURAL WORKING MACHINE WITH IMPROVED LUBRICATING CHARACTERISTIC}

The present invention relates to a transmission for agricultural vehicles having improved lubricating characteristics, and more particularly, in a transmission for agricultural vehicles operating with a plurality of gears, by improving the lubricating characteristics of the gears, noise that may occur when the transmission is driven is reduced. It relates to a transmission for agricultural vehicles having improved lubrication characteristics capable of preventing and effectively suppressing a decrease in durability.

In general, as shown in FIG. 1, in agricultural vehicles 1 such as tractors, combines, and rice transplanters, gear engagement is changed according to forward, backward or driving speed in order to transmit the output of the engine 20 to the driving wheels A transmission 100 is provided.

At this time, the transmission 100 provided in the agricultural work vehicle 1 is provided with a plurality of gears, and transmits the power of the engine 20 to the drive shaft while changing the gear ratio according to the setting.

However, in the transmission 100, noise, vibration, heat, etc. may be generated due to friction between gears while the gears are engaged and driven. In addition, the efficiency of the transmission 100 may decrease, and furthermore, wear of the gears may occur. As a result, the durability life of the transmission 100 may decrease.

In particular, the agricultural work vehicle 1 performs work in a work area by attaching various work machines according to the work to be performed. Compared to a general vehicle, the agricultural work vehicle 1 and the working machine attached thereto are not only heavy, but also due to high load work in the work area, the transmission 100 of the agricultural work vehicle generates noise, vibration, heat, etc. The larger the gear, the lower the efficiency, and the greater the wear of the gear, the shorter the durability. Accordingly, transmission oil is injected into the transmission 100 to lubricate the transmission ( The performance of the transmission 100 is improved by preventing generation of noise and reduction of efficiency in the 100).

However, in the prior art, simply injecting transmission oil into the transmission 100 to improve the performance of the transmission 100 through lubrication, specifically, the friction characteristics of the gear used in the transmission 100 or the transmission How can the operation characteristics of the transmission 100 be improved according to the characteristics of the oil, and more specifically, the durability life due to noise caused by friction in gears generated during operation of the transmission 100 or gear wear? No specific solution has been proposed on how to effectively suppress the decrease.

Accordingly, the transmission 100 does not stop at simply injecting the transmission oil into the transmission 100, but also improves the lubrication characteristics of the gear by considering the specific characteristics of the gear used in the transmission 100, transmission oil, etc. There is a demand for a method to more effectively improve performance such as noise or durability of the device, but an appropriate solution has not yet been presented.

Republic of Korea Patent Publication No. 10-2005-0006151 (2005.01.15)

The present invention has been made to solve the above problems, and by improving the lubrication characteristics of the gear in consideration of the characteristics of the gear, transmission oil, etc. used in the transmission 100 for the agricultural work vehicle, the transmission 100 for the agricultural work vehicle It is an object of the present invention to provide a transmission for an agricultural vehicle having improved lubrication characteristics that can more effectively improve performance such as noise or durability of the vehicle.

Other detailed objects of the present invention will be clearly identified and understood by experts or researchers in the art through the specific contents described below.

A transmission 100 for an agricultural vehicle according to an embodiment of the present invention for solving the above problems includes a first gear 110 and a second gear 120 meshed with and driven by the first gear 110 It has a plurality of gears including, and the oil contact angle (contact angle, θ) of the transmission oil formed on the surface of the gear teeth 111 of the first gear 110 is the friction coefficient of the surface of the gear teeth 111 ( It is characterized in that the gear lubrication index (LC = θ / FC) divided by FC) is in the range of 450 or more and 3000 or less.

At this time, the gear lubrication index (LC) may be a value calculated from the contact surface 112 contacting the second gear 120 at the gear teeth 111 of the first gear 110 .

In addition, when the first gear 110 is driven, the gear lubrication index (WLC) considering the load obtained by multiplying the contact area (A) of the gear tooth 111 with the second gear 120 by the gear lubrication index (LC) = A x LC) may be in the range of 470 or more and 2530 or less.

Also, the contact area (A) may be an area at a point of maximum contact with the second gear 120 during driving of the first gear 110 .

Also, the first gear 110 and the second gear 120 may be made of the same material.

In the transmission 100 for agricultural vehicles having improved lubrication characteristics according to an embodiment of the present invention, the gear lubrication index (LC) and the load in consideration of characteristics of gears, transmission oil, etc. used in the transmission 100 for agricultural vehicles By adjusting the gear lubrication index (WLC) to improve the lubrication characteristics of the transmission 100 for agricultural vehicles, it is possible to more effectively improve performance such as noise and durability of the transmission 100 for agricultural vehicles.

1 is an exemplary view of a typical agricultural work vehicle 1 .
2 is a view explaining an oil contact angle θ at gear teeth 111 of a first gear 110 in a transmission 100 for an agricultural work vehicle according to an embodiment of the present invention.
3 is a view explaining the contact area A of the first gear 110 and the second gear 120 in the transmission 100 for an agricultural work vehicle according to an embodiment of the present invention.
4 to 6 show a characteristic change of the transmission 100 for an agricultural work vehicle according to a gear lubrication index (LC) and a load-considering gear lubrication index (WLC) in the transmission 100 for an agricultural work vehicle according to an embodiment of the present invention. It is an explanatory drawing.

The present invention can apply various transformations and can have various embodiments. Hereinafter, specific embodiments will be described in detail based on the accompanying drawings.

The following examples are provided to facilitate a comprehensive understanding of the methods, apparatus and/or systems described herein. However, this is only an example and the present invention is not limited thereto.

In describing the embodiments of the present invention, if it is determined that the detailed description of the known technology related to the present invention may unnecessarily obscure the subject matter of the present invention, the detailed description will be omitted. In addition, terms to be described later are terms defined in consideration of functions in the present invention, which may vary according to the intention or custom of a user or operator. Therefore, the definition should be made based on the contents throughout this specification. Terms used in the detailed description are only for describing the embodiments of the present invention, and should not be limiting. Unless expressly used otherwise, singular forms of expression include plural forms. In this description, expressions such as “comprising” or “comprising of” are intended to indicate certain characteristics, numbers, steps, operations, elements, some or combinations thereof, and one or more other than those described. It should not be construed to exclude the existence or possibility of any other feature, number, step, operation, element, part or combination thereof.

In addition, terms such as first and second may be used to describe various components, but the components are not limited by the terms, and the terms are used for the purpose of distinguishing one component from another. used only as

Hereinafter, exemplary embodiments of a transmission (100, hereinafter abbreviated as 'transmission') for agricultural vehicles having improved lubrication characteristics according to the present invention will be described in detail with reference to the accompanying drawings.

First, the transmission 100 for agricultural vehicles having improved lubrication characteristics according to an embodiment of the present invention includes a first gear 110 and a second gear 120 meshed with and driven by the first gear 110. ), and the oil contact angle (θ) of the transmission oil formed on the surface of the gear teeth 111 of the first gear 110 is the friction coefficient of the surface of the gear teeth 111 It is characterized in that the gear lubrication index (LC = θ / FC) divided by (FC) is in the range of 450 or more and 3000 or less.

In contrast, FIG. 2 shows the oil contact angle θ at the gear teeth 111 of the first gear 110 in the transmission 100 according to an embodiment of the present invention.

As can be seen in Figure 2, in the transmission 100 for agricultural vehicles having improved lubrication characteristics according to an embodiment of the present invention, the first gear 110 includes a plurality of gear teeth 111 is provided If sufficient transmission oil is not applied to the surface of the gear tooth 111, noise and heat may be generated or durability of the gear 110 may be deteriorated while friction increases.

At this time, in FIG. 2, the oil contact angle θ is shown in detail by enlarging the first gear 110 and the surface portion of the gear tooth 111 of the first gear 110 (FIG. 2A), there is.

Referring to FIG. 2, in the present invention, the oil contact angle θ refers to the transmission oil on the surface of the gear teeth 111 of the first gear 110 included in the transmission 100. On the other hand, the tangent line at the contact point of the three phases (P in FIG. 2) of the gear tooth 111 as a solid, the transmission oil as a liquid, and the air as a gas and the solid Among the angles formed by the surface of the gear teeth 111, it means the angle on the side where the liquid (ie, the transmission oil) is located (θ in (A) of FIG. 2).

At this time, the oil contact angle θ is the viscosity of the mission oil, the material properties of the gear 110 (eg, surface roughness, lipophilicity of the material, etc.), temperature, and the surrounding atmosphere. etc. can be affected.

In addition, the friction coefficient (FC) of the gear teeth 111 may vary depending on the surface roughness, material, and shape of the gear teeth 111 .

At this time, the friction coefficient (FC) of the gear teeth 111 affects the generation of noise and heat during gear operation, and the smaller the friction coefficient (FC) is, the better, but when it becomes smaller than a certain level, the gear By causing gear slip, the efficiency of power transmission may be impaired.

Accordingly, in the transmission 100 for agricultural vehicles having improved lubrication characteristics according to an embodiment of the present invention, the gear lubrication coefficient (LC, Lubricating Coefficient) is the gear teeth 111 of the first gear 110. ) may be defined as a value obtained by dividing the oil contact angle (θ) of the transmission oil formed on the surface by the friction coefficient (FC) of the surface of the gear teeth 111 (LC = θ / FC).

More specifically, the gear lubrication index (LC) is preferably calculated from the contact surface 112 in contact with the second gear 120 at the gear teeth 111 of the first gear 110 .

At this time, if the gear lubrication index (LC) is too small, noise of the transmission 100 may increase due to friction in the gear teeth 111, and if the gear lubrication index (LC) is too large, gear slip ), etc., the efficiency of power transmission in the transmission 100 is lowered and the service life of the transmission 100 is reduced.

As can be seen in FIG. 4, the gear lubrication index (LC) according to the oil contact angle (θ) and the friction coefficient (FC) in various driving environments and the corresponding noise characteristics in the transmission 100 were calculated.

At this time, the data of FIG. 4 was calculated in an experimental environment with a test temperature of 23-27 degrees Celsius and an oil temperature of 50 degrees in a laboratory atmosphere using a dynamometer. At this time, the friction coefficient (FC) of the gear tooth 111 is Surface roughness can be adjusted through treatment or the like, or, in the case of the very low friction coefficient FC, it can be adjusted through surface nitriding treatment or the like.

In addition, in calculating the noise characteristics of the transmission 100, the number of revolutions (RPM) is 2000 cycles (where one cycle is when a small gear rotates once) under a load input condition of 80% compared to the rated torque (torque). set and calculated.

In FIG. 5, only the gear lubrication index (LC) according to the oil contact angle (θ) and friction coefficient (FC) in the various driving environments and noise characteristic data of the transmission 100 are extracted and arranged in the table of FIG. 4. did

As can be seen in FIG. 5 , when the gear lubrication index (LC) is in the range of 450 or more and 3000 or less, it can be seen that the noise characteristics of the transmission 100 can be remarkably improved.

More specifically, as can be seen in FIG. 5, when the gear lubrication index (LC) is less than 450, the noise characteristic of the transmission 100 is 78 to 87 dB, and the gear lubrication index (LC) is greater than 3000 In this case, it can be confirmed that the noise characteristics of the transmission 100 are in the range of 78 to 79 dB.

On the other hand, when the gear lubrication index (LC) is in the range of 450 or more and 3000 or less, the noise characteristics of the transmission 100 stop at 52 to 66 dB. know that it can be improved.

In addition, in the transmission 100 for agricultural vehicles having improved lubrication characteristics according to an embodiment of the present invention, the second gear 120 in the gear teeth 111 when the first gear 110 is driven It is characterized in that the load-considering gear lubrication index (WLC = A x LC) obtained by multiplying the contact area (A) with the gear lubrication index (LC) is in the range of 470 or more and 2530 or less.

In contrast, FIG. 3 illustrates the contact area A between the first gear 110 and the second gear 120 in the transmission 100 according to an embodiment of the present invention.

First, as can be seen in Figure 3, in the transmission 100 for agricultural vehicles having improved lubrication characteristics according to an embodiment of the present invention, the first gear 110 is geared to the second gear 120 combined and driven (FIG. 3(a)). At this time, the contact area between the gear teeth 111 of the first gear 110 and the gear teeth 121 of the second gear 120 is called the contact area (A). It is called (Fig. 3 (b)).

Furthermore, the contact area (A) is preferably an area at the point of maximum contact with the second gear 120 during driving of the first gear 110 .

At this time, the contact area (A) between the first gear 110 and the second gear 120 affects power transmission and heat generation of the transmission 100, and furthermore, due to a fretting wear phenomenon Noise generation and durability of the transmission 100 are also affected.

Furthermore, it is preferable that the first gear 110 and the second gear 120 are made of the same material.

In this case, when the first gear 110 and the second gear 120 are made of the same material, the friction coefficient FC of the first gear 110 and the second gear 120 and the The oil contact angle θ may have the same or similar value, and thus the gear lubrication index LC and the load-considering gear lubrication index WLC for not only the first gear 110 but also the second gear 120 ) can be adjusted identically or similarly, so that noise characteristics or durability characteristics of the transmission 100 can be more easily improved.

Accordingly, in the agricultural vehicle transmission 100 having improved lubricating characteristics according to an embodiment of the present invention, the weighted lubricating coefficient (WLC) is applied when the first gear 110 is driven. It may be defined as a value obtained by multiplying the contact area (A) of the gear tooth 111 with the second gear 120 by the gear lubrication index (LC) (WLC = A x LC).

At this time, if the load-considering gear lubrication index (WLC) is too small, an excessive load is applied to the contact surface between the gear teeth 111 and 112, thereby shortening the durability of the transmission 100, and the load-considering gear lubrication If the index WLC is too large, noise may be generated in the transmission 100 due to excessive contact between the gear teeth 111 and 112 .

As described above with respect to FIG. 4, in addition to the gear lubrication index (LC) according to the oil contact angle (θ) and the friction coefficient (FC) in various driving environments and the resulting noise characteristics in the transmission 100, the load consideration gear Lubrication index (WLC) and durability life characteristics were calculated accordingly.

At this time, the data of FIG. 4 was calculated in an experimental environment with a test temperature of 23-27 degrees Celsius and an oil temperature of 50 degrees in a laboratory atmosphere using a dynamometer. At this time, the friction coefficient (FC) of the gear tooth 111 is Surface roughness can be adjusted through treatment or the like, or, in the case of the very low friction coefficient FC, it can be adjusted through surface nitriding treatment or the like.

In addition, in calculating the durability life characteristics of the transmission 100, the number of rotations (RPM) is 150 cycles under a load input condition of 120% compared to the rated torque (torque) (where one cycle is when a small gear rotates once) It was calculated by setting

In FIG. 6, the load-considering gear lubrication index (WLC) according to the oil contact angle (θ), the friction coefficient (FC), and the gear lubrication index (LC) in the various driving environments in the table of FIG. 4 and the transmission 100 therefor Only the durability characteristics data from was extracted and organized.

As can be seen in FIG. 6 , when the load-considering gear lubrication index (WLC) is in the range of 470 or more and 2530 or less, it can be confirmed that the durability life characteristics of the transmission 100 can be remarkably improved.

More specifically, as can be seen in FIG. 6, when the load-considered gear lubrication index (WLC) is less than 470, the durability life characteristics of the transmission 100 are 56,872 to 411,500 cycles, and the load-considered gear lubrication index ( When WLC) is 2760 exceeding 2530, it can be confirmed that it is only about 72,003 cycles.

On the other hand, when the gear lubrication index (LC) is in the range of 470 or more and 2530 or less, the durability life characteristics of the transmission 100 are improved up to 1,620,430 to 2,000,000 cycles or more, compared to the above case. It can be seen that a significant improvement of about 4 times or more can be achieved.

Accordingly, in the transmission 100 for agricultural vehicles having improved lubrication characteristics according to an embodiment of the present invention, the gear lubrication index (LC) and the load in consideration of the characteristics of gears, transmission oil, etc. used in the transmission 100 By adjusting the gear lubrication index (WLC) to improve the lubrication characteristics of the transmission 100, the performance of the transmission 100, such as noise and durability, can be improved more effectively.

The above description is merely illustrative of the technical idea of the present invention, and various modifications, changes, and substitutions can be made by those skilled in the art within the scope of not departing from the essential characteristics of the present invention. It will be possible. Therefore, the embodiments disclosed in the present invention and the accompanying drawings are not intended to limit the technical idea of the present invention, but to explain, and the scope of the technical idea of the present invention is not limited by these embodiments and the accompanying drawings. . The protection scope of the present invention should be construed by the following claims, and all technical ideas within the equivalent range should be construed as being included in the scope of the present invention.

(1): agricultural work vehicle (20): engine
(100): transmission (110): first gear
(111): gear tooth (112): contact surface
(120): 2nd gear (121): gear teeth

Claims (5)

The first gear 110,
It has a plurality of gears, including a second gear 120 that is engaged with and driven by the first gear 110,
The gear lubrication index (LC = θ / FC) transmission 100 for agricultural vehicles, characterized in that in the range of 450 or more and 3000 or less. According to claim 1,
The gear lubrication index (LC) is a transmission for agricultural vehicles, characterized in that the value calculated from the contact surface 112 in contact with the second gear 120 in the gear teeth 111 of the first gear 110 ( 100). According to claim 1,
When the first gear 110 is driven, the gear lubrication index (WLC = A) obtained by multiplying the contact area (A) of the gear tooth 111 with the second gear 120 by the gear lubrication index (LC) A transmission (100) for an agricultural vehicle, characterized in that x LC) is in the range of 470 or more and 2530 or less. According to claim 3,
The contact area (A) is,
Transmission 100 for agricultural vehicles, characterized in that the area at the time of maximum contact with the second gear 120 during driving of the first gear 110. According to claim 1,
The first gear 110 and the second gear 120 are transmissions 100 for agricultural vehicles, characterized in that composed of the same material.