阅读说明：本技术 一种齿轮系及发动机 (Gear train and engine ) 是由 刘井年 李扬 张志权 杨立云 于 2019-09-19 设计创作，主要内容包括：本发明属于车辆技术领域,公开了一种齿轮系及发动机。该齿轮系,包括相互啮合的曲轴齿轮和凸轮轴齿轮；支撑轴,其凸设于凸轮轴齿轮上；外层齿轮,外层齿轮套设于支撑轴上并能够相对其转动；水泵驱动齿轮,其啮合于外层齿轮；曲轴齿轮被配置为驱动凸轮轴齿轮转动,并通过外层齿轮带动水泵驱动齿轮转动。该齿轮系实现曲轴齿轮-外层齿轮-水泵驱动齿轮的扭矩传递,外层齿轮可以绕着支撑轴旋转,外层齿轮与凸轮轴齿轮两者处于自由松动状态,不会传递冲击载荷,避免凸轮轴齿轮将冲击转速波动传递给外层齿轮,解决了水泵驱动齿轮转速波动大的问题,保证水泵驱动齿轮传动平稳性,从而降低水泵轴承和水封故障率,延长了使用寿命。(The invention belongs to the technical field of vehicles and discloses a gear train and an engine. The gear train comprises a crankshaft gear and a camshaft gear which are meshed with each other; the supporting shaft is convexly arranged on the cam shaft gear; the outer gear is sleeved on the support shaft and can rotate relative to the support shaft; a water pump driving gear meshed with the outer gear; the crankshaft gear is configured to drive the camshaft gear to rotate, and the water pump driving gear is driven to rotate through the outer layer gear. The gear train realizes torque transmission of the crankshaft gear, the outer gear and the water pump driving gear, the outer gear can rotate around the supporting shaft, the outer gear and the camshaft gear are in a free loosening state, impact load can not be transmitted, the camshaft gear is prevented from transmitting impact rotation speed fluctuation to the outer gear, the problem that the rotation speed fluctuation of the water pump driving gear is large is solved, and the transmission stability of the water pump driving gear is ensured, so that the fault rate of a water pump bearing and a water seal is reduced, and the service life is prolonged.)

1. A gear train comprising a crankshaft gear (1) and a camshaft gear (2) in mesh with each other, characterized by further comprising:

the supporting shaft (3) is arranged on the camshaft gear (2) in a protruding mode;

the outer-layer gear (4) is sleeved on the supporting shaft (3) and can rotate relative to the supporting shaft;

a water pump driving gear (5) meshed with the outer layer gear (4);

the crankshaft gear (1) is configured to drive the camshaft gear (2) to rotate, and the water pump driving gear (5) is driven to rotate through the outer layer gear (4).

2. Gear train according to claim 1, characterized in that an axial clearance is present between the outer gear (4) and the camshaft gear (2).

3. Gear train according to claim 1, wherein a radial clearance is present between the outer gear wheel (4) and the support shaft (3).

4. Gear train according to claim 3, characterized in that the radial gap is filled with pressure oil for lubrication between the outer gear (4) and the support shaft (3).

5. Gear train according to claim 1, further comprising a camshaft (6) and an intermediate gear (7), the camshaft gear (2) and the intermediate gear (7) being coaxially sleeved on the camshaft (6).

6. Gear train according to claim 5, characterized in that it further comprises a high pressure oil pump drive gear (8), said high pressure oil pump drive gear (8) being meshed with said intermediate gear (7).

7. Gear train according to claim 5, characterized in that the intermediate gear (7) and the camshaft gear (2) are connected by means of bolts.

8. Gear train according to claim 1, wherein the outer gear (4) has a central hole (41) opened therein, and the support shaft (3) is inserted into the central hole (41).

9. Gear train according to claim 8, characterized in that it further comprises a cover plate (9), said cover plate (9) being located on one side of said support shaft (3) and being arranged within said central hole (41).

10. An engine comprising a gear train according to any one of claims 1 to 9.

Technical Field

The invention relates to the technical field of vehicles, in particular to a gear train and an engine.

Background

As shown in fig. 1, in a conventional engine gear train, a crankshaft gear 100 drives a camshaft gear 200 to rotate, and the camshaft gear 200 drives a camshaft 300 to drive an intake valve and an exhaust valve to open and close, so that an impact force applied to the camshaft 300 is large. The camshaft gear 200 and the intermediate gear 400 are rigidly fixed by bolts, so that the camshaft gear 200 drives the water pump driving gear 500 to rotate, and meanwhile, the intermediate gear 400 drives the high-pressure oil pump driving gear 600 to rotate.

Because the vibration impact of the high-pressure oil pump can be transmitted to the camshaft gear 200 through the high-pressure oil pump driving gear 600 and the intermediate gear 400, the vibration impact of the camshaft 300 directly acts on the camshaft gear 200, along with the increase of the vibration impact of the high-pressure oil pump, the camshaft 300 and the like in an engine gear train, if the initial gear train is unreasonable in arrangement, the transmission of the water pump driving gear 500 in the gear train is unstable, the fluctuation of the rotating speed and the fluctuation of the torque of the gear train are large, the damage of a water pump bearing and the increase of water seal water leakage faults.

Disclosure of Invention

The invention aims to provide a gear train and an engine, which ensure that the transmission of a water pump driving gear is stable, reduce the fluctuation of the rotating speed of a water pump and have good reliability.

In order to achieve the purpose, the invention adopts the following technical scheme:

a gear train comprising intermeshing crankshaft and camshaft gears, further comprising:

the supporting shaft is arranged on the cam shaft gear in a protruding mode;

the outer-layer gear is sleeved on the supporting shaft and can rotate relative to the supporting shaft;

a water pump driving gear meshed with the outer layer gear;

the crankshaft gear is configured to drive the camshaft gear to rotate, and the water pump driving gear is driven to rotate through the outer layer gear.

Preferably, an axial clearance exists between the outer gear and the cam gear.

Preferably, a radial gap exists between the outer gear and the support shaft.

Preferably, pressure oil for lubricating between the outer gear and the support shaft is filled in the radial gap.

Preferably, the gear train further comprises a camshaft and an intermediate gear, and the camshaft gear and the intermediate gear are coaxially sleeved on the camshaft.

Preferably, the gear train further includes a high-pressure oil pump driving gear that is meshed with the intermediate gear.

Preferably, the intermediate gear and the cam gear are connected by a bolt.

Preferably, a central hole is formed in the outer gear, and the support shaft penetrates through the central hole.

Preferably, the gear train further includes a cover plate located at one side of the support shaft and disposed in the central hole.

To achieve the above object, the present invention further provides an engine including the above gear train.

The invention has the beneficial effects that:

according to the gear train provided by the invention, the support shaft penetrates through the outer-layer gear, so that the outer-layer gear is supported and rotated by the support shaft, the crankshaft gear is configured to drive the camshaft gear to rotate, and the water pump driving gear is driven to rotate by the outer-layer gear, so that the torque transmission of the crankshaft gear, the outer-layer gear and the water pump driving gear is realized. Compare with prior art camshaft gear and intermediate gear rigid connection, outer gear can be rotatory round the back shaft, outer gear breaks away from completely at the circumferencial direction with camshaft gear, outer gear and camshaft gear both are in the free not hard up state, can not transmit impact load, avoid camshaft gear to transmit the fluctuation of impact speed for outer gear, the problem that water pump drive gear rotational speed is undulant big has been solved, guarantee water pump drive gear transmission stationarity, thereby reduce water pump bearing and water seal fault rate of leaking, service life has been prolonged.

The invention also provides an engine which comprises the gear train, so that the transmission stability of the water pump driving gear is ensured, the rotation speed fluctuation and the torque fluctuation of the gear train are reduced, and the rotation speed fluctuation fault of the water pump is reduced, thereby improving the reliability and the safety.

Drawings

FIG. 1 is a cross-sectional view of a prior art engine gear train;

FIG. 2 is an exploded schematic view of the gear train of the present invention;

FIG. 3 is a cross-sectional view of the gear train of the present invention.

In the figure:

100. a crankshaft gear; 200. a camshaft gear; 300. a camshaft; 400. an intermediate gear; 500. the water pump drives the gear; 600. a high-pressure oil pump driving gear;

1. a crankshaft gear; 2. a camshaft gear; 3. a support shaft; 4. an outer gear; 5. the water pump drives the gear; 6. a camshaft; 7. an intermediate gear; 8. a high-pressure oil pump driving gear; 9. a cover plate;

41. a central bore.

Detailed Description

In order to make the technical problems solved, technical solutions adopted and technical effects achieved by the present invention clearer, the technical solutions of the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, unless expressly stated or limited otherwise, the terms "connected," "connected," and "fixed" are to be construed broadly, e.g., as meaning permanently connected, removably connected, or integral to one another; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

The technical scheme of the invention is further explained by the specific implementation mode in combination with the attached drawings.

The embodiment provides a gear train, which is mainly applicable to a gear train of an engine, as shown in fig. 2-3, the gear train comprises a crankshaft gear 1, a camshaft gear 2, a support shaft 3, an outer gear 4 and a water pump driving gear 5, wherein the crankshaft gear 1 and the camshaft gear 2 are meshed with each other, the support shaft 3 is arranged on the camshaft gear 2 in a protruding mode, a central hole 41 is formed in the outer gear 4, the support shaft 3 penetrates through the central hole 41, the outer gear 4 is sleeved on the support shaft 3 and can rotate relative to the support shaft, the outer gear 4 is meshed with the water pump driving gear 5, and the crankshaft gear 1 is configured to drive the camshaft gear 2 to rotate and drive the water pump driving gear 5 to.

In the gear train provided by the embodiment, the supporting shaft 3 penetrates through the outer gear 4, so that the outer gear 4 is supported and rotated by the supporting shaft 3, the crankshaft gear 1 is configured to drive the camshaft gear 2 to rotate, and the outer gear 4 drives the water pump driving gear 5 to rotate, thereby realizing torque transmission of the crankshaft gear 1, the outer gear 4 and the water pump driving gear 5. Compare with prior art camshaft gear 2 and 7 rigid connection of intermediate gear, outer gear 4 can be rotatory round support shaft 3, outer gear 4 breaks away from completely at the circumferencial direction with camshaft gear 2, both are in free not hard up state with camshaft gear 4, can not transmit impact load, avoid camshaft gear 2 to transmit the fluctuation of impact speed for outer gear 4, the problem that 5 undulant big of water pump drive gear rotational speed has been solved, guarantee 5 transmission stationarities of water pump drive gear, thereby reduce water pump bearing and water seal fault rate of leaking, and the service life is prolonged.

Because both the outer gear 4 and the camshaft gear 2 are in a free loose state, an axial gap exists between the outer gear 4 and the camshaft gear 2, so that the outer gear 4 can freely rotate around the supporting shaft 3. Further, in the case where there is a micro-motion between the outer gear 4 and the support shaft 3, there is a radial gap between the outer gear 4 and the support shaft 3, and pressure oil is filled in the radial gap, and the pressure oil is used for lubrication between the outer gear 4 and the support shaft 3. The radial clearance is lubricated by introducing pressure oil, so that the problem of heating and sintering is avoided, the fault occurrence rate is reduced, and the reliability is good.

It can be understood that the radial clearance between the outer gear 4 and the support shaft 3 and the axial clearance between the outer gear 4 and the camshaft gear 2 are determined through simulation and test means, and the purpose of greatly reducing the fluctuation of the rotating speed of the water pump driving gear 5 is achieved. Through accurate simulation calculation, the fluctuation of the rotating speed of the water pump can be reduced by about 19%, and the fluctuation of the torque can be reduced by about 25.8%.

Further, the gear train further comprises a camshaft 6, an intermediate gear 7 and a high-pressure oil pump driving gear 8, the camshaft 6 is coaxially sleeved with the camshaft gear 2 and the intermediate gear 7, and the intermediate gear 7 is connected with the camshaft gear 2 through bolts, so that the intermediate gear 7 is rigidly connected with the camshaft gear 2. When the crankshaft gear 1 drives the camshaft gear 2 to rotate, the camshaft gear 2 drives the camshaft 6 to drive the intake valve and the exhaust valve to open and close, meanwhile, the intermediate gear 7 rotates along with the rotation of the camshaft gear 2, and the intermediate gear 7 is meshed with the high-pressure oil pump driving gear 8, so that the intermediate gear 7 drives the high-pressure oil pump driving gear 8 to rotate.

Because outer gear 4 is not with camshaft gear 2 rigid connection, outer gear 4 only can be rotatory around back shaft 3, and when camshaft gear 2 drove back shaft 3 and rotates, outer gear 4 only is the follow-up action, does not have direct contact between outer gear 4 and the camshaft gear 2, avoids high-pressure oil pump and camshaft 6 to strike the circumferencial direction rotational speed fluctuation that arouses and transmits for camshaft gear 2, reduces the water pump rotational speed and fluctuates. On the premise that the gear train cannot be greatly changed, the influence of vibration impact of the high-pressure oil pump and the camshaft 6 on the instability of the gear train is reduced, and the reliability is improved.

Further, in order to avoid the influence on the appearance of the support shaft 3 due to the exposure, the gear train further comprises a cover plate 9, the cover plate 9 is located on one side of the support shaft 3 and is arranged in the central hole 41 of the outer gear 4, and the cover plate 9 plays a role in shielding the support shaft 3 and has the functions of dust prevention, water prevention and sealing. Alternatively, the cover plate 9 and the support shaft 3 may be connected by screws.

The embodiment also provides an engine, and the engine comprises the gear train, so that the transmission stability of the water pump driving gear 5 is ensured, the fluctuation of the rotating speed and the torque of the gear train are reduced, and the fluctuation fault of the rotating speed of the water pump is reduced, thereby improving the reliability and the safety.

In the description herein, it is to be understood that the terms "upper", "lower", "right", and the like are based on the orientations and positional relationships shown in the drawings and are used for convenience in description and simplicity in operation, but do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed in a particular orientation, and be constructed in a particular operation, and thus should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used merely for descriptive purposes and are not intended to have any special meaning.

In the description herein, references to the description of "an embodiment," "an example" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example.

In addition, the foregoing is only the preferred embodiment of the present invention and the technical principles applied. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail by the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present invention, and the scope of the present invention is determined by the scope of the appended claims.