External balance shaft mounting structure of motorcycle engine

Abstract

The utility model discloses an external balance shaft installation structure of a motorcycle engine, the engine is provided with a crankcase, a case cover installed on the outer side of the crankcase and a crank connecting rod mechanism installed in the crankcase, a containing cavity is formed between the case cover and the crankcase, and a balance shaft is installed in the containing cavity in a rotating mode. The balance shaft is parallel to the axis of the crank-link mechanism, and the rotating end, located in the containing cavity, of the crank-link mechanism is connected with the balance shaft through a gear pair. According to the external balance shaft mounting structure, the balance shaft originally arranged in the crankcase of the engine is externally arranged, and on the basis of reducing noise and vibration, on one hand, the external balance shaft is convenient to mount, maintain and replace; and secondly, under the condition that the space in the crankcase is limited, the external balance shaft can leave more installation space so as to avoid the installation of other parts in the crankcase.

Description

Technical Field

[0001] The utility model relates to the technical field of motorcycle engines, in particular to an external balance shaft installation structure for a motorcycle engine. Background Art

[0002] With the market demand for higher engine speeds for large-displacement motorcycles, the engine has problems with insufficient stability, obvious vibration and noise due to the extremely high speed. The main reason for the problem is that the crank-connecting rod mechanism, as the core component of the engine, generates a strong reciprocating inertia force during high-speed operation, which intensifies the engine vibration, so the design of a balance shaft is very necessary.

[0003] Generally, the balance shaft and the crank-connecting rod mechanism are installed in the crankcase. However, as people have higher and higher requirements for motorcycle engine performance, the structure of the engine has become more and more complicated. In the case of limited space inside the crankcase, the balance shaft, as an additional component, needs to avoid the installation of other necessary components, and the installation of the balance shaft needs to find a new way. There is an urgent need for a balance shaft installation structure that can be designed to be installed on the outside of the crankcase, which can also achieve the purpose of balancing the reciprocating inertia force and improve the stability of the engine. Utility Model Content

[0004] The utility model aims to provide an external balancing shaft installation structure for a motorcycle engine, so as to solve the problem that the balancing shaft and the crank-connecting rod mechanism of the existing engine are both arranged in the crankcase, resulting in limited space inside the crankcase.

[0005] In order to solve the above technical problems, the utility model adopts the following technical solutions:

[0006] A motorcycle engine external balance shaft installation structure, the engine comprises a crankcase, a case cover installed on the outside of the crankcase and a crank-connecting rod mechanism installed in the crankcase, an accommodating cavity is formed between the case cover and the crankcase, a balance shaft is rotatably installed in the accommodating cavity, the balance shaft is arranged parallel to the axis of the crank-connecting rod mechanism, and the rotating end of the crank-connecting rod mechanism located in the accommodating cavity is connected to the balance shaft through a gear pair.

[0007] A further technical solution is: the gear pair includes a primary gear, an oil pump gear, a driving gear and a driven gear, the primary gear, the oil pump gear and the driving gear are all installed on the rotating end of the crank-connecting rod mechanism located in the accommodating cavity, and the driving gear is meshed with the driven gear installed on the balance shaft.

[0008] A further technical solution is: a balance shaft mounting seat installed on the side of the crankcase is provided in the accommodating cavity.

[0009] A further technical solution is that a counterweight is arranged on the balancing shaft.

[0010] A further technical solution is that the accommodating chamber is arranged away from the power output end of the crank-connecting rod mechanism.

[0011] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0012] The utility model proposes an external balancing shaft installation structure for a motorcycle engine. The external balancing shaft installation structure places the balancing shaft originally arranged in the engine crankcase outside. On the basis of reducing noise and vibration, on the one hand, the external balancing shaft is convenient for installation, maintenance and replacement; on the other hand, when the space in the crankcase is limited, the external balancing shaft can leave more installation space to avoid the installation of other components in the crankcase. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 The utility model is a structural schematic diagram of an external balance shaft installation structure of a motorcycle engine.

[0014] Figure 2 For this utility model Figure 1 Schematic diagram of the structure of the crank-connecting rod mechanism and gear pair.

[0015] Figure 3 For this utility model Figure 1 Schematic diagram of the crankcase structure.

[0016] Figure 4 For this utility model Figure 1 Schematic diagram of the structure of the middle box cover.

[0017] Figure numerals: 1. crankcase; 2. case cover; 3. crank-connecting rod mechanism; 4. balance shaft; 5. gear pair; 6. primary gear; 7. oil pump gear; 8. driving gear; 9. driven gear; 10. balance shaft mounting seat; 11. counterweight. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. The components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0019] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention.

[0020] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features thereof may be combined with each other.

[0021] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0022] In the description of the present utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the utility model product is usually placed when in use, or the positions or positional relationships commonly understood by those skilled in the art, which are only for the convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0023] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0024] Embodiment 1:

[0025] In this embodiment, Figure 1 , Figure 2 , Figure 3 and Figure 4As shown, a motorcycle engine external balance shaft installation structure, the engine comprises a crankcase 1, a case cover 2 installed on the outside of the crankcase 1 and a crank-connecting rod mechanism 3 installed in the crankcase 1, an accommodating cavity is formed between the case cover 2 and the crankcase 1, a balance shaft 4 is rotatably installed in the accommodating cavity, the balance shaft 4 is arranged parallel to the axis of the crank-connecting rod mechanism 3, and the rotating end of the crank-connecting rod mechanism 3 located in the accommodating cavity is connected to the balance shaft 4 through a gear pair 5.

[0026] One end of the balance shaft 4 is first connected to the outside of the crankcase 1 by rotation, and then the rotating end of the crank-connecting rod mechanism 3 is connected to the balance shaft 4 by using the gear pair 5, and then the case cover 2 is covered on the outside of the crankcase 1 to complete the sealing of the balance shaft 4 and the gear pair 5, and the balance shaft 4 and the case cover 2 are also rotated and matched. The external balance shaft installation structure places the balance shaft originally placed in the engine crankcase externally, and on the basis of reducing noise and vibration, on the one hand, the external balance shaft is convenient for installation, maintenance and replacement; on the other hand, when the space in the crankcase is limited, the external balance shaft can leave more installation space to avoid the installation of other components in the crankcase.

[0027] Preferably, the gear pair 5 includes a primary gear 6, an oil pump gear 7, a driving gear 8 and a driven gear 9. The primary gear 6, the oil pump gear 7 and the driving gear 8 are all installed on the rotating end of the crank-connecting rod mechanism 3 located in the accommodating cavity, and the driving gear 8 is meshed with the driven gear 9 installed on the balance shaft 4.

[0028] The primary gear 6, the oil pump gear 7 and the driving gear 8 are installed together on the rotating end of the crank-connecting rod mechanism 3 located in the accommodating cavity through nuts. The primary gear 6 is used to drive the clutch to transmit power, the oil pump gear 7 is used to drive the oil pump to lubricate the engine, and the driving gear 8 drives the balancing driven gear 9 to drive the balancing shaft 4 to rotate, so as to achieve the purpose of balancing the inertial force.

[0029] Preferably, a balance shaft mounting seat 10 mounted on the side of the crankcase 1 is provided in the accommodating cavity.

[0030] The balancing shaft mounting seat 10 is used for installing the balancing shaft 4.

[0031] Preferably, a counterweight 11 is provided on the balancing shaft 4 .

[0032] The balancing weight 11 enhances the vibration-damping effect when the balancing shaft 4 rotates.

[0033] Preferably, the accommodating chamber is arranged away from the power output end of the crank-connecting rod mechanism 3 .

[0034] To avoid the operation of the power output end of the crank-connecting rod mechanism 3.

[0035] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A motorcycle engine external balance shaft mounting structure, the engine comprising a crankcase (1), a case cover (2) mounted outside the crankcase (1), and a crank-connecting rod mechanism (3) mounted inside the crankcase (1), characterized in that: An accommodating cavity is formed between the case cover (2) and the crankcase (1), a balancing shaft (4) is rotatably mounted in the accommodating cavity, the balancing shaft (4) is arranged parallel to the axis of the crank-connecting rod mechanism (3), and the rotating end of the crank-connecting rod mechanism (3) located in the accommodating cavity is connected to the balancing shaft (4) via a gear pair (5).

2. The motorcycle engine external balance shaft installation structure according to claim 1, characterized in that: The gear pair (5) comprises a primary gear (6), an oil pump gear (7), a driving gear (8) and a driven gear (9); the primary gear (6), the oil pump gear (7) and the driving gear (8) are all mounted on the rotating end of the crank-connecting rod mechanism (3) located in the accommodating cavity; the driving gear (8) meshes with the driven gear (9) mounted on the balance shaft (4).

3. The motorcycle engine external balance shaft installation structure according to claim 1, characterized in that: A balance shaft mounting seat (10) mounted on the side of the crankcase (1) is provided in the accommodating cavity.

4. The motorcycle engine external balance shaft mounting structure according to claim 1, characterized in that: A counterweight block (11) is arranged on the balancing shaft (4).

5. The motorcycle engine external balance shaft mounting structure according to claim 1, characterized in that: The accommodating chamber is arranged away from the power output end of the crank-connecting rod mechanism (3).

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