CN216130975U

CN216130975U - Oil pump gear and motorcycle engine adopting same

Info

Publication number: CN216130975U
Application number: CN202120749240.7U
Authority: CN
Inventors: 杨陈; 鞠树利; 舒桂明
Original assignee: Zhejiang CFMOTO Power Co Ltd
Current assignee: Zhejiang CFMOTO Power Co Ltd
Priority date: 2020-11-20
Filing date: 2021-04-13
Publication date: 2022-03-25
Anticipated expiration: 2031-04-13
Also published as: CN214787686U; CN215486293U; CN113090382B; CN215487442U; CN113090382A; CN214787659U; CN214787751U; CN214787687U; CN113090424A; CN214787698U; CN214787738U; WO2022105099A1; CN214787688U; CN113090424B; CN216130999U; CN113090384A; CN113090386A; CN113090385A

Abstract

The utility model discloses an oil pump gear which comprises a disc-shaped wheel disc, wherein a plurality of gear teeth are arranged on the edge of the wheel disc along the circumferential direction; the sleeve hole is arranged on the driving gear, and the sleeve hole and the driving gear are arranged concentrically; the pin hole is arranged on the driving gear, corresponds to a pin rod on the oil pump, and is communicated with the trepanning. The driving gear designed by the utility model has reduced requirements on the distance between the pin rods matched with the pin holes and the diameter of the pin rods, and the related performance of the oil pump cannot be influenced under the condition that the distance between the two pin rods has an inward error.

Description

Oil pump gear and motorcycle engine adopting same

Technical Field

The utility model relates to the technical field of motorcycle engines, in particular to an oil pump gear and a motorcycle engine adopting the oil pump gear.

Background

Classification as to engine;

1. engines are classified into gasoline engines and diesel engines according to the fuel used by the engine. Internal combustion engines using gasoline as a fuel are called gasoline engines; internal combustion engines that use diesel engines as fuel are referred to as diesel engines. Gasoline engines and diesel engines have various characteristics; the gasoline engine has high rotating speed, low quality, low noise, easy starting and low manufacturing cost; the diesel engine has large compression ratio, high heat efficiency, and better economic performance and discharge performance than the gasoline engine.

2. Four-stroke engines and two-stroke engines can be classified according to the number of strokes required by the engine to complete one work cycle. The internal combustion engine which rotates the crankshaft for two circles (720 degrees), and the piston reciprocates up and down in the cylinder for four strokes to complete one working cycle is called a four-stroke engine; an engine in which a piston reciprocates up and down in a cylinder for two strokes during one rotation (360 °) of a crankshaft is called a two-stroke engine.

3. According to different cooling modes of the engine, the engine can be divided into a water-cooled engine and an air-cooled engine. The water-cooled engine is cooled by using coolant circulating in a cylinder block and cylinder head cooling jacket as a cooling medium; the air-cooled engine is cooled by using air flowing between the cylinder block and the radiating fins on the outer surface of the cylinder cover as a cooling medium; the water-cooled engine has uniform cooling, reliable work and good cooling effect.

4. The engine is divided into a single-cylinder engine and a multi-cylinder engine according to different numbers of cylinders on the engine. An engine with only one cylinder is called a single cylinder engine; engines having two or more cylinders are referred to as multi-cylinder engines.

5. The cylinder arrangement of the engine can be divided into a single-row type and a double-row type. The cylinders of a single-row engine are lined up, generally vertically, but sometimes inclined or even horizontal in order to reduce the height; a two-row engine is referred to as a V-engine when the angle between two rows is 180 ° (typically 90 °) and an opposed engine when the angle between two rows is 180 °.

The driving gear of engine oil usually is pin rod and pinhole cooperation, that is to say, set up two pinholes of associating the cooperation with the pin rod on the driving gear, and this kind of cooperation mode has the following problem in the assembly process, and the precision that is to the distance between pin rod diameter and two pin rods is very high, when there is the difference in the diameter of pin rod and pinhole, or when there is the difference in the distance between the pin rod and the distance between the pinhole, often difficult assembly driving gear.

SUMMERY OF THE UTILITY MODEL

The utility model provides an oil pump gear for overcoming the defects of the prior art.

In order to achieve the purpose, the utility model adopts the following technical scheme: the oil pump gear comprises a disc-shaped wheel disc, wherein a plurality of gear teeth are arranged on the edge of the wheel disc along the circumferential direction;

the sleeve hole is arranged on the driving gear, and the sleeve hole and the driving gear are arranged concentrically;

the pin hole is arranged on the driving gear, corresponds to a pin rod on the oil pump, and is communicated with the trepanning.

Optionally, the cross section of the pin hole is in a U shape.

Optionally, at least two pin holes are arranged, and the two pin holes are symmetrically arranged relative to the trepanning.

Optionally, the pin hole penetrates through the driving gear along a thickness direction of the driving gear.

Optionally, the driving gear is further provided with an annular groove.

Optionally, the annular groove and the trepan boring are concentrically arranged.

Optionally, the distance from the annular groove to the center of the driving gear is greater than the maximum distance from the inner wall of the pin hole to the center of the driving gear.

The utility model also discloses a motorcycle engine, which comprises the oil pump gear and the motorcycle engine

A cylinder block;

a cylinder head connected to the cylinder block;

the cylinder cover is connected with the cylinder cover;

a crankshaft;

a connecting rod;

the piston is connected with the crankshaft through a connecting rod;

a balancing device associated with the crankshaft.

In summary, the requirements of the driving gear designed by the utility model on the distance between the pin rods matched with the pin holes and the diameter of the pin rods are reduced, and the related performance of the oil pump is not influenced under the condition that the distance between the two pin rods has an inward error.

Drawings

Fig. 1 is a left side view of a motorcycle driven by an engine of the present invention.

Fig. 2 is a perspective view of the engine of the present invention.

Fig. 3 is a perspective view from another perspective of the engine of fig. 2.

FIG. 4 is a perspective view of the crankshaft and counterbalance assembly of FIG. 2 in relation thereto.

Fig. 5 is a perspective view of another form of the balancing apparatus of fig. 2.

Fig. 6 is a perspective view of the balancing apparatus of fig. 2 with only one balancing shaft extending through the engine.

Fig. 7 is an exploded view of the water pump assembly and first balance shaft assembly of fig. 2.

FIG. 8 is a perspective view of the water pump and first balance shaft assembly of FIG. 2 in relation thereto.

FIG. 9 is a cross-sectional view of the water pump and first balance shaft assembly of FIG. 2 in relation thereto.

Fig. 10 is a perspective view of the seal ring of fig. 7.

Fig. 11 is a cross-sectional view of the seal ring of fig. 7.

Fig. 12 is a front view of the piston and connecting rod of fig. 1.

Fig. 13 is an exploded view of fig. 12 with a piston pin installed.

Fig. 14 is a perspective view of the rotor and crankshaft of fig. 1.

Fig. 15 is a cross-sectional view taken at C-C in fig. 14.

Fig. 16 is an enlarged view of fig. 15 at B.

Fig. 17 is an exploded view of fig. 15.

FIG. 18 is a perspective view of the oil pump gear of FIG. 1.

Detailed Description

In order to make the technical solutions of the present invention better understood, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and the structures related to the present invention or the technical terms used in the structures are optionally described below, and unless otherwise specified, they are understood and explained according to the general genus in the art. The terms "first", "second", and the like, appearing in the present invention are for convenience of description only, to distinguish different constituent elements having the same name, and do not denote a sequential or primary-secondary relationship. In the following description, the front-rear direction and the left-right direction correspond to directions based on the rider's perspective, and the front, rear, left, right, up, down directions are described as the directions shown in fig. 1.

Dynamic seal

Dynamic means that relative motion occurs between two parts, i.e. one part is stationary and the other part rotates or translates relatively; the sealing means that two parts are contacted with each other, and media such as air, liquid and the like cannot pass through the contact points of the two parts; dynamic sealing thus means that two parts, which can be rotated or moved relative to each other, remain in contact with each other without liquid and/or gas passing through them.

Cooling liquid

The cooling liquid is the essential working medium for guaranteeing normal work of the water-cooled engine, is used for absorbing temperature under the pumping of a water pump in a circulating flow mode, and most of the conventional cooling liquid is water at present.

Transverse direction

The transverse direction in the present invention is specifically along the length of the crankshaft.

Axial pressure

The axial pressure refers to a pressure formed along the length direction of the shaft, and the direction of the pressure is parallel to the length direction of the shaft.

Is smooth and smooth

The surface of the wall has no obvious bulge and thread; for example, the shank of the bolt may be unthreaded, or the inner wall of the blind bore may be unthreaded, and the wall surface may be smooth, with no threads or protrusions.

Fig. 1 is a left side view of a motorcycle 10 showing the driving of an engine 16 according to an embodiment of the present invention.

Referring to fig. 1, a motorcycle 10 includes a frame 11 formed by welding metal pipes and plates, a front wheel 12, a rear wheel 13, a fuel system 14, a body cover 15, an engine 16, a controller 17, an instrument panel 18, a suspension system 19, and the like. The motorcycle 10 is a large displacement two-wheeled fuel-powered motorcycle, although in other embodiments the motorcycle may be a four-wheeled dirtbike. The suspension system 19 includes a front suspension 191 and a rear suspension 192, the front suspension 191 engaging the front portion of the frame 11, the front suspension 191 being associated with the front wheel 12. A rear suspension is engaged at the rear of the frame 11 and is associated with a rear wheel 13. A fuel system 14 is provided on the frame 11, the fuel system 14 being adapted to provide fuel to the engine 16.

The engine 16 of the motorcycle 10 drives the sprocket 1311 on the hub 131 of the rear wheel 13 to rotate through a chain (not shown), and then drives the rear wheel 13 to rotate, so that the rear wheel 13 pushes the motorcycle 10 to move forward. The engine 16 is supported at a middle and lower position of the frame 11, and the engine 16 is fixed to the frame 11 by bolts.

Fig. 2 is a perspective view showing the engine 16 of the present invention from the front right, and the right engine case is not shown in this figure. Fig. 3 is a perspective view of the engine 16 of the present invention viewed from the front left, with the left engine case not shown.

Referring to fig. 2 and 3 and 7, a combustion chamber (not shown) is provided in the engine 16, and fuel from the fuel system 14 is routed into the combustion chamber and ignited by a spark plug (not shown) of the engine 16, where the fuel generates kinetic energy that propels the piston 40 downward to power the motorcycle 10. The engine 16 includes a cylinder block 161, a cylinder head 162, a cylinder head cover 163, a crankcase 164, a water pump device 30, a crankshaft 60, a balancing device 20, a piston 40, and an intake system 73.

Fig. 4 shows a perspective view of the crankshaft 60 and the balancing device 20 in the engine 10 of fig. 2 in relation thereto.

In some embodiments, referring to fig. 4, the balancing device 20, which is actually one or two balancing shafts rotating synchronously with the crankshaft 60, utilizes the opposite vibration force generated by the balancing device 20 during rotation to achieve good balancing effect for the engine and reduce the vibration of the engine 16. The balancing device 20 has the following components: a first balance shaft assembly 21 offset to the right of engine 16 and a second balance shaft assembly 22 offset to the left of engine 16. The first balance shaft assembly 21 and the second balance shaft assembly 22 do not require symmetrical arrangement on the engine 16, and mainly achieve balance on the engine 16 according to the positions of the mass centers of the first balance shaft assembly 21 and the second balance shaft assembly 22 on the engine 16, so that vibration of the engine 16 is reduced. The first balance shaft assembly 21 and the second balance shaft assembly 22 are separately arranged at different positions of the engine 16, the installation positions of the first balance shaft assembly 21 and the second balance shaft assembly 22 are diversified, and the occupied space on the engine 16 is small, so that the structure of the engine 16 of the motorcycle 10 is compact.

As described above, the first balance shaft assembly 21 is linked to the right end of the crankshaft 60 by a gear or a sprocket, and the first balance shaft assembly 21 includes the first shaft body 211, the first gear 212, and the first weight 213. The first shaft body 211 is provided in the crankcase 164 along the width direction of the motorcycle 10. The first shaft body 211 and the first gear 212 are integrated together and are of an integrated structure; of course, the two gears may be of a split structure, and then the two gears are connected by press fitting or bolt connection, so that the first shaft 211 and the first gear 212 rotate synchronously.

In addition, a circle of the first gear 212 near the periphery of the first shaft 211 protrudes from left to right to form a circle of convex ring 2122, and approximately one third of the outer edge of the convex ring 2122 extends towards the gear teeth of the first gear 212 to form a fan-shaped first weight 213, so that the first weight 213 is a part of the first gear 212; therefore, the whole first balance shaft assembly 21 is compact, the occupied space in the engine 16 is small, and the engine 16 is compact. The distance from the edge of the first weight 213 near the gear teeth to the center of the first gear 212 is smaller than the distance from the tooth root of the first gear 212 to the center of the first gear 212. Therefore, the thickness of the gear teeth on the first gear 212 is consistent, and after the first gear 212 is meshed with the gear on the crankshaft 60, the force of each gear tooth is consistent to ensure that the first gear 212 works stably.

Referring also to fig. 4, the first gear 212 is provided with five first weight-reducing holes 2121 in a region other than the portion occupied by the first weight 213, the five first weight-reducing holes 2121 are arranged along the circumferential direction of the first gear 212, and the distances between two adjacent first weight-reducing holes 2121 are the same. Only a portion of the first gear 212 is provided with the first lightening hole 2121 so that the first gear 212 forms an eccentric gear to generate vibration when rotating, and the vibration generated from the first gear 212 and the vibration generated from the first weight 213 are added to each other to improve the vibration damping effect of the engine 16.

As shown in fig. 4, the second balance shaft assembly 22 is engaged with the gear of the left journal of the crankshaft 60 through a gear, so that the second balance shaft assembly 22 and the crankshaft 60 synchronously move. The second balance shaft assembly 22 includes a second shaft body 221, a second gear 222, and a second weight 223. The second shaft body 221 is provided in the crankcase 30 along the width direction of the motorcycle 10. The second shaft 221 and the second gear 222 are integrated together and are of an integrated structure; of course, the two components may be in a split structure, and then the two components are connected by press fitting or bolt connection, so that the second shaft 221 and the second gear 222 rotate synchronously.

In addition, the second gear 222 is circumferentially protruded from left to right in a circle near the second shaft 221 to form a circle of convex ring 2222, and a fan-shaped second weight 223 is formed by extending approximately one third of the outer edge of the convex ring 2222 toward the gear teeth of the second gear 222, so that the second weight 223 is a part of the second gear 222; therefore, the entire second balance shaft assembly 22 is compact, the space occupied inside the engine 16 is small, and the engine 16 is compact. The distance from the edge of the second weight 223 near the gear teeth to the center of the second gear 222 is less than the distance from the root of the second gear 222 to the center of the second gear 222. Therefore, the thickness of the gear teeth on the second gear 222 is consistent, and after the second gear 222 is meshed with the gear on the crankshaft 60, the force of each gear tooth is consistent to ensure that the second gear 222 works stably.

As shown in fig. 3 and 4, the second gear 222 is provided with five second weight-reducing holes 2221 in a region other than the portion occupied by the second weight 223, the five second weight-reducing holes 2221 are arranged along the circumferential direction of the second gear 222, and the distances between two adjacent second weight-reducing holes 2221 are the same. Only a portion of the second gear 222 is provided with the second lightening hole 2221 so that the second gear 222 forms an eccentric gear to generate vibration when rotating, and the vibration generated from the second gear 222 and the vibration generated from the second weight 223 are added to each other, thereby improving the vibration damping effect of the engine 16.

Fig. 5 is a perspective view of another aspect of the balancing apparatus 20 of the engine 10 of fig. 2.

The above embodiment is an aspect of the present invention, and appropriate modifications may be made without departing from the scope of the present invention, and referring to fig. 5, in some embodiments, the first weight 213b is integrated with the first shaft body 211b, the first weight 213b is a part of the first shaft body 211b, and then the first shaft body 211b is connected to a gear or a sprocket to be interlocked with the crankshaft.

The above embodiment is an aspect of the present invention, and appropriate modifications may be made without departing from the scope of the present invention, and for example, referring to fig. 5, in some embodiments, the second weight 223b is integrated with the second shaft body 221b, the second weight 223b is a part of the second shaft body 221b, and then the second shaft body 221b is further connected with a gear or a sprocket to be interlocked with the crankshaft.

Fig. 6 shows a perspective view of the balancing device 20 of the engine 10 of fig. 2 with only one balancing shaft extending through the engine 16.

Of course, in addition to the several embodiments described above, referring to fig. 6, in some other embodiments, the balancing device 20 of the engine 16 is provided with only one balancing shaft 23 extending through the engine 16. The balance shaft 23 includes a shaft 231 and two balance weights 232, one of the two balance weights 231 is integrated near the right end of the shaft 231, and the other is integrated near the left end of the shaft 231. The counterbalances 232 are sectors integrated on the shaft 231, each counterbalance 232 being located on one side of the engine 16, and the two counterbalances 232 being symmetrically located.

Fig. 7 shows an exploded view of the water pump arrangement 30 and the first balance shaft assembly 21 of the engine 10 of fig. 2. Fig. 8 illustrates a perspective view of the water pump 32 and the first balance shaft assembly 21 associated with the engine 10 of fig. 2. Fig. 9 shows a cross-sectional view of the water pump 32 and the first balance shaft assembly 21 of the engine 10 of fig. 2.

Referring to fig. 7 and 8, one of the first balance shaft assembly 21 or the second balance shaft assembly 22 is used to transfer kinetic energy of the crankshaft 60 to the water pump apparatus 30. That is, one of the first balance shaft assembly 21 and the second balance shaft assembly 22 not only reduces the vibration of the engine 60, but also drives the water pump device 30 to operate. The axial pressure of the coolant on the first balance shaft assembly 21 or the second balance shaft assembly 22 and the axial pressure of the lubricating oil on the first balance shaft assembly 21 or the second balance shaft assembly 22 are opposite to each other, and the two forces are counteracted to keep the first balance shaft assembly 21 or the second balance shaft assembly 22 from moving in the engine 60, and further keep the first balance shaft assembly 21 or the second balance shaft assembly 22 stable in the position of the engine 60, wherein the first shaft body 211 of the first balance shaft assembly 21 serves as a power shaft of the water pump device 30.

Wherein the water pump device 30 comprises a water pump housing 31 and a water pump 32, the water pump housing 31 is fixed on the right side of the engine 16 through bolts, and a ring of rubber sealing piece 33 is arranged between the water pump housing 31 and the main body of the engine 16. The water pump shell 31 is provided with a liquid inlet channel 311 extending from front to back to the middle of the engine 16, the inner wall of the liquid outlet end of the liquid inlet channel 311 is an arc-shaped surface to form a turn, and cooling liquid enters from the liquid inlet end of the liquid inlet channel 311 and then enters the water pump 32 at the liquid outlet end in a turn. A water pump cavity 312 communicated with the liquid inlet channel 311 is arranged at the position, close to the liquid outlet end of the liquid inlet channel 311, of the water pump shell 31, and the water pump 32 is arranged in the water pump cavity 312. A 6-shaped flow passage 313 is formed around the water pump chamber 312, the coolant enters through the liquid inlet passage and then enters the water pump 32 located in the water pump chamber 312, the water pump 32 pumps the coolant into the flow passage 313, and then the coolant flows into a cooling pipeline (not shown) of the engine 16 through the flow passage 313 to cool the engine.

In addition, the water pump 32 includes an impeller 321 and an end cover 322, the impeller 321 has a curved cover 3211 and a plurality of blades 3212, the curved shape of the right side wall of the curved cover 3211 is the same as the curved shape of the inner wall of the water pump chamber 312, and the curved cover 3211 is attached to the side wall of the water pump chamber 312. The curved surface cover 3211 is provided with a liquid inlet opening 3213, the liquid inlet opening 3213 corresponds to the liquid outlet end of the liquid inlet channel 311, and the cooling liquid turns at the liquid outlet end of the liquid inlet channel 311 and then enters the water pump 32 through the liquid inlet opening 3213. The vanes 3212 are part of a curved cover 3211, the number of vanes 3212 is six, and six vanes 3212 are arranged circumferentially along the curved cover 3211. The end cover 322 is connected with the impeller 321 through a bolt, six positioning grooves 3221 are arranged on the end cover 322, and one side of the blade 3212 far away from the curved surface cover 3211 is embedded into the positioning grooves 3221.

In addition, the water pump 32 is connected to the first shaft body 211 through the bolt 34, in fact, the platform 210 is arranged on the first shaft body 211, after the end cover 322 is sleeved on the first shaft body 211, the left side wall of the end cover 322 is connected with the platform 210, and the end cover 322 can not move towards the left on the first shaft body 211 any more. Then, the first shaft body 211 is connected through the bolt 34, the bolt 34 presses the impeller 321 onto the first shaft body 211, and the impeller 321 presses the end cover 322 to realize the installation of the water pump 32 and the balance shaft 20.

Referring to fig. 9, the first balance shaft assembly 21 has a lubricant flowing chamber 200, an oil inlet 201 communicating with the lubricant flowing chamber 200, and an oil outlet 202 communicating with the lubricant flowing chamber, the distance from the oil outlet 202 to the water pump is close to the distance from the oil inlet 201 to the water pump 32, the oil outlet 202 corresponds to the bearing 24 sleeved on the first balance shaft assembly 21, and the bearing 24 sleeved on the first balance shaft assembly 21 is lubricated, so that the wear of the bearing 24 is reduced, the heat generated by the engine is reduced, and the working efficiency of the engine is improved.

From the foregoing, it can be known that the bearings need lubricating oil lubrication, the water pump needs to pump coolant, and under the condition that the balance shaft drives the water pump to rotate, the shaft of the balance shaft needs to be separated from the lubricating oil and the coolant, so as to prevent the lubricating oil from being diluted and ensure the service life of the engine 16 during operation. Referring to fig. 9, a sleeve 205 is sleeved from the platform 210 to about one third of the first shaft body 211 from the right to the left, and an O-ring 207 for sealing the inner walls of the first shaft body 211 and the sleeve 205 is arranged between the shaft of the first shaft body 211 and the inner wall of the sleeve 205 to limit the contact and mixing of the cooling fluid and the lubricating oil. The corresponding sleeve 205 is sleeved with a sealing ring 206, the inner wall of the sealing ring 206 is in contact with the sleeve 205, the outer wall of the sealing ring 206 is connected with the engine 16, and when the first shaft body 211 is linked with the crankshaft 60, the first shaft body 211 rotates relative to the sealing ring 206, so that the first shaft body 211 is dynamically sealed relative to the sealing ring 206.

Fig. 10 shows a perspective view of the seal ring 206 of fig. 7. Fig. 11 shows a cross-sectional view of the seal ring 206 of fig. 7.

Referring to fig. 10 and 11, the seal ring 206 has a structure in which an outer seal ring 2061 on which an outer wall of the seal ring 206 is located, a middle seal ring 2062 connected to the outer ring 2061, and an inner seal ring 2063 contacting an outer wall of the sleeve 205. The cross-sectional shape of the outer seal ring 2061, the middle seal ring 2062, and the inner seal ring 2063 is substantially "i" shaped, a ring of ribs 2064 is provided inside the outer seal ring 2061 and the middle seal ring 2062, the specific cross-sectional shape of the ribs 2064 is "7" shaped, and the specific cross-sectional shape of the inner seal ring 2063 is "W" shaped, so that the inner seal ring 2063 has two seal portions 2066 that contact the casing 205. Of course, a snap spring or an annular spring 2065 is sleeved on the corresponding contact point of the inner seal ring 2063, so as to ensure that the inner seal ring 2063 is tightly contacted with the sleeve 205. Referring to fig. 9, in order to reduce the wear of the sleeve 205 when the sleeve 205 rotates synchronously with the balance shaft 20, a wear-resistant coating 2031 is disposed on the sleeve 205, the wear-resistant coating 2031 is a diamond-like coating, and the wear-resistant coating 2031 improves the wear resistance of the first shaft body 211, ensures the sealing performance of the sealing ring 205 on the first shaft body 211, and improves the service life of the engine 16.

Fig. 12 is a front view of the piston 40 and the connecting rod 401 in fig. 1.

In addition to driving the water pump 32 on the engine 16, the crankshaft 60 is driven primarily by the crankshaft 60 under inertia to move the piston 40 upward. Referring to fig. 12, the piston 40 is connected to the crankshaft 60 through a connecting rod 401, so that the crankshaft 60 drives the connecting rod 401, and thus the connecting rod 401 pushes the piston 40 upward, and the kinetic energy generated after the fuel is burned in the combustion chamber pushes the piston 40 downward. The piston 40 is a forged piston, and the piston 40 includes two parts, namely a piston head 41 and a piston skirt 42, and the piston head 41 and the piston skirt 42 are integrally formed. The piston skirt 42 is formed with pin holes that connect to connecting rods of the crankshaft.

The length of an axis along the height direction of the piston 40 is L alpha, the diameter of the cross section of the piston 40 is L phi, and the ratio of L alpha to L phi is 0.30-0.40: 1.0. The diameter of the piston 40 is 108mm, and the height of the piston 40 is 37 mm. Which reduces the height of the piston 40 to reduce the frictional force of the piston 40 sliding on the cylinder wall of the engine 16, while the piston 40 has a light weight and a small weight, achieving a high efficiency of the piston 40 moving back and forth in the cylinder of the engine 16, and a stronger power output of the engine 16.

In addition, referring to fig. 13, two pin bosses 43 having pin holes 430 are provided at a middle portion of the piston 40, with a gap remaining between the two pin bosses 43, and an upper end of the connecting rod 401 is located in the gap. Connecting ribs 431 are arranged on the left side and the right side of the pin hole 430 of each pin boss 43, one end of each connecting rib 431 is connected with the pin boss 43, the other end of each connecting rib 431 extends to the bottom of the piston head 41 in an upward inclined mode from the lower end part of the pin boss 43, and one end of each connecting rib 431 is connected with the pin boss 43, and the other end of each connecting rib 431 is connected with the piston skirt at the bottom of the piston 40; and each of the connecting ribs 431 is substantially triangular, i.e., the connecting ribs 431 have an arc-shaped line. The connecting ribs 431 are part of the piston 40, and the connecting ribs 431 reinforce the strength of the pin bosses 43 on the piston 40, thereby improving the strength of the piston 40.

Referring also to fig. 13, in order to increase the strength of the piston 40, two ribs 433 are provided between the two pin bosses 43, the ribs 433 being provided on both right and left sides of the pin hole 430. The reinforcing rib 433 strengthens the connection strength between the two pin bosses 40, improves the strength of the piston 40, and ensures that the piston 40 does not deform during working and has high stability. A square hole is cut in the middle of the reinforcing rib 433 to form a lubricating oil hole 4330. Lubricating oil flows through the lubricating oil hole 4330 to lubricate the connecting rod 401 in the pin hole 430, so that abrasion is reduced.

Referring to fig. 12 and 13, two air ring grooves 411 for mounting air rings are formed in the upper portion of the piston 40 in this order from top to bottom. An oil ring groove 412 is provided below the gas ring groove 411, and the oil ring groove 412 is opened with a plurality of oil holes 4120 in the circumferential direction. The lubricating oil on the cylinder wall of the engine 16 enters between the two piston skirts 42 of the piston 40 from the oil holes 4120. The oil ring 413 is sleeved on the oil ring groove 412, and the oil ring 413 scrapes lubricating oil on the cylinder wall of the engine 16 into the oil hole 4120, so that an oil return effect is realized, the engine 16 is prevented from combusting the engine oil, the lubrication of parts in the engine 16 is kept, and the abrasion is reduced. Referring to fig. 12, the inner wall of the oil ring 413 is recessed outward to form a housing cavity 4130, a supporting spring 4131 is disposed inside the housing cavity 4130, the supporting spring 4131 is an annular spring, the supporting spring 4131 supports the oil ring 413 to keep the oil ring 413 in close contact with the cylinder wall of the engine 16 to scrape off the lubricating oil on the cylinder inner wall of the engine 16, the oil scraping effect of the oil ring 413 is ensured, and when the oil ring is mounted, only two parts need to be mounted, and the mounting efficiency of the oil ring 412 is improved.

Referring to fig. 12 and 13, a circle of oil scraping collars 4133 with gradually reduced thickness extend from the upper portion of the outer wall of the oil ring 413 and the lower portion of the oil ring 413 respectively in a direction away from the inner wall of the oil ring groove 412, a gap is reserved between the two oil scraping collars 4133 to form an oil scraping groove 4135, a plurality of oil inlets 4134 are formed in the bottom of the oil scraping groove 4135, and the lubricating oil scraped by the oil scraping collars 4133 flows into the oil inlets 4134, then flows through the supporting spring 4131, and then flows into the piston 40 through the oil hole 4120. Referring also to fig. 12, the outer wall of the oil ring 413 is coated with a diamond-like coating 4136, and the diamond-like coating 4136 improves the wear resistance of the oil ring 40.

Fig. 14 shows a perspective view of the coupling of the crankshaft 60 and the flywheel 51 of the magneto in the engine 16. Fig. 15 is a sectional view taken along the axis C-C of fig. 14, and a partial view taken at B of fig. 15 in fig. 16. Fig. 17 shows an exploded view of fig. 15.

Referring to fig. 14 and 15, crankshaft 60 not only moves piston 40, but also acts as the primary shaft for magneto 50 on engine 16, driving magneto 50 into operation. The magneto 50 includes a magneto rotor (not shown) and a flywheel 51 that is housed outside the magneto rotor. The flywheel 51 comprises a magnetic isolation plate 511 close to the crankshaft 60, the edge of the magnetic isolation plate 511 extends towards the direction far away from the crankshaft 60 to form a circle of cylindrical outer cover 512, and a circle of gear teeth 513 are arranged on the outer wall of the overlapped part of the outer cover 512 and the magnetic isolation plate 511. A circular hole is formed in the middle of the magnetic isolation plate 511, the circular hole extends in a direction away from the crankshaft 60 to form a hollow truncated cone-shaped flywheel core 514, the end of the crankshaft 60 is inserted into the flywheel core 514, and the flywheel core 514 is pressed by a fixing bolt 52 connected with the crankshaft 60, so that the flywheel 51 and the crankshaft 60 are fixed.

Referring to fig. 16 and 17, the end of the flywheel core 514 away from the crankshaft 60 extends a circle toward the center of the circle to form a bent portion 515, and the bent portion 515 contacts with the washer on the fixing bolt 52 to increase the friction between the fixing bolt 52 and the flywheel core 514, so as to fix the flywheel 51 firmly.

Specifically, one end of the crankshaft 60 near the flywheel 51 is provided with a first connecting section 601 and a second connecting section 602 with the thickness gradually decreasing towards the flywheel 51, a connecting part from the first connecting section 601 to the second connecting section 602 is provided with a step, the thickness of the first connecting section 601 is larger than that of the second connecting section 602, and when the flywheel 51 is installed, the flywheel wheel core 514 is sleeved on the second connecting section 602. A blind bore 61 is drilled in the crankshaft 60, the depth of the blind bore 61 being approximately the sum of the length of the axis of the first connecting section 601 and the length of the axis of the second connecting section 602. The inner wall of the blind hole 61 corresponding to the first connecting section 601 is provided with threads, while the inner wall of the blind hole 61 corresponding to the second connecting section 602 is smooth, and when the fixing bolt 52 fixes the flywheel 51, the threads on the fixing bolt 52 are engaged with the threads in the blind hole 61. When the fixing bolt 52 is connected to the crankshaft 60, the second connecting section 602 having a relatively small thickness is avoided, the thinnest portion of the crankshaft 60 is not stressed, and the engine 16 of the crankshaft 60 operates stably.

In addition, referring to fig. 17 together, the fixing bolt 52 has a bolt head 522 and a bolt shank 521 formed by a smooth section 5211 and a threaded section 5212, the bolt head 522 and the bolt shank 521 are integrated, the threaded section 5212 on the bolt shank 521 is screwed with the internal thread of the blind hole 61, and the smooth section 5211 of the bolt shank 521 corresponds to the smooth section of the inner wall of the blind hole 61, so that the second connecting section 602 of the crankshaft 60 is not stressed and the crankshaft is not deformed. Of course, in some embodiments, the entire section of the bolt shaft may be externally threaded. The smooth section of the bolt rod is not contacted with the inner wall of the blind hole or only attached together, so that no interaction force exists between the bolt rod and the thinnest part of the crankshaft, and the crankshaft is not easy to deform and has good durability.

Fig. 18 is a perspective view showing a drive gear of an oil pump of the engine 16, and the drawing specifically shows only the drive gear, and does not show other structures of the oil pump.

Referring to fig. 18, the engine 16 further includes an organic oil pump, the organic oil pump is provided with a driving gear 100, the driving gear 100 includes a disk and a plurality of gear teeth arranged on the disk, wherein the disk is in a shape of a disk, and the gear teeth are arranged along a circumferential direction of the disk in an array at an edge of the disk.

The middle of the driving gear 100 is provided with a sleeve opening 101 with the diameter slightly smaller than that of the driving gear 100, and the circle center of the sleeve opening 101 and the circle center of the driving gear 100 are on the same axis. The driving gear 100 is provided with a pin hole 102 penetrating through the driving gear 100, wherein the pin hole 102 is communicated with the sleeve opening 101, so that the pin hole 102 and the sleeve opening can be in a U-shaped cross section, therefore, under the structure, the requirements of the driving gear 100 on the distance between pin rods matched with the pin hole and the diameter of the pin rods can be reduced, and the related performance of the oil pump cannot be influenced even if the distance between the two pin rods has an inward error. The two pin holes 102 are symmetrical along the central axis of the drive gear 100. The driving gear 100 is further provided with an annular groove 103, the annular groove 103 and the trepan boring 101 are concentrically arranged, and the distance from the annular groove 103 to the circle center of the driving gear 100 is larger than the distance from the inner wall of the pin hole to the circle center of the driving gear.

In the scheme, the above embodiments can be combined arbitrarily, and certainly can be combined with the prior art arbitrarily; all patents and publications mentioned in the specification of the utility model are indicative of the techniques disclosed in the art to which this invention pertains and are intended to be applicable. All patents and publications cited herein are hereby incorporated by reference to the same extent as if each individual publication was specifically and individually indicated to be incorporated by reference. The utility model herein may be practiced in the absence of any element or elements, limitation or limitations, which limitation or limitations is not specifically disclosed herein. The terms and expressions which have been employed herein are used as terms of description and not of limitation, and there is no intention in the use of such terms and expressions of excluding any equivalents of the features shown and described, but it is recognized that various modifications and changes may be made within the scope of the utility model and the claims which follow. It is to be understood that the embodiments described herein are preferred embodiments and features and that modifications and variations may be made by one skilled in the art in light of the teachings of this disclosure, and are to be considered within the purview and scope of this invention and the scope of the appended claims and their equivalents.

Claims

1. The oil pump gear is characterized in that the oil pump gear is a driving gear arranged on an oil pump and comprises a disc-shaped wheel disc, and a plurality of wheel teeth are arranged on the edge of the wheel disc along the circumferential direction;

2. The oil pump gear according to claim 1, wherein the pin hole is formed in a "U" shape in cross section.

3. The oil pump gear according to claim 1, wherein there are at least two pin holes, and the two pin holes are symmetrically arranged with respect to the sleeve hole.

4. The oil pump gear according to claim 1, wherein the pin hole penetrates the drive gear in a thickness direction of the drive gear.

5. The oil pump gear of claim 1, wherein the drive gear further comprises an annular recess.

6. The oil pump gear according to claim 5, wherein the annular groove is concentrically arranged with the trepan.

7. The oil pump gear of claim 5, wherein the distance from the annular groove to the center of the driving gear is greater than the maximum distance from the inner wall of the pin hole to the center of the driving gear.

8. A motorcycle engine comprising an oil pump gear according to claims 1-7, said engine further comprising

A cylinder block;

a cylinder head connected to the cylinder block;

a cylinder head cover connected with the cylinder head;

a crankshaft;

a connecting rod;

a piston coupled with the crankshaft through the connecting rod;

a balancing device associated with the crankshaft.