WO2007101385A1

WO2007101385A1 - A lubricating mechanism of an engine

Info

Publication number: WO2007101385A1
Application number: PCT/CN2007/000272
Authority: WO
Inventors: Henglin Xiao
Original assignee: Wuxi Kipor Power Co., Ltd
Priority date: 2006-03-08
Filing date: 2007-01-25
Publication date: 2007-09-13
Also published as: CN100567708C; CN1821555A

Abstract

The application relates to a lubricating mechanism of an engine. The lubricating mechanism includes an engine body (1), an engine box (1a) and a cylinder cover (1b). The engine body (1) is composed of the engine box (1a) and the cylinder cover (1b) which are integral each other, the valve operative room (9) is located between the engine body (1) and a cowl (2). A chain tensioner (18) is installed in a crankcase (15). The valve operative room (9) has an oil groove (36) therein, and two end openings of the oil groove (36) open to the valve operative room (9).

Description

Lubrication structure of engine

The invention relates to a lubricating structure of an engine, in particular to lubricating oil to various parts of a valve operating system, and belongs to the technical field of power plants.

Background technique

Before the present invention was made, in the prior art, the lubricating structure of the engine usually adopts a cam top-mounted mechanism. This structure eliminates the use of a chain or a toothed belt for the components such as the tappet and the push rod, and has the advantages of less reciprocating parts. The main mechanism of the tappet and the push rod is eliminated, and the vibration caused by the reciprocating mass inertia force is small at high speed, which is suitable for high-speed operation of the engine. However, this structural disadvantage is that it is difficult to provide sufficient lubricating oil between the support shaft and the intake and exhaust cam and the driven wheel to cause wear of the parts and shorten the service life.

Chinese Patent Application No.: 02104779. 0 In the lubricating structure disclosed, the lubricating oil supply in the crankcase is carried by the transmission belt to the valve operating system, and is separated from the transmission belt by the centrifugal force at the portion of the transmission belt surrounding the driven wheel. The separated lubricating oil collides with the splash ribs and atomizes. Due to the blockage of the belt baffle and the decompression device on the driven wheel, the lubricating oil supplied to the contact portion between the intake and exhaust cam and the valve rocker arm is insufficient.

Summary of the invention

The object of the present invention is to overcome the above-mentioned deficiencies, thereby providing a driven sprocket that can be freely rotated by the crankshaft timing sprocket to control the opening of the intake and exhaust valves, and the sprocket transmission mechanism is automatically tensioned by the chain inside the crankcase. The device guides and tensions the synchronous transmission device; automatically compensates for looseness and tooth skipping during the chain transmission process; the inner hole of the chain synchronous transmission device has an oil groove, and an oil groove is provided at the bottom of the engine body opening at the bottom of the valve operating room, The oil mist form and the splash lubrication system simultaneously provide lubrication between the intake and exhaust cams and the driven sprocket and the support shaft, thereby enabling the lubricating oil to be uniformly supplied to the lubricating structure of the engine of each part of the valve operating system.

The main solution of the invention is achieved in this way:

The present invention includes a body 1 of an engine, characterized in that the body 1 of the engine is composed of an engine casing la and a cylinder head lb, and the overhead cam transmission mechanism 38 is supported by the support shaft 8 in the valve operating chamber 9, the valve operating chamber 9 a cover 2 formed on the engine body 1 and connected to the engine body Between the two ends of the support shaft 8 is supported in the shaft hole lc of the upper part of the cylinder head lb, and an annular sealing ring 39 is arranged between the shaft hole lc and the shaft, and the outer end surface of the shaft is a flat plane 40, and the flat plane 40 is pressed In the lower part of the pressure plate 2a of the cylinder head cover 2, the valve operating system 6 is installed in the valve operating chamber 9, and the crankshaft 12 is supported in the crankcase 15 through the two ends bearings 13, 14, and the crankcase 15 is provided with lubricating oil 17, and the chain tensioning device 18 is installed in the crankcase 15, the inner opening of the valve operating chamber 9 is provided with an oil groove 36. Both ends of the oil groove 36 are simultaneously opened in the valve operating chamber 9, and an oil groove 37 is provided at the upper portion of the cylinder head lb, and the upper end is open at the bottom of the valve operating room 9. The bottom end is closed, the oil groove 37 is in communication with the oil groove 36, and the pressure reducing device 41 is mounted on the side of the overhead cam transmission mechanism 38.

The overhead cam transmission mechanism 38 of the present invention comprises a crankshaft timing sprocket 3, a driven sprocket 4, a toroidal roller chain 5, an intake and exhaust cam 7, a support shaft 8, and a crankshaft 12, and the toroidal roller chain 5 surrounds the crankshaft. On the hour sprocket 3 and the driven sprocket 4, the intake and exhaust cams 7 are mounted on the support shaft 8, and the crankshaft timing sprocket 3 is fixed to the crankshaft 12.

The valve operating system 6 of the present invention includes an intake valve rocker arm 10, an exhaust valve rocker arm 11, an intake valve rocker arm 10, and an exhaust valve rocker arm 11 mounted on the body 1 of the engine.

The chain tensioning device 18 of the present invention comprises a chain pallet 19, a chain pressing plate 20, a tension spring 21, a clamping block 22, a spring pin 23, a circular arc groove 24, a concave corner 25, a convex circular arc 26, a convex angle 27, a transmission passage 28, square hole 29, the chain bracket 19 is fixed on the block 22, the chain plate 19 is provided with a circular arc groove 2 and a concave corner 25, and the circular groove 24 and the concave corner 25 are stuck on the block 22 On the arc 26 and the lobes 27, the upper portion thereof penetrates into the transmission passage 28 C, the chain pressing plate 20 is fixed by the spring pin 23, and the tension spring pin 23 is fixed to the body 1 through the tension spring 21 and the chain pressing plate 20, and is tensioned. The spring 21 is hooked into the square hole 29 of the chain clamp 20 and the other end is blocked on the stopper 30.

The pressure reducing device 41 of the present invention includes a pressure reducing fly block 42, a pressure reducing spring 43, a spring pin 44 and a pin shaft 45 which is mounted in the shaft hole 46 of the overhead cam gear mechanism 38 and is driven by the overhead cam. The mechanism shaft hole 46 rotates, and the pressure reducing spring 43 is fixed to the overhead cam gear mechanism 38 via the pin shaft 45, and the spring pin 44 is fixed to the overhead cam gear mechanism 38.

Compared with the prior art, the invention has the following advantages: the invention is simple, compact and reasonable; the engine body and the cylinder head are integrated; the engine uses a chain synchronous transmission, and the chain synchronous transmission is supported by a support shaft. In the upper valve operating room of the machine body, the driven sprocket can be freely rotated by the crankshaft timing sprocket. The opening and closing of the exhaust valve; the sprocket transmission mechanism guides and tensions the synchronous transmission device through a chain automatic tensioning device in the crankcase; automatically compensates for looseness and tooth skipping during the chain transmission process; An oil groove is provided in the hole, and an oil groove is provided in the upper opening of the engine body and the bottom of the valve operating room, and the lubrication between the intake and exhaust cam and the driven sprocket and the support shaft is provided by the oil mist form and the splash lubrication system. The lubricating oil is hooked to each part of the valve operating system; the heat generated by the high speed rotation of the intake and exhaust cam driven sprocket is suppressed, and the engine is ensured to work reliably, and the overhead cam transmission mechanism further includes a pressure reducing device, the decompression The unit is located on the other side of the valve rocker arm to ensure adequate lubrication of the contact between the intake and exhaust cam and the valve rocker arm.

DRAWINGS

Figure 1 is a front view of the structure of the present invention:

Figure 2 is a longitudinal cross-sectional view showing the structure A to A of the present invention.

Figure _{3 is a} transverse cross-sectional view of the structure B to B of the present invention.

Figure 4 is an outline view of the overhead cam drive mechanism of the present invention.

detailed description

The invention will be further described below in conjunction with the embodiments of the drawings:

The invention mainly comprises an engine body 1, an engine casing la, a cylinder head lb, a shaft hole lc, a cover 2, a pressure plate 2a, a crankshaft timing sprocket 3, a driven sprocket 4, a toroidal roller chain 5, and a valve operation. System 6, intake and exhaust cam 7, support shaft 8, valve operating chamber 9, intake valve rocker arm 10, exhaust valve rocker arm 11, crankshaft 12, bearings 13, 14, crankcase 15, box cover 16, lubricating oil 17. Chain tensioning device 18, chain pallet 19, chain clamp 20, tension spring 21, block 22, circular groove 24, concave corner 25, convex arc 26, lobes 27, transmission channel 28, square hole 29. Stop 30, arc 31, intake and exhaust valves 32, 33, sides 34, 35, oil grooves 36, 37, overhead cam drive mechanism 38, pressure reducing device 41, pressure relief block 42, pressure reducing spring 43 The spring pin 44, the pin shaft 45, the shaft hole 46 and the like are composed.

In the drawings 1-4, the body 1 of the four-stroke engine is mainly included, and the body 1 is a structure of an engine casing la and a cylinder head lb-body. The driven sprocket 4 and the intake and exhaust cam 7 are of a unitary structure. The overhead cam transmission mechanism 38 includes a crankshaft timing sprocket 3, a driven sprocket 4, a toroidal roller chain 5, an intake and exhaust cam 7, a support shaft 8, and a crankshaft 12. The toroidal roller chain 5 surrounds the crankshaft timing sprocket 3 and the driven sprocket 4, and the intake and exhaust cam 7 is mounted on the support shaft 8, and the crankshaft timing sprocket 3 is fixed to the crankshaft 12. The overhead cam transmission mechanism 38 is rotatably supported by the valve operating chamber 9 via a support shaft 8. The valve operating chamber 9 is formed by combining the cylinder head 1b of the engine and the cover 2, and both ends of the support shaft 8 are supported in the shaft hole lc of the upper portion of the cylinder head lb, and a ring is formed between the support shaft hole lc and the shaft. The seal ring 39, the outer end surface of the support shaft 8, is a flat flat surface 40 which is pressed against the lower portion of the pressure plate 2a of the cylinder head cover 2, thereby preventing the support shaft 8 from rotating itself. The valve operating system 6 includes an intake valve rocker arm 10 and an exhaust valve rocker arm 11, which are respectively mounted on the body 1 of the engine. The crankshaft 12 is supported in the crankcase 15 by the two ends bearings 13, 14 and is mounted on the body 1 of the engine via the piston 47 and the connecting rod 48, and is freely rotatable in the crankcase 15, which is constituted by the casing lb and The box cover 16 is assembled. The crankcase 15 is provided with a lubricating oil 17, and the chain tensioning device 18 is mounted in the crankcase 15. The chain tensioning device 18 includes a chain bracket 19, a chain pressing plate 20, and a tension spring 21. The chain bracket 19 is fixed on a block 22, and the chain bracket 19 is provided with a circular arc groove 24 and a concave corner 25, and the circular arc groove 24 and the concave corner 25 are firmly stuck on a convex circle of the block 22. On the arc 26 and a lobe 27, the upper portion thereof penetrates into the transmission passage 28; the chain pressing plate 20 is fixed by a tension spring pin 23 and is freely swingable, and the tension spring pin 23 passes through the tension spring 21 and the chain pressing plate 20 It is fixed on the body 1, and the tension spring 21 is hooked into the square hole 29 of the chain pressing plate 20, and the other end is blocked on the stopper 30. The intake and exhaust cam 7 and the driven sprocket 4 are integrally formed in the valve operating chamber 9, and the inner hole is provided with an oil groove 36; both ends of the oil groove 36 are simultaneously opened in the valve operating chamber 9, and an oil groove is arranged at the upper portion of the cylinder head lb. 37, the upper end is open at the bottom of the valve operating room, and the bottom end is closed. Its oil groove 37 can communicate with the oil groove 36. The overhead cam transmission mechanism 38 is laterally mounted with a pressure reducing device 41 including a pressure reducing fly block 42, a pressure reducing spring 43, a spring pin 44 and a pin shaft 45, and the pressure reducing flying block 42 is mounted on the overhead cam drive The mechanism 38 is axially bored 46 and is freely rotatable within the overhead cam drive shaft bore 46. The pressure relief spring 43 is secured to the overhead cam drive 38 by a pin 45, and the spring pin 44 is secured to the overhead cam drive mechanism. 38.

The working principle and working process of the invention:

The operation of the present invention is such that when the engine crankshaft 12 is rotated counterclockwise along the arc 31, the crankshaft timing sprocket 3 drives the toroidal roller chain 5 for rotating the crankshaft 12 at a gear ratio of 1:2. The power is transmitted to the driven sprocket 4, thereby driving the intake and exhaust cam 7 to rotate along the support shaft 8, and the intake and exhaust cam 7 is in sliding contact with the intake and exhaust valve rockers 10, 11 when the intake and exhaust cam 7 rotates. Thereby, the intake valve rocker arm 10 and the exhaust valve rocker arm 11 are rotated, thereby controlling the intake and exhaust valves 32, 33 to open. When the engine crankshaft 12 rotates counterclockwise along the arc 31, a 34-way transport of the toroidal roller chain 5 The line is in tension, the side is guided by a chain plate 19, and the other 35 side is pushed by the elastic force of the tension spring 21 to push the chain plate 20, under the elastic force of the tension spring 21, the chain plate 20 Always close the 35 sides of the toroidal roller chain 5. This structure can not only automatically tension the chain, prevent the chain from jumping and dislocating during the transmission process, and can automatically compensate for the elongation of the chain during long-term operation, and adopts automatic adjustment as a built-in sprocket transmission mechanism. It is simple, reliable and durable, and is suitable for all speed engines without manual adjustment. At the same time, when the engine is rotated at a high speed, the lubricating oil 17 adheres to the annular roller chain 5 and moves with the annular roller chain 5, and the annular roller chain 5 can supply the lubricating oil 17 in the crankcase 15 to the valve operating chamber 9. The lubricating oil 17—partly enters the synchronous chain oil sump in the form of oil mist, and the other part of the lubricating oil splashed into the valve operating room through the splash lubrication system falls down to the bottom of the valve operating room, and falls into the oil sump 37 by gravity to guide the cam timing transmission. The inner bore of the sprocket oil groove 36 is further lowered from the other end of the oil groove 36 to ensure a certain amount of lubrication is supplied to the area between the intake and exhaust cam and the driven sprocket and the support shaft, thereby reducing heat generated by high-speed rotation. At the same time, when the overhead cam transmission mechanism 38 is operated at a certain rotation speed when the engine is started, the decompression flying block 42 can automatically return to the exhaust valve pair through the exhaust valve rocker arm 10 under the elastic force of the decompression spring 43. The engine acts as a decompression. When the engine is running at a high speed, the decompression flying block 42 can overcome the elastic force of the decompression spring 43 and operate the engine under the limit of the spring pin 44. The pressure reducing device is located on the other side of the valve rocker arm to ensure sufficient lubrication of the contact portion between the intake and exhaust cam and the valve rocker arm.

In general, as a built-in automatic adjustment sprocket transmission mechanism, the invention has a compact structure, good automatic adjustment effect, and ensures sufficient lubrication effect, reliability and durability. The invention is also widely applicable to any four-stroke overhead cam engine.

Claims

1. A lubricating structure of an engine, comprising an engine body (1), an engine casing (la), and a cylinder head (lb), characterized in that the engine body (1) is composed of an engine casing (la) and a cylinder head ( Lb) constitutes a one-piece structure, the overhead cam drive mechanism (38) is supported by the support shaft (8) in the valve operating room

(9) inside, the valve operating room (9) is between the engine body (1) and the cover (2) connected to the engine body; both ends of the support shaft (8) are supported by the shaft hole at the upper part of the cylinder head (lb) In (lc), an annular seal ring (39) is provided between the support shaft hole (lc) and the shaft, and the outer end surface of the support shaft (8) is a flat plane

(40), the flat plane (40) is pressed against the lower part of the pressure plate (2a) of the cylinder head cover (2), the valve operating system (6) is installed in the valve operating room (9), and the crankshaft (12) is passed through the bearings at both ends (13) , 14) supported in the crankcase (15), the crankcase (15) is filled with lubricating oil (17), the chain tensioning device (18) is installed in the crankcase (15), and the valve operating chamber (9) is opened. There is an oil groove (36), and both ends of the oil groove (36) are open in the valve operating chamber 9. An oil groove (37) is arranged at an upper portion of the cylinder head (lb), and an upper end is open at the bottom of the valve operating room (9), and the bottom end is closed. The oil groove (37) is in communication with the oil groove (36), and the overhead cam transmission mechanism (38) is provided with a side pressure reducing device (41).

2. The lubricating structure of an engine according to claim 1, wherein said valve operating system (6) comprises an intake valve rocker arm (10), an exhaust valve rocker arm (11), and an intake valve rocker arm. (10) The exhaust valve rocker arm (11) is mounted on the engine block (1).

3. The lubricating structure of an engine according to claim 1 or 2, wherein said overhead cam transmission mechanism (38) comprises a crankshaft timing sprocket (3), a driven sprocket (4), and a ring rolling Sub-chain (5), intake and exhaust cam (7), support shaft (8), crankshaft (12), toroidal roller chain (5) around the crankshaft timing sprocket (3) and the driven sprocket (4) Upper, the intake and exhaust cam (7) is mounted on the support shaft (8), and the crank timing sprocket (3) is fixed to the crankshaft (12).

4. The lubricating structure of an engine according to claim 3, wherein said chain tensioning device (18) comprises a chain pallet (19), a chain pressing plate (20), a tension spring (21), and a block. (22), spring pin (23), circular groove (24), concave angle (25), convex arc (26), bulge (27), transmission channel (28), square hole (29), chain holder The plate (19) is fixed on the block (22), and the chain plate (19) is provided with a circular groove (24) and a concave angle (25), and the circular groove (24) and the concave angle (25) are stuck on the card. Piece

(22) On the convex arc (26) and the bulge (27), the upper part penetrates into the transmission channel (28). The chain pressing plate (20) is fixed by a spring pin (23), and the tension spring pin (23) is fixed to the body (1) through the tension spring (21) and the chain pressing plate (20), and the tension spring (21) is terminated. Hook into the square hole (29) of the chain clamp (20) and the other end on the stop (30).

5. The lubricating structure of an engine according to claim 4, wherein said pressure reducing device (41) comprises a pressure reducing block (42), a pressure reducing spring (43), a spring pin (44) and a pin shaft. (45), the decompression flying block (42) is installed in the shaft hole (46) of the overhead cam transmission mechanism (38), and rotates in the shaft hole (46), and the pressure reducing spring (43) passes through the pin shaft (45) The spring pin (44) is fixed to the overhead cam drive (38).