TW530114B - Handheld type four-cycle engine - Google Patents

Abstract

In a handheld type four-cycle engine, a valve operation mechanism includes a camshaft rotatably supported in a cylinder head so as to open and close an intake valve and an exhaust valve and a timing transmission placed on one side outside an engine main body and providing association between a crankshaft and the camshaft, and a centrifugal clutch for power output is mounted on the crankshaft on the opposite side outside the engine main body. The timing transmission and the centrifugal clutch being positioned at the two ends of the crankshaft improves the weight balance, the centre of gravity of the engine can be made as close to the central part of the crankshaft as possible, which, together with the reduced weight, can enhance the operability of the engine.

Description

530114 A7 B7 V. Description of the invention (2 In view of this, the purpose of the present invention is to provide an engine that makes the engine ------------------------ —— (Please read the precautions on the back before filling this page) The aforementioned handheld four-stroke engine with small size and light weight for good workability. 一一 叮 |: Line 丨 In order to achieve the above purpose, the handheld of the present invention Type four-stroke engine includes: an engine body composed of a crank case having a crank chamber, a cylinder block having a cylinder bore, and a cylinder head having an air inlet and an exhaust port; and one supported by the crank case and housed in the A crankshaft in a crank chamber; a piston embedded in the cylinder bore while being connected to the crankshaft; an intake valve and an exhaust valve installed on the cylinder head to open and close one of the intake and exhaust ports ; A valve mechanism that can be linked to the rotation of the crank shaft to drive the intake valve and the exhaust valve to open and close; a power output mechanism provided at the end of the crank shaft protruding outside the engine body; and a fuel tank. It is characterized in that the valve actuating mechanism is supported by a cylinder head, In a state of free rotation, the camshaft that can drive the aforementioned intake valve and exhaust valve to open and close, and a camshaft that is arranged on the engine body on the opposite side to the power output mechanism so that the crankshaft and camshaft are connected to each other. A dry timing transmission is formed, and a cooling blade for transmitting cold wind to the engine body may be provided on the engine body, and a power output mechanism with a diameter larger than that of the crank shaft between the engine body and the power output mechanism is installed. The large flywheel is mounted on the crank shaft, and supports the fuel tank on the same side as the timing transmission of the engine body. Moreover, the aforementioned power output mechanism corresponds to a centrifugal clutch described later. According to this first Features: When the cylinder block is placed in the middle, and the timing gear output mechanism is installed at both ends of the crankshaft, the weight of the two ends of the crankshaft is well balanced, and the center of gravity of the engine can be as close to the crankshaft as possible. This paper size applies the Chinese National Standard (CNS) A4 specification (210X297 public love) 5. The description of the invention (3) The central part, so that it can complement the lightweight, This improves the workability of the engine. Furthermore, during the operation of the engine, the load from the timing transmission and the drive shaft can be dispersed at both ends of the crank shaft, thereby avoiding the concentration of the load on the crank shaft and its bearings, thereby improving It has the durability. In addition, it is not necessary to try to avoid the engine enlargement caused by the flywheel, and to hinder the power output mechanism due to the rotation of the cooling blades, and it is possible to reliably supply cold air to the engine body. Cooling performance and the fuel tank is arranged opposite to the flywheel, the center of gravity of the engine will be close to the center of the crank shaft, and the workability of the engine will be further improved. On the basis of the first feature, the present invention The timing transmission device can be constructed as a dry type and isolated from the crank chamber, which is the second feature of the present invention. According to this second feature, there is no need to set a room particularly on the side wall of the engine body to accommodate the timing As a result of the transmission, the engine body can be thinned and miniaturized, and the overall weight of the engine can be significantly reduced. The present invention is based on the first or second feature, and can be arranged on the outside of the timing transmission _ an oil tank for storing lubricating oil inside the engine body, and at the same time, supports the oil tank on the engine body, This is the third feature of the present invention. According to this third feature, the fuel tank covers at least a part of the timing transmission device to protect the transmission device. , Furthermore, the present invention is in the first! Based on the characteristics, the timing mechanism can be arranged on the-outside of the engine body and connected to the-end of the crank shaft 'and the rotational force of the driven side of the timing transmission can be transmitted The intake valve and the exhaust valve are constituted by a cam device as one of their opening and closing forces. The fifth valve 530114, invention description (4), and the first valve actuating chamber that houses this timing transmission is connected to the fuel tank as a whole. 'Placer: And the second moving chamber containing at least a part of the cam gear is formed on the Λ cylinder head' and is fixed on the crankshaft-facing the timing, the oil throwing core placed on the move 'should The oil slinger is used to stir the oil stored in the fuel tank to cause it to scatter and form an oil mist to supply the second pumping chamber and crank chamber. This is the fourth feature of the present invention. According to this fourth feature, Because the fuel tank system is installed on the outside of one of the engine bodies, the same degree of the king body of the engine can be greatly reduced. And the first valve actuating chamber that houses the timing transmission device is integrally connected with the fuel tank, then-part of the timing transmission device It will be contained in the fuel tank, and the effect of miniaturizing the engine can be achieved In addition, the valve system's lubrication system is divided into two, one is to lubricate with the scattered oil in the fuel tank! The timing drive system in the valve chamber: the system, the other is the oil mist formed in the tank The system that lubricates the cam mechanism of the second valve operating chamber can reduce the burden of each lubrication system and evenly lubricate the entire valve operating mechanism. Moreover, the oil throwing rings fixed to the crank shaft are arranged in pairs and held. The timing transmission device does not impede the timing transmission device at this time, and the oil stored in the fuel tank can be effectively mixed and scattered to form an oil mist regardless of any running posture of the engine. The invention is based on the fourth feature, and a port can be provided on the crank shaft to supply the oil mist generated in the fuel tank to the crank chamber, and the open end of the port facing the fuel tank is arranged for timing transmission Between the split and the oil slinger, this is the fifth feature of the present invention. According to this fifth feature, the opening on the crank shaft faces the opening of the fuel tank. The paper size applies the Chinese national standard (⑽) A4 specification ( 210X297 mm) ......... ........-..... install ... (please read the precautions on the back before filling this page), can | -line 丨 530114 Description of the invention (/ end does not indicate the timing transmission device and The oil slinger forms an obstacle. Because it can be arranged at or near the center of the oil phase, the oil stored in the fuel tank can be prevented from flowing directly into the port regardless of the engine's running posture. ^ Also, the present invention is in the fourth feature On the basis, a leather τ guide cylinder capable of accommodating the timing transmission is integrally connected with the fuel tank, and the belt guide cylinder is protruded from the central side of the fuel tank at the open end facing the fuel tank, and is structured to be inconsistent The engine is inverted or placed horizontally, and the open end can be exposed on the liquid surface of the stored oil, which is the sixth feature. According to this sixth feature, the overall height of the engine can be reduced, and the increase in the width of the engine can be suppressed as much as possible. , So the miniaturization of the engine can be achieved. And whether the 々 engine is upside down or sideways, the belt guide 1 of the timing transmission device can be exposed on the liquid level of the oil storage at the open end facing the fuel tank. The inflow of the transmission device can prevent excessive oiling of the timing transmission device, and at the same time, the oil in the fuel tank can be maintained in a constant amount. On the basis of the fourth feature, the present invention allows the other end of the crankshaft to be driven from the tank and the timing transmission of the valve mechanism in the tank; the crankshaft is described as follows The oil in the oil tank lubricates the timing transmission device. This is the seventh feature of the present invention. According to this seventh feature, there is no need to provide a 1 on the side wall of the engine body to accommodate the timing transmission, and because the fuel tank is arranged on the side, the overall engine ’s height is reduced. Therefore, the side wall of the engine body can be thinned and miniaturized. And achieved the goal of a substantial weight reduction for the entire bow I engine. 1. The power output mechanism arranged on one side of the engine body, and the timing transmission device and fuel tank arranged on the other side can form a good balance between the weight of the two ends of the crank shaft, and make the paper size of the engine suitable for the country of China Standard (CNS) A4 specification (210X297 mm) (Please read the precautions on the back before filling this page)

-8- V. Description of the invention (6) The center of gravity should be as close as possible to the center of the shaft ‘so that it can complement weight reduction’ and improve the workability of the engine. Further, during the operation of the engine, the load from the timing transmission device and the power output mechanism can be distributed to both ends of the crank shaft, thereby avoiding the concentration of the load on the crank shaft and its bearings, thereby improving their durability. Furthermore, the timing transmission is directly lubricated with the oil in the fuel tank, which simplifies the lubrication system. In addition, the present invention is based on the seventh feature. As a cooling blade, a cooling fan having a larger diameter than the power output mechanism can be fixed on the crank shaft. This is the eighth feature of the present invention. According to this eighth feature, while increasing the air supply capacity of the cooling fan, it is possible to avoid the large size of the engine E as much as possible. In addition, the present invention is based on the eighth feature, and a cam mechanism can be arranged in the valve operating chamber on the cylinder head to transmit the rotation of the driven side of the timing transmission to the intake valve and the exhaust valve as its This is the ninth feature of the present invention, in which an oil mist forming device 'is connected to the crank shaft to generate oil mist in the fuel tank and supply the valve actuating chamber. According to this ninth feature, the lubrication system of the valve mechanism is divided into two, one is a system for lubricating the king transmission with oil in the oil tank, and the other is for lubricating the cam device with oil mist formed in the oil tank. This system can reduce the burden of each turbidity system, and can evenly lubricate the entire wide movement mechanism. Furthermore, the present invention is based on the first feature of the fourth feature, and the timing transmission structure of the valve movement mechanism can be constructed. Into a winding type with a winding member, at the same time the paper size of this winding applies the Chinese National Standard (CnS) A4 specification (210X297 public love) 530114

Description of the invention (The driving side of the component is set facing the fuel tank, and the fuel tank is provided with an oil flying formation device for generating oil and gas, so that it is stored inside (please read the precautions on the back first) Fill in this page) The stored oil is scattered to lubricate the front 诂 τ n taxi & attack timing transmission. In addition, an oil drop is protruded from the inner wall of the fuel tank to read the path, and then guide the same wall, so that when the engine falls down In order to induce the adhering oil Feimu to drip on Yu Khan, the timing transmission device facing the fuel tank ’s blade is the 10th feature of the present invention. According to the 10th feature of the beta sea, the engine is turned down When the state is running, the oil droplets attached to the oil droplet induction wall form oil droplets, and the driving side of the timing transmission device falls to the winding member, and the upper part of the winding member moves from the driving side to At the driven side, the oil droplets can be transported from the winding member to the driven side without being affected by the separation force, and the driven side can be reliably lubricated. • Ordering 丨 In addition, the aforementioned winding member is implemented with the present invention described later. The timing drive belt 25 in the example corresponds to

• Line I. On the basis of the first feature of the present invention, the valve actuating mechanism can also be formed across an oil tank installed outside the engine body for storing lubricating oil, and extended from the oil tank to above it. The i-th valve actuating chamber and a second valve actuating chamber formed in the cylinder head are arranged; and the oil tank and the crank chamber are communicated with each other through a port, and the crank chamber and the second valve actuating chamber are disposed between The oil delivery duct on the outside of the engine body is connected, and the second valve operating chamber and the fuel tank are connected by a return oil passage. Furthermore, the fuel tank is provided with a function to stir and disperse the stored oil to generate oil. The mist oil mist forming device is also provided with a transmission device connected to the oil delivery duct to transmit the oil mist in the oil tank to the oil delivery duct through the crank chamber, and the scattered oil in the oil tank can be used to lubricate the oil in the first valve moving chamber. The valve actuating mechanism is lubricated with oil mist transmitted from the oil delivery duct to the second valve actuating chamber. The paper size of the second valve actuating chamber is in accordance with China National Standard (CNS) A4 (210X297 public love) -10- 530114 A7 B7

V. Description of the invention (The valve actuating mechanism of S is the first feature of the present invention. According to this 11th feature, because of the connection with the r ocean and Shanzeng U 4 oil pipeline, it is arranged outside the engine body ... — (Please read the precautions on the back before filling in this page) side, the thickness of the engine body is not related to the existence of the guide ^ a β ^ S, and the goal of miniaturization of the engine body can be achieved, and the entire engine can be created It is lighter, and then, because the oil delivery pipe outside the engine body is exothermic ^, the cooling of the oil mist passing through the pipe can be promoted. And the lubrication system of the valve mechanism is divided into a lubricating oil tank with the scattered oil in the oil tank and the first i The system of timing transmission in the moving room, and a system that lubricates the valve moving mechanism in the second valve moving room with the oil mist transmitted to the second valve. Therefore, the two types of systems can be reduced. It can evenly lubricate the entire valve actuating mechanism. Order. And, no matter the engine is in any running position, the engine parts can be reliably lubricated by the use of oil flying or oil mist.: 线 — Again, this Invented on the basis of the Uth feature, it is also possible The transmission device is constituted by a valve device which can close the oil delivery conduit when the crank chamber is under negative pressure, and opens the conduit when it is under positive pressure. This is the twelfth feature of the present invention. According to the twelfth feature, it is unnecessary to The device is a special oil pump for circulating oil mist, so as to achieve the effect of simplification of the structure. In addition, on the basis of the U-th or 12th features, the invention can also use a bypass pipe to make the oil delivery conduit and the return oil channel phase Continuing, this is the thirteenth feature of the present invention. According to the thirteenth feature, the oil passage resistance from the oil delivery duct to the second chamber can be adjusted by appropriately selecting the oil path resistance of the bypass pipe.

-1U 530114 A7 I -------------______ 5. Description of the invention (9) " '-' Also, on the basis of the first feature of the present invention, the valve moving mechanism can also be A timing transmission device formed by driving a rotating member connected to a crank shaft, and a cam for transmitting the rotational force of the driven rotating member of the timing transmission device to the intake valve and the exhaust valve as its opening and closing force The valve body is provided on the side of the engine body to accommodate the timing transmission device, and the lower end of the valve room is provided with an oil mist forming device to store it. The oil tank which forms oil mist is provided with a second valve actuating chamber parallel to the first wide actuating chamber and accommodating the cam device on the upper part of the engine body; 2 oil circuit, and the oil mist formed in the oil phase from the tank through the first! The oil path, the crank chamber, and the second oil path return to the fuel tank by the i-th oil feeding device to constitute the third lubrication system, and the third oil path is connected to the first and second valves. 4. The fourth oil path connecting between the second wide moving chamber and the crank chamber, and the aforementioned second oil path, and the oil mist formed in the fuel tank passes through the fuel tank in order! The valve operating chamber, the third oil passage, the second valve operating chamber, the fourth oil passage, the crank chamber, and the second oil feeding device which circulates and returns to the oil tank of the second oil passage constitute a second lubrication system. This is the present invention. The j 4th feature. In addition, the aforementioned driving rotating member and driven rotating member correspond to the driving pulley 23 and the driven pulley 24 in the embodiment of the present invention described later, and the aforementioned oil mist forming device corresponds to the slingers 56 &, 56b. | According to this 14th feature, the crankshaft is lubricated by the first and second lubrication system | and the timing gear and cam of the valve-actuated device are lubricated by the second lubrication system, which can make the load larger The crankshaft is properly lubricated around. * The valve-actuating mechanism with a small square stop load is excessively lubricated, and the paper size of the oil mist can be adjusted to 财 0X29 ^ ---- -12-

------------------------ Installing ... (Please read the precautions on the back before filling this page). Order |: Line 丨

Description of the invention The circulation amount is controlled at the minimum production limit to reduce the amount of oil stored in the fuel tank, which can reach the fuel tank so that "the whole is small and lightweight." The invention is based on the 14th feature , Or the i-th oil delivery device can be placed in the second oil path with-& and closed when the crank chamber is depressurized, and the directional valve is opened when the pressure is increased, and the second oil delivery device is It is composed of the second directional valve which is closed when the crank chamber is depressurized in the third oil passage and opened when the pressure is increased. This is the fifth feature of the present invention. According to this fifteenth feature, Utilizing the pressure pulsation of the crank chamber and the one-way conveyors of the first and second directional valves can circulate the oil mist in the fuel tank, so 'no need to separately install a special oil fruit for this cycle, so that the structure can be made Simplification. The above and other purposes, features, and advantages in this month can clearly explain the appropriate embodiments detailed below according to the drawings. The following is a brief description of the drawings. The figures shown in Figure 1 to Figure 11 are the original The i-th embodiment of the invention; the one shown in FIG. I is a handheld type of the invention A perspective view of an example of the use of a stroke engine, FIG. 2 is a longitudinal sectional side view of the four-stroke engine, FIG. 3 is an enlarged view of a main part of FIG. 2, and FIG. 4 is an enlarged longitudinal view of a camshaft around FIG. Sectional view, Fig. 5 is a cross-sectional view taken along line 5-5 of Fig. 3, Fig. 6 is a system diagram of the engine's lubricating device, Fig. 7 is a cross-sectional view taken along line 7-7 of Fig. 3, and Fig. 8 is Section 8 of Figure 7 is a sectional view taken along line 8; Figure 9 is the bottom view of the cylinder head; Figure 丨 〇 a—The description of the suction effect of the oil stored in the cylinder head when the F series engine is in various operating positions. China National Standard (CNS) A4 specification (210X297 mm) ........ .....-... ---------------- Fate (Please read the notes on the back before filling this page) -13- 530114 A7 ____ B7 V. Description of the invention (11) The one shown in Figure 11 It is a cross-sectional view of a modified example of the oil delivery duct and the return oil passage corresponding to Fig. 7. The ones shown in Figs. 12 to 24 are the second embodiment of the present invention; and Fig. 12 is the hand-held four-stroke of the present invention. A longitudinal section of the engine. Figure 13 is a sectional view taken along line 13-13 of Figure 12. Fig. 14 is a cross-sectional view taken along line 14-14 of Fig. 12, Fig. 15 is an enlarged cross-sectional view of the main part of Fig. 12, Fig. 16 is an exploded view of a part of Fig. 15, and Fig. 17 is a view of Fig. 14 Section 17-17: Section 18, Section 18: Section 18-18: Section 14, Section 19: Section 19-19: Section 19, Section 20: Section 20-20: Arrow Directional view (that is, the bottom view of the cylinder head), FIG. 21 is a cross-sectional view taken along line 21-21 in FIG. 15, FIG. 22 is a lubricating road map of the engine, and the one shown in FIG. 23 corresponds to the one in FIG. 14. The engine is in an inverted state, and the one shown in FIG. 24 corresponds to the inverted state of the same engine in FIG. 14. 25 to 36 are the third embodiment of the present invention; FIG. 25 is a longitudinal sectional side view of the hand-held four-stroke engine of the present invention, and FIG. 26 is a cross-section taken along line 26-26 of FIG. 25 Fig. 27 is a sectional view taken along line 27-27 of Fig. 25, Fig. 28 is an enlarged sectional view of the main part of Fig. 25, Fig. 29 is a partial exploded view of Fig. 28, and Fig. 30 is a 27th part. Fig. 30-30 is a sectional view, Fig. 31 is a sectional view taken along the line 31-31 in Fig. 27, and Fig. 32 is a view taken along the arrow line 32-32 in Fig. 28 (namely, the bottom view of the cylinder head). The diagram is a sectional view taken on line 33-33 of Fig. 28. Fig. 34 is a lubricating roadmap of the engine. The one shown in Fig. 35 corresponds to the inverted state of the engine in Fig. 27. The one shown in Fig. 36 is Corresponding to the same engine in Fig. 27, it is lying down. First, starting from the first embodiment of the present invention shown in Fig. 1 to Fig. 11, the paper size applies the Chinese National Standard (CNS) A4 (210 X 297 mm) (please read the precautions on the back before writing) (This page) Order-Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs -14- 530114 Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs A7 _______ B7 V. Description of Invention (^) Explanation. As shown in FIG. 1, for example, when used as a power source of a power mower τ, the hand-held four-stroke engine is mounted on its driving portion. The dynamic grass trimmer T uses the cutter C in various directions depending on its working condition. Therefore, each time the engine E is tilted or turned upside down, its operating posture is not constant. Initially, the overall structure of the hand-held four-stroke engine e will be described with reference to Figs. 2 to 5.

> As shown in FIG. 2, FIG. 3 and FIG. 5, the hand-held four-stroke engine E is provided with a carburetor 2 and an exhaust muffler 3 respectively at the front and rear of the engine body 1, and is provided in the inlet of the carburetor 2. An air filter 4 is installed at the inlet. A fuel tank 5 made of synthetic resin is provided under the engine body 1. The engine body 1 is composed of a crank case 6 having a crank chamber 6a, a cylinder block 7 having a gas red hole 7a, and a cylinder head 8 having a combustion chamber 8a and inlet and exhaust valves 9, 10 opening in the chamber; The cylinder block 7 and the cylinder head 8 are integrally cast, and the crank case 6 is separately formed at the lower end of the cylinder block 7 and is bolted together. The crank case 6 is structured at the center to be divided into left and right first and second phase body halves 6L, 6R, and the two case halves 6L, 6R are joined to each other by bolts 12. On the outer periphery of the cylinder block 7 and the cylinder head 8, a plurality of fins 38 are formed. The crank shaft 13 accommodated in the crank chamber 6a is supported by ball bearings 14 and 14 so as to be able to rotate freely in the first and second case halves 6L and 6R. At the same time, it is connected and inserted into the connecting rod 16气 虹 孔 7a 的 铅 15。 The piston 15 in the rainbow hole 7a. In addition, the first and second case halves 6L, 6R are equipped with oil seals 17, ir, which are connected to the outside of the bearings 14, K and tightly outside the crank shaft 13. The paper dimensions are applicable to the Chinese country Standard (CNS) A4 specification (210 X 297 mm)

— — — — — — — — — — — 11 (Please read the notes on the back before filling out this page) 1 ^ 1. -15- 53〇li4 A7

No! Note 1

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First I read. Read

Back · Side I Order

------------ Μ — (Please read the notes on the back before filling this page) 1 «I- n ϋ; 线-

Printed by the Employees' Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 530114. A7 --- ___B7____ 5. Description of the invention (M) The arbor 13 can drive the camshaft% by a reduction ratio of i / 2. The aforementioned camshaft 26 and timing transmission 35 constitute the valve mechanism 53. In this way, the engine E is configured as a 0HC type (overhead camshaft type), and the timing transmission device 35 is configured as a dry type by being disposed outside the engine body. Between the engine body and the timing gear 35, a synthetic resin belt cover 36 fixed to the engine body 1 with bolts 37 is arranged to prevent the engine's radiant heat from affecting the timing gear 35. In addition, a fuel tank 40 made of synthetic resin is fixed to the engine body 1 with bolts 41. The tank 40 is configured to cover a part of the outside surface of the timing transmission 35, and the tank 40 is provided with a recoil starter. Device 42 (refer to Figure 2). Also in Figure 2, the other end of the crankshaft 13 on the opposite side of the timing transmission 35 also protrudes from the outside of the crank case 6, and a nut material is used on this end. A flywheel 43 is fixed. The flywheel 43 is integrally formed by a plurality of cooling blades 45 and 45 in an inner surface for mounting the cooling blades. A plurality of fixed hubs 46 (only one of which is shown in FIG. 2) are formed on the outer surface of the flywheel 43, and each of the fixed hubs 46 has a centrifugal block 47 supported to be freely rotatable. The centrifugal block 47 is a centrifugal clutch 49 (the original number is incorrect) together with the clutch drum 48 fixed on the drive shaft 50 described later. Once the number of rotations of the crank shaft 13 exceeds a predetermined value, the centrifugal block 47 is caused by The centrifugal force itself is crimped to the inner peripheral wall 'of the clutch drum 48 so that the output torque of the crank shaft 13 is transmitted to the drive shaft 50. The diameter of the flywheel 43 is larger than that of the centrifugal clutch 48. Covering the engine body 1 and the bow of the attached machine | Engine cover 51, the paper size of the timing transmission is applicable to the Chinese National Standard (CNS) A4 specification (210 x 297 mm) -17-530114 B7 V. Description of the invention (15) The part of the device 35 is divided into a first cover half 51a on the flywheel 43 side and a second cover half 51b on the starter 42 side, and is fixed to the engine body 1 respectively. A conical frustum-shaped bearing bracket 58 which is coaxial with the crank shaft 6 and is coaxial with the crank shaft 6 is fixed to the cover half 51a. The bearing bracket 58 is supported by a bearing 59 that drives the cutter c to rotate. The bracket 58 is also provided with an air suction port 52 for sucking outside air into the hood 51 as the cooling blades 45, 45 are rotated. A pedestal 54 covering the lower surface of the fuel tank 5 is fixed to the hood 51 and the bearing bracket 58. And the timing transmission device 35 for connecting the crankshaft 13 and the camshaft 26 is configured as a dry type, and is arranged on the outside of the engine body 1, there is no need to set a room on the side wall of the engine body 1 to accommodate the With the device 35, the engine body 1 can be thinned and miniaturized, and the entire engine E can be significantly lightened. And 'centering on the gas rainbow body 7 and connecting the timing transmission device 35 and the centrifugal block 47 of the centrifugal clutch 49 by the two ends of the crank shaft 13, the weight of the two ends of the crank shaft 13 is well balanced, and the engine E The center of gravity can be as close as possible to the central part of the crankshaft 13, so that it can complement the lightweight and improve the workability of the engine e. In addition, during the operation of the engine E, the load from the timing transmission 35 and the drive shaft 50 can be distributed to both ends of the crank shaft 13 to prevent the load from being concentrated on the crank shaft i 3 and supporting the crank shaft. The bearings 14, 14 can improve their durability. In addition, between the engine body 1 and the centrifugal block 47, a flywheel 43 having a diameter larger than that of the centrifugal block 47 and having cooling blades 45 is fixed on the crank shaft 13. Therefore, the size of the engine E caused by the flywheel 43 can be avoided as much as possible. It does not apply the Chinese National Standard (CNS) A4 specification (210 X 297 mm) at this paper size (please read the precautions on the back before «(write this page) • Install f! · Intellectual Property Bureau, Ministry of Economic Affairs, Consumer Consumption Cooperative Printing-18- 530114

Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs

The rotation of the cooling blade 45 hinders the centrifugal block 47, and external air can be sucked in from the air suction inlet 52 to be supplied to the cylinder block 7 and the cylinder head 8 in a timely manner, thereby improving the cooling performance. In addition, the fuel tank 40 in the engine body 1 is connected to the outside of the timing transmission device 35 late, and the fuel tank 40 covers at least a part of the timing transmission device 35 and covers the other part of the transmission device 35. The second cover half 5ib cooperates to protect the transmission 35. The fuel tank 40 and the flywheel 43 are arranged opposite to each other with the engine body 1 as the center, so that the center of gravity of the engine can be near the center of the crankshaft 13. Next, the lubrication system of the engine E will be described with reference to FIGS. 3 to 10. As shown in FIG. 3, one end portion of the crank shaft 13 is arranged so as to closely contact the oil seal devices 39 and 39 installed on the inner and outer side walls of the fuel tank 40, and penetrate the fuel tank 40 at the same time. The opening 55 between the inside of the fuel tank 40 and the crank chamber 6a is opened. The oil tank 40 stores lubricating oil 0, and its storage 1 is not determined so that the open end of the port 55 facing the oil tank 40 can be constantly exposed on the liquid surface of the oil 0 regardless of the engine E in any running posture. An oil-throwing ring 5 6 is fixed on the crank shaft 3 with a nut 57 inside the oil tank 40.忒 Sling ring 5 6 has two blades 56a, 56b which extend from the central part of the bulk in opposite directions to each other in the radial direction and bend in the axial direction toward the opposite side. The sling ring 56 is rotated by the operation of the crank shaft 13 ... no matter the engine e is in any running posture, at least one of the two blades 56a, 56b will spread the oil 0 within the fuel tank 40 to form an oil mist. In FIGS. 3, 6 and 7, the crank chamber 6a is connected to the valve cam chamber 21 through an oil delivery duct 60, and the oil delivery duct 60 is provided with a valve that can be used only from the crank chamber to the paper size. Home Standard (CNS) A4 Specification (210 X 297 Public Love)

-19- V. Description of the Invention (Π) 6a A non-return valve 6ι flowing in the direction of the valve-moving cam chamber 21 side. The oil delivery pipe 60 is formed as a body along the -side edge of the aforementioned belt cover 36, and a valve chamber 62 is formed at the lower end of the oil delivery pipe 60. The belt cover is formed with an inlet ⑽ protruding from the middle of the belt cover 36 from the middle, and the inlet pipe 63 is fitted into a connection hole 64 in the lower portion of the crank case 6 through an oil seal member 65 to communicate with the crank chamber 6a. The valve chamber 62 is provided with the aforementioned one-way valve 61 which can only flow from the inlet pipe 0 in the direction of the valve chamber 62, and the one-way valve "is constituted by a reed valve in the example shown in the figure. Also, a belt The cover 36 is integrally formed with an outlet pipe 66 protruding from the upper end of the oil delivery duct 60 from the inner side of the belt cover 36, and the outlet pipe 66 is fitted into a connection hole 67 on the side of the cylinder head 8 to communicate with the valve cam chamber 21. In this way, the valve-actuated cam chamber 2 i communicating with the oil delivery duct 60 communicates with the ventilation in the side wall cap 30 through a gas-liquid separation passage 68 provided on the cam shaft 26 and composed of a horizontal hole 68 a and a vertical hole 68 b. The air chamber 69 is in communication with the air pipe 70 in the air cleaner 4. The figures 4 and 9 clearly show that the cylinder head 8 is used to lock the valve cam chamber 21 and the upper surface is opened. The cylinder head 71 is joined by an oil seal member 72. The cylinder head 71 is formed with a suction chamber 74 that communicates with the valve cam chamber 21 through a plurality of orifices 73, 73. The suction chamber 74 is It is flat along the upper surface of the valve-moving cam chamber 21, and its four corners of the bottom wall are provided with four holes 73 and 73. Two long and short siphons 75 and 76 are integrally formed on the bottom wall. The siphons 75 and 76 are integrally arranged at the center and spaced in a direction orthogonal to the axis of the camshaft 26 and protrude from the valve-actuated cam chamber 21, and are provided with orifices. 73, 73. As shown in Figures 6 to 8, the suction chamber 74 can apply the Chinese National Standard (CNS) A4 specification (210 X 297 public love) through the paper size in the other direction. -20- 530114

The guide & 78 communicates with the fuel tank 40, and the oil return pipe 78 is integrally formed along the other side edge of the belt cover 36 on the opposite side of the oil feed pipe 60. The belt cover 36 is integrally formed with an inlet officer 80 protruding from the upper end of the oil return duct 78 and protruding from the side of the belt cover 36. The inlet pipe 80 is connected to the outlet pipe 82 of the cylinder head 71 through a connector Η for communication. Suction chamber 74. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs

(Please read the precautions on the back before filling in this page.) Also, the belt cover 36 is integrally formed with an outlet pipe 82 protruding from the lower end of the oil return duct 78 to the inside of the belt cover 36. The outlet pipe 82 is fitted in the An oil return hole 83 on the fuel tank 40 communicates with the fuel tank buckle. The opening of the oil return hole 83 is arranged near the central portion in the fuel tank 40 so that it can be exposed on the liquid surface of the oil in the fuel tank 40 regardless of the running posture of the engine. In addition, a crank shaft is protruded from the front end of the outer side of the fuel tank 40, and a driven member 84 is fixed by the aforementioned recoil starter 42. However, during the operation of the engine E, due to the rotation of the crankshaft 13, the oil slinger 56 in the oil tank 40 stirs the lubricating oil 〇 and disperses to form an oil mist, and the crank chamber 6 a is reduced due to the upward movement of the piston 15. When pressed, the oil mist is sucked into the crank chamber 6a 'through the opening 55 to lubricate the crankshaft 丨 3 around the piston 丨 5. Next, when the crank chamber 6 & is boosted due to the downward movement of the piston 15, by opening the check valve 61, the aforementioned oil mist is sucked into the oil supply duct 60 together with the blow-by gas mixture generated by the crank chamber 6a and supplied. In the valve-actuated cam chamber 21, the camshaft 26 or the cam followers 24, 25 and the like are lubricated. Once the oil mist and channeling gas mixture in the valve-driven cam chamber 21 enters the gas-liquid separation path 68 of the rotating camshaft 26, the gas-liquid is centrifuged in this path 68. Then the liquefied oil is separated by gas-liquid The horizontal hole 68a of the passage 68 returns to the wide-moving cam chamber 21, and the air-cylinder mixing gas is adapted to the Chinese National Standard (CNS) A4 specification (21〇X 297 gt) according to the paper size during the intake stroke of the engine e. -21- 530114 A7 B7 V. Description of the invention (I9 sequence is sucked into the engine E through the ventilation chamber 69, the ventilation pipe 70 and the air filter 4. However, as described above, the valve-actuated cam chamber 21 is provided by The air-liquid separation passage 68, the vent chamber 69, and the vent pipe 70 are connected to the air filter $. Therefore, the pressure of the valve-actuated cam chamber 21 is maintained by atmospheric pressure or some of its low pressures. Only the positive pressure component of the pressure pulsation is discharged to the valve 61, so that the crank chamber 6a assumes an average negative pressure state, and the negative pressure is transmitted to the oil tank 40 through the port 55, and then to the suction through the oil return pipe 78 Chamber 74, so the pressure of the suction chamber 74 is lower than that of the valve cam chamber 21, and The force is lower than the suction chamber 74. As a result, the pressure is generated from the valve-driven cam chamber 21 through the siphons 75, 76 and the orifices 73, 73, ... to the suction chamber 74, and then through the oil return pipe 78 to the fuel tank. 40 movement, so the oil mist in the valved cam chamber 21, or the oil accumulated in the valved cam chamber 21, is sucked into the suction chamber 74 through the siphons 75 and 76 and the orifices 73 and 73. It then flows down to the oil return duct 78 and returns to the oil tank 40. At this time, four holes 73, 73 ··· are formed at the four corners of the bottom wall of the suction chamber 74 as described above, and are located in the center of the bottom wall. The two siphons 75 and 76, which protrude from the valve-actuated cam chamber 21 and are spaced in a direction orthogonal to the axis of the camshaft 26, are also provided with orifices 73 and 73. Therefore, as shown in FIG. 10, the engine £ It goes without saying in the upright state (A), even in the left-leaning state (b), the right-leaning state (C), the left-side turning state (D), the right-side turning state (e), or the upside-down state (F). Regardless of the running posture, the oil accumulated in the valve-actuated cam chamber 21 should be more than any one of the orifices 73 and 73 in the six. Use the Chinese National Standard (CNS) A4 specification (210 X 297 mm) (Please read the notes on the back before writing this page) Order, --line * Printed invention description printed by the Consumers ’Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs (2 〇) The oil can be sucked into the suction chamber 74. In this way, the OHC four-stroke engine e can use the pressure pulsation of the crank chamber 及 and the function of the check valve 61 to supply the atomized oil in the fuel tank 40. Move the crank to 6a and widen the cam chamber 21 and return it to the fuel tank 40. Therefore, the non-reduced engine E assumes any running posture, and the interior of the engine can be lubricated with oil mist, and there is no need to install another to make the oil The special oil pump for the mist circulation can achieve the effect of simple structure. Also, not only the fuel tank 40 made of synthetic resin, the oil delivery duct 60 connecting the crank chamber 6a and the valve cam chamber 21, and the oil return guide 78 connecting the suction chamber 74 and the fuel tank are all arranged in the engine body. In addition, it does not hinder the thinning and miniaturization of the engine body j, and helps the engine E to achieve a significant weight reduction effect. In particular, the external oil supply duct 60 and the oil return duct 78 are not easily affected by the heat from the engine E, so that the lubrication oil can be prevented from overheating. In addition, because the oil delivery duct 60, the oil return duct 78, and the belt cover% are integrated, it is beneficial to reduce the number of parts and improve assembly. What is not shown in FIG. 11 is a modified example of the oil delivery duct 60 and the oil return duct 78. At this time, the oil delivery duct 60 and the oil return duct 78 are detached from the belt cover 36 and made of rubber or the like Made up. The rest of the structure is the same as that of the previous embodiment, so the parts corresponding to the previous embodiment in the figure are given the same reference numerals, and descriptions thereof are omitted. According to the modified example, no matter where the positions of the oil delivery duct 60 and the oil return duct 78 are connected to each other, they can be freely arranged by appropriately bending these ducts and π, thereby expanding the freedom of arrangement. Also, the one-way valve 61 provided in the aforementioned first embodiment may also be a rotary read 530114 A7

V. The description of the invention (21) is replaced, and the rotary valve is linked with the crank shaft 3, and can be actuated to make the oil delivery pipe 60 conduct when the piston 15 descends, and cut off when it rises. Next, a second embodiment of the present invention will be described with reference to Figs. 12 to 24. Figs. In Figs. 12 and 13, on the engine body 101 of the hand-held four-stroke engine e, a carburetor 102 and an exhaust muffler 103 are respectively arranged at the front and rear, and the carburetor 102 is located at the inlet of the air inlet and Equipped with an air filter 104. A fuel tank made of synthetic resin is further installed under the engine body 101. The crank shaft 113 protrudes from both ends of the engine body 101 and the two outer sides of the fuel tank 140 adjacent to the engine body 101 side, and a recoil starter 142 is provided on the outer side of the fuel tank ι40. It is a driven member 184 which can be driven and connected to one end thereof. The other end of the crank shaft 113 is fixed with a cooling fan 143 with a flywheel attached. A plurality of fixed hubs 146 are formed on the outer side of the cooling fan 143 (only one of them is shown in FIG. 12), and each of the fixed hubs 46 supports a freely rotatable centrifugal block 147. The centrifugal block 147 forms a centrifugal clutch 149 together with a clutch drum 148 fixed to the drive shaft 150 described later, and once it exceeds a specific value of the number of rotations of the crank shaft 113, the centrifugal block 147 is due to its own centrifugal force. The inner peripheral wall of the clutch drum 148 is crimped, and the output torque of the crank shaft 113 is transmitted to the drive shaft 150. The diameter of the cooling fan 143 is larger than that of the centrifugal clutch 149. The engine cover 151 covering the auxiliary equipment other than the engine body 101 and the fuel tank 105 is fixed at an appropriate position of the engine body 101, and a cooling air intake is provided between the engine cover 151 and the fuel tank 105. 119. Therefore, this paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297 mm) iL ---.------- ^ installation! (Please read the notes on the back first to write this page) 'Order. • Line. Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economics -24- 530114 Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economics A7 B7 5. Description of the invention (r ) By the rotation of the cooling fan 143, the outside air is sucked in by the cooling air suction port 119 for cooling of each part of the engine E. The hood 151 is fixed with a circular 'frustum-shaped bearing bracket 1 58 which is coaxial with the crank shaft 113. The bearing bracket 1 58 supports the drive shaft through a bearing 159 as in the first embodiment. 150, the cutter C of the lawnmower τ (see Fig. 1) is driven by rotation. And 'Place the engine body 101 in the middle, and arrange the fuel tank 140 and the starting device 142 on one side, and the cooling fan 143 and the centrifugal clutch 149 on the other side, respectively, the right and left weight of the engine E is well balanced, and the engine e The center of gravity can be as close to the center of the engine body 101 as possible, thereby promoting the maneuverability of the engine E. In addition, a cooling fan 143 having a diameter larger than that of the centrifugal block 147 is fixed on the crank shaft U3 between the engine body 101 and the centrifugal block 147, so that the enlargement of the engine E due to the cooling fan 143 can be avoided as much as possible. Next, the structure of the engine body 101 and the fuel tank 140 will be described with reference to FIGS. 12 to 15, 16, 20, and 21. In Figures 12 to 15, the engine body 101 is composed of a crank case 106 having a crank chamber 10 to-, a cylinder block 107 having a cylinder hole 107 &, and a combustion chamber 108a and The chamber i08a is formed by a cylinder head 108, which has an inlet opening and an exhaust port 1109 and 110, and a large number of fins 138 are formed on the outer periphery of the cylinder block 07 and the cylinder head i08. The crank shaft 113 housed in the crank chamber 106a is supported on the left and right side walls of the crank case i 06 by ball bearings 114 and 114, and can be rotated freely. At this time, the ball bearing on the left side 14 has an oil seal, and the paper size on the right side is in accordance with China National Standard (CNS) A4 (210 X 297 public love) ^ -------- ^ ----- ---- ^ (Please read the notes on the back before filling this page) -25- 530114

5. Description of the invention (23) The ball bearing 114 is an oil seal device adjacent to the outer side. The crank shaft 113 is connected to a piston 115 embedded in the cylinder hole 107a through a car cup 116 as a conventional device. The left side wall of the crank case 106 is integrally connected with the oil tank 14 adjacent to the outer side, and the oil tank 140 is arranged through the crank shaft 13 and its end with oil-sealed ball bearings 14 on the side. Moreover, an oil seal device 139 is installed on the outer side wall of the oil tank 14 penetrated by the crank shaft 113. A belt guide cylinder 186 is integrally connected to the top wall of the fuel tank 140, and runs through a flat cross-section that extends up and down the top wall and is open at both ends. The lower end of the belt guide cylinder 186 extends to the vicinity of the crank shaft 13 in the fuel tank 140, and the upper portion thereof is connected to the cylinder head 10 8 to have a partition wall 1 § 5 connected to form a unit. A series of annular oil seal protrusions 1 87 'are formed on the upper edges of the cylinder head 108 and the belt guide cylinder 186, and the partition wall 185 projects above the oil seal protrusion 187. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs In addition, as shown in Figures 16, 20, and 21, a circular oil seal groove 188a corresponding to the aforementioned oil seal protrusion 1 8 7 is formed on the lower end face of the cylinder head 丨 36, respectively. A linear oil seal groove 188b is formed on the inner surface of the cover 136 to communicate between the two sides of the annular oil seal groove 188a. The annular oil seal groove 188a is provided with an annular seal packing 189a, and the linear oil seal groove is formed in the linear oil seal groove 188a. 188b is provided with a linear seal packing 189b formed integrally with the annular seal packing 189a. In addition, the cylinder head 136 is coupled to the cylinder head 108 with bolts 137 to crimp the annular seal packing 189a and the oil seal protrusion 187, respectively, and the linear seal packing 189b to the partition wall 185. In addition, it is divided into the first valve operating chamber 121a divided by the belt guide cylinder 186 and one half of the cylinder head 136, and the cylinder head 108 and the cylinder head 136. The paper size applies to Chinese National Standard (CNS) A4 Specifications (210 X 297 mm) -26-

Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs

530114 V. The second valve action chamber 121b delineated by the other half of the invention description (24), and the two valve action chambers i21a, 121b are separated by the aforementioned partition wall 185. In FIGS. 12 to 15, the engine body 101 and the fuel tank 14 are divided into an upper block Ba and a lower region on a plane passing through the axis of the crank shaft 113 and perpendicular to the axis of the cylinder bore 107a. Block Bb. That is, the upper block is composed of the upper half of the crankcase 106, the cylinder block 107, the cylinder head 108, the upper half of the fuel tank 40 and the belt guide tube 186, and the lower block Bb The lower half of the crank case 106 and the lower half of the fuel tank 140 are integrally connected. The upper and lower blocks Ba and Bb are individually cast, and after each part is processed, a plurality of bolts 112 are used (see FIG. 14). Combine each other. The intake valve 118i and the exhaust valve 118e on the cylinder head 108, which are used to open and close the intake port 109 and the exhaust port 110 respectively, are arranged parallel to the axis of the cylinder hole i07a, and the spark plug 120 Its electrode is close to the combustion chamber 108 and is screwed to it. Next, the valve operating mechanism 122 for opening and closing the intake valve 118i and the exhaust valve 118e will be described with reference to Figs. 13 to 17. The valve actuating mechanism 122 is a winding timing transmission device 122a disposed across the first valve actuating chamber 121a from the fuel tank 140, and a second valve actuating chamber 12 is passed from the first valve actuating chamber 121a. The cam device 122b is configured by lb. The winding timing transmission 122a is driven by a driving pulley 123 fixed on a crank shaft 113 in the fuel tank 140, a driven pulley 124 supported on the upper part of the belt guide cylinder 86 to be freely rotatable, and a The timing transmission belt 125 is wound between the driving and driven pulleys 123 and 124, and the driven pulley 124 is integrated with the cam 126 forming a part of the cam device 122b on the end surface on the side of the partition wall 185. . Driven and driven pulleys This paper is sized for China National Standard (CNS) A4 (210 X 297 mm) -27- ^ -------- ^ --------- ^ (please first Read the notes on the back and fill in this page) 530114 A7 B7 Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 1. Description of the invention (25) 123, 124 are toothed, and drive the pulley 123 and pass the belt 125 to 2 The reduction ratio of 1/1 drives the driven pulley 124. A support wall 127 is formed integrally on the outer side wall of the belt guide cylinder 186 and stands on the inner side of the annular oil seal protrusion 187 to contact or approach the cylinder head 136. The support wall 127 and the aforementioned partition wall 185 are separately provided. There are through-holes 128a and bottomed holes 128b which are higher than the oil seal protrusion 187 and are coaxially arranged. Moreover, both ends of the support shaft 129 are supported by the through holes 128a and the bottomed holes 128b so as to be rotatable freely, and the aforementioned driven pulley 124 and cam 126 are supported by the middle portion of the support shaft 129 to be freely rotatable. status. Before the cylinder head 136 is installed, the supporting shaft 129 is inserted into the bottom hole 128b through the through hole 128a through the shaft hole 135 ′ of the driven pulley 124 and the cam 126. After the insertion, the cylinder head 136 is aligned with the cylinder head 108 and the belt guide cylinder 186. If the inner surface of the cylinder head 136 faces the outer end of the support shaft 129, the effect of preventing the shaft 129 from coming out of the through hole 128 & is achieved, and the bottom of the bottomed hole 128b is used as the shaft 129 facing inward. The floor of the move. In this way, the support shaft 129 is restricted from moving in the inner and outer axial directions. Therefore, there is no need to install a special brake member for the supporting shaft 129, and the supporting shaft 29 is lubricated in the cylinder head 136, and the oil tight joint of the cylinder head 136 and the cylinder head 108 can prevent the If the oil leaks out, there is no need to further provide an oil seal member on the support shaft 129, which can reduce the number of parts and promote cost reduction. In addition, the support wall 127 standing inside the oil seal protrusion 187 has a through hole 12 ″ higher than the oil seal protrusion 187, and a cylinder head 136 is formed on the outer side of the support wall 127 to contact or approach the The inner surface of the cylinder head 136, so that one side can be loaded and unloaded before the cylinder head 136 is installed, and one side can achieve the effect of miniaturization of the cylinder head 136. This paper size _ X 297 mm) (Please read the precautions on the back first again'

Line--28- 530114 A7 B7 V. Description of the invention (26) A pair of bearing sleeves 130 丨, 13 (^, which are parallel to the support shaft 129 and protrude from the second valve operating chamber 1211) side are integrally formed on the partition wall 185. The cam device 12213 is fixed by the aforementioned cam 126 and the intake rocker shaft 131i and exhaust rocker shaft i31e and the first valve operating chamber 121a, which respectively support the bearing sleeves 13i and 13Oe to be rotatable. The intake cam followers 132i and the exhaust cam followers 132e and the second wide moving chamber 121b are fixed to the intake air respectively at the ends of the rocker shafts 131i and 131e and the front end is slidably connected below the cam 126. And one end of the exhaust rocker arm shafts 131i and 131e, and the front end portion directly contacts the intake valve. The intake rocker arm 133i and the exhaust rocker arm 133e at the upper end of the 18i and the exhaust valve 118e are respectively installed on the intake valve. The 118i and the exhaust valve 118e are constituted by an intake spring 134i and an exhaust spring 134e which give them potential energy in the direction of opening and closing. The drive pulley 123 which rotates at the same time as the crank shaft 113 rotates is the belt 125. Rotate the driven pulley 124 and the cam 126, and the cam 126 shakes the intake and exhaust cam followers 132i and 132e in a timely manner. The corresponding rocking motions are transmitted to the intake and exhaust rocking arms 133i and 133e through the corresponding rocker arm shafts 131i and 13le, and the rocking is performed by the rocking arms. Coordination of 134i and 134e is printed by opening and closing the intake and exhaust valves 118i and 118e in a timely manner. It is printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs (please read the precautions on the back before filling this page). The driven pulley 124 and the cam 126 are supported on the supporting shaft 129 so as to be able to rotate freely, and the supporting shaft 129 is also supported on both side walls of the first wide moving chamber 121 a in a freely rotatable state, then the driven pulley 124 When the cam 126 is rotating, the supporting shaft 129 also rotates due to frictional drag, thereby reducing the rotation speed difference between the driven pulley 124 and the cam 126 and the supporting shaft 129. Therefore, the effect of reducing the wear of the rotating sliding portion can be achieved. Therefore, even if This paper size applies to China National Standard (CNS) A4 (210 X 297 mm) -29- 530114 A7 B7 V. Description of the invention (27) No special material or surface treatment is used, which will still help to improve the cam 126 and support The durability of the shaft 12 9. The larger-diameter cam 126 is arranged on one side of the cylinder head 108 together with the driven pulley 124, and only the intake and exhaust rocker arms 133i, 133e and the smaller-diameter inlet are arranged directly above the cylinder head 108. The air and exhaust rocker arm shafts 131m, 13le, the valve actuation mechanism 122 will not increase the volume significantly above the cylinder head 108, and reduce the overall height of the engine E, which can further contribute to the miniaturization of the engine e. In addition, the support shaft 129 and the intake and exhaust rocker shafts 131i and 131e are arranged at a position higher than a series of annular oil seal protrusions 187 at the upper end of the cylinder head 108 and the upper end of the belt guide cylinder 186. In the disassembled state, the oil seal protrusion 187 will not cause any obstruction, and the support shaft 12 9 and the air intake and exhaust rocker arm shafts 131i and 131e can be assembled and disassembled above it, and the assembly and maintenance are both Extremely good. Next, the lubrication system of the engine E will be described with reference to Figs. 13 to 22. Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs. As shown in Figures 14 and 15, the oil tank 140 stores the self-supply port 140a and fills it with the required amount of lubrication oil. A pair of slinger rings 156a, 156b are fixed on the crank shaft 113 in the fuel tank 140 by press-fitting or the like to hold the driving pulley 123 and juxtaposed in the axial direction. The slinger rings 156a and 156b extend in completely opposite radii to each other, and at the same time the front end is bent in the direction of the axis facing away from each other. Once driven by the crank shaft 113, the two slinger rings 156a At least one of 156b stirs the oil stored in the oil tank 140 and scatters it to form an oil mist. At this time, the generated oil flystroke is sprayed on a part of the timing transmission device 122a exposed from the first valve actuation chamber 121a inside the fuel tank 140, and enters the first valve actuation chamber 121a to directly lubricate the -30- Paper size applies to China National Standard (CNS) A4 (210 X 297 mm) 530114 A7 V.

Description of the invention (28) A timing transmission device 122a, which is one of the lubrication systems. Another lubricating system, as shown in FIGS. 13 to 15 and 22, includes: a port 155 provided on the crank shaft to communicate between the interior of the fuel tank 140 and the lower portion of the crank chamber 106a; The outer side of the main body ι〇1, so that the lower part of the crank chamber 106a is connected to the oil delivery duct 160 at the lower part of the second valve action chamber 12lb;-It is arranged on the cylinder head 108 to attract the liquefied and accumulated oil in the second valve action chamber mb An oil recovery chamber 174;-formed between the cylinder head 08 and the oil tank 140 so that the oil recovery chamber 174 communicates with the return oil passage 178 of the oil tank 140 through the first valve actuating chamber 12la; and a crank chamber 〇6a The lower part of the one-way valve 16 that allows the oil mist to flow from the crank chamber 106a in the direction of the oil delivery duct 160. The aforementioned port 155 is arranged at the open end 155a facing the oil tank 140 in the oil tank 140. The central part or its vicinity, so that it can always be exposed on the liquid surface of oil 0 in the fuel tank M0 regardless of the posture of the engine e. The open end 155a is placed between the drive pulley 123 fixed on the crank shaft 113 and one of the slinger 156a so that the open end i55a is not blocked. The one-way valve 161 (refer to FIG. 13) is constituted by a reed valve in the example shown in the figure, and is used in the crank chamber in conjunction with the reciprocating movement of the piston 115! 〇6a Close valve when negative pressure state 'Open valve when positive pressure state. A splicing pipe 162a (refer to FIG. 13) protruding from the lower part of the outer side of the crank case 106 is inserted and connected below the end of the oil delivery pipe 1 60, and a protruding projecting from the cylinder head 108 is inserted into the upper part. The upper part of the side continues the officer 162b (see FIGS. 14 and 18). On the one hand, the inside of the upper connection pipe 162b is connected by a large passage area formed on the cylinder head 108 --------- I--1-installed! I I II I Order ------- I (Please read the notes on the back before filling out this page) Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs

530114

V. Description of the invention (29) The printed road 163 (refer to Figures 18 and 19) of the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs communicates with the lower part of the second valve operating chamber 1211). The bypass pipe 164 communicates with the return oil passage 78. As shown in FIGS. 15, 20, and 21, a partition 165 of a vent chamber 169 is drawn on the top wall of the cylinder head 136 on the upper part of the cylinder head 136 so as to protrude from the top wall. A plurality of pillars 166 are installed with the clamping clips 167 to lock them, and the venting chamber 169 is connected with a partition plate 165 integrally and protrudes from the second valve actuating chamber on the 12 lb side. 168, and the gap g between the partition plate 165 and the inner surface of the cylinder head 136 communicates with the second valve operating chamber 121b, and on the other hand, it communicates with the air cleaner ι04 through a vent pipe 170. The venting chamber 169 is used for gas-liquid separation of the oil in a mixed state and the blow-by gas from the cylinder, and a baffle 172 for promoting the gas-liquid separation is protruded from the inner surface of the top wall of the cylinder head 136. The partition plate 165 is welded with a box-shaped spacer 179 which defines the aforementioned oil recovery chamber 174 'between the upper surface and the surface thereof and has a τ-shape when viewed from the plane and an open surface. Therefore, the oil-recovery chamber 174 also has a τ-shape. Two siphons 175 are integrally provided on the partition plate 165, and are used to communicate with the two ends of the T-shaped horizontal rod of the oil recovery chamber 174, respectively. The front ends of the siphons 175 extend to the vicinity of the bottom surface of the second valve operating chamber 12 lb, and the front ends of each of the siphons 175 form openings 175a. On the upper wall of the spacer 179, three siphon pipes 176 are integrally protruded, and are used to respectively connect three front ends of the T-shaped horizontal rod and the vertical rod of the oil recovery chamber 174. The front ends of the siphons 176 extend to the vicinity of the top surface of the ventilation chamber 169, and the front ends of each of the siphons 176 are opened to form apertures 176a. In addition, a spacer is provided on the upper wall of the spacer 179 to make the upper part of the spacer fit the Chinese paper standard (CNS) A4 (210 X 297 mm). -32- (Please read the precautions on the back first ^ Write this page again) Binding • Binding • 530114 A7 ----——-___ B7____ V. Description of the invention (3〇) 165a communicates with the orifice 180 of the oil recovery chamber 174. In addition, a partition 165 is integrally provided with a guide tube 181 for communicating with oil recovery, and the front end of the T-shaped longitudinal rod of the chamber 174. The front end of the guide tube 181 is fitted with a grommet 182. In the month opening on the bottom surface of the second valve operating chamber 121b, the inlet 178a of the return oil passage 178 is described. In this way, the oil recovery chamber 174 is connected to the return oil passage 178. The above-mentioned conduit 1 8 1 is disposed near an inner side surface of the second valve operating chamber 121b, and the portion near the inner side is provided with an oil suction opening 181a for communicating the second wide operating chamber 12 lb. Into the catheter 181. The 'ventilation chamber 169 is connected to the air cleaner 104 through the vent pipe 170. Therefore, even when the engine E is running, the pressure in the ventilating chamber 169 is maintained at approximately atmospheric pressure, and through the ventilating chamber In 169, the resistance of the oil circuit is small. The second valve moving chamber 121b connected by the communication pipe 168 is about the same pressure as the ventilation chamber 169.

The crankshaft chamber 106a printed by the employee's consumer cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs generates pressure pulsation by lifting and lowering the piston 115 during the operation of the engine E, and only discharges the positive pressure component from the check valve 161 to the oil delivery duct 160. Therefore, the crank chamber 1 06a shows an average negative pressure state, and the second valve actuating chamber 12lb that bears the positive pressure is connected to the venting chamber 169 through a communication pipe 168 with a small oil path resistance, so it is approximately the same as the venting chamber 169 pressure. The negative pressure in the crank chamber 106a is transmitted to the oil tank 140 through the opening 155 of the crank shaft 113, and is further transmitted to the oil recovery chamber 174 through the return oil passage 178. Therefore, the pressure of the oil recovery chamber 174 is higher than that of the second valve The chamber 12 lb or the venting chamber 169 is lower, and the pressure of the oil tank 140 and the first valve actuating chamber 12la is lower than that of the oil recovery chamber 174. Therefore, as shown in Figure 22, if the pressure of the crank chamber 106a is pc, -33- installed -------- order (please read the precautions on the back before filling this page) The dimensions are applicable to the Chinese National Standard (CNS) A4 specification (210 X 297 mm) 530114 B7___ 15. Explanation of the invention (M) The pressure of the oil tank 140 is ρ〇, and the pressure of the first valve operating chamber 12la is Pva. The pressure of the 2-valve operating chamber 121b is pvb, the pressure of the oil recovery chamber 174 is Ps, and the pressure of the venting chamber 169 is Pb. The relationship between the magnitudes can be expressed by the following formula.

Pvb = Pb > Ps > P〇 = pva > Pc According to this result, the pressure of the second valve moving chamber 12lb and the venting chamber 169 is passed through the siphon 175, 176 or the orifice 180 to the oil recovery chamber 174, and then through the return oil path 178 to the fuel tank 140, and moved to the crank chamber 106a. During the operation of the engine E, the throwing rings 1 56a and 156b in the oil tank 140 which rotate with the crank shaft 113 stir the lubricating oil and cause it to fly away, thereby forming an oil mist. The oil droplets generated at this time are sprayed on a part of the timing transmission device 122 & exposed from the belt guide cylinder 1 86 to the fuel tank 140, that is, a part of the driving pulley 23 and the timing transmission belt 25, or entering the first section as described above. 1 valve actuating chamber 121a, and directly lubricate the timing transmission 122a. Even if the oil droplets are sprayed on only a part of the timing transmission device 122a, the oil will not only lubricate the entire device 122a with the operation of the timing transmission device 122, but will also be transmitted to the cam 126, which can also effectively lubricate . The oil mist formed in the oil tank 140 is sent along with the aforementioned pressure flow, is sucked into the crank chamber 106a through the opening 155 of the crank shaft 113, and lubricates the crank chamber 106a and the periphery of the piston 115. Then, when the crank chamber 10 & is under positive pressure due to the drop of the piston 115, by opening the check valve 161, the oil mist and the blow-by gas mixture generated by the crank chamber 106a rise to the oil delivery duct together. 160 and the communication path 163 are supplied to the second valve operating chamber 121b and lubricate each part of the cam device 122b in the chamber 12lb, that is, the intake and exhaust rocker arms 133i and 133e. This paper size applies to the Zhongguanjia Standard (CNS) A4 size coffee x 297 public hair) ----- (Please read the precautions on the back before '

Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 530114 V. Description of the invention (32) At this time, the part of the oil mist passing through the communication path 163 is short-circuited by the hole-shaped bypass pipe 164 and connected to the return oil path 178. Therefore, by appropriately setting the oil path p and the force of the bypass pipe 164, the supply amount of the oil mist to the second moving chamber 121b can be adjusted. If the oil mist and channeling gas mixture in the second wide moving chamber 121b moves to the ventilation chamber 169 through the gap g around the communication pipe 168 and the partition plate 165, at this time, due to the expansion effect and the conflict with the baffle 172 When the gas-liquid separation is performed, and the blow-by gas mixture is in the intake stroke of the engine E, it will be sucked into the engine E through the air pipe 170 and the air filter 104 in order. When the liquefied oil in the vent chamber 169 is in the upright state of the engine E, the depression 165a or the communication pipe 168 or the gap g accumulated on the spacer 179 flows down and is accumulated on the bottom surface of the second valve actuation chamber 12lb. The orifices 180 or siphons 175 waiting in these places suck them into the oil recovery chamber 174. When the engine E is in an inverted state, the liquefied oil will accumulate on the top surface of the cylinder head 13 6 and sucked into the oil recovery chamber 174 through the siphon pipe 176 waiting there. • In this way, the oil sucked into the oil recovery chamber 1 74 was returned to the oil tank 140 from the duct 1 8 1 through the printed circuit 1 78 of the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs. At this time, as shown in the example shown in the figure, the return oil passage ~ 178 communicates with the oil tank 140 through the second valve operating chamber 121b, and the oil from the return oil passage-178 is sprayed on the timing transmission device 122a, which is helpful The condition of its lubrication is good. Further, the aforementioned venting chamber 169 is partitioned between the top surface of the cylinder head 136 and the partition plate 165 installed on the inner wall of the cylinder head 136, and the aforementioned oil recovery chamber 174 is partitioned between the partition plate 165 and the spacer 179 welded thereon. Therefore, it is not necessary to divide the top wall of the gas red cover 136 to install an oil recovery chamber 174 and Tong-35 on the cylinder head 136. This paper size applies to the Chinese National Standard (CNS) A4 specification (210 X 297 mm) 530114 A7 _ B7 V. Description of the invention (33) Air chamber 169. And 'these venting chambers 169 and the oil recovery chamber 174 exist together in the cylinder head 136, so no matter how much oil leaks from the two chambers 169, 1 74, the oil flows back to the second wide moving chamber 121b' without generating any Obstacle, without the need for oil-tight inspection around the two rooms 169, 174, so as to achieve the effect of reducing production costs. In addition, the spacer 179 can be fused to the partition plate 165 before the partition plate 165 is mounted on the cylinder head 136, so the formation of the oil recovery chamber 174 can be simplified. Since the siphons 175 and 176 are integrally formed on the partition plate 165 and the spacer 179, respectively, the formation of the siphons 175 and 176 can be simplified. In addition, when the engine E shown in FIG. 23 is in an inverted state, the oil 0 stored in the fuel tank 140 will move to the top side of the fuel tank 140, that is, the side of the first valve operating chamber 12la, and be guided by the belt 186 The opening end of the first valve actuating chamber 121 & toward the oil tank 140 is set to a position higher than the liquid level of the storage oil 0, so that the stored oil 0 is not allowed to flow into the second valve actuating chamber 12 1 b. At the same time, the oil supply of the timing transmission device 122a is excessive, and at the same time, the amount of oil in the oil transfer tank 14 can be maintained at a specific amount, so that oil mist can continue to be formed by the oil slinger rings 156a, 156b. As shown in FIG. 24, if the engine E is in a horizontal state during operation, the stored oil 0 will move to the side of the fuel tank 140, and the first valve operating chamber 12la will be directed toward the fuel tank 140 by the belt guide cylinder 186 The open end is set at a position higher than the liquid level of the stored oil. Therefore, at this time, the stored oil will not be allowed to flow into the second valve operating chamber 121b, which can prevent excessive oiling of the timing transmission device 122a. At the same time, it can be ensured that the amount of oil in the fuel tank 140 is maintained at a specific amount, so that oil mist can continue to be formed by the oil slinger rings 156a, 156b. In addition, when the engine E is turned down as described above, the timing paper size of the timing transmission device 122 & applies to the Chinese National Standard (CNS) A4 specification (210 X 297 public love) (Please read the precautions on the back before writing the copy (Page) · • Line · Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs -36- Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 530114 A7 -_____ B7_____ V. Description of the invention (34) The upper part 125a of the transmission belt 125 is from the drive side Moving to the driven side, a pair of oil drop induction walls 190 (refer to FIGS. 15 and 24) are integrally provided on the inner wall of the oil tank 140 to the drive side of the timing transmission belt 25. " When the engine is in a horizontal state, and the upper part of the timing transmission belt 125 moves from the driving side to the driven side at a substantially horizontal level, even if the oil stored in the fuel tank 14 is below the timing transmission belt 125 The oil mist will also be formed by the rotation of the oil slinger 156a, 156b, and part of it will be attached to the oil droplets to attract the B guide wall 190, and the oil will form oil droplets 0, and on the driving side of the timing transmission belt 125 The upper part of the tribe is down, so the oil droplet is completely independent of the centrifugal force, and can be attached to the upper part of the timing belt 125 to run to the driven pulley 124, and patrol the upper part during this, so that the driven The pulley 124 may indeed be lubricated. At this time, if there is no oil droplet induction wall 190, most of the oil droplets formed by the slinger rings 156a, 156b will adhere to the lower side portion of the timing transmission belt 125, and below the timing transmission belt 125. The side part is driven to the upper side by the rotation of the driving pulley 12 3. The oil droplet will fly away from the timing transmission belt 125 due to the centrifugal force, and it will be difficult to reach the timing transmission belt 125. . -In this way, the lubrication system of the valve mechanism 122 is divided into two, one is the system of the timing transmission device 122a and the part of the cam device 122b in the oil and grease tank 140 scattered in the oil tank 140 and the first valve actuation chamber 121a. It is a system that lubricates the remaining cam device 122b in the second valve actuation chamber 12 lb with oil mist transmitted to the second valve actuation chamber 12 lb. Therefore, the burden of each lubrication system can be reduced, and the entire wide action mechanism 122 can be completely lubricated. . And by the oil droplets or oil mist transport -------- ^ -------- ^ --------- line (Please read the precautions on the back before filling in this (Page) -37- 530114 A7 " " ** —————————. V. Description of the invention (35) It can reliably lubricate all parts of the engine regardless of the running position of the engine. In addition, the atomized oil in the oil tank 140 is circulated by using the pressure pulsation of the crank chamber 106 and the one-way transmission function of the check valve 161, so there is no need to install another special purpose to circulate the oil mist. The oil pump can achieve the effect of simplifying the structure. In addition, not only the fuel tank 140 but also the oil delivery duct 160 connected between the crank chamber 106a and the second valve operating chamber 121b is also arranged outside the engine body 101, so it does not hinder the thinning and miniaturization of the engine body 101 , And help the effect of engine E significantly reduced weight. In particular, the external oil delivery duct! 60 is not easily affected by the heat from the engine body 101 and is easy to dissipate heat, thereby facilitating the cooling of the oil mist. In addition, the fuel tank 140 is disposed on the outside of one of the engine bodies 101, so that it can be large 1) ¾ reduce the overall surface of the engine E 'and a part of the timing transmission i22a is accommodated in the fuel tank 140, so the engine can be suppressed as much as possible. The increase of the width and width achieves the effect of miniaturization. Next, a third embodiment 0 of the present invention will be described with reference to Figs. 25 to 36. First, the outer peripheral structure of the hand-held four-stroke engine e will be described with reference to Figs. 25 and 26. Figs. A carburettor 202 and an exhaust muffler 2 03 are provided at the front and rear of the engine body 201 of the hand-held four-stroke engine E, respectively. An inlet of the carburettor 200 is provided with an air filter 204. A fuel tank 205 made of synthetic resin is provided under the engine body 201. The crank shaft 213 is attached to the engine body 201. The paper size is applicable to the Chinese National Standard (CNS) A4 specification (21 × 297 mm). Γ Please read the precautions on the back before writing. ^^ Write this page. Printed by the Bureau's Consumer Cooperatives -38-

Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs

The two outer sides of the fuel tank 24o adjoining the 201-side of the engine body protrude from both ends, and a recoil starter device 24o is installed on the outer side of the fuel tank 240, which can be driven and connected to one end of the tank. Follower member 284. The other end of the crank shaft 213 is fixed with a cooling fan -243 with a flywheel. A plurality of fixed hubs 246 are formed on the outer surface of the cooling fan 243 (only one of which is shown in FIG. 25). Each fixed hub 246 supports a centrifugal block 247 so that it can swing freely. The centrifugal block 247 and the clutch drum 248 fixed to the driving shaft 250 described later together constitute a centrifugal clutch 249 '. Therefore, once the number of rotations of the crank shaft 213 exceeds a certain straight, the centrifugal block 247 will be based on its own centrifugal force. It is crimped to the inner peripheral wall of the clutch drum 248 and transmits the output torque of the crank shaft 213 to the drive shaft 250. The diameter of the cooling fan 243 is larger than that of the centrifugal clutch 249. The engine body 201 and the engine cover 251 for covering the auxiliary equipment outside the fuel tank 205 are fixed at appropriate places on the engine body 201, and a cooling air suction port 219 is provided between the engine cover 251 and the fuel tank 205. Therefore, by the rotation of the cooling fan 243, external air can be sucked in from the cooling air suction port 219 for cooling of each part of the engine E. The engine cover 251 is fixed with a bearing bracket 258 which is coaxial with and parallel to the crank shaft 213 and has a truncated cone shape. The bearing bracket 258 supports the drive shaft 250 through a bearing 259 to drive the same repair as the first embodiment. The cutter C of the lawnmower T (refer to Fig. 1) rotates. Moreover, the engine body 201 is placed in the middle, and the fuel tank 240 and the starting device 242 are arranged on one side, and the cooling fan 243 and the centrifugal clutch 249 are arranged on the other side, so the weight of the engine E is well balanced and the engine can be made. Ε This paper size applies to China National Standard (CNS) A4 (210 X 297 mm) -39- Packing -------- Order ------ I--Line (Please read the note on the back first (Fill in this page again) 530114

V. Description of the invention (37) The center of gravity of the invention (37) is close to the central part of the engine body 201, and the maneuverability of the engine E is improved. In addition, a cooling fan 243 having a diameter larger than that of the centrifugal block 247 is fixed on the crank shaft 213 between the engine body 201 and the centrifugal block 247. Therefore, the increase in the size of the engine E due to the cooling fan 243 can be avoided as much as possible. Next, the structures of the engine body 201 and the fuel tank 240 will be described with reference to FIGS. 25 to 28, 29, 32, and 33. 25 to 28, the engine body 201 includes a crank case 206 having a crank chamber 106a, a cylinder block 207 having a cylinder hole 207a, and a combustion chamber 208a and intake and exhaust openings in the chamber 208a. The cylinder heads 208 of the valves 209 and 210 are formed on the outer periphery of the cylinder block 207 and the cylinder head 208 and a plurality of fins 238 are formed. The crank shaft 213 housed in the crank chamber 206a is supported on the left and right side walls of the crank case 206 by ball bearings 214, 214, and can be rotated freely. At this time, the ball bearing 214 on the left is provided with an oil seal, and the ball bearing 214 'on the right is provided with an oil seal 217 on the outside. As is conventional, the crank shaft 213 is connected to a piston 215 fitted in the cylinder bore 207a through a connecting rod 216. The left side wall of the crank case 206 and the oil tank 240 adjacent to the outside thereof are integrally connected, and the end of the crank shaft 213 with an oil-sealed ball bearing 214 side is arranged to pass through the oil tank 240. An oil seal 239 is installed on the outer side wall of the oil tank 240 penetrated by the crank shaft 2 13. The top wall of the fuel tank 240 is integrally provided with a belt guide cylinder 286 having a flat cross-section, which extends through the wall and extends upwards and downwards while opening the upper and lower ends. The paper size is applicable to Chinese National Standard (CNS) A4 (210 X 297 male). (%) (Please read the notes on the back before filling this page) · ---. Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs -40- 530114 A7 ______B7___ 5. Description of the invention (%) (Please read the notes on the back first Matters, please fill out this page). The lower end of the belt guide cylinder 286 extends to the vicinity of the crank shaft 213 in the fuel tank 240, and the upper end is integrally connected to the cylinder head 208, and includes a partition wall 285 together with the cylinder head 208. A series of annular oil seal protrusions 287 are formed on the cylinder head 208 and the upper edge of the belt guide cylinder 286, and the partition wall 285 protrudes above the oil seal protrusions 287. In addition, as shown in FIG. 29, FIG. 32, and FIG. 33, an annular oil seal groove t 288a corresponding to the aforementioned oil seal protrusion 287 is formed on the lower end surface of the cylinder head 236, and is also formed on the inner surface of the cylinder head 236 There is a linear oil seal groove 288b for communicating between the two sides of the annular oil seal groove 28 8a. The annular oil seal groove 28 8a is provided with a ring seal packing 289a, and the linear oil seal groove 288b is provided with a ring seal. Shaped Sealing Packing 289a—Body-formed Linear Sealing Packing 289b. In addition, the cylinder head 236 is combined with the cylinder head 208 by bolts 237, so that the annular seal packing 289a is crimped to the oil seal protrusion 287, and the linear seal packing 289b is crimped to the partition wall 285, respectively. In addition, the belt guide cylinder 286 and the half of the cylinder head 236 are divided into the first valve actuation chamber 221a, and the cylinder head 208 and the other half of the cylinder head 236 are divided into the second valve actuation chamber 221b. The chambers 22a, 221b are separated by the aforementioned partition wall 285. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs. In Figures 25 to 28, the engine body 201 and the fuel tank 240 are on a plane that passes through the axis of the crank shaft 2 13 and is orthogonal to the axis of the cylinder bore 2 7 a. In the above, 2 is divided into an upper block Ba and a lower block Bb. That is, the upper block Ba is composed of the upper half of the crank phase 206, the cylinder block 207, the cylinder head 208, the upper half of the fuel tank 240, and the belt guide cylinder 286, and the lower block Bb is composed of a crank. The lower half of the tank 206 and the lower half of the fuel tank 240 are integrally connected to form this paper. The size of the paper applies to the Chinese National Standard (CNS) A4 (210 X 297 mm) -41- 530114 A7

V. Description of the invention (39), these upper and lower blocks Ba and Bb are individually prayed, and after each part is processed, a plurality of bolts 212 (refer to FIG. 27) are used to exchange each other I tj ,, The port name is on the cylinder head 208 and is provided with an intake valve 218i and an exhaust valve 218e for opening and closing the intake port 209 and the exhaust port 210, respectively, which are formed with the axis of the gas rainbow hole 207a. In a parallel configuration, the Mars plug 220 is screwed to the electrode near the center of the combustion chamber 208a. The a is a valve operating mechanism 222 for opening and closing the intake valve 218i and the exhaust valve 218e as described above with reference to Figs. 26 to 30. The valve actuating mechanism 222 is a timing transmission device 222a arranged from the oil tank 240 across the aforementioned valve operating chamber 221a, and a cam device arranged from the aforementioned first valve operating chamber 221a across the second valve operating chamber 221b. 222b. The timing transmission device 222a includes: a driving pulley 223 fixed on a crank shaft 213 in the fuel tank 240, a driven pulley 224 supported on the upper part of the belt guide cylinder 286 so as to be freely rotatable, and wound thereon. The timing transmission belt 225 between the driving and driven pulleys 223 and 224; and the end surface of the driven pulley 224 on the side of the partition wall 285 is integrated with the cam 226 constituting a part of the cam device 222b. In this way, the cam 226 is arranged on one side of the cylinder head 208 together with the driven pulley 224. The driving and driven pulleys 223 and 224 are toothed, and the driving pulley 223 drives the driven pulley 224 by a belt 225 with a speed reduction ratio of 1/2. A support wall 227 is integrally formed on the outer side wall of the belt guide cylinder 286 and stands inside the annular oil seal protrusion 287 and contacts or approaches the inner surface of the cylinder head 236, and a through hole 22 is provided in the support wall 22 7 8a and bottomed hole 228b provided on the partition wall 285 and both ends of the supporting shaft 229 are free. The paper size is applicable to China National Standard (CNS) A4 (210 X 297). (Please read the back Note on this page) Order. Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs-42- 530114 Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs

A7 B7 Description of the invention (40) The state of rotation, and the aforementioned driven pulley 224 and cam 226 are supported in the middle part of the support shaft 229, so that it can rotate freely. The support shaft 22 9 is inserted into the bottom hole 228b through the through hole 228a before the installation of the cylinder head 236 through the driven pulley 224 and the shaft hole 235 of the cam 226. After the insertion, the cylinder head 236 is joined to the cylinder head 20 8 and the belt guide cylinder 286, the inner surface of the cylinder head 236 is opposite to the outer end of the shaft 229, which can prevent the effect of falling off. The partition wall 285 is integrally formed with a pair of bearing sleeves 230i and 230e which are parallel to the support shaft 229 and protrude from the 22lb side of the second valve operating chamber, and the cam device 222b includes: the aforementioned cam 226; and the respective supporting sleeve 230i The 230 and 230e are freely rotatable inlet rocker shafts 23 li and exhaust rocker shafts 231e; they are fixed to one end of the rocker shafts 23 li and 23 le in the first valve operating chamber 221a and have front ends The intake cam follower 232i and the exhaust cam follower 232e slidably connected below the cam 226 are fixed to the intake and exhaust rocker arm shafts 23 li and 231 e in the second valve actuation chamber 221b, respectively. An intake rocker arm 233i and an exhaust rocker arm 233e at one end of which the front end portion is in contact with the upper ends of the intake valve 218i and the exhaust valve 218e; and are provided on the intake valve 218i and the exhaust valve 218e to give them The intake spring 234i and the exhaust spring 234e having potential energy toward the valve closing direction are waited. The above-mentioned support shaft 229 and the intake and exhaust rocker arm shafts 23 and 231 are arranged at positions higher than the annular oil seal protrusion 287 at the upper end of the cylinder head 208 and the belt guide cylinder 286. When the crank shaft 213 rotates, the driving pulley 223 that rotates with the crank shaft 213 rotates the driven pulley 224 and the cam 226 through the belt 225, and the cam 226 shakes the intake and exhaust cam followers 232i and 232e in a timely manner. And this paper size is applicable to China National Standard (CNS) A4 specification (210 X 297 mm) ^ -------- ^ --------- ^ (Please read the notes on the back first (Fill in this page again) -43- 530114 A7 — B7 V. The description of the invention (") is transmitted to the intake and exhaust rocker arms 233i and 233e through the corresponding rocker arm shafts 231i and 231e and made After shaking, the air intake and exhaust springs 234i and 234e can be coordinated to open and close the intake and exhaust valves 218i and 218e in a timely manner. The driven pulley 224 and the cam 226 are connected to The support shaft 229 is supported to be freely rotatable, and the support shaft 29 is also supported on the two side walls of the valve actuating chamber 221 a to be freely rotatable. Then, the driven pulley 224 and the cam 226 are rotating, because The frictional drag causes the support shaft 129 to rotate, thereby reducing the rotation speed of the driven pulley 224 and the cam 226 and the support shaft 229 It can achieve the effect of reducing the wear of the rotating sliding part and help improve its durability. Moreover, the cam 226 with a larger diameter is arranged on one side of the cylinder head 208 together with the driven pulley 224, and the cylinder head 208 Just above the intake and exhaust rocker arms 233i and 233e and the smaller diameter intake and exhaust rocker arms 23 li and 23 le, the valve actuation mechanism 222 will not increase the volume significantly above the cylinder head 208 ' And reduce the overall height of the engine E, which can contribute to the miniaturization of the engine E. In addition, the support shaft 229 and the intake and exhaust rocker arm shafts 231i and 231 e are arranged in a series of loops more than the cylinder head 208 and the upper end of the belt guide cylinder 286. The oil seal protrusion 287 is at a high position. Therefore, when the cylinder head 236 is removed, the oil seal protrusion 287 will not cause any obstruction, and it can be combined and disassembled above the support shaft 229 and the intake and exhaust. The rocker shafts 23 li and 23 le are extremely good in assemblability and maintenance. Secondly, the lubricating device of the engine E will be described with reference to FIGS. 26 to 34. The lubricating device of the engine E is shown in FIGS. 27 and 28. The standard used to lubricate this paper is applicable to Chinese national standards ( CNS) A4 size (210 X 297 mm) (Please read the precautions on the back before this page). Line. Printed by the Consumers ’Cooperative of the Intellectual Property Bureau of the Ministry of Economy 530114 Printed by the Consumer ’s Cooperative of the Intellectual Property Bureau of the Ministry of Economy A7 B7 5 4. Description of the invention (42) Around the crank shaft 213, namely the first lubrication system La dedicated to the crank shaft 213, the bearings 214, 214, the connecting rod 216 and the piston 215, and the second lubrication system Lb used to lubricate the valve operating mechanism 222 And the fuel tank 240 is common to these systems La and Lb. The oil tank 240 stores a self-supplying oil port 240a for injecting a predetermined amount of lubricating oil. A crank shaft 213 in the oil tank 240 is fixed with a pair of holding the driving pulleys 223 in parallel with each other in the axial direction. Sling rings 256a, 256b. The slinger rings 256a and 256b extend toward each other in the opposite direction, and meanwhile, the front end is bent toward the axis facing away from each other. Once the crank shaft 213 is driven to rotate, the two slingers no matter the engine e is in any running posture. At least one of the rings 256a and 256b will stir the oil stored in the oil tank 240 and scatter it to form an oil mist. First, the first lubrication system La includes a first oil passage 26 () provided on the crank shaft 213 and used to communicate the crank chamber 206a with the oil tank 240, and used to communicate the bottom surface of the crank chamber 206a with the oil tank 240. The second oil passage 2602, and the second oil passage 2602 is provided with a one-year-old first directional valve 261 on the opening facing the crank chamber 206a. The first-directional valve 261 is raised and lowered with the piston 215 The crank chamber 206a is closed when it is in a depressurized state, and is opened when it is boosted. The first and second oil paths 260 and 2602 are respectively oriented toward the open ends 260 in the fuel tank 240a and 260 #. It may be arranged near the central part of the fuel tank 240, and the open ends 260a and 2602a may be exposed on the oil surface of the storage oil 0 regardless of the posture of the engine E. Second, the second lubrication system Lb is A third oil passage 2603 is provided on the engine body 201 and communicates with the middle portion of the first valve actuation chamber 221a and the bottom surface of the second valve actuation chamber 22lb. It is formed on the cylinder head 236 and communicates with the second valve actuation chamber. 22 lb This paper size applies to China National Standard (CNS) A4 (210 X 297 mm) -45- ^ -------- ^ --------- ^ (Please read the precautions on the back before filling this page) 530114 A7 B7 Printed by the Consumers' Cooperative of Intellectual Property Bureau of the Ministry of Economic Affairs V. Oil recovery chamber 274 of the invention description (43), which is installed in the engine body 201 and is used to communicate the oil recovery The fourth oil passage 2604 of the chamber 274 and the crank chamber 206a, the aforementioned second oil passage 2602, and the second oil passage provided at the opening of the third oil passage 2603 toward the second valve actuation chamber 22lb. The directional valve 262 is configured, and the second directional valve 262 is closed when the crank chamber 206a is in a decompressed state as the piston 215 is raised and lowered, and is opened when the pressure is increased. As shown in FIGS. 28, 32 and As shown in FIG. 33, on the top wall of the gas red cover 236, a partition plate 265 of the ventilation chamber 269 is drawn on the upper part of the cover 236, and a plurality of pillars 266 protruding from the top wall are engaged with it. The clip 267 is installed 'and the ventilation is to 269 ^ — the aspect is the large gap between the peripheral edge of the partition plate 2 6 5 and the inner peripheral surface of the gas red cover 2 3 6, that is, the communication portion 268 (refer to FIG. 32), and It communicates with the second valve actuating chamber 22lb, and communicates with the air cleaner 204 through a vent pipe 27o. The air chamber 169 is used for gas-liquid separation of mixed oil and channel gas mixture. The partition plate 265 is connected with a box-shaped spacer 279 which defines the oil recovery chamber 274 between the upper surface and the upper surface. On the partition plate 265, a plurality of siphon pipes 275 (four in the example shown in the figure) are spaced apart from each other and communicate with the oil recovery chamber 274 respectively. The front ends of the siphons 275 extend to the vicinity of the bottom surface of the second valve operating chamber 221b, and the openings at the respective front ends form holes 275a. On the upper wall of the spacer 279, a plurality of siphon pipes 276 (three in the example shown in the figure) are spaced apart from each other and communicate with the oil recovery chamber 274 respectively. The front ends of the siphons 276 extend to the vicinity of the top surface of the ventilation chamber 269, and the front end openings are formed with holes 27. (Please read the precautions on the back before this page) -Body. --Line · -46- A7

Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs

530114 V. Description of the invention (44) In the partition plate 265 and the spacer 279, apertures 280 and 283 for communicating the oil recovery chamber 274 to the second valve operating chamber 221b and the venting chamber 269 are respectively formed. The integrated dog on the 1¾ board 265 does not have a conduit 281 for communicating with the oil recovery chamber 274. The front end of the conduit 281 is protruded and opened by the grommet 282 and the bottom surface moved from the second valve to 22 lb. The upper ends of the fourth oil passages 2604 are joined. In this way, the recovery chamber 274 is connected to the fourth oil path 2604. Explain the role of the lubrication device of the engine E. During the operation of the engine e, the oil tank 240 and the crankshaft 213 serve as rotating oil throwing rings 256a, 256b, that is, the stored oil 0 is stirred and scattered to form an oil mist. The oil tank 240 and the first valve operating chamber 221a opened at the upper portion thereof are filled with oil mist. Therefore, the oil mist can directly lubricate the timing transmission device 222a accommodated in the first valve operating chamber 221a. In addition, in the crank chamber 206a, pressure pulsations of pressure increase and decompression are repeatedly generated due to the rise and fall of the piston 215. With this, the oil mist formed in the fuel tank 240 travels back and forth between the fuel tank 240 and the crank chamber 206a. The oil mist introduced into the crank chamber 206a is used to lubricate around the crank shaft 213, that is, the crank shaft 21, the bearings 214'214 /, the connecting rod 216, and the piston 215. At this time, the first directional valve 261 is closed when the crank chamber 206a is depressurized and opened when the pressure is increased, and a part of the positive pressure component of the pulsating pressure is discharged to the oil tank 240 through the second oil path 2602. The crank chamber 206a liquefies and accumulates at the bottom of the chamber 206a, and returns to the fuel tank 240 through the second oil path 2602 together with the positive pressure. Also, the pressure pulsation of the crank chamber 206a will also move through the fuel tank 240, the first valve to 221a, and the third oil path 2603 to affect the second-directional valve 262. Since the second-directional valve 262 is also at The crank chamber 206a is closed when depressurized and opened when pressure is increased. When the valve is opened, the oil mist in the fuel tank 240 is sequentially transmitted to the first paper standard applicable to the Chinese National Standard (CNS) A4 specification (210 x 297 mm). Μ -------- ^ -------! Line {Please read the precautions on the back before filling out this page} -47- 530114 V. Description of the invention (#) 1Valve chamber 221a, No. The 3 oil passage 2603 and the second valve operating chamber 221b lubricate the timing transmission device 222a in the first valve operating chamber 221a, and the cam device 222b in the second valve operating chamber 221b. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs, the crank chamber 206a discharges the positive pressure component of the pressure pulsation from the first directional valve 261 to the fuel tank, which is an average negative pressure state, and through the fourth oil circuit 26. 4 And the oil recovery chamber 274 communicating with the crank chamber 206a is also in a negative pressure state. On the other hand, the ventilating chamber 269 is connected to the air filter 204 through the venting pipe 270 'even though the engine E is running, the atmospheric pressure is maintained substantially, and the communicating portion 268 is connected to the first of the venting chamber 269. The 2-valve operating chamber 22 lb is also in a state of almost atmospheric pressure. As a result, the pressure of the second valve actuating chamber 22 lb and the venting chamber 269 is transmitted to the oil recovery chamber 274 'through the siphons 275 and 276 and the orifices 280 and 283. Then the oil mist in the second valve actuating chamber 22 lb and the venting chamber 269 It is also transferred to the oil recovery chamber 274 as the pressure moves. In particular, when the engine E is in the upright state, the oil that has been liquefied in the second valve actuating chamber 22 lb and accumulated on the bottom thereof is sucked by the siphon 275 near the bottom and transported to the oil recovery chamber 274. In the inverted state, liquefaction in the venting chamber 269 accumulates on the bottom, that is, the oil on the top surface of the cylinder head 236, is sucked by the siphon pipe 276 near the top surface and transported to the oil recovery chamber 2 7 4. In this way, the oil recovered in the oil recovery chamber 274 is transferred to the crank chamber 206a via the fourth oil path 2604, and thereby the periphery of the crank shaft 213 can be lubricated. Therefore, the lighter load timing transmission device 222a and cam device 222b are only lubricated by the oil mist introduced from the oil tank 240 into the first and second wide moving chambers 221a and 22lb, so the amount of lubricant is small, which can be avoided. Transition lubrication. In addition, the crank shaft 213 is surrounded by the oil mist introduced into the crank chamber 206a from the oil tank 240, and the paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297 mm). Printed by the cooperative 530114 A7 ___ B7 V. Description of the invention (46) After lubricating the cam device 222b, the oil mist and liquefied oil recovered to the oil recovery chamber 274 and lubricated, the amount of the lubricating oil is large, and the load can be large. The crank shaft 2 13 is properly lubricated around. In this way, the periphery of the crank shaft 213 and the valve mechanism 222 are respectively lubricated with an oil circulation amount corresponding to the magnitude of its negative load, so the oil storage amount in the oil tank 240 can be less than that known, thereby promoting the oil tank. 240, and the entire engine E is small and lightweight. In addition, the oil mist in the fuel tank 240 is circulated by using the pressure pulsation of the crank chamber 206a, and the one-way transfer function of the first and second directional valves 261 and 262. The special oil pump for circulation can achieve the effect of simple structure. The blow-by gas mixture generated in the crank chamber 206a is transferred to the oil tank 240 through the first oil passage 26〇1, and then sequentially passes through the jth valve actuation chamber 221a, the third oil passage 2603, and the first with the oil mist. The two-valve operating chamber 221b is transmitted to the ventilation chamber 269, and the gas-liquid separation is performed in the chamber 269. When the blow-by gas mixture separated from the oil is in the stroke of the intake air of the engine E, it is sequentially passed through the ventilation pipe 27 and the air. Filter | 204 while sucked into engine E. In addition, if the fuel tank 240 is shown in FIG. 35 and the engine E is in an inverted state, or when it is in an inverted state as shown in FIG. 36, the stored oil 〇 will be moved to the top side of the fuel tank 240 or Side, and the open end of the first valve actuating chamber 221 & towards the fuel tank 240 is set by the belt guide cylinder 286 to be always higher than the liquid level of the stored oil 0, so the stored oil will not be made 〇 Flowing into the second valve operating chamber 221b can prevent excessive oiling of the timing transmission device 222a, and at the same time can ensure that the amount of oil in the fuel tank 240 is within a prescribed amount, and oil mist can continue to be formed by the oil slingers 256a, 256b. This paper size applies to China National Standard (CNS) A4 specifications ⑽ X 297 meals) --- ^ -------- ^ --------- ^ {Please read the precautions on the back before filling This page} -49- 530114 A7 --------- B7_____________ V. Description of the invention (47) In addition, because the fuel tank 240 is arranged on the outside of the engine body 201 ~ 1, the engine E can be greatly reduced. The overall height, and a part of the timing transmission device 222 & is housed in the fuel tank 240, which will greatly suppress the increase of the engine's width, thereby achieving the effect of small size and light weight. In addition, in the aforementioned third embodiment, the middle part of the first valve actuating chamber 2 2 1 a is connected to the third oil path 26403, and the upper part of the first valve actuating chamber 221a may be connected to the third oil. Road 2603. The present invention is not limited to the foregoing embodiments, and various design changes can be made without departing from the gist thereof. For example, in the foregoing embodiments, the timing transmission device is a belt type, but a chain type timing transmission device may also be used. (Please read the notes on the back first

· -Line · Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs -50- This paper size applies to China National Standard (CNS) A4 (210 X 297 mm) E ... Handheld four-stroke engine T ... Power lawn mower C ... Cutter 0 ... Oil La ... 1st lubrication system Lb ... 2nd lubrication system Ba ... Upper block Bb ... Lower block g ... Clearance 1, 101, 201 ... Engine body 2, 102, 202 ... Carburetor 3, 103, 203 ... Exhaust muffler 4, 104, 204 ... Air filter 5, 105, 205 ... Fuel tank 6, 106, 206 ... .Crank case 6a, 106a, 206a ._. Crank chambers 6L, 6R ... 1st, 2nd case half 7, 107, 207 ... Cylinder block 7a, 107a, 207a ... Cylinder bore 8, 108, 208 ... Cylinder heads 8a, 108a, 208a ... Combustion chambers 9, 109, 209 ... Intake ports 10, 110, 210 ... Exhaust ports 530114 A7 B7 V. Description of the invention (48 [ Component reference table] 12, 112, 212 ... Bolts 13, 113, 213 ... Crankshaft 14, K; 114, 114; 214, 214, Ball bearings 15, 115, 215 ... Piston 16, 116, 216 ... Connecting rod 17, 17 < ... Oil seal device 18, 118i, 218i ... Intake valve 19, 118e, 218e ... Exhaust valve 20. Mars plug 21. Valve actuated cam chamber 22, 23 ... Valve spring 24, 25 ... Cam follower 26, 126 '226 ·· Camshaft 27, 27 /… Ball bearing 28… Oil seal 29 " .Inlet 30 ..... Side cap 31 ... Oil seal member 32 ... Drive pulley 33 ... Driven pulley 34 ... Timing transmission belt 35, 122a, 222a ... Timing transmission device This paper size is applicable to China National Standard (CNS) A4 specification (210 X 297 mm) -------- ^ ------- -(Please read the notes on the back before filling out this page) Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs-51- 530114 A7 B7 Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs ... belt covers 37, 137, 237 ... bolts 38, 138, 238 ... heat sinks 39, 3V ... oil seals 40, 140, 240 ... fuel tanks 41 ... bolts 42, 142, 242 ... starting Devices 43, 143, 243 ... Flywheel (cooling fan) 44 ... Nuts 45 ... Cooling blades 46, 146, 246 ... Fixed hubs 47, 147, 247 ... Centrifugal blocks 48, 148, 248 ... Clutch drums 49 149, 249 ... Centrifugal clutches 49, 149, 249 ... Power output mechanism 50, 150, 250 ... Drive shafts 51, 15 and 251 ... Engine covers 51a, 51b ... 1st, 1st 2 cover half 52 .. air inlets 53, 122, 222 ... valve mechanism 54 .. base 55 " port 56 ... slinger 56a, 56b ... blade 57 ... nut 58, 158, 258 ... bearing brackets 59, 159, 259 ... bearings 60, 160 ... oil delivery conduits 61, 161 ... check valves 62 ... valve chambers 63 ... inlet pipes 64, 67 ... Connection hole 65 ... Oil seal member 66 .. Outlet pipe 68 .. Gas-liquid separation passage 68a, 68b .. Horizontal hole, vertical hole 69, 169, 269 ... Ventilation chamber 70, 170, 270 ... Ventilation pipe 71 ... Cylinder head 72 ... Oil seal member 73 ... Orifice 74 ... Suction chambers 75, 76; 175, 176; 275, 276 ... Siphon tube 78 ... Oil return tube 80 ... Inlet tube 81 ... Connector 82… Outlet tube 83 .. Oil return hole (please read the precautions on the back first --- this page: --line-this paper size applies to China National Standard (CNS) A4 (210 X 297 mm) ) -52- 530114 A7 B7 V. Description of Invention (5G) Employees' cooperation on intellectual property of the Ministry of Economic Affairs Printed (Please read the precautions on the back before filling in this page) 84, 184, 284 ... Driven members 117, 217 ... Oil seals 119, 219 ... Cooling air suction ports 121a, 221a ... First valve actuation chamber 121b , 221b ... 2nd valve actuating chambers 122a, 222a .... Winding timing gears 122b, 222b ... Cam devices 123, 223 ... Drive pulleys 124, 224 ... Driven pulleys 125, 225 ... Winding member (timing drive belt) 125a ... Upper side parts 126, 226 ... Cams 127, 227 ... Support walls 128a, 228a ... Through holes 128b, 228b ... Bottom holes 129, 229 ........ support shafts 130i, 130e; 230i, 230e ... bearing sleeves 131i, 231i ... intake rocker shafts 131e, 231e ... exhaust rocker shafts 132i, 232i ... intake cam followers 132e, 232e ... exhaust cam followers 133i, 233i ... intake rocker arms 133e, 233e ... exhaust rocker arms 134i, 234i .... intake springs 134e, 234e .... exhaust springs 135, 235 Shaft holes 136, 236 ... Cylinder heads 139 ... Oil seals 140a, 240a ... Oil supply ports 155, 255 ... Ports 155a, 255a ... Open ends 156a, 156b; 256a, 256b ... Oil slinger (oil mist formation Installation, oil droplet formation device) 161 ... transmission device (valve device) 162a ... lower connection pipe 162b ... upper connection pipe 163 ... communication path 164 ... bypass pipe 165, 265 ... partition 165a ... Depressions 166, 266 ... Pillars 167, 267 ... Clips 168 ... Connected pipes 172 ... Baffles 174, 274 ... Oil recovery chambers 175a, 275a ... Holes 176a, 276a ... Orifice 178 ... Return oil channel-53- This paper size is applicable to Chinese National Standard (CNS) A4 specification (210 X 297 mm) 530114 _B7 V. Description of the invention (51) 178a ... Entrance 179, 279 ... interval Body 180, 280 ... Orifice 181, 281 ... Duct 181a ... Orifice 182, 282 ... Grommet 185, 285 ... Partition wall 186, 286 ... Belt guide tube 187, 287 ... Ring Oil seal protrusions 188a, 288a ... annular oil seal grooves 188b, 288b ... linear oil seal grooves 189a, 289a ... annular seal packings 189b, 289b ... linear seal packing 190 ... oil drop induction wall 223 ... Driven rotating member 224 ... Driven rotating member 260 !, 2602 ... 1st and 2nd oil circuits 2603, 2604 ... 3rd and 4th oil circuits Intellectual Property Bureau, Employees' Cooperatives Printing 260 #, 2602a ... · Open end 261 ··· 1st oil delivery device (1st-directional valve) 262 ··· 2nd oil delivery device (2nd-directional valve) 283 .. · 口 口 -54- This paper size is applicable to China Standard (CNS) A4 specification (210 X 297 mm)

Claims (1)

530114 A8 B8 C8 D8 Patent application scope fl No. 90105844 Application patent scope amendment V August 30, 91 1. A hand-held four-stroke engine, including: an engine body (Bu 10bu 201), Crank case (6, 106, 206) with a crank chamber (6, 10, 206a), cylinder block (7, 107, 207) with a cylinder bore (7a, 107, 207a), and The cylinder head (8, 108, 208) of the air port (9, ι09, 209) and the exhaust port (10, 110, 21); a crank shaft (13, 113, 213), which is supported by the crank case (6, ι06, 206) and contained in the crank chamber (6a, 106a, 206a); a piston (15, 115, 215), which is embedded in the gas The red holes (7a, 107a, 207a) are connected to the crankshaft (13, U3, 213) at the same time; an intake valve (18, 118.i, 218i) and an exhaust valve (19, 118e) 218e) are installed on the cylinder head (8, 108, 208) to open and close the air inlet (9, 109, 209) and the exhaust (10, 110, 210); a valve actuating mechanism ( 53, 122, 222), which can be linked to the crank shaft (13, 1 13,213) are rotated to drive the intake valve (18, 118i, 218i) and exhaust valve (19, 118e, 218e) to open and close; a power output mechanism (49, 149, 249 >) is provided on the crank The shaft (13, 113, 213) protrudes from the outer end of the engine body (i, 101, 201); and a fuel tank (40, 140, 240); characterized by the valve mechanism (53, 122, 222) Causes: One is supported on the cylinder head (8, 108, 208), and can rotate freely. The paper size is applicable to China National Standard (CNS) M specification (21〇 × 297 mm) (Please read the precautions on the back first) Fill out this page) Order 1- · •• Line- -55- 530114 VI. Patent application scope B, 2l8i) Camshaft (26, lean-out mechanism (49, 3, 113, 213) L moving device (35,, 101 , 201) Yu send cold wind per power output: 213) tops, flywheels (43, equal timing transmissions, W, 240) support &, where the positive handle chamber (6) phase i engine, which And: a lubricating oil is used to configure a use part, in which the positive connection of the valve 1, 201) is called ----------- 丨 called Duping⑽) M specifications ( 21GX297) '' ~ -56- 530114 A8 B8 C8 D8 Patent application scope M Special-purpose agricultural farm (122a, 222a), and the rotation force of the driven side of this timing transmission (ma, 222a) is transmitted to the The air valve and the exhaust valve (118i, 2181, 118.218) are constituted by a cam device (122, 222b) as one of their opening and closing forces, and the first valve action that houses this timing transmission device (12, 22h) To (121a, 221a) are connected to the fuel tanks (14, 24), and the second valve operating chamber (121b, 221b) containing at least a part of the cam device (丨 22b, 222b) is formed in On the cylinder heads (108, 208); in addition, a pair of oil slingers (156125 抛; 1561), 256b are fixed on the crank shaft (113, 213) to hold the timing gear (1223, 222 &). ), The pair of oil slingers (156a, 25 仏; 15 讣, 256b) are used to stir the oil (〇) stored in the oil tanks (140, 24), so as to scatter and form an oil mist to supply the second Valve actuation chambers (121b, 221b) and crank chambers (106a, 206a). 5. If the four-stroke engine of item 4 of the patent application scope, the crankshaft (113, 213) is provided with a port (155, 255) to supply the oil mist generated in the fuel tank (140, 240). To the crank chamber (106 &, 20a), and the open ends (155a, 255a) of the ports (155, 255) facing the fuel tank (i4〇, 24) are arranged in the timing transmission (122 &;, 222a) and the slinger (156a, 156b). 6. If the handheld four-stroke engine of item 4 of the scope of patent application, the belt guide cylinders (186, 286) containing timing transmissions (122, 222) are integrally connected with the fuel tanks (140, 240), and The belt guide cylinders (186, 286) protrude from the oil at the open ends facing the fuel tanks (140, 240) (please read the precautions on the back before filling this page) .Order — .. line 丨 -57- W0114 A8 B8 C8 D8, patent application scope phase (140, 240) center side, and the structure is configured to open the open end to the storage oil regardless of upside down or horizontal position (〇) Those on the surface. 7 'If the handheld four-stroke engine in item 4 of the patent application scope, wherein the other end of the crank shaft (113, 213) faces the fuel tank (14, 240) and in the fuel tank (140, 240), The timing transmission devices (122a, 222a) of the valve mechanism (122, 222) are connected to the crank shafts (113, 213), and the timing transmission devices (122a, 222a) are lubricated with the oil in the oil tanks (140, 240). )By. 8. If the four-stroke engine of item 7 of the scope of patent application, the cooling fan (143, 249) having a diameter larger than that of the power output mechanism (149, 249) is fixed to the crankshaft (113, 213) as the aforementioned cooling blade. 243). 9. If the four-stroke engine of item 7 of the scope of patent application, a cam device (122b, 222b) is arranged in a valve actuating chamber (121b, 221b) provided on the cylinder head (108, 208), The rotation of the driven side of the timing transmission device (122a, 222a) is transmitted to the intake valve and exhaust valve (丨 丨, 218i; ll8e, 218e) as its opening and closing force; and on the crank shaft (ιΐ3, 213) Those oil mist forming devices (156a, 256a; 15a, 25 讣) are connected to generate oil mist in the oil tanks (MO, 240), and are supplied to the valve operating chambers (121b, 221b). 10. The handheld four-stroke engine in item 4 of the patent scope, wherein the timing transmission device (122a, 222a) of the valve mechanism (i22, 222) is a coil with a winding member (125, 225). For the winding type, the driving side of the winding member (125, 225) is set facing the fuel tank (14, 240), and the paper tank (14, 24) is set to the paper size Applicable to China National Standard (CNS) Α4 specification (210 X 297 cm) (Please read the precautions on the back before filling this page) ·, ^ τ—: line— -58- 530114 A8 B8 C8 D8 The oil droplet formation device (156a, 256a; 15 still, 256b) that generates oil droplets, and spread the oil stored in it to lubricate the aforementioned timing (please read the precautions on the back before filling this page). (122a, 222a), and there is no oil drop induction wall (190) protruding from the inner wall of the fuel tank ("ο, 240), which is used to induce the attached oil droplets to drip when the engine (E) falls down. The aforementioned timing transmission waves (122a, 222a) face the part of the fuel tank (14, 240). 1 1. The handheld four-stroke engine according to item 1 of the patent application scope, wherein the wide-moving mechanism (122) is an oil tank installed on the outside of the engine body (101) for storing lubricating oil (0). (140), a first valve actuation chamber (121a) formed by extending the oil tank (14) above it, and a second valve actuation chamber (121b) formed in the cylinder head (108); The fuel tank (140) and the crank chamber (106a) are connected through a port (155), and the crank chamber (106a) and the second valve operating chamber (121b) are connected outside the engine body (101). The oil delivery duct (16) is connected, and the second valve operating chamber (121b) and the oil tank (140) are connected by a return oil passage (178). Furthermore, a fuel tank (140) is provided for storing An oil mist forming device (156a, 156b) that stirs the oil (〇) and scatters to generate oil mist, and also has a transmission device (161) connected to the oil delivery duct (160), so that the oil tank (140) The oil mist is transmitted to the oil delivery guide (160) through the crank chamber (106a), and the valve movement in the first valve operating chamber (121a) can be lubricated by the scattered oil in the fuel tank (14). (122) and lubricates the valve operating mechanism (122) in the second valve operating chamber (121b) with oil mist transmitted by the oil delivery guide (160) to the second valve operating chamber (121b). Patent application scope 12 · If the patent application scope item n of the four-stroke engine lubricating device, the transmission device is constituted by a valve device (161) which can close the oil delivery duct ⑽ in the crank chamber (106a), and The person who opens the catheter (160) is expected. 13. If the four-stroke engine lubricating device according to item i! Or item 12 of the patent application scope, wherein the oil delivery pipe (160) and the return oil passage (178) are connected by a bypass pipe (164). 14. The handheld four-stroke engine according to item 丨 of the patent application, wherein the valve actuating mechanism (222) is a timing transmission device formed by driving a rotating member (223) connected to a crank shaft (213) ( 222a), and used to transmit the rotational force of the driven rotating member (224) of the 4 timing transmission (222a) to the intake valve and exhaust valve (118i, 218i, U8e, 218e) as its opening and closing force A cam device (222b) is formed; a first valve actuating chamber (221a) for accommodating the timing transmission device (222a) is provided on the side of the engine body (201), and an opening is formed in the first valve actuating chamber (221a) An oil mist forming device (256a, 256b) is provided at the lower end and an oil tank (24o) for storing the oil (0) into the oil mist is provided inside the upper part of the engine body (201). (221a) the second valve actuating chamber (221b) for accommodating the cam device (222b); and the first and second oil passages (260) connected in parallel between the oil tank (240) and the crank chamber (206a) !, 26〇2), and the oil mist formed in the fuel tank (240) from the fuel tank (240), via the first oil path (26〇i), the crank chamber (206a) And the first oil delivery device (261) of the second oil circuit (2602) circulating back to the oil tank (240) constitutes the first lubrication system (La); this paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297 mm) -60- ^ 30114 A8 B8 C8 D8 The scope of the patent application is again 'by the third oil circuit (26〇3) connected between the first and second valve actuation chambers (221a, 221b), and The fourth oil passage (26〇4) between the second valve operating chamber (221b) and the crank chamber (206a), as well as the aforementioned second oil passage (26〇2) and the oil mist formed in the oil tank (240). The fuel tank (24) passes through the first valve operating chamber (221a), the third oil passage (26〇3), the second wide operating chamber (221b), the fourth oil passage (2604), and the crank chamber (206a). ) And the second oil passage (2602) circulate and return to the oil tank (240), and the second oil delivery device (262) constitutes a second lubrication system (Lb). 15. The handheld four-stroke engine of item 14 in the scope of patent application, wherein the first oil delivery device is set to a second oil passage (26〇2) and is closed when the crank chamber (206a) is decompressed, The first-direction wide (261) opened when boosting, and the second oil delivery device is installed in the third oil path (26〇3) and decompressed in the crank chamber (206a). The second directional valve (262) which is closed and opened at the time of boosting is constituted. (Please read the precautions on the back before filling in this page) 丨 *! Order- 丨 *-; Line 丨 This paper size is applicable to China National Standard (CNS) A4 (210X297 mm) -61- 530114