Small silent engine for chain saw

Abstract

The utility model provides a small silent engine for a chain saw, which relates to the technical field of chain saw engines and comprises an engine cylinder body, a crankcase and a balance flywheel, the crankcase is fixed at the tail of the engine cylinder body, the balance flywheel is arranged in the middle of the crankcase, and buffer rubber blocks are arranged on the upper portion and the lower portion of the head end of the engine cylinder body respectively. The center of the balance flywheel is fixedly connected with the synchromesh gear, the center of the synchromesh gear is rotatably connected with the inner moving frame, the tail end of the inner moving frame is in threaded connection with the screw, the screw is rotatably connected with the crankcase, and the inner moving frame is horizontally and slidably connected with the crankcase. The balance flywheel rotating in the reverse direction counteracts vibration generated by movement of the crankshaft part and the piston, vibration generated during operation is reduced, noise can be effectively reduced, use is more silent, and the problems that a person holds the chain saw by hand and is prone to being affected by vibration, and the noise generated by an engine can be increased by the vibration are solved.

Description

Technical Field

[0001] The utility model relates to the technical field of chain saw engines, in particular to a small silent engine for a chain saw. Background Art

[0002] The chain saw uses a small single-cylinder engine as its power source. The small single-cylinder engine drives the chain of the chain saw to rotate. The engine-type chain saw has a longer battery life and better portability, and is more suitable for use in the field.

[0003] The small engine used in the chain saw is a single-piston single-cylinder engine. The single-piston single-cylinder engine will produce large vibrations during operation. The vibration of the single-cylinder engine will also be transmitted to the chain saw bracket. People holding the chain saw need to overcome the influence of vibration. The vibration will increase the noise generated by the engine. The friction between the vibrating engine and the chain saw bracket is also likely to generate noise. Summary of the invention

[0004] The disclosed embodiment relates to a small silent engine for a chainsaw. A balancing flywheel rotates in the opposite direction synchronously with a crankshaft. The counter-rotating balancing flywheel offsets the vibrations generated by the crankshaft and the piston movement, thereby reducing the vibrations generated during operation and effectively reducing noise. The engine is more silent when used and reduces the vibration of the chainsaw on the chainsaw. Less vibration makes it easier for people to hold the saw and reduces the noise generated by the friction between the vibrating engine cylinder and the chainsaw bracket.

[0005] In a first aspect of the present disclosure, a small silent engine for a chain saw is provided, which specifically comprises: an engine block, a crankcase and a balancing flywheel, wherein the crankcase is fixed to the rear end of the engine block with bolts, a balancing flywheel is arranged in the middle of the crankcase, buffer rubber blocks are arranged at the upper and lower ends of the head end of the engine block, a piston is slidably arranged inside the engine block, the tail end of the piston is rotatably connected to a connecting rod, the tail end of the connecting rod is rotatably connected to the middle part of a crankshaft, side connecting gears are fixed on both sides of the crankshaft, the head end of the engine block is also provided with spark plugs, fuel injectors and other components that are the same as those of existing engines, and the sides of the engine block are provided with intake and exhaust pipes with the same structure as those of existing engines.

[0006] In at least some embodiments, a side cover plate is bolted to the outer side of the crankcase, and the crankcase and the crankshaft bearing are rotatably connected.

[0007] In at least some embodiments, the crankcase surrounds the outside of the crankshaft above and below, and the inside of the crankcase is connected to the engine cylinder block.

[0008] In at least some embodiments, the center of the balancing flywheel is fixedly connected to the synchronous gear, the center of the synchronous gear is rotatably connected to the inner moving frame, and the tail end of the inner moving frame is threadedly connected to the screw rod.

[0009] In at least some embodiments, the screw rod is rotationally connected to the crankcase, the inner movable frame is horizontally slidingly connected to the crankcase, the balancing flywheel and the synchronous gear are located in a cavity between the crankcase and the side cover plate, the screw thread guides the inner movable frame to move axially, the inner movable frame and the synchronous gear and the balancing flywheel move synchronously, and the synchronous gear is away from the side connecting gear.

[0010] In at least some embodiments, the synchronous gear is meshed with the side connecting gear, the synchronous gear and the crankshaft rotate in opposite directions, the synchronous gear and the balance flywheel rotate synchronously, and the balance flywheel rotating in opposite directions offsets the vibration of the crankshaft and the piston.

[0011] In at least some embodiments, a first connecting tube is fixed to the front end of the buffer rubber block, a tail connecting column is fixed to the rear end of the buffer rubber block, the first connecting tube and the first connecting bolt are fixedly connected, the tail connecting column and the tail connecting bolt are fixedly connected, the inner diameter of the first connecting tube is larger than the outer diameter of the tail connecting column, the first connecting bolt is connected to the screw hole of the engine cylinder body, and the buffering of the buffer rubber block reduces the transmission of the vibration of the engine cylinder body to the chain saw bracket.

[0012] The utility model provides a small silent engine for a chain saw, which has the following beneficial effects:

[0013] The balancing flywheel rotates in the opposite direction synchronously with the crankshaft. The counter-rotating balancing flywheel offsets the vibration generated by the crankshaft and piston movement. Reducing the vibration generated during operation can also effectively reduce noise, making it quieter to use and reducing the vibration of the engine on the chain saw. Less vibration makes it easier for people to hold.

[0014] The buffer rubber block is located between the engine block and the chain saw bracket. The buffer rubber block buffers the engine block and reduces the transmission of the engine block vibration to the chain saw bracket. The person holding the chain saw bracket is more stable and the noise generated by the friction between the vibrating engine block and the chain saw bracket is also reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solution of the embodiment of the utility model, the drawings of the embodiment will be briefly introduced below.

[0016] The drawings described below only relate to some embodiments of the present invention, but are not intended to limit the present invention.

[0017] In the attached picture:

[0018] Figure 1 A schematic diagram of a half-section structure of an engine cylinder block of the present application is shown;

[0019] Figure 2 A schematic diagram of the structure of a half-section of a crankcase of the present application is shown;

[0020] Figure 3A schematic structural diagram of a cross section of a buffer rubber block of the present application is shown;

[0021] Figure 4 A schematic diagram showing the position structure of the balance flywheel of the present application is shown;

[0022] Figure 5 The structural schematic diagram of the balance flywheel of the present application is shown;

[0023] Figure 6 A schematic structural diagram showing a synchronous gear in the present application in a state of being connected to a gear on the far side;

[0024] Figure 7 A schematic structural diagram of a cross section of the inner mobile frame of the present application is shown;

[0025] Reference numerals list

[0026] 1. Engine cylinder block; 101. Piston; 102. Connecting rod; 103. Crankshaft; 104. Side connecting gear;

[0027] 2. Crankcase; 201. Side cover;

[0028] 3. Balance flywheel; 301. Synchronous gear; 302. Inner moving frame; 303. Screw;

[0029] 4. Buffer rubber block; 401. First connecting bolt; 402. Rear connecting bolt; 403. First connecting pipe; 404. Rear connecting column. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution of the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings of the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all of the embodiments. Based on the described embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0031] Example 1: Please refer to Figures 1 to 7 :

[0032] The utility model proposes a small silent engine for a chain saw, comprising: an engine cylinder block 1, a crankcase 2 and a balance flywheel 3, a piston 101 is slidably arranged inside the engine cylinder block 1, the tail end of the piston 101 is rotatably connected to a connecting rod 102, the tail end of the connecting rod 102 is rotatably connected to the middle of a crankshaft 103, side connecting gears 104 are fixed on both sides of the crankshaft 103, a spark plug, a fuel injection nozzle and other components identical to those of an existing engine are also arranged at the head end of the engine cylinder block 1, an air intake and exhaust pipe having the same structure as that of an existing engine are arranged on the side of the engine cylinder block 1, a crankcase 2 is bolted to the tail end of the engine cylinder block 1, a side cover plate 201 is bolted to the outer side of the crankcase 2, the crankcase 2 is rotatably connected to the crankshaft 103 bearing, the crankcase 2 is surrounded by the outer side of the crankshaft 103 from top to bottom, and the inner side of the crankcase 2 is communicated with the engine cylinder block 1, A balancing flywheel 3 is arranged in the middle of the crankcase 2, the center of the balancing flywheel 3 is fixedly connected to the synchronous gear 301, the center of the synchronous gear 301 is rotatably connected to the inner movable frame 302, the tail end of the inner movable frame 302 is screwed to the screw 303, the screw 303 is rotatably connected to the crankcase 2, the inner movable frame 302 is horizontally slidably connected to the crankcase 2, the balancing flywheel 3 and the synchronous gear 301 are in the cavity between the crankcase 2 and the side cover plate 201, the thread of the screw 303 guides the inner movable frame 302 to move axially, the inner movable frame 302 and the synchronous gear 301 and the balancing flywheel 3 move synchronously, the synchronous gear 301 is away from the side connecting gear 104, the side connecting gear 104 and the synchronous gear 301 are no longer meshed and rotate synchronously, so as to realize the switching of the balancing flywheel 3 between the rotating mode and the non-rotating mode, and the head end of the engine cylinder body 1 is provided with a buffer rubber block 4 at the upper and lower ends.

[0033] In the disclosed embodiment, the synchronous gear 301 and the side connecting gear 104 are meshed, the synchronous gear 301 and the crankshaft 103 rotate in opposite directions, and the synchronous gear 301 and the balancing flywheel 3 rotate synchronously. The balancing flywheel 3 rotating in the opposite direction offsets the vibration generated by the movement of the crankshaft 103 and the piston 101, thereby reducing the vibration generated during operation and effectively reducing noise, making it quieter to use.

[0034] In the disclosed embodiment, the buffer rubber block 4 is made of rubber material, a first connecting pipe 403 is fixed to the head end of the buffer rubber block 4, a tail connecting column 404 is fixed to the tail end of the buffer rubber block 4, the first connecting pipe 403 is fixedly connected to the first connecting bolt 401, the tail connecting column 404 is fixedly connected to the tail connecting bolt 402, the inner diameter of the first connecting pipe 403 is larger than the outer diameter of the tail connecting column 404, the first connecting bolt 401 is connected to the screw hole of the engine cylinder body 1, the buffering of the buffer rubber block 4 reduces the transmission of the vibration of the engine cylinder body 1 to the chain saw bracket, the person holding the chain saw bracket is more stable to use, and the noise generated by the friction between the vibrating engine cylinder body 1 and the chain saw bracket is also reduced.

[0035] Embodiment 2, on the basis of embodiment 1, the inner movable frame 302 and the screw rod 303 are not provided, and the balancing flywheel 3 continues to rotate with the crankshaft 103, thereby reducing the number of components and the difficulty of production and installation, or the inner movable frame 302 is driven to move by a motor to realize automatic adjustment of the rotation state of the two balancing flywheels 3 and the head of the crankshaft 103 at a high and low speed, and both balancing flywheels 3 rotate at a low speed, thereby reducing the vibration at a low speed.

[0036] The working principle of this embodiment is as follows: the piston 101 reciprocates back and forth in the combustion chamber of the engine cylinder 1, and the piston 101 drives the crankshaft 103 to reciprocate through the connecting rod 102. The circular shafts on both sides of the crankshaft 103 can provide power for the chain saw, and the crankshaft 103 and the side connecting gear 104 rotate synchronously. The side connecting gear 104 engages and drives the synchronous gear 301 to rotate synchronously. The synchronous gear 301 and the balance flywheel 3 rotate synchronously, and the balance flywheel 3 rotates synchronously in the opposite direction with the crankshaft 103. The counter-rotating balance flywheel 3 offsets the vibration generated by the movement of the crankshaft 103 and the piston 101, reducing the vibration generated during operation can also effectively reduce noise, making it quieter to use and reducing the vibration of the engine on the chain saw. Less vibration is more convenient for personnel's hands By rotating the screw rod 303, the thread of the screw rod 303 guides the inner moving frame 302 to move axially, and the inner moving frame 302, the synchronous gear 301 and the balancing flywheel 3 move synchronously, and the synchronous gear 301 is away from the side connecting gear 104, and the side connecting gear 104 and the synchronous gear 301 are no longer meshed and rotate synchronously, so that the balancing flywheel 3 can be adjusted to the rotation and non-rotation modes. One of the two balancing flywheels 3 can rotate while the other does not rotate, and the rotation speed of the crankshaft 103 can be adjusted. The crankshaft 103 is mostly used at a high speed, and the high speed has relatively small vibration. Only one balancing flywheel 3 can be rotated. The two balancing flywheels 3 are arranged separately, so that the space where the middle crankshaft 103 is located is avoided from being squeezed by the synchronous rotation of the balancing flywheel 3, thereby ensuring the miniaturization of the overall engine;

[0037] The two first connecting bolts 401 are respectively screwed and fixed to the two threaded holes at the upper and lower ends of the engine cylinder body 1, and the tail connecting bolt 402 is connected and fixed to the nut of the chain saw bracket. The buffer rubber block 4 is between the engine cylinder body 1 and the chain saw bracket. The vibration of the engine cylinder body 1 will squeeze the buffer rubber block 4, and the buffer rubber block 4 buffers the engine cylinder body 1. The buffering of the buffer rubber block 4 reduces the transmission of the vibration of the engine cylinder body 1 to the chain saw bracket. The person holding the chain saw bracket is more stable to use, and the noise generated by the friction between the vibrating engine cylinder body 1 and the chain saw bracket, or the noise generated by the vibration of the chain saw bracket driven by the engine cylinder body 1 is reduced, so it is quieter to use. The space between the first connecting pipe 403 and the tail connecting column 404 can also be moved in the circumferential direction to achieve vibration buffering in the vertical direction of the circumference, thereby improving the person's chain saw usage experience.

[0038] In this article, there are a few points to note:

[0039] 1. The drawings of the embodiments of the present disclosure only involve structures related to the embodiments of the present disclosure, and other structures may refer to general designs.

[0040] 2. In the absence of conflict, the embodiments of the present disclosure and the features therein may be combined with each other to obtain new embodiments.

[0041] The above are only specific embodiments of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present disclosure, which should be included in the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be based on the protection scope of the claims.

Claims

1. A small silent engine for a chain saw, comprising: An engine cylinder block (1), a crankcase (2) and a balancing flywheel (3); the characteristics are that a crankcase (2) is fixed to the rear of the engine cylinder block (1), a balancing flywheel (3) is arranged in the middle of the crankcase (2), buffer rubber blocks (4) are arranged at the top and bottom of the head end of the engine cylinder block (1), the center of the balancing flywheel (3) is fixedly connected to a synchronous gear (301), the center of the synchronous gear (301) is rotatably connected to an inner movable frame (302), and the rear end of the inner movable frame (302) is screwed to a screw rod (303).

2. A small silent engine for a chain saw according to claim 1, characterized in that: A piston (101) is slidably disposed inside the engine cylinder (1); the rear end of the piston (101) is rotatably connected to a connecting rod (102); the rear end of the connecting rod (102) is rotatably connected to the middle of a crankshaft (103); and side connecting gears (104) are fixed to both sides of the crankshaft (103).

3. A small silent engine for a chain saw according to claim 1, characterized in that: A side cover plate (201) is fixed to the outer side of the crankcase (2) by bolts, and the crankcase (2) and the crankshaft member (103) are rotatably connected.

4. A small silent engine for a chain saw according to claim 1, characterized in that: The crankcase (2) surrounds the outside of the crankshaft (103) from top to bottom, and the inside of the crankcase (2) is connected to the engine cylinder block (1).

5. A small silent engine for a chain saw according to claim 1, characterized in that: The screw rod (303) is rotationally connected to the crankcase (2), the inner movable frame (302) is horizontally slidably connected to the crankcase (2), and the balance flywheel (3) and the synchronous gear (301) are located in a cavity between the crankcase (2) and the side cover plate (201).

6. A small silent engine for a chain saw according to claim 3, characterized in that: The synchronous gear (301) is meshed with the side connecting gear (104), and the synchronous gear (301) and the crankshaft (103) rotate in opposite directions.

7. A small silent engine for a chain saw according to claim 6, characterized in that: A first connecting pipe (403) is fixed to the head end of the buffer rubber block (4), and a tail connecting column (404) is fixed to the tail end of the buffer rubber block (4); the first connecting pipe (403) and the first connecting bolt (401) are fixedly connected, and the tail connecting column (404) and the tail connecting bolt (402) are fixedly connected; the inner diameter of the first connecting pipe (403) is greater than the outer diameter of the tail connecting column (404), and the first connecting bolt (401) is connected to a screw hole of the engine cylinder body (1).

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