Engine crankshaft convenient for local replacement

Abstract

The utility model relates to the technical field of engine crankshafts, in particular to an engine crankshaft convenient for partial replacement, which comprises a crankshaft body and a fixing component arranged at the front end of the crankshaft body. The crankshaft body comprises a front end shaft; the fixing assembly comprises a connecting shaft and a shaft cover; the shaft cover is fixedly arranged, and the connecting shaft is arranged between the shaft cover and the front end shaft; the connecting shaft is connected with the shaft cover and the crankshaft body in an inserted mode, the outer diameter of the connecting shaft is smaller than the outer diameter of the shaft cover and the outer diameter of the front end shaft, and the coaxiality of the gear and the crankshaft can be improved so that normal operation of an engine can be guaranteed.

Description

Technical Field

[0001] The utility model relates to the technical field of engine crankshafts, and specifically relates to an engine crankshaft which is convenient for partial replacement. Background Art

[0002] The crankshaft is composed of the main journal, connecting rod journal crank arm, balance block, front axle end and rear axle end. The crankshaft is the main rotating part of the engine. After the connecting rod is installed, it can take over the up and down movement of the connecting rod and convert it into a circular motion. It is an important part of the engine. At present, the crankshaft connecting rod is fixed to the crankshaft by bolts. The crankshaft is subjected to the combined action of the centrifugal force of the rotating mass, the periodically changing gas inertia force and the reciprocating inertia force, so that the crankshaft is subjected to bending and torsional loads.

[0003] After long-term use, the gear at one end of the engine crankshaft on the market will age and need to be disassembled and replaced. Most crankshafts and gears are connected with interference fits and keys or retaining springs, which makes it inconvenient to disassemble and replace the gears and crankshaft rods. Based on this prior art, a Chinese patent for a forged steel crankshaft with a publication number of CN219932704U achieves the purpose of convenient replacement by detachably arranging gears between a support shaft and a connecting shaft. However, the disadvantage of this patent is that the gears are fixed by multiple bolts. As the crankshaft is used, the bolts will loosen, reducing the coaxiality between the gear and the output shaft end of the crankshaft. Because the crankshaft is a high-speed rotating part, the reduced coaxiality will inevitably intensify the vibration of the crankshaft, affecting the normal operation of the engine. Utility Model Content

[0004] In view of the deficiencies in the prior art, the purpose of the utility model is to provide an engine crankshaft that is easy to partially replace, which can improve the coaxiality of the gear and the crankshaft to ensure the normal operation of the engine.

[0005] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: an engine crankshaft that is easy to partially replace, comprising a crankshaft body and a fixing assembly arranged at the front end of the crankshaft body; the crankshaft body comprises a front end shaft; the fixing assembly comprises a connecting shaft and a shaft cover; the shaft cover is fixedly arranged, and the connecting shaft is arranged between the shaft cover and the front end shaft; the connecting shaft is plug-in connected to the shaft cover and the crankshaft body, and the outer diameter of the connecting shaft is smaller than the outer diameter of the shaft cover and the front end shaft.

[0006] Preferably, a key is provided on the outer circumference of the connecting shaft; and a keyway adapted to the key is provided at the rear end of the shaft cover and the front end of the front shaft.

[0007] Preferably, the key is composed of a plurality of fixing blocks, and the plurality of fixing blocks are evenly distributed around the axis of the connecting shaft.

[0008] Preferably, the bond is a cross structure.

[0009] Preferably, the fixing assembly further comprises bolts; the bolts penetrate the shaft cover and the connecting shaft in sequence from front to back to be fixedly connected to the front end shaft.

[0010] Preferably, the shaft cover and the connecting shaft are both slidably connected to the bolts.

[0011] Preferably, a countersunk hole is also formed at the front end of the shaft cover.

[0012] Preferably, it also includes a plurality of fastening screws; a cover hole is opened on the shaft cover; a shaft hole is opened on the front end shaft; and the fastening screws are crimped with the bolts through the cover hole and the shaft hole.

[0013] Preferably, the outer diameter of the shaft cover is the same as the outer diameter of the front end shaft.

[0014] Preferably, the crankshaft body further comprises a crank; and a weight-reducing groove is provided on the crank.

[0015] Compared with the prior art, the beneficial effect of the utility model is that a connecting shaft, a shaft cover and a bolt for fixing the gear are arranged at the front end of the crankshaft body. When in use, the gear is sleeved on the connecting shaft and is pressed and fixed between the shaft cover and the front end shaft to avoid axial movement of the gear. In this way, the purpose of convenient replacement of the gear can be achieved, and the crankshaft body, the fixing assembly and the gear can always be coaxial. Compared with the prior art, the factors causing deflection vibration are reduced, thereby ensuring the normal operation of the engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic structural diagram of the first embodiment of the present utility model;

[0017] Figure 2 This is a schematic diagram of the front end shaft structure of the utility model;

[0018] Figure 3 It is a schematic diagram of the axial section of the front end shaft and the fixing assembly of the utility model;

[0019] Figure 4 This is a schematic diagram of the connecting shaft structure of the utility model;

[0020] Figure 5 This is a schematic diagram of the shaft cover structure of the utility model.

[0021] In the figure: 1 crankshaft body, 11 front end shaft, 12 rear end shaft, 13 main journal, 14 connecting rod journal, 15 crank, 111 shaft groove, 112 first keyway, 113 connecting hole, 114 shaft hole;

[0022] 2 fixing assembly, 21 connecting shaft, 22 shaft cover, 23 bolt, 211 key, 212 through hole, 221 cover groove, 222 second key groove, 223 countersunk hole, 224 cover hole. DETAILED DESCRIPTION

[0023] The following describes the specific implementation of the utility model in detail in conjunction with the accompanying drawings so that those skilled in the art can more clearly understand how to practice the utility model. Although the utility model is described in conjunction with its preferred specific embodiments, these embodiments are only illustrative, rather than limiting the scope of the utility model.

[0024] Specific embodiment 1: Please refer to Figure 1-5 An engine crankshaft that is easy to partially replace includes: a crankshaft body 1 and a fixing component 2 arranged at the front end of the crankshaft body 1, the fixing component 2 and the front end of the crankshaft body 1 are detachably connected, when in use, the gear is coaxially installed with the crankshaft body 1 through the fixing component 2, and this arrangement can make the disassembly and replacement between the gear and the body 1 more convenient.

[0025] Specifically, the crankshaft body 1 is composed of a front end shaft 11 arranged on the front side, a rear end shaft 12 arranged on the rear side, and a main journal 13, a connecting rod journal 14 and a crank 15 arranged in the middle, and the fixing component 2 is fixedly connected to the front end shaft 11; an axis groove 111 is opened at the axis center of the front end of the front end shaft 11, and a first key groove 112 of a cross structure is opened on the side wall of the axis groove 111, and a connecting hole 113 is opened on the bottom wall of the axis groove 111, and an internal thread is opened on the inner side of the connecting hole 113; the connecting hole 113 is a blind hole; the outer periphery of the front end shaft 11 is also opened with an axis groove 111 connected to the connecting hole 113.

[0026] In one embodiment, in order to reduce dead weight, a weight-reducing groove is provided on the crank 15 .

[0027] The fixing assembly 2 includes a connecting shaft 21 , a shaft cover 22 and bolts 23 .

[0028] See also Figure 4 The connecting shaft 21 is a tubular structure with a through hole 212 at the axis, and a cross-shaped key 211 matching the first key groove 112 is provided on the outer periphery of the connecting shaft 21;

[0029] The shaft cover 22 is a tubular structure, and a cover groove 221 is provided at the axis center of the rear end thereof, and a second key groove 222 adapted to the key 211 is provided on the inner side wall of the cover groove 221; a countersunk hole 223 is provided at the front end of the shaft cover 22, and the inner diameters of the cover groove 221 and the countersunk hole 223 are both larger than the inner diameter of the shaft cover 22;

[0030] The outer periphery of the shaft cover 22 is also provided with a cover hole 224 communicating with the inner side of the shaft cover 2 body;

[0031] The outer diameter of the connecting shaft 21 is matched with the inner diameters of the shaft groove 111 and the cover groove 221 .

[0032] See also Figure 2 The bolt 23 passes through the shaft cover 22 and the connecting shaft 21 from front to back and is connected and fixed to the front end shaft 11, wherein the shaft cover 22 and the connecting shaft 21 are both slidably connected to the screw rod of the bolt 23, and the screw rod of the bolt 23 is at least partially embedded in the connecting hole 113 and is threadedly connected to the front end shaft 11, and the head of the bolt 23 is arranged in the countersunk hole 223; further, when in use, the gear sleeve is arranged on the connecting shaft 21 and is pressed and fixed between the shaft cover 22 and the front end shaft 11 to avoid axial movement of the gear. In addition, in order to make the gear adapt to the crankshaft, a keyway compatible with the key 211 should also be opened at the axis center of the gear; in this way, the purpose of convenient replacement of the gear can be achieved, and the crankshaft body 1, the fixing assembly 2 and the gear can always be coaxial, which reduces the factors causing deflection vibration compared with the prior art and ensures the normal operation of the engine.

[0033] In addition, the crankshaft also includes a plurality of fastening screws. After assembly, the fastening screws are arranged in the shaft hole and the cover hole and are crimped with the bolt 23 to make the bolt 23 more fixed and avoid axial displacement of the bolt 23.

[0034] In one embodiment, the shapes of the first keyway and the second keyway are adapted to the shape of the key 211 . In addition, in order to ensure the coaxiality of the structure, the first keyway or the second keyway needs to be arranged in a symmetrical structure around the axis of the front end shaft 11 .

[0035] In this embodiment, in order to maintain the smoothness of the structure, the outer diameter of the shaft cover 22 is the same as the outer diameter of the front end shaft 11 .

[0036] In addition, it should be noted that, in order to adapt to gears of different specifications, the lengths of the connecting shaft 21 and the bolts 23 can be adjusted according to the size of the gears to expand the application range of the crankshaft.

[0037] Through the technical solution, a connecting shaft, a shaft cover and a bolt for fixing the gear are arranged at the front end of the crankshaft body. When in use, the gear is sleeved on the connecting shaft and is pressed and fixed between the shaft cover and the front end shaft to avoid axial movement of the gear. In this way, the purpose of convenient replacement of the gear can be achieved, and the crankshaft body, the fixing assembly and the gear can always be coaxial. Compared with the prior art, the factors causing deflection vibration are reduced, thereby ensuring the normal operation of the engine.

[0038] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An engine crankshaft that is easy to partially replace, characterized in that: The invention comprises a crankshaft body (1) and a fixing assembly (2) arranged at the front end of the crankshaft body (1); the crankshaft body (1) comprises a front end shaft (11); the fixing assembly (2) comprises a connecting shaft (21) and a shaft cover (22); the shaft cover (22) is fixedly arranged, and the connecting shaft (21) is arranged between the shaft cover (22) and the front end shaft (11); the connecting shaft (21) is plug-connected with the shaft cover (22) and the crankshaft body (1), and the outer diameter of the connecting shaft (21) is smaller than the outer diameters of the shaft cover (22) and the front end shaft (11).

2. An engine crankshaft that is easy to partially replace according to claim 1, characterized in that: The outer periphery of the connecting shaft (21) is provided with a key (211); the rear end of the shaft cover (22) and the front end of the front shaft (11) are both provided with a key slot adapted to the key (211).

3. An engine crankshaft that is easy to partially replace according to claim 2, characterized in that: The key (211) is composed of a plurality of fixed blocks, and the plurality of fixed blocks are evenly distributed around the axis of the connecting shaft (21).

4. The engine crankshaft that is easy to partially replace according to claim 3, characterized in that: The key (211) is a cross structure.

5. The engine crankshaft that is easy to partially replace according to claim 1, characterized in that: The fixing assembly (2) further comprises a bolt (23); the bolt (23) passes through the shaft cover (22) and the connecting shaft (21) in sequence from front to back and is fixedly connected to the front end shaft (11).

6. The engine crankshaft that is easy to partially replace according to claim 5, characterized in that: The shaft cover (22) and the connecting shaft (21) are both slidably connected to the bolt (23).

7. The engine crankshaft that is easy to partially replace according to claim 5, characterized in that: The front end of the shaft cover (22) is also provided with a countersunk hole.

8. The engine crankshaft that is easy to partially replace according to claim 5, characterized in that: It also includes a plurality of fastening screws; the shaft cover (22) is provided with a cover hole; the front end shaft (11) is provided with an axis hole; the fastening screws are press-fitted with the bolts (23) through the cover hole and the axis hole.

9. The engine crankshaft that is easy to partially replace according to claim 1, characterized in that: The outer diameter of the shaft cover (22) is the same as the outer diameter of the front end shaft (11).

10. The engine crankshaft that is easy to partially replace according to claim 1, characterized in that: The crankshaft body (1) also includes a crank; and a weight-reducing groove is provided on the crank.

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