Installation structure of engine chain limiter

Abstract

The present invention provides an installation structure of an engine chain limit frame, which belongs to the field of engine technology. It solves the problem of poor installation stability of the existing limit frame. The engine includes a crankcase and a crankshaft arranged in the crankcase, and the installation structure includes bolts, elastic members and limit pins inserted in the crankcase. The limit frame is fixed in the crankcase by bolts, and the installation structure also includes one end of the elastic member pressing on the limit pin so that the limit pin is partially embedded in the crankshaft, and the other end of the elastic member abuts against the limit frame. The elastic member and the head of the bolt are respectively located on both sides of the limit frame, and the direction of the elastic force of the elastic member and the length direction of the bolt are both arranged along the axial direction of the crankshaft. The installation structure of the limit frame has the advantages of axially positioning the crankshaft while preventing the bolts from loosening.

Description

Technical Field

[0001] The invention belongs to the technical field of engines and relates to a mounting structure of an engine chain limiting frame. Background Art

[0002] The existing automobile timing system usually drives the engine's valve train through a timing chain, which is commonly known as a chain drive. Chain drives have significant advantages such as compact structure, high power transmission, high reliability and wear resistance, diverse design types, low maintenance, and long service life. However, when a chain drive is used, when the timing chain is loose, the crankshaft end of the timing chain will fall downward due to gravity, which can easily cause the crankshaft end of the chain to run out of gear, resulting in timing errors.

[0003] In response to the above problems, people have made various improvements, and some have even applied for patents. For example, Chinese patent literature discloses an engine timing chain anti-derailment device [patent number: 201120480014.X; authorization announcement number: CN202391505U], which includes a limit block arranged under the timing chain and capable of limiting the downward movement of the timing chain, and the limit block is fixed on the engine main bearing cover.

[0004] In the anti-chain-off device of this structure, the limit block is fixed to the main bearing cover of the engine by a bolt. However, cars, motorcycles and other vehicles are subject to bumps during driving. Long-term bumps can cause the bolts to loosen. Once the bolts are loose, the limit block will rotate or fall off. The rotating or falling limit block will abut against the chain, making it impossible for the chain to rotate normally, causing the car or motorcycle to malfunction. At the same time, during driving, the crankshaft of cars and motorcycles has the problem of axial movement, which accelerates the abnormal wear of the crankshaft and bearings, pistons and cylinders, and reduces the service life. Summary of the invention

[0005] The purpose of the present invention is to address the above-mentioned problems existing in the prior art and to propose an installation structure for an engine chain limiter, the technical problem to be solved is how to achieve axial positioning of the crankshaft while preventing the bolts from loosening.

[0006] The objective of the present invention can be achieved through the following technical solutions: an installation structure of an engine chain limit frame, the engine includes a crankcase and a crankshaft arranged in the crankcase, the installation structure includes bolts, and the limit frame is fixedly connected to the crankcase by bolts, and is characterized in that the installation structure also includes an elastic member and a limit pin passing through the crankcase, one end of the elastic member is pressed on the limit pin so that the limit pin is partially embedded in the crankshaft, and the other end of the elastic member is against the limit frame, the elastic member and the head of the bolt are respectively located on both sides of the limit frame, and the direction of the elastic force of the elastic member and the length direction of the bolt are both arranged along the axial direction of the crankshaft.

[0007] The limit frame can limit the downward movement of the crankshaft end of the timing chain to prevent the chain from falling off. The limit frame is fixed by bolts, and there is a spacing between the threads of the bolts. After the bolts are fixed to the crankcase, there is a small gap. The bolts and the crankcase can move slightly relative to each other in the axial direction, and this small movement has the risk of causing the bolts to fall off under the action of long-term bumps. Under the action of the elastic force of the elastic member, the limit pin is embedded in the crankshaft to axially compress the crankshaft to prevent the crankshaft from axially moving. At the same time, under the action of the elastic force of the elastic member, the elastic member provides a reverse force to the limit frame. Since the elastic member and the head of the bolt are respectively located on both sides of the limit frame, the limit frame can transmit the force to the head of the bolt, so that the bolt moves slightly axially under the action of the force, so as to eliminate the small gap between the bolt and the crankcase, solve the problem of loose bolts, and enable the limit frame to be better fixed to the crankcase, thereby improving the stability of the limit frame and preventing the limit frame from rotating and falling off. By arranging the limit pin and the elastic member, the axial compression of the crankshaft is achieved to prevent the axial movement of the crankshaft, and at the same time the problem of bolt loosening is solved, and the stability of the limit frame is improved. It has a dual effect and a compact structure.

[0008] In the above-mentioned mounting structure of an engine chain limit frame, the crankcase has a mounting block with a protruding arrangement, the mounting block has a fixing hole for bolts to penetrate and a limiting hole for installing a limiting pin, the limiting hole and the fixing hole are arranged adjacent to each other, and the limiting frame is tightly fitted with the mounting block through bolts. The installation of the mounting block provides an installation position, and the tight fit between the limiting frame and the mounting block improves the stability of the limiting frame. At the same time, the limiting hole in the mounting block provides a moving path for the limiting pin and prevents the limiting pin and the elastic member from falling off.

[0009] In the above-mentioned installation structure of the engine chain limit frame, the outer wall of the limit pin fits with the inner wall of the limit hole, and the end of the installation block that abuts against the limit frame has a plurality of concave air-permeable grooves, which connect the limit hole with the outside. The outer wall of the limit pin fits with the inner wall of the limit hole, which improves the stability and movement accuracy of the limit pin; the setting of the air-permeable groove plays a role in ventilation, so that the air pressure in the limit hole is the same as the air pressure in the outside world, preventing the limit pin from moving abnormally due to the abnormal air pressure in the limit hole, and improving stability.

[0010] In the above-mentioned installation structure of the engine chain limit frame, the crankcase also has a protruding positioning pin, the positioning pin is arranged adjacent to the mounting block, the positioning pin is fixedly connected to the mounting block through the first connecting rib, the limit frame has a positioning hole, and the positioning pin is partially embedded in the positioning hole. The setting of the positioning pin and the positioning hole further improves the stability of the limit frame, so that the limit frame does not have problems such as rotation; the setting of the first connecting rib connects the positioning pin and the mounting frame into one, improves the strength of the positioning pin and the mounting frame, thereby improving the installation firmness of the limit frame, improving the stability of the limit frame, and preventing the limit frame from rotating and falling off.

[0011] In the above-mentioned mounting structure of the engine chain limiter, the crankcase has a protruding mounting ring, the mounting block is located inside the mounting ring, and the mounting block is fixedly connected to the mounting ring via a second connecting rib. The second connecting rib further improves the firmness of the mounting frame, thereby improving the stability of the limiter and preventing the limiter from rotating and falling off.

[0012] In the above-mentioned engine chain limiter mounting structure, the crankcase, mounting block, positioning pin, first connecting rib, mounting ring and second connecting rib are an integrated structure. The integrated structure has good firmness and high stability, and is easy to manufacture and reduce costs.

[0013] In the above-mentioned installation structure of the engine chain limit frame, the limit frame includes an arc-shaped limit plate and a flat fixed plate, the limit plate and the fixed plate are an integrated structure, the limit plate is perpendicular to the fixed plate and the connection between the limit plate and the fixed plate is smoothly transitioned, and the elastic member acts on the fixed plate. This structure makes the limit frame highly firm and stable.

[0014] In the above-mentioned installation structure of the engine chain limit frame, the limit plate is located at one end of the fixed plate, and the end of the fixed plate is also provided with a weight-reducing hole, and the other end of the fixed plate has a protruding abutting portion for the elastic member to abut, and the abutting portion and the limit plate are located on the same side of the fixed plate, and the bolt is passed through the middle of the fixed plate and is located between the abutting portion and the weight-reducing hole. This structure balances the weight of the limit frames on both sides of the bolt, further improves the installation stability of the limit frame, and prevents the limit frame from rotating and falling off.

[0015] In the above-mentioned engine chain limiter mounting structure, a recessed clearance gap is provided between the abutment portion and the limiter plate, and the bottom of the clearance gap extends to the connection between the limiter plate and the fixing plate, so that the limiter can be easily processed and there is no problem of breakage at the connection.

[0016] In the above-mentioned engine chain limiter mounting structure, the outer side wall of the abutment portion is arc-shaped, so as to reasonably utilize the space, prevent the abutment portion from contacting the outside, and at the same time, it is not easy to cut the user compared with angular parts.

[0017] In the above-mentioned installation structure of the engine chain limit frame, the elastic member is a cylindrical spring or a conical spring, the limit pin has a concave limit blind hole, one end of the elastic member is located in the limit blind hole and acts on the limit pin, and the other end of the elastic member acts on the limit frame. The limit blind hole serves to limit the elastic member, preventing the elastic member from deviating from the set direction, and at the same time, the elastic member provides elastic force in the set direction, achieving the dual effects of axially pressing the crankshaft to prevent the crankshaft from axially moving and solving the problem of bolt loosening to improve the stability of the limit frame.

[0018] Compared with the prior art, the installation structure of an engine chain limiter provided by the present invention has the following advantages:

[0019] 1. This limiter can limit the downward movement of the crankshaft end of the timing chain to prevent the chain from falling off and make the chain installation easier.

[0020] 2. The installation structure of the chain limit frame realizes axial compression of the crankshaft to prevent axial movement of the crankshaft by setting a limit pin and an elastic member, and at the same time solves the problem of bolt loosening and improves the stability of the limit frame, which has a dual effect and a compact structure.

[0021] 3. The weight of the limit frame on both sides of the bolt is balanced, which improves the installation stability of the limit frame and prevents the limit frame from rotating and falling off. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the overall structure of the installation structure of the engine chain limit frame.

[0023] Figure 2 It is the overall structural front view of the installation structure of the engine chain limit frame.

[0024] Figure 3 It is a sectional view of the overall structure of the installation structure of the engine chain limit frame.

[0025] Figure 4 It is a schematic diagram of the overall structure of the mounting structure mounting frame of the engine chain limit frame.

[0026] In the figure, 1. crankcase; 11. mounting ring; 2. crankshaft; 3. bolt; 31. head; 4. limit frame; 41. positioning hole; 42. limit plate; 43. fixing plate; 44. weight reduction hole; 45. abutment portion; 46. clearance gap; 5. limit pin; 51. limit blind hole; 6. elastic member; 7. mounting block; 71. limit hole; 72. fixing hole; 73. ventilation groove; 8. positioning pin; 9. first connecting rib; 10. second connecting rib; 12. chain. DETAILED DESCRIPTION

[0027] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

[0028] like Figure 1 , Figure 2 , Figure 3 As shown, the engine includes a crankcase 1 and a crankshaft 2, and the limit frame mounting structure includes a bolt 3, a limit pin 5, an elastic member 6, a mounting block 7 and a positioning pin 8.

[0029] like Figure 4 As shown, the crankcase 1 has a protruding mounting block 7, and the mounting block 7 has a limiting hole 71 and a fixing hole 72. The limiting hole 71 and the fixing hole 72 are arranged adjacent to each other, the limiting hole 71 is through, and the fixing hole 72 is a blind hole. The crankcase 1 also has a protruding positioning pin 8, which is arranged adjacent to the mounting block 7. The positioning pin 8 is fixedly connected to the mounting block 7 through a first connecting rib 9. The crankcase 1 has a protruding mounting ring 11, and the mounting block 7 is located on the inner side of the mounting ring 11, and the mounting block 7 is fixedly connected to the mounting ring 11 through a second connecting rib 10. The crankcase 1, the mounting block 7, the positioning pin 8, the first connecting rib 9, the mounting ring 11 and the second connecting rib 10 are an integrated structure.

[0030] The limit pin 5 is inserted into the limit hole 71, and the outer wall of the limit pin 5 is in contact with the inner wall of the limit hole 71. In this embodiment, the elastic member 6 is a cylindrical spring, and in actual production, the elastic member 6 is a conical spring. The limit pin 5 has a concave limit blind hole 51, one end of the elastic member 6 is located in the limit blind hole 51 and acts on the limit pin 5, and the other end of the elastic member 6 acts on the limit frame 4.

[0031] The limit frame 4 is tightly fitted with the mounting block 7 by means of bolts 3. In this embodiment, the ends of the mounting block 7 abutting against the limit frame 4 have two recessed air grooves 73, and the air grooves 73 connect the limit hole 71 with the outside. In actual production, the number of the air grooves 73 can be one or three.

[0032] The limiting frame 4 includes an arc-shaped limiting plate 42 and a flat-plate-shaped fixing plate 43. The limiting plate 42 and the fixing plate 43 are an integrated structure. The limiting plate 42 is perpendicular to the fixing plate 43 and the connection between the limiting plate 42 and the fixing plate 43 is smoothly transitioned. The limiting plate 42 is located at one end of the fixing plate 43, and the end of the fixing plate 43 is also provided with a weight-reducing hole 44. The other end of the fixing plate 43 has a protruding abutting portion 45 for the elastic member 6 to abut against. The outer wall is arc-shaped, the abutment portion 45 and the limiting plate 42 are located on the same side of the fixed plate 43, and a recessed clearance notch 46 is provided between the abutment portion 45 and the limiting plate 42. The bottom of the clearance notch 46 extends to the connection between the limiting plate 42 and the fixed plate 43. The bolt 3 is passed through the middle of the fixed plate 43 and is located between the abutment portion 45 and the weight-reducing hole 44. The fixed plate 43 is provided with a positioning hole 41, and the positioning pin 8 is partially embedded in the positioning hole 41.

[0033] During assembly, the limit pin 5 is embedded into the limit hole 71, and then the elastic member 6 is inserted into the limit blind hole 51, and the limit frame 4 is moved to make the positioning pin 8 embedded in the positioning hole 41. At this time, the elastic member 6 is against the limit frame 4, and the limit pin 5 is partially embedded in the crankshaft 2. Then the bolt 3 is inserted and tightened. Under the action of the elastic member 6, the gap between the bolt 3 and the mounting block 7 will be eliminated.

[0034] The specific embodiments described herein are merely examples of the spirit of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in similar ways, but they will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

[0035] Although the present invention uses more terms such as crankcase 1, mounting ring 11, crankshaft 2, bolt 3, head 31, limit frame 4, positioning hole 41, limit plate 42, fixing plate 43, weight reduction hole 44, abutment portion 45, clearance gap 46, limit pin 5, limit blind hole 51, elastic member 6, mounting block 7, limit hole 71, fixing hole 72, venting groove 73, positioning pin 8, first connecting rib 9, second connecting rib 10, chain 12, etc., it does not exclude the possibility of using other terms. These terms are used only to more conveniently describe and explain the essence of the present invention; interpreting them as any additional restrictions is contrary to the spirit of the present invention.

Claims

1. An engine chain limiter mounting structure, the engine comprising a crankcase (1) and a crankshaft (2) arranged in the crankcase (1), the mounting structure comprising bolts (3), the limiter (4) being fixedly connected to the crankcase (1) by the bolts (3), characterized in that The mounting structure further comprises an elastic member (6) and a limit pin (5) passing through the crankcase (1), one end of the elastic member (6) is pressed against the limit pin (5) so that the limit pin (5) is partially embedded in the crankshaft (2), the other end of the elastic member (6) is against the limit frame (4), the elastic member (6) and the head (31) of the bolt (3) are respectively located on both sides of the limit frame (4), the direction of the elastic force of the elastic member (6) and the length direction of the bolt (3) are both arranged along the axial direction of the crankshaft (2), the crankcase (1) has a protruding mounting block (7), the mounting block (7) has a fixing hole (72) for the bolt (3) to pass through and fix, and a limit hole (71) for installing the limit pin (5), the limit hole (71) and the fixing hole (72) are arranged adjacent to each other, and the limit The positioning frame (4) is tightly fitted with the mounting block (7) by means of bolts (3); the crankcase (1) is also provided with a protruding positioning pin (8); the positioning pin (8) is arranged adjacent to the mounting block (7); the positioning pin (8) is fixedly connected to the mounting block (7) by means of a first connecting rib (9); the positioning frame (4) is provided with a positioning hole (41); a portion of the positioning pin (8) is embedded in the positioning hole (41); the positioning frame (4) comprises an arc-shaped positioning plate (42) and a flat-plate-shaped fixing plate (43); the positioning plate (42) and the fixing plate (43) are an integrated structure; the positioning plate (42) and the fixing plate (43) are perpendicular to each other and the connection between the positioning plate (42) and the fixing plate (43) is smoothly transitioned; the elastic member (6) acts on the fixing plate (43).

2. The installation structure of an engine chain limiter according to claim 1, characterized in that: The outer wall of the limiting pin (5) is in contact with the inner wall of the limiting hole (71), and the end of the mounting block (7) in contact with the limiting frame (4) has a plurality of concavely arranged air-permeable grooves (73), and the air-permeable grooves (73) connect the limiting hole (71) with the outside.

3. The installation structure of an engine chain limiter according to claim 1 or 2, characterized in that: The crankcase (1) has a protruding mounting ring (11), the mounting block (7) is located inside the mounting ring (11), and the mounting block (7) is fixedly connected to the mounting ring (11) via a second connecting rib (10).

4. The installation structure of an engine chain limiter according to claim 3, characterized in that: The crankcase (1), the mounting block (7), the positioning pin (8), the first connecting rib (9), the mounting ring (11) and the second connecting rib (10) are an integrated structure.

5. The installation structure of an engine chain limiter according to claim 1 or 2, characterized in that: The limiting plate (42) is located at one end of the fixing plate (43), and the fixing plate (43) is also provided with a weight-reducing hole (44) at the end thereof. The fixing plate (43) has a protruding abutting portion (45) at the other end thereof for the elastic member (6) to abut against. The abutting portion (45) and the limiting plate (42) are located on the same side of the fixing plate (43). The bolt (3) is passed through the middle of the fixing plate (43) and is located between the abutting portion (45) and the weight-reducing hole (44).

6. The installation structure of the engine chain limiter according to claim 5, characterized in that: A recessed clearance notch (46) is provided between the abutting portion (45) and the limiting plate (42), and the bottom of the clearance notch (46) extends to the connection between the limiting plate (42) and the fixing plate (43).

7. The installation structure of an engine chain limiter according to claim 1 or 2, characterized in that: The elastic member (6) is a cylindrical spring or a conical spring, the limit pin (5) has a recessed limit blind hole (51), one end of the elastic member (6) is located in the limit blind hole (51) and acts on the limit pin (5), and the other end of the elastic member (6) acts on the limit frame (4).

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