Anti-abrasion pawl type flywheel

Abstract

The utility model discloses an anti-abrasion pawl type flywheel, and belongs to the technical field of pawl type flywheels. The utility model discloses an anti-abrasion pawl type flywheel which comprises a flywheel body, an inner core, pawls, a bearing structure and a lubricating structure. The flywheel is an annular part, and an inner ring is provided with a ratchet surface to be in meshed transmission with one end of the pawl in a transmission state; the inner core is a hollow step shaft part, a pawl installation groove is formed in the circumferential face of the middle shaft section, one end of the pawl is embedded in the pawl installation groove, and driving force from the flywheel is transmitted. An abutting swing spring is arranged below the pawl and drives the pawl to swing around the embedded end in a reciprocating mode. The flywheel is sleeved on the periphery of the middle shaft section of the inner core, and the flywheel and the inner core are coaxially and rotatably connected through a bearing structure arranged on the inner core; the lubricating structure is arranged at the pawl mounting groove and is provided with a through hole communicated with the center of the inner core so as to discharge oil to lubricate the pawl and prevent abrasion; according to the utility model, the anti-wear protection of the ratchet wheel and the pawl can be realized.

Description

Technical Field

[0001] The utility model belongs to the technical field of ratchet-type flywheels, in particular to a wear-resistant ratchet-type flywheel. Background Art

[0002] The pawl-type freewheel is a crucial transmission mechanism in a bicycle's transmission system. Through the meshing and disengagement of the ratchet and pawl, the rider can actively pedal or coast freely at any time. When coasting or riding backwards, the ratchet and pawl cannot engage, and the pawl constantly jumps to avoid the ratchet teeth, causing the bicycle to spin without transmission. This evasive movement of the pawl constantly collides and strikes the ratchet wheel and teeth, inevitably causing wear. Over time, accumulated wear on the teeth and pawl can lead to a loss of proper meshing and transmission, resulting in idling when pedaling at certain angles, or even complete loss of forward motion. Utility Model Content

[0003] The purpose of the utility model is to provide a wear-resistant pawl flywheel, which realizes wear-resistant protection for the ratchet and the pawl by designing a mechanism that automatically injects oil to lubricate the striking and colliding surfaces of the pawl and the ratchet when the pawl and the ratchet are loose and jump.

[0004] The utility model discloses an anti-wear pawl type flywheel, which comprises a flywheel, an inner core, a pawl, a bearing structure and a lubricating structure.

[0005] The flywheel is an annular part, and the inner ring is provided with a ratchet surface to engage with one end of the ratchet to transmit the power in the transmission state.

[0006] The inner core is a hollow stepped shaft component with a pawl mounting groove on the circumference of the middle shaft section. One end of the pawl is embedded in the pawl mounting groove, transmitting the driving force from the flywheel. A swing spring is installed below the pawl to drive the pawl to swing back and forth around the embedded end.

[0007] The flywheel is sleeved on the outer periphery of the middle shaft section of the inner core, and the two are connected in coaxial rotation through a bearing structure arranged on the inner core.

[0008] The lubrication structure is arranged at the pawl mounting groove and is provided with a through hole connected to the center of the inner core for discharging oil to lubricate the pawl and prevent wear.

[0009] As a further improvement of the present invention, the lubrication structure includes an oil outlet, a plunger, a compression spring, an oil filling end cap, and an oil filling spring. The inner core is provided with an oil outlet in the middle of the pawl mounting groove. The oil outlet extends obliquely into the hollow center of the inner core, with the outlet end partially penetrating to form an end surface perpendicular to the direction of the hole.

[0010] The oil outlet hole is divided into two sections with different diameters, the upper end hole diameter is smaller than the lower end hole diameter.

[0011] The plunger is a cylindrical component, divided into two sections, upper and lower. The diameter of the cylindrical upper end of the plunger is smaller than the upper diameter of the oil outlet hole, while the diameter of the cylindrical lower end of the plunger is larger than the upper end of the plunger but smaller than the lower diameter of the oil outlet hole. It is movably embedded in the oil outlet hole. The upper surface of the upper end of the plunger abuts against the swing spring, and the extrusion spring is set in the lower diameter of the oil outlet hole, with one end abutting against the lower surface of the lower end of the plunger and the other end abutting against the end surface formed by the center through-hole of the oil outlet hole. When the extrusion spring is in a compressed state, it drives the plunger upward, and the step surface of the plunger fits against the step surface at the intersection of the two sections of the oil outlet hole.

[0012] The hollow right part of the inner core is provided with a spline for disassembly and assembly, and the left part is provided with a vertically arranged oil filling end cover. The outer periphery of the oil filling end cover fits the inner wall of the inner core, and the left end face of the oil filling end cover abuts the compressed oil filling spring. Driven by the oil filling spring, the oil filling end cover as a whole tends to move to the right.

[0013] As a further improvement of the present invention, the outer periphery of the flywheel is provided with ratchet teeth for engaging the chain. Circular protrusions are provided on both sides of the flywheel from the root of the ratchet teeth, and flywheel ball grooves are provided on the inner edges of the circular protrusions on both sides.

[0014] As a further improvement to the present invention, the inner core is a hollow stepped shaft component, arranged in three steps with gradually decreasing diameters along the axial direction. The flywheel rotates outside the middle step. A core ball groove is formed on the edge of the inner core's largest diameter step, closest to the flywheel. This groove and the flywheel ball groove on the flywheel side spatially envelop each other to form an annular raceway, within which a number of steel balls are mounted.

[0015] As a further improvement of the present invention, a circular depression having a diameter larger than that of the swing spring is formed on the surface of the end where the pawl contacts the swing spring.

[0016] As a further improvement of the present invention, a lubrication hole penetrating the pawl is formed in the center of the circular depression.

[0017] As a further improvement of the present invention, when the pawl rotates around the embedded end toward the inner core side, the swing spring has a downward driving force on the plunger, driving the plunger to move toward the inner core side, and the step surface of the plunger is separated from the step surface at the junction of the two sections of the oil outlet hole, and the upper and lower sections of the oil outlet hole are connected.

[0018] As a further improvement of the present invention, an end cap is further included. The end cap is fixedly mounted on the outer side of the smallest stage end of the inner core, and has an end cap ball groove formed on the outer edge near the flywheel. The end cap ball groove and the flywheel ball groove spatially envelop each other to form an annular raceway, in which a plurality of steel balls are mounted.

[0019] As a further improvement of the present invention, after the end covers are installed, the middle hollow portion of the inner core is blocked by the end covers and the oil filling end cover respectively, forming a lubricating oil storage chamber in which lubricating oil is stored.

[0020] The utility model discloses an anti-wear pawl type flywheel. By providing a mechanism which automatically injects oil to lubricate the striking and colliding surfaces of the pawl and the ratchet wheel only when the pawl and the ratchet wheel are loose and jump, the anti-wear protection for the ratchet wheel and the pawl is achieved, which has the beneficial effect of extending the service life of the pawl type flywheel and ensuring the normal use of the bicycle. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of an overall half section of the present utility model;

[0022] Figure 2 It is an overall schematic diagram of the utility model;

[0023] Figure 3 It is a cross-sectional schematic diagram of the flywheel of the present invention taken along the vertical axis;

[0024] Figure 4 This is an enlarged schematic diagram of the lubrication structure of the utility model;

[0025] Figure 5 This is a schematic diagram of the inner core structure of the present utility model;

[0026] Figure 6 It is a cross-sectional schematic diagram of the flywheel of the present invention parallel to the axial direction;

[0027] Figure 7 It is an enlarged schematic diagram of the pawl of the present utility model;

[0028] Figure 8 This is a schematic cross-sectional view of the oil outlet of the utility model;

[0029] Figure 9 This is a schematic diagram of the end cover of the utility model;

[0030] 1. Flywheel; 2. Inner core; 3. Pawl; 4. Bearing structure; 5. Lubrication structure; 6. End cover; 101. Ratchet; 102. Ratchet surface; 103. Flywheel ball groove; 201. Pawl mounting groove; 202. Swing spring; 203. Inner core ball groove; 301. Circular depression; 302. Lubrication hole; 501. Oil outlet hole; 502. Plunger; 503. Extrusion spring; 504. Oil filling end cover; 505. Oil filling spring; 5011. End face; 5021. Upper end of plunger; 5022. Lower end of plunger; 601. Ball groove of end cover. DETAILED DESCRIPTION

[0031] Specific embodiment 1: Please refer to the accompanying drawings. In this embodiment, an anti-wear pawl flywheel is characterized by comprising a flywheel 1, an inner core 2, a pawl 3, a bearing structure 4 and a lubricating structure 5.

[0032] The flywheel 1 is an annular component with a toothed ratchet surface 102 formed around its inner ring. The outer circumference of the flywheel 1 is formed with ratchet teeth 101 that engage the chain. On both sides of the flywheel 1, an annular protrusion is formed at the root of the teeth of the toothed ratchet surface 102. Flywheel ball grooves 103 are formed on the inner edges of the annular protrusions on both sides.

[0033] The inner core 2 is a hollow stepped shaft component, arranged in three steps with gradually decreasing diameters along the axial direction. The flywheel 1 rotates outside the middle step. A circular inner core ball groove 203 is formed on the edge of the inner core 2's largest diameter step, near the flywheel 1. This inner core ball groove 203 and the flywheel ball groove 103 on the flywheel 1 side spatially envelop an annular raceway. Several steel balls are mounted within the raceway, forming a bearing structure 4 that enables coaxial rotation of the flywheel 1 and inner core 2. Two pawl mounting grooves 201 are formed symmetrically about the axis on the circumference of the middle shaft section of the inner core 2. These pawl mounting grooves 201 are arc-shaped grooves that smoothly taper to a shallower depth along the circumference and are tangential to the circumference of the middle shaft section. The largest diameter step of the inner core 2 is threadedly connected to the wheel axle during installation. The hollow right portion of the inner core 2 is splined for assembly and disassembly.

[0034] The pawl 3 is a thin, flat piece with one end thicker than the other. The thick end features an arcuate curved surface that matches the arcuate groove of the pawl mounting slot 201. The thin end features triangular ratchet teeth that match the toothed ratchet surface 102 of the flywheel 1, allowing for meshing transmission. The thicker end of the pawl 3 fits into the pawl mounting slot 201, allowing the arcuate surface to oscillate at a predetermined angle. When installed, the lower surface of the pawl 3 features a circular depression 301, with a lubrication hole 302 extending through the center of the depression 301.

[0035] The lubrication structure 5 includes an oil outlet 501, a plunger 502, an extrusion spring 503, an oil filling end cover 504 and an oil filling spring 505. A circular oil outlet 501 is provided in the middle of the pawl mounting groove 201 of the inner core 2. The circular oil outlet 501 is obliquely passed through the hollow center of the inner core 2, and the passing end portion is penetrated to form an end surface 5011 perpendicular to the perforation direction. The oil outlet 501 is divided into two upper and lower sections with different diameters, and the upper end diameter is smaller than the lower end diameter. The plunger 502 is a cylindrical part, divided into two upper and lower sections. The diameter of the cylindrical plunger upper end 5021 is smaller than the upper end diameter of the oil outlet hole 501, and the diameter of the cylindrical plunger lower end 5022 is larger than the plunger upper end 5021 but smaller than the lower end diameter of the oil outlet hole 501, and is movably embedded in the oil outlet hole 501. The upper surface of the plunger's upper end 5021 abuts the lower end of the swing spring 202, which in turn abuts and is encircled by the circular recess 301 on the lower surface of the pawl 3. A compression spring 503 is positioned within the lower aperture of the oil outlet hole 501, with one end abutting the lower surface of the plunger's lower end 5022 and the other end abutting the end surface 5011 formed at the central protrusion of the oil outlet hole 501. Under the elastic force of the compression spring 503, the stepped surface of the plunger 502 aligns with the stepped surface at the intersection of the two apertures of the oil outlet hole 501, separating the upper and lower sections of the oil outlet hole 501.

[0036] A circular end cap 6 is threadedly mounted on the outer side of the smallest stage of the inner core 2. Its diameter is larger than the inner diameter of the flywheel 1. A ball groove 601 is formed on the outer edge near the flywheel 1. This groove and the flywheel ball groove 103 of the flywheel 1 spatially enclose an annular raceway. Several steel balls are mounted within this raceway, forming another bearing structure 4. This prevents axial slippage when the flywheel 1 rotates coaxially with the inner core 2.

[0037] Working Principle: During rotation, the height of ratchet surface 102 is lower than the upper surface of pawl 3. For example, in Figure 3, the rider drives flywheel 1 clockwise via the chain. The teeth of ratchet surface 2 engage pawl 3, locking the connection and transmitting power to inner core 2, which is connected to the axle, causing the axle to rotate clockwise. When the rider coasts or pedals backward, flywheel 1 rotates counterclockwise relative to inner core 2. The teeth of ratchet surface 2 and pawl 3 cannot engage, and ratchet surface 102 continuously presses down on pawl 3 as it rotates, causing pawl 3 to bounce up and down. At this time, when the pawl 3 is pressed down, the swing spring 202 is compressed, and the compressed elastic force is transmitted downward to the plunger 502 abutting against it. Under the action of the downward pressure, the plunger 502 will overcome the upward elastic force of the extrusion spring 503 and move downward a short distance, so that the step surface of the plunger 502 is separated from the step surface of the oil outlet 501, and the upper and lower ends of the oil outlet are connected. The above action only occurs when the pawl 3 is pressed down and swung by the ratchet surface 102. When the pawl 3 swings upward, the connection of the oil outlet 501 will be blocked and disconnected by the plunger 502. One end of the inner core 2 is connected to the wheel shaft, and the other end is installed with the end cover 6. The middle hollow part of the inner core 2 is blocked to form a lubricating oil storage chamber, in which the lubricating oil is stored. During the above-mentioned oil outlet hole 501 connection process, the lubricating oil will flow out along the oil outlet hole, and under the guidance of the swing spring 202, it will flow from the lower surface of the pawl 3 through the lubrication hole 302 to the upper surface of the pawl 3, lubricating and protecting the upper surface of the pawl 3 that is constantly jumping and colliding to prevent wear.

[0038] Specific embodiment 2: Based on the specific embodiment 1, Figure 1 As shown, an oiling cap 504 and an oiling spring 505 are installed in the inner cavity of the inner core 2 where it connects to the axle. The left end of the oiling spring 505 abuts the axle, while the right end abuts the circular oiling cap 504, which matches the inner cavity. The spring force pushes the oiling cap 504 to the right. The lubricating oil in the right cavity of the oiling cap 504 is pressurized, allowing the oil outlet 501 to flow through more quickly, protecting the pawl 3.

[0039] The above description is only a preferred embodiment of the present invention and is not intended to be limiting. All variations, modifications, and substitutions within the spirit and principles of this design are within the scope of protection of this utility model.

Claims

1. A wear-resistant pawl flywheel, characterized in that: It includes a flywheel (1), an inner core (2), a pawl (3), a bearing structure (4) and a lubrication structure (5); The flywheel (1) is an annular part, and the inner ring is provided with a ratchet surface (102) for engaging with one end of the ratchet pawl (3) for transmission in a transmission state; The inner core (2) is a hollow stepped shaft part, and a pawl mounting groove (201) is formed on the circumferential surface of the middle shaft section. One end of the pawl (3) is embedded in the pawl mounting groove (201) to transmit the driving force from the flywheel (1); a swing spring (202) is provided below the pawl (3) to drive the pawl (3) to swing back and forth around the embedded end; The flywheel (1) is sleeved on the outer periphery of the middle shaft section of the inner core (2), and the two are connected to each other in a coaxial rotation manner via a bearing structure (4) provided on the inner core (2); The lubricating structure (5) is arranged at the pawl mounting groove (201) and is provided with a through hole connected to the center of the inner core (2) for discharging oil to lubricate the pawl (3) and prevent wear.

2. The wear-resistant pawl flywheel according to claim 1, characterized in that: The lubrication structure (5) includes an oil outlet hole (501), a plunger (502), an extrusion spring (503), an oil filling end cover (504) and an oil filling spring (505); The inner core (2) is provided with an oil outlet hole (501) at the middle position of the pawl mounting groove (201), which obliquely penetrates the hollow center of the inner core (2), and the protruding end portion penetrates to form an end surface (5011) perpendicular to the perforation direction; The oil outlet hole (501) is divided into two sections, upper and lower, with different diameters, and the diameter of the upper end is smaller than that of the lower end; The plunger (502) is a cylindrical part, divided into two sections, the upper and lower sections; the diameter of the cylindrical plunger upper end (5021) is smaller than the upper end diameter of the oil outlet hole (501); the diameter of the cylindrical plunger lower end (5022) is larger than the plunger upper end (5021) but smaller than the lower end diameter of the oil outlet hole (501), and is movably embedded in the oil outlet hole (501); the upper surface of the plunger upper end (5021) is in contact with the swing spring (202), squeezing The compression spring (503) is arranged in the lower end aperture of the oil outlet hole (501), with one end abutting against the lower surface of the lower end (5022) of the plunger, and the other end abutting against the end surface (5011) formed at the center through end of the oil outlet hole (501); the compression spring (503) is in a compressed state, driving the plunger (502) to move upward, and the step surface of the plunger (502) is in contact with the step surface at the junction of the two aperture sections of the oil outlet hole (501); The hollow right part of the inner core (2) is provided with a spline for disassembly and assembly, and the left part is provided with a vertically arranged oil filling end cover (504). The outer periphery of the oil filling end cover (504) fits the inner wall of the inner core (2), and the left end face of the oil filling end cover (504) abuts against the compressed oil filling spring (505). Driven by the oil filling spring (505), the oil filling end cover (504) as a whole tends to move to the right.

3. The wear-resistant pawl flywheel according to claim 2, characterized in that: The outer periphery of the flywheel (1) is provided with ratchet teeth (101) for engaging the chain; annular protrusions are provided on both sides of the flywheel (1) from the position of the tooth roots of the ratchet surface (102), and flywheel ball grooves (103) are provided on the inner edges of the annular protrusions on both sides.

4. The wear-resistant pawl flywheel according to claim 3, characterized in that: The inner core (2) is a hollow stepped shaft part, which is in a three-step ladder shape with gradually decreasing diameters in the axial direction, and the flywheel (1) is rotatably arranged outside the middle step; an inner core ball groove (203) is formed on the edge of the inner core (2) at the largest diameter step close to the flywheel (1), and the inner core ball groove (203) and the flywheel ball groove (103) on one side of the flywheel (1) are spatially enclosed to form an annular raceway, and a plurality of steel balls are installed in the raceway.

5. The wear-resistant pawl flywheel according to claim 4, characterized in that: The surface of the end where the ratchet (3) contacts the swing spring (202) is provided with a circular recess (301) having a diameter larger than that of the swing spring (202).

6. The wear-resistant pawl flywheel according to claim 5, characterized in that: A lubrication hole (302) penetrating the pawl (3) is formed in the center of the circular recess (301).

7. The wear-resistant pawl flywheel according to claim 5, characterized in that: When the pawl (3) rotates around the embedded end toward the inner core (2), the swing spring (202) exerts a downward driving force on the plunger (502), driving the plunger (502) to move toward the inner core (2). The step surface of the plunger (502) is separated from the step surface at the junction of the two apertures of the oil outlet hole (501), and the upper and lower sections of the oil outlet hole (501) are connected.

8. The wear-resistant pawl flywheel according to claim 7, characterized in that: The invention also includes an end cover (6); the end cover (6) is fixedly mounted on the outer side of the smallest end of the inner core (2); an end cover ball groove (601) is formed on the outer edge of the side close to the flywheel (1); the end cover ball groove (601) and the flywheel ball groove (103) of the flywheel (1) are spatially enclosed to form an annular raceway, and a plurality of steel balls are mounted in the raceway.

9. The wear-resistant pawl flywheel according to claim 8, characterized in that: After the end cover (6) is installed, the middle hollow portion of the inner core (2) is blocked by the end cover (6) and the oil filling end cover (504) respectively, forming a lubricating oil storage cavity in which lubricating oil is stored.

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