Disconnection operation warning device for marine single-cylinder engine turning gear
By installing a proximity switch and warning circuit for crankshaft bottom dead center detection on the crankshaft turning machine of a marine single-cylinder engine, real-time detection and warning of crankshaft position are achieved, solving the safety hazards caused by misoperation and ensuring operational safety.
Patent Information
- Application Number
- CN202510697013.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-28
- Publication Date
- 2025-10-31
AI Technical Summary
There is a safety hazard in disengaging the crankshaft of a marine single-cylinder engine. Operators may misoperate due to neglecting the position of the flywheel and crankshaft, causing the crankshaft to rotate and swing on its own, which poses a risk of collision.
Design a disengagement operation warning device, including a proximity switch for crankshaft bottom dead center detection, an engagement limit switch, a disengagement limit switch, and an operation warning box. The device uses circuit control of a bottom dead center indicator light and a buzzer to alert the operator to the crankshaft position and prevent misoperation.
It effectively indicates whether the crankshaft is at the bottom dead center position, avoids misoperation, reduces safety risks, and ensures operational safety.
Smart Images
Figure CN120867883A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to marine single-cylinder engines, and in particular to a disengagement warning device for a turning gear of a marine single-cylinder engine, belonging to the field of marine engine technology. Background Technology
[0002] The turning gear is a device on a marine engine, mounted on the engine base 4, such as... Figure 2 As shown, it consists of a motor 18, a drive gear 19, a handle 20, etc. Figure 1 When installing or repairing components on a marine engine, a turning gear is required. To use it, first operate handle 20 to engage the drive gear 19 with the flywheel 2 on the marine engine. (See...) Figure 2 Then, the motor 18 is energized, at which point the turning gear starts working, driving the gear 19 to rotate, which in turn drives the flywheel 2 and crankshaft 3 to rotate, thus realizing the turning of the marine engine. The turning gear is equipped with a meshing limit switch 8, which is used to detect the position of the handle 20 when the gears are engaged and the turning gear 1 is in the non-disengaged state. When the marine engine is running, the turning gear is not in operation, so it needs to be disengaged after installation and maintenance work is completed and before the marine engine is run, that is, the drive gear 19 needs to be disengaged from the flywheel 2 on the marine engine and placed in a non-meshing state.
[0003] For marine single-cylinder engines, due to the relatively small number of cylinders and the presence of heavy flywheels and counterweights at the front and rear ends of the crankshaft, if the crankshaft is not at bottom dead center after the turning gear is disengaged, the crankshaft, flywheel, and counterweight will rotate and oscillate under gravity until they reach bottom dead center. Therefore, disengaging the turning gear carries a certain risk; people or objects near the flywheel may be grazed or injured by the rotating flywheel.
[0004] Although there are nameplates on the crankshaft turning machine that require operators to rotate the crankshaft to the bottom dead center position before disengaging the crankshaft, there are no obvious warnings about disengagement. Operators often fail to notice the nameplates or forget to turn the crankshaft when operating the machine as if it were a multi-cylinder engine, which poses a huge safety hazard. Summary of the Invention
[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a disengagement operation warning device for a turning gear of a marine single-cylinder engine. When the turning gear is disengaged, the position of the crankshaft is detected, indicating whether the crankshaft is at the bottom dead center balance position. If not, an alarm is issued to avoid operator misoperation and reduce the safety risks caused by improper operation.
[0006] To achieve the above objectives, the present invention provides the following technical solution:
[0007] A disengagement operation warning device for a turning gear of a marine single-cylinder engine is installed on the marine single-cylinder engine, which includes a flywheel, a crankshaft, and a base. The flywheel has a marking block for indicating that the flywheel and crankshaft are at the bottom dead center position. The turning gear is installed on the base and, through engagement with the flywheel, turns the flywheel and crankshaft, enabling switching between engagement and disengagement states. The disengagement operation warning device comprises:
[0008] A crankshaft bottom dead center detection proximity switch is fixed on the machine base and its position corresponds to the mark block on the flywheel. It is used to detect whether the flywheel and crankshaft are at the bottom dead center position. When the flywheel and crankshaft are at the bottom dead center position, the crankshaft bottom dead center detection proximity switch is facing the mark block, thereby changing from normally open to closed to conduct the circuit.
[0009] A meshing limit switch is fixed on the turning gear and is used to detect the meshing position of the turning gear. When the turning gear is in the meshing position, the meshing limit switch remains open. Once the turning gear is disengaged from the meshing position, the meshing limit switch immediately changes from open to closed.
[0010] A disengagement limit switch is fixed on the turning gear and is used to detect the disengagement position of the turning gear. When the turning gear is in the disengagement position, the disengagement limit switch remains open. Once the turning gear is disengaged from the disengagement position, the disengagement limit switch immediately changes from open to closed.
[0011] An operation warning box is fixed on the turning machine;
[0012] The warning circuit, installed in the operation warning box and connected to the engagement limit switch and disengagement limit switch, is used to provide a prompt that disengagement operation can be performed when the flywheel and crankshaft are at the bottom dead center position in the engagement state of the turning gear and flywheel, and to provide an audible and visual warning when the flywheel and crankshaft are not at the bottom dead center position and a disengagement misoperation occurs.
[0013] Furthermore, the warning circuit includes a relay, a bottom dead center indicator light, and a buzzer; the bottom dead center indicator light and the buzzer are mounted on the outer shell of the operation warning box and are used to issue visual and audible warning signals to the operator; the relay is located inside the operation warning box, the coil of the relay is connected to the proximity switch for crankshaft bottom dead center detection, the normally open contact of the relay is connected to the bottom dead center indicator light, the normally closed contact of the relay is connected to the buzzer, and the engagement limit switch and the disengagement limit switch are connected in series between the normally open contact and the normally closed contact;
[0014] When the crankshaft turning gear is engaged and the flywheel and crankshaft reach the bottom dead center (BDC) position, the marker block aligns with the crankshaft BDC detection proximity switch. The crankshaft BDC detection proximity switch changes from normally open to closed, energizing the relay coil. The normally closed contact opens, the buzzer goes out, and the normally open contact closes, illuminating the BDC indicator light. This indicates that the flywheel and crankshaft are currently at BDC, allowing the crankshaft turning gear to disengage. When the flywheel and crankshaft are not at BDC, the marker block moves away from the crankshaft BDC detection proximity switch. When the proximity switch used for crankshaft bottom dead center detection is switched to normally open, the circuit is de-energized, causing the relay coil to lose power. The normally closed contact closes, while the normally open contact opens, and the bottom dead center indicator light goes out, indicating that the flywheel and crankshaft are not currently at bottom dead center, and the disengagement operation of the turning gear cannot be performed. If the disengagement operation of the turning gear is initiated at this time, since the normally closed contact remains closed, the engagement limit switch changes from normally open to closed, while the disengagement limit switch remains closed. In this case, the buzzer is energized and emits an audible and visual warning, prompting the user to immediately stop the disengagement operation of the turning gear.
[0015] Furthermore, the warning circuit is powered by an external power source.
[0016] Furthermore, the proximity switch for crankshaft bottom dead center detection is fixed to the base via a mounting bracket.
[0017] Compared with the prior art, the present invention achieves the following beneficial effects:
[0018] This invention solves the problem of operator misoperation due to neglecting the position of the flywheel and crankshaft. It provides clear prompts that the turning gear disengagement operation can be performed when the flywheel and crankshaft are at the bottom dead center position. For turning gear disengagement operations started when the flywheel and crankshaft are not at the bottom dead center, it promptly issues audible and visual warnings to remind the operator to immediately stop the disengagement operation. This avoids misoperation of the turning gear disengagement under inappropriate conditions, reduces the risk of misoperation of the turning gear disengagement operation, and ensures the safety of turning gear disengagement operations for marine single-cylinder engines.
[0019] This invention can be used for disengaging the turning gear of all marine single-cylinder engines. Attached Figure Description
[0020] Figure 1 For existing turning gear machines.
[0021] Figure 2 This is a schematic diagram of the installation of the present invention.
[0022] Figure 3 This is a schematic diagram of the structure of the present invention.
[0023] Figure 4 This is the circuit schematic diagram of the present invention.
[0024] In the picture,
[0025] 1—Crankshaft turning mechanism, 2—Flywheel, 3—Crankshaft, 4—Base, 5—Proximity switch for crankshaft bottom dead center detection, 6—Marker block, 7—Mounting bracket, 8—Engagement limit switch, 9—Disengagement limit switch, 10—Operation warning box, 11—External power supply, 12—Relay, 13—Normally open contact, 14—Bottom dead center indicator light, 15—Normally closed contact, 16—Buzzer, 17—Wire, 18—Motor, 19—Drive gear, 20—Handle. Detailed Implementation
[0026] The following detailed description of the disengagement warning device for a marine single-cylinder engine turning gear, with reference to the accompanying drawings and specific embodiments, is intended to further illustrate the present invention, but should not be construed as limiting the scope of protection of the present invention.
[0027] This invention is used for disengaging the crankshaft turning gear in marine single-cylinder engines. When the crankshaft is at bottom dead center, the operator is prompted that the crankshaft turning gear can be disengaged. If the crankshaft is not at bottom dead center, the operator is warned that the crankshaft turning gear must not be disengaged.
[0028] like Figure 2 and Figure 3 As shown, the marine single-cylinder engine includes a flywheel 2, a crankshaft 3, and a base 4; a turning gear 1 is mounted on the base 4, and the turning gear 1 is equipped with an engagement limit switch 8. When the handle 20 is in the engagement position of the turning gear 1, the engagement limit switch 8 remains open. Once the handle 20 is disengaged from the engagement position of the turning gear 1, the engagement limit switch 8 immediately changes from open to closed; a marking block 6 is provided on the flywheel 2 to mark that the flywheel 2 and the crankshaft 3 are at the bottom dead center position.
[0029] The technical solution of this invention is as follows: Please refer to Figure 3 Install a crankshaft bottom dead center detection proximity switch 5 on flywheel 2. Utilize the existing marker block 6 on flywheel 2. When crankshaft 3 is turned to bottom dead center, marker block 6 is directly facing crankshaft bottom dead center detection proximity switch 5. Utilize the existing engagement limit switch 8 on cranking machine 1 to detect the engagement position of cranking machine 1. Install a disengagement limit switch 9 on cranking machine 1 to detect the disengagement position of cranking machine 1. Install an operation warning box 10 on cranking machine 1. The box is equipped with a bottom dead center indicator light 14 (green) and a non-bottom dead center operation alarm buzzer 16 (red).
[0030] When crankshaft 3 is turned to bottom dead center, the bottom dead center indicator light 14 (green) on the operation warning box 10 will light up, informing the operator that the disengagement operation can be performed; if crankshaft 3 is not at bottom dead center, as long as crankshaft 1 is slightly disengaged, buzzer 16 (red) will sound a warning sound, reminding the operator not to disengage crankshaft 1.
[0031] Example
[0032] Please see Figure 2 and Figure 3 The disengagement operation warning device includes a crankshaft bottom dead center detection proximity switch 5, a disengagement limit switch 9, and an operation warning box 10. The crankshaft bottom dead center detection proximity switch 5 is mounted on a mounting bracket 7, positioned corresponding to the marker block 6 on the flywheel 2. The mounting bracket 7 is fixed to the machine base 4. When the crankshaft 3 is turned to bottom dead center, the crankshaft bottom dead center detection proximity switch 5 is directly opposite the marker block 6 on the flywheel 2, thus changing from normally open to closed and simultaneously activating the circuit. The disengagement limit switch 9 is fixed to the turning gear 1 and is used to detect the position of the handle 20 when the turning gear 1 is disengaged. When the handle 20 is not in the disengaged position of the turning gear 1, the disengagement limit switch 9 remains normally closed; when the handle 20 is in the disengaged position of the turning gear 1, the disengagement limit switch 9 changes from normally closed to open. Please refer to [link to relevant documentation]. Figure 4 The operation warning box 10 is installed on the crankshaft turning machine 1 and is used to house the warning circuit. The operation warning box 10 is connected to an external power supply 11, which supplies power to the warning circuit. A bottom dead center indicator light 14 and a buzzer 16 are installed on the outer shell of the operation warning box 10 to provide visual and audible warning signals to the operator. A relay 12 is installed inside the operation warning box 10. The relay 12 is connected to the crankshaft bottom dead center detection proximity switch 5. The normally open contact 13 of the relay 12 is connected to the bottom dead center indicator light 14, and the normally closed contact 15 of the relay 12 is connected to the buzzer 16. Engagement limit switches 8 and disengagement limit switches 9 are connected in series between the normally open contact 13 and the normally closed contact 15. All connections between components in the warning circuit are made via wires 17.
[0033] The working principle of the disengagement warning device described in this invention is as follows:
[0034] Please see Figure 3 and Figure 4When the crankshaft turning machine 1 is engaged and the crankshaft 3 is turned to the bottom dead center (BDC) position, the marker block 6 on the flywheel 2 is aligned with the crankshaft BDC detection proximity switch 5. At this time, the circuit is connected, the coil of relay 12 is energized, the normally closed contact 15 opens, the buzzer 16 (red) does not work, while the normally open contact 13 closes, and the BDC indicator light 14 (green) illuminates, informing the operator that the crankshaft 3 has reached BDC and the crankshaft turning machine 1 can be disengaged. When the crankshaft 3 is no longer at BDC, the marker block 6 on the flywheel 2 moves away from the crankshaft BDC detection proximity switch 5. At this time, the circuit is de-energized, the coil of relay 12 is de-energized, the normally closed contact 15 closes, and the normally open contact 13 closes. When contact 13 opens, the bottom dead center indicator 14 (green) goes out, informing the operator that the crankshaft 3 is not at bottom dead center and the turning gear 1 cannot be disengaged. If the operator accidentally starts disengaging the turning gear 1 at this time, once the handle 20 disengages from the engaging position of the turning gear 1, even a slight disengagement will cause the normally closed contact 15 to remain closed, the contacts in the engagement limit switch 8 to change from normally open to closed, and the contacts in the disengagement limit switch 9 to remain closed (because the handle 20 has not yet reached the disengagement position of the turning gear 1). At this time, the buzzer 16 (red) will be energized and emit an audible and visual warning to remind the operator to immediately stop the disengagement operation of the turning gear 1.
[0035] In short, if the bottom dead center indicator 14 is lit (green), the disengagement operation of the turning gear 1 is permitted; if the buzzer 16 emits an audible and visual warning (red), the disengagement operation of the turning gear 1 should be stopped immediately.
[0036] The scope of protection claimed by this invention is not limited to the above embodiments, but should also include other variations and alternatives that are obvious to this invention.
Claims
1. A disengagement operation warning device for a turning gear for a marine single-cylinder engine, installed on the marine single-cylinder engine, the marine single-cylinder engine including a flywheel, a crankshaft, and a base, wherein the flywheel is provided with a marking block for indicating that the flywheel and crankshaft are at the bottom dead center position, the turning gear is installed on the base, and can switch between two states of engagement and disengagement by engaging with the flywheel to turn the flywheel and crankshaft; characterized in that, The disengagement operation warning device includes: A crankshaft bottom dead center detection proximity switch is fixed on the machine base and its position corresponds to the mark block on the flywheel. It is used to detect whether the flywheel and crankshaft are at the bottom dead center position. When the flywheel and crankshaft are at the bottom dead center position, the crankshaft bottom dead center detection proximity switch is facing the mark block, thereby changing from normally open to closed to conduct the circuit. A meshing limit switch is fixed on the turning gear and is used to detect the meshing position of the turning gear. When the turning gear is in the meshing position, the meshing limit switch remains open. Once the turning gear is disengaged from the meshing position, the meshing limit switch immediately changes from open to closed. A disengagement limit switch is fixed on the turning gear and is used to detect the disengagement position of the turning gear. When the turning gear is in the disengagement position, the disengagement limit switch remains open. Once the turning gear is disengaged from the disengagement position, the disengagement limit switch immediately changes from open to closed. An operation warning box is fixed on the turning machine; The warning circuit, installed in the operation warning box and connected to the engagement limit switch and disengagement limit switch, is used to provide a prompt that disengagement operation can be performed when the flywheel and crankshaft are at the bottom dead center position in the engagement state of the turning gear and flywheel, and to provide an audible and visual warning when the flywheel and crankshaft are not at the bottom dead center position and a disengagement misoperation occurs.
2. The disengagement operation warning device for a marine single-cylinder engine turning gear according to claim 1, characterized in that, The warning circuit includes a relay, a bottom dead center indicator light, and a buzzer. The bottom dead center indicator light and the buzzer are mounted on the outer shell of the operation warning box and are used to provide visual and audible warning signals to the operator. The relay is located inside the operation warning box. The coil of the relay is connected to the proximity switch for crankshaft bottom dead center detection. The normally open contact of the relay is connected to the bottom dead center indicator light, and the normally closed contact of the relay is connected to the buzzer. The engagement limit switch and the disengagement limit switch are connected in series between the normally open contact and the normally closed contact. When the crankshaft turning gear is engaged and the flywheel and crankshaft reach the bottom dead center (BDC) position, the marker block aligns with the crankshaft BDC detection proximity switch. The crankshaft BDC detection proximity switch changes from normally open to closed, energizing the relay coil. The normally closed contact opens, the buzzer goes out, and the normally open contact closes, illuminating the BDC indicator light. This indicates that the flywheel and crankshaft are currently at BDC, allowing the crankshaft turning gear to disengage. When the flywheel and crankshaft are not at BDC, the marker block moves away from the crankshaft BDC detection proximity switch. When the proximity switch used for crankshaft bottom dead center detection is switched to normally open, the circuit is de-energized, causing the relay coil to lose power. The normally closed contact closes, while the normally open contact opens, and the bottom dead center indicator light goes out, indicating that the flywheel and crankshaft are not currently at bottom dead center, and the disengagement operation of the turning gear cannot be performed. If the disengagement operation of the turning gear is initiated at this time, since the normally closed contact remains closed, the engagement limit switch changes from normally open to closed, while the disengagement limit switch remains closed. In this case, the buzzer is energized and emits an audible and visual warning, prompting the user to immediately stop the disengagement operation of the turning gear.
3. The disengagement operation warning device for a marine single-cylinder engine turning gear according to claim 2, characterized in that, The warning circuit is powered by an external power source.
4. The disengagement operation warning device for a marine single-cylinder engine turning gear according to claim 1, characterized in that, The proximity switch for crankshaft bottom dead center detection is fixed to the base via a mounting bracket.