Patent Application
20130270055
1. Field of the Invention
The present invention relates to an electric starting device of a model engine, and more particularly to an electric starting device to assist in starting the model engine.
2. Description of the Prior Art
Most remote-controlled model cars use gasoline or methyl alcohol as the power source of the model engine. The model engine uses an electric starting device to assist in starting the model engine of the remote-controlled model car. The electric starting device comprises a motor, a switch and a plurality of gears. The gears are a deceleration gear unit. When in use, the switch is turned on to start the motor. The motor drives the gears. Through the gears, the driving force of the motor drives the model engine.
Although the conventional electric starting device can assist in starting the remote-controlled model car, the model engine will feed back to the electric starting device in accordance with the principle of inertia at the moment that the electric starting device starts the model engine. The model engine generates a feedback force in the reverse direction relative to the driving force of the motor. When the driving force of the motor is less than the feedback force of the model engine, the feedback force of the model engine will turn the motor reversely. The feedback force of the model engine and the driving force of the motor will generate a pull. If there is no any member to decelerate or absorb the feedback force of the model engine, the motor and the deceleration gear unit may be damaged. The conventional electric starting device consumes a lot of electricity and it is not easy to start the model engine, so the product is not competitive. Accordingly, the inventor of the present invention has devoted himself based on his many years of practical experiences to solve these problems and to invent an electric starting device which buffers the feedback force of the model engine, prevents the motor and the deceleration gear unit from being damaged, has lower power consumption and starts the model engine with ease.
The primary object of the present invention is to provide an electric starting device of a model engine which can buffer the feedback force generated by starting the model engine, preventing the motor and the deceleration gear from being damaged. The electric starting device of the present invention can lower the power consumption and can be started with ease.
In order to achieve the aforesaid object, an electric starting device of a model engine is provided. The electric starting device comprises a motor, a transmission unit, a clutch and a connecting unit.
The motor comprises a driving gear at an output end thereof.
The transmission unit comprises a first gear to mesh with the driving gear. The transmission unit further comprises a second gear. The first gear and the second gear are coaxial.
The clutch is disposed on a top surface of the first gear. The first gear comprises at least two limit posts disposed on a circumferential surface thereof and spaced equally. The clutch comprises clutch parts corresponding in number to the limit posts. The clutch parts have elongated through holes corresponding to the limit posts. The elongated through holes are slight larger than the limit posts. Two distances defined between two ends of each elongated hole and an axle center of the first gear are not equal. The clutch comprises a clutch cover. The clutch cover comprises an axle. The clutch cover is pivotally connected with the second gear through the axle. The bottom of the clutch cover has an opening to form an accommodation space therein. The limit posts and the clutch parts are accommodated in the clutch cover.
The connecting unit has one end connected to the model engine and another end pivotally connected to a connecting gear relative to the second gear.
The driving force of the motor is transmitted to the model engine through the clutch to enhance the starting capability of the model engine and to save electricity. When the feedback force of the model engine feeds back to the clutch, the clutch parts will disengage from the clutch cover to prevent the electric starting device from being damaged.
The driving force of the motor of the electric starting device of the present invention is transmitted to the model engine through the clutch to overcome the problems existed in the conventional electric starting device. The electric starting device of the present invention can lower the power consumption and can be started with ease. When the feedback force of the model engine feeds back to the clutch, the clutch parts will disengage from the clutch cover to prevent the electric starting device from being damaged.
Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings.
The motor 10 comprises a driving gear 11 at an output end thereof.
The transmission unit 20 comprises a first gear 21 to mesh with the driving gear 11. The first gear 21 has a central axial hole 211 and a recess 212 on a top thereof. The transmission unit 20 comprises a second gear 22. The first gear 21 and the second gear 22 are coaxial. The transmission unit 20 comprises a third gear 23 to mesh with the second gear 22. The transmission unit 20 comprises a fourth gear 24. The third gear 23 and the fourth gear 24 are coaxial.
The clutch 30 is located between the first gear 21 and the second gear 22. The first gear 21 comprises two limit posts 31 disposed on a circumferential surface thereof and spaced equally. The clutch 30 comprises two clutch parts 32 corresponding to the two limit posts 31. The two clutch parts 32 have a curved shape. The two clutch parts 32 have elongated through holes 321 corresponding to the limit posts 31. The elongated through holes 321 are slight larger than the limit posts 31. Through the elongated holes 321, the clutch parts 32 are limited by the limit posts 31. In this embodiment, two distances defined between two ends of each elongated hole 321 and an axle center of the first gear 21 are not equal. A first distance d1 defined between one end of each elongated hole 321 and the axle center of the first gear 21. A second distance d2 defined between the other end of each elongated hole 321 and the axle center of the first gear 21. The first distance d1 is greater than the second distance d2. The clutch 30 comprises a clutch cover 33. The clutch cover 33 has a cylindrical wall which is contact with outer edges of the clutch parts 32. The bottom of the clutch cover 33 has an opening which faces the recess 212 of the first gear 21. The clutch cover 33 comprises an axle 331 corresponding to the axial hole 211 of the first gear 21. One end of the axle 331 is inserted in the axial hole 211 of the first gear 21. Another end of the axle 331 extends out of the top of the clutch cover 33. Through the axle 331, the clutch cover 33 is pivotally connected with the second gear 21. The clutch cover 33 has an accommodation space therein. The limit posts 31 and the clutch parts 32 are accommodated in the clutch cover 33.
The connecting unit 40 has one end connected to the model engine 200 and another end pivotally connected to a connecting gear 41 relative to the fourth gear 24. The connecting gear 41 meshes with the fourth gear 24. The connecting gear 41 has a plurality of through holes 411 which are equally spaced. The connecting unit 40 has a plurality of connecting posts 42 corresponding in position to the through holes 411 of the connecting gear 41. Between the through holes 411 and the connecting posts 42 are respectively provided with buffer pads 43. Each of the buffer pads 43 has a plurality of buffer spaces 431. The buffer pads 43 are made of a resilient material.
Before the driving force of the motor 10 is transmitted to the model engine, the clutch parts 32 are moved toward the inner wall edge of the clutch cover 33. During this procedure, there is a time difference caused by the clutch parts 32 of the clutch 30 to be pushed toward the clutch cover 33. The motor 10 generates a slight idle running, not direct driving the load. By the buffer pads 43 to be pressed and deformed, the driving force is transmitted to the model engine 200. Accordingly, the motor 10 uses less electricity to drive the engine model 200. The electric starting device 100 of the present invention enhances the capability to start the model engine 200 and has an electricity-saving effect.
Although particular embodiments of the present invention have been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the present invention. Accordingly, the present invention is not to be limited except as by the appended claims.
