High-speed feeding equipment for LED production

Abstract

The invention belongs to the technical field of LED feeding, and provides high-speed feeding equipment for LED production, which comprises a machine table, a rotating wheel is arranged in the middle of the upper end of the machine table, a center shaft is fixedly connected to the circle center of the rotating wheel, and a plurality of electric push rods are fixedly connected to the periphery of the rotating wheel; the two LED pins are respectively and accurately in full contact with the two test electrodes, the phenomena of wrong test, side leakage and the like of the LEDs are avoided, accurate power-on test on each LED can be completed before feeding and conveying, so that each LED fed and conveyed out can be normally powered on and used, the righting and testing processes and the feeding process are carried out in parallel, and the production efficiency is improved. The LED feeding device is suitable for feeding LEDs of various shapes, sizes, models and specifications, the feeding function is diversified, the working procedures are integrated and optimized, time is saved, the production speed is increased, the production efficiency is improved, and the production cost is reduced. The problems that an existing LED feeding device is inconvenient to centralize LED pins, the pins are difficult to make accurate contact with test electrodes, and the feeding efficiency is reduced are solved.

Description

Technical Field

[0001] The invention belongs to the technical field of LED feeding, and provides a high-speed feeding device for LED production. Background Art

[0002] Light-emitting diodes, or LEDs for short, are a commonly used light-emitting device that emits light by releasing energy through the recombination of electrons and holes. They are widely used in the field of lighting. Light-emitting diodes can efficiently convert electrical energy into light energy and have a wide range of uses in modern society, such as lighting, flat-panel displays, signal indication, and medical devices. Like ordinary diodes, light-emitting diodes are composed of a PN junction and also have unidirectional conductivity. When a forward voltage is applied to the light-emitting diode, the holes injected from the P region into the N region and the electrons injected from the N region into the P region recombine with the electrons in the N region and the holes in the P region within a few microns near the PN junction, respectively, to produce spontaneously radiated fluorescence. The energy states of electrons and holes in different semiconductor materials are different, and the amount of energy released when electrons and holes recombine is different. The more energy released, the shorter the wavelength of the light emitted. Commonly used diodes are those that emit red, green, or yellow light. The reverse breakdown voltage of a light-emitting diode is greater than 5 volts; its forward volt-ampere characteristic curve is very steep, and a current-limiting resistor must be connected in series to control the current passing through the diode when used. When producing various electrical equipment, high-speed loading equipment is needed to quickly transfer multiple LEDs to multiple PCB printed circuit boards in large quantities, so that the LEDs can be soldered and assembled into the PCB printed circuit board circuits.

[0003] LEDs need to be tested to ensure good conductivity before they can be loaded. Before loading, a preliminary process needs to be set up to power on each LED for testing. Since LEDs of different shapes, sizes, models and specifications are limited by the size of the equipment space during the test, the LED pins are sometimes distorted or the pin spacing is inconsistent, making it difficult for the pins to accurately and fully contact the test electrodes, which can easily lead to inaccurate LED testing. Before the test, additional equipment needs to be configured in advance to pre-straighten the LED pins. The pin positions of some LEDs with special shapes, sizes, models and specifications are different, and the LED pin positions need to be adjusted in advance. This makes the process scattered, the loading function is limited and single, and the loading efficiency is reduced, which is not conducive to improving production efficiency. Summary of the invention

[0004] The technical problem to be solved by the present invention is to overcome the defects of the prior art and solve the problem that the existing LED feeding device is inconvenient to straighten the LED pins, making it difficult for the pins to accurately contact the test electrodes, resulting in reduced feeding efficiency.

[0005] The technical solution adopted by the present invention to solve the technical problem is: a high-speed feeding device for LED production, comprising a machine platform, a rotating wheel is arranged in the middle of the upper end of the machine platform, the center of the rotating wheel is fixedly connected to a central axis, a plurality of electric push rods are fixedly connected around the rotating wheel, and the lower ends of the electric push rods are fixedly connected to vacuum suction cups;

[0006] A loading cylinder, a test seat, a first straightening turntable, a second straightening turntable and a reversing turntable are sequentially arranged at the upper end of the machine platform and adjacent to any one side of the rotating wheel. A protrusion is integrally formed on the upper end of the reversing turntable. A pair of test electrodes are installed on the upper end of the test seat.

[0007] The upper end of the first straightening turntable is connected to a plurality of first clamping claws through mechanical transmission, and the inner ends of the first clamping claws are connected to a plurality of first clamping fixtures through mechanical transmission;

[0008] The second straightening turntable is connected to a plurality of second clamping claws through mechanical transmission, and the inner ends of the second clamping claws are connected to a plurality of second clamping fixtures through mechanical transmission.

[0009] In a preferred technical solution of the present invention, a control panel is installed at any corner of the upper end of the machine.

[0010] In a preferred technical solution of the present invention, the lower end of the central shaft is transmission-connected to a first motor, and the lower end of the first motor is fixedly connected to the upper end of the machine platform.

[0011] In a preferred technical solution of the present invention, a first vacuum pipe opening is opened at the upper end of the electric push rod and passes through the interior of the adjacent vacuum suction cup, a second vacuum pipe opening is opened around the upper end of the central axis, and a hose is connected between the first vacuum pipe opening and the second vacuum pipe opening via a flange.

[0012] In a preferred technical solution of the present invention, a feeding rail and a hopper are connected to the upper end of the platform and adjacent to either side of the rotating wheel through mechanical transmission, and the feeding rail is connected to a vibration plate at one end away from the rotating wheel through mechanical transmission. The lower end of the vibration plate is fixedly connected to the upper end of the platform, and a hopper is installed around the rotating wheel and adjacent to either side of the vibration plate.

[0013] In a preferred technical solution of the present invention, the end of the reversing turntable away from the rotating wheel is connected to a second motor through a synchronous belt transmission, and the lower end of the second motor is fixedly connected to the upper end of the machine platform.

[0014] In a preferred technical solution of the present invention, the lower end of the second straightening turntable is transmission-connected to a third motor, the lower end of which is fixedly connected to the upper end of the machine platform; the lower end of the first straightening turntable is transmission-connected to a fourth motor, the lower end of which is fixedly connected to the upper end of the machine platform.

[0015] In a preferred technical solution of the present invention, a loading track is installed on the upper end of the machine platform and adjacent to one side of the rotating wheel, and the loading track is connected to the loading barrel through mechanical transmission.

[0016] In a preferred technical solution of the present invention, a plurality of material guide grooves are provided inside the feeding track, a plurality of protective sheets are provided on the upper end of the feeding track, a plurality of sensors installed on the upper end of the feeding track are provided between two adjacent protective sheets, a plurality of through holes aligned and matching the shape of the sensors are provided on the surface of the protective sheets, and the ends of the sensors extend into the adjacent through holes.

[0017] In a preferred technical solution of the present invention, a plurality of air suction ports are installed on the periphery of the feeding track, and a vibrator is installed at the lower end of the feeding track.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] The first motor drives the central axis to drive the wheel to rotate on the upper end of the machine. The rotating wheel will simultaneously drive multiple electric push rods to revolve around the central axis. The position of each electric push rod is switched by rotating the wheel, and the corresponding vacuum suction cup is driven to revolve around the central axis to switch positions in turn, so that each vacuum suction cup can take turns to suck each LED and grab it and place it in the first straightening turntable, the second straightening turntable, and the reversing turntable in turn, so that the LED pins are straightened and straightened, and the LED pins are adjusted. The spacing and position of the LED pins are respectively accurately contacted with the two test electrodes to avoid the phenomenon of LED mismeasurement and leakage. Each LED can be accurately powered on before feeding and conveying to ensure that each LED fed out can be powered on and used normally, so that the straightening and testing processes are carried out in parallel with the feeding process, which is suitable for feeding LEDs of various shapes, sizes, models and specifications. The feeding function is diversified, so that the process is integrated and optimized, which is conducive to saving time, speeding up production speed, and improving production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a left view of the overall structure of the present invention;

[0021] Figure 2 It is a partial enlarged view of structure A of the present invention;

[0022] Figure 3 It is a right view of the overall structure of the present invention;

[0023] Figure 4 It is a partial enlarged view of structure B of the present invention;

[0024] Figure 5 It is a left view of the feeding track of the present invention;

[0025] Figure 6 It is a right view of the feeding track of the present invention;

[0026] Figure 7 It is a schematic diagram of the internal structure of the feeding track of the present invention.

[0027] In the figure: 1, machine; 2, control panel; 3, hopper; 4, rotating wheel; 5, first vacuum pipe mouth; 6, center axis; 7, vacuum suction cup; 8, second vacuum pipe mouth; 9, electric push rod; 10, first motor; 11, first straightening turntable; 12, first clamping claw; 13, first clamping fixture; 14, reversing turntable; 15, second motor; 16, bump; 17, loading barrel; 18, test seat; 19, test electrode; 20, second straightening turntable; 21, second clamping claw; 22, second clamping fixture; 23, third motor; 24, fourth motor; 25, feeding rail; 26, vibration plate; 27, loading rail; 28, exhaust port; 29, vibrator; 30, sensor; 31, protective sheet; 32, guide trough. DETAILED DESCRIPTION

[0028] See also Figure 1-7 The present invention provides a technical solution: a high-speed feeding equipment for LED production, comprising a machine 1, a rotating wheel 4 is arranged in the middle of the upper end of the machine 1, a central axis 6 is fixedly connected to the center of the rotating wheel 4, a plurality of electric push rods 9 are fixedly connected around the rotating wheel 4, and a vacuum suction cup 7 is fixedly connected to the lower end of the electric push rods 9; a feeding cylinder 17, a test seat 18, a first straightening turntable 11, a second straightening turntable 20 and a reversing turntable 14 are arranged in sequence on the upper end of the machine 1 and adjacent to any side of the rotating wheel 4, a bump 16 is integrally formed on the upper end of the reversing turntable 14, and a pair of test electrodes 19 are installed on the upper end of the test seat 18; a feeding rail 25 and a hopper 3 are connected to the upper end of the machine 1 and adjacent to any side of the rotating wheel 4 through mechanical transmission, and a vibration plate 26 is connected to the feeding rail 25 away from the rotating wheel 4 through mechanical transmission, and a vibration plate 26 is connected to the feeding rail 25 through mechanical transmission. The lower end of the moving plate 26 is fixedly connected to the upper end of the machine 1, and a hopper 3 is installed around the rotating wheel 4 and adjacent to any side of the vibration plate 26; a control panel 2 is installed at any corner of the upper end of the machine 1, and the control panel 2 can be used to control the operation of the entire feeding equipment, and the LED is placed in the hopper 3, and the hopper 3 is suspended just above the vibration plate 26. The LED is concentrated and dropped into the vibration plate 26 through the hopper 3, and the LED is fed into the feeding rail 25 by relying on the regular and periodic vibration of the vibration plate 26. The feeding rail 25 has a long and narrow space width that can only accommodate a single row of LEDs. The LEDs crawl one by one inside the feeding rail 25 to the other end of the feeding rail 25 close to the rotating wheel 4, and the LEDs approach each vacuum suction cup 7 of the rotating wheel 4 one by one, so that the vacuum suction cup 7 can grab the LED.

[0029] The lower end of the central shaft 6 is transmission-connected to a first motor 10, and the lower end of the first motor 10 is fixedly connected to the upper end of the machine 1. The first motor 10 drives the central shaft 6 to drive the rotating wheel 4 to rotate at the upper end of the machine 1. The rotating rotating wheel 4 will simultaneously drive multiple electric push rods 9 to revolve around the central shaft 6. Multiple vacuum suction cups 7 and multiple electric push rods 9 will simultaneously revolve around the central shaft 6. The position of each electric push rod 9 is switched by rotating the rotating wheel 4, so as to drive the corresponding vacuum suction cup 7 to revolve around the central shaft 6 and switch positions in turn, so that each vacuum suction cup 7 can contact each LED transmitted from the feeding rail 25 in turn.

[0030] The upper end of the electric push rod 9 is provided with a first vacuum pipe port 5 which is connected to the inside of the adjacent vacuum suction cup 7, and the upper end of the central axis 6 is provided with a second vacuum pipe port 8. A hose is connected between the first vacuum pipe port 5 and the second vacuum pipe port 8 through a flange. The vacuum suction cup 7 is connected to the vacuum pump by the hose connected between the first vacuum pipe port 5 and the adjacent second vacuum pipe port 8. The vacuum pump can be installed inside the machine 1, and the vacuum pump is used to generate a "negative pressure" suction force on the corresponding vacuum suction cup 7 along the hose connected between the first vacuum pipe port 5 and the adjacent second vacuum pipe port 8. The vacuum suction cup 7 absorbs each LED transmitted from the feeding rail 25 one by one as the rotating wheel 4 rotates, and each LED is suspended around the rotating wheel 4 one by one by the vacuum suction cup 7. Each vacuum suction cup 7 absorbs and grasps an LED and revolves around the central axis 6 as the rotating wheel 4 rotates. The LEDs pass over the first straightening turntable 11, the second straightening turntable 20, the reversing turntable 14, the test electrode 19, and the loading barrel 17 one by one.

[0031] Each electric push rod 9 controls the corresponding vacuum suction cup 7 to perform lifting movement, so that each vacuum suction cup 7 can move away from and approach the first straightening turntable 11, the second straightening turntable 20, the reversing turntable 14, the test electrode 19, and the top of the loading barrel 17. The rotating wheel 4 rotates intermittently so that each vacuum suction cup 7 can intermittently revolve around the central axis 6, and the vacuum suction cup 7 is electrically controlled to adsorb and release the LED. A matching infrared sensor is installed near each vacuum suction cup 7 to sense the moving position of the LED based on the infrared ranging principle. When the LED approaches the first straightening turntable 11, the second straightening turntable 20, the reversing turntable 14, the test electrode 19, and the top of the loading barrel 17, it will be sensed by the corresponding sensor, and the sensor will cut off the power of the vacuum suction cup 7 to release the LED, and the vacuum suction cup 7 will place the LED in the first straightening turntable 11, the second straightening turntable 20, the reversing turntable 14, the test electrode 19, and the top of the loading barrel 17 in turn.

[0032] The upper end of the first straightening turntable 11 is connected to a plurality of first clamping claws 12 through mechanical transmission, and the inner ends of the first clamping claws 12 are connected to a plurality of first clamping fixtures 13 through mechanical transmission. When the vacuum suction cup 7 places the LED on the first straightening turntable 11, the first clamping claw 12 moves on the first straightening turntable 11 by hydraulic drive, and the four first clamping claws 12 make the corresponding four first clamping fixtures 13 support the outer periphery of the LED, so that the LED is fixed on the first straightening turntable 11, so that the LED is located in the center of the first straightening turntable 11, and the placement position of the LED is adjusted so that the LED is aligned directly below the vacuum suction cup 7. The lower end of the first straightening turntable 11 is connected to the fourth motor 24 through transmission, and the lower end of the fourth motor 24 is fixedly connected to the upper end of the machine 1. The fourth motor 24 drives the first straightening turntable 11 to rotate so that the orientation of the LED is adjusted, thereby changing the clamping posture of the LED to facilitate the vacuum suction cup 7. The empty suction cup 7 is powered on again to suck up the LED. The LED and the center of the vacuum suction cup 7 are in close contact with each other, so that the vacuum suction cup 7 grabs the LED and places it on the reversing turntable 14. The first straightening turntable 11 plays a role in straightening the LED, so that the vacuum suction cup 7 places the LED on the reversing turntable 14. The reversing turntable 14 is connected to the second motor 15 at the end away from the rotating wheel 4 through a synchronous belt drive. The lower end of the second motor 15 is fixedly connected to the upper end of the machine 1. The second motor 15 is used to drive the reversing turntable 14 to rotate. The reversing turntable 14 rotates the position of the LED by 180 degrees. The reversing turntable 14 reverses the positive and negative poles of the LED pins so that the LED pins grabbed by the vacuum suction cup 7 correspond to the positive and negative poles of the test electrode 19. At the same time, the protrusion 16 forks and straightens multiple pins of the LED, and the protrusion 16 adjusts the pin spacing. The protrusion 16 arranges multiple pins of the LED neatly to avoid clutter.

[0033] The lower end of the second righting turntable 20 is connected to a third motor 23, and the lower end of the third motor 23 is fixedly connected to the upper end of the machine 1. The third motor 23 is used to drive the second righting turntable 20 to rotate. Similarly, the working principle of the second righting turntable 20 is consistent with the working principle of the first righting turntable 11, and the function of the second righting turntable 20 is consistent with the function of the first righting turntable 11. The second righting turntable 20 is connected to a plurality of second clamping claws 21 through mechanical transmission, and the inner ends of the second clamping claws 21 are connected to a plurality of second clamping fixtures 22 through mechanical transmission. The LED is also clamped by the second clamping claw 21 and the second clamping fixture 22. The working principle and function of the second straightening turntable 20 are no longer repeated. The second straightening turntable 20 adjusts the placement of the LED according to the position of the test electrode 19, so that the vacuum suction cup 7 can accurately grasp the LED and place it on the test seat 18 to align it accurately with the test electrode 19 and fully contact it. The two test electrodes 19 are respectively positive and negative to energize the positive and negative poles of the two pins of the LED. If the LED lights up, it means that the LED power-on test is normal, so as to verify that the LED is a qualified material.

[0034] The test seat 18 is provided with a photosensor to sense the light emitted by the LED. The photosensor sends a feedback signal to the vacuum suction cup 7. The vacuum suction cup 7 grabs the LED from the test seat 18, and the rotating wheel 4 prompts the vacuum suction cup 7 to transfer the tested LED to the inside of the loading barrel 17. A loading track 27 is installed on the upper end of the machine 1 and adjacent to the rotating wheel 4. The loading track 27 is connected to the loading barrel 17 through mechanical transmission. There is a conveyor belt between the loading barrel 17 and the loading track 27 to transmit the LED. The loading track 27 is installed with a conveyor belt for transmitting the LED. The internal surface of the loading barrel 17 is installed with a weight sensor for sensing the LED. The sensor relies on the weight sensor to sense that the LED enters the feeding barrel 17. The weight sensor sends a feedback signal to the control panel 2. The control panel 2 is provided with a single chip microcomputer to control the conveyor belt to transmit the LED transmitted from the feeding barrel 17 to the feeding track 27. The feeding track 27 has a plurality of guide grooves 32, which are connected to the feeding barrel 17. The LED enters the guide groove 32 from the feeding barrel 17. The guide groove 32 is in the shape of a long strip. A plurality of air extraction ports 28 are installed on the periphery of the feeding track 27. A vibrator 29 is installed at the lower end of the feeding track 27. The vibrator 29 generates a constant periodic vibration on the entire feeding track 27. The feeding track 27 is slightly tilted as a whole, and the LED bounces and moves inside the guide slot 32 by the vibration force brought by the vibration source generated by the vibrator 29. The LED will be arranged in a long strip inside the guide slot 32. The upper end of the feeding track 27 is covered with a plurality of protective sheets 31, and the protective sheets 31 prevent the LED from falling upward from the guide slot 32. A plurality of sensors 30 installed on the upper end of the feeding track 27 are arranged between two adjacent protective sheets 31. The surface of the protective sheet 31 is provided with a plurality of through holes that match and align with the shape of the sensor 30. The end of the sensor 30 extends to the inside of the adjacent through hole, and the sensor 30 will follow the corresponding The inside of the through hole emits rays into the guide groove 32. The inside of the guide groove 32 is smooth. When the rays are irradiated into the inside of the guide groove 32, mirror reflection will occur. When the rays are irradiated into the LED, the effect of mirror reflection will be changed. Feedback is given to the sensor 30 based on the ray reflection. The sensor 30 is used to sense whether the LED is transferred to a position close to the exhaust port 28 on the loading track 27. The exhaust port 28 exhausts the guide groove 32 opened inside the loading track 27. The inside of the guide groove 32 is in a "negative pressure" state. The LED is adsorbed inside the guide groove 32 and will not vibrate and run away, which is convenient for the robot arm of the next process to automatically grab the LED to the next process.

[0035] The above steps are executed cyclically, so that each vacuum suction cup 7 can take turns to suck each LED and grab and place them in turn inside the first straightening turntable 11, the second straightening turntable 20, and the reversing turntable 14, straighten the LED pins, straighten the LED pins, adjust the LED pin spacing and positions, make the two LED pins accurately and fully contact with the two test electrodes 19 respectively, avoid misdetection of LEDs, leakage and the like, and complete accurate power-on test of each LED before feeding and conveying, to ensure that each LED fed out can be powered on and used normally, so that the straightening and testing processes are carried out in parallel with the feeding process, which is suitable for feeding LEDs of various shapes, sizes, models and specifications, and the feeding functions are diversified, so that the processes are integrated and optimized, which is conducive to saving time, speeding up production speed and improving production efficiency.

Claims

1. A high-speed feeding device for LED production, comprising a machine (1), characterized in that: A rotating wheel (4) is arranged in the middle of the upper end of the machine platform (1); the center of the rotating wheel (4) is fixedly connected to a central axis (6); a plurality of electric push rods (9) are fixedly connected around the rotating wheel (4); and the lower ends of the electric push rods (9) are fixedly connected to vacuum suction cups (7); A loading cylinder (17), a test seat (18), a first straightening turntable (11), a second straightening turntable (20) and a reversing turntable (14) are sequentially arranged at the upper end of the machine (1) and adjacent to any one side of the rotating wheel (4); a protrusion (16) is integrally formed at the upper end of the reversing turntable (14); and a pair of test electrodes (19) are installed at the upper end of the test seat (18); The upper end of the first straightening turntable (11) is connected to a plurality of first clamping claws (12) through mechanical transmission, and the inner ends of the first clamping claws (12) are connected to a plurality of first clamping fixtures (13) through mechanical transmission; The second straightening turntable (20) is connected to a plurality of second clamping claws (21) via mechanical transmission, and the inner ends of the second clamping claws (21) are connected to a plurality of second clamping fixtures (22) via mechanical transmission.

2. A high-speed feeding device for LED production as claimed in claim 1, characterized in that: A control panel (2) is installed at any corner of the upper end of the machine platform (1).

3. The high-speed feeding equipment for LED production according to claim 1, characterized in that: The lower end of the central shaft (6) is drivingly connected to a first motor (10), and the lower end of the first motor (10) is fixedly connected to the upper end of the machine platform (1).

4. The high-speed feeding equipment for LED production according to claim 1, characterized in that: The upper end of the electric push rod (9) is provided with a first vacuum pipe opening (5) which is connected to the interior of the adjacent vacuum suction cup (7), and the upper end of the central axis (6) is provided with a second vacuum pipe opening (8), and a hose is connected between the first vacuum pipe opening (5) and the second vacuum pipe opening (8) via a flange.

5. The high-speed feeding equipment for LED production according to claim 1, characterized in that: A feeding rail (25) and a hopper (3) are connected via mechanical transmission at the upper end of the machine platform (1) and adjacent to any side of the rotating wheel (4); an end of the feeding rail (25) away from the rotating wheel (4) is connected via mechanical transmission to a vibration plate (26); the lower end of the vibration plate (26) is fixedly connected to the upper end of the machine platform (1); and a hopper (3) is installed around the rotating wheel (4) and adjacent to any side of the vibration plate (26).

6. The high-speed feeding equipment for LED production according to claim 1, characterized in that: The end of the reversing turntable (14) away from the rotating wheel (4) is connected to a second motor (15) through a synchronous belt transmission, and the lower end of the second motor (15) is fixedly connected to the upper end of the machine platform (1).

7. The high-speed feeding equipment for LED production according to claim 1, characterized in that: The lower end of the second righting turntable (20) is transmission-connected to a third motor (23), the lower end of which is fixedly connected to the upper end of the machine platform (1); the lower end of the first righting turntable (11) is transmission-connected to a fourth motor (24), the lower end of which is fixedly connected to the upper end of the machine platform (1).

8. The high-speed feeding equipment for LED production according to claim 1, characterized in that: A loading track (27) is installed at the upper end of the machine platform (1) and adjacent to one side of the rotating wheel (4), and the loading track (27) is connected to the loading barrel (17) through mechanical transmission.

9. The high-speed feeding equipment for LED production according to claim 8, characterized in that: A plurality of guide grooves (32) are provided inside the feeding track (27); a plurality of protective sheets (31) are provided on the upper end of the feeding track (27); a plurality of sensors (30) mounted on the upper end of the feeding track (27) are provided between two adjacent protective sheets (31); a plurality of through holes that match and align with the shapes of the sensors (30) are provided on the surface of the protective sheets (31); and the ends of the sensors (30) extend into the interiors of the adjacent through holes.

10. The high-speed feeding equipment for LED production according to claim 9, characterized in that: A plurality of air extraction ports (28) are installed on the periphery of the feeding track (27), and a vibrator (29) is installed at the lower end of the feeding track (27).

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