阅读说明：本技术 功率放大器芯片测试系统及测试方法 (Power amplifier chip test system and test method ) 是由 张孝忠 徐辉 张航 黄子明 戴永洪 林存西 于 2021-10-11 设计创作，主要内容包括：本发明公开功率放大器芯片测试系统及测试方法,包括箱体以及固定在箱体内部的隔板,所述隔板将箱体的内部空间隔开形成两个测试腔,所述测试腔的底部固定有放置台,所述放置台的顶端放置有芯片,所述箱体的顶部两侧固定连接有挡板,所述挡板的上方设置有用于封挡测试腔而隔绝外部干扰的第一箱盖机构与第二箱盖机构,通过在箱体的顶部两侧固定设置挡板,挡板的上方设置两个结构相同且对称放置的第一箱盖机构与第二箱盖机构,通过挡板对第一箱盖机构与第二箱盖机构进行限位,进而封挡测试腔而隔绝外部对芯片在测试时的干扰,另外,在打开第一旋转盖和第二旋转盖的同时可通过限位组件带动芯片翻转,进而便于芯片的取出与放置。(The invention discloses a power amplifier chip testing system and a testing method, which comprises a box body and a clapboard fixed in the box body, wherein the clapboard separates the inner space of the box body into two testing cavities, the bottom of the testing cavity is fixed with a placing table, the top end of the placing table is provided with a chip, two sides of the top of the box body are fixedly connected with a baffle plate, a first box cover mechanism and a second box cover mechanism which are used for blocking the testing cavities to isolate external interference are arranged above the baffle plate, the baffle plate is fixedly arranged on two sides of the top of the box body, the first box cover mechanism and the second box cover mechanism which have the same structure and are symmetrically arranged are arranged above the baffle plate, the first box cover mechanism and the second box cover mechanism are limited by the baffle plate, the testing cavities are further blocked to isolate the external interference to the chip during testing, in addition, the first rotating cover and the second rotating cover are opened, and the chip can be driven to turn over by a limiting component, thereby facilitating the taking out and placing of the chip.)

1. Power amplifier chip test system, including box (1) and fix baffle (2) inside box (1), baffle (2) are separated the inside space of box (1) and are formed two test chambers, test chamber's bottom is fixed with places platform (3), chip (4), its characterized in that have been placed to the top of placing platform (3): the test box comprises a box body (1), wherein two sides of the top of the box body (1) are fixedly connected with baffle plates (26), a first box cover mechanism (13) and a second box cover mechanism (14) which are used for blocking a test cavity to isolate external interference are arranged above the baffle plates (26), two sides of the first box cover mechanism (13) and the second box cover mechanism (14) are provided with internal pressure mechanisms, one side of each baffle plate (2) is provided with a driving mechanism which is used for driving the internal pressure mechanisms to move so as to enable the first box cover mechanism (13) and the second box cover mechanism (14) to fold inwards, limiting components which are used for clamping two sides of a chip (4) during folding are arranged on the first box cover mechanism (13) and the second box cover mechanism (14), two ends of the first box cover mechanism (13) and the second box cover mechanism (14) are provided with transverse moving mechanisms which are used for driving the chip (4) to move towards one side, and the limiting components drive the chip (4) to rotate outwards to separate from the test cavity during movement, and the limiting assembly is self-locked after the first box cover mechanism (13) and the second box cover mechanism (14) move to the stacking state.

2. The power amplifier chip test system of claim 1, wherein: the first box cover mechanism (13) and the second box cover mechanism (14) are identical in structure and are symmetrically arranged left and right, the first box cover mechanism (13) and the second box cover mechanism (14) respectively comprise a first rotating cover (15) and a second rotating cover (16), the first rotating cover (15) is hinged to the second rotating cover (16), slopes (17) are arranged at outer end angles of the first rotating cover (15) and the second rotating cover (16), and two fixing plates (18) are fixedly connected to outer end portions of the first rotating cover (15) and the second rotating cover (16).

3. The power amplifier chip test system of claim 1, wherein: the internal pressure mechanism comprises a connecting plate (9), one end of the connecting plate (9) is fixedly connected with a U-shaped plate (10), a second motor (12) is fixedly connected to the inner side wall of the U-shaped plate (10), the output shaft of the second motor (12) is fixedly connected with one end of a push plate (11), and the other end of the push plate (11) is rotatably connected with the U-shaped plate (10).

4. The power amplifier chip test system of claim 3, wherein: actuating mechanism includes two slides (6), it leads to groove (5), two to open in baffle (2) slide (6) are fixed on the outer wall that leads to groove (5) both sides box (1), first motor (7) of fixedly connected with on slide (6) the inside wall of box (1) one side, the two-way threaded rod of output shaft fixedly connected with (8) of first motor (7), two-way threaded rod (8) and connecting plate (9) threaded connection, connecting plate (9) and slide (6) sliding connection.

5. The power amplifier chip test system of claim 2, wherein: the limiting assembly comprises a fixing rod (24), a groove (23) is formed in the bottom of each of the first rotating cover (15) and the second rotating cover (16), the fixing rod (24) is rotatably connected to the inner side wall of the groove (23), and a limiting plate (25) is fixedly connected to one end of the fixing rod (24).

6. The power amplifier chip test system of claim 2, wherein: the outer end of the fixed plate (18) is provided with a movable groove, and a ball (19) is movably embedded in the movable groove.

7. The power amplifier chip test system of claim 2, wherein: the transverse moving mechanism comprises a rotating plate (21), the rotating plate (21) is rotatably connected with a fixed plate (18), a third motor (20) is fixedly connected to the bottom end of the fixed plate (18), an output shaft of the third motor (20) is fixedly connected with the rotating plate (21), and an electric roller (22) is mounted at the bottom end of the rotating plate (21).

8. A method for testing a power amplifier chip using the power amplifier chip testing system as set forth in claim 1, comprising the steps of:

firstly, placing a chip (4) to be tested on a placing table (3) in a testing cavity, and testing the chip (4) on the placing table (3) after the top of the testing cavity is blocked by a first box cover mechanism (13) and a second box cover mechanism (14);

after the test is finished, the driving mechanism drives the internal pressure mechanisms on the two sides to synchronously move inwards, so that the first box cover mechanism (13) or the second box cover mechanism (14) is extruded, the first box cover mechanism (13) or the second box cover mechanism (14) is folded inwards and clamped on the two sides of the lower chip (4) by the limiting assemblies on the two sides;

driving the first box cover mechanism (13) or the second box cover mechanism (14) to move towards the opposite side by the transverse moving mechanism, and driving the chip (4) to rotate outwards by the limiting component to be separated from the test cavity due to the blocking of the partition plate (2) in the moving process;

and fourthly, when the first box cover mechanism (13) or the second box cover mechanism (14) moves to the stacking state, the chip (4) is taken out through self-locking of the transverse moving mechanism.

Technical Field

The invention belongs to the technical field related to chip testing, and particularly relates to a power amplifier chip testing system and a power amplifier chip testing method.

Background

In the chip manufacturing industry, the chip defects need to be detected through performance tests before the chip leaves a factory, so that the quality of the chip is distinguished.

Application number CN202020579208.4 discloses an automatic chip testing device, which comprises a testing machine body provided with a sliding groove along the length direction, and a chip mounting seat arranged on the sliding groove and movably connected with the sliding groove; the testing machine body is provided with a feeding port and a detection port which are communicated with the sliding groove along the vertical direction, and the upper end of the detection port is provided with a chip testing seat; the chip mounting seat is connected with the push rod of the stroke air cylinder, the lower chip testing seat is arranged at the upper end of the chip mounting seat, the lower chip testing seat is provided with a containing port for containing a chip to be tested and a placing port for circumferentially fixing the chip to be tested, when the upper chip testing seat and the lower chip testing seat are closed, the upper chip testing seat is used for testing the chip to be tested.

The technical solution proposed by the above document has the following problems: the chip to be tested faces outwards in the detection process, certain influence is easily caused to the test under the external interference, in addition, the chip is not taken out and placed automatically enough, the convenience is poor, certain clamping force is provided for the chip, and the chip is easy to damage.

Disclosure of Invention

The invention aims to provide a power amplifier chip test system and a test method, which are used for solving the problems of external interference, inconvenience in taking and placing and clamping chips which are easy to damage in the background technology.

In order to achieve the purpose, the invention provides the following technical scheme: the power amplifier chip testing system comprises a box body and a partition board fixed in the box body, wherein the partition board separates the internal space of the box body to form two testing cavities, a placing table is fixed at the bottom of each testing cavity, a chip is placed at the top end of the placing table, two sides of the top of the box body are fixedly connected with a baffle, a first box cover mechanism and a second box cover mechanism which are used for blocking the testing cavities and isolating external interference are arranged above the baffle, internal pressure mechanisms are arranged on two sides of the first box cover mechanism and the second box cover mechanism, a driving mechanism used for driving the internal pressure mechanisms to move and enabling the first box cover mechanism and the second box cover mechanism to be folded inwards is arranged on one side of the partition board, limiting assemblies used for being clamped on two sides of the chip when being folded are arranged on the first box cover mechanism and the second box cover mechanism, and transverse moving mechanisms used for driving the chip to move towards one side are arranged at two ends of the first box cover mechanism and the second box cover mechanism, and in the moving process, the limiting component drives the chip to rotate outwards to be separated from the test cavity, and the limiting component is self-locked after the first box cover mechanism and the second box cover mechanism move to the stacking state.

Preferably, the first box cover mechanism and the second box cover mechanism are identical in structure and are symmetrically arranged in the left and right direction, the first box cover mechanism and the second box cover mechanism respectively comprise a first rotating cover and a second rotating cover, the first rotating cover is hinged to the second rotating cover, slopes are arranged at the outer end corners of the first rotating cover and the second rotating cover, and two fixing plates are fixedly connected to the outer end portions of the first rotating cover and the second rotating cover.

Preferably, the internal pressure mechanism comprises a connecting plate, one end of the connecting plate is fixedly connected with a U-shaped plate, a second motor is fixedly connected to the inner side wall of the U-shaped plate, an output shaft of the second motor is fixedly connected with one end of a push plate, and the other end of the push plate is rotatably connected with the U-shaped plate.

Preferably, actuating mechanism includes two slides, set up logical groove in the baffle, two the slide is fixed on the outer wall of leading to the groove both sides box, the first motor of fixedly connected with on the slide inside wall of box one side, the two-way threaded rod of output shaft fixedly connected with of first motor, two-way threaded rod and connecting plate threaded connection, connecting plate and slide sliding connection.

Preferably, the limiting assembly comprises a fixing rod, the bottoms of the first rotary cover and the second rotary cover are provided with grooves, the inner side wall of each groove is rotatably connected with the fixing rod, and one end of each fixing rod is fixedly connected with a limiting plate.

Preferably, the outer end of the fixing plate is provided with a movable groove, and a ball is movably embedded in the movable groove.

Preferably, the traversing mechanism comprises a rotating plate, the rotating plate is rotatably connected with a fixed plate, a third motor is fixedly connected to the bottom end of the fixed plate, an output shaft of the third motor is fixedly connected with the rotating plate, and an electric roller is mounted at the bottom end of the rotating plate.

The chip testing method comprises the following steps:

the method comprises the following steps: placing a chip to be tested on a placing table in a testing cavity, and testing the chip on the placing table after the top of the testing cavity is blocked by a first box cover mechanism and a second box cover mechanism;

step two: after the test is finished, the driving mechanism drives the internal pressure mechanisms on the two sides to synchronously move inwards, so that the first box cover mechanism or the second box cover mechanism is extruded, the first box cover mechanism or the second box cover mechanism is folded inwards and clamped on the two sides of the chip below by the limiting assemblies on the two sides;

step three: the transverse moving mechanism drives the first box cover mechanism or the second box cover mechanism to move towards the opposite side, and in the moving process, the limiting assembly drives the chip to rotate outwards to be separated from the test cavity due to the blocking of the partition plate;

step four: when the first box cover mechanism or the second box cover mechanism moves to the stacking state, the chip is taken out through self-locking of the transverse moving mechanism.

Compared with the prior chip testing technology, the invention provides a power amplifier chip testing system and a testing method, which have the following beneficial effects:

1. according to the invention, the baffle plates are fixedly arranged on two sides of the top of the box body, the first box cover mechanism and the second box cover mechanism which are identical in structure and are symmetrically arranged are arranged above the baffle plates, the first box cover mechanism and the second box cover mechanism are limited by the baffle plates, so that the test cavity is sealed and the interference of the outside on a chip during testing is isolated, in addition, the chip can be driven to overturn by the limiting assembly when the first rotary cover and the second rotary cover are opened, and the chip can be conveniently taken out and placed;

2. according to the invention, the first rotating cover and the second rotating cover are extruded by the internal pressure mechanism, so that the first rotating cover and the second rotating cover rotate to a certain angle according to the hinge point, when the fixed plate is parallel to the top surface of the box body, the balls are in rolling contact with the inner side of the push plate, the friction force can be reduced, and the two limiting plates are positioned at the two sides of the chip and do not have inward clamping force on the chip, so that the chip can be protected, and the extrusion damage caused when the chip is turned over can be avoided;

3. according to the invention, the third motor on the transverse moving mechanism drives the rotating plate and the electric roller to rotate and then close, the first rotating cover and the second rotating cover are locked and fixed, the first rotating cover and the second rotating cover are prevented from moving back and forth, the electric roller can be unlocked from being locked in the front and back direction by opening the reverse rotation of the third motor, and the transverse moving of the first rotating cover and the second rotating cover is facilitated.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention without limiting the invention in which:

FIG. 1 is a schematic view of an overall structure of a chip testing apparatus according to a first state of the present invention;

FIG. 2 is a schematic side view of a cross-sectional structure of a chip testing device according to the present invention;

FIG. 3 is a schematic diagram of a left side elevational cross-sectional structure of the chip testing apparatus according to the present invention;

FIG. 4 is a schematic diagram of a right side elevation cross-sectional structure of the chip testing apparatus according to the present invention;

FIG. 5 is a schematic diagram of a push plate structure according to the present invention;

FIG. 6 is a schematic top view of the first and second rotary covers according to the present invention;

FIG. 7 is a schematic bottom view of the first and second rotary covers according to the present invention;

FIG. 8 is a schematic cross-sectional view of a fixing plate according to the present invention;

FIG. 9 is a cross-sectional view of a second state of the chip testing device according to the present invention;

FIG. 10 is a schematic view of an overall structure of a chip testing apparatus according to a third embodiment of the present invention;

in the figure: 1. a box body; 2. a partition plate; 3. a placing table; 4. a chip; 5. a through groove; 6. a slide base; 7. a first motor; 8. a bidirectional threaded rod; 9. a connecting plate; 10. a U-shaped plate; 11. pushing the plate; 12. a second motor; 13. a first lid mechanism; 14. a second lid mechanism; 15. a first rotary cover; 16. a second rotary cover; 17. a slope; 18. a fixing plate; 19. a ball bearing; 20. a third motor; 21. a rotating plate; 22. an electric roller; 23. a groove; 24. fixing the rod; 25. a limiting plate; 26. and a baffle plate.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1-10, the present invention provides a technical solution: the power amplifier chip testing system comprises a box body 1 and a partition plate 2 fixed inside the box body 1. The baffle 2 separates the inner space of box 1 and forms two test chambers, and the bottom in test chamber is fixed with places platform 3, and chip 4 has been placed on the top of placing platform 3, and the top both sides fixedly connected with baffle 26 of box 1. The position of the baffle 26 is as shown in fig. 1, 3 and 4, a first cover mechanism 13 and a second cover mechanism 14 for blocking the test chamber to isolate external interference are arranged above the baffle 26, the first cover mechanism 13 and the second cover mechanism 14 have the same structure and are arranged symmetrically left and right, the first cover mechanism 13 and the second cover mechanism 14 both comprise a first rotating cover 15 and a second rotating cover 16, the first rotating cover 15 is hinged with the second rotating cover 16, the hinged part of the first rotating cover 15 and the second rotating cover 16 and the shape of the two are as shown in fig. 7, the outer end corners of the first rotating cover 15 and the second rotating cover 16 are both provided with slopes 17, when the first cover mechanism 13 and the second cover mechanism 14 move horizontally towards each other, the first cover mechanism 13 and the second cover mechanism 14 can be overlapped with each other through the slopes 17, so as to open the test chamber, the outer end parts of the first rotating cover 15 and the second rotating cover 16 are both fixedly connected with two fixing plates 18, the outer end of the fixed plate 18 is provided with a movable groove, and the ball 19 is movably embedded in the movable groove, so that the friction force is reduced, and the horizontal movement of the first rotating cover 15 or the second rotating cover 16 is facilitated.

It should be noted that, the internal pressure mechanisms are disposed on two sides of the first box cover mechanism 13 and the second box cover mechanism 14, each internal pressure mechanism includes a connecting plate 9, one end of each connecting plate 9 is fixedly connected with a U-shaped plate 10, a second motor 12 is fixedly connected to the inner side wall of each U-shaped plate 10, an output shaft of each second motor 12 is fixedly connected to one end of each push plate 11, the other end of each push plate 11 is rotatably connected to the corresponding U-shaped plate 10, the shape of each push plate 11 is as shown in fig. 5, the push plates 11 can be driven by the second motors 12, the output shafts of the second motors 12 drive the push plates 11 to rotate 180 degrees, and accordingly, the first rotating cover 15 or the second rotating cover 16 can be correspondingly extruded in the process of moving towards the inside.

It is worth understanding that, one side of baffle 2 is equipped with and is used for driving about the internal pressure mechanism motion and makes the actuating mechanism of inwards folding up of first case lid mechanism 13 and second case lid mechanism 14, actuating mechanism includes two slides 6, logical groove 5 has been seted up in the baffle 2, two slides 6 are fixed on the outer wall of logical groove 5 both sides box 1, fixedly connected with first motor 7 on the 6 inside walls of slide of box 1 one side, the output shaft fixedly connected with two-way threaded rod 8 of first motor 7, two-way threaded rod 8 and connecting plate 9 threaded connection, connecting plate 9 and slide 6 sliding connection, when the output shaft of first motor 7 drives two-way threaded rod 8 and rotates, through two-way threaded rod 8 and connecting plate 9 screw thread relation, simultaneously under connecting plate 9 and slide 6 slip spacing, both sides make connecting plate 9 move to the inboard in step.

It should be noted that, the first box cover mechanism 13 and the second box cover mechanism 14 are respectively provided with a limiting component for wrapping and clamping two sides of the chip 4 when being folded, the limiting component comprises a fixing rod 24, the bottom of the first rotating cover 15 and the bottom of the second rotating cover 16 are respectively provided with a groove 23, the inner side wall of each groove 23 is rotatably connected with the fixing rod 24, one end of each fixing rod 24 is fixedly connected with a limiting plate 25, the shape of each limiting plate 25 is as shown in fig. 7, after the first box cover mechanism 13 and the second box cover mechanism 14 are folded inwards, the limiting components below can be driven to be drawn close towards the inner side, the limiting plates 25 of the limiting components are wrapped and clamped on two sides of the chip 4 until the limiting plates 25 of the limiting components are folded, and then when the first box cover mechanism 13 and the second box cover mechanism 14 move horizontally, the chip 4 can be driven to move synchronously by the limiting plates 25.

It is worth noting that the two ends of the first box cover mechanism 13 and the second box cover mechanism 14 are provided with a transverse moving mechanism for driving the chip 4 to move towards one side, wherein the transverse moving mechanism comprises a rotating plate 21, the rotating plate 21 is rotatably connected with a fixed plate 18, the bottom end of the fixed plate 18 is fixedly connected with a third motor 20, an output shaft of the third motor 20 is fixedly connected with the rotating plate 21, the bottom end of the rotating plate 21 is provided with an electric roller 22, in the moving process, the limiting component drives the chip 4 to rotate outwards to separate from the test cavity, the limiting component is self-locked after the first box cover mechanism 13 and the second box cover mechanism 14 move to the stacking state, when the first box cover mechanism 13 and the second box cover mechanism 14 move horizontally, the chip 4 is driven by a limiting plate 25 to move synchronously, and in the moving process, the limiting component drives the chip 4 to rotate outwards due to the blocking of the partition plate 2.

The chip testing method comprises the following steps:

the method comprises the following steps: placing a chip 4 to be tested on a placing table 3 in a testing cavity, and testing the chip 4 on the placing table 3 after the top of the testing cavity is blocked by a first box cover mechanism 13 and a second box cover mechanism 14;

step two: after the test is finished, the driving mechanism drives the internal pressure mechanisms on the two sides to synchronously move inwards, so that the first box cover mechanism 13 or the second box cover mechanism 14 is extruded, the first box cover mechanism 13 or the second box cover mechanism 14 is folded inwards and clamped on the two sides of the lower chip 4 by the limiting assemblies on the two sides;

step three: the transverse moving mechanism drives the first box cover mechanism 13 or the second box cover mechanism 14 to move towards the opposite side, and in the moving process, the spacing component drives the chip 4 to rotate outwards to be separated from the test cavity due to the blocking of the partition plate 2;

step four: when the first cover mechanism 13 or the second cover mechanism 14 moves to the stacking state, the chip 4 is taken out by self-locking of the transverse moving mechanism.

The working principle and the using process of the invention are as follows: as shown in fig. 1-8, the device is in an initial state. In this state, the motorized roller 22 is blocked by the blocking plate 26, so that the first rotary cover 15 and the second rotary cover 16 are prevented from sliding and deviating from the test chamber below.

When the chip 4 in the test cavity below the first box cover mechanism 13 finishes testing, the first motor 7 is started, the first motor 7 drives the bidirectional threaded rod 8 to rotate through the output shaft, then the two connecting plates 9 are driven to move towards the inner side, and the two connecting plates 9 drive the two push plates 11 to move towards the inner side through the U-shaped plates 10. The two push plates 11 respectively push the fixing plates 18 on both sides of the first rotary cover 15 and the second rotary cover 16 to move inwards, so that the first rotary cover 15 and the second rotary cover 16 rotate through the hinge shaft and move inwards at the top end of the box body 1 through the electric roller 22, meanwhile, the first rotary cover 15 and the second rotary cover 16 drive the limiting plates 25 to move through the fixing rods 24, when the first rotary cover 15 and the second rotary cover 16 rotate to a certain angle, the first motor 7 is turned off, the device keeps the second state as shown in fig. 9, the fixing plates 18 are parallel to the top surface of the box body 1 in the figure, the balls 19 are in rolling contact with the inner sides of the push plates 11, and the two limiting plates 25 are located on both sides of the chip 4, are not clamped, only surround the chip 4, and are not in contact with the chip 4.

Then, the third motor 20 is started to drive the rotating plate 21 and the electric roller 22 to rotate by 90 degrees and then to be closed, then the electric roller 22 is started to drive the first rotating cover 15 and the second rotating cover 16 to move towards the second cover mechanism 14, the first cover mechanism 13 can be moved to the top end of the second cover mechanism 14 through the slope 17 on the second cover mechanism 14, in the moving process, the first rotating cover 15 and the second rotating cover 16 can drive the fixing rod 24 to move together, but the fixing rod 24 is blocked by the partition plate 2 when moving, so that the fixing rod 24 can rotate around the hinge shaft of the first rotating cover 15 and the second rotating cover 16, the chip 4 is further driven to rotate through the limiting plate 25, when the first rotating cover 15 and the second rotating cover 16 move to a certain distance, the electric roller 22 is closed, and the state at this time is shown in fig. 10. The first rotary cover 15 and the second rotary cover 16 in the first cover mechanism 13 are positioned on top of the first rotary cover 15 and the second rotary cover 16 in the second cover mechanism 14, and the chip 4 is rotated out of the test chamber. At this time, the device keeps the third state as shown in fig. 10, the third motor 20 is started to drive the rotating plate 21 and the electric roller 22 to rotate for 90 degrees and then be closed, the first rotating cover 15 and the second rotating cover 16 are prevented from moving back and forth, then the chip 4 is taken out, the next chip 4 to be detected is placed at the position (between the two limiting plates 25), the third motor 20 is started again to drive the rotating plate 21 and the electric roller 22 to rotate for 90 degrees and then be closed, and the electric roller 22 is enabled to cancel the locking in the front-back direction. The operation is reversed to restore the apparatus to the initial state, and the chip 4 is also placed on the placing table 3.

If the chip 4 in the test cavity below the second cover mechanism 14 needs to be taken out, the second motor 12 needs to be started in advance, and the second motor 12 drives the push plate 11 to rotate 180 degrees through the output shaft and then stops. The other operations are the same as the above principle.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.