Lead frame surface mounting device equipmentTechnical Field
The invention relates to the technical field of lead frames, in particular to lead frame surface mount device equipment.
Background
Lead frames (leadframes), also known as LEADFRAME, conductor frame (emphasizing conductive functions) or Pin frames (emphasizing Pin functions), are a generic term in the fields of electronics engineering and electronics packaging, referring to metal frames used to support and connect the pins of electronic chips. It is the base material of semiconductor packages in which the finished chip has to be removed from the dicing film and placed in a set position on a leadframe or package substrate (baseboard) for the next wire bonding or other interconnection process. This step is actually a mounting technology, and the leadframe surface mount device is one of the key devices for implementing this technology.
The utility model discloses a lead frame for packaging semiconductor device, including the intermediate frame, the bottom frame, the top layer frame, first pin and second pin are located the intermediate frame, the bottom frame is located to the third pin, the top layer frame is located to the fourth pin, first pin and second pin all have the welded plate, the welded plate all is equipped with first bump down, the third pin corresponds the backup pad that the welded plate was equipped with, be used for setting up the chip between the bottom surface of backup pad upper surface and first bump, the fourth pin corresponds the welded plate and is equipped with the clamp plate, the clamp plate bottom corresponds first bump and all is equipped with the second bump down, be used for setting up the chip between welded plate upper surface and the second bump bottom, bottom frame and intermediate frame and top layer frame are by supreme equipment that overlaps down, top layer frame and intermediate frame and bottom frame all have a plurality of rectangular chamber that correspond from top to bottom, rectangular intracavity portion forms a plurality of semiconductor device encapsulation regions along length direction array, the semiconductor device encapsulation of multichip of being convenient for has higher production efficiency.
Based on the above patent search and the device in the prior art, it is found that the existing lead frame assembly is generally arranged in an array form, when the chip is mounted, the assembly needs to be accurately arranged on the positioning disc, then, the grabbing mechanical arm accurately grabs the chip from the substrate and stably mounts the chip on the island of the lead frame, once the mounting is completed, the old lead frame assembly needs to be replaced with a new one to perform the next round of operation, the series of steps are quite complex and time-consuming, not only increasing the difficulty of manual operation, but also limiting the efficiency of the automatic production flow, simplifying the operation flow, and having important significance for improving the overall production efficiency, so we make an improvement on the lead frame surface mount device.
Disclosure of Invention
The invention aims at arranging the existing lead frame components in an array mode generally, accurately arranging the components on a positioning disc during chip mounting, accurately grabbing chips from a substrate by a grabbing mechanical arm, stably mounting the chips on a base island of a lead frame, replacing the old lead frame components with new lead frame components once mounting is completed for next round of operation, and the series of steps are quite complicated and time-consuming, thereby not only increasing the difficulty of manual operation, but also limiting the efficiency of an automatic production flow.
In order to achieve the above purpose, the invention provides the device which is inserted into the positioning opening when the intermittent driving part drives the pushing block to reciprocate, and the frame edge is driven to move forwards by pushing the positioning opening, so that continuous feeding is realized, the difficulty of manual operation is reduced, and the efficiency of an automatic production process is improved, so that the problems are solved.
The application is specifically as follows:
The utility model provides a lead frame surface mounting device equipment, is including the lead frame that is banded and distributes, the lead frame includes the frame limit, the inside of frame limit is provided with the base island, the inboard equipartition of frame limit is fixed with multiunit connection pin, it is fixed through blank pin between base island and the frame limit, the locating opening has been seted up to the bilateral symmetry of frame limit, still includes mounting equipment, mounting equipment includes continuous conveying subassembly and pickup assembly, and continuous conveying subassembly includes the brace table, the lead frame sets up on the brace table, the bottom of brace table is fixed with the supporting leg, the bilateral symmetry of brace table is fixed with first support frame, one side symmetry sliding connection that first support frame is close to each other has the ejector pad, be provided with intermittent drive part between ejector pad and the brace table.
As a preferable technical scheme of the application, an overflow preventing groove is arranged at the edge of the top of the base island.
As a preferable technical scheme of the application, the intermittent driving part comprises second supporting frames symmetrically fixed at one end of a supporting table, the bottoms of the two second supporting frames are connected with a transmission rod in a common rotation mode, a second straight gear is fixed on the surface of the transmission rod, a second single-head motor is fixed at the bottom of the supporting table, a first straight gear is fixed at the output end of the second single-head motor, and the first straight gear is meshed with the second straight gear.
As the preferable technical scheme of the application, two ends of one side of the two second support frames, which are far away from each other, are respectively and symmetrically connected with a first single-head belt pulley and a second single-head belt pulley in a rotating way, the second single-head belt pulley is fixed with two ends of a transmission rod, the two second single-head belt pulleys are in transmission connection through a first tooth-shaped transmission belt, the tops of one side of the two second support frames, which are close to each other, are rotatably connected with a rocker, and the rocker is fixed with the first single-head belt pulley.
As the preferable technical scheme of the application, a first adjusting rod is arranged between two rocking rods, two ends of the first adjusting rod are respectively and slidably connected in the rocking rods, two ends of the surface of the first adjusting rod are symmetrically fixed with connecting rings, the surface of each connecting ring is rotationally connected with a rotating ring, a push rod is fixed on the outer side of each rotating ring, one end, far away from each rotating ring, of each push rod is rotationally connected with a first connecting plate, one end of each first connecting plate is fixedly provided with a mounting shell, each push block is rotationally connected in the mounting shell, and a stroke adjusting part is arranged between each first adjusting rod and each rocking rod.
As a preferable technical scheme of the application, one side of the first connecting plate is fixed with a sliding block, one side of the two first supporting frames, which are close to each other, is fixed with a guide rail, and the sliding block is connected to the surface of the guide rail in a sliding way.
As the preferable technical scheme of the application, a round angle is formed at the bottom of the push block and positioned at one side close to the rotating ring, a return spring is arranged between the top of the push block and the mounting shell, and a stop block is fixed at the top of the push block and positioned at one side far away from the rotating ring.
As a preferable technical scheme of the application, the stroke adjusting component comprises a first single-head motor fixed on one side of a first adjusting rod, nuts are symmetrically and rotatably connected to two ends of the inner side of the first adjusting rod, a third single-head belt wheel is fixed on the outer side of each nut, a double-head belt wheel is rotatably connected to the inner side of each first single-head motor and positioned between two nuts, the double-head belt wheel is fixed with the output end of each first single-head motor, the double-head belt wheel is in transmission connection with two third single-head belt wheels through second toothed transmission belts, a second threaded rod is fixed in the rocker, and the second threaded rod is in threaded connection with the inner side of each nut.
According to the technical scheme, the top of the supporting table is symmetrically and slidingly connected with the limiting plate, sliding holes are formed in the supporting table and located at the positions of the two ends of the limiting plate, second connecting plates are fixedly arranged at the two ends of the limiting plate and slidingly connected in the sliding holes, second adjusting rods are jointly fixed at the bottoms of the two second connecting plates, fixing rods are symmetrically fixed at the bottoms of the supporting table, the second adjusting rods are located at the positions between the two fixing rods, guide rods are symmetrically fixed between the two fixing rods, two ends of the second adjusting rods are slidingly connected with the guide rods, a double-head motor is fixed at the bottom of the supporting table, first threaded rods are fixed at the two output ends of the double-head motor, the threaded directions of the threads of the two first threaded rods are opposite, and the two first threaded rods are respectively in threaded connection with the second adjusting rods.
According to the preferred technical scheme, the picking assembly comprises a supporting table fixed on one side of the supporting table, a third single-head motor is fixed at the bottom of the supporting table, an outer shell is fixed on the upper surface of the supporting table, a third straight gear and a fourth straight gear are rotatably connected in the outer shell, the third straight gear is meshed with the fourth straight gear, the output end of the third single-head motor is fixed with the fourth straight gear, an electric telescopic seat is rotatably connected to the top of the outer shell, the electric telescopic seat is fixed with the third straight gear, a rocker arm is fixed at the top of the electric telescopic seat, a connecting shaft is fixed at the bottom of one end, far away from the electric telescopic seat, of the rocker arm, and a sucker is arranged at the bottom of the connecting shaft.
Compared with the prior art, the invention has the beneficial effects that:
In the scheme of the application:
1. In order to solve the problem that a grabbing mechanical arm in the prior art can accurately grab chips from a substrate and stably attach the chips to a base island of a lead frame. Once one round of mounting is completed, the old leadframe assemblies need to be replaced with new ones for the next round of operation. The series of steps are quite complex and time-consuming, not only increases the difficulty of manual operation, but also limits the efficiency of an automatic production process, and the application inserts into the positioning opening when the intermittent driving part is arranged to drive the pushing block to reciprocate, and drives the frame edge to move forwards by pushing the positioning opening, thereby realizing continuous feeding, being beneficial to reducing the difficulty of manual operation and improving the efficiency of the automatic production process;
2. The first single-head motor is arranged to drive the double-head belt pulley to rotate, the double-head belt pulley drives the third single-head belt pulley and the nut to rotate through the second tooth-shaped transmission belt, and the nut is in threaded connection with the second threaded rod during rotation, so that the first adjusting rod is driven to move along the axis direction of the second threaded rod, the distance from the first adjusting rod to the first single-head belt pulley is adjusted, the movement stroke of the pushing block is adjusted, the use effect of equipment is improved, and the problem that the feeding stroke is inconvenient to adjust in the prior art is solved;
3. the double-end motor through setting up rotates and drives first threaded rod and rotate, and first threaded rod drives the second when rotating and adjusts the pole and be close to each other or keep away from the motion to adjust the interval between two limiting plates, realized that equipment can adapt to the lead frame of different width, further increase the result of use of equipment, solved the problem of the lead frame of different width of being inconvenient for adaptation among the prior art.
Drawings
Fig. 1 is a schematic structural diagram of a lead frame provided by the present application;
fig. 2 is a schematic structural diagram of a mounting apparatus according to the present application;
FIG. 3 is a schematic view of the bottom structure of the support table according to the present application;
FIG. 4 is a schematic view of the internal structure of the rocker provided by the application;
FIG. 5 is a schematic view of a part of the stroke adjustment member according to the present application;
FIG. 6 is a schematic view of a partial structure of an intermittent drive unit according to the present application;
FIG. 7 is a schematic view of the enlarged partial structure of FIG. 6 according to the present application;
FIG. 8 is a schematic view of the internal structure of the mounting shell provided by the present application;
Fig. 9 is a schematic structural diagram of a pickup assembly according to the present application.
The figures indicate:
1. A frame edge; 2, positioning the port; 3, a base island; 4, an anti-overflow groove, 5, a connecting pin, 6, a first supporting table, 7, a first supporting frame, 8, a press roller, 9, a stop block, 10, a first single-head belt wheel, 11, a first toothed belt wheel, 12, a second single-head belt wheel, 13, a guide rail, 14, a second supporting frame, 15, a push rod, 16, a rocker, 17, a first single-head motor, 18, a first adjusting rod, 19, a supporting leg, 20, a fixed rod, 21, a guide rod, 22, a second adjusting rod, 23, a first, 24, a double-head motor, 25, a sliding hole, 26, a second single-head motor, 27, a first straight gear, 28, a second straight gear, 29, a transmission rod, 30, a second straight gear, 31, a nut, 32, a third single-head belt wheel, 33, a second belt wheel, 34, a double-head belt wheel, 35, a first connecting plate, 36, a slide block, 37, a mounting shell, 38, a push block, 39, a connecting ring, 40, a rotating ring, 41, a reset spring, 42, a third single-head motor, 43, a third straight gear, 44, a fourth gear, a housing, 45, a fourth gear, a straight gear, a 45, a second straight gear, a toothed shaft, a 50, a blank support plate, a blank, a limit plate, a 50, a guide plate, a blank holder, a drive plate, a drive shaft, and 50.
Detailed Description
In order that those skilled in the art will better understand the present invention, a technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in which it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present invention without making any inventive effort, shall fall within the scope of the present invention.
As described in the background, the conventional lead frame assemblies are generally arranged in an array, and the assemblies need to be precisely mounted on the positioning plate when the chip is mounted. Then, the gripper arm can accurately grip the chip from the substrate and stably attach the chip to the base island of the lead frame. Once one round of mounting is completed, the old leadframe assemblies need to be replaced with new ones for the next round of operation. The series of steps are quite complex and time-consuming, not only increase the difficulty of manual operation, but also limit the efficiency of the automatic production process.
In order to solve the technical problem, the invention provides lead frame surface mounting device equipment, which is applied to lead frame surface mounting.
Example 1
Referring to figures 1-9 of the drawings,
The lead frame comprises lead frames distributed in a belt mode, a plurality of lead frames are connected end to form a whole in production, a belt type lead frame assembly is formed, continuous feeding is facilitated in mounting, the lead frame comprises a frame edge 1, a base island 3 is arranged in the frame edge 1, the surface of the base island 3 is used for mounting chips, a plurality of groups of connecting pins 5 are uniformly distributed and fixed on the inner side of the frame edge 1, the base island 3 and the frame edge 1 are fixed through blank pins 50, positioning ports 2 are symmetrically formed on two sides of the frame edge 1 and used for positioning the frame edge 1, the lead frame assembly further comprises mounting equipment, the mounting equipment comprises a continuous conveying assembly and a picking assembly, the picking assembly is used for grabbing chips on a substrate, the lead frame is conveyed to a designated position through the continuous conveying assembly, the picking assembly comprises a supporting table 53 fixed on one side of the supporting table 6, a third single-head motor 42 is fixed on the bottom of the supporting table 53, an outer shell 45 is fixed on the upper surface of the supporting table 53, a third spur gear 43 and a fourth spur gear 44 are rotatably connected to the inner part of the outer shell 45, the third spur gear 43 is meshed with the fourth spur gear 44, the output end of a third single-head motor 42 is fixed with the fourth spur gear 44, the top of the outer shell 45 is rotatably connected with an electric telescopic seat 46, the electric telescopic seat 46 is fixed with the third spur gear 43, a rocker arm 47 is fixed on the top of the electric telescopic seat 46, a connecting shaft 48 is fixed on the bottom of one end of the rocker arm 47 far away from the electric telescopic seat 46, a sucker 49 is arranged on the bottom of the connecting shaft 48, specifically, the fourth spur gear 44 is driven to rotate by the third single-head motor 42, the third spur gear 43 is driven to rotate by the fourth spur gear 44 meshed with the third spur gear 43, so as to drive the sucker 49 to rotate to the right above a substrate, the sucker 49 is driven to move up and down by the electric telescopic seat 46, then the chip on the substrate is grabbed and attached to the base island 3;
A press roller 8 is symmetrically and rotationally connected between the two first support frames 7, and the surface of the press roller 8 is made of rubber;
The continuous conveying assembly comprises a supporting table 6, a lead frame is arranged on the supporting table 6, supporting legs 19 are fixed at the bottom of the supporting table 6, first supporting frames 7 are symmetrically fixed on two sides of the supporting table 6, pushing blocks 38 are symmetrically and slidingly connected to one sides of the first supporting frames 7, which are close to each other, intermittent driving components are arranged between the pushing blocks 38 and the supporting table 6, and particularly, the intermittent driving components are used for driving the pushing blocks 38 to reciprocate and then to be inserted into the positioning ports 2, and the frame edges 1 are driven to move forwards by pushing the positioning ports 2, so that continuous feeding is realized, the difficulty of manual operation is reduced, and the efficiency of an automatic production process is improved;
The edge of the top of the base island 3 is provided with an anti-overflow groove 4, and when a chip is mounted, excessive glue can flow into the anti-overflow groove 4, so that the glue overflow is reduced, and the packaging quality is improved;
The intermittent driving part comprises second supporting frames 14 symmetrically fixed at one end of the supporting table 6, the bottoms of the two second supporting frames 14 are jointly connected with a transmission rod 29 in a rotating mode, a second straight gear 28 is fixed on the surface of the transmission rod 29, a second single-head motor 26 is fixed at the bottom of the supporting table 6, a first straight gear 27 is fixed at the output end of the second single-head motor 26, the first straight gear 27 is meshed with the second straight gear 28, specifically, the first straight gear 27 is driven to rotate through rotation of the second single-head motor 26, the second straight gear 28 is driven to rotate when the first straight gear 27 rotates, and the transmission rod 29 is driven to rotate through the second straight gear 28;
The two ends of one side, far away from each other, of the two second support frames 14 are respectively and symmetrically connected with a first single-head belt pulley 10 and a second single-head belt pulley 12 in a rotating way, the second single-head belt pulley 12 is fixed with the two ends of a transmission rod 29, the two second single-head belt pulleys 12 are in transmission connection through a first toothed transmission belt 11, the tops of one side, close to each other, of the two second support frames 14 are rotatably connected with a rocker 16, the rocker 16 is fixed with the first single-head belt pulley 10, and specifically, the transmission rod 29 drives the second single-head belt pulley 12 to rotate when rotating, the second single-head belt pulley 12 drives the first single-head belt pulley 10 to rotate through the first toothed transmission belt 11, and the rocker 16 is driven to rotate through the first single-head belt pulley 10;
A first adjusting rod 18 is arranged between the two rocking rods 16, two ends of the first adjusting rod 18 are respectively and slidably connected in the rocking rods 16, two ends of the surface of the first adjusting rod 18 are symmetrically and fixedly provided with connecting rings 39, the surface of each connecting ring 39 is rotationally connected with a rotating ring 40, the outer side of each rotating ring 40 is fixedly provided with a push rod 15, one end of each push rod 15 far away from each rotating ring 40 is rotationally connected with a first connecting plate 35, one end of each first connecting plate 35 is fixedly provided with a mounting shell 37, each push block 38 is rotationally connected in each mounting shell 37, a stroke adjusting component is arranged between each first adjusting rod 18 and each rocking rod 16 and is used for adjusting the motion stroke of each push block 38 so as to enable equipment to adapt to lead frames of different types, in particular, the rocking rods 16 drive the first adjusting rod 18 to rotate when rotating, the push rods 15 are pushed by the connecting rings 39 and the rotating rings 40, and the push rods 15 drive the push blocks 38 to reciprocate through the first connecting plates 35 and the mounting shells 37 when rotating;
A sliding block 36 is fixed on one side of the first connecting plate 35, a guide rail 13 is fixed on one side, close to each other, of the two first supporting frames 7, the sliding block 36 is slidably connected to the surface of the guide rail 13, and specifically, the sliding block 36 is slidably connected to the surface of the guide rail 13 for guiding and limiting the first connecting plate 35, the mounting shell 37 and the pushing block 38, so that the running stability of equipment is improved;
The bottom of ejector pad 38 and lie in one side that is close to swivel becket 40 and have seted up the fillet, be convenient for ejector pad 38 break away from the inside of locating hole 2 when the backward movement through the setting of fillet, be provided with reset spring 41 between ejector pad 38's top and the installation shell 37, one side that swivel becket 40 was kept away from to installation shell 37 and lie in ejector pad 38's top is fixed with dog 9, specifically, when ejector pad 38 promotes locating hole 2 forward, carries out spacingly to ejector pad 38 through dog 9, is used for driving ejector pad 38 through reset spring 41 and resets, improves the stability of equipment operation.
Example 2
Further optimization of a leadframe surface mount device apparatus is provided in accordance with embodiment 1, and in particular, as shown in figures 2-5,
The stroke adjusting component comprises a first single-head motor 17 fixed at one side of a first adjusting rod 18, two ends of the inner side of the first adjusting rod 18 are symmetrically and rotatably connected with nuts 31, a third single-head belt pulley 32 is fixed at the outer side of the nuts 31, a double-head belt pulley 34 is rotatably connected at the position, which is positioned between the two nuts 31, of the inner side of the first single-head motor 17, the double-head belt pulley 34 is fixed with the output end of the first single-head motor 17, the double-head belt pulley 34 is respectively in transmission connection with the two third single-head belt pulleys 32 through a second toothed transmission belt 33, a second threaded rod 30 is fixed at the inner side of a rocker 16, the second threaded rod 30 is in threaded connection with the inner side of the nuts 31, specifically, the double-head belt pulley 34 drives the third single-head belt pulley 32 and the nuts 31 to rotate through the second toothed transmission belt 33, the nuts 31 are in threaded connection with the second threaded rod 30 during rotation, so that the first adjusting rod 18 is driven to move along the axis direction of the second threaded rod 30, the distance between the first adjusting rod 18 and the first single-head pulley 10 is adjusted, the movement of a push block 38 is further, the practical head band device is facilitated to be increased,
Example 3
Further optimization of a leadframe surface mount device apparatus is provided in accordance with embodiment 1, and in particular, as shown in figures 2-3,
The top symmetry sliding connection of brace table 6 has limiting plate 51, be used for spacing the both sides of lead frame through limiting plate 51, be favorable to improving the precision of pay-off, slide hole 25 has been seted up to the inside of brace table 6 and the position that is located limiting plate 51 both ends, the inherent second connecting plate 52 in both ends of limiting plate 51, second connecting plate 52 sliding connection is in slide hole 25's inside, the bottom of two second connecting plates 52 is fixed with second regulation pole 22 jointly, the bottom symmetry of brace table 6 is fixed with dead lever 20, the second regulation pole 22 is located the position between two dead levers 20, symmetrically be fixed with guide arm 21 between two dead levers 20, the both ends and the guide arm 21 sliding connection of second regulation pole 22 are used for leading to limiting plate 51 and spacing through guide arm 21, the bottom of brace table 6 is fixed with double-end motor 24, the two output ends of double-end motor 24 are fixed with first threaded rod 23, the screw thread of two threaded rods 23 is opposite, two first threaded rods 23 respectively with second regulation pole 22 threaded connection, specific, drive first 23 through double-end motor 24 rotation, the second threaded rod 22 drives second threaded rod 22 when rotating, the second threaded rod 22 is close to each other or keep away from each other between two lead frame, can further adapt to the spacing between the lead frame, the device is further can be adjusted to the width between the lead frame, and can be adjusted, the width is further can be adjusted.
The using process of the lead frame surface mount device equipment provided by the invention is as follows:
technical principle: the fourth straight gear 44 is driven to rotate by the third single-head motor 42, the third straight gear 43 is driven to rotate by the engagement of the fourth straight gear 44 and the third straight gear 43, the sucking disc 49 is driven to rotate to right above the base plate, the sucking disc 49 is driven to move up and down by the electric telescopic seat 46, the chip on the base plate is further grabbed and attached to the base island 3, the first straight gear 27 is driven to rotate by the rotation of the second single-head motor 26, the first straight gear 27 drives the second straight gear 28 to rotate when rotating, the transmission rod 29 is driven to rotate by the second straight gear 28, the second single-head belt pulley 12 drives the first single-head belt pulley 10 to rotate by the first toothed transmission belt 11, the rocker 16 is driven to rotate by the first single-head belt pulley 10, the rocker 16 drives the first adjusting rod 18 to rotate when rotating, the first adjusting rod 18 pushes the push rod 15 to move through the connecting ring 39 and the rotating ring 40 when rotating, the push rod 15 drives the push block 38 to reciprocate through the first connecting plate 35 and the mounting shell 37, the push block 38 is separated from the inside of the positioning port 2 when moving backwards, the push block 38 is inserted into the positioning port 2 when pushing the positioning port 2 forwards, the frame edge 1 is driven to move forwards through pushing the positioning port 2, continuous feeding is realized, the push block 38 is limited through the stop block 9, the push block 38 is driven to reset through the reset spring 41, the double-head belt pulley 34 is driven to rotate through the rotation of the first single-head motor 17, the double-head belt pulley 34 drives the third single-head belt pulley 32 and the nut 31 through the second toothed transmission belt 33, the nut 31 is connected with the second threaded rod 30 through threads when rotating, thereby drive first regulation pole 18 and follow the axis direction of second threaded rod 30 and remove, through adjusting the distance between first regulation pole 18 to first single banded wheel 10 to adjust the motion stroke of ejector pad 38, rotate through double-end motor 24 and drive first threaded rod 23 and rotate, first threaded rod 23 drives second regulation pole 22 and be close to each other or keep away from the motion when rotating, thereby adjust the interval between two limiting plates 51, make the equipment can adapt to the lead frame of different width.
According to the lead frame surface mounting device, the intermittent driving part drives the pushing block to reciprocate and insert into the positioning opening, and the frame edge is driven to move forwards by pushing the positioning opening, so that continuous feeding is realized, the difficulty of manual operation is reduced, and the efficiency of an automatic production flow is improved.
In order to make the person skilled in the art better understand the solution of the present invention, the technical solution of the embodiment of the present invention will be clearly and completely described below with reference to the accompanying drawings.
It should be noted that, under the condition of no conflict, the embodiments of the present invention and the features and technical solutions in the embodiments may be combined with each other.
It should be noted that like reference numerals and letters refer to like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures.
In the present invention, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed, mechanically connected, electrically connected, or communicable with each other, directly connected, indirectly connected through an intervening medium, or in communication between two elements or in an interactive relationship between two elements, unless otherwise explicitly specified. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.
It is apparent that the above-described embodiments are only some embodiments of the present invention, but not all embodiments, and the preferred embodiments of the present invention are shown in the drawings, which do not limit the scope of the patent claims. This invention may be embodied in many different forms, but rather, embodiments are provided in order to provide a thorough and complete understanding of the present disclosure. Although the invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that modifications may be made to the embodiments described in the foregoing description, or equivalents may be substituted for elements thereof. All equivalent structures made by the content of the specification and the drawings of the invention are directly or indirectly applied to other related technical fields, and are also within the scope of the invention.