Device for processing edge of light guide plate
By introducing hydraulic rods and ash cleaning components into the light guide plate processing device, the damage problem of flue gas and dust on the light guide plate during the cutting process is solved, and higher quality light guide plate production and more uniform light propagation are achieved.
Patent Information
- Application Number
- CN202411746601.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-02
- Publication Date
- 2024-12-31
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
The existing devices used to process the edges of the light guide plate will produce high-temperature flue gas and dust splash during the cutting process, resulting in damage to the light guide spots on the surface of the light guide plate, affecting production quality, and failing to effectively remove dust on the surface of the light guide plate, resulting in The light is unevenly distributed.
A device including a processing box body, cutting assembly, exhaust assembly and dust removal assembly is designed. The block is driven down by a hydraulic rod to fit the light guide plate, the laser cutting head and sliding plate are cut, and the exhaust assembly is used to cool. The hot air is discharged and the ash cleaning assembly removes dust by spraying airflow.
It effectively avoids the damage to the light guide plate by high-temperature flue gas and dust during cutting, improves production quality, reduces heat accumulation, extends the service life of the cutting equipment, and improves the brightness and light uniformity of the light guide plate.
Smart Images
Figure CN119216825A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of light guide plate processing, and in particular relates to a device for processing the edge of a light guide plate. Background Art
[0002] A light guide plate is a flat optical element designed using optical principles, usually made of transparent materials such as polycarbonate and polymethyl methacrylate, which have excellent optical and processing properties and can meet the manufacturing requirements of light guide plates. The light guide plate uses optical-grade acrylic sheet as the base material, and forms light guide points on its bottom surface through high-tech materials and processes. These light guide points can guide light from the side or bottom to the front of the light guide plate to achieve uniform distribution of light.
[0003] However, the existing devices for processing the edges of light guide plates often have some problems in actual use: first, in the prior art, when processing the edges of light guide plates, they are mostly cut directly, and high-temperature smoke and dust will be generated during cutting. The high-temperature smoke and flying surface dust during cutting may damage the light guide points on the surface of the light guide plate, resulting in uneven brightness of the light guide plate, and color deviation affects the production quality of the light guide plate; secondly, most of the existing light guide plate cutting machines do not clean the plate before cutting. During the transportation process of the light guide plate placed inside the light guide plate cutting machine, its surface will come into contact with the air, thereby increasing the possibility of dust adhesion, which may cause an impact on the laser cutting process, thereby reducing the processing quality of the light guide plate. Summary of the invention
[0004] The object of the present invention is to provide a device for processing the edge of a light guide plate to solve the problems raised in the above background technology.
[0005] In order to achieve the above-mentioned purpose, the present invention provides the following technical solutions: A device for processing the edge of a light guide plate, comprising a processing box body, side panels are fixedly connected on both sides of the processing box body, a bottom plate is fixedly connected to the bottom of the inner side of the processing box body, the bottom plate is fixedly connected to the two side panels, a hydraulic rod is fixedly connected to the middle section of the top of the processing box body, a connecting rod is fixedly connected to the output end of the hydraulic rod, the connecting rod is slidably connected to the processing box body, a blocking block is provided inside the processing box body, a pressing plate is provided inside the blocking block, the pressing plate is fixedly connected to the connecting rod, a pressing chamber is opened inside the pressing plate, the pressing plate is slidably connected to the inside of the pressing chamber, cutting components are provided on both sides of the processing box body, an exhaust component is provided inside the processing box body, and a dust cleaning component is provided inside the processing box body.
[0006] Preferably, the cutting assembly includes two slide rails, both of which are fixedly connected to the processing box body, both of which are slidably connected to sliding plates inside, both of which are fixedly connected to connecting plates on one side, both of which are fixedly connected to fixed plates on one side, and both of which are fixedly connected to laser cutting heads on the bottom.
[0007] Preferably, the exhaust assembly includes two heat exchangers, and the two heat exchangers are fixedly connected to the middle section of the top of the sliding plate. One side of the two heat exchangers is fixedly connected with an intake pipe, and one side of the fixed plate is fixedly connected with a rubber clamp, and the intake pipe passes through the rubber clamp and is fixedly sleeved with the rubber clamp, and the bottom of the intake pipe is fixedly connected with an intake head, and one side of the intake head is fixedly connected with a connecting column, and the connecting column is rotatably connected to the laser cutting head, and one side of the heat exchanger is fixedly connected with an outlet pipe, and the outlet pipe passes through the processing box body and extends to the outside of the processing box body.
[0008] Preferably, the cleaning component includes an extruded rubber air silo, a connecting nozzle is fixedly connected to the bottom of the extruded rubber air silo, the connecting nozzle is threadedly connected to the bottom of the middle section of the pressing chamber, a plurality of mounting grooves are respectively opened around the bottom of the blocking block, a plurality of first springs are respectively fixedly connected inside the plurality of mounting grooves, a plurality of first support blocks are respectively fixedly connected to the bottom of the plurality of first springs, and the plurality of first support blocks are all slidably connected to the inside of the mounting grooves.
[0009] Preferably, the dust cleaning component also includes a plurality of L-shaped limit plates, and the plurality of L-shaped limit plates are fixedly connected to one side of the top of the base plate, a plurality of second support blocks are fixedly connected to the top of the base plate, a plurality of second support blocks are respectively fixedly connected to the tops of a plurality of second springs, a plurality of support plates are respectively fixedly connected to the tops of the plurality of second springs, a plurality of support plates are respectively fixedly connected to one side of the top of the base plate, and the plurality of support plates are respectively arranged corresponding to the plurality of L-shaped limit plates, and the second support blocks and support plates are arranged in fits with the L-shaped limit plates and the first limit plates.
[0010] Preferably, the position of the first support block corresponds to the support plate, the first support block is located in the middle of the support plate, and the first limiting plate and the inner side of the L-shaped limiting plate correspond to the outer side of the shielding block.
[0011] Preferably, the position of the connecting column corresponds to the laser cutting head, the connecting column can be rotated according to the angle of the laser cutting head, and the air outlet pipe has a length inside the processing box body that is not affected by the displacement of the sliding plate.
[0012] Preferably, the length and width of the pressing plate correspond to the pressing chamber, and the extruded rubber air chamber corresponds to the middle of the pressing plate.
[0013] The beneficial effects of the present invention are as follows: 1. The present invention applies pressure to the shielding block through the pressing plate, so that the pressure can press the shielding block, and the shielding block will drop to fit with the surface of the light guide plate. At this time, since the shielding block fits with the surface of the light guide plate, it can effectively avoid the damage to the surface of the light guide plate caused by high-temperature smoke and flying dust generated during cutting, thereby improving the production quality of the light guide plate. At this time, the laser cutting head and the sliding plate are started, and the sliding plate is started to drive the laser cutting head to cut the light guide plate. The hot air and smoke generated during cutting will be sucked into the suction head, and the hot air enters the heat exchanger through the suction pipe to cool and then is discharged through the outlet pipe. The hot air is quickly sucked out and cooled and discharged, which can effectively reduce the heat affected range of the cutting area, avoid deformation, burning or oxidation of the material due to overheating, thereby improving the quality of the cutting surface, avoiding heat accumulation in the cutting area, reducing thermal damage to the cutting head and the material, and thus extending the service life of the cutting equipment.
[0014] 2. The present invention starts the hydraulic rod, which drives the blocking block to descend. After the blocking block descends, it drives the first support block to descend and contact the surface of the light guide plate. At this time, the first support block supports the blocking block. At this time, the connecting rod continues to descend, which drives the pressing plate to continue to descend. The pressing plate descends and presses the extruded rubber air chamber. The extruded rubber air chamber is compressed, and the air inside it is compressed by the extruded rubber air chamber and sprayed onto the surface of the light guide plate through the connecting nozzle. The sprayed air is a column and will diffuse outward in a wave-like manner after contacting its surface. The diffused airflow will clear the dust on its surface, thereby removing these impurities, allowing light to pass through the light guide plate more smoothly, improving the overall brightness and uniformity, and preventing tiny particles in dust and dirt from scratching or wearing the surface of the light guide plate.
[0015] 3. The present invention arranges the second support block, the second spring and the support plate. When the hydraulic rod is started, the shielding block is driven to descend and contact the light guide plate. When the hydraulic rod descends too much, the support plate is pressed and the second spring is compressed at the same time, thereby effectively avoiding the damage of the light guide plate caused by excessive pressure applied by the hydraulic rod, thereby causing unnecessary losses. It can also effectively avoid scratches on the light guide plate due to pressure, thereby destroying the uniform propagation of light and affecting the processing effect of the light guide plate. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 2 It is a schematic diagram of the overall side structure of the present invention; Figure 3 It is a cross-sectional view of the processing box body of the present invention; Figure 4 For the present invention Figure 3 A magnified view of the structure at center; Figure 5is a cross-sectional view of the shielding block of the present invention; Figure 6 It is a structural schematic diagram of the slide rail of the present invention; Figure 7 This is a schematic diagram of the structure of the cutting assembly of the present invention; Figure 8 It is a schematic diagram of the structure of the L-shaped limiting plate of the present invention.
[0017] In the figure: 1. Processing box body; 2. Side plate; 3. Bottom plate; 4. Hydraulic rod; 5. Connecting rod; 6. Block; 7. Pressing plate; 8. Pressing chamber; 9. Slide rail; 10. Sliding plate; 11. Connecting plate; 12. Fixed plate; 13. Laser cutting head; 14. Heat exchanger; 15. Intake pipe; 16. Rubber clamp; 17. Intake head; 18. Connecting column; 19. Exhaust pipe; 20. Extruded rubber air chamber; 21. Connecting nozzle; 22. First spring; 23. First support block; 24. L-shaped limit plate; 25. Second support block; 26. Second spring; 27. Support plate; 28. First limit plate. DETAILED DESCRIPTION
[0018] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0019] like Figures 1 to 8 As shown, an embodiment of the present invention provides a device for processing the edge of a light guide plate, including a processing box body 1, side panels 2 are fixedly connected to the two sides of the processing box body 1, a bottom plate 3 is fixedly connected to the bottom of the inner side of the processing box body 1, and the bottom plate 3 is fixedly connected to the two side panels 2 respectively, a hydraulic rod 4 is fixedly connected to the middle section of the top of the processing box body 1, and a connecting rod 5 is fixedly connected to the output end of the hydraulic rod 4, and the connecting rod 5 is slidably connected to the processing box body 1, a shielding block 6 is arranged inside the processing box body 1, and a pressing plate 7 is arranged inside the shielding block 6, and the pressing plate 7 is fixedly connected to the connecting rod 5, and the pressing plate 7 is fixedly connected to the connecting rod 5. A pressing chamber 8 is provided inside the pressing plate 7, and the pressing plate 7 is slidably connected inside the pressing chamber 8. Cutting components are provided on both sides of the processing box body 1, an exhaust component is provided inside the processing box body 1, and a dust cleaning component is provided inside the processing box body 1. Pressure is applied to the shielding block 6 through the pressing plate 7, so that the pressure can press the shielding block 6, and the shielding block 6 will drop to fit with the surface of the light guide plate. At this time, since the shielding block 6 fits with the surface of the light guide plate, it can effectively avoid the damage to the surface of the light guide plate caused by high-temperature smoke and flying dust generated during cutting, thereby improving the production quality of the light guide plate.
[0020] Among them, the cutting assembly includes two slide rails 9, the two slide rails 9 are fixedly connected to the processing box body 1, the two slide rails 9 are slidably connected with sliding plates 10, one side of the two sliding plates 10 is fixedly connected with a connecting plate 11, one side of the two connecting plates 11 is fixedly connected with a fixed plate 12, and the bottom of the two fixed plates 12 is fixedly connected with a laser cutting head 13. The sliding plate 10 drives the laser cutting head 13 to move and cut the light guide plate, so that the length of the light guide plate meets the working standards, thereby improving work efficiency, reducing processing time, improving product quality, reducing damage to the product, and meeting diversified needs at the same time.
[0021] The exhaust assembly includes two heat exchangers 14, both heat exchangers 14 are fixedly connected to the middle section of the top of the sliding plate 10, one side of the two heat exchangers 14 is fixedly connected to an air intake pipe 15, one side of the fixed plate 12 is fixedly connected to a rubber clamp 16, the air intake pipe 15 passes through the rubber clamp 16 and is fixedly sleeved with the rubber clamp 16, the bottom of the air intake pipe 15 is fixedly connected to an air intake head 17, one side of the air intake head 17 is fixedly connected to a connecting column 18, the connecting column 18 is rotatably connected to the laser cutting head 13, one side of the heat exchanger 14 is fixedly connected to an air outlet pipe 19, the air outlet pipe 19 passes through the processing box body 1 and extends To the outside of the processing box body 1, the sliding plate 10 starts to drive the laser cutting head 13 to cut the light guide plate. The hot air and smoke generated during cutting will be sucked in by the suction head 17, and the hot air enters the heat exchanger 14 through the suction pipe 15 and is cooled and then discharged through the outlet pipe 19. The hot air is quickly sucked out and cooled and discharged, which can effectively reduce the heat affected range of the cutting area and avoid deformation, burning or oxidation of the material due to overheating, thereby improving the quality of the cutting surface, avoiding heat accumulation in the cutting area, reducing thermal damage to the cutting head and material, and thus extending the service life of the cutting equipment.
[0022] Among them, the dust cleaning component includes an extruded rubber air bin 20, a connecting nozzle 21 is fixedly connected to the bottom of the extruded rubber air bin 20, and the connecting nozzle 21 is threadedly connected to the bottom of the middle section of the pressing chamber 8. A plurality of mounting grooves are respectively opened around the bottom of the blocking block 6, and a plurality of first springs 22 are respectively fixedly connected inside the plurality of mounting grooves, and a plurality of first support blocks 23 are respectively fixedly connected to the bottom of the plurality of first springs 22, and a plurality of first support blocks 23 are all slidably connected inside the mounting grooves. The dust cleaning component also includes a plurality of L-shaped limit plates 24, and the plurality of L-shaped limit plates 24 are all fixedly connected to one side of the top of the bottom plate 3, a plurality of second support blocks 25 are fixedly connected to the top of the bottom plate 3, a plurality of second support blocks 25 are respectively fixedly connected to the top of the plurality of second springs 26, and a plurality of support plates 27 are respectively fixedly connected to the top of the plurality of second springs 26, and a plurality of support plates 27 are respectively fixedly connected to one side of the top of the bottom plate 3, and the plurality of support plates 27 are respectively arranged corresponding to the plurality of L-shaped limit plates 24 , the second support block 25 and the support plate 27 are arranged in contact with the L-shaped limit plate 24 and the first limit plate 28, and the hydraulic rod 4 is started. The hydraulic rod 4 is started to drive the blocking block 6 to descend. After the blocking block 6 descends, it will drive the first support block 23 to descend and contact the surface of the light guide plate. At this time, the first support block 23 supports the blocking block 6. At this time, the connecting rod 5 continues to descend and drives the pressing plate 7 to continue to descend. The pressing plate 7 descends and presses the extruded rubber air chamber 20 at the same time. The extruded rubber air chamber 20 is compressed, and the air inside it is compressed by the extruded rubber air chamber 20 and sprayed onto the surface of the light guide plate through the connecting nozzle 21. The sprayed air is a column and will diffuse outward in a wave-like manner after contacting its surface. The diffused airflow will remove the dust on its surface, thereby removing these impurities, so that the light can pass through the light guide plate more smoothly, thereby improving the overall brightness and uniformity, and at the same time avoiding the possibility of scratches or wear on the surface of the light guide plate by tiny particles in dust and dirt.
[0023] Among them, the position of the first support block 23 corresponds to the support plate 27, the first support block 23 is located in the middle of the support plate 27, and the inner side of the first limiting plate 28 and the L-shaped limiting plate 24 corresponds to the outer side of the blocking block 6, in order to better adapt to the light guide plate, thereby better protecting the light guide plate that needs to be processed, thereby improving production quality.
[0024] Among them, the position of the connecting column 18 corresponds to the laser cutting head 13, the connecting column 18 can be rotated according to the angle of the laser cutting head 13, the outlet pipe 19 has a length inside the processing box body 1 that is not affected by the displacement of the sliding plate 10, the length and width of the pressing plate 7 correspond to the pressing chamber 8, and the extruded rubber air chamber 20 corresponds to the middle part of the pressing plate 7. The connecting column 18 can be rotated according to the angle of the laser cutting head 13, so that the connecting column 18 can better absorb the smoke during cutting, thereby improving the protection of the light guide plate, avoiding thermal damage caused by high-temperature smoke, and thus extending the service life of the cutting equipment.
[0025] Working principle: During operation, the light guide plate to be cut is placed on the surface of the support plate 27, and the hydraulic rod 4 is started at this time. The hydraulic rod 4 drives the connecting rod 5 to descend, and the connecting rod 5 descends and drives the blocking block 6 to descend. After the blocking block 6 descends, it drives the first support block 23 to descend and contact the surface of the light guide plate. At this time, the first support block 23 supports the blocking block 6, and the connecting rod 5 continues to descend, which drives the pressing plate 7 to continue to descend. The pressing plate 7 descends and presses the extruded rubber air chamber 20 at the same time. The extruded rubber air chamber 20 is compressed, and the air inside it is compressed by the extruded rubber air chamber 20 and sprayed onto the surface of the light guide plate through the connecting nozzle 21. The sprayed air is a columnar shape and will diffuse outward in a wave-like manner after contacting its surface. The diffused airflow will remove the dust on its surface, thereby removing these impurities, so that the light can pass through the light guide plate more smoothly, improve the overall brightness and uniformity, and at the same time avoid the possibility of tiny particles in dust and dirt causing scratches or wear on the surface of the light guide plate; After the pressing plate 7 compresses the extruded rubber air chamber 20 to a certain extent, pressure will be applied to the shielding block 6 through the pressing plate 7, so that its pressure can press the shielding block 6, and the shielding block 6 will drop to fit with the surface of the light guide plate. At this time, since the shielding block 6 fits with the surface of the light guide plate, it can effectively avoid the damage to the surface of the light guide plate caused by the high-temperature smoke and flying dust generated during cutting, thereby improving the production quality of the light guide plate. At this time, the laser cutting head 13 and the sliding plate 10 are started, and the sliding plate 10 starts to drive the laser cutting head 13 to cut the light guide plate. The hot air and smoke generated during cutting will be sucked in by the suction head 17, and the hot air enters the heat exchanger 14 through the suction pipe 15 to cool and then is discharged through the outlet pipe 19. The hot air is quickly sucked out and cooled and discharged, which can effectively reduce the heat affected range of the cutting area, avoid deformation, burning or oxidation of the material due to overheating, thereby improving the quality of the cutting surface, avoiding heat accumulation in the cutting area, reducing thermal damage to the cutting head and the material, and thus extending the service life of the cutting equipment.
[0026] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.
[0027] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.
Claims
1. A device for processing the edge of a light guide plate, comprising a processing box body (1), wherein the two sides of the processing box body (1) are respectively fixedly connected to side panels (2), and the bottom of the inner side of the processing box body (1) is fixedly connected to a bottom panel (3), and the bottom panel (3) is respectively fixedly connected to the two side panels (2), characterized in that: A hydraulic rod (4) is fixedly connected to the middle section of the top of the processing box body (1), and a connecting rod (5) is fixedly connected to the output end of the hydraulic rod (4), and the connecting rod (5) is slidably connected to the processing box body (1). A shielding block (6) is arranged inside the processing box body (1), and a pressing plate (7) is arranged inside the shielding block (6). The pressing plate (7) is fixedly connected to the connecting rod (5), and a pressing chamber (8) is provided inside the pressing plate (7), and the pressing plate (7) is slidably connected to the inside of the pressing chamber (8). Cutting components are arranged on both sides of the processing box body (1), an exhaust component is arranged inside the processing box body (1), and a dust cleaning component is arranged inside the processing box body (1).
2. The device for processing the edge of a light guide plate according to claim 1, characterized in that: The cutting assembly comprises two slide rails (9), the two slide rails (9) are fixedly connected to the processing box body (1), the two slide rails (9) are slidably connected to the inside of the two slide rails (9), one side of the two slide plates (10) is fixedly connected to a connecting plate (11), one side of the two connecting plates (11) is fixedly connected to a fixed plate (12), and the bottom of the two fixed plates (12) is fixedly connected to a laser cutting head (13).
3. The device for processing the edge of a light guide plate according to claim 2, characterized in that: The exhaust assembly comprises two heat exchangers (14), the two heat exchangers (14) are fixedly connected to the middle section of the top of the sliding plate (10), one side of the two heat exchangers (14) is fixedly connected to an air intake pipe (15), one side of the fixed plate (12) is fixedly connected to a rubber clamping ring (16), the air intake pipe (15) passes through the rubber clamping ring (16) and is fixedly sleeved with the rubber clamping ring (16), the bottom of the air intake pipe (15) is fixedly connected to an air intake head (17), one side of the air intake head (17) is fixedly connected to a connecting column (18), the connecting column (18) is rotatably connected to the laser cutting head (13), and one side of the heat exchanger (14) is fixedly connected to an air outlet pipe (19), the air outlet pipe (19) passes through the processing box body (1) and extends to the outside of the processing box body (1).
4. The device for processing the edge of a light guide plate according to claim 3, characterized in that: The dust cleaning component comprises an extruded rubber gas chamber (20), a connecting nozzle (21) is fixedly connected to the bottom of the extruded rubber gas chamber (20), the connecting nozzle (21) is threadedly connected to the bottom of the middle section of the pressing chamber (8), a plurality of mounting grooves are respectively opened around the bottom of the shielding block (6), a plurality of first springs (22) are respectively fixedly connected inside the plurality of mounting grooves, a plurality of first support blocks (23) are respectively fixedly connected to the bottom of the plurality of first springs (22), and the plurality of first support blocks (23) are all slidably connected inside the mounting grooves.
5. The device for processing the edge of a light guide plate according to claim 4, characterized in that: The dust cleaning component further comprises a plurality of L-shaped limit plates (24), the plurality of L-shaped limit plates (24) are all fixedly connected to one side of the top of the bottom plate (3), a plurality of second support blocks (25) are fixedly connected to the top of the bottom plate (3), a plurality of second support blocks (25) are respectively fixedly connected to the top of a plurality of second springs (26), a plurality of support plates (27) are respectively fixedly connected to the top of a plurality of second springs (26), a plurality of support plates (27) are respectively fixedly connected to one side of the top of the bottom plate (3), the plurality of support plates (27) are respectively arranged corresponding to the plurality of L-shaped limit plates (24), and the second support blocks (25) and the support plates (27) are arranged in contact with the L-shaped limit plates (24) and the first limit plates (28).
6. The device for processing the edge of a light guide plate according to claim 5, characterized in that: The position of the first support block (23) corresponds to the support plate (27); the first support block (23) is located in the middle of the support plate (27); and the inner sides of the first limiting plate (28) and the L-shaped limiting plate (24) correspond to the outer sides of the shielding block (6).
7. The device for processing the edge of a light guide plate according to claim 6, characterized in that: The position of the connecting column (18) corresponds to the laser cutting head (13), the connecting column (18) can be rotated according to the angle of the laser cutting head (13), and the air outlet pipe (19) has a length inside the processing box body (1) that is not affected by the displacement of the sliding plate (10).
8. The device for processing the edge of a light guide plate according to claim 7, characterized in that: The length and width of the pressing plate (7) both correspond to the pressing chamber (8), and the extruded rubber air chamber (20) corresponds to the middle of the pressing plate (7).