Mould unit for annular polyurethane polishing disc production line

Abstract

The utility model relates to the field of pneumatic tool accessory production, in particular to a mould unit for an annular polyurethane polishing disk production line, the mould unit is mounted on a turntable of an annular production line, the mould unit comprises a bottom plate, a bottom mould and a cover mould, the bottom plate is mounted on the top surface of the turntable, the bottom mould is fixed on the bottom plate, the cover mould is rotatably connected to the bottom mould, and the cover mould is fixed on the turntable. The bottom die and the cover die can be rotationally opened or rotationally closed under the action of external force, a cooling module is arranged in the bottom plate, and a heating module is arranged in the bottom die; the mold has the advantages that the mold station adopts an automatic cover opening and closing structure, and the cover opening and closing angle can reach 180 degrees, so that a release agent can be automatically smeared conveniently; meanwhile, the heating module and the cooling module are arranged in the mold unit, so that a drying oven is omitted, and the cooling time is shortened; in addition, an electromagnet suction cup is further utilized, and releasing of mold cover opening and fastening of mold cover closing are achieved.

Description

Technical Field

[0001] This utility model relates to the field of pneumatic tool parts manufacturing, and in particular to a mold unit for a production line of annular polyurethane polishing discs. Background Technology

[0002] A pneumatic polishing machine is a tool that uses compressed air as a power source and is widely used for polishing and grinding the surfaces of various materials such as metal, wood, and plastic. The pneumatic polishing disc is a component installed at the rotating end of the pneumatic polishing machine, such as... Figure 1 and Figure 2 As shown, the pneumatic polishing disc (also known as a polyurethane polishing disc) includes a base, a polyurethane layer, a hook and loop fastener layer, and a polishing or grinding layer. The back of the base is fitted with a connector for fixing to the rotating end of the pneumatic polishing machine. The front of the base forms a polyurethane layer through an injection molding and foaming process. A hook and loop fastener layer is adhered to the surface of the polyurethane layer to secure the polishing or grinding layer.

[0003] Currently, the production of these polyurethane polishing pads mainly relies on manual operation: the mold (including the bottom mold and the top mold) needs to be manually cleaned and coated with a release agent by workers, and then the base is placed in the groove of the bottom mold; the workers carry the bottom mold with the base to the ester injection equipment, where the equipment injects polyurethane material; then, Velcro is placed on the uncured material and the top mold is closed, and the entire mold is sent into the oven for heating and foaming; after foaming is completed and it cools naturally, the mold is opened and the preliminarily formed polishing pad is taken out. Finally, the excess polyurethane scraps need to be manually cut off and the polishing or grinding layer is pasted on (the pasting process can also be done by the user), completing the final assembly.

[0004] The above-mentioned processing is highly dependent on manual labor, which is not conducive to reducing product costs and expanding production scale. Therefore, there is an urgent need for a circular production line for polyurethane polishing discs to improve the automation level of polishing disc production. The core of this type of production line is the structural design of individual mold units arranged on the circular production line.

[0005] Therefore, this case is brought. Utility Model Content

[0006] The purpose of this invention is to provide a mold unit for a production line of annular polyurethane polishing discs to solve the above-mentioned defects.

[0007] To achieve the above objectives, the technical solution of this utility model is as follows:

[0008] A mold unit for a ring-shaped polyurethane polishing disc production line is provided. The mold unit is installed on the turntable of the ring production line. The mold unit includes a base plate, a bottom mold, and a cover mold. The base plate is installed on the top surface of the turntable, the bottom mold is fixed on the base plate, and the cover mold is rotatably connected to the bottom mold. The cover mold can be rotated open or rotated closed under the action of external force. The base plate is provided with a cooling module, and the bottom mold is provided with a heating module.

[0009] Furthermore, an opening and closing module is provided between the bottom mold and the cover mold to apply force to the cover mold, causing the cover mold to open or close.

[0010] Furthermore, the opening and closing cover module includes a rotating shaft, a rack, a gear, and a rack translation drive unit. The rotating shaft is fixed on the cover mold, and a bushing is provided on the bottom mold. The rotating shaft is inserted into the bushing and is clearance-fitted with the bushing. The gear is fixed at the end of the rotating shaft. The rack is slidably connected to the bottom plate and meshes with the gear. The rack translation drive unit is fixed on the bottom plate and is used to drive the rack to perform reciprocating translational motion. The rack drives the gear to rotate, and the rotating shaft realizes the rotation of the cover mold relative to the bottom mold.

[0011] Furthermore, the maximum rotation angle of the cover mold relative to the bottom mold is 180°.

[0012] Furthermore, the cover mold is provided with an iron block, and the bottom mold is provided with an electromagnet chuck for adsorbing the iron block.

[0013] Furthermore, the bottom plate is rotatably connected to the top surface of the turntable at one end facing the center of the turntable, and a lifting unit is provided between the other end of the bottom plate and the top surface of the turntable. The lifting unit is used to lift the bottom plate so that the bottom plate is tilted at a certain angle relative to the turntable.

[0014] Furthermore, the lifting unit includes a lower support, a lower rotating block, an adjusting stud, an upper rotating block, an upper support, an upper fastening nut, and a lower fastening nut. The lower support is fixed to the top surface of the turntable, and the lower rotating block is rotatably connected to the lower support. The upper support is fixed to the bottom surface of the base plate, and the upper rotating block is rotatably connected to the upper support. The upper rotating block is provided with a through hole. One end of the adjusting stud is fixed to the lower rotating block, and the other end passes through the through hole. The upper fastening nut and the lower fastening nut are threadedly connected to the adjusting stud and are located on the upper and lower sides of the upper rotating block, respectively.

[0015] Furthermore, the heating module is a resistance heating module.

[0016] Furthermore, the cooling module adopts a water circulation cooling module.

[0017] The advantages of this utility model are: the mold station adopts an automated opening and closing structure, and the opening and closing angle can reach 180°, which facilitates the automated application of the release agent; at the same time, the mold unit is equipped with a heating module and a cooling module, eliminating the need for an oven and shortening the cooling time; in addition, an electromagnet chuck is used to realize the release of the mold opening and the fastening of the closing. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the three-dimensional structure of the polishing disc in the background art;

[0019] Figure 2 for Figure 1 An explosion diagram;

[0020] Figure 3 This is a schematic diagram of the plan layout of the annular polyurethane polishing disc production line in the embodiment;

[0021] Figure 4 This is a three-dimensional structural diagram of the mold unit in the embodiment, which is in a closed state.

[0022] Figure 5 for Figure 4 A three-dimensional structural diagram from another perspective;

[0023] Figure 6 This is a three-dimensional structural diagram of the mold unit in the embodiment, showing it in a 180° open state;

[0024] Figure 7 for Figure 4 A three-dimensional structural diagram from another perspective;

[0025] Figure 8 for Figure 1 A three-dimensional structural diagram, which does not show equipment such as the ester injection machine and suction pipes;

[0026] Figure 9 This is a schematic diagram of the turntable bottom surface structure in the embodiment;

[0027] Figure 10 This is a schematic diagram showing the state in which the flexible cotton brush of the oiling device in the embodiment is prepared to be lowered to remove the mold release agent;

[0028] Figure 11 This is a schematic diagram illustrating the application of release agent to the top and bottom molds using the oiling equipment in this embodiment.

[0029] Label Explanation

[0030] 101. Base; 102. Polyurethane layer; 103. Velcro layer;

[0031] 2. Frame; 201. Guide wheels;

[0032] 3. Turntable; 301. Guide rail groove;

[0033] 4. Mold Unit; 401. Base Plate; 402. Bottom Mold; 403. Cover Mold; 404. Rotating Shaft; 405. Rack; 406. Gear; 407. Rack Translation Drive Unit; 408. Iron Block; 409. Electromagnetic Chuck; 410. Lower Support; 411. Lower Rotating Block; 412. Adjusting Stud; 413. Upper Fastening Nut; 414. Lower Fastening Nut; 415. Upper Rotating Block; 416. Upper Support;

[0034] 5. Painting equipment; 501. Support frame; 502. Painting track; 503. Slider; 504. Painting lifting unit; 505. Painting rotating unit; 506. Release agent box; 507. Flexible cotton brush;

[0035] 6. Ester injection equipment. Detailed Implementation

[0036] The present invention will be further described in detail below with reference to the embodiments. It should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer" etc. indicated by the accompanying drawings are only for the convenience of describing the present invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention.

[0037] This embodiment proposes a production line for annular polyurethane polishing discs, such as... Figure 3 As shown, the machine includes a frame 2, a turntable drive unit is installed at the center of the frame 2, and a turntable 3 is slidably connected to the frame 2. The turntable drive unit is used to drive the turntable 3 to rotate. Eighteen mold units 4 are arranged in a ring on the top surface of the turntable 3. The turntable 3 is divided into a material unloading and cleaning station, an oiling station, a base placement station, an ester injection station, a Velcro placement station, a heating station, and a cooling station along its ring direction. An ester injection device 2 is provided in the ester injection station, and an oiling device 5 is provided in the oiling station.

[0038] like Figures 4 to 7 As shown, the mold unit 4 includes a base plate 401, a bottom mold 402, and a cover mold 403. The base plate 401 is installed on the top surface of the turntable 3. The bottom mold 402 is fixed to the base plate 401 by bolts. The cover mold 403 is rotatably connected to the bottom mold 402. The cover mold 403 can be rotated open or rotated closed under the action of external force. The base plate 401 is provided with a water circulation cooling module, and the bottom mold 402 is provided with a heating module.

[0039] Preferably, an opening and closing module is provided between the bottom mold 402 and the cover mold 403 to apply force to the cover mold 403, causing the cover mold 403 to open or close automatically. (Reference) Figure 5 The opening and closing module includes a rotating shaft 404, a rack 405, a gear 406, and a rack translation drive unit 407. The rotating shaft 404 is fixed on the cover mold 403, and a bushing is provided on the bottom mold 402. The rotating shaft 404 is inserted into the bushing and has a clearance fit with the bushing. The gear 406 is fixed to the end of the rotating shaft 404. The rack 405 is slidably connected to the base plate 401 and meshes with the gear 406. The rack translation drive unit 407 is fixed on the base plate 401 and is used to drive the rack 405 to perform reciprocating translational motion. The rack 405 drives the gear 406 to rotate, and the rotating shaft 404 realizes the rotation of the cover mold 403 relative to the bottom mold 402. Further, in this embodiment, the maximum rotation angle of the cover mold 403 relative to the bottom mold 402 is 180°.

[0040] After the bottom mold 402 and the top mold 403 are closed, the polyurethane foam will generate an expansion force that pushes the mold open. To increase the closing force of the bottom mold 402 and the top mold 403, refer to... Figure 4 In this embodiment, the cover mold 403 is provided with an iron block 408, and the bottom mold 402 is provided with an electromagnet chuck 409 for adsorbing the iron block 408. The adsorption force of the electromagnet chuck 409 is used to ensure the stability of the mold closing.

[0041] When mold unit 4 is placed horizontally and polyurethane liquid is injected, air is easily trapped in the gap between the liquid and the mold wall, forming bubbles. If these bubbles remain in the finished product, they will affect the quality and performance of the polishing disc. Experiments have shown that tilting the mold during ester injection helps the liquid polyurethane flow better and spread throughout the mold, and allows the liquid to contact the mold surface at a certain angle. This not only reduces the chance of air being trapped, but also makes it easier for the already formed microbubbles to rise and escape. Based on this, in this embodiment, one end of the base plate 401 facing the center of the turntable 3 is rotatably connected to the top surface of the turntable 3, and the other end of the base plate 401 is provided with a lifting unit between it and the top surface of the turntable 3. The lifting unit is used to lift the base plate 401, so that the base plate 401 is tilted at 10°-15° relative to the turntable 3. In this embodiment, the tilt angle is 13°.

[0042] refer to Figure 7The lifting unit includes a lower support 410, a lower rotating block 411, an adjusting stud 412, an upper rotating block 415, an upper support 416, an upper fastening nut 413, and a lower fastening nut 414. The lower support 410 is fixed to the top surface of the turntable 3, and the lower rotating block 411 is rotatably connected to the lower support 410. The upper support 416 is fixed to the bottom surface of the base plate 401, and the upper rotating block 415 is rotatably connected to the upper support 416. The upper rotating block 415 is provided with a through hole. One end of the adjusting stud 412 is fixed to the lower rotating block 411, and the other end passes through the through hole. The upper fastening nut 413 and the lower fastening nut 414 are threadedly connected to the adjusting stud 412 and are located on the upper and lower sides of the upper rotating block 415, respectively. The angle can be adjusted by loosening the upper fastening nut 413 and the lower fastening nut 414. After adjustment, tighten the upper fastening nut 413 and the lower fastening nut 414.

[0043] In this embodiment, the ester injection device 2 is an existing device used to inject polyurethane into the groove of the bottom mold 402.

[0044] In this embodiment, the oiling device 5 is a self-designed device used to apply oil to the opened bottom mold 402 and cover mold 403. For example... Figure 8 , Figure 10 , Figure 11 As shown, the oiling device 5 includes a support 501, an oiling track 502, a slider 503, an oiling lifting unit 504, an oiling rotating unit 505, a release agent tank 506, a slider drive unit (not shown in the figure), and a flexible cotton brush 507. The release agent tank 506 is used to store release agent. The support 501 stands on the outside of the turntable 3, and the oiling track 502, the release agent tank 506, and the slider 503 drive unit are fixed on it. The oiling track 502 is arranged parallel to the turntable 3 above it and points to the vertical axis where the center of the turntable 3 is located. The slider 503 is slidably connected to the oiling track 502 and driven by the slider drive unit. The oiling lifting unit 504 is installed on the slider 503, and the lifting end is fixed to the oiling rotating unit 505. The rotating end of the oiling rotating unit 505 is fixed to the flexible cotton brush 507. The release agent tank 506 is located directly below the oiling track 502.

[0045] The oiling device 5 is designed for the mold unit 4, which can be rotated 180°. For example... Figure 10As shown, when a mold unit 4 and the brushing track 502 are located on the same radial direction, the cover mold 403 of the mold unit 4 rotates 180° to open, and at the same time, the brushing lifting unit 504 descends, causing the flexible cotton brush 507 to be immersed in the release agent in the release agent tank 506. After being moistened, the flexible cotton brush 507 is lifted, and then the slider 503 is pushed, causing the flexible cotton brush 507 to move towards the cover mold 403 side; according to the inclination angle of the cover mold 403 and the bottom mold 402 relative to the horizontal plane, the brushing... During the translation process, the lifting unit 504 adjusts its height in real time to ensure that the flexible cotton brush 507 remains in contact with the cover mold 403 and the bottom mold 402 without affecting the translation of the slider 503. Simultaneously, the flexible cotton brush 507 deforms upon contact, further preventing any impact on the slider 503's translation. Additionally, when the flexible cotton brush 507 contacts the cover mold 403 and the bottom mold 402, the brushing rotation unit 505 rotates the flexible cotton brush 507 to improve the application effect of the release agent. After brushing the cover mold 403 and the bottom mold 402, the flexible cotton brush 507 rises and returns to its initial position for brushing the next mold unit 4.

[0046] like Figure 8 and Figure 9 As shown, the sliding connection between the frame 2 and the turntable 3 is as follows: the frame 2 is equipped with a guide wheel 201 to support the turntable 3, and the bottom surface of the turntable 3 is provided with a guide rail groove 301 that can cooperate with the guide wheel 201 to achieve smooth rotation of the turntable 3.

[0047] In this embodiment, both the rack translation drive unit 407 and the brushing lifting unit 504 adopt servo electric cylinders, the brushing rotation unit 505 adopts a servo motor, and the slider drive unit can adopt a lead screw mechanism, servo electric cylinder, etc.

[0048] Continue to refer to Figure 1 The operating process of this production line is as follows (the workshop temperature is maintained at 25℃):

[0049] At the material unloading and cleaning station, a worker is assigned to remove the polishing disc from the mold unit 4 after it has been opened, and to clean the mold unit 4 after it has been opened (by scraping off some of the polyurethane stuck to the mold unit 4 with a scraper).

[0050] At the painting station, the painting equipment 5 applies release agent to the cover mold 403 and bottom mold 402, which are opened at 180°.

[0051] A workstation is set up at the base 101, where a worker places the base 101 into the groove of the bottom mold 402;

[0052] At the ester injection station, the ester injection machine injects polyurethane into the groove of the bottom mold 402;

[0053] At the Velcro placement station, a worker is assigned to place the Velcro onto the polyurethane liquid. Then, the opening and closing cover mold 403 is activated, rotating the cover mold 403 180° to close with the bottom mold 402. At the same time, the electromagnet chuck 409 is activated to attract the iron block 408 on the cover mold 403.

[0054] When the closed mold unit 4 enters the heating station, the heating module inside the bottom mold 402 is activated to heat the polyurethane inside the mold unit 4. The polyurethane foaming temperature is generally between 35℃ and 40℃. In this embodiment, the heating module is based on resistance heating, which can quickly raise the temperature of the bottom mold 402 to about 42℃. Then, the heat is transferred to the polyurethane in the groove through heat transfer. During the movement of the turntable 3, the polyurethane foams quickly (with a precise ratio of polyether polyol and isocyanate of 1:1 or 1:1.05, and with the addition of catalysts, foaming agents and other additives, foaming can be completed in about 40 seconds and preliminary curing can begin. After preliminary curing, it can be removed).

[0055] When mold unit 4 enters the cooling station, the water circulation cooling module in the base plate 401 is activated, and the heating module in the bottom mold 402 is turned off. The water circulation cooling module in the base plate 401 cools down the bottom mold 402 and the cover mold 403. It needs to be cooled down to about 30℃-35℃ to facilitate workers to remove it. After that, mold unit 4 will cool down naturally during the rotation of turntable 3. When it reaches the ester injection station, the temperature of the bottom mold 402 is generally between 25℃-30℃.

[0056] When the material enters the unloading and cleaning station, the water circulation cooling module stops, and the workers begin cleaning and unloading. The polishing pads are then placed at the cutting equipment in the workshop to wait for the corresponding scraps to be cut off. During the waiting process, the polyurethane in the polishing pads is completely cured.

[0057] In addition, due to the volatile substances that may produce irritating odors during the foaming process, this embodiment also provides air suction pipes at the heating and cooling stations to absorb the volatile substances generated during polyurethane foaming, ensuring the health of workers in the workshop and the comfort of the working environment.

[0058] The above embodiments are only used to explain the concept of this utility model, and are not intended to limit the protection of this utility model. Any non-substantial modifications made to this utility model using this concept should fall within the protection scope of this utility model.

Claims

1. A mold unit for a ring-shaped polyurethane polishing disc production line, the mold unit being installed on a turntable of a ring-shaped production line, characterized in that, The mold unit comprises a bottom plate, a bottom mold and a cover mold, the bottom plate is installed on the top surface of the rotating disc, the bottom mold is fixed on the bottom plate, the cover mold is rotationally connected on the bottom mold, and the cover mold can be opened or closed by rotation under external force, the bottom plate is internally provided with a cooling module, and the bottom mold is internally provided with a heating module.

2. A mold unit for a continuous polyurethane polishing disc production line as claimed in claim 1, characterized in that, An opening and closing module is arranged between the bottom mold and the cover mold to apply force to the cover mold to open or close the cover mold.

3. A mold unit for a continuous polyurethane polishing disc production line as claimed in claim 2, characterized in that, The opening and closing module comprises a rotating shaft, a rack, a gear and a rack translation driving part, the rotating shaft is fixed on the cover mold, the bottom mold is provided with a shaft sleeve, the rotating shaft is inserted into the shaft sleeve and gap-fitted with the shaft sleeve, the end of the rotating shaft is fixed with the gear, the rack is slidingly connected on the bottom plate and engaged with the gear, the rack translation driving part is fixed on the bottom plate to drive the rack to make reciprocating translation movement, the rack drives the gear to rotate, and the rotating shaft realizes the rotation of the cover mold relative to the bottom mold.

4. A mold unit for a continuous polyurethane polishing disc production line as claimed in claim 3, characterized in that, The rotation angle of the cover mold relative to the bottom mold is maximum 180°.

5. A mold unit for a continuous polyurethane polishing disc production line as defined in claim 1, characterized in that, The cover mold is provided with an iron block, and the bottom mold is provided with an electromagnet chuck for adsorbing the iron block.

6. A mold unit for a continuous polyurethane polishing disc production line as defined in claim 1, characterized in that, One end of the bottom plate towards the center of the rotating disc is rotationally connected with the top surface of the rotating disc, the other end of the bottom plate is provided with a jacking unit relative to the top surface of the rotating disc, and the jacking unit is used to jack up the bottom plate to make the bottom plate inclined at a certain angle relative to the rotating disc.

7. A mold unit for a continuous polyurethane polishing disc production line as claimed in claim 6, characterized in that, The jacking unit comprises a lower support, a lower rotating block, an adjusting stud, an upper rotating block, an upper support, an upper fastening nut and a lower fastening nut, the lower support is fixed on the top surface of the rotating disc, the lower rotating block is rotationally connected on the lower support, the upper support is fixed on the bottom surface of the bottom plate, the upper rotating block is rotationally connected on the upper support, and the upper rotating block is provided with a through hole, one end of the adjusting stud is fixed with the lower rotating block, the other end passes through the through hole, and the upper fastening nut and the lower fastening nut are threadedly connected on the adjusting stud and respectively located on the upper and lower sides of the upper rotating block.

8. A mold unit for a continuous polyurethane polishing disc production line as defined in claim 1, characterized in that, The heating module adopts a resistance type heating module.

9. A mold unit for a continuous polyurethane polishing disc production line as defined in claim 1, characterized in that, The cooling module adopts a water circulation cooling module.

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