Low pressure glue injection apparatus
Patent Information
- Application Number
- CN202522401475.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-11
- Publication Date
- 2026-10-27
- Estimated Expiration
- 2035-11-11
AI Technical Summary
[0003]目前低压注塑工艺所采用的低压注胶设备通常包括熔胶缸和注胶枪等结构，其中熔胶缸用于将固态的热熔胶转化为可流动的熔融胶液，注胶枪用于将熔胶缸中备好的熔融胶液以低压方式精准注入目标模具型腔，然而现有的低压注胶设备还存在以下问题：(1)现有的熔胶缸大多为胶缸底座和胶筒组成的一体式结构，胶筒不可拆卸，在胶筒整体受热后，全部胶料熔化而成的胶水往往因为生产中每次的注胶量仅为几克至十几克，需要长时间才能全部用尽，而大量的胶料在胶筒内长时间加热后，容易出现碳化残留、结垢或结块等现象，一体式结构的熔胶缸在清理时需深入设备内部进行操作，不方便工作人员清理，而且切换不同的热熔性材料时必须彻底清空残留材料，不仅耗时，而且容易因残留导致材料混合，影响产品质量；(2)现有的注胶枪与液压传动系统中的泵体、调压阀为分体式连接结构，注胶枪与泵体之间一般通过连接管进行连接，胶料输送路径较长，此类结构在长时间使用或温度不正常的情况下，容易出现胶料堵塞在连接管内的现象，还需要在连接管处进行保温处理
[0017]1、本实用新型通过将熔胶缸组件设计为胶缸外筒与胶缸内筒的分体式结构，可以将胶缸内筒从胶缸外筒上拆卸下来，更容易对胶缸内筒进行替换或清洁操作，还能够根据需求更换相应容量规格的胶缸内筒，而且能够避免不同材料交叉污染。
Smart Images
Figure CN224897883U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of low-pressure dispensing, and in particular to a low-pressure dispensing device. Background Technology
[0002] Low-pressure injection molding is an injection molding process that injects specific hot melt materials into a mold with low injection pressure and low clamping force to encapsulate, fix or shape the product. Its core feature is the gentle molding effect brought by low pressure, which is especially suitable for precision or fragile parts such as high-pressure sensitive electronic components and wire harnesses.
[0003] Currently, the low-pressure injection molding process typically uses low-pressure injection equipment, which usually includes a melting cylinder and a glue gun. The melting cylinder is used to convert solid hot melt glue into a flowable molten glue, and the glue gun is used to accurately inject the molten glue prepared in the melting cylinder into the target mold cavity at low pressure. However, the existing low-pressure injection equipment still has the following problems: (1) Most of the existing melting cylinders are integrated structures consisting of a cylinder base and a glue tube. The glue tube cannot be disassembled. After the glue tube is heated as a whole, the glue formed by the melting of all the glue is often used up in a long time because the amount of glue injected each time is only a few grams to a dozen grams. A large amount of glue is heated in the glue tube for a long time. Carbonization residue, scaling or clumping are likely to occur. The integrated structure of the melting cylinder requires deep operation inside the equipment during cleaning, which is inconvenient for staff to clean. Moreover, when switching different hot melt materials, the residual material must be completely emptied, which is not only time-consuming, but also easy to cause material mixing due to residue, affecting product quality. (2) The existing glue gun and the pump body and pressure regulating valve in the hydraulic transmission system are separate connection structures. The glue gun and the pump body are generally connected through a connecting pipe. The glue conveying path is long. Under the condition of long-term use or abnormal temperature, the glue is prone to blockage in the connecting pipe. It is also necessary to perform heat preservation treatment at the connecting pipe. Utility Model Content
[0004] The technical problem solved by this utility model is to address the deficiencies in the prior art by providing a low-pressure dispensing device to solve the problems mentioned in the background art.
[0005] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows: A low-pressure glue injection device includes a melt cylinder assembly and a glue injection assembly integrating a gun pump valve; the melt cylinder assembly includes an outer cylinder, an inner cylinder, and a heater; the inner wall of the outer cylinder is provided with a plurality of sheet-like first heating grids evenly spaced along the circumference, and the bottom of the outer cylinder is provided with a first discharge port; the inner cylinder is nested inside the outer cylinder, and the side wall of the inner cylinder is provided with a plurality of second heating grids evenly spaced along the circumference, the second heating grids being inwardly protruding shells matching the shape of the first heating grids, and the bottom of the inner cylinder is provided with a second discharge port corresponding to the first discharge port; the heater is located on the outside of the outer cylinder; the glue injection assembly integrating a gun pump valve includes a series of... The system includes a pressure regulating valve, a gear pump, and a glue gun. The gear pump consists of a pump body and a gear mechanism. The pump body has a liquid storage chamber, and the side wall of the pump body has an inlet hole that communicates with the liquid storage chamber. The inlet hole is connected to an inlet connector. One end of the pump body has an outlet hole that communicates with the liquid storage chamber. The gear mechanism is located in the liquid storage chamber and is used to drive the flow of the adhesive. The glue gun has an injection chamber, one end of which communicates with the outlet hole, and the other end is used as an injection port. The pressure regulating valve includes a hot runner needle valve cylinder and a valve needle. The hot runner needle valve cylinder is mounted on the pump body. One end of the valve needle is connected to the hot runner needle valve cylinder, and the other end passes through the liquid storage chamber and the injection chamber, extending towards the injection port. The hot runner needle valve cylinder is used to drive the valve needle to make linear reciprocating motion along the axial direction.
[0006] As a further explanation of the above technical solution:
[0007] In the above technical solution, the pump body includes a gear pump sleeve and an upper cover, an intermediate body, and a lower cover installed sequentially inside the gear pump sleeve; the gear mechanism includes a drive shaft, a driven shaft, a drive gear, a driven gear, and a motor. One end of the drive shaft is rotatably connected to the lower cover, and the other end moves sequentially through the upper cover and the pressure regulating valve and is connected to the output end of the motor. The driven shaft is parallel to the drive shaft, and both ends of the driven shaft are rotatably connected to the upper cover and the lower cover, respectively. The drive gear and the driven gear are coaxially connected to the drive shaft and the driven shaft, respectively, and the drive gear meshes with the driven gear; a mounting base is fixedly connected to the bottom of the pressure regulating valve, and the mounting base is used to install on the equipment workbench. The motor is fixedly connected to the mounting base.
[0008] In the above technical solution, the hot runner needle valve cylinder includes a cylinder body, a first cylinder front cover, a first piston, and a first piston rod. The cylinder body has a cylindrical first cavity. The first cylinder front cover is fixedly connected to the opening end of the first cavity. The first cylinder front cover has a guide hole. The first piston is located in the first cavity and slides against the inner wall of the first cavity. One end of the first piston rod is fixedly connected to the first piston, and the other end movably passes through the guide hole of the first cylinder front cover and is threadedly connected to a valve needle seat. The valve needle seat has a T-shaped through groove. The connection end between the valve needle and the hot runner needle valve cylinder has a cylindrical limiting head. The diameter of the limiting head is larger than the diameter of the valve needle, and an annular first step is formed between the limiting head and the side wall of the valve needle. The valve needle is connected to the T-shaped through groove through the limiting head.
[0009] In the above technical solution, a valve needle sleeve opposite to the valve needle seat is also installed on the pump body; the end of the valve needle away from the valve needle seat moves sequentially through the valve needle sleeve, the liquid storage chamber and the liquid outlet and is inserted into the glue injection chamber.
[0010] In the above technical solution, the cylinder body is also provided with a cylindrical second cavity. The hot runner needle valve cylinder also includes a second cylinder front cover, a second piston, and a second piston rod. The second cylinder front cover is fixedly connected to the opening end of the second cavity. The second cylinder front cover is also provided with a guide hole. The second piston is located in the second cavity and slides against the inner wall of the second cavity. One end of the second piston rod is fixedly connected to the second piston, and the other end moves out of the guide hole of the second cylinder front cover and is threaded with a counterscrew. The pump body is also provided with a first safety channel, a second safety channel, a third safety channel, and a pressure regulating valve assembly. The first safety channel is cylindrical and coaxially arranged with the counterscrew. One end of the second safety channel is connected to the liquid outlet and the end of the liquid storage chamber near the liquid outlet. The first safety channel has one end connected to the first safety channel and the other end connected to the first safety channel. A cylindrical connecting channel is provided between the second safety channel and the first safety channel. The inner diameter of the connecting channel is smaller than the inner diameter of the first channel, and a tapered second step is formed between the connecting channel and the first channel. One end of the third safety channel is connected to the first safety channel, and the other end is connected to the side of the liquid storage chamber near the liquid inlet. The pressure regulating valve assembly includes a pressure regulating valve top rod and a steel ball. One end of the pressure regulating valve top rod is inserted into the first channel and slides against the inner wall of the first channel, while the other end is located outside the first channel and rests on the top screw. The steel ball is located in the first channel and between the second step and the pressure regulating valve top rod. The diameter of the steel ball is larger than the inner diameter of the connecting channel and smaller than the inner diameter of the first safety channel.
[0011] In the above technical solution, the cylinder block is also provided with a first intake channel, a second intake channel and a third intake channel. The intake ports of the first intake channel, the second intake channel and the third intake channel are respectively connected to a first quick connector, a second quick connector and a third quick connector. The first intake channel is connected to the rodless cavity of the first chamber, the second intake channel is connected to the rod cavity of the first chamber, and the third intake channel is connected to the rodless cavity of the second chamber.
[0012] In the above technical solution, the glue gun includes a glue gun sleeve and a gun body and a heating coil installed inside the glue gun sleeve. One end of the gun body is provided with a connector that plugs into the liquid outlet of the pump body, and the other end is connected to a nozzle. A spacer is coaxially installed inside the gun body, and the glue injection cavity is formed inside the spacer and the nozzle. The heating coil is arranged around the outside of the gun body.
[0013] In the above technical solution, a fixed base is fixedly connected to the bottom of the outer cylinder of the glue cylinder. The fixed base is provided with a connecting through hole that communicates with the first discharge port of the outer cylinder of the glue cylinder. The bottom end of the connecting through hole is connected to the liquid inlet connector of the pump body.
[0014] In the above technical solution, the heater includes a coil frame and an induction coil. The coil frame is sleeved on the outside of the outer cylinder of the rubber cylinder and fixedly connected to the outer cylinder. Multiple sets of wire grooves are arranged around the outside of the coil frame, and the induction coil is arranged around the outside of the coil frame and inserted into the wire grooves.
[0015] In the above technical solution, the upper outer wall of the outer cylinder of the glue cylinder is provided with multiple connecting ears at intervals along the circumference. The connecting ears are provided with connecting holes, and screws that are threadedly connected to the coil skeleton pass through the connecting holes.
[0016] Compared with the prior art, the beneficial effects of this utility model are as follows:
[0017] 1. This utility model designs the glue melting cylinder assembly as a separate structure of the outer cylinder and the inner cylinder, which allows the inner cylinder to be disassembled from the outer cylinder, making it easier to replace or clean the inner cylinder. It also allows for the replacement of the inner cylinder with a different capacity as needed, and avoids cross-contamination between different materials.
[0018] 2. The integrated gun-pump-valve dispensing assembly of this utility model integrates a pressure regulating valve, a gear pump, and a dispensing gun. The gear pump provides power to the dispensing gun, enabling it to smoothly inject the adhesive into the cavity of the injection mold. The adhesive enters the storage chamber from the inlet of the pump body and flows directly into the dispensing chamber of the dispensing gun through the storage chamber and the outlet. The outlet is directly connected to the dispensing gun, greatly shortening the flow path, ensuring smooth flow of the adhesive, reducing pressure loss, minimizing adhesive blockage, and making the dispensing pressure more stable. Attached Figure Description
[0019] Figure 1 This is a schematic diagram of the structure of this utility model;
[0020] Figure 2 This is a schematic diagram of the outer cylinder and inner cylinder of the glue cylinder in this utility model;
[0021] Figure 3 This is a cross-sectional view of the outer cylinder and the inner cylinder of the glue cylinder in this utility model;
[0022] Figure 4 This is an exploded structural diagram of the integrated glue injection assembly of the gun, pump, and valve in this utility model.
[0023] Figure 5 This is a cross-sectional view of the integrated glue injection assembly with pump and valve in this utility model.
[0024] Figure 6 This is a cross-sectional view from another perspective of the integrated glue injection assembly of the gun, pump, and valve in this utility model;
[0025] Figure 7 This is a schematic diagram of the integrated glue injection assembly of the gun, pump, and valve in this utility model.
[0026] Figure 8 This is a cross-sectional view of the gear pump in this utility model.
[0027] In the diagram: 1. Outer cylinder of the glue cylinder; 11. First heating grid; 12. First discharge port; 13. Connecting lug; 2. Inner cylinder of the glue cylinder; 21. Second heating grid; 22. Second discharge port; 3. Heater; 31. Coil frame; 311. Wire groove; 32. Induction coil; 4. Pressure regulating valve; 41. Hot runner needle valve cylinder; 411. Cylinder body; 411a. First cavity; 411b. Second cavity; 412. First air... Cylinder front cover; 413, First piston; 414, First piston rod; 415, Second cylinder front cover; 416, Second piston; 417, Second piston rod; 42, Valve needle; 421, Limit head; 5, Gear pump; 51, Pump body; 511, Gear pump sleeve; 512, Upper cover; 513, Intermediate body; 514, Lower cover; 52, Gear mechanism; 521, Drive shaft; 522, Driven shaft; 523, Drive gear. 524. Driven gear; 525. Motor; 6. Glue gun; 61. Glue gun sleeve; 62. Gun body; 621. Connector; 622. Nozzle; 623. Spacer; 63. Heating coil; 7. Liquid storage chamber; 8. Liquid inlet; 81. Liquid inlet connector; 9. Liquid outlet; 10. Glue injection chamber; 101. Injection port; 20. Mounting base; 30. Valve needle seat; 301. T-slot; 40. Valve needle sleeve; 50. Top-mounted Screw; 60, First safety passage; 70, Second safety passage; 80, Third safety passage; 90, Pressure regulating valve assembly; 901, Pressure regulating valve top rod; 902, Steel ball; 100, Connecting passage; 200, First air intake passage; 210, First quick connector; 300, Second air intake passage; 310, Second quick connector; 400, Third air intake passage; 410, Third quick connector; 500, Mounting base. Detailed Implementation
[0028] The present invention will now be described in further detail with reference to the accompanying drawings.
[0029] The embodiments described with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application. In the description of this application, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "several" or "more than" means two or more, unless otherwise explicitly specified. In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances. In this application, unless otherwise expressly specified and limited, "above" or "below" a second feature can include direct contact between the first and second features, or it can include contact between the first and second features through another feature between them. Moreover, "above," "over," and "on top" of a second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" of a second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.
[0030] like Figure 1-8 As shown, a low-pressure dispensing device includes a melt cylinder assembly and a dispensing assembly that integrates a gun pump valve.
[0031] The melting cylinder assembly includes an outer cylinder 1, an inner cylinder 2, and a heater 3. The inner wall of the outer cylinder 1 is evenly spaced with multiple sheet-like first heating grids 11, which are integrally formed with the outer cylinder 1. The bottom of the outer cylinder 1 has a first discharge port 12. The inner cylinder 2 is nested inside the outer cylinder 1, allowing it to be easily removed for cleaning. This facilitates thorough cleaning of residual aged adhesive and carbon deposits within the inner cylinder 2. Multiple spare inner cylinders 2 can also be prepared for preheating and melting different materials during production. Material switching can be achieved simply by replacing the inner cylinder 2 of the glue cylinder, eliminating the need to wait for the original inner cylinder 2 to cool down and be cleaned before reheating and feeding, thus improving production changeover efficiency. Furthermore, the inner cylinder 2 of the glue cylinder can be replaced with one of the appropriate capacity as needed, and cross-contamination between different materials can be avoided. Multiple second heating grids 21 are evenly spaced along the circumference of the side wall of the inner cylinder 2. Each second heating grid 21 is an inwardly protruding shell matching the shape of the first heating grid 11, and is integrally formed with the inner cylinder 2. The bottom of the inner cylinder 2 has a second discharge port 22 corresponding to the first discharge port 12. A heater 3 is located on the outside of the outer cylinder 1. Heating is achieved through the heater 3 on the outside of the outer cylinder 1, and the heat is conducted to the inner cylinder 2 through the first heating grid 11 of the outer cylinder 1 and the second heating grids 21 of the inner cylinder 2, causing the solid glue to reach a molten and flowing state. The evenly spaced first heating grids 11 and second heating grids 21 ensure uniform heating of the glue.
[0032] The integrated gun-pump-valve dispensing assembly includes a pressure regulating valve 4, a gear pump 5, and a dispensing gun 6 connected in sequence. The gear pump 5 includes a pump body 51 and a gear mechanism 52. The pump body 51 has a liquid storage chamber 7, and the side wall of the pump body 51 has a liquid inlet 8 communicating with the liquid storage chamber 7. The liquid inlet 8 is connected to a liquid inlet connector 81. One end of the pump body 51 has a liquid outlet 9 communicating with the liquid storage chamber 7. The gear mechanism 52 is located in the liquid storage chamber 7 and is used to drive the glue material in the liquid storage chamber 7 to flow to the dispensing gun 6 when it is working. The dispensing gun 6 has a dispensing chamber 10. One end of the dispensing chamber 10 is connected to the liquid outlet 9, and the other end is a molding inlet 101 for molten glue. Material is injected into the target mold cavity from the injection port 101; the pressure regulating valve 4 includes a hot runner needle valve cylinder 41 and a valve needle 42. The hot runner needle valve cylinder 41 is mounted on the pump body 51. One end of the valve needle 42 is connected to the hot runner needle valve cylinder 41, and the other end passes through the liquid storage chamber 7 and the glue injection chamber 10, and extends towards the injection port 101. The hot runner needle valve cylinder 41 is used to drive the valve needle 42 to make linear reciprocating motion along the axial direction, so that the valve needle 42 blocks the injection port 101 and stores the glue in the glue injection chamber 10, or separates the valve needle 42 from the injection port 101, so that the glue can be discharged from the injection port 101.
[0033] In this embodiment, reference Figure 1 , Figure 4 and Figure 6 The pump body 51 includes a gear pump sleeve 511 and an upper cover 512, an intermediate body 513, and a lower cover 514 sequentially installed inside the gear pump sleeve 511. The gear mechanism 52 includes a drive shaft 521, a driven shaft 522, a drive gear 523, a driven gear 524, and a motor 525. One end of the drive shaft 521 is rotatably connected to the lower cover 514, and the other end passes through the upper cover 512 and the pressure regulating valve 4 sequentially and is connected to the output end of the motor 525. The driven shaft 522 is parallel to the drive shaft 521, and both ends of the driven shaft 522 are rotatably connected to the upper cover 512 and the lower cover 514, respectively. The drive gear 523 and the driven gear 524 are coaxially connected to the drive shaft 521 and the driven shaft 522, respectively, and the drive gear 523 meshes with the driven gear 524. A mounting base 20 is fixedly connected to the bottom of the pressure regulating valve 4. The mounting base 20 is used to install on the equipment workbench, and the motor 525 is fixedly connected to the mounting base 20. It should be noted that a seal is provided between the drive shaft 521 and the upper cover 512 to prevent leakage of the adhesive in the storage chamber 7. The gear pump 5 provides power to the glue gun 6, enabling the glue gun 6 to smoothly inject the adhesive into the cavity of the injection mold. Specifically, the motor 525 drives the drive shaft 521 to rotate, the drive shaft 521 drives the drive gear 523 to rotate, the drive gear 523 drives the driven gear 524 and the driven shaft 522 to rotate, and the rotation of the drive gear 523 and the driven gear 524 causes the adhesive to flow. The flow path of the adhesive is as follows: it enters the storage chamber 7 from the inlet hole 8, and flows directly into the glue injection chamber 10 of the glue gun 6 through the storage chamber 7 and the outlet hole 9. Since the outlet hole 9 is directly connected to the glue gun 6, the flow path is greatly shortened, ensuring smooth flow of the adhesive and reducing the occurrence of adhesive blockage.
[0034] In this embodiment, reference Figure 4-5The hot runner needle valve cylinder 41 includes a cylinder body 411, a first cylinder front cover 412, a first piston 413, and a first piston rod 414. The cylinder body 411 has a cylindrical first cavity 411a. The first cylinder front cover 412 is fixedly connected to the opening end of the first cavity 411a. The first cylinder front cover 412 has a guide hole. The first piston 413 is located inside the first cavity 411a and slides against the inner wall of the first cavity 411a. One end of the first piston rod 414 is connected to the first piston rod 414. The piston 413 is fixedly connected, and the other end moves through the guide hole of the front cover 412 of the first cylinder and is threadedly connected to the valve needle seat 30. The valve needle seat 30 is provided with a T-shaped through groove 301. The valve needle 42 is provided with a cylindrical limiting head 421 at the connection end with the hot runner needle valve cylinder 41. The diameter of the limiting head 421 is larger than the diameter of the valve needle 42. An annular first step is formed between the limiting head 421 and the side wall of the valve needle 42. The valve needle 42 is connected to the T-shaped through groove 301 through the limiting head 421. It should be noted that the first piston 413 and the inner wall of the first cavity 411a are fitted with a precise clearance, which will not cause leakage due to excessive clearance, nor will it cause jamming due to insufficient clearance. A sealing groove can be provided around the outer wall of the piston, and a piston sealing ring is fitted inside the sealing groove to ensure that the first piston 413 and the inner wall of the first cavity 411a are tightly fitted. A guide sleeve can be pressed into the guide hole of the first cylinder front cover 412, and the first piston rod 414 is fitted with the inner hole of the guide sleeve with a clearance. At the same time, a corresponding sealing element is installed, and the sealing element is tightly fitted with the surface of the piston rod to prevent the medium from seeping out along the gap between the first piston rod 414 and the guide hole.
[0035] Further, refer to Figure 5 The pump body 51 is also equipped with a valve needle sleeve 40 opposite to the valve needle seat 30; the end of the valve needle 42 away from the valve needle seat 30 moves sequentially through the valve needle sleeve 40, the liquid storage chamber 7 and the liquid outlet 9 and is inserted into the glue injection chamber 10.
[0036] Further, refer to Figure 5 and Figure 8The hot runner needle valve cylinder 41 also includes a cylindrical second cavity 411b on its cylinder body 411. The hot runner needle valve cylinder 41 further includes a second cylinder front cover 415, a second piston 416, and a second piston rod 417. The second cylinder front cover 415 is fixedly connected to the opening end of the second cavity 411b and also has a guide hole. The second piston 416 is located inside the second cavity 411b and slides against the inner wall of the second cavity 411b. One end of the second piston rod 417 is fixedly connected to the second piston 416, and the other end extends through the guide hole of the second cylinder front cover 415 and is threaded with a counterscrew 50. The pump body 51 also includes a first safety channel 60, a second safety channel 70, a third safety channel 80, and a pressure regulating valve assembly 90. The first safety channel 60 is cylindrical and coaxially arranged with the counterscrew 50. One end of the second safety channel 70 is connected to the liquid outlet 9 and the liquid storage chamber. One end of the second safety channel 7 is connected to the outlet hole 9, and the other end is connected to the first safety channel 60. A cylindrical connecting channel 100 is provided between the second safety channel 70 and the first safety channel 60. The inner diameter of the connecting channel 100 is smaller than the inner diameter of the first channel, and a tapered second step is formed between the connecting channel 100 and the first channel. One end of the third safety channel 80 is connected to the first safety channel 60, and the other end is connected to the side of the liquid storage chamber 7 near the inlet hole 8. The pressure regulating valve assembly 90 includes a pressure regulating valve top rod 901 and a steel ball 902. One end of the pressure regulating valve top rod 901 is inserted into the first channel and slides against the inner wall of the first channel, and the other end is located outside the first channel and rests on the top screw 50. The steel ball 902 is located in the first channel and between the second step and the pressure regulating valve top rod 901. The diameter of the steel ball 902 is larger than the inner diameter of the connecting channel 100 and smaller than the inner diameter of the first safety channel 60. It should be noted that, similarly, the second piston 416 and the inner wall of the second cavity 411b also adopt a precise clearance fit, and the second piston rod 417 and the front cover 415 of the second cylinder are also equipped with corresponding seals. The pressure regulating valve top rod 901 and the inner wall of the first channel adopt a precise clearance fit. A sealing groove is set around the outer wall of the pressure regulating valve top rod 901, and a sealing ring is fitted inside the sealing groove to ensure that the pressure regulating valve top rod 901 and the inner wall of the first channel are tightly fitted, and to prevent the adhesive from seeping out along the gap between the pressure regulating valve top rod 901 and the first channel.
[0037] Furthermore, refer to Figure 5 and Figure 7The cylinder block 411 is also provided with a first intake channel 200, a second intake channel 300 and a third intake channel 400. The intake ports of the first intake channel 200, the second intake channel 300 and the third intake channel 400 are respectively connected to a first quick connector 210, a second quick connector 310 and a third quick connector 410. The first intake channel 200 is connected to the rodless chamber portion (i.e. the portion without the first piston rod 414) of the first cavity 411a. The second intake channel 300 is connected to the rod-bearing chamber portion (i.e. the portion with the first piston rod 414) of the first cavity 411a. The third intake channel 400 is connected to the rodless chamber portion (i.e. the portion without the second piston rod 417) of the second cavity 411b. The first quick connector 210, the second quick connector 310, and the third quick connector 410 are used to connect to the air source device, which provides compressed air to the cylinder 411. When compressed air is introduced into the rodless chamber of the first cavity 411a through the first quick connector 210, the air pressure pushes the first piston 413 forward. The first piston 413 and the first piston rod 414 drive the valve needle 42 forward, which can complete the sealing action of the injection port 101. When compressed air is introduced into the rodless chamber of the second cavity 411b through the second quick connector 310, the air pressure pushes the second piston 416 forward. The second piston 416 and the second piston rod 417 drive the counterscrew 50 forward. The counterscrew 50 presses against the pressure regulating valve rod 901, limiting the movement distance of the pressure regulating valve rod 901 and the steel ball 902.
[0038] When the integrated gun-pump-valve dispensing assembly is working, if the pressure in the dispensing chamber 10 of the dispensing gun 6 is too high, the adhesive material will be pushed back by the high pressure, causing the steel ball 902 to move away from the connecting channel 100. This creates a gap between the steel ball 902 and the connecting channel 100, allowing the adhesive material to flow back from the dispensing chamber 10 through the outlet hole 9, the second safety channel 70, and the connecting channel 100 to the first safety channel 60. Then, it will flow back through the first safety channel 60 and the third safety channel 80, and then back into the storage chamber 7 from the top side. This prevents the pressure in the dispensing chamber 10 from becoming too high and ensures the safety of the equipment. It should be noted that the intake pressure of the third intake channel 400 of the second chamber 411b of the cylinder 411 can be adjusted according to actual use. Specifically, it is adjusted by valve components in the air circuit between the air source and the third quick connector 410. By controlling the intake pressure of the third intake channel 400, the output thrust of the second piston rod 417 and the counterscrew 50 can be determined. When the pressure in the glue gun 6's glue injection chamber 10 is too high, the glue material pushes the steel ball 902 away from the connection due to the high pressure. When channel 100 moves, steel ball 902 pushes pressure regulating valve push rod 901 against the counterscrew 50. When the thrust of pressure regulating valve push rod 901 is greater than the output thrust set by second piston rod 417, second piston rod 417 will retract, and a gap will appear between steel ball 902 and connecting channel 100, allowing the adhesive to flow back. Conversely, when the thrust of pressure regulating valve push rod 901 is less than or equal to the output thrust set by second piston rod 417, steel ball 902 and connecting channel 100 will remain sealed, and the adhesive will not flow back.
[0039] In this embodiment, reference Figure 5 The glue gun 6 includes a glue gun sleeve 61 and a gun body 62 and a heating coil 63 installed inside the glue gun sleeve 61. One end of the gun body 62 is provided with a connector 621 that is inserted into the liquid outlet 9 of the pump body 51, and the other end is connected to a nozzle 622. A spacer 623 is coaxially installed inside the gun body 62. The glue injection cavity 10 is formed inside the spacer 623 and the nozzle 622. The heating coil 63 is arranged around the outside of the gun body 62.
[0040] In this embodiment, reference Figure 1 A fixed base 500 is fixedly connected to the bottom of the outer cylinder 1 of the glue cylinder. The fixed base 500 is provided with a connecting through hole that communicates with the first discharge port 12 of the outer cylinder 1 of the glue cylinder. The bottom end of the connecting through hole communicates with the liquid inlet connector 81 of the pump body 51. It should be noted that the bottom end of the connecting through hole can be directly connected to the liquid inlet connector 81 on the pump body 51, or it can be connected through a glue tube, and is not limited to this embodiment.
[0041] Optionally, the heater 3 includes a coil frame 31 and an induction coil 32. The coil frame 31 is sleeved on the outside of the glue cylinder outer cylinder 1 and fixedly connected to it. Multiple sets of wire grooves 311 are arranged around the outside of the coil frame 31, and the induction coil 32 is arranged around the outside of the coil frame 31 and inserted into the wire grooves 311. When an alternating current is passed through the induction coil, an alternating magnetic field is generated. As a metal conductor, the glue cylinder outer cylinder 1 generates eddy currents in the alternating magnetic field. The eddy currents generate heat inside the metal, thereby heating the glue cylinder outer cylinder 1. It should be noted that the glue melting cylinder assembly can adopt this electromagnetic heating structure, or other heating structures such as resistance heating structures, and is not limited to this embodiment.
[0042] Furthermore, the upper outer wall of the outer cylinder 1 of the glue cylinder is provided with a plurality of connecting ears 13 at intervals along the circumference. The connecting ears 13 are provided with connecting holes, and screws that are threadedly connected to the coil frame 31 pass through the connecting holes.
[0043] In summary, this utility model, by designing the melting cylinder assembly as a separate structure of the outer cylinder 1 and the inner cylinder 2, allows the inner cylinder 2 to be disassembled from the outer cylinder 1, making it easier to replace or clean the inner cylinder 2. Compared with traditional cylinders, it achieves weight reduction. The integrated gun-pump-valve injection assembly integrates a pressure regulating valve 4, a gear pump 5, and a glue gun 6. The gear pump 5 provides power to the glue gun 6, enabling the glue gun 6 to smoothly inject the glue into the cavity of the injection mold. The glue enters the storage chamber 7 from the inlet hole 8 of the pump body 51, and flows directly into the injection chamber 10 of the glue gun 6 through the storage chamber 7 and the outlet hole 9. The outlet hole 9 is directly connected to the glue gun 6, greatly shortening the flow path, ensuring smooth flow of the glue, reducing pressure loss, reducing glue blockage, and making the injection pressure more stable.
[0044] The above does not limit the technical scope of this utility model. Any modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of this utility model shall still fall within the scope of the technical solution of this utility model.
Claims
1. A low-pressure dispensing device, characterized in that: Includes an integrated glue injection assembly consisting of a melt cylinder assembly and a gun pump valve; The glue melting cylinder assembly includes an outer cylinder, an inner cylinder, and a heater. The inner wall of the outer cylinder has multiple sheet-like first heating grids evenly spaced circumferentially, and the bottom of the outer cylinder has a first discharge port. The inner cylinder is nested inside the outer cylinder, and its sidewalls have multiple second heating grids evenly spaced circumferentially. Each second heating grid is an inwardly protruding shell matching the shape of the first heating grids. The bottom of the inner cylinder has a second discharge port corresponding to the first discharge port. The heater is located outside the outer cylinder. The integrated gun-pump-valve dispensing assembly includes a pressure regulating valve, a gear pump, and a dispensing gun connected in sequence. The gear pump includes a pump body and a gear mechanism. The pump body has a liquid storage chamber, and the side wall of the pump body has an inlet hole communicating with the liquid storage chamber. The inlet hole is connected to an inlet connector. One end of the pump body has an outlet hole communicating with the liquid storage chamber. The gear mechanism is located in the liquid storage chamber and is used to drive the flow of the adhesive. The dispensing gun has a dispensing chamber. One end of the dispensing chamber is connected to the outlet hole, and the other end is a molding port. The pressure regulating valve includes a hot runner needle valve cylinder and a valve needle. The hot runner needle valve cylinder is mounted on the pump body. One end of the valve needle is connected to the hot runner needle valve cylinder, and the other end passes through the liquid storage chamber and the dispensing chamber, extending towards the molding port. The hot runner needle valve cylinder is used to drive the valve needle to perform linear reciprocating motion along the axial direction.
2. The low-pressure dispensing equipment according to claim 1, characterized in that: The pump body includes a gear pump sleeve and an upper cover, an intermediate body, and a lower cover sequentially installed inside the gear pump sleeve. The gear mechanism includes a drive shaft, a driven shaft, a drive gear, a driven gear, and a motor. One end of the drive shaft is rotatably connected to the lower cover, and the other end passes sequentially through the upper cover and the pressure regulating valve and is connected to the output end of the motor. The driven shaft is parallel to the drive shaft, and its two ends are rotatably connected to the upper cover and the lower cover, respectively. The drive gear and the driven gear are coaxially connected to the drive shaft and the driven shaft, respectively, and the drive gear meshes with the driven gear. A mounting base is fixedly connected to the bottom of the pressure regulating valve. The mounting base is used to install the motor on the equipment workbench.
3. The low-pressure dispensing equipment according to claim 1, characterized in that: The hot runner needle valve cylinder includes a cylinder body, a first cylinder front cover, a first piston, and a first piston rod. The cylinder body has a cylindrical first cavity. The first cylinder front cover is fixedly connected to the opening end of the first cavity. The first cylinder front cover has a guide hole. The first piston is located in the first cavity and slides against the inner wall of the first cavity. One end of the first piston rod is fixedly connected to the first piston, and the other end movably passes through the guide hole of the first cylinder front cover and is threadedly connected to a valve needle seat. The valve needle seat has a T-shaped through groove. The connection end of the valve needle with the hot runner needle valve cylinder has a cylindrical limiting head. The diameter of the limiting head is larger than the diameter of the valve needle, and an annular first step is formed between the limiting head and the side wall of the valve needle. The valve needle is connected to the T-shaped through groove through the limiting head.
4. The low-pressure dispensing equipment according to claim 3, characterized in that: The pump body is also equipped with a valve needle sleeve opposite to the valve needle seat; the end of the valve needle away from the valve needle seat moves sequentially through the valve needle sleeve, the liquid storage chamber and the liquid outlet and is inserted into the glue injection chamber.
5. A low-pressure dispensing device according to claim 3, characterized in that: The cylinder body also has a cylindrical second cavity. The hot runner needle valve cylinder further includes a second cylinder front cover, a second piston, and a second piston rod. The second cylinder front cover is fixedly connected to the opening end of the second cavity. The second cylinder front cover also has a guide hole. The second piston is located in the second cavity and slides against the inner wall of the second cavity. One end of the second piston rod is fixedly connected to the second piston, and the other end movably passes through the guide hole of the second cylinder front cover and is threaded with a counterscrew. The pump body also has a first safety channel, a second safety channel, a third safety channel, and a pressure regulating valve assembly. The first safety channel is cylindrical and coaxially arranged with the counterscrew. One end of the second safety channel is connected to the liquid outlet and the end of the liquid storage chamber near the liquid outlet. The second safety channel is connected to the first safety channel at one end and to the first safety channel at the other end. A cylindrical connecting channel is provided between the second safety channel and the first safety channel. The inner diameter of the connecting channel is smaller than the inner diameter of the first channel, and a tapered second step is formed between the connecting channel and the first channel. One end of the third safety channel is connected to the first safety channel, and the other end is connected to the side of the liquid storage chamber near the liquid inlet. The pressure regulating valve assembly includes a pressure regulating valve push rod and a steel ball. One end of the pressure regulating valve push rod is inserted into the first channel and slides against the inner wall of the first channel, while the other end is located outside the first channel and rests on the top screw. The steel ball is located in the first channel and between the second step and the pressure regulating valve push rod. The diameter of the steel ball is larger than the inner diameter of the connecting channel and smaller than the inner diameter of the first safety channel.
6. A low-pressure dispensing device according to claim 5, characterized in that: The cylinder block is also provided with a first intake channel, a second intake channel and a third intake channel. The intake ports of the first intake channel, the second intake channel and the third intake channel are respectively connected to a first quick connector, a second quick connector and a third quick connector. The first intake channel is connected to the rodless cavity portion of the first chamber, the second intake channel is connected to the rod cavity portion of the first chamber, and the third intake channel is connected to the rodless cavity portion of the second chamber.
7. The low-pressure dispensing equipment according to claim 1, characterized in that: The glue gun includes a glue gun sleeve and a gun body and a heating coil installed inside the glue gun sleeve. One end of the gun body is provided with a connector that plugs into the liquid outlet of the pump body, and the other end is connected to a nozzle. A spacer is coaxially installed inside the gun body. The glue injection cavity is formed inside the spacer and the nozzle. The heating coil is arranged around the outside of the gun body.
8. A low-pressure dispensing device according to claim 1, characterized in that: A fixed base is fixedly connected to the bottom of the outer cylinder of the glue cylinder. The fixed base is provided with a connecting through hole that communicates with the first discharge port of the outer cylinder of the glue cylinder. The bottom end of the connecting through hole is connected to the liquid inlet connector of the pump body.
9. A low-pressure dispensing device according to claim 1, characterized in that: The heater includes a coil frame and an induction coil. The coil frame is sleeved on the outside of the outer cylinder of the plastic cylinder and fixedly connected to the outer cylinder. Multiple sets of wire grooves are arranged around the outside of the coil frame. The induction coil is arranged around the outside of the coil frame and inserted into the wire grooves.
10. A low-pressure dispensing device according to claim 9, characterized in that: The upper outer wall of the outer cylinder of the glue cylinder is provided with multiple connecting lugs spaced circumferentially. Each connecting lug has a connecting hole, through which a screw is threaded to the coil skeleton.