Glue dispensing device with glue breaking control function and glue dispensing control method and glue dispensing equipment thereof

Abstract

The invention provides a dispensing device with a glue breaking control function and a dispensing control method and dispensing equipment thereof, and the method comprises the following steps: boosting and dispensing: increasing the air pressure in a glue cylinder to positive pressure P1, keeping the pressure unchanged, and extruding glue from a needle head by the positive pressure of the glue cylinder for dispensing; when dispensing is completed, the air pressure in the glue barrel is reduced from the positive pressure P1 to the negative pressure P2, the negative pressure P2 is smaller than the air pressure P3 in the glue barrel before dispensing, the negative pressure P2 is used for rapidly sucking the glue between the needle head and the workpiece back to the needle head, and the glue connection between the needle head and the workpiece is disconnected; and after the glue of the needle head is disconnected with the glue of the workpiece, the air pressure in the glue barrel is increased to P3 air pressure from negative pressure P2, and the glue on the needle head is kept in a static state in a gravity counteracting mode. According to the method, after pressure reduction and glue breaking, the glue is kept static relative to the needle head through small negative pressure, the phenomenon of thin tail caused by excessive glue on the surface of the workpiece and untimely glue suction is avoided, and the glue dispensing quality and the glue dispensing precision are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of glue dispensing, and in particular to a glue dispensing device with a glue cut-off control function, a glue dispensing control method and glue dispensing equipment. Background Art

[0002] A dispensing device is a device that controls a fluid (usually glue) and applies the fluid to the surface of a workpiece. Among them, a pneumatic dispensing valve is a commonly used dispensing device, which squeezes out the glue by delivering compressed air to the hose. The glue discharge flow rate is controlled by means of air pressure cut-off, negative pressure suction, etc. This dispensing control method makes the final glue output meet the product requirements by means of air pressure adjustment, flow control, air pressure suction, needle replacement, etc.

[0003] The control method of the above-mentioned pneumatic dispensing valve is relatively mature and is widely used in the application of various low-cost products, but this dispensing control method has certain limitations. Mainly manifested in that when dispensing needs to be stopped, due to the presence of a certain volume of compressed gas between the inside of the rubber cartridge and the pipeline connected to the rubber cartridge, it takes a certain amount of time to adjust the air pressure inside the rubber cartridge from positive pressure to negative pressure. During this period of time, although the air pressure in the rubber cartridge gradually decreases, the glue in the rubber cartridge still flows out through the needle. For example, when dispensing at a single dispensing point, the actual amount of glue flowing out will exceed the demand, and when dispensing by marking, a "thin tail" phenomenon will occur, which reduces the dispensing quality and makes it difficult to meet the high-precision dispensing process requirements.

[0004] Therefore, it is necessary to improve a dispensing device and a dispensing control method and a dispensing device in the prior art. Summary of the invention

[0005] In view of this, the purpose of the present invention is to overcome the defects existing in the prior art and provide a dispensing device with a glue cut-off control function and a dispensing control method and a dispensing device that improve the dispensing accuracy and dispensing quality.

[0006] In order to solve the above technical problems, the present invention provides a glue dispensing control method of a glue dispensing device with a glue breaking control function, comprising: Boost dispensing: Increase the air pressure in the glue cylinder to the positive pressure P1 and keep the pressure unchanged. The positive pressure of the glue cylinder squeezes the glue out of the needle for dispensing; Pressure reduction and glue disconnection: When glue dispensing is completed, the air pressure in the glue cylinder is reduced from positive pressure P1 to negative pressure P2, and the negative pressure P2 is less than the air pressure P3 in the glue cylinder before glue dispensing, which is used to quickly suck the glue between the needle and the workpiece back to the needle, and disconnect the glue connection between the needle and the workpiece; The P3 air pressure is a negative pressure or zero air pressure, and the P3 air pressure is used to make the glue stationary relative to the needle; the negative pressure P3 is greater than the negative pressure P2, and the suction force of the air pressure P2 is stronger; Glue suction by boosting pressure: when the glue on the needle is disconnected from the glue on the workpiece, the air pressure in the glue cylinder is increased from the negative pressure P2 to the P3 air pressure, so as to keep the glue on the needle in a stationary state by counteracting gravity.

[0007] Specifically, the step of dispensing also includes: Acquiring the moving path of the needle; Moving the needle to the starting point of the moving path; The glue is squeezed out from the needle while the needle moves along the moving path to the end position.

[0008] Specifically, the step of dispensing also includes: Get the location information of the dispensing position; Move the needle to the dispensing position; The glue is squeezed out from the needle and the needle remains stationary at the glue dispensing position.

[0009] Specifically, after the step of increasing the pressure and sucking the glue, the method further comprises: Stabilizing pressure and controlling glue: Keeping the air pressure in the glue cylinder constant is used to prevent glue from flowing out of the needle and wait for the next glue dispensing.

[0010] Specifically, after the step of increasing the pressure to absorb the glue, the glue at the needle tip is flush with the needle tip or slightly extends out of the needle tip.

[0011] The present invention also provides a glue dispensing device with a glue cut-off control function, which is used in the field of glue dispensing equipment, and includes a needle, a glue cartridge and an air pressure component. The needle and the air pressure component are respectively fixedly connected to the glue cartridge, and the air pressure component can generate positive pressure or negative pressure to squeeze out or suck back the glue in the glue cartridge from the needle; the air pressure component includes a positive pressure generator, a negative pressure generator and a first control valve. The glue cartridge, the positive pressure generator and the negative pressure generator are respectively connected to the first control valve, and the first control valve is used to control the gas flow between the glue cartridge and the positive pressure generator and the negative pressure generator.

[0012] Specifically, the first control valve is a three-way valve with three connectors, the second connector and the third connector of the first control valve are connected to the positive pressure generator and the negative pressure generator respectively, and the first connector of the first control valve is connected to the rubber cylinder, and is used to control the rubber cylinder to be connected to one of the positive pressure generator and the negative pressure generator, and disconnect the other one.

[0013] Specifically, the negative pressure generator is an adjustable air pressure generator, and the negative pressure generator includes a regulating part for switching the air pressure of the negative pressure generator.

[0014] Specifically, the negative pressure generator includes a first negative pressure generating circuit, a second negative pressure generating circuit and a second control valve; the first control valve, the first negative pressure generating circuit and the second negative pressure generating circuit are respectively connected to the second control valve; the negative pressure generated by the first negative pressure generating circuit is smaller than that of the second negative pressure generating circuit; the second control valve is used to control the gas flow between the first control valve and the first negative pressure generating circuit and the second negative pressure generating circuit to switch the air pressure of the negative pressure generator.

[0015] Specifically, the second control valve is a three-way valve with three connectors, the fifth connector and the sixth connector of the second control valve are respectively connected to the first negative pressure generating circuit and the second negative pressure generating circuit, and the third connector of the first control valve is connected to the fourth connector of the second control valve, which is used to control the third connector of the first control valve to be connected to one of the first negative pressure generating circuit and the second negative pressure generating circuit, and disconnect the other one.

[0016] Specifically, the dispensing device further includes a control system, which is connected to the first control valve and the second control valve and is used to switch the air pressure of the air pressure component.

[0017] The present invention also provides a glue dispensing device, comprising a glue dispensing device with a glue cut-off control function as described in any one of the above items.

[0018] In summary, compared with the prior art, the dispensing device with a glue-breaking control function and its dispensing control method and dispensing equipment of the present invention can quickly reduce the pressure in the glue cylinder to stop the glue output to break the glue, and then suck the glue back into the needle head to avoid excessive glue on the surface of the workpiece and the phenomenon of fine tail, thereby improving the dispensing quality and being suitable for high-precision dispensing. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0020] Figure 1 It is a process flow chart of the prior art.

[0021] Figure 2 It is a system schematic diagram of the prior art.

[0022] Figure 3 It is a curve diagram of the internal pressure of the rubber cylinder and time in the prior art.

[0023] Figure 4 It is a curve diagram of needle glue discharge speed and time in the prior art.

[0024] Figure 5 It is a schematic diagram of dispensing in the prior art.

[0025] Figure 6 It is a process flow chart of the present invention.

[0026] Figure 7 It is a system principle diagram of the present invention.

[0027] Figure 8 It is a curve diagram of the internal pressure of the rubber cylinder and time in the present invention.

[0028] Fig. 9 It is a curve diagram of the needle glue discharge speed and time in the present invention.

[0029] Fig.10 It is a schematic diagram of dispensing according to the present invention.

[0030] Fig.11 It is a working principle diagram of the control system of the present invention.

[0031] The reference numerals of the embodiments of the present invention in the above drawings are as follows: 1. Dispensing valve; 11. Glue cartridge; 12. Needle; 2. Positive pressure generator; 3. First negative pressure generating circuit; 4. Second negative pressure generating circuit; 5. First control valve; 6. Second control valve; 7. Control system; 8. Workpiece; 9. Negative pressure generator. DETAILED DESCRIPTION

[0032] The specific embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the description 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.

[0033] In the description of the present invention, unless otherwise clearly specified and limited, the terms "set", "install", "connection" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0034] The directions or positional relationships indicated by terms such as “upper”, “lower”, “left”, “right”, “front”, “back”, “top”, “bottom”, “inside” and “outside” are based on the directions or positional relationships shown in the accompanying drawings, or are the directions or positional relationships in which the inventive product is usually placed when used. They are only for the convenience of description and simplified description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0035] The terms "first", "second", "third", etc. are merely used to distinguish elements of similar nature, and do not indicate or imply relative importance or a particular order.

[0036] The terms "comprises," "comprising," or any other variations thereof, are intended to cover a non-exclusive inclusion of the elements listed and may also include additional elements not expressly listed.

[0037] The following is a detailed description through specific embodiments.

[0038] like Figure 1 As shown, the prior art dispensing control method includes the following steps: Step S1: Preparation, obtaining the dispensing path of the dispensing valve 1; Step S2: Boosting the pressure for glue dispensing, moving the glue dispensing valve 1 to the starting point of the glue dispensing path, increasing the air pressure in the glue cylinder 11 to P1, keeping the pressure unchanged, squeezing the glue out of the needle 12 and moving the glue dispensing valve 1 along the glue dispensing path to perform glue dispensing; Step S3: decompressing and cutting off the glue. When the glue dispensing valve 1 moves to the end of the glue dispensing path, the air pressure in the glue cylinder 11 is reduced to a negative pressure of P3, so as to reduce the glue dispensing speed of the needle 12 to 0; Step S4: Stabilize the pressure and control the glue, and maintain the negative pressure in the glue cylinder 11 at P3 to prevent the glue from flowing out of the needle 12.

[0039] Based on the above dispensing control method, the system structure principle diagram of the dispensing device in the prior art is as follows: Figure 2 As shown, including: The dispensing valve 1 comprises a rubber cylinder 11 and a needle 12 which are connected to each other; A first control valve 5, wherein an output end of the first control valve 5 is connected to the rubber cylinder 11; A positive pressure generator 2 and a negative pressure generator 9 are connected to two input ends of the first control valve 5, respectively, wherein the positive pressure generator 2 is used to adjust the air pressure in the rubber cylinder 11 to a positive pressure of P1, so as to input compressed air into the rubber cylinder 11, squeeze the glue through the needle 12, and dispense glue on the surface of the workpiece 8; the negative pressure generator 9 is used to adjust the air pressure in the rubber cylinder 11 to a negative pressure of P3, so as to reduce the glue discharging speed of the needle 12 to 0; specifically, the positive pressure generator 2 is a glue discharging pressure adjustment valve, and the negative pressure generator 9 is a back-suction negative pressure generator; The control system 7 is electrically connected to the first control valve 5, the negative pressure generator 9 and the positive pressure generator 2 to control the actions of the first control valve 5, the negative pressure generator 9 and the positive pressure generator 2.

[0040] After adopting the above-mentioned dispensing control method and structure, when dispensing, the curve diagram of the pressure inside the glue cylinder 11 and time is as follows: Figure 3 As shown, the curve diagram of the glue discharge speed of the needle 12 and time is as follows Figure 4 As shown, at time t0, the control system 7 controls the first control valve 5 to operate and the positive pressure generator 2 to start, so that the positive pressure generator 2 injects compressed air into the rubber cylinder 11 through the first control valve 5 until the air pressure in the rubber cylinder 11 rises to P1 and remains there until time t1.

[0041] During the above time period, the air pressure in the rubber cylinder 11 first rises from P3 to P1, and then maintains at the level of P1, and the glue discharge speed of the needle 12 first rises from 0 to v1, and then maintains at a stable level of v1, so that the needle 12 squeezes the glue to dispense on the surface of the workpiece 8.

[0042] When the dispensing valve 1 moves to the end point of the dispensing path, the control system 7 controls the first control valve 5 and the negative pressure generator 9 to operate, so that the negative pressure generator 9 is connected to the rubber cylinder 11 through the first control valve 5, and the positive pressure generator 2 is disconnected from the rubber cylinder 11, thereby extracting the air in the rubber cylinder 11, so that the air pressure in the rubber cylinder 11 gradually decreases, and finally forms a negative pressure of P3. At the same time, the glue discharge speed of the needle 12 is 0.

[0043] When performing the operation of step S3, Figure 3 and Figure 4 As shown in FIG. 1 , from time t1 to time t2, the pressure in the rubber cylinder 11 gradually decreases from P1 to P3, and the glue dispensing speed gradually decreases from v1 to 0. Since there is a long time from t1 to t2, a long thin tail is easily formed on the surface of the workpiece 8 at the final moment of dispensing, as shown in FIG. Figure 5 As shown, the dispensing quality and accuracy are reduced, so it is not suitable for high-precision dispensing occasions.

[0044] In the prior art, in order to minimize the tail phenomenon, it is necessary to stop outputting glue and quickly cut off the glue in a shorter time, that is, less than t2-t1. This requires increasing the suction force (negative pressure value) to minimize the volume of the sucked air. However, increasing the suction force will easily cause the glue to be sucked back into the needle 12 and the air to enter the needle 12 and mix with the glue, which cannot meet the process requirements.

[0045] Based on the above factors, the present invention provides a glue dispensing device with glue cut-off control function and its glue dispensing control method and glue dispensing equipment, as shown below.

[0046] like Figure 6 As shown, an embodiment of the present invention provides a dispensing control method of a dispensing device with a dispensing cut-off control function, comprising: Step S1: Boosting pressure for dispensing: increasing the air pressure in the glue cylinder 11 to a positive pressure P1 and then keeping the pressure constant. The positive pressure of the glue cylinder 11 squeezes the glue out of the needle 12 for dispensing; Step S2: Depressurization and glue cutting: When glue dispensing is completed, the air pressure in the rubber cylinder 11 is reduced from positive pressure P1 to negative pressure P2, and the negative pressure P2 is less than the air pressure P3 in the rubber cylinder 11 before glue dispensing (the air pressure P3 corresponds to Figure 8 The negative pressure P3 in the workpiece (the negative pressure P3 is greater than the negative pressure P2, and the suction force of the air pressure P2 is stronger) is used to quickly suck the glue between the needle 12 and the workpiece back to the needle 12, and disconnect the glue connection between the needle 12 and the workpiece; Step S3: Boosting the pressure to suck glue: When the glue on the needle 12 is disconnected from the glue on the workpiece, the air pressure in the glue cylinder 11 is increased from the negative pressure P2 to the pressure P3, so as to keep the glue on the needle in a static state by counteracting gravity. Specifically, the glue is sucked back to protrude outside the bottom end of the needle 12 or flush with the bottom end of the needle 12.

[0047] In this embodiment, the positive and negative values ​​of the air pressure represent the direction of the airflow. Positive pressure indicates that the airflow (glue) flows from the rubber cylinder 11 to the needle 12, and negative pressure indicates that the airflow (glue) flows from the rubber cylinder 11 to the needle 12. The absolute value of the air pressure (i.e., the size of the value) represents the speed of the airflow (the size of the pressure). The greater the air pressure, the faster the flow speed of the airflow (the movement speed of the glue).

[0048] After adopting the above improvements, since the negative pressure P2 is less than the P3 air pressure, when the dispensing valve 1 reaches the key position of the dispensing path and stops dispensing, the negative pressure attraction increases. The time to stop dispensing is greatly shortened. After stopping dispensing, the glue dispensing speed of the needle 12 is 0, and then the air pressure in the rubber cylinder 11 is raised to the negative pressure of the P3 air pressure. The glue changes from flowing downward to flowing upward, so that the flow direction of the glue changes, so that part of the glue that has been discharged from the needle 12 is sucked back. The glue connected to the needle 12 is quickly separated from the glue applied to the workpiece 8, so as to achieve the purpose of rapid glue cutting. Due to the viscosity of the glue when cutting off the glue, part of the glue outside the needle 12 will be "pulled" to the surface of the workpiece 8, filling the amount of glue in the rubber cylinder 11 during the time period when the negative pressure drops from P1 to P2, thereby improving the fine tail phenomenon and improving the dispensing accuracy and quality.

[0049] After the glue is cut off, the air pressure in the rubber cylinder 11 rises to the negative pressure of the P3 air pressure. At this stage, the glue flows back, rising from 0 to a certain speed and then slowing down until it stops, and finally sucked back into the needle 12.

[0050] In this embodiment, the P3 air pressure is negative pressure or zero pressure, and the P3 air pressure is used to make the glue stationary relative to the needle 12. Specifically, some glues are fluid and easily drip from the needle 12, so the P3 air pressure is preferably a negative pressure with a smaller pressure to absorb the glue and prevent it from dripping.

[0051] In this embodiment, the step of dispensing glue further includes: Step S11: obtaining the moving path of the needle 12; Step S12: moving the needle 12 to the starting position of the moving path; Step S13: The glue is squeezed out from the needle 12 while the needle 12 moves along the moving path to the end position.

[0052] In another implementation of this embodiment, the step of dispensing glue further includes: Step S11: obtaining the position information of the dispensing position; Step S12: moving the needle 12 to the dispensing position; Step S13: The glue is squeezed out from the needle 12 while the needle 12 remains at the glue dispensing position.

[0053] In this embodiment, after the step of increasing pressure and sucking glue, the method further includes: Step S4: stabilizing the pressure and controlling the glue: maintaining the air pressure in the glue cylinder 11 unchanged to prevent the glue from flowing out of the needle 12 and waiting for the next glue dispensing.

[0054] In this embodiment, after the step of boosting the pressure to absorb the glue, the glue at the needle 12 is flush with the needle 12 or slightly protrudes from the needle 12. The bottom of the glue is flush with the bottom of the needle 12, so that the glue is prevented from protruding from the bottom of the needle 12. This can prevent the problem of excessive glue at the beginning of glue dispensing due to the glue protruding from the bottom of the needle 12, which reduces the glue dispensing accuracy in the subsequent glue dispensing process.

[0055] like Figure 7 As shown, an embodiment of the present invention also provides a glue dispensing device with a glue cut-off control function, which is used in the field of glue dispensing equipment, and includes a needle 12, a glue cartridge 11 and a pneumatic component. The needle 12 and the pneumatic component are respectively fixedly connected to the glue cartridge 11, and the pneumatic component can generate positive pressure or negative pressure to squeeze or suck back the glue in the glue cartridge 11 from the needle 12.

[0056] Specifically, the air pressure component has positive pressure P1, negative pressure P2 and P3 air pressure ( Figure 8 The pneumatic component can switch between the three working states: negative pressure P3 and negative pressure P4.

[0057] In this embodiment, the air pressure component includes a positive pressure generator 2, a negative pressure generator 9 and a first control valve 5. The rubber cartridge 11, the positive pressure generator 2 and the negative pressure generator 9 are respectively connected to the first control valve 5. The first control valve 5 is used to control the gas flow between the rubber cartridge 11 and the positive pressure generator 2 and the negative pressure generator 9.

[0058] Specifically, the air pressure generated by the positive pressure generator 2 is a positive pressure P1, and the air pressure generated by the negative pressure generator 9 is a negative pressure P2 or P3 ( Figure 8 The first control valve 5 is used to control the pneumatic component to switch between these three working states.

[0059] In this embodiment, the first control valve 5 is a three-way valve with three connectors. The second connector and the third connector of the first control valve 5 are connected to the positive pressure generator 2 and the negative pressure generator 9 respectively. The first connector of the first control valve 5 is connected to the rubber cartridge 11, and is used to control the rubber cartridge 11 to be connected to one of the positive pressure generator 2 and the negative pressure generator 9, and the other is disconnected. The second connector is an input end, and the gas is input from the positive pressure generator 2 to the first control valve; the third connector is an output end, and the gas is output from the first control valve 5 to the negative pressure generator 9; the first connector is an output end or an input end. When the rubber cartridge 11 is connected to the positive pressure generator 2, the first connector is an output end, and when the rubber cartridge 11 is connected to the negative pressure generator 9, the first connector is an input end.

[0060] In this embodiment, the negative pressure generator 9 is an adjustable air pressure generator, and the negative pressure generator 9 includes a regulating part for switching the air pressure of the negative pressure generator 9 .

[0061] In another implementation of the present embodiment, the negative pressure generator 9 includes a first negative pressure generating circuit 3, a second negative pressure generating circuit 4 and a second control valve 6; the first control valve 5, the first negative pressure generating circuit 3 and the second negative pressure generating circuit 4 are respectively connected to the second control valve 6; the negative pressure generated by the first negative pressure generating circuit 3 is less than that of the second negative pressure generating circuit 4; the second control valve 6 is used to control the gas flow between the first control valve 5 and the first negative pressure generating circuit 3 and the second negative pressure generating circuit 4 to switch the air pressure of the negative pressure generator 9.

[0062] Specifically, the air pressure generated by the first negative pressure generating circuit 3 is negative pressure P2, and the air pressure generated by the second negative pressure generating circuit 4 is P3 air pressure ( Figure 8 The second control valve 6 is used to control the magnitude of the air pressure output by the negative pressure generator 9 to the first control valve 5.

[0063] In this embodiment, the second control valve 6 is a three-way valve with three connectors. The fifth connector and the sixth connector of the second control valve 6 are connected to the first negative pressure generating circuit 3 and the second negative pressure generating circuit 4 respectively. The third connector of the first control valve 5 is connected to the fourth connector of the second control valve 6, which is used to control the first control valve 5 to be connected to one of the first negative pressure generating circuit 3 and the second negative pressure generating circuit 4, and disconnect the other. The fifth connector and the sixth connector are both output ends, and the gas is output from the second control valve 6 to the first negative pressure generating circuit 3 or the second negative pressure generating circuit 4; the fourth connector is an input end, and the gas is input from the first control valve 5 to the second control valve 6.

[0064] Specifically, when the first control valve 5 controls the rubber cylinder 11 to be connected to the positive pressure generator 2, the air pressure output by the air pressure component is the positive pressure P1; when the first control valve 5 controls the rubber cylinder 11 to be connected to the second control valve 6, if the second control valve 6 controls the first control valve 5 to be connected to the first negative pressure circuit 3 at this time, the air pressure output by the air pressure component is the negative pressure P2; if the second control valve 6 controls the first control valve 5 to be connected to the second negative pressure circuit 4 at this time, the air pressure output by the air pressure component is the P3 air pressure ( Figure 8 The structure of the air pressure assembly can conveniently and accurately adjust the pressure in the rubber cylinder 11 to the value P3. Specifically, in the three working states, the pressure in the rubber cylinder 11 is adjusted to P1, P2 and P3 air pressure (P3) through the three air pressure generating ends and the two control valves, so as to perform the dispensing, cutting and sucking back operations respectively.

[0065] In this embodiment, the glue dispensing device with glue cut-off control function further includes a control system 7, which is connected to the first control valve 5 and the second control valve 6 and is used to switch the air pressure of the air pressure component.

[0066] In this embodiment, the glue dispensing device with glue cut-off control function further includes a control system 7, which is connected to the first control valve 5 and the second control valve 6 and is used to switch the air pressure of the air pressure component.

[0067] Specifically, the first control valve 5, the second control valve 6 and the three air pressure generating ends (positive pressure generator 2, first negative pressure generating circuit 3, second negative pressure generating circuit 4) are all controlled by the control system 7. After adopting the above structure, the control system 7 controls the connection and disconnection of the positive pressure generator 2, the first negative pressure generating circuit 3 and the second negative pressure generating circuit 4 with the rubber cylinder 11 by controlling the on and off of the first control valve 5 and the second control valve 6. The working state of the air pressure component is adjusted and switched, so as to achieve the effect of quickly adjusting the air pressure in the rubber cylinder 11, thereby improving the dispensing quality and accuracy.

[0068] After adopting the above-mentioned dispensing control method and the dispensing device with the dispensing control function, the dispensing valve 1 can be divided into multiple stages when dispensing, such as Figure 8 and Fig. 9 As shown (by default, dispensing valve 1 is already at the starting point of the dispensing path at time t0): 1. The first stage, i.e. the dispensing stage, is from t0 to t1. The control system 7 controls the first control valve 5 to operate, and the positive pressure generator 2 is started at the same time. The positive pressure generator 2 is connected to the rubber cylinder 11 through the first control valve 5, so that the pressure in the rubber cylinder 11 is quickly increased to the positive pressure P1, and the pressure is kept constant. During the pressure rise process, the glue dispensing speed of the needle 12 increases from 0 to v1, and the glue dispensing direction of the needle 12 is downward, so as to dispense glue on the surface of the workpiece 8.

[0069] 2. The second stage, that is, the glue-breaking stage, is from t1 to t3. The control system 7 controls the first control valve 5 and the second control valve 6 to operate, and the first negative pressure generating circuit 3 is started at the same time. The first negative pressure generating circuit 3 is connected to the rubber cylinder 11, and the pressure in the rubber cylinder 11 is rapidly reduced to the negative pressure of P2. At t3, the glue-discharging speed of the needle 12 is reduced to 0. However, part of the glue outside the needle 12 is still disconnected from the glue on the surface of the workpiece 8. Due to the viscosity of the glue during glue-breaking, part of the glue outside the needle 12 will be "pulled" to the surface of the workpiece 8, improving the thin tail phenomenon. Since P2 is less than P3, that is, the output negative pressure of the first negative pressure generating circuit 3 is lower than the output negative pressure of the second negative pressure generating circuit 4, so that (t3-t1) < (t2-t1), the air pressure in the rubber cylinder 11 can be quickly reduced, and the glue-discharging stop time is greatly shortened. In addition, during the process of stopping glue discharging, the glue is disconnected due to the rapid reduction of the air pressure in the rubber cylinder 11.

[0070] 3. The third stage, that is, the back-suction stage, the specific time is from moment t3 to moment t4. The control system 7 maintains the state of the first control valve 5, and controls the action of the second control valve 6, and at the same time the second negative pressure generating circuit 4 is started. The second negative pressure generating circuit 4 is connected to the rubber cylinder 11, and the pressure in the rubber cylinder 11 is raised to the negative pressure of P3 until moment t4. In this process, the glue flows back upward, and the speed first increases from 0, and then decreases to 0. When the glue speed decreases to 0 again, it is moment t4. At this time, the glue is sucked back into the needle 12, and the bottom of the sucked-back glue part is flush with the bottom of the needle 12, avoiding air mixing in the needle 12 and affecting the quality of the glue. At the same time, it also avoids the problem that the glue is exposed to the needle 12, resulting in excessive glue in the initial stage of the subsequent dispensing process, thereby affecting the subsequent dispensing quality.

[0071] 4. The fourth stage, namely the anti-backflow stage, is after time t4. The control system 7 controls the second negative pressure generating circuit 4 to keep running, so as to maintain the negative pressure in the rubber cylinder 11 at P3 to prevent glue from dripping.

[0072] After the above four stages, when the dispensing valve 1 of the present invention dispenses glue on the surface of the workpiece 8, the schematic diagram is as shown in FIG. Fig.10 As shown, Figure 5 Compared with the dispensing operation of the dispensing valve 1 of the prior art, the "thin tail" phenomenon occurring during the dispensing process can be significantly improved, thereby improving the dispensing quality and further meeting the high-precision dispensing requirements.

[0073] like Fig.11 As shown in the figure, it is the working principle under different working conditions, where the arrow is the flow direction of the gas, and the arrow issued by the control system 7 represents the control signal. The working principle of the control system 7 is as follows: (1) If Fig.11 As shown in (a), the initial state is: all negative pressure generators 9 and positive pressure generators 2 are turned on, the second control valve 6 is connected to the second negative pressure generating circuit 4, and the first control valve 5 is connected to the second control valve 6 and the rubber cylinder 11; this is equivalent to the second negative pressure generating circuit 4 and the rubber cylinder 11 being connected, and the negative pressure P3 acts on the glue to prevent the glue from flowing out due to gravity; (2) If Fig.11 As shown in (b), when the control system 7 receives the external dispensing control signal, it drives the first control valve 5, switches the first control valve 5 to be connected with the positive pressure generator 2 and the rubber cylinder 11, and the positive pressure P1 is connected to the rubber cylinder, and the glue in the rubber cylinder is squeezed out from the needle head under pressure; (3) If Fig.11As shown in (c), after the above switching is completed, the second control valve 6 is switched to be connected with the first negative pressure generating circuit 3 and the first control valve 5, in preparation for stopping dispensing; at this time, since the first control valve 5 is connected with the positive pressure generator 2 and the rubber cylinder 11, the second negative pressure generating circuit 4 and the first negative pressure generating circuit 3 are both inoperative; (4) If Fig.11 As shown in (d), when the control system 7 receives the external signal to stop dispensing glue, it drives the first control valve 5 and switches the first control valve 5 to be connected with the second control valve 6 and the rubber cylinder 11; at this time, since the second control valve 6 is connected with the first negative pressure generating circuit 3 and the first control valve 5, the negative pressure P2 of the first negative pressure generating circuit 3 acts on the rubber cylinder 11. Under the action of the larger negative pressure P2 (the suction force is greater than the negative pressure P3), the glue stops dispensing quickly and starts to flow in the reverse direction, disconnecting the glue from the workpiece; (5) Fig.11 As shown in (e), after the set time, the control system 7 controls the second control valve 6 to switch, and switches the second control valve 6 to be connected with the second negative pressure generating circuit 4 and the first control valve 5, and the negative pressure P3 of the second negative pressure generating circuit 4 acts on the rubber cylinder 11 to realize the glue back suction control (offsetting the influence of the gravity of the glue and stopping the flow); (6) Maintain the current state and wait for the next dispensing signal to arrive; (7) The control system 7 can adjust the glue cut-off and reflux flow by controlling the pressure and action time of the first negative pressure generating circuit 3; (8) The control system 7 controls the pressure of the second negative pressure generating circuit 4 to offset the glue overflow caused by the gravity of the glue in the glue cylinder; (9) The control system 7 controls the glue output speed and glue output amount by controlling the size and action time of the positive pressure.

[0074] An embodiment of the present invention further provides a glue dispensing device, comprising a glue dispensing device with a glue cut-off control function as described in any of the above items.

[0075] In summary, compared with the prior art, the dispensing device with glue cut-off control function and its dispensing control method and dispensing equipment of the present invention quickly reduce the pressure in the glue cylinder 11 to stop the glue output to cut off the glue, and then suck the glue back into the needle head to avoid excessive glue on the surface of the workpiece and the phenomenon of fine tail, thereby improving the dispensing quality and being suitable for high-precision dispensing.

[0076] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the attached claims.

Claims

1. A glue dispensing control method for a glue dispensing device with a glue cut-off control function, characterized in that: include: Boost dispensing: Increase the air pressure in the glue cylinder to the positive pressure P1 and keep the pressure unchanged. The positive pressure of the glue cylinder squeezes the glue out of the needle for dispensing; Pressure reduction and glue disconnection: When glue dispensing is completed, the air pressure in the glue cylinder is reduced from positive pressure P1 to negative pressure P2, and the negative pressure P2 is less than the air pressure P3 in the glue cylinder before glue dispensing, which is used to quickly suck the glue between the needle and the workpiece back to the needle, and disconnect the glue connection between the needle and the workpiece; The P3 air pressure is a negative pressure or zero air pressure, and the P3 air pressure is used to make the glue stationary relative to the needle; the negative pressure P3 is greater than the negative pressure P2, and the suction force of the air pressure P2 is stronger; Glue suction by boosting pressure: when the glue on the needle is disconnected from the glue on the workpiece, the air pressure in the glue cylinder is increased from the negative pressure P2 to the P3 air pressure, so as to keep the glue on the needle in a stationary state by counteracting gravity.

2. The glue dispensing control method of the glue dispensing device with glue cut-off control function according to claim 1, characterized in that: The step of dispensing also includes: Acquiring the moving path of the needle; Moving the needle to the starting point of the moving path; The glue is squeezed out from the needle while the needle moves along the moving path to the end position.

3. The glue dispensing control method of the glue dispensing device with glue cut-off control function according to claim 1, characterized in that: The step of dispensing also includes: Get the location information of the dispensing position; Move the needle to the dispensing position; The glue is squeezed out from the needle and the needle remains stationary at the glue dispensing position.

4. The glue dispensing control method of the glue dispensing device with glue cut-off control function according to claim 1, characterized in that: The step of boosting the pressure and sucking the glue further comprises: Stabilizing pressure and controlling glue: Keeping the air pressure in the glue cylinder constant is used to prevent glue from flowing out of the needle and wait for the next glue dispensing.

5. The glue dispensing control method of the glue dispensing device with glue cut-off control function according to claim 1, characterized in that: After the step of increasing the pressure to absorb the glue, the glue at the needle tip is flush with the needle tip or slightly extends out of the needle tip.

6. A glue dispensing device with glue cut-off control function, used in the field of glue dispensing equipment, characterized in that: It includes a needle, a rubber cartridge and an air pressure component, wherein the needle and the air pressure component are fixedly connected to the rubber cartridge respectively, and the air pressure component can generate positive pressure or negative pressure, which is used to squeeze out or suck back the glue in the rubber cartridge from the needle; the air pressure component includes a positive pressure generator, a negative pressure generator and a first control valve, wherein the rubber cartridge, the positive pressure generator and the negative pressure generator are connected to the first control valve respectively, and the first control valve is used to control the gas flow between the rubber cartridge and the positive pressure generator and the negative pressure generator.

7. The glue dispensing device with glue cut-off control function according to claim 6, characterized in that: The first control valve is a three-way valve with three connectors, the second connector and the third connector of the first control valve are connected to the positive pressure generator and the negative pressure generator respectively, and the first connector of the first control valve is connected to the rubber cylinder, which is used to control the rubber cylinder to be connected to one of the positive pressure generator and the negative pressure generator and disconnect the other one.

8. The glue dispensing device with glue cut-off control function as claimed in claim 6, characterized in that: The negative pressure generator is an adjustable air pressure generator, and the negative pressure generator comprises a regulating part for switching the air pressure of the negative pressure generator.

9. The glue dispensing device with glue cut-off control function according to claim 6, characterized in that: The negative pressure generator includes a first negative pressure generating circuit, a second negative pressure generating circuit and a second control valve; the first control valve, the first negative pressure generating circuit and the second negative pressure generating circuit are respectively connected to the second control valve; the negative pressure generated by the first negative pressure generating circuit is smaller than that of the second negative pressure generating circuit; the second control valve is used to control the gas flow between the first control valve and the first negative pressure generating circuit and the second negative pressure generating circuit to switch the air pressure of the negative pressure generator.

10. The glue dispensing device with glue cut-off control function according to claim 9, characterized in that: The second control valve is a three-way valve with three connectors, the fifth connector and the sixth connector of the second control valve are connected to the first negative pressure generating circuit and the second negative pressure generating circuit respectively, and the third connector of the first control valve is connected to the fourth connector of the second control valve, which is used to control the third connector of the first control valve to be connected to one of the first negative pressure generating circuit and the second negative pressure generating circuit, and disconnect the other one.

11. The glue dispensing device with glue cut-off control function according to claim 9, characterized in that: The dispensing device also includes a control system, which is connected to the first control valve and the second control valve and is used to switch the air pressure of the air pressure component.

12. A dispensing device, characterized in that: It comprises a glue dispensing device with a glue cut-off control function as described in any one of claims 6-11.

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