Quantitative pump

Abstract

The utility model discloses a metering pump which comprises a driving assembly, a stock bin, a stop valve assembly, a glue gun assembly and a control assembly, the driving assembly comprises a first driving piece, a planetary ball screw, a planetary nut, a guide structure and a piston rod structure, and the stock bin comprises a first glue cavity, a feeding channel and a discharging channel. The feeding channel communicates with the discharging channel through the first rubber cavity, an output shaft of the first driving part is connected with the planetary ball screw, the planetary nut is arranged on the peripheral side of the planetary ball screw in a sleeving mode and connected with the guiding structure, and one end of the piston rod structure is arranged at the end, away from the first driving part, of the planetary ball screw in a sleeving mode and connected with the planetary nut. The other end of the piston rod structure is located in the first glue cavity so that the piston rod structure can be driven by the first driving part to reciprocate in the first glue cavity, the stop valve assembly and the glue gun assembly are installed on the stock bin, the stop valve assembly is communicated with the feeding channel, the glue gun assembly is communicated with the discharging channel, and the control assembly is connected with the stop valve assembly and the glue gun assembly.

Description

Technical Field

[0001] The utility model relates to the technical field of glue coating equipment, in particular to a quantitative pump. Background Art

[0002] In the gluing process of modern automobile manufacturing, manual handheld glue guns are usually used to apply glue to automobile workpieces. This gluing process is extremely dependent on the skill level and experience of the operator. It is difficult to control the gluing, which can easily cause unstable glue application and cannot ensure that the thickness and shape of the glue layer applied on each product are completely consistent. In addition, due to frequent manual operations, workers consume a lot of physical energy, and long-term repetitive operations can easily cause fatigue and reduced efficiency. Utility Model Content

[0003] The technical problem to be solved by the utility model is that the existing glue coating adopts manual handheld glue gun spraying, which easily causes the phenomenon of unstable glue coating amount, cannot ensure that the thickness and shape of the glue layer coated on each product are completely consistent, and has high work intensity.

[0004] In order to solve the above technical problems, the utility model provides a quantitative pump, including a driving component, a silo, a stop valve component, a glue gun component and a control component, the driving component including a first driving member, a planetary ball screw, a planetary nut, a guide structure and a piston rod structure, the silo includes a first glue chamber, a feed channel and a discharge channel, the feed channel is connected with the discharge channel through the first glue chamber, the output shaft of the first driving member is connected with the planetary ball screw, the planetary nut is sleeved on the peripheral side of the planetary ball screw, and the planetary nut is connected with the guide structure, one end of the piston rod structure is sleeved on one end of the planetary ball screw away from the first driving member, and is connected with the planetary nut, the other end of the piston rod structure is located in the first glue chamber, so as to drive the piston rod structure to reciprocate in the first glue chamber through the first driving member, the stop valve component and the glue gun component are installed on the silo, and the stop valve component is communicated with the feed channel, the glue gun component is communicated with the discharge channel, and the control component is connected with the stop valve component and the glue gun component.

[0005] Furthermore, it also includes a fixed seat with an installation cavity, the guide structure includes a nut seat and a plurality of connecting rods, the first driving member is connected to the fixed seat, the planetary ball screw passes through the fixed seat and extends into the installation cavity, the plurality of connecting rods are installed in the installation cavity at intervals around the axis of the planetary ball screw, the nut seat is movably connected to the connecting rod, and the planetary nut is installed on the nut seat.

[0006] Furthermore, the piston rod structure includes a piston rod, a sealing cover, a sealing ring and a connecting seat, the connecting seat is connected to the planetary nut, one end of the piston rod is connected to the connecting seat, and the other end of the piston rod is connected to the sealing cover, and the sealing ring is sleeved on one end of the piston rod close to the sealing cover.

[0007] Further, the silo also includes a sealing port, the stop valve assembly includes a second driving member, a first valve seat and a first heating device, the second driving member and the first heating device are installed on the first valve seat, the first valve seat has a second glue cavity and a glue inlet connected to the second glue cavity, the first valve seat is connected to the silo, and the second glue cavity is connected to the first glue cavity, the second driving member includes a first driving unit and a first valve stem, the first valve stem is located in the second glue cavity, and the output shaft of the first driving unit is connected to one end of the first valve stem to drive the other end of the first valve stem to approach or move away from the sealing port.

[0008] Furthermore, the first drive unit also includes a first cylinder body, a first valve core, a first wave spring and a first connecting end. The first valve core is movably arranged in the first cylinder body to form a first pneumatic chamber with the first cylinder body. One end of the first valve stem passes through the first cylinder body and is connected to the first valve core. The first wave spring is arranged in the first pneumatic chamber, and the two ends of the first wave spring are respectively abutted against the inner wall of the first cylinder body and the outer wall of the first valve core. The first connecting end is installed on the first cylinder body and is connected to the first pneumatic chamber.

[0009] Furthermore, it also includes a pressure sensor for detecting the pressure of the first glue cavity, and the pressure sensor is installed in the silo.

[0010] Further, the glue gun assembly includes a third driving member, a second valve seat, a glue feed seat, a heating tube, a glue spray head and a second heating device. The glue feed seat is installed on the silo, and the second valve seat is connected to the side of the glue feed seat away from the silo. The heating tube, the third driving member and the second heating device are installed on the second valve seat, and the glue spray head is installed at one end of the heating tube away from the second valve seat. The third driving member includes a second driving unit and a second valve stem. One end of the second valve stem is connected to the output shaft of the second driving unit, and the other end passes through the second valve seat and the heating tube in sequence to seal or open the glue spray head through the drive of the third driving member.

[0011] Furthermore, the second driving unit also includes a second cylinder body, a second valve core, a second wave spring and a second connecting end. The second valve core is movably arranged in the second cylinder body to form a second pneumatic chamber with the second cylinder body. One end of the second valve stem passes through the second cylinder body and is connected to the second valve core. The second wave spring is arranged in the second pneumatic chamber, and the two ends of the second wave spring are respectively abutted against the inner wall of the second cylinder body and the outer wall of the second valve core. The second connecting end is installed on the second cylinder body and is connected to the second pneumatic chamber.

[0012] Furthermore, the control assembly includes an air control unit, and the air control unit is connected to the stop valve assembly and the glue gun assembly.

[0013] Furthermore, it also includes a reducer, and the first driving member and the planetary ball screw are connected through the reducer.

[0014] Compared with the prior art, the metering pump of the utility model has the following beneficial effects:

[0015] The first driving member of the embodiment of the utility model is connected to the planetary ball screw through the output shaft to convert the rotational motion of the first driving member into linear reciprocating motion. When the first driving member drives the planetary ball screw to rotate, the planetary screw nut can move along the axial direction of the planetary ball screw, and the guide structure ensures the stability of its linear motion trajectory. With the movement of the planetary screw nut, the piston rod structure will reciprocate in the first glue chamber, thereby completing the process of sucking and pushing glue. This embodiment realizes precise control of the glue flow rate through the above process, solves the problem of unstable spraying of manual hand-held glue guns, and ensures that the glue coating task can be completed automatically and efficiently in the glue coating process through precise mechanical transmission, thereby improving product quality and production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of a metering pump provided in an embodiment of the utility model;

[0017] Figure 2 It is provided along the embodiment of the utility model Figure 1 Cross-sectional view in the AA direction;

[0018] Figure 3 The utility model embodiment provides Figure 2 A partial enlarged view of the circled portion A;

[0019] Figure 4 The utility model embodiment provides Figure 2 A partial enlarged view of the circled portion B;

[0020] Figure 5 The utility model embodiment provides Figure 2 A partial enlarged view of the circled portion C;

[0021] In the figure, 1, drive assembly; 11, first drive member; 12, planetary ball screw; 13, planetary nut; 14, guide structure; 141, nut seat; 142, connecting rod; 15, piston rod structure; 151, piston rod; 152, sealing gland; 153, sealing ring; 154, connecting seat; 2, silo; 21, first rubber cavity; 22, feed channel; 23, discharge channel; 24, plugging port; 3, stop valve assembly; 31, second drive member; 311, first drive unit; 3111, first cylinder; 3112, first valve core; 3113, first wave spring; 3114, first air Dynamic cavity; 312, first valve stem; 32, first valve seat; 321, second glue cavity; 322, glue inlet; 33, first heating device; 4, glue gun assembly; 41, third driving member; 411, second driving unit; 4111, second cylinder; 4112, second valve core; 4113, second wave spring; 4114, second pneumatic cavity; 412, second valve stem; 42, second valve seat; 43, glue inlet seat; 44, heating tube; 45, glue spray head; 46, second heating device; 5, control assembly; 51, pneumatic control unit; 6, fixing seat; 61, installation cavity; 7, pressure sensor; 8, reducer. DETAILED DESCRIPTION

[0022] The following is a further detailed description of the specific implementation of the present invention in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0023] like Figure 1 and Figure 2As shown, the utility model provides a quantitative pump, including a driving component 1, a silo 2, a stop valve component 3, a glue gun component 4 and a control component 5. The driving component 1 includes a first driving member 11, a planetary ball screw 12, a planetary nut 13, a guide structure 14 and a piston rod structure 15. The silo 2 includes a first glue chamber 21, a feed channel 22 and a discharge channel 23. The first glue chamber 21 is used to store and transmit glue. The feed channel 22 is connected with the discharge channel 23 through the first glue chamber 21. The feed channel 22 and the discharge channel 23 are respectively responsible for introducing external glue into the first glue chamber 21 and delivering the glue in the first glue chamber 21 to the use point; the output shaft of the first driving member 11 is connected to the planetary ball screw 12, the planetary nut 13 is sleeved on the circumference of the planetary ball screw 12, and the planetary nut 13 is connected to the guide structure 14. The piston rod structure 15 is The end sleeve is arranged on the end of the planetary ball screw 12 away from the first driving member 11, and is connected to the planetary nut 13. The other end of the piston rod structure 15 is located in the first glue chamber 21, so as to drive the piston rod structure 15 to reciprocate in the first glue chamber 21 through the first driving member 11. The stop valve assembly 3 and the glue gun assembly 4 are installed on the silo 2, and the stop valve assembly 3 is connected with the feed channel 22, which plays a role in controlling the glue to enter the first glue chamber 21, ensuring that the feed is opened or closed at the appropriate time to prevent the glue from overflowing or backflowing when not needed. The glue gun assembly 4 is connected with the discharge channel 23, which is used to finally apply the quantitative glue to the target workpiece continuously or intermittently according to the set program or requirements. The control assembly 5 is connected with the stop valve assembly 3 and the glue gun assembly 4 to realize the precise control of the glue flow, glue discharge time and glue discharge amount to meet the strict requirements in the production process.

[0024] Based on the above structure, the first driving member 11 of this embodiment is connected to the planetary ball screw 12 through the output shaft to convert the rotational motion of the first driving member 11 into linear reciprocating motion, and when the first driving member 11 drives the planetary ball screw 12 to rotate, the planetary screw nut 13 can move along the axial direction of the planetary ball screw 12, and the guide structure 14 ensures that its linear motion trajectory is stable. With the movement of the planetary screw nut 13, the piston rod structure 15 will reciprocate in the first glue cavity 21, thereby completing the process of sucking and pushing glue. This embodiment achieves precise control of the glue flow rate through the above process, solves the problem of unstable spraying of manual handheld glue guns, and ensures that the glue coating task can be completed automatically and efficiently in the glue coating process through precise mechanical transmission, thereby improving product quality and production efficiency.

[0025] Furthermore, it also includes a fixed seat 6 with a mounting cavity 61, the guide structure 14 includes a nut seat 141 and a plurality of connecting rods 142, the first driving member 11 is connected to the fixed seat 6, the planetary ball screw 12 passes through the fixed seat 6 and extends into the mounting cavity 61, and the plurality of connecting rods 142 are installed in the mounting cavity 61 at intervals around the axis of the planetary ball screw 12 to form a support structure similar to a guide rail, the nut seat 141 is movably connected to the connecting rod 142, and can slide smoothly along the connecting rod 142 with the rotation of the planetary ball screw 12, and the planetary nut 13 is installed on the nut seat 141, when the first driving member 11 drives the planetary ball screw 12 to rotate through the fixed seat 6, the planetary nut 13 will make precise linear reciprocating motion along the axis of the planetary ball screw 12 under the guidance of the connecting rod 142, and at the same time, through the linkage with the piston rod structure 15, the precise extrusion and delivery of the glue is realized. The first driving member 11 of this embodiment is a servo motor.

[0026] Get involved Figure 3 The piston rod structure 15 includes a piston rod 151, a sealing gland 152, a sealing ring 153 and a connecting seat 154. The connecting seat 154 is used as a connecting component between the planetary nut 13 and the piston rod 151, and is used to transmit the linear motion of the planetary nut 13 to the piston rod 151 to ensure accurate transmission and response of power. That is, the connecting seat 154 is connected to the planetary nut 13, one end of the piston rod 151 is connected to the connecting seat 154 to receive the linear motion driving force from the planetary nut 13, and the other end of the piston rod 151 is connected to the sealing gland 152. The sealing cover 152 is closely matched with the piston rod 151, and is used to close the gap between the piston rod 151 and the first glue chamber 21 to prevent glue from leaking from between the piston rod 151 and the first glue chamber 21. At the same time, it also protects the piston rod 151 from being eroded by glue and maintains good sealing performance. The sealing ring 153 is sleeved on one end of the piston rod 151 close to the sealing cover 152, and is used for sealing elements. It can continuously maintain an effective sealing effect during the reciprocating motion of the piston rod 151, preventing glue leakage while reducing the wear between the piston rod 151 and the first glue chamber 21.

[0027] It should be noted that the sealing gland 152 is made of a nitrided high-quality alloy steel cylinder sleeve, and the sealing ring 153 is made of a double-layer UPE material, which makes it wear-resistant and can work normally for high-viscosity fluids and corrosive fluids.

[0028] Read also Figure 4The silo 2 also includes a blocking port 24, which cooperates with the stop valve assembly 3 to play a switch role in controlling the glue to flow into the first glue chamber 21. When the blocking port 24 is closed, the glue can be prevented from flowing from the silo 2 to the glue gun assembly 4. Specifically, the stop valve assembly 3 includes a second driving member 31, a first valve seat 32 and a first heating device 33. The second driving member 31 and the first heating device 33 are installed on the first valve seat 32. The first valve seat 32 has a second glue cavity 3221 and a glue inlet 322 connected to the second glue cavity 3221. The glue inlet 322 is used for allowing glue to enter the second glue cavity 3221 from the silo 2 and then enter the first glue cavity 21 through the connecting part. The first valve seat 32 is connected to the silo 2, and the second glue cavity 3221 is connected to the first glue cavity 21, thereby ensuring the continuity of the glue flow path. The second driving member 31 includes a first driving unit 311 and a first valve stem 312. The first valve stem 312 is located in the second glue cavity 3221. The output shaft of the first driving unit 311 is connected to one end of the first valve stem 312 to drive the other end of the first valve stem 312 to approach or move away from the blocking port 24.

[0029] In this embodiment, when the first driving unit 311 is started, the first valve stem 312 can be driven to change its position. The opening and closing action of the first valve stem 312 is used to control whether the glue can enter the first glue cavity 21 through the sealing port 24, thereby achieving precise control of the flow of glue, ensuring that the stop valve is opened only when glue is needed to allow glue to flow to the glue coating system, and can be reliably closed during non-working hours or when glue coating is stopped, preventing disorderly outflow of glue, saving resources and maintaining the accuracy of the glue coating process.

[0030] In addition, the first heating device 33 can quickly and effectively transfer heat to the adhesive, ensuring that the adhesive always maintains an ideal temperature state before the shut-off valve assembly 3 is opened or during its stay; this embodiment heats the second adhesive cavity 3221 through the first heating device 33, which can ensure that the adhesive maintains appropriate fluidity and working temperature, and prevent fluidity reduction or curing blockage caused by too low temperature.

[0031] Furthermore, the first driving unit 311 includes a first cylinder body 3111, a first valve core 3112, a first wave spring 3113 and a first connecting end. The first valve core 3112 is movably arranged in the first cylinder body 3111 to form a first pneumatic chamber 3114 with the first cylinder body 3111. One end of the first valve stem 312 passes through the first cylinder body 3111 and is connected to the first valve core 3112. The first valve core 3112 can move in the first cylinder body 3111. The position of the first valve stem 312 is adjusted by controlling the position of the first valve core 3112, thereby controlling the circulation of glue. The first wave spring 3113 is arranged in the first pneumatic chamber 3114, and the first wave spring 3113 is arranged in the first pneumatic chamber 3114. The two ends of 113 are respectively in contact with the inner wall of the first cylinder body 3111 and the outer wall of the first valve core 3112 to provide a restoring force to ensure that the first valve core 3112 can return to the initial position when there is no external drive. It can also compensate for the gap caused by factors such as wear and maintain the sealing performance and movement stability of the first valve core 3112. The first connecting end is installed on the first cylinder body 3111 and is connected to the first pneumatic chamber 3114 for receiving an external air source to control the air pressure in the pneumatic chamber through the first connecting end, and act on the first valve core 3112 to make it move in the first cylinder body 3111, thereby driving the first valve stem 312 to control the opening and closing of the stop valve assembly 3.

[0032] Furthermore, it also includes a pressure sensor 7 for detecting the pressure of the first glue chamber 21. The pressure sensor 7 is installed on the silo 2. The pressure sensor 7 is a device for real-time monitoring and measuring liquid pressure to ensure that the pressure of the glue during transportation is within a safe and stable range.

[0033] Read also Figure 5The glue gun assembly 4 includes a third driving member 41, a second valve seat 42, a glue feed seat 43, a heating pipe 44, a glue spray head 45 and a second heating device 46. The glue feed seat 43 is installed on the silo 2. The second valve seat 42 is connected to the side of the glue feed seat 43 away from the silo 2. The glue feed seat 43 receives the heated glue from the silo 2 and guides it to the inside of the second valve seat 42 to prepare for the next glue spraying operation. The heating pipe 44, the third driving member 41 and the second heating device 46 are installed on the second valve seat 42. The heating pipe 44 is used to further heat and insulate the glue to be sprayed from the glue spray head 45 to ensure that the glue still maintains a suitable temperature during spraying, is easy to flow and has good bonding properties. The glue spray head 45 is installed on The end of the heating tube 44 facing away from the second valve seat 42 is used to spray the controlled hot melt adhesive in a desired form and rate; the third driving member 41 includes a second driving unit 411 and a second valve stem 412, one end of the second valve stem 412 is connected to the output shaft of the second driving unit 411, and the other end passes through the second valve seat 42 and the heating tube 44 in turn, so as to seal or open the glue spray head 45 through the drive of the third driving member 41, wherein the second valve seat 42 is used to carry and position the heating tube 44 and the third driving member 41, and cooperate with the second valve stem 412 to control the circulation of glue. When the second valve core 4112 moves, it can open or close the channel leading to the glue spray head 45, thereby controlling whether the glue can pass through and be sprayed out.

[0034] In addition, the second heating device 46 ensures that the colloid maintains a suitable temperature before injection or in the area of ​​the second valve seat 42 so as to always maintain a molten state and prevent the colloid from cooling and solidifying to block the pipeline or affect the injection effect.

[0035] Furthermore, the second driving unit 411 includes a second cylinder body 4111, a second valve core 4112, a second wave spring 4113 and a second connecting end. The second valve core 4112 is movably arranged in the second cylinder body 4111 to form a second pneumatic chamber 4115 with the second cylinder body 4111. One end of the second valve stem 412 passes through the second cylinder body 4111 and is connected to the second valve core 4112. The second valve core 4112 can move in the first cylinder body 3111. The position of the second valve stem 412 is adjusted by controlling the position of the second valve core 4112, thereby controlling the circulation of the glue. The second wave spring 4113 is arranged in the second pneumatic chamber 4115, and the second wave spring 4113 is arranged in the second pneumatic chamber 4115. The two ends of 113 are respectively in contact with the inner wall of the second cylinder body 4111 and the outer wall of the second valve core 4112 to provide a restoring force to ensure that the second valve core 4112 can return to the initial position when there is no external drive. It can also compensate for the gap caused by wear and other factors to maintain the sealing performance and movement stability of the second valve core 4112. The second connecting end is installed on the second cylinder body 4111 and is connected to the second pneumatic chamber 4115 for receiving an external air source to control the air pressure in the pneumatic chamber through the second connecting end, and act on the second valve core 4112 to make it move in the second cylinder body 4111, thereby driving the second valve stem 412 to control the opening and closing of the stop valve assembly 3.

[0036] Furthermore, the control assembly 5 includes an air control unit 51, which is connected to the stop valve assembly 3 and the glue gun assembly 4. This embodiment adopts pneumatic control technology, and uses compressed air as a power source to control the opening and closing of the first drive unit 311, thereby realizing the opening and closing control of the flow of glue, and ensuring the accuracy of quantitative supply and stop supply of glue. Similarly, the air control unit 51 is also connected to the glue gun assembly 4, and can control the action of the second drive unit 411 according to pre-set parameters or real-time detected pressure, temperature and other signals, thereby adjusting the position of the second valve core 4112, controlling the opening and closing of the glue spray head 45 and the amount of glue sprayed.

[0037] Furthermore, it also includes a reducer 8, through which the first drive member 11 and the planetary ball screw 12 are connected. The high-speed rotation of the first drive member 11 is reduced and converted into the lower rotation speed required by the planetary ball screw 12 to meet the requirements of glue delivery speed and accuracy in the gluing process.

[0038] In summary, the embodiment of the utility model provides a quantitative pump, which has a perfect combination of servo motor and planetary roller screw precision transmission. Each precise glue discharge can be accurate to an error of about 0.05 grams, and the pneumatic control of opening and closing the glue discharge valve has a response speed of 0.3 seconds. The above is to ensure the stability of glue discharge, realize the precise control of glue flow, solve the problem of unstable spraying of manual hand-held glue guns, and through precise mechanical transmission, ensure that the glue coating process can be completed automatically and efficiently, improve product quality and production efficiency. In addition, the large torque of the planetary roller screw can make the pressure reach up to 40Mpa, which is suitable for various occasions of flat, side and back glue coating, while stably and continuously maintaining the quality and work efficiency of glue coating.

[0039] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principle of the present invention. These improvements and substitutions should also be regarded as the protection scope of the present invention.

Claims

1. A metering pump, characterized in that: It includes a driving component, a silo, a stop valve component, a glue gun component and a control component. The driving component includes a first driving member, a planetary ball screw, a planetary nut, a guide structure and a piston rod structure. The silo includes a first glue chamber, a feed channel and a discharge channel. The feed channel is connected with the discharge channel through the first glue chamber. The output shaft of the first driving member is connected with the planetary ball screw. The planetary nut is sleeved on the circumference of the planetary ball screw, and the planetary nut is connected with the guide structure. One end of the piston rod structure is sleeved on the end of the planetary ball screw away from the first driving member and is connected with the planetary nut. The other end of the piston rod structure is located in the first glue chamber, so as to drive the piston rod structure to reciprocate in the first glue chamber through the first driving member. The stop valve component and the glue gun component are installed on the silo, and the stop valve component is connected with the feed channel, and the glue gun component is connected with the discharge channel. The control component is connected with the stop valve component and the glue gun component.

2. The metering pump according to claim 1, characterized in that: It also includes a fixed seat with an installation cavity, the guide structure includes a nut seat and a plurality of connecting rods, the first driving member is connected to the fixed seat, the planetary ball screw passes through the fixed seat and extends into the installation cavity, a plurality of connecting rods are installed in the installation cavity at intervals around the axis of the planetary ball screw, the nut seat is movably connected to the connecting rod, and the planetary nut is installed on the nut seat.

3. The metering pump according to claim 1, characterized in that: The piston rod structure includes a piston rod, a sealing cover, a sealing ring and a connecting seat. The connecting seat is connected to the planetary nut, one end of the piston rod is connected to the connecting seat, and the other end of the piston rod is connected to the sealing cover. The sealing ring is sleeved on one end of the piston rod close to the sealing cover.

4. The metering pump according to claim 1, characterized in that: The silo also includes a sealing port, the stop valve assembly includes a second drive member, a first valve seat and a first heating device, the second drive member and the first heating device are installed on the first valve seat, the first valve seat has a second glue cavity and a glue inlet communicated with the second glue cavity, the first valve seat is connected to the silo, and the second glue cavity is communicated with the first glue cavity, the second drive member includes a first drive unit and a first valve stem, the first valve stem is located in the second glue cavity, and the output shaft of the first drive unit is connected to one end of the first valve stem to drive the other end of the first valve stem to approach or move away from the sealing port.

5. The metering pump according to claim 4, characterized in that: The first driving unit also includes a first cylinder body, a first valve core, a first wave spring and a first connecting end. The first valve core is movably arranged in the first cylinder body to form a first pneumatic chamber with the first cylinder body. One end of the first valve stem passes through the first cylinder body and is connected to the first valve core. The first wave spring is arranged in the first pneumatic chamber, and the two ends of the first wave spring are respectively abutted against the inner wall of the first cylinder body and the outer wall of the first valve core. The first connecting end is installed on the first cylinder body and is connected to the first pneumatic chamber.

6. The metering pump according to claim 1, characterized in that: It also includes a pressure sensor for detecting the pressure of the first glue cavity, and the pressure sensor is installed on the silo.

7. The metering pump according to claim 1, characterized in that: The glue gun assembly includes a third driving member, a second valve seat, a glue feed seat, a heating tube, a glue spray head and a second heating device. The glue feed seat is installed on the silo. The second valve seat is connected to the side of the glue feed seat away from the silo. The heating tube, the third driving member and the second heating device are installed on the second valve seat. The glue spray head is installed at one end of the heating tube away from the second valve seat. The third driving member includes a second driving unit and a second valve stem. One end of the second valve stem is connected to the output shaft of the second driving unit, and the other end passes through the second valve seat and the heating tube in sequence to seal or open the glue spray head through the drive of the third driving member.

8. The metering pump according to claim 7, characterized in that: The second driving unit also includes a second cylinder body, a second valve core, a second wave spring and a second connecting end. The second valve core is movably arranged in the second cylinder body to form a second pneumatic chamber with the second cylinder body. One end of the second valve stem passes through the second cylinder body and is connected to the second valve core. The second wave spring is arranged in the second pneumatic chamber, and the two ends of the second wave spring are respectively abutted against the inner wall of the second cylinder body and the outer wall of the second valve core. The second connecting end is installed on the second cylinder body and is connected to the second pneumatic chamber.

9. The metering pump according to claim 1, characterized in that: The control assembly includes an air control unit, and the air control unit is connected to the stop valve assembly and the glue gun assembly.

10. The metering pump according to claim 1, characterized in that: It also includes a reducer, and the first driving member and the planetary ball screw are connected through the reducer.

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