Double back suction dispensing valve

Abstract

The utility model proposes a double back-suction type glue dispensing valve, including a valve body, a connector, a glue dispensing nozzle and a valve stem, wherein the connector is fixed at the bottom of the valve body, and the glue dispensing nozzle is detachably connected at the bottom of the connector; the middle of the valve body includes an air control chamber, a sealing chamber, a material chamber and a glue sealing port I in sequence from the upper end face to the lower end face; the middle of the connector includes a back-suction chamber I and a glue sealing port II in sequence from the upper end face to the lower end face; the middle of the glue dispensing nozzle includes a back-suction chamber II and a glue outlet channel in sequence from the upper end face to the lower end face; the valve stem extends downward from the air control chamber into the back-suction chamber II, and a glue sealing device I for cooperating with the glue sealing port I and a glue sealing device II for cooperating with the glue sealing port II are fixed at the lower part of the valve stem, and the volume of the back-suction chamber II is smaller than that of the back-suction chamber I. When the utility model is closed, the valve stem moves upward, so that the internal pressure of the valve body drops instantaneously, and there is an instantaneous back-suction effect, which avoids the problem of large lumps of glue when the valve body is collecting glue after glue application.

Description

Technical Field

[0001] The utility model relates to the field of glue dispensing valves, in particular to a double-return suction type glue dispensing valve. Background Art

[0002] The dispensing system is a process equipment widely used in the field of product production. Its scope of use covers the bonding, potting, coating, sealing, filling, padding, marking and gluing of products. Among them, the dispensing valve is the core component of the dispensing system. The current market generally uses needle dispensing valves. Because the viscosity and consistency of the glue used in different dispensing scenarios are different, some glues will have a large lump of glue at the outlet after dispensing due to glue residue and gravity, which is not suitable for some scenes with high dispensing quality requirements. Therefore, it is necessary to design a new dispensing valve glue to solve the above problems. Utility Model Content

[0003] The utility model provides a double-return suction type glue dispensing valve, which solves the problem that a large lump of glue exists when the existing glue dispensing valve dispensing ends.

[0004] The technical solution of the utility model is achieved in this way:

[0005] A double back-suction dispensing valve comprises a valve body, a connecting head, a dispensing nozzle and a valve stem, wherein the connecting head is fixed at the bottom of the valve body, and the dispensing nozzle is detachably connected to the bottom of the connecting head; the middle of the valve body comprises an air control chamber, a sealing chamber, a material chamber and a sealing port I in sequence from the upper end face to the lower end face; the middle of the connecting head comprises a back-suction chamber I and a sealing port II in sequence from the upper end face to the lower end face; the middle of the dispensing nozzle comprises a back-suction chamber II and a glue outlet channel in sequence from the upper end face to the lower end face; the valve stem extends downward from the air control chamber into the back-suction chamber II, and the sealing port I and the sealing port II are both conical ports that are small at the top and large at the bottom, and a sealing device I for cooperating with the sealing port I and a sealing device II for cooperating with the sealing port II are fixed at the lower part of the valve stem, and the volume of the back-suction chamber II is smaller than that of the back-suction chamber I.

[0006] Furthermore, the sealing device I is a conical head I or a sealing ring I, and the sealing device II is a conical head II or a sealing ring II.

[0007] Furthermore, the conical head I is sleeved on the lower part of the valve stem, and the valve stem is provided with a limiting step for limiting the position of the upper end surface of the conical head I. The valve stem is also provided with a fixing nut for cooperating with the limiting step to clamp the conical head I, and the fixing nut is threadedly connected to the valve stem. A sealing ring III is provided between the conical head I and the limiting step, and a sealing ring IV is provided on the outer cone surface of the conical head I.

[0008] Furthermore, a sealing bushing is fixed in the sealing cavity, at least two sealing rings V are arranged on the outer circumferential side of the sealing bushing, a bushing chamber leading to the lower end face is opened in the middle of the upper end face of the sealing bushing, the bushing chamber comprises an upper sealing cavity, a rod hole and a lower sealing cavity from top to bottom, the diameter of the rod hole is smaller than that of the upper sealing cavity and the lower sealing cavity, a sealing pressure ring is fixed in the upper sealing cavity, at least one sealing ring VI is arranged between the outer circumferential side of the sealing pressure ring and the side wall of the upper sealing cavity, a sealing ring VII is arranged between the lower end face of the sealing pressure ring and the lower end face of the upper sealing cavity, a sealing ring IX is fixed in the lower sealing cavity, and the sealing pressure ring is fixed in the upper sealing cavity by a retaining ring through the hole.

[0009] Furthermore, a circle of fixing grooves is provided in the middle of the outer side wall of the sealing bushing, and fixing screw holes leading to the sealing cavity are provided on the outer side wall opposite to the valve body, and set screws extending to the fixing grooves are provided in the fixing screw holes.

[0010] Furthermore, a piston is fixedly connected to the upper end of the valve stem, a cylinder piston seal is arranged on the outer circumferential surface of the piston, a spring is arranged between the piston and the sealing bushing, and the spring is sleeved outside the valve stem.

[0011] Furthermore, a spring positioning groove is provided on the lower end surface of the piston and the upper end surface of the sealing bushing; a valve stem screw hole is provided at the center of the lower end surface of the piston, and the upper end of the valve stem is a connecting screw that cooperates with the valve stem screw hole.

[0012] Furthermore, the upper end surface of the valve body is also fixedly connected to a valve cover, and the middle of the valve cover includes an adjusting screw hole and a sliding hole in sequence from the upper end surface to the lower end surface, an adjusting bolt is arranged in the adjusting screw hole, and an anti-loosening nut is arranged outside the adjusting bolt, and the anti-loosening nut is located on the upper end surface of the valve cover, and a sliding column is fixedly connected to the middle of the upper end of the piston, and the upper end of the sliding column is rotatably connected to the adjusting bolt, and a sealing ring VIII is arranged on the outer side wall of the sliding column.

[0013] Furthermore, a radial T-shaped groove is formed on the lower outer side surface of the adjusting bolt, and a T-shaped rod matching the T-shaped groove is fixedly connected to the upper end of the sliding column.

[0014] Furthermore, an upper air hole and a lower air hole leading to the air control chamber are provided on the outer surface of the valve body, and the upper air hole and the lower air hole are respectively located above and below the piston; a feed hole leading to the material chamber is provided on the outer surface of the valve body; the valve cover is fixedly connected to the valve body by a plurality of first screws, the connecting head is fixedly connected to the valve body by a plurality of second screws, and the dispensing nozzle is connected to the connecting head by a nozzle fixing nut; a first sealing ring is provided between the valve cover and the valve body, a second sealing ring is provided between the valve body and the connecting head, and a third sealing ring is provided between the connecting head and the dispensing nozzle.

[0015] Beneficial effects of the utility model:

[0016] 1. When the traditional needle dispensing valve is closed, the valve stem moves downward, while when the utility model is closed, the valve stem moves upward, so that the internal pressure of the valve body drops instantly, and there is an instantaneous back-sucking effect, which avoids the problem of large lumps of glue appearing in the valve body when the glue is collected after the glue application is completed.

[0017] 2. The utility model adopts a double back-suction structure of a glue sealing device I, a glue sealing device II, a back-suction chamber I and a back-suction chamber II, and the back-suction effect is better. The back-suction chamber I and the back-suction chamber II are separated by the glue sealing device II, and the back-suction chamber II is smaller than the back-suction chamber I, which avoids the colloid in the glue outlet channel being squeezed out of the glue dispensing nozzle under the action of the colloid's own weight due to the large spatial volume of the back-suction chamber I after back-suction, and most of the residual glue after back-suction is locked in the back-suction chamber I. This structure has a better glue locking performance for the valve body after the glue application is completed.

[0018] 3. The sealing bushing in the valve body adopts a multiple sealing structure to prevent the medium from flowing between the air control chamber and the material chamber, and increase the service life.

[0019] 4. The utility model discloses a novel adjusting bolt connected with the valve cover by threading. When the glue output is to be adjusted, the adjusting bolt is screwed in and out for adjustment, and then the anti-loosening nut is used to lock and prevent loosening. The adjustment is convenient and the precision is high. After the anti-loosening nut is locked, the position is not easy to change. There is no need to use two anti-loosening nuts as in the traditional method, which makes the adjustment complicated and the precision is low. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 It is a three-dimensional diagram of the utility model;

[0022] Figure 2 It is the front view of the utility model;

[0023] Figure 3 for Figure 2 Section view along line AA;

[0024] Figure 4 It is a three-dimensional diagram of the adjusting bolt in the utility model;

[0025] Figure 5 It is a cross-sectional view of the valve cover in the utility model;

[0026] Figure 6It is a three-dimensional diagram of the piston and the valve stem in the utility model;

[0027] Figure 7 It is a cross-sectional view of the piston and the valve stem in the utility model;

[0028] Figure 8 It is a cross-sectional view of the valve body in the utility model;

[0029] Fig. 9 It is a cross-sectional view of the sealing bushing in the utility model;

[0030] Fig.10 It is a cross-sectional view of the connector in the utility model;

[0031] Fig.11 It is a cross-sectional view of the glue dispensing nozzle in the utility model.

[0032] In the figure: 1-valve cover, 11-first screw, 12-adjusting screw hole, 13-sliding hole, 14-first sealing ring, 2-valve body, 20-second sealing ring, 21-upper air hole, 22-lower air hole, 23-feeding hole, 24-air control chamber, 25-sealing chamber, 26-material chamber, 27-sealing port I, 28-fixing screw hole, 29-setting screw, 3-connector, 31-second screw, 32-glue nozzle fixing nut, 33-return suction chamber I, 34-sealing port II, 35-third sealing ring, 4-glue nozzle, 41-return suction chamber II, 42-glue outlet channel, 5-adjusting bolt, 51-locking nut, 52-T-slot, 6- Piston, 61-cylinder piston seal, 62-sliding column, 63-sealing ring VIII, 64-T-rod, 65-valve stem screw hole, 7-spring, 8-sealing bushing, 81-sealing ring V, 82-upper sealing chamber, 83-rod hole, 84-lower sealing chamber, 85-sealing pressure ring, 851-sealing ring VI, 852-sealing ring VII, 86-sealing ring IX, 87-hole retaining ring, 88-fixing groove, 89-spring positioning groove, 891-support gasket, 9-valve stem, 91-conical head I, 92-sealing ring II, 93-limiting step, 94-sealing ring IV, 95-sealing ring III, 96-fixing nut. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0034] Reference Figure 1-11, a double back-suction dispensing valve, comprising a valve body 2, a connecting head 3, a dispensing nozzle 4 and a valve stem 9, wherein the connecting head 3 is fixed at the bottom of the valve body 2, and the dispensing nozzle 4 is detachably connected to the bottom of the connecting head 3; the middle of the valve body 2 includes an air control chamber 24, a sealing chamber 25, a material chamber 26 and a sealing port I27 from the upper end face to the lower end face; the middle of the connecting head includes a back-suction chamber I33 and a sealing port II34 from the upper end face to the lower end face; the middle of the dispensing nozzle 4 includes a back-suction chamber II41 and a glue outlet channel 42 from the upper end face to the lower end face; the valve stem 9 extends downward from the air control chamber into the back-suction chamber II41, and the sealing port I27 and the sealing port II34 are both conical ports with a small upper part and a large lower part, and a sealing device I for cooperating with the sealing port I27 and a sealing device II for cooperating with the sealing port II34 are fixed at the lower part of the valve stem 9, and the volume of the back-suction chamber II41 is smaller than that of the back-suction chamber I33.

[0035] When the traditional needle dispensing valve is closed, the valve stem moves downward, while when the utility model is closed, the valve stem 9 moves upward, which has a suck-back effect, thereby avoiding the problem of large lumps of glue when collecting glue after the glue application is completed.

[0036] The utility model adopts a double back-suction structure of a glue sealing device I, a glue sealing device II, a back-suction chamber I33 and a back-suction chamber II41, and the back-suction effect is better. The back-suction chamber I33 and the back-suction chamber II41 are separated by the glue sealing device II, and the back-suction chamber II41 is smaller than the back-suction chamber I33, which avoids the colloid in the glue outlet channel 42 being squeezed out of the glue dispensing nozzle 4 under the action of the colloid's own weight due to the large spatial volume of the back-suction chamber I33 after back-suction, and most of the residual glue after back-suction is locked in the back-suction chamber I33. This structure has better glue locking performance after the glue application is completed.

[0037] Among them, the sealing device I is a conical head I91 or a sealing ring I, and the sealing device II is a conical head II or a sealing ring II92.

[0038] When the sealing device I is a conical head I91, the conical head I is sleeved on the lower part of the valve stem 9, and the valve stem 9 is provided with a limiting step 93 for limiting the position of the upper end surface of the conical head I91. The valve stem 9 is also provided with a fixing nut 96 for cooperating with the limiting step to clamp the conical head I. The fixing nut 96 is threadedly connected to the valve stem 9, and a sealing ring III95 is provided between the conical head I91 and the limiting step 93, and a sealing ring IV94 is provided on the outer cone surface of the conical head I91.

[0039] As a further implementation scheme, a sealing bushing 8 is fixed in the sealing cavity 25, and at least two sealing rings V81 are arranged on the outer circumferential side of the sealing bushing 8. A bushing chamber to the lower end face is opened in the middle of the upper end face of the sealing bushing 8. The bushing chamber includes an upper sealing cavity 82, a rod hole 83 and a lower sealing cavity 84 from top to bottom. The diameter of the rod hole 83 is smaller than that of the upper sealing cavity 82 and the lower sealing cavity 84. A sealing pressure ring 85 is fixed in the upper sealing cavity 82. At least one sealing ring VI851 is arranged between the outer circumferential side of the sealing pressure ring 85 and the side wall of the upper sealing cavity. A sealing ring VII852 is arranged between the lower end face of the sealing pressure ring 85 and the lower end face of the upper sealing cavity 82. A sealing ring IX86 is fixed in the lower sealing cavity 84, and the sealing pressure ring 85 is fixed in the upper sealing cavity 82 by a retaining ring 87 through a hole. The sealing ring IX86 can be selected as a pneumatic tie rod seal or an O-ring.

[0040] A fixing groove 88 is formed in the middle of the outer wall of the sealing bushing 8 , and a fixing screw hole 28 leading to the sealing cavity is formed on the opposite outer wall of the valve body 2 . A set screw 29 extending to the fixing groove 88 is arranged in the fixing screw hole 28 .

[0041] The sealing bushing 8 in the valve body 2 adopts a multiple sealing structure to prevent the medium from flowing between the air control chamber 24 and the material chamber 26 and to increase the service life.

[0042] As a further implementation scheme, the upper end of the valve stem 9 is fixedly connected to a piston 6 , the outer circumferential surface of the piston 6 is provided with a cylinder piston seal 61 , a spring 7 is provided between the piston 6 and the sealing bushing 8 , and the spring 7 is sleeved outside the valve stem 9 .

[0043] Among them, the lower end surface of the piston 6 and the upper end surface of the sealing bushing are both provided with a spring positioning groove 89; a supporting gasket 891 can be placed in the spring positioning groove 89 on the upper end surface of the sealing bushing to support the spring 7, and a valve stem screw hole 65 is provided in the center of the lower end surface of the piston 6, and the upper end of the valve stem 9 is a connecting screw that cooperates with the valve stem screw hole.

[0044] As a further implementation scheme, the upper end surface of the valve body 2 is also fixedly connected to the valve cover 1, and the middle of the valve cover 1 includes an adjusting screw hole 12 and a sliding hole 13 from the upper end surface to the lower end surface in sequence. An adjusting bolt 5 is arranged in the adjusting screw hole 12, and the adjusting bolt 5 can select a hexagon socket bolt. A locking nut 51 is arranged outside the adjusting bolt 5, and the locking nut 51 is located on the upper end surface of the valve cover 1. A sliding column 62 is fixedly connected to the middle of the upper end of the piston 6, and the upper end of the sliding column 62 is rotatably connected to the adjusting bolt 5, and a sealing ring VIII63 is arranged on the outer wall of the sliding column 62.

[0045] A radial T-shaped slot 52 is formed on the lower outer side surface of the adjusting bolt 5 , and a T-shaped rod 64 matching the T-shaped slot 52 is fixedly connected to the upper end of the sliding column 62 .

[0046] The traditional way of adjusting the valve core stroke of the back-suction valve adopts a double-nut structure. The empty sleeve of the adjusting valve core passes through the air control end cover, and the double nuts are fixed on the adjusting valve core. The adjusting nut plays the role of adjusting the stroke, and the anti-loosening nut plays the role of preventing the adjusting nut from changing its position. During the adjustment process, the relative positions of the adjusting valve core, the adjusting nut and the anti-loosening nut must be taken into account. First, it is difficult to operate. Second, when the anti-loosening nut is finally locked, the adjusted stroke often changes slightly. For working conditions with small glue volume and high glue adjustment accuracy, it is difficult to adjust to the desired glue volume position. The new adjusting bolt of the utility model is threadedly connected with the valve cover. When the glue output volume is to be adjusted, it is adjusted by screwing the adjusting bolt in and out, and then locked and prevented by the anti-loosening nut. The adjustment is convenient and accurate. After the anti-loosening nut is locked, the position is not easy to change. There is no need to use two anti-loosening nuts like the traditional method, and the adjustment is complicated and has low accuracy.

[0047] As a further implementation scheme, an upper air hole 21 and a lower air hole 22 leading to the air control chamber are provided on the outer surface of the valve body 2, and the upper air hole 21 and the lower air hole 22 are respectively located above and below the piston 6; a feed hole 23 leading to the material chamber is provided on the outer surface of the valve body 2; the valve cover 1 is fixedly connected to the valve body 2 by a plurality of first screws 11, the connecting head 3 is fixedly connected to the valve body 2 by a plurality of second screws 31, and the dispensing nozzle 4 is connected to the connecting head 3 by a nozzle fixing nut 32; a first sealing ring 14 is arranged between the valve cover 1 and the valve body 2, a second sealing ring 20 is arranged between the valve body 2 and the connecting head 3, and a third sealing ring 35 is arranged between the connecting head 3 and the dispensing nozzle 4.

[0048] Working principle: In the initial position, the piston 6 moves upward to the highest position under the action of the elastic force of the spring 7, and the piston 6 drives the valve stem 9 to move upward to the highest position. The sealing device I and the sealing device II respectively block the sealing port I27 and the sealing port II34, and the glue enters the material cavity 26 from the feed hole 23 and is blocked, so that no glue is discharged at this time; when dispensing glue, the high-pressure gas enters the air control cavity 24 from the upper air hole 21, and the lower air hole 22 discharges gas, overcoming the elastic force of the spring 7 to press the piston 6 downward, and the piston 6 drives the valve stem 9 to move downward, and the sealing device I and the sealing device II are separated. Do not separate from the sealing port I27 and the sealing port II34, the glue enters the glue outlet channel 42 from the material chamber 26, and dispensing is performed. After the dispensing is completed, high-pressure gas enters from the lower air hole 22, and the upper air hole 21 discharges gas, pushing the piston 6 upward, pushing the piston 6 upward, and the piston drives the valve stem 9 to move upward. The sealing device I and the sealing device II respectively block the sealing port I27 and the sealing port II34. After the dispensing is completed, the valve stem 9 drives the sealing device I and the sealing device II to move upward. There is a sucking effect in the process, which avoids the problem of large lumps of glue when the valve body 2 is collecting the glue after the glue application is completed.

[0049] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. Double back-suction dispensing valve, characterized by: It includes a valve body, a connector, a dispensing nozzle and a valve stem, wherein the connector is fixed at the bottom of the valve body, and the dispensing nozzle is detachably connected to the bottom of the connector; The middle of the valve body includes an air control cavity, a sealing cavity, a material cavity and a sealing port I in sequence from the upper end surface to the lower end surface; The middle of the connector includes a suction cavity I and a sealing port II from the upper end surface to the lower end surface; The middle of the dispensing nozzle includes a suction cavity II and a dispensing channel from the upper end surface to the lower end surface; The valve stem extends downward from the air control chamber into the back-suction chamber II. The sealing port I and the sealing port II are both conical ports that are small at the top and large at the bottom. A sealing device I for cooperating with the sealing port I and a sealing device II for cooperating with the sealing port II are fixed to the lower part of the valve stem. The volume of the back-suction chamber II is smaller than that of the back-suction chamber I.

2. The double back-suction dispensing valve according to claim 1, characterized in that: The sealing device I is a conical head I or a sealing ring I, and the sealing device II is a conical head II or a sealing ring II.

3. The double back-suction dispensing valve according to claim 2, characterized in that: The conical head I is sleeved on the lower part of the valve stem, and the valve stem is provided with a limiting step for limiting the position of the upper end surface of the conical head I. The valve stem is also provided with a fixing nut for cooperating with the limiting step to clamp the conical head I, and the fixing nut is threadedly connected to the valve stem. A sealing ring III is provided between the conical head I and the limiting step, and a sealing ring IV is provided on the outer cone surface of the conical head I.

4. The double back-suction dispensing valve according to any one of claims 1 to 3, characterized in that: A sealing bushing is fixed in the sealing cavity, and at least two sealing rings V are arranged on the outer circumferential side of the sealing bushing. A bushing chamber leading to the lower end face is opened in the middle of the upper end face of the sealing bushing. The bushing chamber includes an upper sealing cavity, a rod hole and a lower sealing cavity from top to bottom. The diameter of the rod hole is smaller than that of the upper sealing cavity and the lower sealing cavity. A sealing pressure ring is fixed in the upper sealing cavity, and at least one sealing ring VI is arranged between the outer circumferential side of the sealing pressure ring and the side wall of the upper sealing cavity. A sealing ring VII is arranged between the lower end face of the sealing pressure ring and the lower end face of the upper sealing cavity. A sealing ring IX is fixed in the lower sealing cavity, and the sealing pressure ring is fixed in the upper sealing cavity by a retaining ring through the hole.

5. The double back-suction dispensing valve according to claim 4, characterized in that: A circle of fixing groove is provided in the middle of the outer side wall of the sealing bushing, and a fixing screw hole leading to the sealing cavity is provided on the outer side wall opposite to the valve body, and a set screw extending to the fixing groove is arranged in the fixing screw hole.

6. The double back-suction dispensing valve according to claim 5, characterized in that: The upper end of the valve stem is fixedly connected with a piston, the outer circumferential surface of the piston is provided with a cylinder piston seal, a spring is provided between the piston and the sealing bushing, and the spring is sleeved outside the valve stem.

7. The double back-suction dispensing valve according to claim 6, characterized in that: The lower end surface of the piston and the upper end surface of the sealing bushing are both provided with spring positioning grooves; the center of the lower end surface of the piston is provided with a valve stem screw hole, and the upper end of the valve stem is a connecting screw matched with the valve stem screw hole.

8. The double back-suction dispensing valve according to claim 7, characterized in that: The upper end surface of the valve body is also fixedly connected to a valve cover, and the middle of the valve cover includes an adjusting screw hole and a sliding hole in sequence from the upper end surface to the lower end surface, an adjusting bolt is arranged in the adjusting screw hole, and an anti-loosening nut is arranged outside the adjusting bolt, and the anti-loosening nut is located on the upper end surface of the valve cover, and a sliding column is fixedly connected to the middle of the upper end of the piston, and the upper end of the sliding column is rotatably connected to the adjusting bolt, and a sealing ring VIII is arranged on the outer side wall of the sliding column.

9. The double back-suction dispensing valve according to claim 8, characterized in that: A radial T-shaped groove is formed on the outer side surface of the lower part of the adjusting bolt, and a T-shaped rod matched with the T-shaped groove is fixedly connected to the upper end of the sliding column.

10. The double back-suction dispensing valve according to claim 9, characterized in that: An upper air hole and a lower air hole leading to the air control chamber are provided on the outer surface of the valve body, and the upper air hole and the lower air hole are respectively located above and below the piston; a feed hole leading to the material chamber is provided on the outer surface of the valve body; the valve cover is fixedly connected to the valve body by a plurality of first screws, the connecting head is fixedly connected to the valve body by a plurality of second screws, and the dispensing nozzle is connected to the connecting head by a nozzle fixing nut; a first sealing ring is provided between the valve cover and the valve body, a second sealing ring is provided between the valve body and the connecting head, and a third sealing ring is provided between the connecting head and the dispensing nozzle.

Images