Series type hot melt adhesive valve

Abstract

The utility model relates to a point gumming equipment technical field, specifically disclose a series connection type hot melt glue valve, include: valve body, the inside of valve body is equipped with the glue storage cavity for storing hot melt adhesive and the hot melt adhesive entrance that communicates to the glue storage cavity, glue cavity sealing assembly, glue cavity sealing assembly is fixed in the inside of valve body, is used for sealing the upper end opening of glue storage cavity, wherein, glue cavity sealing assembly includes at least two glue cavity sealing piece that sets up in turn layer by layer, the pin, the pin from top to bottom in turn slides through each glue cavity sealing piece, and then, extends into the glue storage cavity, hot melt glue supply component, the glue outlet of hot melt glue supply component communicates to the hot melt adhesive entrance, is used for conveying hot melt adhesive to the hot melt adhesive entrance, the utility model provides a series connection type hot melt glue valve, can effectively solve the problem that the existing hot melt point gumming valve is easy to leak hot melt adhesive and backfill air.

Description

Technical Field

[0001] This utility model relates to the field of dispensing equipment technology, and in particular to a series hot melt adhesive valve. Background Technology

[0002] See Figure 1 Existing hot melt adhesive valves typically employ a single-stage sealing structure to achieve adhesive circuit sealing. Specifically, the valve body 1 has an internal storage chamber 101 for storing hot melt adhesive, and the top of the storage chamber 101 is provided with a single-layer adhesive chamber seal 203 (such as nitrile rubber) to seal the storage chamber 101.

[0003] The upper end of the impact pin 3 extends to the actuator such as the piezoelectric membrane, and the lower end slides through the single-layer glue cavity seal 203 and extends to the top of the nozzle 5. After the silicone enters the glue storage cavity 101 from the hot melt glue inlet 102 under the action of air pressure, the actuator drives the impact pin 3 to reciprocate and strike the nozzle 5, so that the hot melt glue in the glue storage cavity 101 can be sprayed out through the nozzle 5, thereby realizing the glue dispensing operation.

[0004] Existing hot melt dispensing valves have the following technical defects:

[0005] The high-speed reciprocating motion of the impact pin 3 easily leads to wear of the single-layer rubber cavity seal 203. After wear, the single-layer rubber cavity seal 203 will:

[0006] On the one hand, hot melt adhesive is prone to leaking upwards through the gap between the single-layer adhesive cavity seal 203 and the ejector pin 3, eventually overflowing and polluting the workshop environment;

[0007] On the other hand, outside air can easily enter the glue storage chamber 101 through the gap between the single-layer glue cavity seal 203 and the ejector pin 3. After contacting the hot melt glue, the hot melt glue will solidify, eventually causing the nozzle 5 to become clogged and the dispensing accuracy to decrease.

[0008] Therefore, existing hot melt dispensing valves need to be improved to solve the problems of easy hot melt adhesive leakage and backflow of air.

[0009] The information disclosed in this background section is included only to enhance the understanding of the context of this disclosure, and therefore may contain information that does not constitute prior art known to those skilled in the art. Utility Model Content

[0010] One objective of this invention is to provide a series hot melt adhesive valve that can effectively solve the problems of hot melt adhesive leakage and air backflow in existing hot melt dispensing valves.

[0011] To achieve the above objectives, this utility model provides a series-connected hot melt adhesive valve, comprising:

[0012] The valve body has an internal storage chamber for storing hot melt adhesive and a hot melt adhesive inlet connected to the storage chamber.

[0013] A glue cavity sealing assembly is fixed inside the valve body and is used to seal the upper opening of the glue storage cavity; wherein, the glue cavity sealing assembly includes at least two glue cavity sealing elements arranged in sequence and stacked.

[0014] The striking pin slides from top to bottom through each of the glue cavity seals and then extends into the glue storage cavity;

[0015] A hot melt adhesive supply assembly, wherein the outlet of the hot melt adhesive supply assembly is connected to the hot melt adhesive inlet, for supplying hot melt adhesive to the hot melt adhesive inlet.

[0016] Optionally, the number of the cavity seals is two.

[0017] Optionally, the upper cavity seal includes a seal body, the seal body having a cylindrical needle hole through which the striking pin slides and seals.

[0018] The bottom surface of the sealing element body is provided with an annular groove, and an inverted V-shaped preload spring is provided in the annular groove;

[0019] The inverted V-shaped preload spring is used to drive the cylindrical hole wall through which the needle hole passes tightly against the striking pin.

[0020] Optionally, the V-shaped opening of the inverted V-shaped preload spring is provided with a preload O-ring for outward support of the inverted V-shaped preload spring.

[0021] Optionally, the lower cavity seal includes an annular outer sleeve and a conical inner sleeve fixed inside the annular outer sleeve and surrounding a conical needle hole.

[0022] The lower end of the conical inner sleeve extends into the glue storage cavity, and its diameter gradually decreases from top to bottom.

[0023] Optionally, a leak-proof cavity is provided between the annular outer sleeve and the conical inner sleeve.

[0024] Optionally, the hot melt adhesive supply assembly includes:

[0025] A glue storage cylinder, wherein the glue storage cylinder has a cavity communicating with the hot melt glue inlet;

[0026] A heating component is fixed to the glue storage cylinder and is used to heat and melt the hot melt glue in the cylinder cavity.

[0027] Optionally, the heating assembly includes:

[0028] A heat transfer sleeve is fitted over the outside of the glue storage cylinder;

[0029] An electric heating rod is fixed to the side of the heat transfer sleeve and is thermally connected to the heat transfer sleeve.

[0030] The beneficial effects of this utility model are as follows: It provides a series hot melt adhesive valve, which forms a multi-stage series sealing structure at the upper end of the adhesive storage cavity by setting at least two sequentially stacked adhesive cavity sealing elements.

[0031] Specifically, when the ejector pin reciprocates, each layer of the rubber cavity seal forms a continuous dynamic sealing interface along its axial direction, creating a stepped pressure gradient between the rubber cavity seal and the ejector pin. In this structure, if the lower rubber cavity seal near the rubber storage cavity develops gaps due to long-term friction, the upper rubber cavity seal can still maintain an effective seal. This means that the hot melt adhesive leakage path must continuously break through multiple sealing barriers, significantly extending the gap accumulation time required for leakage to occur.

[0032] Meanwhile, the reverse air infiltration path is divided into multiple isolation sections by the multi-stage sealing structure. Even if there are micro gaps in a single-stage seal, the remaining sealing layer can still maintain the airtight state inside the adhesive storage cavity, preventing the hot melt adhesive from solidifying upon contact with air.

[0033] Therefore, the series hot melt adhesive valve provided by this utility model can effectively solve the problems of hot melt adhesive leakage and air backflow in existing hot melt dispensing valves. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 A schematic diagram of the structure of an existing hot melt adhesive valve is provided for the background art.

[0036] Figure 2 A schematic diagram of the structure of the series hot melt adhesive valve provided in the embodiment;

[0037] Figure 3 A schematic diagram of the cavity sealing assembly provided in the embodiment;

[0038] Figure 4 An exploded view of the series hot melt adhesive valve provided in the embodiment.

[0039] In the picture:

[0040] 1. Valve body; 101. Glue storage chamber; 102. Hot melt glue inlet;

[0041] 2. Cavity sealing assembly;

[0042] 201. Upper cavity seal; 2011. Seal body; 2012. V-type preload spring; 2013. Preload O-ring;

[0043] 202. Lower cavity seal; 2021. Annular outer sleeve; 2022. Conical inner sleeve;

[0044] 203. Single-layer rubber cavity seal;

[0045] 3. Firing pin;

[0046] 4. Return spring;

[0047] 5. Nozzle;

[0048] 6. Threaded locking cap;

[0049] 7. Guide sleeve;

[0050] 8. Implementing agency;

[0051] 9. Hot melt adhesive supply assembly; 901. Adhesive storage cylinder; 9011. Cylinder cavity; 902. Heating assembly; 9021. Heat transfer jacket; 9022. Heating rod. Detailed Implementation

[0052] In this utility model, the reference to "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment can be included in at least one embodiment of this utility model. The term "embodiment" appearing in various places throughout the specification does not necessarily refer to the same embodiment, nor does it specifically limit its independence or connection with other embodiments. In principle, in this utility model, as long as there are no technical contradictions or conflicts, the technical features mentioned in each embodiment can be combined in any way to form corresponding implementable technical solutions.

[0053] Unless otherwise defined, the technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains; the use of related terms herein is merely for the purpose of describing particular embodiments and is not intended to limit the invention.

[0054] In the description of this utility model, the term "and / or" is used to describe the logical relationship between objects, indicating that three relationships can exist. For example, A and / or B means: A exists, B exists, and A and B exist simultaneously. Additionally, the character " / " generally indicates that the preceding and following objects have an "or" logical relationship.

[0055] In this invention, terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any actual quantity, hierarchy, or order between these entities or operations.

[0056] Without further limitations, the use of terms such as “comprising,” “including,” “having,” or other similar expressions in this invention is intended to cover non-exclusive inclusion, which does not exclude the presence of additional elements in a process, method, or product that includes the stated elements, such that a process, method, or product that includes a series of elements may include not only those defined elements but also other elements not expressly listed, or elements inherent to such a process, method, or product.

[0057] Similar to the understanding in the Examination Guidelines, in this utility model, expressions such as "greater than," "less than," and "exceeding" are understood to exclude the stated number; expressions such as "above," "below," and "within" are understood to include the stated number. Furthermore, in the description of the embodiments of this utility model, "multiple" means two or more (including two), and similar expressions related to "multiple" are also understood in this way, such as "multiple groups" and "multiple times," unless otherwise explicitly specified.

[0058] In the description of the embodiments of this utility model, the space-related expressions used, such as "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "vertical," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," indicate the orientation or positional relationship based on the orientation or positional relationship shown in the specific embodiments or drawings. They are only for the convenience of describing the specific embodiments of this utility model or for the reader's understanding, and do not indicate or imply that the device or component referred to must have a specific position, a specific orientation, or be constructed or operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this utility model.

[0059] Unless otherwise expressly specified or limited, the terms "installation," "connection," "linking," "fixing," and "setting," as used in the description of the embodiments of this utility model, should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral setting; it can be a mechanical connection, an electrical connection, or a communication connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two components or the interaction between two components. For those skilled in the art to which this utility model pertains, the specific meaning of the above terms in the embodiments of this utility model can be understood according to the specific circumstances.

[0060] See Figures 2-4 This utility model provides a series hot melt adhesive valve, comprising:

[0061] Valve body 1, wherein the valve body 1 is provided with a glue storage cavity 101 for storing hot melt glue and a hot melt glue inlet 102 connected to the glue storage cavity 101;

[0062] A glue cavity sealing assembly 2 is fixed inside the valve body 1 and is used to seal the upper opening of the glue storage cavity 101; wherein, the glue cavity sealing assembly 2 includes at least two glue cavity sealing elements 201 arranged in sequence.

[0063] The striking pin 3 slides from top to bottom through each of the glue cavity seals 201 and then extends into the glue storage cavity 101;

[0064] The hot melt adhesive supply component 9 has an outlet connected to the hot melt adhesive inlet 102 for supplying hot melt adhesive to the hot melt adhesive inlet 102.

[0065] The tandem hot melt adhesive valve provided in this embodiment operates as follows:

[0066] (1) After the hot melt adhesive supply assembly 9 heats and melts the hot melt adhesive, the hot melt adhesive is transported to the adhesive storage chamber 101 through the hot melt adhesive inlet 102 under the action of external air pressure.

[0067] (2) The actuator 8 drives the striker 3 to perform high-speed reciprocating motion;

[0068] (3) When the impact pin 3 moves downward, it squeezes the hot melt adhesive outward through the nozzle 5 to achieve dispensing;

[0069] Throughout the process, the impact pin 3 continuously slides through the seals 201 of each layer of glue cavity, forming a dynamic seal at the upper end of the glue storage cavity 101.

[0070] The series hot melt adhesive valve provided in this embodiment forms a multi-stage series sealing structure at the upper end of the adhesive storage cavity 101 by setting at least two sequentially stacked adhesive cavity seals 201.

[0071] Specifically, when the ejector pin 3 reciprocates, each layer of the adhesive cavity seal 201 forms a continuous dynamic sealing interface along its axial direction, creating a stepped pressure gradient between the adhesive cavity seal 201 and the ejector pin 3. In this structure, if the lower layer of the adhesive cavity seal 201 near the adhesive storage cavity 101 develops a gap due to long-term friction, the upper layer of the adhesive cavity seal 201 can still maintain an effective seal. This means that the hot melt adhesive leakage path needs to continuously break through multiple sealing barriers, significantly extending the gap accumulation time required for leakage to occur.

[0072] Meanwhile, the reverse air infiltration path is divided into multiple isolation sections by the multi-stage sealing structure. Even if there are micro gaps in a single-stage seal, the remaining sealing layer can still maintain the airtight state inside the glue storage cavity 101, preventing the hot melt adhesive from contacting the air and solidifying.

[0073] Therefore, the series hot melt adhesive valve provided by this utility model can effectively solve the problems of hot melt adhesive leakage and air backflow in existing hot melt dispensing valves.

[0074] In addition, the multi-stage sealing arrangement disperses the frictional load generated by the movement of the impact pin 3 to each sealing layer. Compared with the concentrated wear of a single-stage sealing structure, this design significantly improves the durability of the overall sealing structure through load sharing.

[0075] In this embodiment, the hot melt adhesive supply assembly 9 includes an adhesive storage cylinder 901 and a heating assembly 902. The adhesive storage cylinder 901 has a cavity 9011 that communicates with the hot melt adhesive inlet 102; the heating assembly 902 is fixed to the adhesive storage cylinder 901 and is used to heat and melt the hot melt adhesive in the cavity 9011.

[0076] Furthermore, the heating assembly 902 includes a heat transfer sleeve 9021 and a heating rod 9022. The heat transfer sleeve 9021 is sleeved on the outside of the glue storage cylinder 901; the heating rod 9022 is fixed to the side of the heat transfer sleeve 9021 and is thermally connected to the heat transfer sleeve 9021.

[0077] The heating rod 9022 heats the heat transfer sleeve 9021, which evenly transfers heat to the circumferential surface of the glue storage cylinder 901, thereby evenly transferring heat from the outside to the glue storage cylinder 901 and heating the hot melt glue inside the glue storage cylinder 901.

[0078] In this embodiment, the number of the cavity seals 201 is two. This optimized dual-stage sealing configuration satisfies the reliability requirements of multi-stage sealing while avoiding the increased frictional resistance caused by excessive sealing layers. The two-stage structure forms a reasonable pressure gradient distribution, ensuring sealing performance while minimizing the energy consumption of the impact pin 3, achieving the best balance between sealing performance and mechanical efficiency.

[0079] Of course, in some other embodiments, the number of cavity seals 201 may be three, four or even more, and this utility model does not limit this.

[0080] In this embodiment, the upper cavity seal (hereinafter referred to as "upper cavity seal 201") includes a seal body 2011, the seal body 2011 is provided with a cylindrical needle hole through which the impact pin 3 slides and passes; the bottom surface of the seal body 2011 is provided with an annular placement groove, and an inverted V-shaped preload spring 2012 is provided in the annular placement groove.

[0081] The inverted V-shaped preload spring 2012 is used to drive the wall of the cylindrical needle hole to press tightly against the impact pin 3, so as to improve the airtightness between the sealing body 2011 and the impact pin 3.

[0082] Furthermore, a pre-tensioning O-ring 2013 is provided at the V-shaped opening of the inverted V-shaped pre-tensioning spring 2012 to support the inverted V-shaped pre-tensioning spring 2012 outward, further driving the wall of the cylindrical needle hole to press tightly against the impact pin 3, thereby improving the airtightness between the sealing body 2011 and the impact pin 3.

[0083] By incorporating a sealing element body 2011 with a cylindrical needle hole, a dynamic sliding sealing interface is formed between the impact pin 3 and the sealing element, allowing each sealing layer to function independently. The cylindrical needle hole structure, while ensuring the free movement of the impact pin 3, forms an annular sealing band, effectively blocking the leakage path of hot melt adhesive. An inverted V-shaped preload spring 2012 generates radial preload, ensuring the inner wall of the sealing element remains tightly pressed against the surface of the impact pin 3, automatically compensating for wear gaps in the sealing element. This structure forms a dynamic self-adjusting sealing mechanism, maintaining stable contact pressure even after long-term use and wear of the sealing element, significantly extending the service life of the sealing assembly.

[0084] The pre-tightened O-ring 2013 enhances the pre-tightening effect on the cylindrical needle hole wall by expanding the inverted V-shaped spring outward. The dual-stage pre-tightening structure (spring + O-ring) generates superimposed radial pressure, making the contact pressure distribution on the sealing surface more uniform, especially improving the sealing fit at the microscopic unevenness of the impact pin 3 surface, forming a double anti-leakage barrier.

[0085] The lower layer of the adhesive cavity seal (hereinafter referred to as "lower layer adhesive cavity seal 202") includes an annular outer sleeve 2021 and a conical inner sleeve 2022 fixed inside the annular outer sleeve 2021 and surrounding a conical needle hole; wherein, the lower end of the conical inner sleeve 2022 extends into the adhesive storage cavity 101, and its diameter gradually decreases from top to bottom.

[0086] This structural design allows the adhesive material in the adhesive storage cavity 101 to automatically apply radial pressure from the outside to the inside to the lower end of the conical inner sleeve 2022, thereby enabling the inner wall of the lower end of the conical inner sleeve 2022 to fit tightly against the impact pin 3, thus improving airtightness.

[0087] Furthermore, the guide sleeve 7 used to install the impact pin 3 presses down on the upper cavity seal 201, so that the bottom surface of the pre-tightened O-ring 2013 abuts against the top surface of the conical inner sleeve 2022, thereby achieving a seal between the two cavity seals and preventing lateral leakage of hot melt adhesive.

[0088] Optionally, a leak-proof cavity 2023 is provided between the annular outer sleeve 2021 and the conical inner sleeve 2022. Even if a micro-leak occurs between the upper and lower adhesive cavity seals, the hot melt adhesive will be buffered in the leak-proof cavity 2023 and will not overflow directly, thus ensuring that other components will not be contaminated in the event of a micro-leak.

[0089] Optionally, a return spring 4 is fitted on the striking pin 3 to drive the striking pin 3 to slide upward. The series hot melt glue valve also includes an actuator 8 for driving the striking pin 3 to move downward, a nozzle 5 communicating with the glue storage chamber 101, and a threaded locking cap 6 for fixing the nozzle 5 to the bottom of the valve body 1.

[0090] The actuator 8 is located above the striker 3, and can be a piezoelectric ceramic, a cylinder piston, or an electromagnetic coil, etc. This embodiment does not limit this.

[0091] The return spring 4 forms an automatic rebound mechanism, ensuring that the ejector pin 3 remains in a high position when not in operation, thus preventing creep of the sealing surface caused by continuous pressure on the glue cavity. This design uses mechanical preload to counteract the internal pressure of the glue cavity, reducing the static load on the seal, while improving the response speed of the ejector pin 3 and enhancing the accuracy of the dispensing action.

[0092] The actuator 8 is designed for high-frequency, precise drive, accurately adjusting the hot melt adhesive extrusion volume by controlling the downward motion parameters (speed / stroke / frequency) of the striker 3. Working in conjunction with a multi-stage sealing structure, it ensures the dynamic stability of the sealing interface during high-speed reciprocating motion, meeting the process requirements of precision dispensing.

[0093] The threaded locking cap 6 forms a detachable nozzle 5 fixing structure, which not only ensures a reliable sealing connection between the nozzle 5 and the valve body 1, but also facilitates quick replacement of the nozzle 5 during maintenance. The thread preload establishes a uniform end face seal, effectively preventing high-pressure hot melt adhesive from leaking from the root of the nozzle 5, while maintaining the coaxiality accuracy of the dispensing port.

[0094] In summary, the series-connected hot melt adhesive valve provided in this embodiment has the following advantages:

[0095] ① Multi-stage series sealing structure: A stepped dynamic seal is formed by stacked adhesive cavity seals 201, which greatly extends the gap accumulation time required for hot melt adhesive leakage and air backflow.

[0096] ② Inverted V-shaped preload spring 2012 + O-ring: Dual-stage radial preload automatically compensates for seal wear, improves sealing surface fit and forms a double leak-proof barrier.

[0097] ③ Conical inner sleeve 2022 design: The conical structure design of the conical inner sleeve 2022 allows the adhesive material in the adhesive storage cavity 101 to automatically apply radial pressure to the lower end of the conical inner sleeve 2022 from the outside to the inside, thereby improving airtightness.

[0098] Finally, it should be noted that although the above embodiments have been described in the text and drawings of this application, this should not limit the scope of patent protection of this application. Any technical solutions that are based on the essential concept of this application and utilize the content described in the text and drawings of this application, resulting in equivalent structural or procedural substitutions or modifications, as well as the direct or indirect application of the technical solutions of the above embodiments to other related technical fields, are all included within the scope of patent protection of this application.

Claims

1. A series-connected hot melt adhesive valve, characterized in that, include: The valve body (1) has a storage cavity (101) for storing hot melt adhesive and a hot melt adhesive inlet (102) connected to the storage cavity (101). A cavity sealing assembly (2) is fixed inside the valve body (1) and is used to seal the upper opening of the glue storage cavity (101); wherein the cavity sealing assembly (2) includes at least two cavity sealing elements (201) stacked in sequence. The striking pin (3) slides from top to bottom through each of the glue cavity seals (201) and then extends into the glue storage cavity (101); Hot melt adhesive supply assembly (9), the outlet of the hot melt adhesive supply assembly (9) is connected to the hot melt adhesive inlet (102) for supplying hot melt adhesive to the hot melt adhesive inlet (102).

2. The series-connected hot melt adhesive valve according to claim 1, characterized in that, The number of the cavity seals (201) is two.

3. The series-connected hot melt adhesive valve according to claim 2, characterized in that, The upper cavity seal includes a seal body (2011), which has a cylindrical needle hole through which the striker (3) slides and seals. The bottom surface of the sealing body (2011) is provided with an annular groove, and an inverted V-shaped preload spring (2012) is provided in the annular groove. The inverted V-shaped preload spring (2012) is used to drive the cylinder through the hole wall of the needle hole to fit tightly against the striking pin (3).

4. The series-connected hot melt adhesive valve according to claim 3, characterized in that, The inverted V-shaped preload spring (2012) has a preload O-ring (2013) at the V-shaped opening, which is used to support the inverted V-shaped preload spring (2012) outward.

5. The series-connected hot melt adhesive valve according to claim 2, characterized in that, The lower cavity seal includes an annular outer sleeve (2021) and a conical inner sleeve (2022) fixed inside the annular outer sleeve (2021) and surrounding it to form a conical needle hole. The lower end of the conical inner sleeve (2022) extends into the glue storage cavity (101), and its diameter gradually decreases from top to bottom.

6. The series-connected hot melt adhesive valve according to claim 5, characterized in that, A leak-proof cavity (2023) is provided between the annular outer sleeve (2021) and the conical inner sleeve (2022).

7. The series-connected hot melt adhesive valve according to claim 1, characterized in that, The hot melt adhesive supply assembly (9) includes: The glue storage cylinder (901) is provided with a cylinder cavity (9011) connected to the hot melt glue inlet (102). Heating component (902), which is fixed to the glue storage cylinder (901), is used to heat and melt the hot melt glue in the cylinder cavity (9011).

8. The series-connected hot melt adhesive valve according to claim 7, characterized in that, The heating assembly (902) includes: A heat transfer sleeve (9021) is fitted over the outside of the glue storage cylinder (901); The heating rod (9022) is fixed to the side of the heat transfer sleeve (9021) and is thermally connected to the heat transfer sleeve (9021).

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