CN217842984U

CN217842984U - Double-press sleeve type sealing structure and vacuum reflow soldering furnace

Info

Publication number: CN217842984U
Application number: CN202222172212.0U
Authority: CN
Inventors: 许建国
Original assignee: Chengdu Gongyiyuan Vacuum Equipment Co ltd
Current assignee: Chengdu Gongyiyuan Vacuum Equipment Co ltd
Priority date: 2022-08-16
Filing date: 2022-08-16
Publication date: 2022-11-18
Anticipated expiration: 2032-08-16

Abstract

The application discloses two press shell type seal structure and vacuum reflow soldering stove, including the vacuum chamber wall, it is provided with the pipe to run through on the vacuum chamber wall, the cover is equipped with two sets of seal cover components that are located the inboard and the outside of vacuum chamber wall respectively on the pipe, the interval has between two sets of seal cover components, and two sets of seal cover components, enclose into sealed clearance between pipe and the vacuum chamber wall, set up the pressure release passageway with sealed clearance intercommunication in the vacuum chamber wall, the pressure release passageway other end communicates with the inboard of vacuum chamber wall, be provided with pressure release ball in the pressure release passageway, pressure release ball can remove in pressure release passageway, pressure release ball makes sealed clearance and vacuum chamber wall inboard switch on when being the negative pressure for the vacuum chamber wall inboard, this application has the pressure release effect, can reach vacuum state's advantage fast in the vacuum chamber.

Description

Double-press sleeve type sealing structure and vacuum reflow soldering furnace

Technical Field

The application relates to the technical field of vacuum reflow soldering, in particular to a double-press sleeve type sealing structure and a vacuum reflow soldering furnace.

Background

Vacuum reflow soldering, also called vacuum/controlled atmosphere eutectic furnace, has large thermal capacity and extremely small temperature difference of PCB surface, and is widely applied to the fields of Europe and America aviation, aerospace, military industry and electronics and the like. The infrared radiation heating principle is adopted, the welding machine has the characteristics of uniform and consistent temperature, ultralow-temperature safe welding, no temperature difference, no overheating, reliable and stable process parameters, no need of complex process tests, low environmental protection cost operation and the like, and meets the requirements of military products on various welding, small-batch welding and high reliability.

The main part of the vacuum reflow soldering is a vacuum chamber, each part of the vacuum chamber is provided with a plurality of conduits such as gas-filled tubes and vacuum connector tubes, the conduits penetrate through the inside and outside of the vacuum chamber, and the connecting part of the conduits and the chamber body is provided with a sealing structure to ensure the sealing property. In the prior art, a sealing sleeve and a plurality of sealing rings are sleeved between a guide pipe and a cabin body to form a sealing structure, but in the practical use process, when the vacuum state in the cabin needs to be switched, especially when the pressure in the vacuum cabin is converted from low vacuum to high vacuum, the pressure in the vacuum cabin is greater than the deformation sealing pressure of the sealing rings, the gas in the sealing area between the sealing rings can be slowly released to the cabin side, so that the high vacuum can be achieved in the vacuum cabin after the gas in the sealing area between the sealing rings is discharged, the high vacuum can be achieved, but in practice, the pressure existing in the sealing area between the sealing rings cannot be released, so that the vacuum state in the vacuum cabin is difficult to achieve quickly, the vacuumizing time is very long, and the production process and the production efficiency of a user cannot be met.

SUMMERY OF THE UTILITY MODEL

The main aim of this application is to provide a two press shell type seal structure and vacuum reflow oven, aim at solving the technical problem that the seal structure of current vacuum chamber and pipe is difficult to make the vacuum chamber in reach vacuum state fast.

In order to achieve the purpose, the application provides a double-press sleeve type sealing structure which comprises a vacuum cabin wall, wherein a guide pipe penetrates through the vacuum cabin wall, two groups of sealing sleeve assemblies respectively located on the inner side and the outer side of the vacuum cabin wall are sleeved on the guide pipe, a distance is reserved between the two groups of sealing sleeve assemblies, a sealing gap is defined between the guide pipe and the vacuum cabin wall, a pressure release channel communicated with the sealing gap is formed in the vacuum cabin wall, the other end of the pressure release channel is communicated with the inner side of the vacuum cabin wall, a pressure release ball is arranged in the pressure release channel and can move in the pressure release channel, and the sealing gap is communicated with the inner side of the vacuum cabin wall when the inner side of the vacuum cabin wall is negative pressure.

Alternatively, the pressure release passage includes a first passage and a second passage which are communicated with each other and perpendicular, the first passage is communicated with the seal gap, the second passage is communicated with the inside of the vacuum chamber wall, and the pressure release ball is movable only in the second passage.

Optionally, the second passage includes a first through hole communicating with the first passage, the first through hole communicates with a second through hole communicating with an inner side of the vacuum chamber wall, the pressure release ball is movable only within the second through hole, a diameter of the pressure release ball is smaller than a diameter of the second through hole, and the diameter of the pressure release ball is larger than a diameter of the first through hole.

Optionally, a gland is disposed on an inner wall of the vacuum bulkhead near the second through hole, a via hole communicated with the second through hole is disposed in the gland, and a diameter of the via hole is smaller than a diameter of the pressure release ball.

Optionally, an end of the second through hole adjacent to the first through hole is provided with a spherical sealing surface cooperating with the pressure release ball.

Optionally, the sealing sleeve assembly comprises a pressing sleeve seat sleeved on the conduit, one end of the pressing sleeve seat is embedded into the vacuum bulkhead, the other end of the pressing sleeve seat is provided with a pressing sleeve, and a sealing ring is arranged between the pressing sleeve and the pressing sleeve seat.

Optionally, the seal cartridge assembly further comprises a threaded sleeve simultaneously sleeved on the pressing sleeve and the pressing sleeve seat, the threaded sleeve is in threaded connection with the pressing sleeve seat, and the threaded sleeve is used for pressing the pressing sleeve to the end of the pressing sleeve seat.

Optionally, one end of the pressing sleeve, which is far away from the pressing sleeve seat, is provided with a step groove, and one end of the threaded sleeve is provided with a boss matched with the step groove.

Optionally, an inner tapered groove is formed in one end, close to the pressing sleeve, of the pressing sleeve seat, and the sealing ring is located in the inner tapered groove.

A vacuum reflow oven comprises the double-press sleeve type sealing structure.

The beneficial effect that this application can realize is as follows:

this application comes to seal the inboard of vacuum bulkhead inside and outside through setting up two sets of sealed cover subassemblies, simultaneously at the inside sealed clearance that forms of vacuum bulkhead, sealed clearance is used for forming the pressure release space, and pass through the inboard intercommunication of pressure release passageway and vacuum bulkhead with sealed clearance, when vacuum bulkhead inboard is vacuum negative pressure environment, cabin internal pressure is less than cabin external pressure promptly, make pressure release ball move towards the under-deck direction, thereby make sealed clearance and the inboard conduction of vacuum bulkhead, can not form the slow leakage phenomenon in sealed clearance, thereby can let the vacuum chamber in reach vacuum state fast, thereby reduce the evacuation time, and the work efficiency is improved.

Drawings

In order to more clearly illustrate the detailed description of the present application or the technical solutions in the prior art, the drawings that are required in the detailed description of the present application or the technical solutions in the prior art will be briefly described below. Throughout the drawings, like elements or portions are generally identified by like reference numerals. In the drawings, elements or portions are not necessarily drawn to scale.

Fig. 1 is a schematic structural view of a double-boot seal structure in an embodiment of the present application;

FIG. 2 is a schematic diagram of a second channel in an embodiment of the present application;

fig. 3 is a schematic structural diagram of a vacuum reflow oven in an embodiment of the present application (the sealing sleeve assembly is omitted).

Reference numerals:

100-vacuum bulkhead, 200-conduit, 300-sealing sleeve assembly, 310-pressure sleeve seat, 311-internal tapered groove, 320-pressure sleeve, 321-step groove, 330-sealing ring, 340-thread sleeve, 400-sealing gap, 500-pressure release channel, 510-first channel, 520-second channel, 521-first through hole, 522-second through hole, 5221-spherical sealing surface, 600-pressure release ball, 700-gland.

The implementation, functional features and advantages of the objectives of the present application will be further explained with reference to the accompanying drawings.

Detailed Description

The technical solutions in the embodiments of the present application will be described clearly and completely with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

It should be noted that all the directional indicators (such as upper, lower, left, right, front, and rear … …) in the present embodiment are only used to explain the relative position relationship between the components, the movement situation, and the like in a specific posture, and if the specific posture is changed, the directional indicator is changed accordingly.

In this application, unless expressly stated or limited otherwise, the terms "connected," "secured," and the like are to be construed broadly, and for example, "secured" may be a fixed connection, a removable connection, or an integral part; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.

In addition, if there is a description of "first", "second", etc. in the embodiments of the present application, the description of "first", "second", etc. is for descriptive purposes only and is not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In addition, the meaning of "and/or" appearing throughout includes three juxtapositions, exemplified by "A and/or B" including either A or B or both A and B. In addition, technical solutions between various embodiments may be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present application.

Example 1

Referring to fig. 1-2, the present embodiment provides a double-press-sleeve type sealing structure, which includes a vacuum bulkhead 100, a conduit 200 is disposed through the vacuum bulkhead 100, two sets of sealing gland assemblies 300 respectively disposed on an inner side and an outer side of the vacuum bulkhead 100 are sleeved on the conduit 200, a gap is defined between the two sets of sealing gland assemblies 300, the conduit 200 and the vacuum bulkhead 100, a sealing gap 400 is defined between the two sets of sealing gland assemblies 300, the vacuum bulkhead 100 is provided with a pressure release passage 500 communicating with the sealing gap 400, the other end of the pressure release passage 500 is communicated with the inner side of the vacuum bulkhead 100, a pressure release ball 600 is disposed in the pressure release passage 500, the pressure release ball 600 is movable in the pressure release passage 500, and the pressure release ball 600 is used for communicating the sealing gap 400 with the inner side of the vacuum bulkhead 100 when a negative pressure is applied to the inner side of the vacuum bulkhead 100.

In this embodiment, two sets of seal sleeve assemblies 300 are provided to seal the inside and the outside of the vacuum bulkhead 100, and simultaneously, a seal gap 400 is formed inside the vacuum bulkhead 100, the seal gap 400 is used to form a pressure release space, and the seal gap 400 is communicated with the inside of the vacuum bulkhead 100 through a pressure release channel 500, when the inside of the vacuum bulkhead 100 is a vacuum negative pressure environment, that is, the pressure inside the vacuum bulkhead is smaller than the pressure outside the vacuum cabin, so that the pressure release ball 600 moves toward the inside of the vacuum cabin, and thus the seal gap 400 is communicated with the inside of the vacuum bulkhead 100, and a slow leakage phenomenon of the seal gap 400 is not formed, so that the vacuum state inside the vacuum cabin can be quickly reached, thereby reducing the vacuum pumping time and improving the working efficiency.

It should be noted that the conduit 200 includes all the pipes which are communicated with the vacuum chamber body and have the sealing requirement, and the sealing structure of the present application can be adopted when other pipes have the sealing requirement.

As an alternative embodiment, the pressure relief passage 500 includes a first passage 510 and a second passage 520 that are perpendicular to each other, the first passage 510 communicates with the seal gap 400, the second passage 520 communicates with the inside of the vacuum bulkhead 100, and the pressure relief ball 600 is movable only in the second passage 520.

In the present embodiment, the pressure release channel 500 is divided into two vertical first channels 510 and second channels 520, which are connected to each other, so that the pressure release ball 600 can move in the second channel 520 toward or away from the first channel 510 under the positive or negative pressure of the vacuum chamber to release the pressure, and simultaneously, the second channel 520 is connected to the inner side of the vacuum chamber wall 100, which is beneficial to rapidly achieve the vacuum state in the vacuum chamber.

As an alternative embodiment, the second passage 520 includes a first through hole 521 communicating with the first passage 510, the first through hole 521 communicates with a second through hole 522 communicating with the inside of the vacuum bulkhead 100, the pressure release ball 600 is movable only in the second through hole 522, the diameter of the pressure release ball 600 is smaller than that of the second through hole 522, and the diameter of the pressure release ball 600 is larger than that of the first through hole 521.

In the present embodiment, the second channel 520 is optimally designed, when the pressure inside the chamber is positive, the pressure release ball 600 moves towards the outside of the chamber (i.e. moves towards the direction close to the first channel 510) until the pressure release ball 600 blocks the end of the first through hole 521, and when the pressure is released, the pressure release ball 600 moves towards the inside of the chamber (i.e. moves away from the first channel 510), and when the inside of the chamber is a vacuum environment (i.e. negative pressure inside the chamber), the pressure release ball 600 has a further sealing function, and because the diameter of the pressure release ball 600 is smaller than that of the second through hole 522, the whole second channel 520 is communicated with the first channel 510 and the sealing gap 400, so that the sealing gap 400 is communicated with the inside of the vacuum chamber wall 100, and the sealing gap 400 does not form a slow leakage phenomenon, thereby enabling the vacuum inside of the vacuum chamber to quickly reach a vacuum state.

As an alternative embodiment, the inner wall of the vacuum bulkhead 100 near the second through hole 522 is provided with a gland 700, and the gland 700 is provided with a through hole communicating with the second through hole 522, and the diameter of the through hole is smaller than that of the pressure release ball 600.

In the present embodiment, the gland 700 is used to prevent the pressure releasing ball 600 from sliding out of the second through hole 522, and the through hole in the gland 700 can keep the communication between the cabin and the sealing gap 400, and it should be noted that when the pressure releasing ball 600 moves to block the through hole of the gland 700, the pressure releasing is completed and the automatic sealing is performed at the same time, and at this time, the cabin has reached a vacuum state and does not need to communicate with the sealing gap 400 any more.

As an alternative embodiment, one end of the second through hole 522 close to the first through hole 521 is provided with a spherical sealing surface 5221 matched with the pressure release ball 600, and the pressure release ball 600 has a good fit with the spherical sealing surface 5221, so that the pressure release ball 600 has good sealing performance when blocking the first through hole 521.

As an alternative embodiment, the sealing sleeve assembly 300 includes a pressing sleeve seat 310 sleeved on the conduit 200, one end of the pressing sleeve seat 310 is embedded in the vacuum bulkhead 100, the other end of the pressing sleeve seat 310 is provided with a pressing sleeve 320, and a sealing ring 330 is arranged between the pressing sleeve 320 and the pressing sleeve seat 310.

In this embodiment, when the vacuum chamber is at positive pressure or negative pressure, the pressure acts on the corresponding pressure sleeve 320, and thus acts on the corresponding sealing ring 330, and based on the structural form of the two sets of sealing sleeve assemblies 300 and in combination with the structure of the pressure release channel 500, the vacuum chamber has a good pressure release effect, which can reduce the extrusion deformation of the sealing ring 330, and simultaneously can quickly reach a vacuum state in the vacuum chamber, and the specific principle is as follows (the sealing ring 330 located in the chamber is a sealing ring a, and the sealing ring 330 located outside the chamber is a sealing ring B):

1. indoor positive pressure (when higher than one atmosphere)

(1) When the pressure in the cabin is positive, the pressure acts on the sealing ring A and the pressure release ball 600, and the sealing ring A is stressed on the outer side, so that the sealing performance is increased along with the increase of the pressure in the cabin;

(2) The pressure is transmitted to the pressure release ball 600 through the via hole of the gland 700, the pressure release ball 600 moves towards the outboard direction, the spherical surface of the pressure release ball 600 is attached to the spherical sealing surface to achieve sealing, and therefore the sealing performance is increased along with the increase of the pressure in the cabin;

(3) When the pressure in the cabin is increased, because of the sealing performance of the sealing ring A and the pressure release ball 600, the pressure in the sealing area (namely the sealing gap 400) between the sealing ring A and the sealing ring B cannot be increased along with the increase of the pressure in the cabin, so that the pressure acting on the sealing ring B is not influenced by the pressure in the cabin, and the sealing ring B cannot be extruded and deformed outwards due to the reaction force under the action of the pressure of the pressing sleeve 320, thereby improving the fatigue resistance of the sealing ring B.

2. When the pressure in the cabin is low vacuum/high vacuum

(1) When the vacuum chamber is in low vacuum or high vacuum, namely the pressure in the chamber is less than the pressure in the sealing area of the sealing ring A and the sealing ring B, the pressure release ball 600 moves towards the direction in the chamber to conduct the vacuum chamber and the sealing gap 400, so that the slow leakage phenomenon of the sealing gap 400 can not be formed, and the vacuum chamber can quickly reach a vacuum state;

(2) The vacuum chamber is communicated with the sealing gap 400, the two sides of the sealing ring A are stressed in a balanced manner, and the sealing ring A cannot be extruded and deformed outwards due to the reaction force under the pressure action of the pressing sleeve 320, so that the fatigue resistance of the sealing ring A is improved.

(3) The vacuum chamber is communicated with the sealing gap 400, the sealing ring B is in a vacuum state on the inner side of the chamber, the outside of the chamber is in atmospheric pressure, the higher the vacuum degree of the inner side of the chamber is, the larger the pressure difference between the outer side (atmosphere) and the inner side (vacuum chamber) of the sealing ring B is, the better the sealing performance of the sealing ring B is, and therefore the vacuum state can be quickly and stably achieved in the vacuum chamber.

As an optional implementation manner, the seal cartridge assembly 300 further includes a threaded sleeve 340 sleeved on the pressure sleeve 320 and the pressure sleeve seat 310, the threaded sleeve 340 is in threaded connection with the pressure sleeve seat 310, the threaded sleeve 340 is used for pressing the pressure sleeve 320 to the end of the pressure sleeve seat 310, when the threaded sleeve 340 is screwed in, the pressure sleeve 320 can be conveniently pressed to the end of the pressure sleeve seat 310, so that the assembly and disassembly are convenient, and the operation is convenient and fast.

As an optional implementation manner, a stepped groove 321 is formed in one end of the pressing sleeve 320, which is away from the pressing sleeve seat 310, a boss matched with the stepped groove 321 is arranged at one end of the threaded sleeve 340, and through a limiting structure of the stepped groove 321 and the boss and a thread self-locking effect of the threaded sleeve 340, the assembled sealing sleeve assembly 300 is firm and stable in structure and good in sealing performance.

As an alternative embodiment, an end of the pressing sleeve seat 310 close to the pressing sleeve 320 is provided with an inner tapered groove 311, the sealing ring 330 is located in the inner tapered groove 311, and the inner tapered groove 311 is used for providing a receiving space for the sealing ring 330 and reducing the extrusion deformation.

Example 2

Referring to fig. 1 to 3, the present embodiment provides a vacuum reflow soldering oven, which includes the double-press-sleeve type sealing structure described in embodiment 1, so that the vacuum reflow soldering oven can be more suitable for a positive-negative pressure soldering process, and has good sealing performance and long service life.

The above description is only a preferred embodiment of the present application, and not intended to limit the scope of the present application, and all modifications of equivalent structures and equivalent processes, which are made by the contents of the specification and the drawings of the present application, or which are directly or indirectly applied to other related technical fields, are included in the scope of the present application.

Claims

1. A double-press-sleeve type sealing structure is characterized by comprising a vacuum bulkhead, wherein a guide pipe penetrates through the vacuum bulkhead, two groups of sealing sleeve assemblies which are respectively positioned on the inner side and the outer side of the vacuum bulkhead are sleeved on the guide pipe, a space is reserved between the two groups of sealing sleeve assemblies, a sealing gap is formed by the two groups of sealing sleeve assemblies, the guide pipe and the vacuum bulkhead in a surrounding mode, a pressure release channel communicated with the sealing gap is formed in the vacuum bulkhead, the other end of the pressure release channel is communicated with the inner side of the vacuum bulkhead, a pressure release ball is arranged in the pressure release channel and can move in the pressure release channel, and the pressure release ball is used for enabling the sealing gap to be communicated with the inner side of the vacuum bulkhead when the inner side of the vacuum bulkhead is negative pressure.

2. A double-press-boot seal structure according to claim 1, wherein said pressure release passage comprises a first passage and a second passage which are in communication with each other and perpendicular, said first passage being in communication with said seal gap, said second passage being in communication with an inner side of said vacuum chamber wall, said pressure release ball being movable only in said second passage.

3. A double-press boot seal structure according to claim 2, wherein said second passage includes a first through hole communicating with said first passage, said first through hole communicating with a second through hole communicating with an inner side of said vacuum chamber wall, said pressure release ball being movable only within said second through hole, said pressure release ball having a diameter smaller than a diameter of said second through hole and said pressure release ball having a diameter larger than a diameter of said first through hole.

4. A double press-fit seal structure according to claim 3, wherein the inner wall of the vacuum bulkhead near the second through-hole is provided with a gland, and a through-hole communicating with the second through-hole is provided in the gland, and the diameter of the through-hole is smaller than that of the pressure release ball.

5. A double press-fit seal arrangement according to claim 3, wherein the end of said second through-hole adjacent said first through-hole is provided with a spherical sealing surface for engagement with said pressure relief ball.

6. The double press sleeve type sealing structure as claimed in any one of claims 1 to 5, wherein the sealing sleeve assembly includes a press sleeve seat sleeved on the conduit, one end of the press sleeve seat is embedded in the vacuum chamber wall, the other end of the press sleeve seat is provided with a press sleeve, and a sealing ring is arranged between the press sleeve and the press sleeve seat.

7. A double press sleeve type sealing structure as set forth in claim 6, wherein said sealing sleeve assembly further comprises a threaded sleeve simultaneously sleeved on said press sleeve and said press sleeve seat, said threaded sleeve being in threaded connection with said press sleeve seat, said threaded sleeve being used for pressing said press sleeve against the end of said press sleeve seat.

8. The double-press sleeve type sealing structure as claimed in claim 7, wherein a stepped groove is formed at an end of the press sleeve away from the press sleeve seat, and a boss which is matched with the stepped groove is formed at an end of the threaded sleeve.

9. A double press sleeve type sealing structure according to claim 7, wherein an inner tapered groove is formed at one end of the press sleeve seat close to the press sleeve, and the sealing ring is located in the inner tapered groove.

10. A vacuum reflow oven, comprising a double-press-sleeve sealing structure according to any one of claims 1 to 9.