CN108237293B

CN108237293B - Integral updraft ventilator

Info

Publication number: CN108237293B
Application number: CN201611217142.9A
Authority: CN
Inventors: 詹姆斯·内维尔; 大卫·海乐; 李占斌
Original assignee: Heller Shanghai Co ltd
Current assignee: Heller Shanghai Co ltd
Priority date: 2016-12-26
Filing date: 2016-12-26
Publication date: 2023-08-08
Anticipated expiration: 2036-12-26
Also published as: CN108237293A

Abstract

The invention relates to an integral type air draft device which is arranged in a hearth of a reflow oven and comprises an upper air draft box (1), a lower air draft box (2), an air draft tube (5) and an air draft motor, wherein the upper air draft box (1) is a box body with an opening at the lower part, the lower air draft box (2) is a box body with an opening at the upper part, the open ends of the upper air draft box (1) and the lower air draft box (2) are oppositely arranged and respectively fixed at the upper part and the lower part of the hearth, the open ends of the upper air draft box (1) and the lower air draft box (2) are fixedly connected through a connecting piece to form a sealing cavity, the air draft motor is connected with the air draft tube (5), and the air draft tube (5) is arranged below the lower air draft box (2) and is communicated with the sealing cavity. Compared with the prior art, the air draft device has the advantages of simple structure, good air draft effect and difficult damage to the PCB in the reflow soldering furnace.

Description

Integral updraft ventilator

Technical Field

The invention relates to an exhaust device, in particular to an integral exhaust device.

Background

Reflow ovens are a type of soldering equipment used in the SMT industry. The automatic and stable heating environment can be provided, so that the soldering paste in the hearth is heated and melted, and the electrical components pre-attached on the PCB and the PCB are reliably combined together through the soldering alloy.

After the soldering paste is heated and melted, part of the soldering flux in the soldering paste forms steam, and most of the soldering flux steam is pumped away from the hearth from the exhaust port; at present, an exhaust system used for a reflow soldering furnace is used for directly exhausting, and an upper exhaust pipeline is usually fixed on the upper part of a hearth, and a lower exhaust pipeline is fixed on the lower part of the hearth. Since flux vapors tend to condense on relatively low temperature surfaces, a small amount of flux liquefies and adheres to the suction port wall. When the liquid soldering flux is accumulated in the upper exhaust opening, liquid drops are formed and finally drop down, and the liquid soldering flux has a high probability of dropping on a circuit board (PCB), so that the quality of the customer circuit board is disqualified or even scrapped.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide an integral type air draft device.

The aim of the invention can be achieved by the following technical scheme:

an integral updraft ventilator installs in reflow oven's furnace, and the device includes updraft ventilator box, lower updraft ventilator box, exhaust column and exhaust motor, the updraft ventilator box be the open box body in below, the updraft ventilator box is the open box body in top down, the updraft ventilator box sets up relatively and fixes respectively in furnace upper and lower part with the open end of downdraft ventilator box, the updraft ventilator box forms sealed cavity with the open end of downdraft ventilator box through connecting piece fixed connection, the exhaust motor connect the exhaust column, the exhaust column set up in downdraft ventilator box below and communicate sealed cavity.

The upper exhaust box comprises an outer box body and an inner partition plate, wherein the outer box body is a box body with an opening at the lower end, the inner partition plate is arranged in two pieces, the inner partition plate is oppositely arranged in the outer box body and divides the outer box body into a first middle cavity and baffle cavities at two sides, and the upper part of the first middle cavity is communicated with the baffle cavities at two sides.

The inner partition plate comprises a vertical section and an inclined section, the inclined section is arranged above the vertical section and is inclined towards the middle axis direction of the upper exhaust box, the two inclined sections form an eight-shaped structure with an upper opening, and the opening above the inclined section is communicated with the baffle cavity and the first middle cavity.

The lower exhaust box inner structure and the upper exhaust box inner structure are symmetrically arranged, the lower exhaust box is provided with a second middle cavity and backflow cavities at two sides, the second middle cavity is communicated with the first middle cavity, the backflow cavities are communicated with the baffling cavities, and the second middle cavity is communicated with the backflow cavities at two sides.

The upper exhaust box and the lower exhaust box are internally provided with exhaust baffles, the exhaust baffles are horizontally arranged in the middle of the upper exhaust box and the lower exhaust box, and the width of each exhaust baffle is smaller than the width of the inner sides of the upper exhaust box and the lower exhaust box.

The air draft baffle is movably arranged in the upper air draft box and the lower air draft box.

Compared with the prior art, the invention has the following advantages:

(1) The air draft device is assembled to form an integral structure through the upper box body and the lower box body which are communicated up and down, only one air draft motor is needed to be adopted to draft air at the bottom, equipment is simplified, maintenance is convenient, and cost is reduced;

(2) The invention discloses an exhaust device which comprises a first middle cavity, a second middle cavity, a baffle cavity and a reflux cavity, wherein the first middle cavity and the second middle cavity are communicated with each other, the baffle cavity and the reflux cavity are communicated with each other, under the action of an exhaust motor, part of gas in a hearth goes upward, the other part of gas goes downward, the upward gas passes through the baffle cavity and is deflected through the first middle cavity, then flows to an exhaust tube below a lower exhaust box through the reflux cavity and is discharged, and the downward gas flow directly passes through the second middle cavity and flows to the exhaust tube and is discharged, so that the effective discharge of the gas in the hearth of a reflow soldering furnace is realized, even if a very small amount of steam is condensed into a liquid state in the lower exhaust box and is attached to the inner wall of the lower exhaust box, when the liquid soldering flux is accumulated to a certain degree, the liquid flux can flow downward along the inner wall of the lower exhaust box into the exhaust pipe orifice, and the PCB positioned at the middle part of the whole exhaust device is not damaged;

(3) The air draft baffle plate can be designed to have different widths according to the requirements, so that the air draft quantity of the upper air draft box and the lower air draft box is balanced, and the air draft effect is better.

Drawings

FIG. 1 is an assembly view of an integrated suction device of the present invention;

FIG. 2 is a flow diagram of the air in the integrated suction device of the present invention.

In the figure, 1 is an upper exhaust box, 2 is a lower exhaust box, 3 is an upper connecting plate, 4 is a lower connecting plate, and 5 is an exhaust pipe.

Detailed Description

The invention will now be described in detail with reference to the drawings and specific examples.

Examples

As shown in fig. 1, an integral type air extracting device is installed in a hearth of a reflow oven, the device comprises an upper air extracting box 1, a lower air extracting box 2, an air extracting tube 5 and an air extracting motor, the upper air extracting box 1 is a box body with an opening at the lower part, the lower air extracting box 2 is a box body with an opening at the upper part, the opening ends of the upper air extracting box 1 and the lower air extracting box 2 are oppositely arranged and respectively fixed at the upper part and the lower part of the hearth, the opening ends of the upper air extracting box 1 and the lower air extracting box 2 are fixedly connected through connecting pieces to form a sealing cavity, and the connecting pieces comprise an upper connecting plate 3 and a lower connecting plate 4 shown in fig. 1 and are fixed through fastening screws. The exhaust motor is connected with an exhaust pipe 5, and the exhaust pipe 5 is arranged below the lower exhaust box 2 and communicated with the sealing cavity.

The upper exhaust box 1 comprises an outer box body and an inner partition plate, wherein the outer box body is a box body with an opening at the lower end, the inner partition plate is provided with two inner partition plates, the inner partition plate is oppositely arranged in the outer box body and divides the outer box body into a first middle cavity and baffle cavities at two sides, and the upper part of the first middle cavity is communicated with the baffle cavities at two sides. The inner partition plate comprises a vertical section and an inclined section, the inclined section is arranged above the vertical section and inclines towards the middle axis direction of the air draft box 1, the two inclined sections form an splayed structure with an upper opening, and the opening of the baffling cavity and the opening of the first middle cavity above the inclined section are mutually communicated. The internal structure of the lower exhaust box 2 is symmetrically arranged with the internal structure of the upper exhaust box 1, the second middle cavity of the lower exhaust box 2 is communicated with the first middle cavity, the backflow cavity is communicated with the baffling cavity, and the backflow cavities on the second middle cavity and the two sides are communicated.

The inside updraft ventilator that all is equipped with of updraft ventilator 1 and downdraft ventilator 2, updraft ventilator level sets up at updraft ventilator 1 and downdraft ventilator 2 middle part, and updraft ventilator activity sets up in updraft ventilator 1 and downdraft ventilator 2, and updraft ventilator width is less than updraft ventilator 1 and downdraft ventilator 2 inboard width.

The working principle of the invention is as follows: under the effect of the exhaust motor, a part of gas in the hearth of the reflow soldering furnace goes upwards, a part of gas goes downwards, the concrete gas flow direction is shown in fig. 2, the upward gas flows through the baffling cavity after passing through the first middle cavity, then flows to the exhaust pipe 5 below the lower exhaust box 2 through the backflow cavity and is discharged, the downward gas flow directly flows to the exhaust pipe 5 through the second middle cavity and is discharged, the effective discharge of the gas in the hearth of the reflow soldering furnace is realized in this way, even if a small amount of steam is condensed into a liquid state in the lower exhaust box 2 and is attached to the inner wall of the lower exhaust box 2, when the liquid soldering flux is accumulated to a certain degree, the liquid soldering flux can flow downwards to the opening of the exhaust pipe 5 along the inner wall of the lower exhaust box 2, and the PCB positioned in the middle of the whole exhaust device is not damaged. Due to the adoption of the special design, the uniform air suction between the upper and lower parts can be ensured, and when the soldering flux steam is sucked by the upper air suction box 1, the soldering flux steam is finally discharged from the bottom air suction pipe 5, even if the soldering flux is agglutinated, the soldering flux can be agglutinated at the bottom of the air suction device, and cannot be collected at the upper air suction box 1, so that the possibility that the liquid soldering flux directly drops onto a PCB in a hearth can be effectively prevented. The customer can remove the small amount of flux collected here by making regular maintenance on the bottom suction tube 5.

Claims

1. The integral type air suction device is arranged in a hearth of a reflow oven and is characterized by comprising an upper air suction box (1), a lower air suction box (2), an air suction tube (5) and an air suction motor, wherein the upper air suction box (1) is a box body with an opening at the lower part, the lower air suction box (2) is a box body with an opening at the upper part, the open ends of the upper air suction box (1) and the lower air suction box (2) are oppositely arranged and respectively fixed at the upper part and the lower part of the hearth, the open ends of the upper air suction box (1) and the lower air suction box (2) are fixedly connected through a connecting piece to form a sealing cavity, the air suction motor is connected with the air suction tube (5), and the air suction tube (5) is arranged below the lower air suction box (2) and is communicated with the sealing cavity;

the upper exhaust box (1) comprises an outer box body and an inner partition plate, wherein the outer box body is a box body with an opening at the lower end, the inner partition plate is provided with two blocks, the inner partition plate is oppositely arranged in the outer box body and divides the outer box body into a first middle cavity and baffle cavities at two sides, and the upper part of the first middle cavity is communicated with the baffle cavities at two sides;

the inner partition plate comprises a vertical section and an inclined section, the inclined section is arranged above the vertical section and is inclined towards the middle axis direction of the upper exhaust box (1), the two inclined sections form an splayed structure with an opening at the upper part, and the opening of the baffling cavity and the opening of the first middle cavity above the inclined section are mutually communicated;

the inner structure of the lower exhaust box (2) is symmetrically arranged with the inner structure of the upper exhaust box (1), the lower exhaust box (2) comprises a second middle cavity and two reflux cavities at two sides, the second middle cavity is communicated with the first middle cavity, the reflux cavities are communicated with the baffling cavities, and the second middle cavity is communicated with the reflux cavities at two sides;

the upper exhaust box (1) and the lower exhaust box (2) are internally provided with exhaust baffles, the exhaust baffles are horizontally arranged in the middle of the upper exhaust box (1) and the lower exhaust box (2), and the width of each exhaust baffle is smaller than the width of the inner sides of the upper exhaust box (1) and the lower exhaust box (2).

2. An integrated suction device according to claim 1, characterized in that the suction baffle is movably arranged in the upper suction box (1) and the lower suction box (2).