JP3374591B2 - Low-temperature melt recovery equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a low-temperature melt recovery apparatus capable of appropriately recovering a substance that melts at a low temperature, such as lead, which is used for soldering printed boards.

[0002]

2. Description of the Related Art In recent years, environmental pollution due to metals has become a problem worldwide. By the way, in Japan, waste materials such as home electric appliances are currently crushed and processed as so-called shredder dust. Heavy metals are used for solder and the like in printed circuit boards for such home electric appliances. Therefore, if a safer method is taken against the problems such as environmental pollution, it is desirable to separate and remove these metals from such a printed circuit board before the landfill disposal.

As a method for separating and removing the metal such as the solder, the following method is considered. First, a method is considered in which a metal such as solder is melted and separated and removed by heating shredder dust.
In addition, a method in which metal such as solder is melted and separated and removed by heating before crushing into shredder dust may be considered. Furthermore, a basic method of directly separating and removing metal such as solder of a printed substrate from human waste by hand is also considered.

[0004]

However, in any of the methods, there is a problem that the metal such as solder cannot be properly separated and removed. For example, in the method of heating the shredder dust, not only is there a danger of explosion due to the heating of the dust, but the metal such as molten solder gradually melts and penetrates into the shredder dust, Separation and removal took time, and the separation and removal efficiency was poor. Also, in the method of heating before shredding into shredder dust, similarly, molten metal such as solder diffuses into waste such as home electric appliances, so it takes time to separate and remove, and separation and removal efficiency also increases. It was bad. Further, in the method of directly removing the metal manually, not only the efficiency of separation and removal is poor, but there is a risk of affecting the health of the worker.

Therefore, an object of the present invention is to properly remove metal such as solder from waste such as home electric appliances, that is, in a short time with a high recovery rate without affecting the health of workers. An object of the present invention is to provide a low-temperature melt recovery device capable of recovering.

[0006]

In order to solve the above problems, a high temperature gas is jetted onto a printed circuit board at a high pressure,
Metals such as solder were melted and blown off to separate them. Further, the gas is jetted to the printed circuit boards that are sequentially conveyed so that the separation process can be continuously performed on the plurality of printed circuit boards.

Therefore, the low-temperature melt recovery apparatus of the present invention comprises a casing having a printed board carry-in port, a printed board discharge port, an inert gas introduction port, an inert gas discharge port, and a melt discharge port, and A first flat portion provided between the printed circuit board carry-in port and the printed circuit board discharge port and connected to the printed circuit board carry-in port; a lower inclined portion whose lower end is located at the melt discharge port; A conveyance path provided with a second flat portion connected to the printed board discharge port continuously, and a printed circuit board to which the low-temperature melt is admitted from the printed board carry-in port are conveyed along the conveyance path. Transporting means for leading to the printed circuit board outlet,
A preheating unit that is provided near the first flat portion and injects a gas at a predetermined temperature at a predetermined pressure to preheat the printed circuit board; Hot jet means for injecting at a pressure to melt and remove the low-temperature melt adhered to the printed circuit board.

[0008] Preferably, the low-temperature melt recovery apparatus of the present invention further comprises cooling means provided near the second flat portion and for lowering the temperature of the printed circuit board to a predetermined temperature.

Specifically, the hot jet means is
A gas at about 250 ° C to 1000 ° C is injected.

More specifically, the hot jet means injects a gas having a pressure of about 3 [Kg / cm ² ] or more.

[0011]

According to the low-temperature melt recovery apparatus of the present invention, the printed circuit board to which the low-temperature melt is attached is sequentially moved by the transfer means on the transfer path. At that time, the printed circuit board is gradually heated by injecting a gas of a predetermined temperature by the preheating means, and is injected by the hot jet means at a high pressure with a high temperature gas, and the adhered metal is melted, blown away, and removed. . These treatments are carried out in the inert gas introduced through the inert gas inlet and discharged through the inert gas outlet. Further, the removed low temperature melt is discharged from the melt discharge port.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the low temperature melt recovery apparatus of the present invention will be described with reference to FIGS. The present embodiment is a metal separation and recovery device for recovering low temperature molten metal such as solder from a printed circuit board. FIG. 1 is a diagram showing the configuration centering on the printed circuit board processing system of the low temperature molten metal recovery apparatus of this embodiment. FIG. 2 is a diagram showing the configuration centered on the control system of the low temperature molten metal recovery apparatus of this embodiment.

First, the low temperature molten metal recovery apparatus 1 of this embodiment
00 will be described. The low temperature molten metal recovery apparatus 100 of the present embodiment includes a printed circuit board processing system centering on the components inside the heat insulating casing 110, a gas control system provided outside the heat insulating casing 110, and each of these parts and the entire device. A control / operation unit for controlling is provided in the device casing 101. The configuration of each unit will be described below.
First, the printed circuit board processing system includes a preheating unit 130, a separation heating unit 140, and a cooling unit 1 in a heat insulating casing 110.
It is a structure having 50. Then, the rotary conveyor 120 is arranged so that the printed circuit board sequentially passes between the respective parts.
Is provided.

The heat-insulating housing 110 is a housing having the above-mentioned components inside and having a heat-insulating function for preventing heat transfer to the outside due to high temperature treatment of the components. An inert gas is circulated in the heat insulating casing 110. In this heat insulating casing 110, a substrate carry-in port 111, a substrate discharge port 112, a separation discharge port 113, an inert gas introduction port 114,
Also, five openings of the gas outlet 115 are provided.

The substrate carry-in port 111 is provided in the upper part of the side surface of the heat insulating casing 110, and the rotary conveyor 120 is provided so as to be inserted into the substrate carry-in port 111 toward the inside of the casing. An air seal 1 is provided at the substrate loading port 111.
16 is provided to isolate the heat insulating casing 110 from the outside and the inside. The substrate discharge port 112 is provided in the lower portion of the side surface of the heat insulating casing 110 facing the substrate inlet 111, and the rotary conveyor 120 is provided toward the outside of the casing while being inserted into the substrate discharge port 112. ing. An air seal 117 is provided at the substrate discharge port 112 to isolate the heat insulating casing 110 from the outside.

The separation / exhaust port 113 stores the metal separated by the separation / heating unit 140 in the heat insulating casing 110.
It is an opening for discharging to the outside. Inert gas inlet 11
4 and the gas outlet 115 are the gas inlet and the outlet for flowing the inert gas into the heat insulating casing 110 as described above, and the inert gas inlet 114 is the gas regulator 160 outside the heat insulating casing 110. It is connected to the.

The rotary conveyor 120 mounts the printed circuit board
It is a conveying device for passing the inside of the heat insulating casing 110 of the low-temperature molten metal recovery device 100, and has a rotation round system. Further, the carousel 120 is in a mesh state, and for example, when a component mounted on a printed circuit board is melted and becomes a liquid, it is directly melted out to the lower portion of the low temperature molten metal recovery device 100. .
Further, the carousel 120 is divided into a basket shape, and the printed circuit board is automatically conveyed thereafter simply by placing it on the basket portion.

The carousel 120 is horizontally extended from the outside of the heat insulating casing 110 to the inside of the heat insulating casing 110 from a substrate loading port 111 provided at the upper portion of the heat insulating casing 110. In the separating and heating unit 140 inside 110, it is obliquely extended downward at a predetermined angle, returns to the horizontal direction again, and extends from the substrate discharge port 112 of the heat insulating casing 110 to the outside of the heat insulating casing 110. The rotary conveyor 120 is driven by the rotation of the motor 121. The motor 121 has a rotation sensor (not shown), and the speed of the rotation conveyor 120 is controlled by the rotation control unit 183 of the controller 180 based on the detection result of the rotation sensor.

The preheating unit 130 is a means for preheating the input printed circuit board in order to prevent the mounted components on the printed circuit board from being destroyed more than necessary. Preheating unit 130
Is configured in the vicinity of the substrate inlet 111 of the carousel 120, and the preheated air injector 131 is used to drive the carousel 1
Preheated air P is jetted from above and below 20. A heater 132 is provided in the preheating air injector 131, and the amount of heat generated by the heater 132 and the rotary conveyor 120.
With the speed of, a thermal gradient is created in the preheating unit 130. In addition, near the rotary conveyor 120, the temperature sensor 1
33 is provided, and the temperature control unit 181 of the controller 180 is based on the detection result of the temperature sensor 133.
Thus, the temperature of the heater 132 is controlled. The preheating unit 130 is covered with a heat insulating material 134.

The separation heating section 140 is means for injecting the hot jet J onto the printed circuit board to melt and blow off the solder of the printed circuit board to separate them. Separate heating unit 140
Is provided in the oblique portion of the carousel 120 continuously from the preheating unit 130, and the hot jet injector 141
The hot jet J is jetted to the printed circuit board in an oblique direction. This effectively separates the metal such as solder used in the details of the printed circuit board.

A heater 142 is provided in the hot jet injector 141, and a temperature sensor 14 is provided near the rotary conveyor 120.
3 are provided respectively, and the temperature control unit 18 of the controller 180 is based on the detection result of the temperature sensor 143.
1, the temperature of the heater 142 is controlled. Specifically, the heater 142 is controlled so that the temperature of the printed circuit board is at or above the melting point of eutectic solder or the like. The temperature of Hot Jet J is 100 at maximum.
It can be raised to about 0 ° C.

In the separation heating section 140, the parts blown off at the bottom are stagnant, so the separation discharge port 1
The temperature around 13 is also controlled. That is, the separation outlet 1
A temperature sensor 146 and a heater 147 are provided in the vicinity of 13, and the heater 147 is controlled based on the temperature detected by the temperature sensor 146. Further, the pressure of the hot jet J injected by the hot jet injector 141 is automatically controlled to a predetermined value. In this embodiment, it is 1 to 5 [Kg / cm ² ], but preferably 3 [Kg / cm ² ] or more. Further, the separation heating unit 140 is covered with the heat insulating material 144, and between the preheating unit 130,
The temperature partition plate 145 prevents the temperatures from being influenced by each other.

The cooling unit 150 separates and heats the separated heating unit 1 in order to safely and easily handle discharged matter such as a printed circuit board.
It is means for cooling the printed circuit board, which has been heated to a high temperature in 40, to about room temperature. The cooling unit 150 includes the carousel 1
The cooling air injector 151 is provided in the vicinity of the substrate discharge port 112, and the cooling air C is sprayed onto the rotary conveyor 120 from above and below.

The gas control system provided outside the printed circuit board processing system includes a gas regulator 161, a gas sensor 162, a gas combustor 163, and a dilution discharger 16.
Have 4. The gas regulator 161 supplies an inert gas into the heat insulating casing 110 in order to prevent combustible gas from being generated and burning or exploding by heating an electronic component. In this embodiment, nitrogen gas flows into the heat insulating casing 110 from the inert gas inlet 114. In addition, a gas pressure sensor (not shown) is provided in the heat insulating casing 110, and the controller 1 is based on the sensor output.
The gas control unit 182 of 80 controls the gas pressure in the heat insulating casing 110 to be a positive pressure. In this embodiment, the gas pressure inside the heat insulating casing 110 is controlled to be 1.1 to 1.5 atmospheres.

The gas sensor 162 and the gas combustor 16 are also provided.
3 and the dilution discharger 164 are provided so as to act on the gas discharged from the gas discharge port 115 of the heat insulating casing 110. The gas sensor 162 detects the concentration of combustible gas in the discharged gas. Then, when the concentration of the combustible gas is equal to or higher than the predetermined value, the gas combustor 163 burns it once. Further, when the concentration of the combustible gas is below a predetermined value, or when the gas etc. which has once been burned by the gas combustor 163, the external air is used by the dilution discharger 164 so that the concentration becomes finally lower. It is diluted and discharged. In the low temperature molten metal recovery apparatus 100 of the present embodiment, the exhaust gas is diluted so as to have a concentration of 3% or less and discharged. The gas sensor 162, the gas combustor 163, and the dilution discharger 164 are provided in the gas control unit 182 of the controller 180.
Controlled in.

Low temperature molten metal recovery apparatus 1 having such a configuration
A controller 180 is a control / operation unit that controls each unit of 00 and the entire apparatus. The controller 180 includes a temperature control unit 181, a gas control unit 182, a rotation control unit 183,
It also has an operation display / security control unit 184. As described above, the temperature control unit 181 controls the temperature of the preheating air P of the preheating unit 130, the temperature of the hot jet J of the separation heating unit 140, and the temperature in the vicinity of the separation discharge port 113 of the printed circuit board processing system. Control.

The gas control unit 182 controls the gas control system, that is, the gas regulator 161, the gas sensor 162, the gas combustor 163, the dilution discharger 164, etc., and the flow of the inert gas into the heat insulating casing 110, and Controls the discharge of gas after processing. The rotation control unit 183 controls the transport speed of the rotary conveyor 120 for transporting the printed circuit board. In the above-described printed board processing system, when the hot jet J having the same temperature is jetted onto the printed board, the heating state of the printed board is determined by the speed of the rotary conveyor 120. Therefore, the speed of the carousel 120 is controlled according to the heating conditions, the heat capacity of the substrates, the number of substrates to be loaded simultaneously, and the like.

The operation display / security control section 184 controls other overall control and control / display for safe operation.
Displays such as for easy operation. In particular,
It displays the movable state, the progressing process, the stopped state, and other auxiliary information such as conveyor speed, gas control state, combustible gas combustion state, and temperature. In addition, notification and status display of the case where the heat insulating casing 110 becomes abnormally high temperature, the case where the low temperature molten metal recovery device 100 is stopped by the emergency shutdown, and the like are also performed. The display panel 190 is a display unit for displaying such information.

Next, the low temperature molten metal recovery apparatus 1 of this embodiment
The operation of 00 will be described. First, the printed circuit board for separating and removing metal such as solder is the rotary conveyor 120.
Can be posted on. The rotary conveyor 120 is 10 to 100 [c
Controlled at a speed of [m / min]. The printed circuit board placed on the carousel 120 is loaded into the heat insulating casing 110 through the circuit board carry-in port 111, and first, the preliminary heating air P is jetted in the preliminary heating section 130 to be gradually heated. Since the inert gas is circulated in the heat insulating casing 110, the printed circuit board does not ignite due to this heating.

After passing through the preheating section 130, the rotary conveyor 120 is in a skewed state, and the separation heating section 140 separates and removes the solder. That is, the hot jet J of about 400 to 800 ° C. is applied to the printed circuit board in an amount of 1 to 5
It is injected with a pressure of [Kg / cm ² ], and low-temperature molten metal such as solder is melted and blown off. At this time, since the substrate is inclined, the hot jet J is relatively jetted to the holes in the substrate,
The parts and the solder can be effectively separated, and the fall of the liquefied solder or the like is promoted. The metal blown off from the substrate is discharged to the outside through the separation discharge port 113 and collected. The remaining printed circuit board is conveyed again by the leveled rotary conveyor 120, sufficiently cooled to about room temperature by the cooling unit 150, and discharged to the outside from the board discharge port 112.

Finally, the result of an experiment for collecting solder from the printed circuit board with the above-mentioned structure will be described. Using the low temperature molten metal recovery apparatus 100 of this example, the printed board was heated to a temperature of 400 ° C. by a hot jet J having a pressure of 1 [Kg / cm ² ] in a nitrogen gas circulation atmosphere, and an attempt was made to separate the solder. As a result, about 90% or more of lead, which is the main component of the solder used for the substrate, could be separated and recovered.

As described above, according to the low temperature molten metal recovery apparatus 100 of this embodiment, the printed circuit board is rotated by the rotary conveyor 12.
Just put on 0, it is possible to automatically separate and remove metal such as solder. This separation rate is very high,
Moreover, this process can be sequentially and continuously performed. In addition, the processing for this printed circuit board is completely insulated.
It is carried out in 10 and the discharged gas is appropriately treated. Therefore, a metal such as solder can be continuously separated with high efficiency, and a low-temperature molten metal recovery device that does not affect the human body can be provided.

The low temperature melt recovery apparatus of the present invention is not limited to this embodiment, and various modifications can be made. For example, the shape of the conveyance path of the printed circuit board, the direction of the jetted hot jet J, and the like may be any suitable shape and direction. In particular, when targeting a special printed circuit board used for a specific home electric appliance, the hot jet J
May be injected. Further, the temperature of the hot jet J, the heating temperature of the substrate, and the like may be arbitrarily changed according to the type of metal to be recovered, mounting conditions, and the like.
Further, although nitrogen is generally used as the inert gas in many cases, it is not limited to this, and any inert gas may be used. Further, the substance to be separated and removed is not limited to a metal such as solder containing lead as a main component, and any substance that melts at an equivalent temperature can be separated and removed.

[0034]

EFFECTS OF THE INVENTION By using the low temperature melt recovery apparatus of the present invention, it is possible to properly separate and remove metals such as lead from the wastes such as home electric appliances. That is, it is possible to recover a metal such as lead in a short time with a high recovery rate and without affecting the health of the worker. As a result, it is possible to bury waste such as home electric appliances in a safe state for disposal and prevent environmental pollution due to elution of metal such as lead from such waste. Further, since the waste can be obtained in such a safe state, for example, by crushing, compressing, and solidifying, it becomes possible to recycle it into a building material or the like. Furthermore, since metals such as lead are separated and recovered, these metals can also be recycled.

[Brief description of drawings]

FIG. 1 is a configuration diagram centering on a printed circuit board processing system in a low temperature molten metal recovery apparatus according to an embodiment of the present invention.

FIG. 2 is a configuration diagram centering on a control system in the low-temperature molten metal recovery apparatus of one embodiment of the present invention.

[Explanation of symbols]

Reference numeral 100 ... Low-temperature molten metal recovery device 101 ... Device housing 110 ... Insulating housing 111 ... Substrate carry-in port 112 ... Substrate discharge port 113 ... Separation discharge port 114 ... Inert gas introduction port 115 ... Gas discharge port 116 ... Air seal 117 ... Air seal 120 ... Rotary conveyor 121 ... Motor 130 ... Preliminary heating unit 131 ... Preliminary heating air injector 132 ... Heater 133 ... Temperature sensor 134 ... Insulation material 140 ... Separation heating unit 141 ... Hot jet injector 142 ... Heater 143 ... Temperature sensor 144 ... Heat insulating material 145 ... Temperature partition plate 146 ... Temperature sensor 147 ... Heater 150 ... Cooling part 151 ... Cooling air injector 161, Gas regulator 162 ... Gas sensor 163 ... Gas combustor 164 ... Diluting discharger 180 ... Controller 181 ... Temperature control part 182 ... Gas control unit 193 ... Rotation control unit 184 ... Operation Display / security control unit 190 ... Display panel

Front page continuation (72) Inventor Kinjiro Takayama 6-735 Kitashinagawa, Shinagawa-ku, Tokyo Within Sony Corporation (56) Reference JP-A-6-256863 (JP, A) JP-A-56-37699 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H05K 3/34 B23K 1/00

Claims (4)

(57) [Claims] 1. A casing having a printed circuit board carry-in port, a printed circuit board discharge port, an inert gas introduction port, an inert gas discharge port, and a melt discharge port, the printed circuit board carry-in port and the printed circuit board discharge port. A first flat portion connected to the printed circuit board carry-in port, a descending inclined portion whose lower end is located at the melt discharge port, and a second flat part connected to the printed circuit board discharge port. And a conveyance path in which a flat portion is continuously provided, and a conveyance path that conveys the printed circuit board, to which the low-temperature melt is admitted from the printed circuit board carry-in port, along the conveyance path to the printed circuit board discharge port. Means for preheating the printed circuit board by injecting a gas having a predetermined temperature at a predetermined pressure, and a high temperature gas provided in the vicinity of the descending slope portion. Predetermined Injected at a pressure, low temperature melt collecting device having a hot jet means for removing by melting a low-temperature melt adhered to the printed circuit board. 2. The low-temperature melt recovery apparatus according to claim 1, further comprising cooling means which is provided near the second flat portion and which lowers the printed circuit board to a predetermined temperature. 3. The hot jet means is 250 ° C. to 1
The low-temperature melt recovery apparatus according to claim 1 or 2, which injects a gas at about 000 ° C. 4. The low-temperature melt recovery apparatus according to claim 1, wherein the hot jet means injects a gas having a pressure of about 3 [Kg / cm ² ] or higher.