JPH05318528A - Apparatus and method for sealing injection-molded product - Google Patents

Abstract

PURPOSE:To obtain an apparatus characterized by that stage replacement is easy at the time of the replacement of a mold, a vacuum exhaust time is shortened, the reliability of a molded product or that of the apparatus itself is enhanced, piping work is easy and the number of piping parts is reduced. CONSTITUTION:Molds 1, 2 and piping 44 using a flexible hose are made automatically detachable by air cylinders 35, 37 and upper and lower valves 37, 43 are provided in the vicinity of the molds and a vacuum gauge 52 and an oil mist trap 55 are provided. These vacuum machineries are covered with a cover 57 and the exhaustion of the air in the cover 57 and the exhaustion of a vacuum pump 30 are simultaneously performed by a fan 56 to discharge air to a factory duct.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealing device and a sealing method for an injection molded product for sealing a semiconductor device with a resin.

[0002]

2. Description of the Related Art FIG. 4 is a cross-sectional view showing a conventional resin sealing device for a semiconductor device. In FIG.
The upper mold 1 and a pair of lower molds (hereinafter, referred to as an upper mold) 2
3) is an upper platen for mounting and fixing the upper mold 1,
Reference numeral 4 denotes a moving platen for mounting and fixing the lower mold 2, sliding in the vertical direction, and pressing and clamping the lower molds 1 and 2. Further, 5 is a lead frame (hereinafter referred to as a lead frame) on which a semiconductor element is mounted and electrically wired, 6 is a cylindrical resin tablet (hereinafter referred to as a tablet) which is a resin sealing material, and 7 is an upper mold 1 Upper cavity for forming a package, 8 is a lower cavity formed in the lower mold 2, 9 is a runner gate for supplying molten resin to the upper and lower cavities 7, 8, and 10 is a lower mold 2. A pot is provided for accommodating the tablet 6, a reference numeral 11 is a plunger for injecting and injecting a molten resin, and a reference numeral 12 is a Teflon ring provided on the plunger 11 for hermetically sealing the lower mold 2 and the plunger 11.

Further, 13 is an upper die ejector pin for releasing the upper package after sealing, 14 is an upper die ejector plate to which the upper die ejector pin 13 is attached, 15 is a spring A for operating the upper die ejector plate 14, 1
Reference numeral 6 is a lower die ejector pin for releasing the lower package after sealing, 17 is a lower die ejector plate for attaching the lower die ejector pin 16, and 18 is a spring B for operating the lower die ejector plate 17. Further, 19 is provided in the upper mold 1, an upper mold air vent for releasing air from the upper cavity 7 and preventing generation of voids at the time of molding, and 20 is provided in the lower mold 2 to remove air from the lower cavity 8. Lower mold air vent to prevent escape and generation of voids during molding,
Reference numeral 21 is a Teflon seal for preventing air leakage from the parting surfaces (contact surfaces) of the upper and lower molds 1 and 2, 22 is a seal A, 23 for preventing air leakage from the inside of the lower ejector.
Is a joint A attached to the upper mold 1, and 24 is an O-ring A for preventing air leakage from the connecting surface between the joint A23 and the upper mold 1.
Is. Further, 25 is a pipe A, 26 is a pipe B, 27 is a pipe C, and 28 is a pipe D, which are hermetically connected by a pipe clamp 29 including an O-ring and a clamper.
Reference numeral 30 is an oil rotary vacuum pump (hereinafter referred to as a vacuum pump) that evacuates the air in the mold, and 31 is ON / O for vacuum evacuation.
A vacuum valve for switching the FF, and 32 is an exhaust port of the vacuum pump 30.

Next, the operation will be described. First about 180
The lead frame 5 and the tablet 6 are placed on the lower mold 2 by a supply device (not shown) in a state where the upper mold 1 and the lower mold 2 which are heated and kept at a temperature of ℃ are opened. Then, the movable platen 4 is raised, and the upper die 1 and the lower die 2 are clamped and pressed. After the mold clamping is completed, the vacuum valve 31 is opened and the pipes D28, C2
Air in the upper and lower ejector chambers via B7, B26, A25, and the joint A23, and in the upper and lower cavities 7, 8, the runner gate 9, and the pot 10 via the upper and lower air vents 19 and 20 is in a high vacuum state. At this time, the Teflon seal 21, the seal A22, the Teflon ring 12, the O-ring A24, and the O-ring of the pipe connecting portion are kept airtight by preventing vacuum leakage. The air in the upper and lower molds 1 and 2 is exhausted by the exhaust port 32 of the vacuum pump 30 and, after being evacuated (exhausted) for a fixed time (here, 10 seconds), the plunger 11 is lifted and the melted tablet 6 is removed. The upper and lower cavities 7 and 8 are injected and injected through the runner gate 9 to perform package molding. Then, after curing for a fixed time (here, 60 seconds) to cure the molten resin, the vacuum valve 31 is shut off (closed), the injection of the molten resin by the plunger 11 is stopped, and the moving platen 4 descends (die). At the same time, the upper die ejector pin 13 is lowered to open the die and release the upper die package. The moving platen 4, that is, the lower die 2 continues to descend, and the lower die ejector plate 17 is pushed up by the pushing rod (not shown) at the lower end, so that the lower die ejector pin 16 rises and the lower die package is released. Done. After the mold opening and the mold releasing are completed, the discharge device (not shown) conveys the molded product from the lower mold 2, and one cycle is completed. Here, the vacuum pump 30 is in a state in which the vacuum pump 30 is constantly operating and continuously evacuated.

By the way, in Japanese Patent Laid-Open No. 62-273742, upper and lower molds are provided with communicating passages respectively, and vacuum is simultaneously drawn from each communicating passage before resin is injected into the cavity, and curing is completed. A transfer forming device is disclosed in which the mold is opened by sucking outside air into the cavity later. By using the device disclosed in the publication, the vacuum drawing time can be shortened and the mold can be opened smoothly.

[0006]

Since the conventional apparatus and method for sealing an injection-molded article are constructed as described above, there are many problems as described below. (1) When exchanging the mold, it is necessary to attach and detach the pipes, which increases the setup time. (2) Before injecting the molten resin into the cavity, the air in the pipe between the vacuum valve and the mold must be exhausted, and the evacuation time for vacuuming the mold is long. (3) It is impossible to determine the failure of the vacuum pump itself, and it is impossible to detect the occurrence of vacuum leakage from the seal part, etc., and there is a risk of producing defective products. (4) The hot air in the mold and oil smoke from the vacuum pump itself are exhausted directly into the room, which causes pollution in the clean room. (5) When the pump is stopped due to an abnormality during high vacuum, oil and oil smoke enter the mold via the piping system. (6) In order to prevent vacuum leakage from many pipe connections, O-rings and the like must be provided at each location, and the piping system is complicated and the piping work is complicated.

The present invention has been made to solve the above problems, and an object of the present invention is to provide an apparatus and a method for sealing an injection-molded article capable of achieving the following. .. (1) Reduce the setup time for die replacement. (2) Shorten the evacuation time until the inside of the mold is evacuated. (3) Detect the degree of vacuum of the vacuum pump itself. (4) It is possible to prevent oil smoke and high temperature air from being exhausted indoors from the vacuum pump. (5) It is possible to prevent backflow of oil or oil smoke when the operation is stopped due to an abnormal vacuum hoop. (6) The piping work is simple and the number of parts is reduced.

[0008]

A device for sealing an injection-molded article according to the present invention is provided with an automatic attachment / detachment mechanism at a connecting portion between a pipe and a mold. Further, an opening / closing valve for controlling the opening / closing state of the pipe tip is provided near the die. Further, a vacuum gauge for detecting the degree of vacuum of the vacuum pump is provided. Further, an oil mist trap is provided on the exhaust side of the vacuum pump. Further, the periphery of the vacuum pump is covered with a cover, and an exhaust fan is provided so that the air in the cover is forcibly exhausted to a duct together with the exhaust of the vacuum pump. Further, a main valve is provided between the vacuum pump and the piping, and an emergency leak valve is provided between the main valve and the vacuum pump.

Further, the method for sealing an injection-molded product according to the present invention is such that the inside of the pipe is evacuated before injection of the molten resin. Further, after the molten resin is injected and injected into the cavity, the driving ability of the vacuum pump is measured during the period when the cavity is not evacuated.

[0010]

According to the present invention, the connecting portion between the die and the pipe can be automatically attached / detached by moving it with an air cylinder or the like, and the setup time at the time of die exchange (product type change) can be shortened.
Further, by using the on-off valve provided in the vicinity of the mold to evacuate the inside of the pipe in advance before injecting the molten resin, the exhaust volume is reduced and the exhaust time is shortened.

Further, the degree of vacuum of the vacuum pump itself can be detected by the vacuum gauge provided on the side of the vacuum pump, and the abnormality of the vacuum pump and the vacuum leak from the mold and the piping system can be discriminated. Also, by providing the main valve and the emergency league valve on the vacuum pump side, the vacuum pump and the piping system are shut off in an emergency,
The pump side can be opened to the atmosphere, preventing backflow of oil and oil smoke into the piping and mold.

Further, since the cover is provided around the vacuum pump, the air inside the cover and the exhaust from the vacuum pump are forcibly exhausted to the factory duct by the fan. Further, by using a flexible hose for the piping system, the number of piping parts is reduced and the piping work is facilitated.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An injection molded product sealing apparatus according to an embodiment of the present invention will be described below with reference to FIG. The same reference numerals as those in FIG. 4 denote the same or corresponding parts, 33 is a joint B slidable in the upper platen 3, 34 is provided in the upper mold 1, and a joint B33.
O-rings B and 35 that are pressed and sealed by the upper platen 3
Is an upper air cylinder fixed to the connection plate A
36 is connected to the joint B33. Reference numeral 37 denotes a non-excitation closed type upper exhaust vacuum valve (hereinafter referred to as an upper valve) which is airtightly connected to the joint B33 by a pipe clamp 29.

Further, 38 is a lower die exhaust port which is hermetically fixed to the lower die 2, 39 is a joint C, 4 which is slidable in the movable platen 4.
Reference numeral 0 denotes an O-ring C provided at the joint C39, and an O-ring C for pressure-sealing the lower die exhaust port 38, 41 denotes a lower air cylinder fixed to the movable platen 4, and is connected to the joint C39 by a connection plate B42. Reference numeral 43 denotes a non-excitation closed type lower die exhaust vacuum valve (hereinafter referred to as lower die valve) which is airtightly connected to the joint C39 by the pipe clamp 29.

Further, 44 is a flexible hose A whose one end is connected to the upper mold valve 37 via the pipe clamp 29, and the other end is connected to a joint D45 which is connected to the lower mold valve 43 via the pipe clamp 29. , 46 are flexible hoses B connecting the joint D45 and the filter A47.

Further, 48 is a non-excitation closed type main vacuum valve (hereinafter referred to as a main valve) provided in the latter stage of the filter A 47, and 49 is a non-excitation opening provided between the filter A 47 and the main vacuum valve 48. Type league valve, 50 is a non-excitation open type emergency leak valve provided in the latter stage of the main vacuum valve 48, and 51 and 52 are vacuum meters provided in the preceding stages of the league valve 49 and the emergency leak valve 50, respectively. Main gauge and check gauge. Further, a vacuum hoop 30 is provided at a stage subsequent to the emergency leak valve 50 via a mechanical booster pump 53,
The pumping speed of the vacuum pump 30 is enhanced by a mechanical booster pump 53. 54 is a vacuum pump 3
It is a filter B provided at the intake port of 0. Further, 55 is an oil mistrap for removing the oil discharged from the exhaust port of the vacuum pump 30, and 56 is a fan.
The component 6 is covered with a cover 57 that covers the peripheral equipment of the vacuum pump 30. Here, it is assumed that the devices after the drawing number 46 are indicated by wiring symbols.

Next, the operation will be described. In FIG. 2, the vacuum pump 30 and the mechanical booster pump 54 are constantly operating as in the conventional case at the timing T0 which is the cycle start point, the main valve 48 is opened, and the leak valve 49 and the emergency leak valve 50 are closed. In addition, the upper and lower mold valves 37 and 43 are closed. Therefore, in this state, the pump 30
To the upper and lower mold valves 37, 43, that is, the piping portions (44, 45, 46) are in a high vacuum state. In the above state, the lead frame 5 and the tablet 6 are placed on the lower mold 2 as in the conventional device.

Then, the movable platen 4 rises, the upper and lower molds 1 and 2 start contacting each other, and when the pressing force exceeds 3 tons (pressing force detecting means is not shown) (timing T1),
It is determined that the lower mold is in contact with the upper mold valve 37 and the lower mold valve 4.
Open 3. When the upper and lower valves 37 and 43 are opened, the inside of the upper die 1 is through the joint B33, and the inside of the lower die 2 is the joint C.
39 and the lower die exhaust port 38 are evacuated.

When the degree of vacuum measured by the main gauge 51 becomes 1 Torr or less (timing T3), it is determined that the inside of the mold has an allowable degree of vacuum (molding condition), and sufficient pressure at timing T2 (here Then 80 tons)
After the confirmation, the plunger 11 rises, the tablet 6 is injected into the upper and lower cavities 7 and 8 through the runner gate 9, and the lead frame 5 is resin-sealed. Here, when the vacuum evacuation time t in the mold (the period from timing T1 to timing T3) exceeds a certain time (here, 5 seconds), the allowable preheating time (tablet 6 which is a thermosetting resin is melted, It shows the time until it hardens further and cannot be molded.
Continue evacuation until 0 seconds), and by that time 1To
If it becomes rr or less, the cycle is continued, and thereafter, it is considered that there is some abnormality and an alarm is issued. On the other hand, when the evacuation time t exceeds the permissible preheat time (20 seconds), the cycle is stopped and an alarm is issued because molding is not possible and the vacuum system is abnormal.

After the injection is completed (timing T4), a cure timer (60 seconds) is started to cure the molten resin, and at the same time, a timer (not shown) is activated to set T time (20 (seconds) <T <60.
(Seconds)) Elapsed (timing T5), the injection has already been completed and the vacuuming is no longer necessary, so the main valve 4
After closing 8, the leak valve 49 is opened to break the high vacuum state in the molds 1 and 2 and each of the pipes 44 and 46 before opening the mold to introduce the atmosphere.

760 Tor in the molds 1 and 2 and each pipe
After the main gauge 51 detects that r, that is, atmospheric pressure (timing T6), the upper and lower valves 37 and 43 are closed, the leak valve 49 is then closed, the main valve 48 is opened, and the pump is pumped again. The piping portion from 53, 30 to the upper and lower valves 37, 43 is put in a high vacuum state to prepare for vacuum drawing in the mold in the next cycle.

While the main valve 48 is closed,
Check gauge 52 detects the degree of vacuum and pumps 53, 3
The ability of 0 (here, 0.001 Torr or less) is checked, and if it is abnormal (exceeds 0.001 Torr), an alarm is issued. When the curing is completed, the mold is opened, the molded product is taken out, one cycle is completed, and the next cycle is repeated.

By the way, if any abnormality occurs during the cycle operation and the power is turned off, the main valve 48 is immediately closed, the league valve 49 is opened, the emergency leak valve 50 is opened, and the upper and lower valves are opened as shown in FIG. 37 and 43 are closed. At this time, the power supplies of the pumps 53 and 30 are also turned off and the operation is naturally stopped. By this operation, the pumps 53, 30
And the piping system and the mold are melted to open the sides of the pumps 53 and 30 to the atmosphere to prevent the backflow of oil and oil smoke from the pumps 53 and 54 to the piping and the mold.

Further, the oil mistrap 55 provided on the exhaust side of the vacuum pump 30 prevents the oil smoke discharged from the vacuum pump 30 from being discharged to the outside, and these vacuum devices are covered by a cover 57. Therefore, the dust and oil smoke emitted from the pumps 30, 53 are prevented from being emitted to the outside, and the fan 56 provided in the cover 57 compulsorily discharges them together with the exhaust to the factory duct.

Further, the resin burr generated in the mold tends to be carried to the pumps 30, 53 side through the piping system, but it is provided at the filter A47 provided in the piping path and the intake port of the vacuum pump 30. It is removed by the filter B54 to prevent it from entering the vacuum pump 30.

Further, the upper mold 1 and the lower mold 2 for changing the type of product.
When exchanging with, the upper die air cylinder 35 always at the lower end is raised by pressing a die exchange switch (not shown), and the lower air cylinder 41 always at the upper end is lowered to move up and down. The molds 1 and 2 and the piping system are automatically separated at the joint B33 and the joint C39. Then, after the mold is replaced (not shown), the upper mold air cylinder 35 is lowered by pressing the switch again, and the connection plate A36 and the joint B are connected.
The upper mold 1 is connected to the pipe through 33, and the lower mold air cylinder 41 is raised to connect the connecting plate B42 and the joint C39.
The lower mold 2 and the pipe are connected via. At this time, the connecting surface between the upper mold 1 and the joint B33 is the O-ring B34, and the lower mold 2
The connection surface between the (lower die exhaust port 38) and the joint C39 is hermetically sealed with an O-ring C40, and the upper and lower air cylinders 35 and 41 constantly apply air pressure to the joint B33 and the joint C39 to provide O-rings B34 and C40. The vacuum leak is prevented by pressing.

As described above, according to this embodiment, the upper and lower molds 1 and 2 and the flexible hose 44 are connected to the air cylinder 3.
Since it can be moved by 5, 41 and automatically detached, the setup time at the time of die replacement can be shortened. Also, upper and lower molds 1, 2
Between the vacuum hose 44 and the flexible hose 44
3 is provided so that the inside of the pipe is evacuated before injection and injection, the exhaust volume is reduced and the exhaust time is shortened. Further, since the vacuum degree of the pumps 53 and 54 is checked by the check gauge 52 when the main valve 48 is closed, the capacity of the pump itself can be measured. Further, even if the power is cut off for some reason, the main valve 48 is closed and the emergency leak valve 50 is opened, so that the vacuum pump 30 and the piping system (46, 44) are opened.
Etc.), and the pump 30 side can be opened to the atmosphere, so that backflow of oil and oil smoke into the piping system and the molds 1 and 2 is prevented.

Further, since the periphery of the vacuum pump 30 is covered with the cover 57 and the exhaust from the cover 57 and the vacuum pump 30 is forcibly exhausted to the factory duct by the fan 56, the inside of the clean room due to oil smoke and high temperature air It is possible to prevent pollution. Further, by using the flexible hoses 44 and 46 in the piping system, the number of piping parts can be reduced and the piping work can be facilitated.

In the above embodiment, the oil rotary vacuum pump 3 is used.
No. 0 and a mechanical vacuum booster pump 53 are used to evacuate, but other vacuum exhaust devices such as a turbo molecular pump or a scroll hoop may be used. Further, although the air cylinder is used for the automatic attachment / detachment mechanism of the mold and the pipe portion in the above-mentioned embodiment, a motor or other actuator may be used and the same effect as that in the above-mentioned embodiment is obtained.

In the above embodiment, the joint B is formed between the mold and the mold.
Although the upper and lower valves 37 and 43 are provided via 33 and C39, the upper and lower valves may be directly connected to the molds 1 and 2 or may be connected via other parts. Further, in the above embodiment, the vacuum valves 37 and 43 are provided on the upper and lower molds 1 and 2, respectively.
However, the vacuum valve may be provided in either one of the molds, and the same effect as that of the above embodiment can be obtained.

Further, in the above embodiment, the O-ring is used to seal the joint between each mold and the pipe, but a rubber packing or other sealing material may be used.
Alternatively, a sealant may not be used (in this case, the hermeticity will be lowered), and the same effect as that of the above-described embodiment can be obtained.

[0032]

As described above, according to the present invention, since the mold and the piping system are automatically attached and detached, the setup time at the time of exchanging the mold is significantly shortened, and the mold is kept near the mold. An on-off valve was installed to control the open / closed state of the pipe tip, and the inside of the pipe was evacuated before injection of molten resin, so the exhaust volume was reduced and the exhaust time was shortened. It has a good effect.

Further, a vacuum gauge is provided to measure the performance of the vacuum pump, a filter is provided to trap the oil mist, and the vacuum pump side is shut off from the piping side when the atmosphere is opened to the atmosphere in an emergency. Therefore, there is an effect that the reliability of the device can be improved.

[Brief description of drawings]

FIG. 1 is a front sectional view showing a sealing device for an injection-molded article according to an embodiment of the present invention.

FIG. 2 is an operation timing chart of a main part of the sealing device.

FIG. 3 is a timing chart of a valve opening / closing timing of the sealing device in an emergency.

FIG. 4 is a front sectional view showing a conventional sealing device for injection molded products.

[Explanation of symbols]

 1 Upper Die 2 Lower Die 3 Upper Platen 4 Moving Platen 5 Lead Frame 6 Tablet 7 Upper Cavity 8 Lower Cavity 9 Runner Gate 10 Pot 11 Plunger 12 Teflon Ring 13 Upper Die Ejector Pin 14 Upper Die Ejector Plate 15 Spring A 16 Lower Die Ejector pin 17 Lower ejector plate 18 Spring B 19 Upper air vent 20 Lower air vent 21 Teflon seal 22 Seal A 23 Joint A 24 O-ring A 25 Piping A 26 Piping B 27 Piping C 28 Piping D 29 Piping clamp 30 Vacuum pump 31 Vacuum valve 32 Exhaust port 33 Joint B 35 Upper air cylinder 36 Connection plate A 37 Upper mold valve 38 Lower mold exhaust port 39 Joint C 40 O-ring C 41 Lower mold air cylinder 42 Connection plate B 43 Lower mold valve 44 F Flexible hose A 45 Joint D 46 Flexible hose B 47 Filter A 48 Main valve 49 Leak valve 50 Emergency leak valve 51 Main gauge 52 Check gauge 53 Mechanical booster pump 54 Filter B 55 Oil mistrap 56 Fan 57 Cover

Claims (10)

[Claims] 1. A pair of upper and lower molds having a cavity for accommodating an article to be molded, and a vacuum pump for vacuuming the inside of the cavity, wherein a molten resin is injected and injected into the cavity in a vacuum state to form the object to be molded. In an injection-molded product sealing device for sealing a product with a resin, a pipe for connecting an exhaust port formed in each of the pair of molds to the vacuum pump, and the attachment / detachment of the pipe to / from the mold are automatically performed. An apparatus for sealing an injection-molded product, comprising: 2. The device for sealing an injection molded product according to claim 1, wherein a flexible hose is used for the pipe. 3. A pair of upper and lower molds having a cavity for accommodating an article to be molded, and a vacuum pump for vacuuming the inside of the cavity, wherein a molten resin is injected and injected into the cavity in a vacuum state to form the object to be molded. In an injection-molded product sealing device for sealing a product with a resin, a pipe connecting an exhaust port formed in each of the pair of molds and the vacuum pump, and a connection between the pipe and an exhaust port of the mold. And an opening / closing valve for controlling the open / closed state of the pipe tip, the apparatus for sealing an injection-molded product. 4. A pair of upper and lower molds having a cavity for accommodating an article to be molded, and a vacuum pump for evacuating the inside of the cavity, wherein a molten resin is injected and injected into the cavity in a vacuum state to form the object to be molded. An injection-molded product sealing device for sealing a product with a resin, wherein an oil mist trap is provided on the exhaust side of the vacuum pump. 5. A pair of upper and lower molds having a cavity for accommodating an article to be molded, and a vacuum pump for vacuuming the inside of the cavity are provided, and the molten resin is injected and injected into the cavity in a vacuum state to form the object to be molded. In an injection molding product sealing device for sealing products with a resin, a structure is provided in which the periphery of the vacuum pump is covered with a cover, an exhaust fan is provided, and the air in the cover is forcibly discharged to a duct together with the exhaust of the vacuum pump. An apparatus for sealing an injection-molded product characterized by the above. 6. A pair of upper and lower molds having a cavity for accommodating an article to be molded, and a vacuum pump for vacuuming the inside of the cavity, wherein a molten resin is injected and injected into the cavity in a vacuum state to form the object to be molded. An injection-molded product sealing device for sealing a product with a resin, comprising a vacuum gauge for detecting the degree of vacuum of the vacuum pump. 7. A cavity in a vacuum state, comprising: a pair of upper and lower molds having a cavity for accommodating a molding target; and a vacuum pump connected to the molds through a pipe for vacuuming the inside of the cavity. A main valve provided between the vacuum pump and a pipe, comprising: a main valve provided between the vacuum pump and a pipe; And an emergency leak valve provided between the two. 8. After clamping a pair of upper and lower molds, a molten resin is injected and injected into a cavity inside the vacuumed mold to seal a molded product, and then the mold is opened. In the method of sealing an injection-molded product that takes out a resin-sealed injection-molded product, the inside of the pipe is evacuated in advance before the injection of the molten resin. Sealing method. 9. After clamping a pair of upper and lower molds, a molten resin is injected and injected into a cavity inside the vacuumed mold to seal the molded product with a resin, and then the mold is opened. In the method for sealing an injection-molded product that takes out a resin-sealed injection-molded product, the driving capability of the vacuum pump during the period when the cavity is not evacuated after the molten resin is injected and injected into the cavity. A method of encapsulating an injection-molded product, the method including measuring a value of 10. After clamping a pair of upper and lower molds, a molten resin is injected and injected into a cavity inside the vacuumed mold to seal the molded product, and then the mold is opened. In a method for sealing an injection molded product, in which a resin-sealed injection molded product is taken out, when the abnormality of the vacuum pump occurs, the vacuum pump is opened to the atmosphere and the connection between the vacuum pump and the pipe is cut off. A method for sealing an injection molded product.