JPH11170351A - Production of resin tank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a method for producing a resin tank which can form the seal surface of a through hole in high roughness and can manufacture it without need for complex processing at low costs. SOLUTION: In a mold 30, a cylindrical projection 35 projected inside is formed and a tool 38 with a blade is arranged. When a parison is expanded in the mold 30, the parison contacts the peripheral wall of the projection 35, and the inside wall surface of a through hole 12 is to be molded by the peripheral wall of the projection 35 to form a hollow body T. After that, the tool 38 is advanced to cut off a cut-off piece, and a washer tank is formed. the inside wall surface of the through hole 12 is not cut surface, since the through hole 12 is formed along the peripheral wall of the projection 35, the roughness of the inside wall surface can be made high. Besides, since it can be made by one blow molding process, man-hours is reduced to curtail costs.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a resin tank having a through hole in a side wall, and more particularly to a method of manufacturing a resin tank to which hollow molding (blow molding) is applied.

[0002]

2. Description of the Related Art As a resin tank manufactured by blow molding (blow molding), for example, a washer tank applied to a wiper device of a vehicle and containing a liquid such as a window washer liquid is known.

In this type of washer tank, as shown in FIG. 25, a water supply through-hole 82 is formed in a side wall portion of the tank 80. Generally, in the vicinity of the through hole 82,
The water supply pump 84 is attached to the tank 80 itself. The pump 84 has an inlet 86 whose grommet 8
8, it is fitted into the through hole 82, thereby ensuring the sealing performance around the through hole 82. When the pump 84 operates, the washer fluid in the tank 80 is absorbed by the pump 84 and discharged from the outlet 90.

By the way, as described above, the through hole 8 of the tank 80 is used.
In FIG. 2, a grommet 88 is interposed between the inlet 86 of the pump 84 and the grommet 88, so that the sealing performance of the through hole 82 is ensured. Is the inner peripheral wall of the through hole 82 (that is,
A high surface roughness is required for the contact surface with the grommet 88). In other words, if the surface roughness of the inner peripheral wall of the through hole 82 is poor,
Adhesion with the grommet 88 deteriorates, resulting in poor sealing.

For this reason, conventionally, after forming the main body portion (hollow body) of the tank 80 by hollow molding, it is processed by a tool such as a drill to form the through-hole 82 and to seal the sealing surface (in the through-hole). The surface roughness of the peripheral wall is secured. Therefore, the number of manufacturing steps is large and it takes time and effort to manufacture, which is a cause of high cost.

In this case, a manufacturing technique has been proposed which does not require post-processing using a tool such as a drill and can form the through-holes 82 when the tank 80 is formed by hollow molding (Japanese Patent Publication No. Hei 3 (1994)). -76808).

According to the manufacturing technique disclosed in the above-mentioned publication, a tool with a blade constituting a cavity is provided so as to enter outside the mold surface (cavity) of a molding die, and the parison is expanded to expand the hollow body. Is formed, the side wall portion of the hollow body is cut off (drilled) by the tool with a blade to form the through hole 82. According to this manufacturing technique, post-processing using a tool such as a drill is not required after the tank 80 (hollow body) is formed by hollow molding,
The tank 80 can be formed in one manufacturing process.

However, in the manufacturing technique disclosed in the above-mentioned publication, since the through-hole 82 is formed by cutting (piercing) the side wall portion of the hollow body with a bladed tool, the inner peripheral wall of the through-hole 82 is formed. The portion (seal surface) is a cut surface. Therefore, there is a disadvantage that the roughness of the inner peripheral wall portion (seal surface) is poor (necessary surface roughness cannot be secured), and as a result, poor sealing tends to occur. Therefore, the tank 80 manufactured by the manufacturing technique disclosed in the above publication cannot be applied to a washer tank of a vehicle or the like.

[0009]

SUMMARY OF THE INVENTION In consideration of the above-mentioned facts, the present invention can form a sealing surface of a through hole with a high surface roughness and at a low cost without requiring complicated processing. It is an object to obtain a method of manufacturing a resin tank that can be realized.

[0010]

According to a first aspect of the present invention, there is provided a method of manufacturing a resin tank having a through hole in a side wall portion. Is provided in the mold in advance by protruding into the mold more than the mold surface of the mold, and a tool with a blade configured in a columnar shape and having a cutting edge at the tip is formed by the cylindrical protrusion. The resin parison is arranged in the mold, the resin parison is expanded in the mold, the resin parison is pressed against the mold, and the resin parison is brought into close contact with the peripheral wall of the convex portion. A hollow body is formed in a state where the inner peripheral wall surface of the through hole is formed, and then the bladed tool is advanced inward of the hollow body, and the resin of the hollow body corresponding to the cutting edge of the bladed tool is formed. Cut the parison to form the through holes, , The bladed tool with disengaging from said hollow body, open the mold is taken out a hollow body in which the through hole is formed, it is characterized in that.

[0011] In the method for manufacturing a resin tank according to the first aspect of the invention, the convex portion having a cylindrical shape corresponding to the through hole of the tank protrudes in a state in which the convex portion enters the inside from the mold surface of the mold. It is provided in the mold. Further, a tool with a blade is disposed in the cylindrical convex portion.

By expanding the resin parison in the molding die, the parison is pressed by the molding die and adheres to the peripheral wall of the projection. Thus, the hollow body is formed in a state where the inner peripheral wall surface of the through hole is formed by the peripheral wall of the convex portion.

Next, when the bladed tool disposed in the projection is advanced toward the inside of the hollow body, the resin parison of the hollow body corresponding to the cutting edge of the bladed tool is cut off to form a through hole. Further, the resin-made tank is manufactured by removing the bladed tool from the hollow body, opening the mold, and taking out the hollow body having the through-hole formed therein.

According to the first aspect of the present invention, the resin parison expands in the mold and the resin parison adheres to the peripheral wall of the projection, thereby forming a through hole. You. That is, since the inner peripheral wall surface of the through hole is formed not according to the cut surface but following the peripheral wall of the cylindrical convex portion (since the peripheral wall of the convex portion becomes the inner peripheral wall surface of the through hole as it is), The roughness of the inner peripheral wall portion (seal surface) can be increased (the required surface roughness can be secured). Therefore, the sealing property of the through hole can be ensured, and it can be suitably used for, for example, a washer tank of a vehicle.

In addition, the through-hole can be formed at the same time when the hollow body is formed by hollow molding, instead of the conventional configuration in which the through-hole is formed by post-processing using a tool such as a drill. The provided resin tank can be formed in a single manufacturing process, and the cost can be reduced.

As described above, in the method for manufacturing a resin tank according to the first aspect, the sealing surface of the through-hole can be formed with a high surface roughness, and the sealing surface can be formed without requiring complicated processing. It can be realized by cost.

According to a second aspect of the present invention, there is provided the resin tank manufacturing method according to the first aspect, wherein a heater is provided at a cutting edge portion of the bladed tool, and the cutting edge is provided by the bladed tool. When the resin parison of the hollow body corresponding to the above is cut off, the resin parison is cut while being melted by the heater.

In the method for manufacturing a resin tank according to the second aspect, when the resin parison of the hollow body corresponding to the cutting edge is cut off by the bladed tool, the resin parison is heated and melted by the heater provided at the cutting edge portion. While being resected.

Therefore, it is not necessary to apply a large pressing force to the cut portion of the resin parison when the tool with a blade is advanced toward the inside of the hollow body to cut the resin parison of the hollow body to form a through hole. . Therefore, the hollow body (a general part of the resin parison) does not unnecessarily shift or move with the movement of the bladed tool, and the resin parison corresponding to the through hole can be reliably cut off. Therefore, the product accuracy is further improved. For this reason, even in a place where the holding power of the hollow body (a general part of the resin parison) by the molding die is low, the through-hole can be easily formed (in other words, regardless of the formation position of the through-hole). , The mold can be set), and the degree of freedom of design and the range of application can be expanded.

According to a third aspect of the present invention, in the method for manufacturing a resin tank according to the first aspect, the resin parison of the hollow body corresponding to the cutting edge is cut by the bladed tool. At this time, the cutting piece is held by the tool with a blade, and when the tool with the blade is detached from the hollow body, the cutting piece is removed from the hollow body together with the tool with the blade. .

In the method for manufacturing a resin tank according to the third aspect, when the resin parison of the hollow body corresponding to the cutting edge is cut by the cutting tool, the cut piece is held by the cutting tool, and further, the cutting piece is held by the cutting tool. When the tool is detached from the hollow body, the cutting piece together with the bladed tool is removed from the hollow body.

Therefore, the cut piece of the resin parison does not fall into the hollow body and remains, so that the step of opening the mold and taking out the hollow body and then taking out the remaining cut piece again becomes unnecessary. In addition, the number of steps can be reduced and the cost can be reduced.

According to a fourth aspect of the present invention, in the method for manufacturing a resin tank according to the first, second or third aspect, the convex portion is formed by splitting a pair of male and female parts. The through hole is formed by providing the through hole at a position near a mold matching portion of a mold.

In the method for manufacturing a resin tank according to the fourth aspect, the convex portion (ie, a tool with a blade) is provided in the vicinity of the mating portion of the pair of male and female split molds, and the through hole is formed. You.

Here, a resin parison (a part other than a part formed as a product in a resin tank) is photographed and held at the mold matching part of the split mold. Therefore, when the bladed tool disposed in the projection is advanced toward the inside of the hollow body to cut the resin parison of the hollow body to form a through hole, the hollow body (resin) is moved with the movement of the bladed tool. General part of the parison) does not shift or move unnecessarily,
The resin parison corresponding to the through hole can be reliably removed. Therefore, the product accuracy is further improved.

According to a fifth aspect of the present invention, there is provided a resin tank manufacturing method according to any one of the first to fourth aspects, wherein the undercut portion is formed in the hollow body. The present invention is characterized in that a cavity of the mold is formed, and the convex portion is provided near a position of the mold corresponding to the undercut portion to mold the through hole.

In the method for manufacturing a resin tank according to the fifth aspect, the cavity of the mold is formed so as to form an undercut portion in the hollow body, and the vicinity of the mold corresponding to the undercut portion of the hollow body. A cylindrical portion (that is, a tool with a blade) is provided at the position, and a through hole is formed.

Here, the undercut portion of the hollow body is naturally difficult to separate from the mold, in other words, the hollow body is securely held by the mold. Therefore, when the bladed tool disposed in the projection is advanced toward the inside of the hollow body to cut the resin parison of the hollow body to form a through hole, the hollow body (resin) is moved with the movement of the bladed tool. The resin parison corresponding to the through hole can be reliably cut off without unnecessarily shifting or moving the parison (general part of the parison). For this reason,
Product accuracy is further improved.

[0029]

FIG. 5 shows the structure of a main part of a washer tank 10 as a resin tank manufactured by applying the method for manufacturing a resin tank according to the first embodiment of the present invention. This is shown in a front view. FIG. 6 is a bottom view showing a configuration of a main part of the washer tank 10.

The washer tank 10 is applied to, for example, a wiper device of a vehicle, and can store a liquid such as a window washer liquid.

In the side wall of the washer tank 10, a water supply through hole 12 is formed. Further, a pair of pump fitting portions 14 facing each other are formed in a side wall portion near the through hole 12. As will be described later in detail, the pump fitting portion 14 is an undercut portion when the washer tank 10 is manufactured by blow molding. A water supply pump 16 is fitted and attached to the pump fitting portion 14. The pump 16 has an inlet 18 fitted into the through-hole 12 through the grommet 20, thereby ensuring the sealing around the through-hole 12. When the pump 16 operates, the washer tank 10
In this configuration, the washer fluid inside is absorbed by the pump 16 and discharged from the outlet 22.

Here, FIG. 1 is a sectional view showing main steps of a method for manufacturing a resin tank according to the first embodiment of the present invention.

This manufacturing method is basically hollow molding (blow molding), and can manufacture the above-mentioned washer tank 10, and uses a pair of male and female split molds 30 and 32. A cavity 34 corresponding to the washer tank 10 (product) is formed by the pair of split molds 30 and 32.

Further, one of the molding dies 30 has a projection 35 and a tool hole 36 formed therein. The convex portion 35 is formed in a cylindrical shape corresponding to the through hole 12 of the washer tank 10 described above, and is provided so as to protrude more than the general mold surface of the molding die 30. Further, a tool hole 36 is formed inside the convex portion 35 (to be continuous with the inner space of the convex portion 35).

Further, a cavity 34 is formed in the molding die 30 near the tool hole 36 for molding the pump fitting portion 14 (undercut portion).

Further, a tool 38 with a blade is provided in the tool hole 36.
Is arranged. The tool 38 with a blade is formed in a columnar shape, and further has a blade edge portion 40 at the tip as shown in detail in FIGS. 2 and 3. Therefore, the bladed tool 38
Corresponds to the through-hole 12 of the washer tank 10 described above.

Further, a cylinder 44 is fixed to the mold 30 via a fixing table 42. Cylinder 44
The rod 46 is connected to the rear side of the bladed tool 38 so that the rod 46 expands and contracts by the operation of the cylinder 44 so that the bladed tool 38 can be moved in the tool hole 36.

Here, when the washer tank is formed, the bladed tool 38 is used to form the tip surface of the projection 35 (the cavity 3).
4) projecting into the state more inside (or
(So that they are flush).

Next, FIG. 4 is a flowchart showing the specific steps of the method for manufacturing the resin tank according to the first embodiment, and the specific steps of the present method are described in accordance with the flowchart. explain.

As described above, when the washer tank 10 is formed, the mold 30 provided with the projection 35 and the mold 32 are set, and the bladed tool 38 is inserted into the inside of the tip of the projection 35. It is provided in advance in a protruding state.

After setting the split molds 30, 32 and the bladed tool 38 in this way, first, in step 100, a resin parison is injected. Further, in step 102, the injected resin parison is sagged and stretched by its own weight. The temperature of the resin parison in this step is, for example, 185 degrees.

Next, in step 104, the resin parison is clamped by the split molds 30 and 32.
In step 106, compressed air is blown (air blown) into the resin parison while the clamping pressure by the split molds 30 and 32 is maintained. The air blow time is, for example, 35 seconds.

As a result, the resin parison expands in the cavities 34 of the split molds 30 and 32, and as shown in FIGS. 1 and 2, the resin parison presses the mold surfaces (cavities 34) of the split molds 30 and 32. At the same time, it is brought into close contact with the peripheral wall of the projection 35.

Thus, the hollow body T is formed in a state where the inner peripheral wall surface of the through hole 12 is formed by the peripheral wall of the convex portion 35.

Next, in step 108, the cylinder 44 is operated to advance the bladed tool 38 toward the inside of the hollow body T (the split molds 30, 32). Thereby, as shown in FIG. 3, the resin parison of the hollow body T corresponding to the cutting edge portion 40 of the bladed tool 38 is cut off, and the through hole 12 is formed. At this point, the hollow body T (resin parison)
Is, for example, 120 degrees.

After the resin parison of the hollow body T has been cut off to form the through-holes 12, in step 110, the bladed tool 38 is held in its moving state (for example, 1).
0 seconds). In this state, the hollow body T and the cut piece S are cooled to about 90 degrees.

Further, in step 112, the cylinder 44 is operated again, and the bladed tool 38 is moved backward in the opposite direction to the above-mentioned direction so as to be separated from the hollow body T (split molds 30, 32). At this time, the cut piece S may fall into the hollow body T, but the cut piece S does not adhere to the inside of the hollow body T because it has already been cooled in step 110.

Thereafter, in step 114, the air in the split molds 30 and 32 is evacuated and exhausted.
At 6, the split molds 30 and 32 are opened. Further, in step 118, the washer tank 10 made of resin is manufactured by taking out the hollow body T in which the through-hole 12 is formed. At this point, the washer tank 10
Is 88 degrees, for example. When the cut pieces S fall into the hollow body T, a step of taking out the cut pieces S remaining inside the hollow body T is performed after the step 118.

Here, according to the method of manufacturing a resin tank according to the first embodiment, the resin parison expands in the split molds 30 and 32 so that the resin parison adheres to the peripheral wall of the projection 35. By doing so, the through hole 1 of the washer tank 10
2 are formed. That is, since the inner peripheral wall surface of the through hole 12 is formed not according to the cut surface but following the peripheral wall of the convex portion 35 (since the peripheral wall of the convex portion 35 becomes the inner peripheral wall surface of the through hole 12 as it is), The roughness of the inner peripheral wall portion (seal surface) can be increased (the required surface roughness can be ensured). Therefore, the sealing property of the through hole 12 can be ensured, and it is most suitable as a vehicle washer tank.

Further, instead of the conventional structure in which the through holes 12 are formed by post-processing using a tool such as a drill, the through holes 12 are simultaneously formed when the hollow body T is formed by blow molding.
Can be formed, and the washer tank 10 having the through-hole 12 can be formed in a single manufacturing process, so that the cost can be reduced.

Further, in the method for manufacturing a resin tank according to the first embodiment, as shown in FIG. 7, the mold surface (cavity 34) of the molding die 30 is fitted to the hollow body T by the pump fitting portion 1.
4 (undercut)
Mold 30 corresponding to pump fitting portion 14 of hollow body T
Is provided with a protruding portion 35 (a tool 38 with a blade) in the vicinity of the shape of the through hole 12.

Here, as shown in FIG. 8, the pump fitting portion 14 (undercut portion) of the hollow body T is of course
The hollow body T is hard to be separated from 0, in other words, the hollow body T is securely held by the mold 30. Therefore, the aforementioned step 1
At 08, when the bladed tool 38 is advanced toward the inside of the hollow body T to cut the resin parison of the hollow body T to form the through hole 12, the hollow body T (the resin The resin parison corresponding to the through hole 12 can be reliably cut off without unnecessarily shifting or moving the parison (a general part of the parison). For this reason, the product accuracy of the washer tank 10 is further improved.

As described above, in the method for manufacturing the resin tank according to the first embodiment, the sealing surface of the through hole 12 of the washer tank 10 can be formed with a high surface roughness.
In addition, this can be realized at low cost without requiring complicated processing.

Next, another embodiment of the present invention will be described. Note that components and manufacturing steps that are basically the same as those in the first embodiment are given the same reference numerals as in the first embodiment, and descriptions thereof are omitted.

FIG. 9 is a sectional view showing main steps of a method for manufacturing a resin tank according to the second embodiment of the present invention.

In the method of manufacturing a resin tank according to the second embodiment, a bladed tool 39 is used in place of the bladed tool 38 of the first embodiment. The conical blade tip 41 is formed on the tool 39 with a blade. When the washer tank 10 is formed, the blade tip 41 is positioned in the inner space (the tool hole 36) in the projection 35. It is provided in advance.

In the method for manufacturing a resin tank according to the second embodiment, the washer tank 10 is formed by the same steps as those shown in FIG. That is, the resin parison expands in the split molds 30 and 32 and the resin parison closely adheres to the peripheral wall of the convex portion 35, so that the through hole 12 of the washer tank 10 is formed. Also in this case, the inner peripheral wall surface of the through hole 12 is not a cut surface, but a convex portion 35.
(Because the peripheral wall of the convex portion 35 becomes the inner peripheral wall surface of the through hole 12 as it is), the roughness of the inner peripheral wall portion (seal surface) can be increased ( The required surface roughness can be secured). Therefore, the sealing performance of the through hole 12 can be ensured.

As described above, since the inner peripheral wall portion (seal surface) of the through hole 12 of the washer tank 10 is formed following the peripheral wall of the convex portion 35, the cutting edge portion 41 of the bladed tool 39 is formed in a conical shape. Even so, the sealing performance of the through hole 12 can be ensured, and the degree of freedom in determining the shape and structure of the blade edge portion 41 of the bladed tool 39 is improved.

Next, FIGS. 10 and 11 are sectional views showing main steps of a method for manufacturing a resin tank according to the third embodiment of the present invention.

In the method for manufacturing a resin tank according to the third embodiment, a bladed tool 43 is used in place of the bladed tool 38 of the first embodiment. A heater is provided at the cutting edge 45 of the tool 43 with a blade.

In the method for manufacturing a resin tank according to the third embodiment, the washer tank 10 is formed by basically the same steps as those shown in FIG.
In step 8, the cylinder 44 is operated and the bladed tool 43 is operated.
Is advanced inward of the hollow body T (the split molds 30 and 32), the heater provided on the blade edge portion 45 is operated, and the resin parison of the hollow body T corresponding to the blade edge portion 45 is heated and melted. The through hole 12 is formed while being cut (FIG. 11).

For this reason, when the bladed tool 43 is advanced toward the inside of the hollow body T to cut the resin parison of the hollow body T and form the through hole 12, a large pressing force is applied to the cut portion of the resin parison. No need to add. Therefore, the bladed tool 4
With the movement of 3, hollow body T (general part of resin parison)
The resin parison corresponding to the through hole 12 can be reliably cut off without unnecessary displacement or movement. Therefore, the product accuracy is further improved. Therefore, the through-hole 12 can be easily formed even in a place where the holding power of the hollow body T (a general part of the resin parison) by the split molds 30 and 32 is low (in other words, the through-hole 12). The split molds 30 and 32 can be set irrespective of the position where the 12 is formed), and the degree of freedom of design and the range of application are expanded.

Next, FIG. 12 and FIG. 13 are sectional views showing main steps of a method for manufacturing a resin tank according to the fourth embodiment of the present invention.

In the method for manufacturing a resin tank according to the fourth embodiment, a bladed tool 48 is used in place of the bladed tool 38 of the first embodiment. The bladed tool 48 has a blade tip 50 formed at the tip and a holding pin 52 protruding therefrom. The holding pin 52 has a function of holding the cut piece S as it is when the cutting tool 48 is advanced to cut the resin parison of the hollow body T corresponding to the cutting edge portion 50.

In the method for manufacturing a resin tank according to the fourth embodiment, the washer tank 10 is formed by basically the same steps as those shown in FIG.
In 6, when the resin parison is pressed against the mold surfaces of the split molds 30 and 32 and is closely attached to the peripheral wall of the bladed tool 48, the resin parison is also closely attached to the periphery of the holding pin 52 (FIG. 12). State shown). Further, in step 108, when the cylinder 44 is operated to advance the bladed tool 48 toward the inside of the hollow body T (the split molds 30 and 32), as shown in FIG. The resin parison of the hollow body T corresponding to
Is formed.

Further, in step 110, the bladed tool 4
When the moving piece 8 is held in the moving state, the cut piece S is positively held by the holding pin 52. Therefore, after that, the bladed tool 48 is connected to the hollow body T (divided molds 30, 3).
Even when detached from 2), the cut piece S is removed from the hollow body T together with the bladed tool 48.

Therefore, the cut piece S of the resin parison does not fall into the hollow body T and remains there. Therefore, the cut piece S remaining after the split molds 30 and 32 are opened and the hollow body T is taken out. The step of taking out S again becomes unnecessary, so that the number of steps can be reduced and the cost can be reduced.

Note that in the fourth embodiment,
Although the holding pin 52 is configured to protrude from the tip of the bladed tool 48, the shape of the holding pin 52 is not limited to this, and may be any configuration that can hold the cut piece S.

For example, a configuration in which a holding groove 60 is formed at the distal end, such as a bladed tool 58 shown in FIG. 14, may be used.
According to the bladed tool 58, when the resin parison is pressed against the mold surfaces of the split molds 30 and 32 and is brought into close contact with the peripheral wall of the bladed tool 58, the resin parison is also in the holding groove 60. Penetrate. Therefore, the bladed tool 58 is connected to the hollow body T
After the resin parison of the hollow body T is cut off by advancing in the inner direction of the (split molds 30, 32), the cut pieces S are held by the holding grooves 60. Therefore, even if the bladed tool 58 is subsequently separated from the hollow body T (the split molds 30 and 32), the cut pieces S are removed from the hollow body T together with the bladed tool 58 and fall into the hollow body T. As a result, there is no need to remove the resection piece S again, and the number of steps can be reduced and the cost can be reduced.

Further, for example, a wedge-shaped holding projection 66 may be formed at the tip as in a bladed tool 64 shown in FIG. According to the bladed tool 64, the holding projection 66
Is formed in a thick inverted wedge shape, so that the holding force of the cut piece S is significantly improved. Therefore, the cut piece S can be more reliably removed from the hollow body T together with the bladed tool 64, which is more effective. Further, as in a bladed tool 70 shown in FIG. 16, a wedge-shaped holding recess 72 may be formed at the tip. Even in this case, similarly, the holding force of the resection piece S is significantly improved, which is more effective.

Next, FIGS. 17 and 18 are sectional views showing main steps of a method for manufacturing a resin tank according to the fifth embodiment of the present invention.

In the method for manufacturing a resin tank according to the fifth embodiment, a bladed tool 100 is used in place of the bladed tool 38 of the first embodiment. The tool 100 with a blade has a blade edge portion 102 formed at the tip. The cutting edge portion 102 is formed to be conical inclining from above to below (only the upper portion has a pointed shape).
When cutting the resin parison of the hollow body T corresponding to the cutting edge portion 102 by moving the bladed tool 100 forward, only the upper part of the resin parison is cut, and the uncut parison piece P remains at the lower part. ing.

In the method for manufacturing a resin tank according to the fifth embodiment, the washer tank 10 is formed by basically the same steps as those shown in FIG.
In FIG. 8, the cylinder 44 is operated to
As shown in FIG. 18, only the upper part of the resin parison of the hollow body T corresponding to the cutting edge portion 102 of the bladed tool 100 is cut when the “0” is advanced toward the inside of the hollow body T (the split molds 30 and 32). The lower portion of the resin parison is bent toward the bottom of the hollow body T as the bladed tool 100 advances without being cut. In this state, in step 110, the bladed tool 100 is held in its moving state, and the hollow body T and the parison piece P are cooled and solidified to form the through holes 12.

As described above, also in the method of manufacturing the resin tank according to the fifth embodiment, it is possible to secure a sealing surface necessary for bringing the grommet 20 into close contact.

Further, in the method of manufacturing the resin tank according to the fifth embodiment, the parison piece P after the through hole 12 is formed is held as it is and falls into the hollow body T and remains. Therefore, there is no need for a step of taking out the parison pieces P remaining after the split molds 30 and 32 are opened and the hollow body T is taken out, so that the number of steps can be reduced and the cost can be reduced.

Further, in the method for manufacturing the resin tank according to the fifth embodiment, the manufactured washer tank 10
When actually used, by the parison piece P,
It is also possible to prevent foreign matter such as dust remaining at the bottom of the washer tank 10 from entering the through hole 12 (in other words, the parison piece P serves as a wall for preventing foreign matter from entering). . Therefore, for example, it is possible to prevent the pump 16 from being damaged due to foreign matter intrusion, and the like, which is more effective.

Incidentally, in the fifth embodiment,
By forming the blade edge portion 102 of the bladed tool 100 in a conical manner from the upper side to the lower side in a conical shape (only the upper part has a sharp shape), the parison piece P that cuts only the upper part of the resin parison and is not cut at the lower part Although it is configured to remain, the shape (configuration) of the bladed tool 100 for cutting so that the parison piece P that is not cut when forming the through hole 12 remains is not limited to this.

For example, as shown in FIGS. 19 and 20, a bladed tool 10 comprising an upper blade portion 104A and a lower body portion 104B.
It may be four. In the bladed tool 104, the upper blade 1
Only 04A is configured to advance toward the inside of the hollow body T (split molds 30, 32).

According to the bladed tool 104, the upper blade 10
By advancing only 4A, the lower part of the resin parison of the hollow body T corresponding to the bladed tool 104 is not cut, but only the upper part of the resin parison is cut. Thereby, the through hole 12 and the parison piece P are formed in the same manner as described above.

Even in this case, it is possible to secure a sealing surface necessary for bringing the grommet 20 into close contact.

Next, FIG. 21 is a sectional view showing main steps of a method for manufacturing a resin tank according to the sixth embodiment of the present invention.

In the method of manufacturing a resin tank according to the sixth embodiment, a bladed tool 110 is used in place of the bladed tool 38 of the first embodiment. The tool 110 with a blade includes a main body 110A and the main body 1A.
Plural needle portions 110B held so as to be relatively movable at 10A
It is constituted by. In this bladed tool 110, only the plurality of needle portions 110B are hollow bodies T (divided molds 30, 3).
It is configured to advance inward in 2).

In the method of manufacturing a resin tank according to the sixth embodiment, the washer tank 10 is formed by basically the same steps as those shown in FIG.
In step 8, the cylinder 44 is operated to set the bladed tool 11
When 0 is advanced to the inside of the hollow body T (the split molds 30 and 32), only the resin parison of the hollow body T corresponding to the needle portion 110B of the bladed tool 110 is cut. Therefore, after the hollow body T and the solidified body are cooled and solidified after the operation of the bladed tool 110, a plurality of holes are formed in the parison piece P in a mesh shape. As a result, in the washer tank 10, as shown in FIGS. 22 (A) and 22 (B), the mesh-shaped filter portion 112 is integrally formed in the through hole 12 to complete the product.

As described above, in the method of manufacturing the resin tank according to the sixth embodiment, not only the sealing surface required for bringing the grommet 20 into close contact can be ensured, but also the mesh Filter section 112
Are integrally formed, so that the manufactured washer tank 1
0 is actually used, the washer tank 10
This has a specific effect that foreign matter such as dust remaining on the bottom of the inside can be prevented from entering the through hole 12. Therefore, for example, the pump 16 due to foreign matter intrusion
Can be prevented beforehand, and there is no need to provide another new filter at the end of the grommet 88.

In the sixth embodiment,
The number and size of the needle portions 110B of the bladed tool 110 (that is, the coarseness of the filter portion 112) can be arbitrarily set, and may be determined according to the target foreign matter.

Next, FIG. 23 is a sectional view showing main steps of a method for manufacturing a resin tank according to the seventh embodiment of the present invention.

In the method of manufacturing a resin tank according to the seventh embodiment, the auxiliary mold 114 is
Is installed. A screw portion 116 is provided on the outer periphery of the auxiliary mold 114, and the screw portion 116 is
0, the tip portion protrudes into a state in which the tip portion enters the inside of the general mold surface of the molding die 30 and the molding die 3
0 and are provided integrally. The protruding end of the auxiliary mold 114 corresponds to the above-mentioned convex 35. Further, the auxiliary mold 114 changes the screwing state of the screw portion 116 and moves the screw portion 116 in the axial direction, so that the tip projecting portion (the convex portion 3) is formed.
This is a configuration in which the projection amount of 5) can be changed. Note that, similarly to the above-described embodiments, the tool hole 36 is formed inside the auxiliary die 114, and the bladed tool 38 and the like are arranged.

In the method of manufacturing the resin tank according to the seventh embodiment, the washer tank 10 is formed by the same steps as those shown in FIG. In other words, the resin parison is expanded in the split molds 30 and 32 and the auxiliary mold 11 is expanded.
The resin parison closely adheres to the peripheral wall of the tip protruding portion (projection 35) of No. 4 to form the through hole 12 of the washer tank 10. Also in this case, the inner peripheral wall surface of the through hole 12 is formed not in a cut plane but in accordance with the peripheral wall of the distal end protruding portion of the auxiliary die 114 (the peripheral wall of the distal end protruding portion of the auxiliary die 114 is directly transparent). (Because it becomes the inner peripheral wall surface of the hole 12), the roughness of this inner peripheral wall portion (seal surface) can be increased (the required surface roughness can be secured). Therefore, the sealing performance of the through hole 12 can be ensured.

Further, in the method of manufacturing a resin tank according to the seventh embodiment, the auxiliary mold 114 forming the convex portion 35 is provided on the molding die 30 by the screw portion 116. The distal end protruding part (convex part 35) is changed by changing the screwing state of
Can be changed, so that the dimension of the inner peripheral wall portion (seal surface) of the through hole 12 can be set arbitrarily. Therefore, it is possible to form the through hole 12 having a size corresponding to the counterpart component to be attached to the through hole 12, and the range of application is greatly expanded.

Next, FIG. 24 is a sectional view showing main steps of a method for manufacturing a resin tank according to the eighth embodiment of the present invention.

In the method for manufacturing a resin tank according to the eighth embodiment, the divided mold 30 has a nesting mold 120A and a nesting mold 1
20B... The configuration is set as the nesting type 120N. In other words, these nesting molds 12 correspond to those having different diameters of the protrusions 35 (through holes 12), protrusions of the protrusions 35 (seal surface dimensions of the inner peripheral wall portion of the through holes 12), and the like.
OA, nested type 120B... Nested type 120N are set in a plurality of types, and are configured to be appropriately replaced (replaced) and used.

In the method of manufacturing the resin tank according to the eighth embodiment, the washer tank 10 is formed by the same steps as those shown in FIG. That is, the resin parison expands in the split molds 30 and 32 and the resin parison closely adheres to the peripheral wall of the convex portion 35, so that the through hole 12 of the washer tank 10 is formed.

In this case, in the method of manufacturing the resin tank according to the eighth embodiment, the diameter of the convex portion 35 (the through hole 12) and the protrusion size of the convex portion 35 (the inner peripheral wall portion of the through hole 12). Since a plurality of types of nesting dies 120A, nesting dies 120B, and the like are set corresponding to those having different sealing surface dimensions), these nesting dies 120A, nesting dies 120B, and the like are appropriately replaced (replaced). If used, it is possible to form the through-hole 12 having an optimal size, and the range of application is greatly expanded.

The cross-sectional shape and size of the blade edge portion 40 of the bladed tool 38 in each of the above-described embodiments can be arbitrarily changed. The through hole 12 can be formed not only in a circular shape but also in an arbitrary shape and size such as a square shape and an elliptical shape.

In each of the above embodiments,
A configuration in which the convex portion 35 (tool hole 36) is provided near the molding die 30 corresponding to the pump fitting portion 14 of the washer tank 10 (hollow body T) (in other words, the pump fitting portion 14).
Although the through hole 12 is formed at a position near the (undercut portion), the forming position of the through hole 12 (that is, the forming position of the convex portion 35) is not limited to this. For example,
The convex portion 35 (tool hole 36) is formed by a pair of split molds 30, 3
A configuration in which the through-hole 12 is formed by providing it at a position A (see FIG. 1) near the mold matching portion (parting line) 33 other than the second cavity 34 (the mold surface for molding the hollow body T).

In this case, a resin parison (product as a product) is formed in the washer tank 10 at a mating portion (parting line) 33 other than the cavity 34 (mold surface for molding the hollow body T) of the split molds 30 and 32. Other parts are taken and held. Therefore, when the bladed tool 38 or the like is advanced toward the inside of the hollow body T to cut the resin parison of the hollow body T and form the through hole 12, the hollow body T is moved with the movement of the bladed tool 38 or the like. (General part of resin parison) does not move or shift unnecessarily,
The resin parison corresponding to No. 2 can be reliably removed. For this reason, the product accuracy of the washer tank 10 is further improved. Further, in each of the above-described embodiments, the configuration is such that the bladed tool 38 and the like are moved by the cylinder 44, but the configuration for moving the bladed tool 38 and the like is not limited to this. For example, the bladed tool 38 and the like may be moved using a cam mechanism, a motor, an electromagnet, or the like.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing main steps of a method for manufacturing a resin tank according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view showing main steps of a method of manufacturing the resin tank according to the first embodiment of the present invention, in a state where a resin cavity is pressed against and closely attached to a mold surface.

FIG. 3 is a cross-sectional view showing main steps of a method for manufacturing the resin tank according to the first embodiment of the present invention, in which a resin parison corresponding to a through hole of a hollow body has been cut away.

FIG. 4 is a flowchart illustrating specific steps of a method for manufacturing a resin tank according to the first embodiment of the present invention.

FIG. 5 is a front view showing a configuration of a main part of a washer tank manufactured by applying the method for manufacturing a resin tank according to the first embodiment of the present invention.

FIG. 6 is a bottom view showing a configuration of a main part of a washer tank manufactured by applying the method for manufacturing a resin tank according to the first embodiment of the present invention.

FIG. 7 shows a mold surface (cavity) of a molding die corresponding to a pump fitting portion (undercut portion) of a washer tank manufactured by applying the method for manufacturing a resin tank according to the first embodiment of the present invention. FIG.

FIG. 8 is a schematic diagram showing a correspondence relationship between a pump fitting portion (undercut portion) and a molding die of a washer tank manufactured by applying the method for manufacturing a resin tank according to the first embodiment of the present invention. FIG.

FIG. 9 is a cross-sectional view showing main steps of a method for manufacturing a resin tank according to the second embodiment of the present invention.

FIG. 10 is a cross-sectional view showing main steps of a method of manufacturing a resin tank according to a third embodiment of the present invention, in a state where a resin cavity is pressed against and closely attached to a mold surface.

FIG. 11 is a cross-sectional view showing main steps of a method for manufacturing a resin tank according to a third embodiment of the present invention, in a state where a resin parison corresponding to a through hole of a hollow body has been cut away.

FIG. 12 is a cross-sectional view showing main steps of a method for manufacturing a resin tank according to a fourth embodiment of the present invention, in a state where a resin cavity is pressed against and closely attached to a mold surface.

FIG. 13 is a cross-sectional view showing main steps of a method for manufacturing a resin tank according to a fourth embodiment of the present invention, in which a resin parison corresponding to a through hole of a hollow body has been cut away.

FIG. 14 is a view showing a modified example of the bladed tool applied to the method of manufacturing the resin tank according to the fourth embodiment of the present invention.
It is sectional drawing corresponding to FIG.

FIG. 15 is a cross-sectional view showing a modified example of the bladed tool applied to the method for manufacturing a resin tank according to the fourth embodiment of the present invention.

FIG. 16 is a cross-sectional view showing a modified example of the bladed tool applied to the method for manufacturing a resin tank according to the fourth embodiment of the present invention.

FIG. 17 is a cross-sectional view showing main steps of a method for manufacturing a resin tank according to a fifth embodiment of the present invention, in a state where a resin cavity is pressed against and closely attached to a mold surface.

FIG. 18 is a cross-sectional view showing main steps of a method for manufacturing a resin tank according to a fifth embodiment of the present invention, in which a resin parison corresponding to a through hole of a hollow body has been cut away.

FIG. 19 is a cross-sectional view showing main steps of a method for manufacturing a resin tank according to a modification of the fifth embodiment of the present invention, in a state where a resin cavity is pressed against and closely attached to a mold surface.

FIG. 20 is a cross-sectional view showing main steps of a method for manufacturing a resin tank according to a modification of the fifth embodiment of the present invention, in which a resin parison corresponding to a through hole of a hollow body has been cut away. is there.

FIG. 21 is a sectional view showing main steps of a method for manufacturing a resin tank according to a sixth embodiment of the present invention.

FIG. 22 shows a washer tank manufactured by the method for manufacturing a resin tank according to the sixth embodiment of the present invention, where (A) is a cross-sectional view and (B) is a front view of a filter portion. .

FIG. 23 is a cross-sectional view showing main steps of a method for manufacturing a resin tank according to the seventh embodiment of the present invention.

FIG. 24 is a perspective view showing main steps of a method for manufacturing a resin tank according to the eighth embodiment of the present invention.

FIG. 25 is a partially cutaway front view of a washer tank manufactured by general hollow molding (blow molding).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Washer tank 12 Through-hole 14 Pump fitting part (undercut part) 16 Pump 30 Mold 32 Mold 34 Cavity 35 Convex part 36 Tool hole 38 Tool with blade 39 Tool with blade 40 Blade tip 41 Blade tip 43 Blade tool 45 Blade tip part 48 Blade tool 50 Blade tip part 52 Holding pin 58 Tool with blade 60 Holding groove 64 Tool with blade 66 Holding convex part 70 Tool with blade 72 Holding concave part 100 Tool with blade 104 Tool with blade 110 Tool with blade 114 Auxiliary type 120A nesting type 120B nesting type T hollow body S cut piece P parison piece

Claims (5)

[Claims] 1. A method for manufacturing a resin tank having a through hole in a side wall portion, wherein a convex portion having a cylindrical shape corresponding to the through hole is inserted into the inside of the mold from the mold surface. A tool with a cutting edge, which is provided in the mold in advance and protrudes into a state, is arranged in a columnar shape and has a cutting edge at the tip, is arranged in the cylindrical convex portion, and the resin parison is expanded in the mold and the resin is formed. Pressing the parison against the molding die and bringing the resin parison into close contact with the peripheral wall of the convex portion, forming a hollow body in a state in which the inner peripheral wall surface of the through hole is molded by the peripheral wall of the convex portion; Advancing the bladed tool inward of the hollow body, cutting off the resin parison of the hollow body corresponding to the cutting edge of the bladed tool to form the through-hole, From the hollow body and the molding The take out the hollow body the through hole is formed open, method for producing a resin-made tank, characterized in that. 2. A heater is provided at a cutting edge portion of the bladed tool, and when the resin parison of the hollow body corresponding to the blade edge is cut by the bladed tool, cutting is performed while melting the resin parison by the heater. The method for producing a resin tank according to claim 1, wherein: 3. When the resin parison of the hollow body corresponding to the cutting edge is cut by the tool with the blade, the cut piece is held by the tool with the blade, and the tool with the blade is detached from the hollow body. The method for manufacturing a resin tank according to claim 1, wherein the cut piece is removed from the hollow body together with the bladed tool. 4. The through hole is formed by providing the convex portion near a matching portion of a pair of male and female split molds. The method for producing the resin tank described in the above. 5. A cavity of the forming die for forming an undercut portion in the hollow body, and the projecting portion is provided near a position of the forming die corresponding to the undercut portion, so that the through hole is formed. The method for producing a resin tank according to any one of claims 1 to 4, wherein the resin tank is molded.