JP2019077119A - Resin molded product and method for producing resin molded article - Google Patents

Abstract

To provide a resin molded product and a method of producing a resin molded product that can suppress a contamination of burrs into an internal passage.SOLUTION: An oil strainer includes an upper case 20 made of a laser permeable resin, a lower case 10 made of a laser absorbing resin, and an internal passage P divided by being joined together by laser welding in a state in which a joint portion 26 of a flange 24 of the upper case 20 and a joint portion 26 of a flange 14 of the lower case 10 are abutted together. A thickness T of the joint portion 26 of the flange 24 of the upper case 20 to the flange 14 of the lower case 10 is gradually thickened toward the internal passage P.SELECTED DRAWING: Figure 2

Description

  The present invention includes a first member made of a laser-permeable resin and a second member made of a laser-absorbing resin, and the first member and the second member are joined together by laser welding in a state where they are attached to each other. TECHNICAL FIELD The present invention relates to a resin molded product having the internal passage and a method of manufacturing the resin molded product.

  Conventionally, as a resin molded product of this type, there is, for example, an oil strainer which is disposed in an oil pan of an internal combustion engine and removes relatively large foreign matter mixed in the oil (see, for example, Patent Document 1).

  The oil strainer described in Patent Document 1 includes an upper case, a lower case, and a filter medium provided between the cases. A filtration chamber is formed by welding the upper case and the lower case in a butt-matched state. The filter material is fixed to the upper case and the lower case by a part of the molten resin generated when the butt parts of the upper case and the lower case are welded into the mesh of the filter material and hardened.

Patent No. 3748251

  By the way, in the oil strainer described in Patent Document 1, burrs generated when welding the upper case and the lower case are in the filtration chamber (inner passage) from between the upper case and the filter medium and between the lower case and the filter medium. There is a risk of entering. In addition, it is difficult to remove the burr that has entered the filtration chamber. As a result, if the oil and the burr are supplied to the drive unit such as the oil pump, there is a possibility that the drive unit may malfunction.

  In addition, such a subject is not restricted to the oil strainer of an internal combustion engine, For example, it arises in general also in resin molded products, such as an air cleaner and the intake manifold of an internal combustion engine, in common.

  An object of the present invention is to provide a resin molded product and a method of manufacturing the resin molded product which can suppress the entry of burrs into the inner passage.

  A resin molded article for achieving the above object comprises a first member made of a laser permeable resin and a second member made of a laser absorbing resin, and the first member and the second member are attached to each other. A resin molded product having an internal passage partitioned by being bonded to each other by laser welding in a state where the portion of the joint portion of the first member to the second member is on the side close to the internal passage Is thicker than the thickness of the portion of the side separated from the internal passage.

  Further, a method of manufacturing a resin molded product for achieving the above object comprises a first member made of a laser transmitting resin and a second member made of a laser absorbing resin, and the first member and the second member A method of manufacturing a resin molded product having an internal passage partitioned by joining together a member and joining them together by laser welding, the internal passage of a joint portion of the first member with the second member The thickness of the inner portion adjacent to the inner passage is set to be thicker than the thickness of the outer portion spaced from the inner passage.

In general, in a laser transmitting resin, the amount of attenuation of laser light increases as the distance through which the laser light passes increases.
According to the above configuration and the above method, when the first member and the second member are put together and laser welded, the portion of the joint portion of the first member on the side closer to the internal passage (hereinafter referred to as the inner side) The amount of attenuation of the laser light is larger than that of the portion (hereinafter, the outer side) of the side which is separated from the inner passage. For this reason, the calorific value accompanying the absorption of the laser light at the bonding portion of the second member is smaller at the inner portion than at the outer portion. As a result, in each of the joints of the first member and the second member, the resin is more likely to melt on the outer side than on the inner side, and burrs resulting from the melting of the resin occur on the outer side than the inner side. It will be easier. Therefore, the entry of burrs into the internal passage can be suppressed.

  According to the resin molded article and the method for producing a resin molded article of the present invention, the effect of suppressing the mixing of the burr into the inner passage can be obtained.

The whole sectional view of an oil strainer about one embodiment of a resin-molding article. The expanded sectional view of the part corresponding to the A section of FIG. FIG. 7 is a cross-sectional view corresponding to FIG. 2, showing a first state in the middle of laser welding. FIG. 7 is a cross-sectional view corresponding to FIG. 2, showing a second state in which melting of the resin has progressed more than the first state, which is a state in the middle of laser welding. The expanded sectional view shown centering on the junction part of the flange of a lower case, and the flange of an upper case about the modification of an oil strainer. The expanded sectional view shown centering on the junction part of the flange of a lower case, and the flange of an upper case about other modifications of oil strainer.

Hereinafter, with reference to FIGS. 1 to 4, an embodiment in which a method for manufacturing a resin molded product and a resin molded product is embodied as an oil strainer for an internal combustion engine and a method for manufacturing the same will be described.
First, the configuration of the oil strainer of the present embodiment will be described with reference to FIGS. 1 and 2.

  As shown in FIG. 1, the oil strainer is disposed in an oil pan of an internal combustion engine to remove relatively large foreign matter mixed in the oil. The oil strainer includes a lower case 10 having an opening 11a at an upper portion, an upper case 20 having an opening 21a at a lower portion, and a filter medium 30 provided between the opening 11a of the lower case 10 and the opening 21a of the upper case 20. Have.

  The lower case 10 has a side wall 11 and a bottom wall 12 surrounding the opening 11a. A cylindrical inlet 13 is connected to the bottom wall 12. Moreover, the flange 14 which protrudes toward the outer peripheral side is provided in the periphery of the opening part 11a over the perimeter.

The lower case 10 is integrally formed of, for example, a laser-absorptive thermoplastic resin colored in black.
The upper case 20 has a side wall 21 and a top wall 22 surrounding the opening 21a. A cylindrical outlet 23 is connected to the top wall 22. Moreover, the flange 24 extended toward the outer peripheral side is provided in the periphery of the opening part 21a over the perimeter.

The upper case 20 is integrally formed of, for example, a transparent or translucent laser-permeable thermoplastic resin.
The flange 14 of the lower case 10 and the flange 24 of the upper case 20 are joined together by laser welding over the entire circumference. An inner passage P is divided by the lower case 10 and the upper case 20.

  In the following, of the projecting direction W (the left and right direction in FIGS. 1 and 2) of the flange 14 of the lower case 10, the side approaching the internal passage P is the inner side (right side in FIG. 2) Is described as the outside (left side in FIG. 2).

  As shown in FIG. 2, at a central portion in the projecting direction W of the flange 14 of the lower case 10, a projecting portion 15 projecting toward the flange 24 side of the upper case 20 is provided. The protrusion 15 includes a joint 16 joined to the flange 24 of the upper case 20 and a step 17 adjacent to the inside of the joint 16 and forming a gap S between the flange 24 of the upper case 20 and the joint 24. It is provided.

  On the inner side of the flange 24 of the upper case 20, more specifically on the inner side of the gap S, a plurality of holding portions 27 projecting toward the flange 14 side of the lower case 10 are mutually spaced in the circumferential direction of the opening 21a. Are provided. The inner surface of each holding portion 27 is flush with the inner peripheral surface of the side wall 21. Here, the width W2 of each holding portion 27 in the projecting direction W is set smaller than the width W1 between the step 17 and the opening 11a in the projecting direction W (W2 <W1).

  As shown in FIGS. 1 and 2, the filter medium 30 is made of, for example, a metal mesh material. The peripheral edge portion 31 of the filter medium 30 is located outside the holding portions 27 of the upper case 20, and is opposed to the inner circumferential surface of the step portion 17 of the lower case 10 via a gap.

As shown in FIG. 2, a gap G is set between the flange 24 of the upper case 20 and the filter medium 30 so as to allow displacement of the filter medium 30 to such an extent that the filter medium 30 does not come inward.
In the present embodiment, the thickness T of the flange 24 of the upper case 20 is gradually increased toward the inside. More specifically, the opposite surface 25 (the lower surface in the figure) of the flange 24 of the upper case 20 facing the flange 14 of the lower case 10 has an opening except for the joint 26 joined to the joint 16 of the lower case 10. It is considered as a flat surface along a virtual plane including 21a. On the other hand, the surface 28 (upper surface in the figure) opposite to the facing surface 25 of the flange 24 of the upper case 20 is inclined so as to be separated from the facing surface 25 inward.

  In the present embodiment, the upper case 20 and the opening 21a correspond to the first member and the first opening, respectively. The lower case 10 and the opening 11a correspond to the second member and the second opening, respectively.

Next, the procedure of manufacturing the oil strainer and the operation of the present embodiment will be described with reference to FIGS. 3 and 4.
When manufacturing the oil strainer of the present embodiment, first, the flange 14 of the lower case 10 and the flange 14 of the lower case 10 are positioned with the peripheral edge 31 of the filter medium 30 positioned between the flange 14 of the lower case 10 and the flange 24 of the upper case 20. , The flange 24 of the upper case 20 is butted.

Subsequently, as shown by an arrow in FIG. 3, laser light is emitted from the flange 24 side of the upper case 20 toward the flange 14 side (from the upper side to the lower side of the same figure) of the lower case 10.
The laser light passes through the flange 24 of the upper case 20 and then reaches the joint portion 16 of the flange 14 of the lower case 10 and is absorbed.

In general, in a laser transmitting resin, the amount of attenuation of laser light increases as the distance through which the laser light passes increases.
According to the present embodiment, since the thickness T (see FIG. 2) of the bonding portion 26 of the upper case 20, that is, the plate thickness of the flange 24 is gradually increased toward the inner side, the inner portion of the bonding portion 26 The amount of attenuation of the laser light increases. For this reason, the calorific value accompanying the absorption of the laser light at the bonding portion 16 of the lower case 10 decreases toward the inside portion.

  As a result, as shown in FIG. 3 and FIG. 4 in order, the bonding portion 16 generates heat and melts as it absorbs laser light, and the bonding portion 26 of the flange 24 of the upper case 20 joined to the bonding portion 16 is also It is melted by the heat transmitted from the bonding portion 16. Here, as described above, the resin is more likely to be melted as the outer portion of the bonding portions 16 and 26 is formed, and burrs resulting from the melting of the resin are more likely to be generated outside than inside.

In the same drawing, the molten resin D is a mixture of the resin constituting the lower case 10 and the resin constituting the upper case 20.
According to the resin molded product and the method for manufacturing a resin molded product according to the present embodiment described above, the following effects can be obtained.

  (1) The oil strainer includes an upper case 20 made of a laser-permeable resin and a lower case 10 made of a laser-absorbing resin, and a joint portion 26 of the flange 24 of the upper case 20 and a joint portion 26 of the flange 14 of the lower case 10 An inner passage P is defined by being joined together by laser welding in a state in which they are butted together. The thickness T of the joint portion 26 of the flange 24 of the upper case 20 to the flange 14 of the lower case 10 is gradually increased toward the inside.

  According to such a configuration, since the function of the above-described embodiment is exerted, it is possible to precisely control the amount of melting of the resin and hence the amount of generation of the burr, and it is possible to suppress the contamination of the burr into the internal passage P. .

Moreover, since it can suppress that a burr mixes in the oil which flows out through the outlet 23, generation | occurrence | production of the malfunction of the drive part of the oil supply system resulting from a burr can be suppressed.
(2) The flange 14 of the lower case 10 is provided with a step 17 that forms a gap G between the flange 24 of the upper case 20 and the flange 24 of the upper case 20 adjacent to the inner side with respect to the joint 16 with the upper case 20. .

  According to such a configuration, even if the molten resin leaks inward at each of the joint portions 26 and 16 of the flange 24 of the upper case 20 and the flange 14 of the lower case 10, the molten resin thus leaked is the gap G As a result of hardening in the above, it becomes integral with the flange 24 of the upper case 20 and the flange 14 of the lower case 10, and it becomes difficult to be separated. Therefore, the entry of burrs into the internal passage P can be further suppressed.

  (3) In the method of manufacturing the oil strainer, the thickness T of the joint portion 26 of the flange 24 of the upper case 20 to the flange 14 of the lower case 10 is set to be gradually thicker toward the inside.

According to such a method, the same function and effect as the above function and effect (1) can be exhibited.
<Modification>
In addition, the said embodiment can also be changed as follows, for example.

  In the upper case 20 of the above embodiment, although the plurality of holding portions 27 are provided at intervals in the circumferential direction of the opening 21a, the holding portions are provided over the entire circumferential direction of the opening 21a. You may do so. In this case, since the joints 16 and 26 and the inner passage P are separated by the holding portion over the entire circumference, it is possible to further suppress the entry of burrs into the inner passage P.

  In the upper case 20 of the above embodiment, the thickness T of the joint portion 26 (the plate thickness of the flange 24) is gradually increased toward the inside, but the thickness of the joint portion may be changed stepwise. Good. Even in this case, it is possible to obtain the effect according to the operation effect (1) of the above embodiment.

-The level | step-difference part 17 of lower case 10 of the said embodiment can also be abbreviate | omitted. Even in this case, the effect (1) of the above embodiment can be obtained.
-In the said embodiment, the lower case 10 was comprised with the laser absorptive resin material, and the upper case 20 was comprised with the laser permeable resin material. Instead of this, for example, as shown in FIG. 5, the lower case 110 may be made of a laser-permeable resin material, and the upper case 120 may be made of a laser-absorbing resin material. The same components as those of the first embodiment are denoted by the same reference numerals, and the corresponding components are indicated by adding a symbol "1 **" obtained by adding 100 to the symbol "**" of the first embodiment. Duplicate descriptions will be omitted.

  As shown in FIG. 5, at the inner end of the flange 114 of the lower case 110, a holding portion 118 projecting toward the flange 124 side of the upper case 120 is provided over the entire circumference. The peripheral portion 31 of the filter medium 30 is held between the holding portion 118 and the flange 124 of the upper case 120. Further, at the outer end of the flange 114, a projecting portion 119 that protrudes toward the flange 124 side (upper side in the drawing) of the upper case 120 is provided over the entire circumference.

  The flange 124 of the upper case 120 is provided with an annular protrusion 129 that protrudes between the holding portion 118 of the lower case 110 and the protrusion 119. The tip of the annular projection 129 is provided with a projection 125 that protrudes outward. A joint portion 126 joined to the projection portion 119 of the flange 114 of the lower case 110 and a lower case adjacent to a side (lower side in the figure) closer to the inner passage P with respect to the joint portion 126 A stepped portion 127 is formed between the flange 110 and the flange 114 to form a gap S.

Here, the thickness of the protruding portion 119 (joint portion 116) of the lower case 110 is gradually increased toward the side closer to the internal passage P (the lower side in the figure).
In the oil strainer having such a configuration, as shown by the arrow in the figure, the laser beam is irradiated from the side of the protrusion 119 of the lower case 110 toward the joint 126 of the upper case 120 (from left to right in the figure). Thus, the joint portion 116 of the lower case 110 and the joint portion 126 of the upper case 120 are joined by laser welding.

Also in the oil strainer in this modification, it is possible to achieve the effects according to the effects (1) to (3) of the above embodiment.
For example, as shown in FIG. 6, the lower case 210 may be made of a laser-permeable resin material, and the upper case 220 may be made of a laser-absorbing resin material. The same reference numerals are given to the same components as those of the above-described modification, and a reference symbol “2 **” is obtained by adding 100 to the reference “1 **” of the above-described modification. The explanation is omitted.

  As shown in FIG. 6, at the outer end of the flange 214 of the lower case 210, a protrusion 219 projecting toward the flange 224 side (upper side in the figure) of the upper case 220 is provided over the entire circumference. The flange 214 is not provided with a portion corresponding to the holding portion 118 (see FIG. 5) of the above-described modified example. Further, the flange 224 of the upper case 220 is not provided with a portion corresponding to the annular projection 129 (see FIG. 5) of the above-described modified example. The peripheral portion 31 of the filter medium 30 is held between the flange 214 of the lower case 210 and the flange 224 of the upper case 220. A joint portion 216 provided on the inner circumferential surface of the projecting portion 219 and a joint portion 226 which is an outer circumferential surface of the flange 224 of the upper case 220 are joined.

Here, the thickness of the protruding portion 219 (joint portion 216) of the lower case 210 is gradually increased toward the side closer to the internal passage P (lower side in the figure).
Also in the oil strainer having such a configuration, the laser light is irradiated from the side of the protrusion 219 of the lower case 210 toward the joint 226 of the upper case 220 (from the left side to the right side in the figure). The joint 216 and the joint 226 of the upper case 220 are joined by laser welding.

Also in the oil strainer in this modification, it is possible to achieve the effects according to the effects (1) to (3) of the above embodiment.
The resin molded product according to the present invention and the method for manufacturing the same can be applied to an oil strainer other than the oil strainer for an internal combustion engine such as an oil strainer for an automatic transmission and a method for manufacturing the same. The present invention can also be applied to a device for filtering a fluid other than oil, such as an air cleaner that filters air, and a method of manufacturing the same. The filter medium is not limited to metal. The material to be the filter medium may be appropriately changed according to the fluid to be filtered.

  The resin molded product according to the present invention and the method for producing the same are not limited to those applied to a fluid filtering device and a method for producing the same. For example, the present invention can be applied to a duct such as an intake manifold of an internal combustion engine.

DESCRIPTION OF SYMBOLS 10 lower case (2nd member) 11 side wall 11a opening part (2nd opening part) 12 bottom wall 13 inlet 14 flange 15 protrusion part 16 junction part 17 step difference Section 20 Upper case (first member) 21 Side wall 21a Opening (first opening) 22 Top wall 23 Outlet 24 Flange 25 Opposing surface 26 Joint 26 27: holding portion, 28: opposite surface, 30: filter material, 31: peripheral portion, 110, 210: lower case (first member), 111, 211: side wall, 111a, 211a: opening (first opening) , 114, 214: flange, 116, 216: joint portion, 118: holding portion, 119, 219: projecting portion, 120, 220: upper case (second member), 121, 221: side wall, 121a, 221a: opening portion (Second opening) 124, 224 ... flange, 125 ... protrusion, 126, 226 ... joint, 127 ... stepped portion, 129 ... annular projection, D ... molten resin, G, S ... gap, P ... internal passage.

Claims (5)

A first member made of a laser transmitting resin and a second member made of a laser absorbing resin are provided, and the first member and the second member are joined together by laser welding in a state where they are attached to each other A resin molded article having a partitioned internal passage, wherein
The thickness of the portion of the first member in the joint with the second member on the side closer to the internal passage is thicker than the thickness of the portion on the side separated from the internal passage.
Resin molded products. The thickness of the joint portion of the first member with the second member is gradually increased toward the side closer to the internal passage.
The resin molded article according to claim 1. The second member is provided with a step portion which forms a gap between the first member and a portion adjacent to the side adjacent to the internal passage with respect to the joint portion with the first member.
The resin molded article according to claim 1 or 2. The first member is a first case having a first opening and an inlet,
The second member is a second case having a second opening facing the first opening and an outlet.
A filter medium is provided between the first opening and the second opening for filtering the fluid flowing in the internal passage from the inlet to the outlet,
In either one of the peripheral portion of the first opening and the peripheral portion of the second opening, a holding portion is provided which protrudes toward the other and holds the filter medium together with the other peripheral portion.
The bonding portion is provided at a peripheral edge portion of the first opening portion and a peripheral edge portion of the second opening portion, respectively, at a portion spaced apart from the internal passage than the holding portion.
The resin molded article according to any one of claims 1 to 3. A first member made of a laser transmitting resin and a second member made of a laser absorbing resin are provided, and the first member and the second member are put together and separated by joining them by laser welding. A method of producing a resin molded product having an internal passage, comprising:
The thickness of the portion on the side closer to the internal passage in the joint portion with the second member in the first member is set to be thicker than the thickness on the side separated from the internal passage.
Method of producing a resin molded article.