JP2010085717A - Porous ceramic molding and fastening method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fastening method for smoothly fastening a porous ceramic molding to a component, and to provide a porous ceramic molding fastened using the fastening method. <P>SOLUTION: A lubricant K is applied to a screw SR1 formed on a pressing ring 11 as a component to be fastened, or to a screw SR2 of a mirror frame 10 made of the porous ceramic molding that has the screw SR2 to be screw-engaged with the screw SR1. Subsequently, the pressing ring 11 is fastened to the mirror frame 10 made of the porous ceramic molding. Smooth fastening is achieved and accordingly chipping of the screws is prevented. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a porous ceramic molded product in which a screw that is screwed with a screw formed on a mating part is formed, and a fastening method when the screw of the mating part is fastened to the screw of the porous ceramic molded product.

  Recently, cameras have been deployed in automobiles. Many of the cameras deployed in automobiles display the state of a driver's blind spot on the display screen by utilizing the fact that navigation systems are widespread and display screens are provided in the driver's seat. .

  By the way, automobiles are sometimes exposed to the outdoors in the hot weather in summer and the coldest outdoors in winter, and the on-vehicle camera needs to operate normally under such an extremely wide temperature environment. In order to guarantee this normal operation, the performance required for lens assemblies applied to in-vehicle cameras does not cause general characteristics such as light weight and robustness, and does not cause blur due to temperature changes. Therefore, there is little expansion and contraction due to temperature. In order to satisfy these requirements, a ceramic lens barrel has been considered (see, for example, Patent Documents 1 and 2). The present applicant has proposed applying a porous ceramic to an optical component (see, for example, Patent Document 3). The term “porous” as used in the specification of Patent Document 3 refers to a porous body having a porosity of 10% or more.

  Here, in Patent Document 4, for example, a lens assembly in which a lens is fixed to a lens barrel by inserting a lens and a spacing ring from the front opening of the lens barrel and screwing a presser ring on the front side of the lens barrel. Is described. A configuration when a porous ceramic lens barrel is applied to the configuration of Patent Document 4 will be described.

  FIG. 1 is a diagram showing a configuration example of a lens assembly including a porous ceramic lens barrel.

  The lens assembly 1 shown in FIG. 1 includes a lens barrel 10, and the lens barrel 10 is provided with a hollow portion 100 having an objective side opening 101 and an imaging side opening 102. A male screw SR1 is formed on the outer periphery of the lens barrel 10 on the objective side, and a plurality of lenses L1 to L4 and a plurality of spacing rings SP1 to SP3 are inserted from the objective side opening 101 with their optical axes aligned. In this example, a plurality of lenses L1 to L4 and a plurality of spacing rings SP1 to SP3 are alternately inserted as a plurality of optical members into the hollow portion 100 of the lens barrel 10 sequentially.

  Further, in the lens assembly 1 of FIG. 1, a plurality of optical lenses L1 to L4 and spacing rings SP1 to SP3 inserted in the hollow portion 100 of the lens barrel 10 are pressed and fixed from the objective side opening 101. The holding ring 11 is provided. The holding ring 11 exposes the mounting opening 110 into which the objective-side portion of the lens barrel 10 enters, and the central portion of the lens L1 inserted closest to the objective among the plurality of lenses inserted into the lens barrel. A female screw SR2 screwed with the male screw SR1 is formed on the inner wall inside the mounting opening, and is positioned closest to the object side by screwing the male screw SR1 and the female screw SR2. The peripheral edge of the objective side surface of the lens L1 is pressed.

  The lens assembly 1 shown in FIG. 1 is assembled by pressing the plurality of lenses L1 to L4 and the plurality of spacing rings SP1 to SP3 in the lens barrel 10 toward the image forming side opening by the presser ring 11.

However, the porous ceramic molded product used in the above-mentioned lens barrel generally has a drawback that the surface is rough and rough as compared with normal ceramics. For this reason, when a screw is formed on a porous ceramic molded product, the screw formed on the counterpart component cannot be smoothly screwed into the screw of the porous ceramic molded product. This disadvantage can cause the screw to chip during screwing.
JP 2006-289991 A JP 2006-292927 A JP 2007-238430 A JP 2007-279557 A

  In view of the above circumstances, an object of the present invention is to provide a fastening method for smoothly fastening a porous ceramic molded product and a counterpart part, and a porous ceramic molded product fastened by employing the fastening method.

The ceramic molded product of the present invention that achieves the above object is a porous ceramic molded product in which a screw that is screwed with a screw formed on a counterpart component is formed,
A lubricant is applied to a screwed portion with the mating part.

  A porous body is a porous body having a porosity of 10% or more.

  According to the ceramic molded product, since the lubricant is applied to the threaded portion with the counterpart component, the screw formed on the counterpart component can be smoothly fastened to the screw formed on the ceramic molded product. . Thus, if the screw formed on the mating part can be smoothly fastened to the screw of the porous ceramic molded product, the chipping of the screw formed on the porous ceramic is prevented.

  Here, the lubricant is preferably a solid lubricant.

  If the lubricant is a liquid and the viscosity of the lubricant is too low, the liquid tends to penetrate into the pores formed on the surface of the porous ceramic, and a lubricant film is not easily formed on the surface of the screw. It is also possible. Accordingly, the lubricant is preferably a solid lubricant. When a solid lubricant is used, a lubricating film is suitably formed on the screw surface.

  Further, if the lubricant film can be formed on the screw surface using the solid lubricant, the effect of improving the circumference of the adhesive can be obtained when the adhesive is press-fitted for screw locking later.

  The lubricant is a solid lubricating component mainly composed of one or more selected from molybdenum disulfide, graphite, and PTFE, a polyamideimide resin, an epoxy resin, and an acrylic resin. It may be a solid lubricant composed of any one or a plurality of selected binders. Then, the solid lubricant spreads well on the surface of the screw of the ceramic molded product, and a lubricating film is suitably formed.

  Further, the lubricant may be a lubricant solidified by drying and containing a polymer resin as a main component. When the main component of the lubricant is made of a polymer resin, even if it is liquid, it does not penetrate into the pores, and a lubricating film is successfully formed on the surface of the ceramic lens frame through a drying process.

In addition, the porous ceramic molded product has an objective-side opening and an imaging-side opening, and a male screw is formed on the outer periphery of the objective-side so as to be screwed with a mating part. A plurality of optical members are aligned with the optical axis from the objective-side opening. Is a porous ceramic lens barrel,
A mounting opening in which a part on the objective side of the lens barrel enters, and a central portion of the first optical member inserted in the most objective side among the plurality of optical members inserted in the lens barrel. A female screw that is screwed with the male screw is formed on the inner wall inside the mounting opening, and the male screw and the female screw are screwed to each other on the objective side of the first optical member. The porous ceramic molded product is suitably applied to a mode in which the presser ring holds the peripheral edge of the surface. The presser ring at this time may be made of, for example, aluminum or may be made of ceramic.

Moreover, the fastening method of the present invention that achieves the above-described object is as follows.
A method of fastening a porous ceramic molded article formed with a screw to be screwed with a screw formed on a counterpart part and the counterpart part,
A lubricant application step of applying a lubricant to at least one of the screw formed on the porous ceramic molded article and the screw formed on the counterpart part;
After the lubricant is applied in the lubricant application step, the method includes a fastening step of screwing the screw formed on the porous ceramic molded product and the screw formed on the counterpart component.

  According to the fastening method of the present invention, after the lubricant is applied to at least one of the screw formed on the porous ceramic molded product and the screw formed on the counterpart component in the lubricant application step. Since the screw formed on the porous ceramic molded product and the screw molded on the mating part are screwed together, it is fastened smoothly. As a result, the screw is prevented from being chipped.

  As described above, the fastening method for smoothly fastening the porous ceramic molded product and the counterpart part and the porous ceramic molded product fastened by employing the fastening method are realized.

  Embodiments of the present invention will be described below.

  FIG. 2 is a diagram showing a configuration of a lens assembly in which the porous ceramic molded product of the present invention is applied to a lens frame. FIG. 2 shows a view of the same configuration as FIG. 1 except that the lubricant K is applied.

  2A shows a state after the presser ring 11 is screwed into the lens frame 10, and FIG. 2B shows a state before the presser ring 11 is screwed into the lens frame 10. As shown in FIG. It is shown.

  When the presser ring 11 is screwed into the lens frame 10 after the lubricant K is applied as shown in FIG. 2 (b), the presser ring 11 is smoothly fastened to the lens frame 10 as shown in FIG. 2 (a). This prevents the screw from being chipped.

  Here, the present applicant conducted an experiment using a solid lubricant called Mori Dry MD1670 (registered trademark) manufactured by Sumiko Lubricant Co., Ltd. as the lubricant K, and the results will be described.

  The Molydry MD1670 (registered trademark) lubricant is a solid lubricant having molybdenum disulfide as a main lubricant component and a resin such as polyamide-imide resin as a binder.

  The present applicant applies a thinning agent obtained by adding a diluent solvent to the above-described solid lubricant MD1670 (registered trademark) and applying it to the screw surface of the lens frame 10 which is a porous ceramic molded product. After firing for a minute, the presser ring 11 made of aluminum was screwed into a screw of a mirror frame, which is a porous ceramic molded product, and an attempt was made. As a result, the aluminum presser ring 11 could be smoothly screwed and fastened to the screw of the lens frame 10 which is a porous ceramic molded product.

  Furthermore, the present applicant was able to confirm that when the adhesive was pressed into the threaded portion for screw locking, the adhesive penetrated widely and a strong adhesive state was obtained.

  When the solid lubricant film K is formed on the surface of the screw in this way, the mating part can be smoothly fastened to the ceramic molded product, and the screw is effectively fixed by injecting an adhesive that becomes a screw lock. Can do.

  As the solid lubricant K, it is possible to use an epoxy resin or an acrylic resin as a binder. Further, the solid lubricant may be one in which graphite and PTFE (tetrafluoroethylene resin) are the main lubricant components instead of molybdenum disulfide. In this case, a binder in which an epoxy resin or an acrylic resin is used in addition to the above polyamideimide resin may be used.

  Furthermore, the lubricant is a solid lubricating component mainly composed of any one or more selected from the above molybdenum disulfide, the above graphite, and PTFE, a polyamideimide resin, an epoxy resin, and an acrylic resin. It may be a solid lubricant composed of any one or plural binders selected from the inside.

  Here, in order to obtain the lens assembly of FIG. 2, a fastening method when fastening the screw of the mating part to the screw formed in the porous ceramic molded product will be described.

  FIG. 3 is a process diagram for explaining an example of the fastening method.

  First, in the lubricant application step S301, a solid lubricant (Molydry MD1670 (registered trademark) or the like) is applied to at least one of the screw formed on the porous ceramic molded product and the screw formed on the counterpart component. To do. Proceeding to the next fastening step S302, the screw formed on the porous ceramic molded product and the screw formed on the mating part are screwed together.

  After the solid lubricant is applied to at least one of the screw formed on the porous ceramic molded product and the screw formed on the counterpart component, the screw formed on the porous ceramic molded product and the counterpart When the screw molded into the part is screwed, the counterpart part is smoothly fastened to the ceramic molded product. When the screws are smoothly tightened in this way, the screws are not chipped.

  The reason why the solid lubricant is used is that when a liquid lubricant is used, it is difficult for a lubricant film to be formed by soaking the lubricant into a large number of pores on the surface of the porous ceramic.

  As described above, the fastening method for smoothly fastening the porous ceramic molded product and the counterpart part and the porous ceramic molded product fastened by employing the fastening method are realized.

It is a figure which shows an example of a structure of the lens assembly used for the camera mounted in a motor vehicle. It is a figure which shows the structure of the lens assembly by which the porous ceramic molded article of this invention was applied to the lens frame. It is process drawing explaining an example of the fastening method.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Lens assembly 10 Mirror frame L1-L4 Lens SP1-SP3 Space ring K Solid lubricant

Claims (7)

A porous ceramic molded product in which a screw that is screwed with a screw formed on a counterpart part is formed,
A porous ceramic molded product, wherein a lubricant is applied to a screwed portion with the counterpart component.   The porous ceramic molded article according to claim 1, wherein the lubricant is a solid lubricant.   The lubricant is selected from the group consisting of a solid lubricating component mainly composed of one or more selected from molybdenum disulfide, graphite, and PTFE, a polyamide-imide resin, an epoxy resin, and an acrylic resin. 3. The porous ceramic molded article according to claim 2, which is a solid lubricant comprising any one or a plurality of selected binders.   The porous ceramic molded article according to claim 1, wherein the lubricant is a lubricant that is solidified by drying and contains a polymer resin as a main component. The porous ceramic molded product has an objective-side opening and an imaging-side opening, and a male screw is formed on the outer periphery of the objective to be screwed with a mating part. A plurality of optical members are aligned with the optical axis from the objective-side opening. It is a porous ceramic lens barrel that is inserted,
A mounting opening into which the objective part of the lens barrel enters and a central portion of the first optical member that is inserted closest to the object among the plurality of optical members that are inserted into the lens barrel. And a female screw that is screwed with the male screw is formed on the inner wall inside the mounting opening, and the male optical screw and the female screw are screwed to each other to form the first optical member. The porous ceramic molded article according to any one of claims 1 to 4, wherein the porous ceramic molded article is a presser ring that presses a peripheral edge of a surface on the objective side. A method of fastening a porous ceramic molded article formed with a screw to be screwed with a screw formed on a counterpart part and the counterpart part,
A lubricant application step of applying a lubricant to at least one of the screw formed on the porous ceramic molded article and the screw formed on the counterpart part;
A fastening method comprising: a fastening step of screwing a screw formed on the porous ceramic molded product and a screw formed on a mating part after the lubricant is applied in the lubricant applying step. .   The fastening method according to claim 6, wherein the lubricant application step is a step of applying a solid lubricant to the at least one screw.

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