JP2011256829A - Case and mounting boss - Google Patents

Abstract

PROBLEM TO BE SOLVED: To sufficiently reduce the weight of a fan case 1 while enhancing the degree of freedom of a mounting position in the case axial direction (fore-and-aft direction) of an auxiliary machine 7.SOLUTION: The case includes a cylindrical case body 9 composed of a composite material of reinforced fibers and thermosetting resin, and a mounting boss 21 disposed on the outer peripheral face of the case body 9. The mounting boss 21 includes a boss base body 23 having a bottom face bonded to the outer peripheral face of the case body and composed of a composite material of reinforcing fibers and thermosetting resin, and an insert 25 embedded in the boss base body 23, composed of metal, and having a screw hole 27 allowing the auxiliary machine 7 to be mounted at the top face thereof.

Description

  The present invention relates to a case such as a cylindrical fan case capable of attaching an accessory device such as an auxiliary machine on the outside, and a mounting boss for attaching the accessory device to the outside of the case.

  In recent years, in the field of aircraft engines, a composite material (FRP) of reinforcing fiber and thermosetting resin has been attracting attention as a lightweight and high-strength material, and a composite material of reinforcing fiber and thermosetting resin is a constituent material. Various developments have been made on a cylindrical fan case to which an auxiliary machine can be attached on the outside (see Patent Document 1). The contents of the fan case according to the prior art are as follows.

  The fan case according to the prior art includes a cylindrical case body, and the case body is made of a composite material of a reinforcing fiber such as carbon fiber and a thermosetting resin such as epoxy resin. In addition, an annular intermediate flange for attaching the auxiliary machine is integrally formed over the entire circumference (the entire circumference of the outer peripheral surface of the case body) on the intermediate side in the case axial direction on the outer peripheral surface of the case main body. The intermediate flange is made of a composite material of a reinforcing fiber such as carbon fiber and a thermosetting resin such as epoxy resin, and the intermediate flange has a mounting portion such as a mounting hole in which an auxiliary machine can be mounted. Yes.

US Published Patent No. 2008-0118683

  By the way, in order to increase the degree of freedom of the attachment position of the auxiliary machine in the case axial direction, it is necessary to increase the number of formation points (formation number) of the intermediate flange in the case axial direction. On the other hand, when the number of formation points of the intermediate flange in the case axial direction is increased, although the intermediate flange is made of a lightweight composite material, the intermediate flange may be integrally formed over the entire outer periphery of the case body. Thus, the total weight of all the intermediate flanges increases, making it difficult to reduce the weight of the fan case.

  That is, there is a problem that it is difficult to reduce the weight of the fan case while increasing the degree of freedom of the attachment position of the auxiliary machine in the case axial direction.

  Accordingly, an object of the present invention is to provide a case of a novel configuration that can solve the above-described problems.

  A first feature of the present invention is that in a cylindrical case (cylinder case) in which a composite material of a reinforcing fiber and a thermosetting resin is used as a constituent material and an accessory device can be attached to the outside, the reinforcing fiber and the thermosetting resin A cylindrical case body made of a composite material, and a mounting boss disposed on the outer peripheral surface of the case body for mounting the accessory device, the mounting boss having a bottom surface ( The back surface is bonded to the outer peripheral surface of the case body, and is composed of a boss base composed of a composite material of reinforcing fiber and thermosetting resin, embedded in the boss base, composed of metal, and on the top surface (front surface) And an insert provided with an attachment portion to which the accessory device can be attached.

  In the description of the specification and claims of the present application, the “case” is not only a fan case of an aircraft engine, but also a cylindrical case made of a composite material of a reinforcing fiber and a thermosetting resin. Is meant to include. Further, “provided” means that it is provided directly, or indirectly provided via another member, or formed.

  According to the first feature, the boss base is composed of a composite material of a reinforcing fiber and a thermosetting resin, the insert composed of metal is embedded in the top surface of the boss base, and the top surface of the insert is embedded. Since the attachment portion to which the attachment device can be attached is provided, it is possible to secure the attachment strength of the attachment device to the attachment boss and increase the number of locations in the case axial direction of the attachment boss. The increase in the total weight of all the mounting bosses can be sufficiently suppressed.

  A second feature of the present invention is a mounting boss for attaching an accessory to the outside of a case, a boss base composed of a composite material of a reinforcing fiber and a thermosetting resin, embedded in the boss base, The gist of the present invention is that it is made of metal and has an insert provided on the top surface (surface) with an attachment portion to which the accessory device can be attached.

  According to the 2nd characteristic, there exists an effect | action similar to the effect | action by a 1st characteristic.

  According to the present invention, the securing weight of the accessory device to the mounting boss is secured, and even if the mounting bosses are disposed in the case axial direction, the total weight of all the mounting bosses is increased. Since the increase can be sufficiently suppressed, the weight of the case can be sufficiently reduced while increasing the degree of freedom of the attachment position of the accessory device in the case axial direction.

FIG. 1A is a top view of FIG. 1B, and FIG. 1B is a cross-sectional view showing the main part of the fan case according to the embodiment of the present invention. 2A is a cross-sectional view of the mounting boss according to the embodiment of the present invention, FIG. 2B is a plan view of the insert of the mounting boss according to the embodiment of the present invention, and FIG. It is a front view of the insert of the mounting boss | hub which concerns on embodiment of this invention. FIG. 3 is an enlarged view of the arrow III in FIG. FIG. 4 is a schematic cross-sectional view of the aircraft engine.

  An embodiment of the present invention will be described with reference to FIGS. In the drawings, “FF” indicates the forward direction, and “FR” indicates the backward direction.

  As shown in FIG. 4, a cylindrical fan case 1 according to an embodiment of the present invention is used for an aircraft engine 3 and covers a plurality of fan blades 5 in the aircraft engine 3. The fan case 1 is made of a composite material (FRP) of reinforcing fibers and a thermosetting resin, and an auxiliary machine (an example of an accessory device) 7 can be attached to the outside. Hereinafter, the configuration and the like of the fan case 1 according to the embodiment of the present invention will be described in detail.

  As shown in FIG. 3, the fan case 1 includes a cylindrical case body 9, which includes a reinforcing fiber such as carbon fiber, aramid fiber, or glass fiber, an epoxy resin, a phenol resin, Or it is comprised by the composite material with thermosetting resins, such as a polyimide resin. Specifically, a mandrel (not shown) having a molding surface corresponding to the shape of the case body 9 is used, and a reinforcing fiber such as carbon fiber in which the molding surface of the mandrel is impregnated with a thermosetting resin such as an epoxy resin in advance. A woven fabric (not shown) or roving (not shown) is wound to form a molded body (not shown), and the molded body is heated to cure the thermosetting resin.

  An annular front flange 11 is integrally formed on the front peripheral edge of the case body 9, and the front flange 11 is attached to an engine cowl 13 disposed on the front side of the fan case 1 with a plurality of front joint bolts (not shown). Can be joined. An annular rear flange 15 is integrally formed on the rear periphery of the case body 9, and the rear flange 15 is attached to a rear case 17 disposed on the rear side of the fan case 1 with a plurality of rear joint bolts. They can be joined by (not shown).

  A plurality of mounting bosses 21 for mounting the auxiliary machine 7 by mounting bolts 19 are disposed on the outer peripheral surface of the case body 9, and the specific configuration of each mounting boss 21 is as follows. .

  As shown in FIGS. 1A and 1B and FIG. 2A, the mounting boss 21 includes a truncated cone-shaped boss base 23, and the bottom surface (back surface) of the boss base 23 is a case body. It is joined to the outer peripheral surface of 9 via adhesives, such as an epoxy-type adhesive agent. The boss base 23 is composed of a composite material of a reinforcing fiber such as carbon fiber, aramid fiber, or glass fiber and a thermosetting resin such as an epoxy resin, a phenol resin, or a polyimide resin. It has a laminated structure in which S is laminated in the thickness direction. The boss base 23 may have a pyramid shape or a cylindrical shape instead of the truncated cone shape.

  A pin-shaped insert 25 is embedded in the central portion of the mounting boss 21. The insert 25 is made of a metal such as stainless steel. Further, a screw hole 27 that can be screwed with the mounting bolt 19 is formed on the top surface (surface) of the insert 25, and this screw hole 27 serves as a mounting portion to which the auxiliary machine 7 can be mounted by the mounting bolt 19. It has the function of The mounting bolt 19 can be inserted into a through hole 7h formed in the mounting flange 7f of the auxiliary machine 7.

  As shown in FIGS. 2B and 2C, a taper portion 29 whose diameter increases toward the bottom surface side of the insert 25 is formed on the bottom surface side portion of the outer peripheral surface of the insert 25. It has a function as a retaining portion for retaining the boss base 23. Instead of forming the taper portion 29 on the bottom surface side portion of the outer peripheral surface of the insert 25, an annular flange as a retaining portion may be formed on the bottom surface side periphery of the insert 25.

  A pair of cutout portions 31 are formed symmetrically on the bottom surface side portion of the outer peripheral surface of the insert 25, and the pair of cutout portions 31 have a function as a rotation stop portion that performs rotation stop with respect to the boss base 23. ing. Instead of forming the notch 31 on the bottom surface side portion of the outer peripheral surface of the insert 25, the insert 25 has a prismatic shape (for example, a quadrangular prism shape, for example) so that a flat portion as a rotation stop portion is formed on the outer peripheral surface of the insert 25. ).

  As shown in FIGS. 1 (a) and 1 (b), an epoxy adhesive is provided on the outer peripheral surface of the case body 9 so that a plurality of circular covers 33 (only one shown) cover the corresponding mounting bosses 21. Each cover 33 is a composite material of a reinforcing fiber such as carbon fiber, aramid fiber, or glass fiber and a thermosetting resin such as epoxy resin, phenol resin, or polyimide resin. It is comprised by. A through hole 35 through which the mounting bolt 19 can pass is formed at the center of each cover 33.

  Then, the effect | action and effect of embodiment of this invention are demonstrated.

  The boss base 23 is made of a composite material of a reinforcing fiber such as carbon fiber and a thermosetting resin such as an epoxy resin, and an insert 25 made of a metal such as stainless steel is embedded in the top surface of the boss base 23. Since a screw hole 27 as a mounting portion to which the auxiliary machine 7 can be mounted is formed on the top surface of 25, the mounting boss 21 is secured to the mounting boss 21 with sufficient mounting strength with respect to the mounting boss 21. Even if the number of locations in the case axial direction (front-rear direction) is increased, an increase in the total weight of all the mounting bosses 21 can be sufficiently suppressed. In particular, since the boss base 23 is made of a composite material of a reinforcing fiber such as carbon fiber and a thermosetting resin such as an epoxy resin, compared to a case where the boss base 23 is made of a metal such as stainless steel, An increase in the total weight of all the mounting bosses 21 can be further suppressed.

  Since the taper portion 29 is formed as a retaining portion on the bottom surface side portion of the outer peripheral surface of the insert 25 and the pair of cutout portions 31 are formed on the bottom surface side portion of the outer peripheral surface of the insert 25 as a boss base. Thus, the bonding strength (embedding strength) of the insert 25 with respect to 23 can be sufficiently increased.

  Since the cover 33 is provided on the outer peripheral surface of the case body 9 so as to cover the attachment boss 21, the bonding strength (attachment strength) of the attachment boss 21 to the case body 9 can be sufficiently increased.

  Therefore, according to the embodiment of the present invention, even if the mounting strength of the auxiliary machine 7 with respect to the mounting boss 21 is sufficiently secured and the number of locations of the mounting boss 21 in the case axial direction is increased, all mounting is performed. Since the increase in the total weight of the boss 21 can be sufficiently suppressed, the weight of the fan case 1 can be sufficiently reduced while increasing the degree of freedom of the attachment position of the auxiliary machine 7 in the case axial direction.

  Further, since the bonding strength of the insert 25 to the boss base 23 and the bonding strength of the mounting boss 21 to the case body 9 can be sufficiently increased, the mounting state of the auxiliary machine 7 can be stabilized and The separation of the machine 7 can be reliably prevented.

  The present invention is not limited to the description of the above-described embodiment. For example, the idea applied to the fan case 1 can be implemented in various other modes, such as application to a cylindrical case other than the fan case 1. It is. Further, the scope of rights encompassed by the present invention is not limited to these embodiments.

DESCRIPTION OF SYMBOLS 1 Fan case 3 Aircraft engine 5 Fan blade 7 Auxiliary machine 7f Mounting flange 7h Through hole 9 Case main body S layer sheet | seat 11 Front flange 15 Rear flange 19 Mounting bolt 21 Mounting boss 23 Boss base | substrate 25 Insert 27 Screw hole (attachment part)
29 Tapered part (Retaining part)
31 Notch (rotation stop)
33 Cover 35 Through-hole

Claims (8)

In the cylindrical case where the composite material of reinforced fiber and thermosetting resin is used as the constituent material, and the attached device can be attached to the outside,
A cylindrical case body made of a composite material of reinforcing fibers and thermosetting resin;
A mounting boss disposed on the outer peripheral surface of the case main body for mounting the accessory device;
The mounting boss is
A boss base made of a composite material of a reinforcing fiber and a thermosetting resin, the bottom surface being bonded to the outer peripheral surface of the case body;
A case comprising: an insert embedded in the boss base, made of metal, and provided with an attachment portion on the top surface to which the accessory device can be attached.   The case according to claim 1, wherein a retaining portion for retaining the boss base is formed on an outer peripheral surface of the insert.   The case according to claim 1 or 2, wherein a rotation-stopping portion for stopping rotation with respect to the boss base is formed on an outer peripheral surface of the insert.   The cover provided with the outer peripheral surface of the said case main body so that the said boss | hub base | substrate was covered, and comprised with the composite material of the reinforced fiber and the thermosetting resin was comprised. A case according to any one of the claims.   The case according to any one of claims 1 to 4, wherein the case is used for an aircraft engine and covers a plurality of fan blades in the aircraft engine. In the mounting boss for mounting the accessory on the outside of the case,
A boss base composed of a composite material of reinforcing fibers and thermosetting resin;
An attachment boss, comprising: an insert embedded in the boss base, made of metal, and provided with an attachment portion on the top surface to which the accessory device can be attached.   The mounting boss according to claim 1, wherein a retaining portion for retaining the boss base is provided on an outer peripheral surface of the insert.   8. The mounting boss according to claim 6, wherein a rotation stopping portion for stopping rotation with respect to the boss base is provided on an outer peripheral surface of the insert. 9.

Images