JPH02136449A - Fitting structure of wall panel - Google Patents

Abstract

PURPOSE:To raise the efficiency of constructing operations by a method in which the vertical screw shaft of a regulating metal to be attached to wall panels is attached to a horizontal framework to be set on the outer face of a housing structure by touching it to the horizontal receiving piece of the horizontal framework. CONSTITUTION:A horizontal framework 2 to be set on the outer face of a housing structure is made up of frame panels below a frame 21 provided to the lower beam part L of the housing structure. The lower end of the lower wall panel P1 is temporarily set on the upside of the projected piece 14 of the framework 2, and the screw lever 29 projected from the wall panel P1 is temporarily clamped with a nut 36. The lower end 5a of the screw shaft 5 of a regulating metal 6 is contacted with the receiving piece 7 of the framework 2, during which period the shaft 5 is turned to adjust the height of the panel P1. The nut of the lever 29 is more clamped, the rising piece 9 of the framework 2 is held by a base piece 10 and a contact piece 32 to fix the lower part of the panel P1. The nut 36 is further clamped and the vertical piece 26 of the upper frame panel 24 is held by a contact piece 34 and a press 35 to fix the upper part of the panel P1.

Description

【発明の詳細な説明】 〔産業上の利用分野〕 本発明は家屋構造体の外面に壁パネルを精度よくかつ容
易に取付けうる壁パネルの取付構造に関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a wall panel mounting structure that allows wall panels to be mounted accurately and easily on the outer surface of a house structure.

〔従来の技術〕[Conventional technology]

壁、床、屋根などをパネルを用いて形成するいわゆるパ
ネル工法の家屋が普及している。このようなパネル工法
による家屋にあっては、パネルは、予め工場で生産され
るとともに、施工現場において家屋骨組体にボルト等の
固定金具を用いて取付けられる。Houses built using the so-called panel construction method, in which walls, floors, roofs, etc. are formed using panels, are becoming popular. In houses built using such panel construction methods, the panels are produced in advance at a factory and are attached to the house frame at the construction site using fixing fittings such as bolts.

又近年、家屋の外向き面に配される外壁用の壁パネルに
あっては、居住面積の増大、敷地の有効利用を計るため
、柱、梁などの外側に配されることが多い。In addition, in recent years, wall panels for external walls placed on the outward facing surfaces of houses are often placed on the outside of pillars, beams, etc. in order to increase the living area and make effective use of the site.

〔発明が解決しようとする！！Ｉｆｆ）このような外壁
用の壁パネルは、製作誤差、取付は誤差等によって家屋
の骨組体との接続に関して両者の接続端に位置ずれが生
じ昌くその修正に多大の手間を要する。[Invention tries to solve it! ! If) In such a wall panel for an exterior wall, due to manufacturing errors, installation errors, etc., the positional deviation occurs at the connecting end of the two when connected to the frame of the house, and it takes a lot of effort to correct this.

しかも外壁用の壁パネルは耐火材を用いて形成されてい
るため、重量が比較的重く、その移動は容易ではない。Furthermore, since the wall panels for the exterior walls are made of fireproof material, they are relatively heavy and difficult to move.

従って骨組体の外側に壁パネルを張出して取付ける場合
であっても、その取付けが容易にでき組付は精度を高め
うる構造のものの出現が要望されていた。Therefore, even when a wall panel is attached to the outside of a frame body by extending it, there has been a demand for a structure that can be easily attached and that can be assembled with high accuracy.

本発明は、壁パネルに垂直方向に調整可能な調整金具を
設けることを基本として、家屋構造体の外面に壁パネル
を精度よくかつ容易に取付けでき、しかも耐震性にも優
れる壁パネルの取付構造の提供を目的としている。The present invention is based on the provision of adjustment fittings that can be adjusted in the vertical direction on the wall panel, and the wall panel mounting structure allows the wall panel to be mounted accurately and easily on the outer surface of the house structure, and also has excellent earthquake resistance. The purpose is to provide

〔課題を解決するための手段〕[Means to solve the problem]

前記問題点を解決するため、本発明は、家屋構造体の外
向き面に、水平な受片の外縁に垂直に立上がる立上げ片
を有する横架構材を架設し、かつ前記立上げ片の内側で
垂下する基片に垂直なネジ穴を有するナツト部材を固着
した支持金物と、前記ネジ穴に螺合するネジ軸とからな
る調整金具を、前記基片を用いて前記外向き面に沿って
配した壁パネルの内向き面にかつネジ軸下端を前記受片
上面に当接させて取付けてなる壁パネルの取付構造であ
る。In order to solve the above-mentioned problems, the present invention erects on the outward facing surface of a house structure a horizontal frame member having a rising piece that stands up perpendicularly to the outer edge of a horizontal support piece, and An adjustment fitting consisting of a support metal fitting to which a nut member having a perpendicular screw hole is fixed to a base piece that hangs down on the inside, and a screw shaft that is screwed into the screw hole is attached along the outward surface using the base piece. This is a wall panel mounting structure in which the screw shaft is mounted on the inward facing surface of the wall panel arranged with the lower end of the screw shaft in contact with the upper surface of the receiving piece.

〔作用〕[Effect]

支持金物のネジ穴に螺入するネジ軸を、その下端を受片
の上面に当接させつつ螺旋回させることにより、取付具
は横架構材の受片上面に向かって近接し、該受片に当接
する。さらにネジ軸の螺旋回を続けることにより壁パネ
ルは取付具とともに上下に移動することができる。By spirally rotating the screw shaft that is screwed into the screw hole of the support piece with its lower end in contact with the upper surface of the receiver piece, the fixture approaches the upper surface of the receiver piece of the horizontal frame member, and comes into contact with. Further, by continuing the spiral rotation of the screw shaft, the wall panel can be moved up and down together with the fixture.

従って壁パネルの重量が大であってもその壁パネルをク
レーン等で保持することなく、取付位置の位置決めがで
き、壁パネルの組付作業が容易にかつその取付精度を高
めうる。Therefore, even if the wall panel is heavy, the mounting position can be determined without having to hold the wall panel with a crane or the like, making it possible to easily assemble the wall panel and improve its mounting accuracy.

又壁パネルは、ネジ軸を受片に常に当接させうるため、
壁パネルの重量を横架構材に担持させることができるた
め、従来の壁パネルのように、内面から水平に突出する
ボルトによって取付けていたものに比べて、地震等家屋
に横揺れが生じた場合であっても壁パネルにずれが生じ
ることがなく、耐震性においても優れる。In addition, since the wall panel allows the screw shaft to always be in contact with the receiving piece,
Because the weight of the wall panel can be carried by the horizontal structural members, compared to conventional wall panels that are attached using bolts that protrude horizontally from the inner surface, it is easier to handle when a house shakes due to an earthquake. However, the wall panels do not shift, and they have excellent earthquake resistance.

〔実施例〕〔Example〕

以下本発明の一実施例を図面に基づき説明する。 An embodiment of the present invention will be described below based on the drawings.

図において、本発明の壁パネルの取付は構造は、家屋構
造体Ａの外向き面に壁パネルＰを取付けるための構造で
ある。In the figure, the wall panel mounting structure of the present invention is a structure for mounting a wall panel P on the outward facing surface of a house structure A.

家屋構造体Ａは、本実施例では第５図に示す如く階下、
階上に広巾の開口部を有する２階建の家屋であって階上
の開口部Ｆは、第１図に示す如く該開口部Ｆの両側で立
上がる一対の柱ＨＳＨ間に下の梁材Ｌ１、上の梁材Ｌ２
の夫々の外向き面Ｂに配される下の壁パネルＰ１、上の
壁パネルＰ２の間に形成される。In this embodiment, the house structure A has a downstairs area, as shown in FIG.
It is a two-story house with a wide opening on the upper floor, and the opening F on the upper floor is located between a pair of columns HSH that stand up on both sides of the opening F, as shown in Figure 1. L1, upper beam material L2
It is formed between the lower wall panel P1 and the upper wall panel P2 arranged on the outward facing surface B of each.

下の梁材Ｌ１は、上フランジ、下フランジを具える断面
Ｉ形の型材であり、上、下のフランジの外側縁は前記柱
Ｈの外向き面より外面に突出している。The lower beam L1 is an I-shaped cross section that includes an upper flange and a lower flange, and the outer edges of the upper and lower flanges protrude outward from the outward facing surface of the column H.

下の梁材Ｌ１の外側には枠組体２１が設けられる。枠組
体２１は水平片と垂直片とからなる断面山形の枠材を、
向き合う枠材の各垂直片を向き合わせて矩形に枠組して
なり、枠組体２１の内部には縦向きの桟材２２を複数本
架は渡している。A frame body 21 is provided outside the lower beam L1. The frame body 21 is made of a frame member having a chevron-shaped cross section and consisting of a horizontal piece and a vertical piece.
The frame is made up of a rectangular frame with the vertical pieces of facing frame members facing each other, and a plurality of vertically oriented crosspieces 22 are passed inside the frame body 21.

枠組体２１は、前記桟材２２に一端が取付く一対の連結
片２３．２３の他端を下の梁材Ｌ１の上のフランジ及び
下のフランジに夫々接続することにより枠組体２１は下
の梁材Ｌ１からはみ出してその外側に、かつ垂直片を外
に向は取付け＃ＩＩ４ることにより、枠組体２１の下方
に位置する枠材が家屋構造体Ａの外向き面Ｂに架設され
る横架構材２を形成する。横架構材２は、枠材の前記水
平片が受片７を、又垂直片が受片７の前縁で立上がる立
上げ片９を形成する。The frame body 21 is constructed by connecting the other ends of the pair of connecting pieces 23 and 23, one end of which is attached to the beam 22, to the upper and lower flanges of the lower beam L1, respectively. By attaching the vertical piece #II4 to the outside of the beam L1 protruding from the beam L1, the frame member located below the frame body 21 is installed horizontally on the outward facing surface B of the house structure A. A frame member 2 is formed. In the horizontal frame member 2, the horizontal piece of the frame member forms a receiving piece 7, and the vertical piece forms a rising piece 9 rising from the front edge of the receiving piece 7.

又受片７の下面には、外方に向かってのび、上面が下の
壁パネルＰ１の下端を支持でき、支持することにより下
の壁パネルＰ１を仮置きしうる突出片１４を固定する。Further, a projecting piece 14 is fixed to the lower surface of the receiving piece 7, which extends outward, and whose upper surface can support the lower end of the lower wall panel P1, and by supporting it, the lower wall panel P1 can be temporarily placed.

前記枠組体２１の上の枠材２４は、水平片２５の前縁か
ら垂直片２６を下段し、該垂直片２６の外面と前記横架
構材２の立上げ片９の外面との間に下の壁パネルＰ１が
縦向きに配される。The frame member 24 on the frame body 21 has a vertical piece 26 lowered from the front edge of the horizontal piece 25, and a lower part between the outer surface of the vertical piece 26 and the outer surface of the rising piece 9 of the horizontal frame member 2. The wall panel P1 is arranged vertically.

下の壁パネルＰ１はモルタル等の耐火材を内部に装填し
た矩形板体であり、赤ｅｓｓａｏ匂゛ｉ＃−Ｏネジ部を
有する短杆２９を下の壁パネルＰ１の内向き面Ｃの各隅
部に位置させて内側に向かって突出する。The lower wall panel P1 is a rectangular plate filled with fireproof material such as mortar, and short rods 29 with red essao i#-O threads are connected to each of the inward facing surfaces C of the lower wall panel P1. It is located at the corner and protrudes inward.

下に位１する短杆２９には横架構材２に下の壁パネル２
の下部を係止させうる取付具３が取付けられる。The lower wall panel 2 is attached to the horizontal structural member 2 on the short rod 29 located at the bottom.
A fitting 3 is attached to which the lower part of the holder can be locked.

取付具３は、前記横架構材２の立上げ片９を挟着する支
持金物４と、該支持金物４に取付きかつ支持金物４とも
に下の壁パネルＰ１の上下位置を調整しうるネジ軸５と
を具える調節金具６を含む。The fixture 3 includes a support metal piece 4 that clamps the upright piece 9 of the horizontal frame member 2, and a screw shaft that is attached to the support metal piece 4 and that can adjust the vertical position of the wall panel P1 below the support metal piece 4. 5, and an adjustment fitting 6 comprising:

支持金物４は、前記立上げ片９の内側で垂下するととも
に下側の短杆２９．２９を夫々挿通する二つの透孔３０
．３０を具える横長矩形の基片１０と、該基片１０内側
面に取付き垂直なネジ穴１１を有するナツト部材１２と
を有し、該ネジ穴１２には、下端面１２Ａが平坦に形成
されたネジ軸５が螺入される。前記支持金物４と該ネジ
軸５とによって調節金具６を形成する。The support hardware 4 has two through holes 30 that hang down inside the upright piece 9 and pass through the lower short rods 29 and 29, respectively.
．． A nut member 12 is attached to the inner surface of the base piece 10 and has a vertical screw hole 11, and the screw hole 12 has a flat lower end surface 12A. The screw shaft 5 is screwed in. The support metal fitting 4 and the screw shaft 5 form an adjustment metal fitting 6.

又本実施例では調節金具６の外側にかつ立上げ片９と略
同寸の厚みををし短杆２９挿通用の穴を中心に設けたデ
スタンスピース３１と、前記立上げ片９の外面に当接す
る当接面３２ａを有する当接片３３とが配され、前記デ
スタンスピース３１、当接片３３は調節金具６とともに
、前記取付具４を形成する。In addition, in this embodiment, a distance piece 31 is provided on the outside of the adjustment fitting 6, has a thickness approximately the same as that of the upright piece 9, and is provided with a hole for inserting the short rod 29 in the center, and an outer surface of the upright piece 9. A contact piece 33 having an abutting surface 32a that comes into contact with is disposed, and the distance piece 31 and the abutting piece 33 together with the adjustment fitting 6 form the mounting fixture 4.

当接片３３は、中心に前記短杆２９が貫通する透孔を設
けるとともに、その内側に向く面にゴムシート３３を添
着することにより、前記当接面３２ａのＮａ力を高めて
いる。The abutment piece 33 has a through hole in the center through which the short rod 29 passes, and a rubber sheet 33 is attached to the inward surface of the abutment piece 33 to increase the Na force of the abutment surface 32a.

前記ネジ軸５を、下方に向かって螺進させることによっ
て、その下端面５ａが前記横架横材２の受片７と当接し
、父上の壁パネルＰＬは受片７の前記当接によ！ｌ−１
＋横架構材２によって支持されるとともに、ネジ軸５を
上下動させることによって下の壁パネルＰ１の高さ位置
を調節することができる。さらに短杆２９に、基片ｌＯ
を、デスタンスピース３１、当接片３２を介在させて嵌
入しかつ立上げ片９を基片１０によって挟持させつつナ
ツト締めすることにより、下の壁パネルＰ１は、前記ネ
ジ軸５によって調節された位置を保持して横架構材２に
固定することができろ。By screwing the screw shaft 5 downward, its lower end surface 5a comes into contact with the receiving piece 7 of the horizontal member 2, and the father's wall panel PL is caused by the contact of the receiving piece 7. ! l-1
+ It is supported by the horizontal structural member 2, and the height position of the lower wall panel P1 can be adjusted by moving the screw shaft 5 up and down. Furthermore, on the short rod 29, the base piece lO
is inserted through the distance piece 31 and the abutment piece 32, and is tightened with a nut while the upright piece 9 is held between the base piece 10, so that the lower wall panel P1 can be adjusted by the screw shaft 5. It should be possible to maintain the position and fix it to the horizontal frame member 2.

下の壁パネルＰ１の上部には、上の枠材２４の短杆２９
に挿入される係止具３３が設けられる。At the top of the lower wall panel P1, there are short rods 29 of the upper frame material 24.
A locking tool 33 is provided which is inserted into the.

係止具３３は上の枠材２４の垂直片２６の外側に位置し
前記取付具３の当接片３２と同様に形成された当接片３
４と、前記垂直片２６の内側に配され２字状に折れ曲が
る押さえ片３５とを具える。The locking tool 33 is a contact piece 3 located outside the vertical piece 26 of the upper frame member 24 and formed similarly to the contact piece 32 of the fixture 3.
4, and a presser piece 35 arranged inside the vertical piece 26 and bent into a double shape.

然して下の壁パネルＰＩは、クレーン等を用いて下の壁
パネルＰ１の下端を前記突出片１４の上面に仮置し、横
架構材２の外面に沿って立て掛けるとともに、核上の壁
パネルＰ１の上部はナツト３６の仮締めによって、上の
枠材２４の垂直片２６の内、外面を当接片３２、係止具
３３によってガイドし、下の壁パネルＰＩの倒れを防ぐ
、然る後、ネジ軸５の下端面５ａを受片７に当接させつ
つネジ軸５を螺旋回させ、下の壁パネルＰ１の高さを調
整するとともに短杆２９のナツトを締め上げ、横架構材
２の立上げ片９を基片１０と当接片２５とによって決着
し、下の壁パネルＰ１の下部を固定する。However, the lower wall panel PI is constructed by temporarily placing the lower end of the lower wall panel P1 on the upper surface of the protruding piece 14 using a crane or the like, and leaning it against the outer surface of the horizontal frame member 2, and also attaching the lower wall panel P1 on the core. By temporarily tightening the nuts 36, the inner and outer surfaces of the vertical pieces 26 of the upper frame member 24 are guided by the contact pieces 32 and the locking tools 33 to prevent the lower wall panel PI from falling. , the screw shaft 5 is spirally rotated while the lower end surface 5a of the screw shaft 5 is brought into contact with the receiving piece 7, the height of the lower wall panel P1 is adjusted, and the nuts of the short rods 29 are tightened, and the horizontal structural member 2 The rising piece 9 is fixed by the base piece 10 and the abutting piece 25, and the lower part of the lower wall panel P1 is fixed.

下の壁パネルＰ２の上部は、係止具３３をナツト３６の
本締めすることにより、上の枠材２４の垂直片２６を当
接片３４、押え片３５により挟着し固定する。The upper part of the lower wall panel P2 is fixed by fully tightening the locking tool 33 with the nut 36, so that the vertical piece 26 of the upper frame member 24 is clamped and fixed by the abutting piece 34 and the holding piece 35.

このように下の壁パネルＰＩは前記構成の調節金具６を
有することにより、高さ位置の調整が容易となりかつナ
ツト部材１２を介して横架構材２に支持されているため
家屋構造体Ａに地震など横揺れが生じた場合であっても
位置ずれすることがない。In this way, the lower wall panel PI has the adjustment fitting 6 having the above-mentioned configuration, so that the height position can be easily adjusted, and since it is supported by the horizontal frame member 2 via the nut member 12, it can be attached to the house structure A. Even in the event of horizontal shaking such as an earthquake, it will not shift position.

上の壁パネルＰ２を取付ける横架構材２Ａは、前記構成
の受片７と立上げ片９とを有し、又該横架構材２人は、
上の梁材Ｌ２の下部にＬ字状をなす連結片４１を介して
接続される。The horizontal frame member 2A to which the upper wall panel P2 is attached has the receiving piece 7 and the rising piece 9 configured as described above, and the two horizontal frame members are:
It is connected to the lower part of the upper beam L2 via an L-shaped connecting piece 41.

上の壁パネルＰ２は前記下の壁パネルＰ１と同様に、そ
の下部から突出する短杆２９に前記取付具３と同じ構成
の取付具３Ａが設けられ、従って該取付具３Ａより上の
壁パネルＰ２は高さを調整することができ、父上の壁パ
ネルＰ２を横架構材２Ａに支持させうる。Similar to the lower wall panel P1, the upper wall panel P2 is provided with a fixture 3A having the same configuration as the fixture 3 on the short rod 29 protruding from its lower part, and therefore the wall panel above the fixture 3A is The height of P2 can be adjusted, and the father's wall panel P2 can be supported by the horizontal frame member 2A.

なお本実施例では上の壁パネルＰ２の上部は、上の梁材
Ｌ２上部から外にのびるＬ字状の連結金具４２の立片４
３に短杆２９が直接ナツト締めにより固定されている。In this embodiment, the upper part of the upper wall panel P2 is connected to the vertical piece 4 of the L-shaped connecting fitting 42 extending outward from the upper part of the upper beam L2.
A short rod 29 is directly fixed to 3 by tightening a nut.

なお上の壁パネルＰ２は仮置きすることがないため、横
架構材２Ａには突出片は設けていない。Note that since the upper wall panel P2 is not temporarily placed, no protruding piece is provided on the horizontal frame member 2A.

なお本発明の壁パネルの取付構造は、開口部を設けるこ
となく床体近傍から天井付近にのびる丈長の壁パネルの
取付けにも採用することができる。Note that the wall panel mounting structure of the present invention can also be employed for mounting a long wall panel that extends from near the floor to near the ceiling without providing an opening.

〔発明の効果〕〔Effect of the invention〕

叙上の如く本発明の壁パネルの取付構造は、家屋構造体
の外向き面に架設される横架構材に、壁パネルに取付く
取付具の垂直なネジ軸を前記横架構材の水平な受片に当
接させて取付ける構造であるため、壁パネルの高さ調節
が容易となり施工能率を高めうる。又壁パネルはネジ軸
を介して横架構材に支持されているため、家屋構造体に
地震等によって横揺れが発生した場合であっても壁パネ
ルにずれが生じることがなく耐震性を向上しうる。As described above, the wall panel mounting structure of the present invention is such that the vertical screw shaft of the fixture to be attached to the wall panel is connected to the horizontal frame member installed on the outward facing surface of the house structure, so that the vertical screw shaft of the fixture to be attached to the wall panel is aligned with the horizontal frame member. Since the structure is such that it is attached in contact with a receiving piece, the height of the wall panel can be easily adjusted and construction efficiency can be increased. In addition, since the wall panels are supported by the horizontal structural members via screw shafts, even if the house structure experiences lateral shaking due to an earthquake, the wall panels will not shift, improving earthquake resistance. sell.

【図面の簡単な説明】[Brief explanation of the drawing]

第１図は本発明の一実施例を示す斜視図、第２図は下の
壁パネルの取付けを例示する断面図、第３図は取付具を
示す分解斜視図、第４図は上の壁パネルの取付けを例示
する断面図、第５図は本発明の構造を用いた家屋構造体
の一例を示す斜視図である。 ２．２Ａ・・・・・横架構材、　３．３Ａ・−・取付具
、４・−・支持金物、　５・・−・ネジ軸、　６−・−
・調節金具、７−・・受片、　　９・−・立上げ片、　
　１０−・基片、１１・−・・・ネジ穴、　　１２・・
−サット部材、Ａ・−・・・家屋構造体、　Ｂ・・・−
外向き面、Ｃ−ｍ−・内向き面、　Ｐ、Ｐｌ、Ｐ２・−
壁パネル。 特許出願人　　　　ナシッナル住宅産業株式会社代理人
　弁理士　　苗　　村　　　　　　　　正第４段 第５図Fig. 1 is a perspective view showing an embodiment of the present invention, Fig. 2 is a cross-sectional view illustrating the installation of the lower wall panel, Fig. 3 is an exploded perspective view showing the fixture, and Fig. 4 is the upper wall. FIG. 5 is a sectional view illustrating the installation of panels, and FIG. 5 is a perspective view illustrating an example of a house structure using the structure of the present invention. 2.2A...Horizontal structural member, 3.3A...Mounting tool, 4...Support hardware, 5...Screw shaft, 6-...
・Adjustment bracket, 7--Socket piece, 9--Rising piece,
10--Base piece, 11--Screw hole, 12--
-Sat member, A...house structure, B...-
Outward facing surface, C-m-・Inward facing surface, P, Pl, P2・-
wall panel. Patent applicant Nashinal Housing Industry Co., Ltd. Agent Patent attorney Tadashi Naemura 4th paragraph Figure 5

Claims (1)

【特許請求の範囲】[Claims] １　家屋構造体の外向き面に、水平な受片の外縁に垂直
に立上がる立上げ片を有する横架構材を架設し、かつ前
記立上げ片の内側で垂下する基片に垂直なネジ穴を有す
るナット部材を固着した支持金物と、前記ネジ穴に螺合
するネジ軸とからなる調整金具を、前記基片を用いて前
記外向き面に沿って配した壁パネルの内向き面にかつネ
ジ軸下端を前記受片上面に当接させて取付けてなる壁パ
ネルの取付構造。1. On the outward facing surface of the house structure, a horizontal frame member having a standing piece that stands up perpendicularly to the outer edge of a horizontal support piece is erected, and a screw hole that is perpendicular to the base piece that hangs down inside the standing piece is installed. An adjustment fitting consisting of a supporting metal fitting having a nut member fixed thereto and a screw shaft screwed into the screw hole is attached to the inward facing surface of the wall panel arranged along the outward facing surface using the base piece. A wall panel mounting structure in which the lower end of the screw shaft is mounted in contact with the upper surface of the receiving piece.