JP4133779B2

JP4133779B2 - Hatch switchgear

Info

Publication number: JP4133779B2
Application number: JP2003407759A
Authority: JP
Inventors: 一男三井田
Original assignee: 株式会社東京エネシス
Priority date: 2003-12-05
Filing date: 2003-12-05
Publication date: 2008-08-13
Anticipated expiration: 2023-12-05
Also published as: JP2005163492A

Description

この発明は、原子力発電所等の各種の躯体の床面の開口するハッチを開閉するためのハッチの開閉装置に関する。 The present invention relates to a hatch opening and closing device for opening and closing a hatch that opens on the floor surface of various enclosures such as nuclear power plants.

一般に、原子力発電所の１階の床部には、ハッチが形成されている。このハッチは、地下に設けられた各階に対して物品を搬出入するためのものであり、床部を上下方向に貫通する貫通孔として形成されている。 In general, a hatch is formed on the floor of the first floor of a nuclear power plant. This hatch is for carrying in and out articles to and from each floor provided in the basement, and is formed as a through hole penetrating the floor portion in the vertical direction.

通常、ハッチは、蓋体によって開閉されるようになっている。例えば、特許文献１に記載のものにおいては、蓋体の一端部が水平な軸線を有するヒンジをを介してハッチの内周面又はハッチ近傍の躯体に閉位置と開位置との間を回動可能に連結されている。蓋体は、閉時にはほぼ水平な状態に回動してハッチの内周面に嵌合する。これによって、ハッチを閉じる。一方、開時には他端部が鉛直方向下方に位置するように閉位置からほぼ９０°下方へ回動する。これによって、ハッチを開く。 Usually, the hatch is opened and closed by a lid. For example, in the thing of patent document 1, one end part of a cover body rotates between a closed position and an open position to the inner peripheral surface of a hatch, or the housing | casing of the hatch vicinity via the hinge which has a horizontal axis line. Connected as possible. When the lid is closed, the lid rotates in a substantially horizontal state and is fitted to the inner peripheral surface of the hatch. This closes the hatch. On the other hand, at the time of opening, the other end portion is rotated approximately 90 ° downward from the closed position so that the other end portion is positioned vertically downward. This opens the hatch.

実開平６―８２５９９号公報Japanese Utility Model Publication No. 6-82599

上記特許文献１に記載のハッチの開閉装置においては、ハッチの開閉時に扉全体がその一端部を中心として回動する。その結果、蓋体の他端部は、蓋体の一端部から他端部までの長さを半径とする円周上を移動する。このため、蓋体の開閉に大きな空間を必要とするという問題があった。 In the hatch opening and closing device described in Patent Document 1, the entire door rotates around its one end when the hatch is opened and closed. As a result, the other end of the lid moves on a circumference having a radius from one end to the other end of the lid. For this reason, there was a problem that a large space was required for opening and closing the lid.

この発明は、上記の問題を解決するために、躯体の床面に開口する平面視矩形状をなすハッチを開閉するためのハッチの開閉装置において、上記躯体の上記ハッチの第１の辺に沿う部位に当該第１の辺と平行である水平な第１回動軸線を中心として基端部が上下方向へ回動可能に設けられ、先端部が閉位置とこの閉位置より上方に位置する開位置との間を回動変位する回動アームと、上記ハッチの開口部のうちの上記第１の辺側に位置する一端部と上記第１の辺と平行な第２の辺側に位置する他端部とをそれぞれ開閉し、互いに隣接する一端部どうしが上記第１回動軸線と平行な第２回動軸線を中心として回動可能に連結された第１及び第２蓋体とを備え、上記回動アームの先端部が上記第１蓋体に固定され、
上記第１蓋体と上記第２蓋体とが、上記回動アームの上記閉位置と上記開位置との間の回動に伴って展開位置と折畳位置との間を変位させられ、上記第１及び第２蓋体が、上記展開位置に位置しているときにはいずれもほぼ水平な状態になって上記ハッチの一端部と他端部とをそれぞれ閉じ、上記折畳位置に位置しているときにいずれもはほぼ上下に起立した状態で上記ハッチから上方へ離間して上記ハッチの一端部と他端部とをそれぞれ開くことを特徴としている。
この場合、上記ハッチの内部の上記第１及び第２の辺と直交する第３及び第４の各辺に当該第３及び第４の各辺に沿ってそれぞれ設けられたガイド部をさらに備え、上記第２蓋体が上記展開位置とこの展開位置から上記折畳位置側へ向かって所定の距離だけ離れた位置との間に位置しているときには、上記第２蓋体の他端部の上記第２の辺に沿う方向における両側部が上記ガイド部によって上記第３及び第４の各辺に沿う方向へそれぞれ移動可能に支持されていることが望ましい。上記第１回動軸線が、上記第２回動軸線より上側に配置され、上記第２蓋体が上記展開位置近傍の所定の範囲に位置しているときには、上記第２蓋体の上記他端部が上記展開位置に位置しているときの同端部より上記第２の辺側に位置し、上記第２蓋体が上記展開位置に位置しているときには、上記第２蓋体の他端部と上記第２の辺との間に隙間が形成されており、上記躯体の上記ハッチの第２の辺に沿う部位に、第１カバーの基端部が上記第１及び第２回動軸線と平行な第３回動軸線を中心としてカバー位置と逃げ位置との間を回動可能に設けられ、上記第２蓋体と上記第１カバーとの間には、少なくとも上記第２蓋体の他端部が上記第１カバーの先端部より上記第２の辺側に位置しているときに、上記第１カバーを上記カバー位置から上記逃げ位置に回動させる第１回動手段が設けられ、上記第１カバーは、上記カバー位置に位置しているときには、上記第２の辺に沿う方向における両側部が上記第３及び第４の各辺に隣接する上記躯体の床面上に載置されるとともに、先端部が第２蓋体の上面に載置されて上記第２の辺と上記第２蓋体との間に形成される隙間を遮蔽し、上記逃げ位置に位置しているときには、上記第１カバーの先端部が上記第２蓋体から上方に離間していることが望ましい。上記第１カバーの先端部の上記第２の辺に沿う方向における両側部には、上記第２蓋体側へ向かって延び出す突出部がそれぞれ設けられ、各突出部と対向する上記第２蓋体の両側部には、上記第１カバーが上記カバー位置に位置したときに上記突出部が嵌り込む切欠き部が設けられ、上記突出部の先端面と上記切欠き部に臨む上記第２蓋体の他端面との間に隙間が形成されており、各突出部と対向する上記第２蓋体の他端部の両側部には、第２カバーの基端部が上記第１〜第３回動軸線と平行な第４回動軸線を中心として遮蔽位置と待機位置との間をそれぞれ回動可能に設けられ、上記第２蓋体には、上記第２蓋体の上記折畳位置側から上記展開位置側への変位に伴って少なくとも上記第２カバーの先端部が上記第１カバーの先端部に対して所定距離だけ上記第１の辺側に位置している状態から上記第１カバーの先端部を通過して上記第２の辺側に移動した状態までの所定の範囲において上記第２カバーを上記待機位置に位置させる第２回動手段が設けられており、上記第２カバーは、上記遮蔽位置に位置しているときには、先端部が上記第１カバーの突出部の上面に載置されて上記第２蓋体と上記突出部との間の隙間を遮蔽し、上記待機位置に位置しているときには、上記第２蓋体の上記折畳位置側から上記展開位置側への移動に伴って上記第２カバーの先端部の下側に上記第１カバーの先端部が入り込むように、上方へ回動させられていることが望ましい。 In order to solve the above problems, the present invention provides a hatch opening and closing device for opening and closing a hatch having a rectangular shape in plan view that opens to the floor surface of the casing, and is along the first side of the hatch of the casing. A base end portion is provided to be pivotable in a vertical direction around a horizontal first rotation axis parallel to the first side, and a distal end portion is opened at a closed position and above the closed position. A pivot arm that pivots and displaces between positions, one end located on the first side of the opening of the hatch, and a second side parallel to the first side. The first and second lids each open and close the other end, and are connected to each other so as to be rotatable about a second rotation axis parallel to the first rotation axis. The tip of the pivot arm is fixed to the first lid,
The first lid and the second lid are displaced between a deployed position and a folded position in accordance with a rotation between the closed position and the open position of the rotation arm, When the first and second lids are located at the unfolded position, both are substantially horizontal and close one end and the other end of the hatch, and are located at the folding position. In some cases, each of them is characterized in that one end portion and the other end portion of the hatch are opened while being spaced upward from the hatch while standing up and down substantially.
In this case, each of the third and fourth sides orthogonal to the first and second sides inside the hatch further includes guide portions provided along the third and fourth sides, respectively. When the second lid is located between the unfolded position and a position away from the unfolded position toward the folding position by a predetermined distance, the other end of the second lid is It is desirable that both side portions in the direction along the second side are supported by the guide portion so as to be movable in directions along the third and fourth sides. When the first rotation axis is located above the second rotation axis and the second lid is located in a predetermined range near the unfolded position, the other end of the second lid When the second lid is located at the deployed position, the other end of the second lid is located closer to the second side than the same end when the portion is located at the deployed position. A gap is formed between the first side and the second side, and the base end portion of the first cover is located along the second side of the hatch of the housing, and the first and second rotation axes. Between a cover position and a relief position, with a third rotation axis parallel to the center being pivotable, and at least between the second lid and the first cover. When the other end is positioned on the second side from the tip of the first cover, the first cover is moved upward from the cover position. First rotating means for rotating to the escape position is provided, and when the first cover is located at the cover position, both side portions in the direction along the second side are the third and fourth sides. It is placed on the floor surface of the casing adjacent to each side, and the tip is placed on the upper surface of the second lid and formed between the second side and the second lid. When the gap is shielded and positioned at the escape position, it is desirable that the tip of the first cover is spaced upward from the second lid. Protrusions extending toward the second lid are provided on both sides in the direction along the second side of the tip of the first cover, and the second lid facing the projections. A notch portion into which the protruding portion is fitted when the first cover is located at the cover position is provided on both side portions of the first lid, and the second lid body faces the front end surface of the protruding portion and the notched portion. A gap is formed between the other end surface of the second cover body, and a base end portion of the second cover is disposed on both sides of the other end portion of the second cover body facing each projecting portion. It is provided so as to be able to rotate between a shielding position and a standby position around a fourth rotation axis parallel to the movement axis, and the second lid is provided on the folding position side of the second lid. At least the distal end portion of the second cover is moved relative to the distal end portion of the first cover along with the displacement toward the deployment position. The second cover is placed in the standby state within a predetermined range from a state where it is located on the first side by a fixed distance to a state where it has passed through the tip of the first cover and moved to the second side. When the second cover is located at the shielding position, a tip end portion is placed on the upper surface of the projecting portion of the first cover and the second cover is located at the position. When the gap between the two lids and the projecting portion is shielded and is located at the standby position, the second lid is moved along the movement from the folding position side to the unfolded position side. It is desirable that the first cover is pivoted upward so that the tip of the first cover enters the lower side of the tip of the two covers.

上記特徴構成を有するこの発明によれば、回動アームを閉位置と開位置との間において回動させたとき、第１及び第２蓋体は、第２回動軸線を中心として互いに回動可能であるから、二つ折り状態になって変位する。したがって、蓋体全体がその一端部を中心として回動する場合に比して、第１、第２蓋体を開くときに要する空間を狭くすることができる。 According to the present invention having the above-described characteristic configuration, when the pivot arm is pivoted between the closed position and the open position, the first and second lid bodies pivot with respect to each other about the second pivot axis. Since it is possible, it is displaced in a folded state. Therefore, the space required when opening the first and second lids can be reduced as compared with the case where the entire lid is rotated about its one end.

以下、この発明を実施するための最良の形態を、図１〜図１３を参照して説明する。
まず、この発明に係るハッチの開閉装置１が開閉すべきハッチＨについて説明すると、ハッチＨは、原子力発電所、その他の躯体（図示せず）の床スラブＳを上下に貫通する貫通孔として形成されている。ハッチＨの断面形状は、図１における左右方向（以下、左右方向と称する。）の長さが図１における上下方向（以下、前後方向と称する）の長さより長い長方形になっている。ハッチＨの床面Ｓａ側の開口部には、大径孔部Ｈａが形成されている。この大径孔部Ｈａが形成されることにより、ハッチＨの内周面に上方を向く支持面Ｈｂが形成されている。支持面Ｈｂは、ハッチＨの内周面に沿って環状に形成されている。床面Ｓａには、ハッチＨの上端開口部に沿って環状に延びるライナーＬが設けられている。 The best mode for carrying out the present invention will be described below with reference to FIGS.
First, a hatch H to be opened and closed by the hatch opening and closing device 1 according to the present invention will be described. The hatch H is formed as a through hole that vertically penetrates a floor slab S of a nuclear power plant or other enclosure (not shown). Has been. The cross-sectional shape of the hatch H is a rectangle in which the length in the left-right direction (hereinafter referred to as the left-right direction) in FIG. 1 is longer than the length in the up-down direction (hereinafter referred to as the front-rear direction) in FIG. A large-diameter hole Ha is formed in the opening of the hatch H on the floor surface Sa side. By forming the large-diameter hole portion Ha, a support surface Hb facing upward is formed on the inner peripheral surface of the hatch H. The support surface Hb is formed in an annular shape along the inner peripheral surface of the hatch H. The floor surface Sa is provided with a liner L that extends annularly along the upper end opening of the hatch H.

次に、この発明に係るハッチの開閉装置１について説明すると、開閉装置１はハッチＨの上端開口部、つまり大径孔部Ｈａを開閉するためのものであり、ハッチＨの内周面を形成する四つの辺のうちの前側に位置する第１の辺Ｈ１に隣接する床面Ｓａには、フレーム２が設けられている。このフレーム２には、第１の辺Ｈ１と平行な駆動軸３が回転可能に支持されている。この駆動軸３の軸線が第１回動軸線Ｌ１になっている。駆動軸３は、モータ４等の回転駆動源か、ハンドル５により手動で回転されるようになっている。駆動軸３をモータ４によって回転させるか、手動によって回転させるかの切り替えは、クラッチレバー６によって行われる。クラッチレバー６を図１に示す第１切り替え位置に位置させると、駆動軸３がモータ４によって回転駆動され、クラッチレバー６を第１切り替え位置から図１の時計方向へほぼ６０°程度回動させて第２切り替え位置に位置させると、駆動軸３が手動で回転駆動される。 Next, the hatch opening and closing device 1 according to the present invention will be described. The opening and closing device 1 is for opening and closing the upper end opening of the hatch H, that is, the large-diameter hole Ha, and forms the inner peripheral surface of the hatch H. A frame 2 is provided on the floor surface Sa adjacent to the first side H1 located on the front side of the four sides. A drive shaft 3 parallel to the first side H1 is rotatably supported by the frame 2. The axis of the drive shaft 3 is the first rotation axis L1. The drive shaft 3 is manually rotated by a rotational drive source such as a motor 4 or a handle 5. Switching between driving shaft 3 by motor 4 or manual rotation is performed by clutch lever 6. When the clutch lever 6 is positioned at the first switching position shown in FIG. 1, the drive shaft 3 is rotationally driven by the motor 4, and the clutch lever 6 is rotated from the first switching position clockwise by about 60 ° in FIG. When the second switching position is established, the drive shaft 3 is manually rotated.

駆動軸３には、回動アーム７の基端部が固定されている。回動アーム７は、モータ４又は手動により駆動軸３を介して回動駆動される。回動アーム７の回動範囲は、図１、図３及び図６に示す閉位置と、この閉位置から図３において半時計方向へほぼ９０°回動した図８に示す開位置との間に規制されている。回動アーム７は、基端部が駆動軸３に回転不能に連結された主部７ａと、この主部７ａの先端部に一体に設けられ、主部７ａに対して直交する方向に突出する突出部７ｂとを有している。回動アーム７が閉位置に位置しているとき、主部７ａは駆動軸３側からハッチＨ側へ向かってほぼ水平に延び、突出部７ｂは主部７ａからほぼ鉛直下方に突出している。したがって、回動アーム７が開位置に回動すると、主部７ａは、駆動軸３からほぼ鉛直上方に延び、突出部７ｂは主部７ａの上端部からハッチＨ側へ向かってほぼ水平に突出する。図３及び図８に示すように、回動アーム７が開位置に回動したとき、突出部７ｂの先端部は、ハッチＨの第１の辺Ｈ１に対して水平方向前方へ若干離間している。 A base end portion of the rotation arm 7 is fixed to the drive shaft 3. The rotating arm 7 is rotationally driven via the drive shaft 3 by the motor 4 or manually. The pivoting range of the pivoting arm 7 is between the closed position shown in FIGS. 1, 3 and 6 and the open position shown in FIG. 8 which is rotated from the closed position by approximately 90 ° counterclockwise in FIG. Is regulated. The pivot arm 7 is provided integrally with a main portion 7a whose base end portion is non-rotatably connected to the drive shaft 3 and a distal end portion of the main portion 7a, and protrudes in a direction perpendicular to the main portion 7a. And a protruding portion 7b. When the rotating arm 7 is in the closed position, the main portion 7a extends substantially horizontally from the drive shaft 3 side to the hatch H side, and the protruding portion 7b protrudes substantially vertically downward from the main portion 7a. Therefore, when the rotating arm 7 is rotated to the open position, the main portion 7a extends substantially vertically upward from the drive shaft 3, and the protruding portion 7b protrudes substantially horizontally from the upper end portion of the main portion 7a toward the hatch H side. To do. As shown in FIGS. 3 and 8, when the pivot arm 7 is pivoted to the open position, the tip of the projecting portion 7 b is slightly spaced forward from the first side H <b> 1 of the hatch H in the horizontal direction. Yes.

ハッチＨの大径孔部Ｈａは、第１の辺Ｈ１側に位置する前端部が第１蓋体８によって開閉され、第１の辺と平行な第２の辺側に位置する後端部が第２蓋体９によって開閉されるようになっている。 The large-diameter hole Ha of the hatch H has a front end located on the first side H1 side opened and closed by the first lid 8, and a rear end located on the second side parallel to the first side. The second lid 9 is opened and closed.

第１蓋体８は、図１〜図４に示すように、上板部８ａと、この上板部８ａの下面に固定された補強部８ｂとを有している。上板部８ａは、左右方向の長さが前後方向の長さより長い長方形の平板からなるものであり、左右方向の長さは、大径孔部Ｈａの左右方向の長さより長くなっている。上板部８ａの上面には、回動アーム７の突出部７ｂの先端部が固定されている。したがって、回動アーム７が回動すると、それに応じて第１蓋体８及び上板部８ａが駆動軸３を中心として回動変位する。上板部８ａは、回動アーム７が閉位置に位置しているときには、水平な状態になっている。このときの第１蓋体８の位置が展開位置である。第１蓋体８が展開位置に位置しているときには、上板部８ａの前端部及び左右両側部がライナーＬを介して床面Ｓａの第１、第３、第４の各辺Ｈ１，Ｈ３，Ｈ４に沿う部分に載置されている。この結果、大径孔部Ｈａの前側の端部が、第１蓋体８の上板部８ａによって閉じられている。上板部８ａは、回動アーム７が開位置に位置しているときには、後端部を上側に位置させた状態でほぼ鉛直に起立している。このときの第１蓋体８の位置が折畳位置である。 1-4, the 1st cover body 8 has the upper board part 8a and the reinforcement part 8b fixed to the lower surface of this upper board part 8a. The upper plate portion 8a is a rectangular flat plate whose length in the left-right direction is longer than the length in the front-rear direction, and the length in the left-right direction is longer than the length in the left-right direction of the large-diameter hole Ha. On the upper surface of the upper plate portion 8a, the tip of the protruding portion 7b of the rotating arm 7 is fixed. Therefore, when the turning arm 7 is turned, the first lid 8 and the upper plate portion 8a are turned and displaced about the drive shaft 3 accordingly. The upper plate portion 8a is in a horizontal state when the rotating arm 7 is located at the closed position. The position of the first lid 8 at this time is the deployed position. When the first lid body 8 is located at the unfolded position, the front end portion and the left and right side portions of the upper plate portion 8a are connected to the first, third, and fourth sides H1, H3 of the floor surface Sa via the liner L. , H4. As a result, the front end portion of the large-diameter hole Ha is closed by the upper plate portion 8a of the first lid body 8. When the rotating arm 7 is located at the open position, the upper plate portion 8a stands substantially vertically with the rear end portion located on the upper side. The position of the first lid 8 at this time is the folding position.

補強部８ｂは、上板部８ａを補強することにより、第１蓋体８が展開位置に位置したときに上板部８ａの中央部が下方に撓むのを防止するためのものである。補強部８ｂの前後方向及び左右方向の長さは、上板部８ａの同方向の各長さよりそれぞれ短く設定されており、補強部８ｂは、その中央が上板部８ａの中央とほぼ一致するように配置されている。したがって、上板部８ａの外周部が補強部８ｂから前後左右の全方向に向かって突出している。しかも、補強部８は、第１蓋体８が展開位置に位置したとき、補強部８ｂの前側及び左右の各側面とハッチＨの第１、第３、第４の各辺Ｈ１、Ｈ３、Ｈ４との各間に所定の大きさの隙間がそれぞれ形成されるように、その外形寸法が定められている。 The reinforcing portion 8b is for reinforcing the upper plate portion 8a to prevent the central portion of the upper plate portion 8a from being bent downward when the first lid body 8 is located at the deployed position. The lengths of the reinforcing portion 8b in the front-rear direction and the left-right direction are set to be shorter than the lengths of the upper plate portion 8a in the same direction, and the center of the reinforcing portion 8b substantially coincides with the center of the upper plate portion 8a. Are arranged as follows. Therefore, the outer peripheral portion of the upper plate portion 8a protrudes from the reinforcing portion 8b in all directions of front, rear, left and right. In addition, when the first lid 8 is positioned at the unfolded position, the reinforcing portion 8 has the front, left and right side surfaces of the reinforcing portion 8b and the first, third, and fourth sides H1, H3, and H4 of the hatch H. The outer dimensions are determined so that gaps of a predetermined size are formed between the two.

図１、図３及び図５に示すように、第２蓋体９は、第１蓋体８と同様に、上板部９ａと、その下面に設けられた補強部９ｂとを有している。上板部９ａは、平面視長方形の平板によって構成されている。上板部９ａの厚さ及び左右方向の長さは、第１蓋体８の上板部８ａの厚さ及び左右方向の長さと同一に設定されている。しかも、上板部９ａは、上板部８ａに対し左右方向において同一位置に配置されている。上板部９ａの前後方向の長さは、展開位置に位置しているときの上板部８ａの後端面と第２の辺Ｈ２との間の距離より短く設定されている。 As shown in FIGS. 1, 3, and 5, the second lid body 9 has an upper plate portion 9 a and a reinforcing portion 9 b provided on the lower surface thereof, like the first lid body 8. . The upper plate portion 9a is constituted by a flat plate having a rectangular shape in plan view. The thickness of the upper plate portion 9a and the length in the left-right direction are set to be the same as the thickness of the upper plate portion 8a of the first lid 8 and the length in the left-right direction. Moreover, the upper plate portion 9a is disposed at the same position in the left-right direction with respect to the upper plate portion 8a. The length of the upper plate portion 9a in the front-rear direction is set to be shorter than the distance between the rear end surface of the upper plate portion 8a and the second side H2 when the upper plate portion 9a is located at the unfolded position.

後述するように、第１蓋体８が展開位置に位置すると、第２蓋体９も展開位置に位置する。第２蓋体９が展開位置に位置すると、上板部９ａが水平になり、その左右の両側部がライナーＬを介して床面Ｓａ上に載置される。第２蓋体９の上板部９ａの厚さが第１蓋体８の上板部８ａの厚さと同一であるから、第１、第２蓋体８，９が展開位置に位置すると、両者の上面（上板部８ａ，９ａの上面）が同一水平面上に位置する。また、第２蓋体９が展開位置に位置すると、上板部９ａの前端面が上板部８ａの後端面にほぼ接触する。ここで、上板部９ａの前後方向の長さが展開位置に位置しているときの上板部８ａの後端面と第２の辺Ｈ２との間の距離より短く設定されているので、第２蓋体９が展開位置に位置すると、上板部９ａの後端面と第２の辺Ｈ２との間に隙間が形成される。上板部９ａは、その隙間の分を除いて大径孔部Ｈａの後端部を閉じる。 As will be described later, when the first lid 8 is located at the deployed position, the second lid 9 is also located at the deployed position. When the second lid body 9 is located at the unfolded position, the upper plate portion 9a becomes horizontal, and both left and right side portions thereof are placed on the floor surface Sa via the liner L. Since the thickness of the upper plate portion 9a of the second lid 9 is the same as the thickness of the upper plate portion 8a of the first lid 8, when the first and second lids 8 and 9 are located at the unfolded position, The upper surfaces (the upper surfaces of the upper plate portions 8a and 9a) are located on the same horizontal plane. Further, when the second lid body 9 is located at the unfolded position, the front end surface of the upper plate portion 9a substantially contacts the rear end surface of the upper plate portion 8a. Here, the length in the front-rear direction of the upper plate portion 9a is set to be shorter than the distance between the rear end surface of the upper plate portion 8a and the second side H2 when the upper plate portion 9a is located at the unfolded position. When the two lids 9 are located at the unfolded position, a gap is formed between the rear end surface of the upper plate portion 9a and the second side H2. The upper plate portion 9a closes the rear end portion of the large-diameter hole Ha except for the gap.

補強部９ｂは、第１蓋体８の補強部８ｂと同様に、上板部９ａを補強することにより、第２蓋体８が展開位置に位置したときに上板部９ａの中央部が下方に撓むのを防止するためのものである。補強部９ｂの左右方向の長さは、補強部８ｂの左右の長さと同一に設定されており、補強部９ｂは左右方向において補強部８ｂと同一位置に配置されている。したがって、第２蓋体９が展開位置に位置したときには、補強部９ｂの左右の両側面と第３、第４の辺Ｈ３，Ｈ４との間には、補強部８ｂの左右の両側面と第３、第４の辺Ｈ３，Ｈ４との間に形成される隙間と同一の大きさの隙間が形成される。補強部９ｂの前後方向の長さは、上板部９ａの前後方向の長さより長くなっており、その差の分だけ補強部９ｂの前端部が上板部９ａの前端部から前方に突出している。この突出量は、第１蓋体８の上板部８ａの後端部が補強部８ｂの後端部から後方へ突出する突出量と同一に設定されている。したがって、第１、第２蓋体８，９が展開位置に位置すると、上板部８ａの補強部８ｂから後方へ突出した後端部が補強部９ｂの前端部上面に載置される。補強部９ｂの後端面は、上板部９ａの後端面と同一平面上に位置させられている。 The reinforcing portion 9b reinforces the upper plate portion 9a in the same manner as the reinforcing portion 8b of the first lid body 8, so that the central portion of the upper plate portion 9a is downward when the second lid body 8 is located at the unfolded position. This is to prevent bending. The length in the left-right direction of the reinforcing portion 9b is set to be the same as the left and right length of the reinforcing portion 8b, and the reinforcing portion 9b is disposed at the same position as the reinforcing portion 8b in the left-right direction. Therefore, when the second lid body 9 is located at the unfolded position, the left and right side surfaces of the reinforcing portion 8b and the left and right side surfaces of the reinforcing portion 9b are located between the left and right side surfaces of the reinforcing portion 9b and the third and fourth sides H3 and H4. 3. A gap having the same size as the gap formed between the fourth side H3 and the fourth side H4 is formed. The length in the front-rear direction of the reinforcing portion 9b is longer than the length in the front-rear direction of the upper plate portion 9a, and the front end portion of the reinforcing portion 9b protrudes forward from the front end portion of the upper plate portion 9a by the difference. Yes. This protrusion amount is set to be the same as the protrusion amount at which the rear end portion of the upper plate portion 8a of the first lid 8 protrudes rearward from the rear end portion of the reinforcing portion 8b. Therefore, when the first and second lids 8 and 9 are located at the unfolded position, the rear end portion protruding rearward from the reinforcing portion 8b of the upper plate portion 8a is placed on the upper surface of the front end portion of the reinforcing portion 9b. The rear end surface of the reinforcing portion 9b is positioned on the same plane as the rear end surface of the upper plate portion 9a.

補強部９ｂの後端面には、断面Ｌ字状の型鋼からなる補助部材９ｃが固定されている。補助部材９ｃは、補強部９ｂの後端面の左右方向における一端から他端まで延びている。補助部材９ｃの上面には、耐摩耗性に冨み、かつ摩擦抵抗が小さい樹脂、例えばアクリル樹脂からなる受け板９ｄが固定されている。この受け板９ｄは、平面視における形状及び寸法が補助部材９ｃの上面の形状及び寸法と同一に設定されている。受け板９ｄの上面は、補強部９ｂの上面と同一平面上に位置させられている。したがって、補強部９ｂの後端面と第２の辺Ｈ２との間に形成される隙間は、受け板９ｄの前後方向における幅の分だけ狭くなっており、第２蓋体９は、実際には、受け板９ｄの後端面第２のと第２の辺Ｈ２との間に形成される隙間を除いて大径孔部Ｈａの後端部を閉じている。 An auxiliary member 9c made of steel having an L-shaped cross section is fixed to the rear end surface of the reinforcing portion 9b. The auxiliary member 9c extends from one end to the other end in the left-right direction of the rear end surface of the reinforcing portion 9b. On the upper surface of the auxiliary member 9c, a receiving plate 9d made of a resin, such as an acrylic resin, which has high wear resistance and low frictional resistance is fixed. The receiving plate 9d is set to have the same shape and size in plan view as the shape and size of the upper surface of the auxiliary member 9c. The upper surface of the receiving plate 9d is positioned on the same plane as the upper surface of the reinforcing portion 9b. Therefore, the gap formed between the rear end surface of the reinforcing portion 9b and the second side H2 is narrowed by the width in the front-rear direction of the receiving plate 9d, and the second lid body 9 is actually The rear end portion of the large-diameter hole Ha is closed except for a gap formed between the rear end surface second and the second side H2 of the receiving plate 9d.

第２蓋体９は、第１蓋体８の展開位置と折畳位置との間の回動変位に伴って展開位置と折畳位置との間を変位するようになっている。そのために、次の構成が採用されている。すなわち、補強部９ｂの前端下部は、補強部８ｂの後端下部にヒンジ１０を介して回動可能に連結されている。ヒンジ１０の回動軸線（図示せず）は、回動アーム７ｂの回動軸線たる第１回動軸線Ｌ１と平行になっており、ヒンジ１０の回動軸線が第２回動軸線になっている。図３及び図９〜図１３に示すように、補強部９ｂの左右の両側面の後端部には、車輪１１が第１回動軸線Ｌ１と平行な軸線を中心としてそれぞれ回動可能に設けられている。補強部９ｂの左右両側面と大径孔部Ｈａの第３及び第４の辺Ｈ３，Ｈ４と各間には、ガイドレール（ガイド部）１２がそれぞれ設けられている。各ガイドレール１２，１２は、その後端面から前方へ向かって水平に延びる水平部１２ａと、この水平部１２ａの前端部に連設され、前方へ向かうにしたがって上方へ向かうように傾斜する傾斜部１２ａとから構成されている。ガイドレール１２は、支持面Ｈｂに調節ねじ１３を介して支持されており、調節ねじ１３を正逆方向へ適宜に回動させることによって上下方向へ位置調節可能になっている。ガイドレール１２の上下方向の位置は、第２蓋体９が展開位置に位置したときに、車輪１１がガイドレール１２の上面にほぼ接するように調節されている。 The second lid 9 is displaced between the deployed position and the folded position in accordance with the rotational displacement between the deployed position and the folded position of the first lid 8. Therefore, the following configuration is adopted. That is, the lower part of the front end of the reinforcing part 9b is rotatably connected to the lower part of the rear end of the reinforcing part 8b via the hinge 10. The pivot axis (not shown) of the hinge 10 is parallel to the first pivot axis L1 that is the pivot axis of the pivot arm 7b, and the pivot axis of the hinge 10 is the second pivot axis. Yes. As shown in FIGS. 3 and 9 to 13, the wheels 11 are provided at the rear ends of the left and right side surfaces of the reinforcing portion 9 b so as to be rotatable about an axis parallel to the first rotation axis L <b> 1. It has been. Guide rails (guide portions) 12 are respectively provided between the left and right side surfaces of the reinforcing portion 9b and the third and fourth sides H3 and H4 of the large-diameter hole portion Ha. Each of the guide rails 12 and 12 is provided with a horizontal portion 12a that extends horizontally from the rear end surface to the front, and an inclined portion 12a that is connected to the front end portion of the horizontal portion 12a and inclines upward toward the front. It consists of and. The guide rail 12 is supported on the support surface Hb via an adjustment screw 13 and can be adjusted in the vertical direction by appropriately rotating the adjustment screw 13 in the forward and reverse directions. The vertical position of the guide rail 12 is adjusted such that the wheel 11 is substantially in contact with the upper surface of the guide rail 12 when the second lid 9 is located at the deployed position.

上記構成において、いま図６に示すように、回動アーム７が閉位置に位置し、第１、第２蓋体８，９が展開位置に位置しているものとする。回動アーム７を閉位置から開位置側へ向かって回動させると、第１蓋体８が回動変位しつつライナーＬから上方へ離間する。第１蓋体８は、その後端部が前端部より上方に位置するように回動変位する。すると、図７に示すように、第１蓋体８の後端部にヒンジ１０を介して回動可能に連結された第２蓋体９の前端部が、第１蓋体８の回動変位に伴って上方及び前方へ向かって移動する。第２蓋体９の前端部の前方への移動に追随して第２蓋体９の後端部が前方へ移動する。このとき、車輪１１，１１がガイドレール１２，１２の水平部１２ａ，１２ａ上をその後端部から前端部側へ向かって転動する。したがって、第２蓋体９は、円滑に変位することができる。回動アーム７が開位置に向かって所定の角度だけ回動するまでは、車輪１１がガイドレール１２の水平部１２ａ上を転動する。回動アーム７の回動角度を越えて回動すると、車輪１１がガイドレール１２の傾斜部１２ｂ上を転動するようになる。回動アーム７がさらに回動すると、車輪１１が傾斜部１２ａか上方へ離れ、第２蓋体９の前端部が第１蓋体８の後端部によりヒンジ１０を介して吊り下げられた状態になる。図８に示すように、回動アーム７が開位置に達すると、第１、第２蓋体８，９が折畳位置に位置する。第１蓋体８は、その後端部が前端部より上側に位置した状態でほぼ鉛直に起立し、第２蓋体９は、その前端部が後端部より上側に位置した状態で鉛直に起立する。 In the above configuration, as shown in FIG. 6, it is assumed that the rotating arm 7 is located at the closed position and the first and second lid bodies 8 and 9 are located at the deployed position. When the rotating arm 7 is rotated from the closed position toward the open position, the first lid body 8 is separated upward from the liner L while being rotationally displaced. The first lid 8 is rotationally displaced so that the rear end portion thereof is located above the front end portion. Then, as shown in FIG. 7, the front end portion of the second lid body 9 that is pivotably connected to the rear end portion of the first lid body 8 via the hinge 10 is rotated and displaced by the first lid body 8. Accordingly, it moves upward and forward. Following the movement of the front end of the second lid 9 forward, the rear end of the second lid 9 moves forward. At this time, the wheels 11 and 11 roll on the horizontal portions 12a and 12a of the guide rails 12 and 12 from the rear end portion toward the front end portion side. Therefore, the second lid body 9 can be displaced smoothly. The wheels 11 roll on the horizontal portion 12a of the guide rail 12 until the rotating arm 7 rotates by a predetermined angle toward the open position. When the rotation arm 7 is rotated beyond the rotation angle, the wheel 11 rolls on the inclined portion 12 b of the guide rail 12. When the rotating arm 7 further rotates, the wheel 11 is separated from the inclined portion 12a upward, and the front end portion of the second lid body 9 is suspended by the rear end portion of the first lid body 8 via the hinge 10. become. As shown in FIG. 8, when the rotating arm 7 reaches the open position, the first and second lid bodies 8 and 9 are positioned at the folding position. The first lid 8 stands substantially vertically with its rear end positioned above the front end, and the second lid 9 stands vertically with its front end positioned above the rear end. To do.

回動アーム７を開位置から閉位置側へ回動させる場合において、回動アーム７を開位置から所定の角度だけ閉位置側へ回動させると、車輪１１がガイドレール１２の傾斜部１２上に接触する。このとき、第２蓋体９は、鉛直状態になっているが、車輪１１が傾斜部１２に接触しているので、その状態から回動アーム７をさらに閉位置側へ回動させたとき、第２蓋体９の後端部は前方へ移動することなく、確実に後方へ移動する。したがって、第２蓋体９を折畳位置から展開位置側へ確実に変位させることができる。回動アーム７が閉位置まで回動すると、第１、第２蓋体８，９が展開位置に位置してハッチＨの上端開口部（大径孔部Ｈａ）を、その後端側の一部を除いて閉じる。後述するように、ハッチＨの後端側の一部、つまり第２蓋体９の後端部とハッチＨの第２の辺Ｈ２との間に形成される隙間は、防塵カバー１４によって閉じられる。 When the rotating arm 7 is rotated from the open position to the closed position side, when the rotating arm 7 is rotated from the open position to the closed position side by a predetermined angle, the wheel 11 moves on the inclined portion 12 of the guide rail 12. To touch. At this time, the second lid 9 is in a vertical state, but since the wheel 11 is in contact with the inclined portion 12, when the rotating arm 7 is further rotated from the state to the closed position side, The rear end portion of the second lid body 9 moves reliably without moving forward. Therefore, the second lid body 9 can be reliably displaced from the folding position to the deployed position side. When the rotating arm 7 is rotated to the closed position, the first and second lid bodies 8 and 9 are positioned at the unfolded position so that the upper end opening (large-diameter hole portion Ha) of the hatch H is part of the rear end side. Close except. As will be described later, a part of the rear end side of the hatch H, that is, a gap formed between the rear end portion of the second lid 9 and the second side H2 of the hatch H is closed by the dust cover 14. .

ここで、仮に上板部９ａの左右両側部の後端面が補強部９ｂの後端面と同一平面上に位置しているものとすると、第２蓋体９が図７に示す鉛直状態又は図３、図１１及び図１２に示す傾斜した状態で車輪１１がガイドレール１２の上面に接触するときに、上板部９ａの左右両側部の後端部が大径孔部Ｈａ内に入り込もうとする。ところが、上板部９ａの左右の長さが大径孔部Ｈａの左右方向の長さより長いので、上板部９ａの左右両側部は、大径部Ｈａ内に入り込むことができず、ライナーＬを介して床面Ｓａに突き当たってしまう。この結果、第２蓋体９が展開位置と折畳位置との間を変位するときには、車輪１１がガイドレール１２上を転動することができず、上板部９ａの後端部の両側部が第３、第４の辺Ｈ３，Ｈ４に沿うライナーＬ上を摺動する。このため、ライナーＬが上板部９ａによって傷付けられたり、上板部９ａの後端両側部に過大な荷重が作用して変形するおそれがある。 Here, assuming that the rear end surfaces of the left and right side portions of the upper plate portion 9a are located on the same plane as the rear end surface of the reinforcing portion 9b, the second lid 9 is in the vertical state shown in FIG. When the wheel 11 contacts the upper surface of the guide rail 12 in the inclined state shown in FIGS. 11 and 12, the rear end portions of the left and right sides of the upper plate portion 9a try to enter the large-diameter hole Ha. However, since the left and right lengths of the upper plate portion 9a are longer than the left and right lengths of the large-diameter hole portion Ha, the left and right side portions of the upper plate portion 9a cannot enter the large-diameter portion Ha, and the liner L Will hit the floor surface Sa. As a result, when the second lid body 9 is displaced between the unfolded position and the folded position, the wheel 11 cannot roll on the guide rail 12, and both side portions of the rear end portion of the upper plate portion 9a. Slides on the liner L along the third and fourth sides H3 and H4. For this reason, there exists a possibility that the liner L may be damaged by the upper board part 9a, or an excessive load may act on both the rear-end both sides of the upper board part 9a, and may deform | transform.

このような問題を回避するために、この開閉装置１においては、上板部９ａの左右両側部の後端部に後端面から前方へ向かう所定長の範囲にわたって延びる切欠き部９ｅが形成されている。つまり、第２蓋体９が展開位置と折畳位置との間を変位するのに伴って車輪１１がガイドレール１２上を転動する際に、上板部９ａの後端部の左右両側部がライナーＬに接触するであろう範囲が切り欠かれているのである。この切欠き部９ｅが形成されることにより、上板部９ａの後端部の幅が狭められている。上板部９ａの後端部の幅は、大径孔部Ｈａの左右方向の幅より狭くすればよいが、この実施の形態では、さらに狭くされ、補強部９ｂの左右方向の幅と同一にされている。換言すれば、切欠き部９ｅの左右方向の幅が、上板部９ａが補強部９ｂから左右方向に突出する突出量と同一に設定されているのである。 In order to avoid such a problem, in the opening / closing device 1, a notch 9e extending over a predetermined length from the rear end surface to the front is formed at the rear end of the left and right sides of the upper plate portion 9a. Yes. That is, when the wheel 11 rolls on the guide rail 12 as the second lid 9 is displaced between the deployed position and the folded position, the left and right side portions of the rear end portion of the upper plate portion 9a. The area that would contact the liner L is cut away. By forming this notch portion 9e, the width of the rear end portion of the upper plate portion 9a is narrowed. The width of the rear end portion of the upper plate portion 9a may be made narrower than the width in the left-right direction of the large-diameter hole Ha, but in this embodiment, it is further narrowed to be the same as the width in the left-right direction of the reinforcing portion 9b. Has been. In other words, the width in the left-right direction of the notch portion 9e is set to be the same as the protrusion amount of the upper plate portion 9a protruding in the left-right direction from the reinforcing portion 9b.

また、上記のように、第２蓋体９の受け板９ｄとハッチＨの第２の辺Ｈ２との間に隙間が形成されている。しかも、切欠き部９ｅが形成されることにより、第２蓋体９の左右両側部の後端部と第３、第４辺Ｈ３，Ｈ４との各間にも隙間が形成されている。この結果、第２蓋体９とハッチＨとの後端部間には、左右に長い扁平な「凹」字状をなす隙間が形成されており、ハッチＨの後端部が上方に向かって「凹」字状に開放されている。この開放部を閉じるために、防塵カバー（第１カバー）１４が用いられている。 Further, as described above, a gap is formed between the receiving plate 9d of the second lid 9 and the second side H2 of the hatch H. In addition, by forming the notch portion 9e, a gap is also formed between the rear end portions of the left and right side portions of the second lid body 9 and the third and fourth sides H3 and H4. As a result, a gap that forms a flat “concave” shape that is long on the left and right is formed between the rear end portions of the second lid 9 and the hatch H, and the rear end portion of the hatch H faces upward. It is open in a “concave” shape. A dustproof cover (first cover) 14 is used to close the opening.

図１及び図３に示すように、防塵カバー１４は、左右方向に延びる主部１４ａと、この主部１４ａの左右の両端部から前方へ突出する突出部１４ｂとを有している。主部１４ａは、ハッチＨの第２の辺Ｈ２に沿って配置されており、その後端部がヒンジ１５を介してライナーＬに回動可能に連結されている。ヒンジ１５の回動軸線（図示せず）は、回動アーム７の回動軸線たる第１回動軸線Ｌ１と平行に配置されており、第３回動軸線になっている。したがって、防塵カバー１４は、その前端部が後端部を中心として上下方向に回動可能になっている。主部１４ａの左右方向の長さは、大径孔部Ｈａの左右方向の長さより長くなっており、防塵カバー１４がほぼ水平な状態に回動すると、主部１４ａの左右の両側部がライナーＬの第３及び第４の辺Ｈ３，Ｈ４に沿う部分に載置される。このときの防塵カバー１４の回動位置がカバー位置である。防塵カバー１４がカバー位置に位置したときには、主部１４ａの前端面が展開位置に位置している第２蓋体９の上板部９ａの後端面にほぼ接触するとともに、主部１４ａの前端部が受け板９ｄの上面に載置される。この結果、第２蓋体９の後端部（受け板９ｄの後端部）とハッチＨの第２の辺Ｈ２との間に形成される隙間が、防塵カバー１４によって遮蔽される。しかも、防塵カバー１４の厚さが第２蓋体９の上板部９ａの厚さと同一に設定されているので、防塵カバー１４がカバー位置に位置したときには、防塵カバー１４の上面が第２蓋体９の上面、つまり上板部９ａの上面と同一平面上に位置する。 As shown in FIGS. 1 and 3, the dust cover 14 has a main portion 14a extending in the left-right direction, and protruding portions 14b protruding forward from both left and right end portions of the main portion 14a. The main portion 14 a is disposed along the second side H <b> 2 of the hatch H, and a rear end portion thereof is rotatably connected to the liner L via the hinge 15. A rotation axis (not shown) of the hinge 15 is arranged in parallel with the first rotation axis L1 which is the rotation axis of the rotation arm 7, and is a third rotation axis. Therefore, the dust-proof cover 14 has a front end portion that is rotatable in the vertical direction around the rear end portion. The length in the left-right direction of the main portion 14a is longer than the length in the left-right direction of the large-diameter hole Ha, and when the dust cover 14 rotates in a substantially horizontal state, the left and right side portions of the main portion 14a are liners. It is mounted on a portion along the third and fourth sides H3 and H4 of L. The rotation position of the dustproof cover 14 at this time is the cover position. When the dust cover 14 is positioned at the cover position, the front end surface of the main portion 14a substantially contacts the rear end surface of the upper plate portion 9a of the second lid 9 positioned at the unfolded position, and the front end portion of the main portion 14a. Is placed on the upper surface of the receiving plate 9d. As a result, a gap formed between the rear end portion of the second lid body 9 (the rear end portion of the receiving plate 9d) and the second side H2 of the hatch H is shielded by the dustproof cover 14. Moreover, since the thickness of the dustproof cover 14 is set to be the same as the thickness of the upper plate portion 9a of the second lid 9, when the dustproof cover 14 is located at the cover position, the upper surface of the dustproof cover 14 is the second lid. It is located on the same plane as the upper surface of the body 9, that is, the upper surface of the upper plate portion 9a.

突出部１４ｂは、第２蓋体９が展開位置に位置したときに切欠き部９ｅによって形成される隙間を遮蔽するためのものであり、防塵カバー１４がカバー位置に位置したときには、左側の突出部１４ｂの左側部が第３の辺Ｈ３に沿うライナーＬ上に載置され、右側の突出部１４ｂの右側部が第４の辺Ｈ４に沿うライナーＬ上に載置される。しかも、左側の突出部１４ｂの右側面及び右側の突出部１４ｂの左側面が、上板部９ａの切欠き部９ｅに臨む左右の両側面にそれぞれほぼ接している。ただし、図１０に示すように、突出部１４ｂの先端面１４ｃは、第２蓋体９が展開位置に位置しているときにおける上板部９ａの切欠き部９ｅに臨む後端面９ｆより若干後方に位置している。したがって、防塵カバー１４がカバー位置に位置したとき、突出部１４ｂは切欠き部９ｅの大部分を遮蔽するが、突出部１４ｂの先端面１４ｃと上板部９ａの後端面９ｆとの間には、隙間Ｓｐが形成される。 The protrusion 14b is for shielding the gap formed by the notch 9e when the second lid 9 is located at the unfolded position. When the dust cover 14 is located at the cover position, the protrusion 14b protrudes on the left side. The left side portion of the portion 14b is placed on the liner L along the third side H3, and the right side portion of the right protrusion 14b is placed on the liner L along the fourth side H4. In addition, the right side surface of the left protruding portion 14b and the left side surface of the right protruding portion 14b are substantially in contact with the left and right side surfaces facing the notch portion 9e of the upper plate portion 9a. However, as shown in FIG. 10, the front end surface 14c of the projecting portion 14b is slightly behind the rear end surface 9f facing the notch portion 9e of the upper plate portion 9a when the second lid body 9 is located at the unfolded position. Is located. Accordingly, when the dust cover 14 is positioned at the cover position, the protrusion 14b shields most of the notch 9e, but between the front end surface 14c of the protrusion 14b and the rear end surface 9f of the upper plate portion 9a. A gap Sp is formed.

突出部１４ｂの先端面１４ｃを、第２蓋体９が展開位置に位置しているときにおける上板部９ａの切欠き部９ｅに臨む後端面９ｆより若干後方に位置させたのは、次の理由による。すなわち、図３及び図６に示すように、第１回動軸線Ｌ１が、第２回動軸線たるヒンジ１０の回動軸線より上方に配置されている。このため、回動アーム７が開位置側から閉位置側へ向かって回動する場合において、回動アーム７が閉位置に対して所定の大きさの第１角度だけ手前の位置に達すると、第２蓋体９の後端部が展開位置に位置しているときの第２蓋体９の後端部と同一位置に達する。その後、回動アーム７が閉位置に対して所定の大きさの第２角度（第２角度＜第１角度）だけ手前の位置まで回動する間は、回動アーム７の閉位置側への回動に伴って第２蓋体９の後端部が展開位置を越えて後方へ移動する。その後、回動アーム７が第２角度を越えて閉位置まで回動する間は、第２蓋体９の後端部が前方へ移動する。そして、回動アーム７が閉位置に達すると、第２蓋体９が展開位置に達する。 The front end surface 14c of the projecting portion 14b is positioned slightly behind the rear end surface 9f facing the notch portion 9e of the upper plate portion 9a when the second lid body 9 is positioned at the unfolded position. Depending on the reason. That is, as shown in FIGS. 3 and 6, the first rotation axis L1 is disposed above the rotation axis of the hinge 10 as the second rotation axis. For this reason, when the pivot arm 7 pivots from the open position side toward the close position side, when the pivot arm 7 reaches a position in front of the closed position by a first angle of a predetermined size, The rear end portion of the second lid body 9 reaches the same position as the rear end portion of the second lid body 9 when it is located at the unfolded position. After that, while the pivot arm 7 is pivoted to the near position by a predetermined second angle (second angle <first angle) with respect to the closed position, the pivot arm 7 moves toward the closed position. With the rotation, the rear end portion of the second lid body 9 moves backward beyond the deployed position. Thereafter, while the pivot arm 7 pivots beyond the second angle to the closed position, the rear end portion of the second lid body 9 moves forward. When the rotating arm 7 reaches the closed position, the second lid body 9 reaches the deployed position.

このように、回動アーム７が閉位置近傍に位置しているときに、第２蓋体９の後端部が展開位置を越えて後方へ移動するため、仮に第２蓋体９が展開位置に位置しているときに突出部１４ｂの先端面１４ｃと上板部９ａの後端面９ｆを接触させるようにすると、回動アーム７が閉位置側から開位置側へ向かって第１角度を越えて回動しようとするときに、先端面１４ｃが後端面９ｆに突き当たる。その結果、第２蓋体９がそれ以上後方へ移動することができなくなってしまう。そこで、図１１〜図１３に示すように、補強部９ａの両側面の後端部における上部には、前後方向に延びるガイド部材（ガイド部）１６が設けられ、突出部１４ｂの先端部下面には、耐摩耗性に富み、かつ摩擦抵抗の少ない材質、例えばアクリル樹脂からなるスライド部材１７が設けられている。 Thus, when the rotating arm 7 is positioned in the vicinity of the closed position, the rear end portion of the second lid 9 moves rearward beyond the deployed position, so that the second lid 9 is temporarily deployed. When the tip end surface 14c of the projecting portion 14b and the rear end surface 9f of the upper plate portion 9a are brought into contact with each other, the rotating arm 7 exceeds the first angle from the closed position side toward the open position side. When trying to rotate, the front end surface 14c comes into contact with the rear end surface 9f. As a result, the second lid 9 can no longer move rearward. Therefore, as shown in FIGS. 11 to 13, a guide member (guide portion) 16 extending in the front-rear direction is provided at the upper portion of the rear end portion of both side surfaces of the reinforcing portion 9 a, and is provided on the lower surface of the distal end portion of the protruding portion 14 b. Is provided with a slide member 17 made of a material having high wear resistance and low frictional resistance, such as acrylic resin.

ガイド部材１６及びスライド部材１７は、図１１に示すように、回動アーム７が閉位置に対し第１角度より大きい所定の角度だけ手前の位置まで回動したときに、スライド部材１７がガイド部材１６の上面に接触するように配置されている。スライド部材１７がガイド部材１６に接触した状態において、回動アーム７が閉位置側へ回動し、それに伴って第２蓋体９が後方へ移動すると、スライド部材１７がガイド部材１６によって上方へ移動させられ、それによって防塵カバー１４がカバー位置から上方へ回動させられる。防塵カバー１４が上方へ最も回動したときの位置が逃げ位置である。ガイド部材１６の先端面は、上板部９ａの後端面９ｆにほとんど段差なく滑らかに連なっており、第２蓋体９が展開位置から最も後方へ移動したときには、図１２に示すように、スライド部材１７の一部又は全部がガイド部材１６の後端部を乗り越えて上板部９ａ上に乗り上がる。これから明かなように、この実施の形態の開閉装置１においては、ガイド部材１６、スライド部材１７及び上板部９ａの一部により、防塵カバー１４を開閉回動させる第１回動手段１８が構成されている。その後、回動アーム７が閉位置に対して第２角度だけ手前の位置に達すると、それ以降は回動アーム７の閉位置側への回動に伴って第２蓋体９が前方へ移動する。すると、スライド部材１７が上板部９ａから後方へ移動し、ガイド部材１６上に乗る。そして、回動アーム７が閉位置に達し、第２蓋体９が展開位置に達すると、図１３に示すように、スライド部材１７がガイド部材１６の先端部に形成された凹部１６ａ内に入り込む。すると、防塵カバー１４がカバー位置に位置することができるようになり、防塵カバー１４の両側部がライナーＬに載置されるとともに、前端部が受け板９ｄの上面に載置される。 As shown in FIG. 11, the guide member 16 and the slide member 17 are configured such that when the rotary arm 7 is rotated to a position closer to the front by a predetermined angle than the first angle with respect to the closed position, It arrange | positions so that the upper surface of 16 may be contacted. In a state where the slide member 17 is in contact with the guide member 16, when the rotary arm 7 is rotated to the closed position side and the second lid body 9 is moved rearward accordingly, the slide member 17 is moved upward by the guide member 16. As a result, the dust cover 14 is rotated upward from the cover position. The position when the dust cover 14 is most rotated upward is the escape position. The front end surface of the guide member 16 is smoothly connected to the rear end surface 9f of the upper plate portion 9a with almost no step, and when the second lid body 9 moves most rearward from the deployed position, as shown in FIG. Part or all of the member 17 rides over the rear end portion of the guide member 16 and rides on the upper plate portion 9a. As is apparent from the above, in the opening / closing device 1 of this embodiment, the first rotation means 18 for opening / closing and rotating the dust-proof cover 14 is constituted by a part of the guide member 16, the slide member 17 and the upper plate portion 9a. Has been. Thereafter, when the rotating arm 7 reaches a position that is a second angle relative to the closed position, the second lid body 9 moves forward along with the rotation of the rotating arm 7 toward the closed position. To do. Then, the slide member 17 moves rearward from the upper plate portion 9 a and gets on the guide member 16. When the rotating arm 7 reaches the closed position and the second lid body 9 reaches the deployed position, the slide member 17 enters the recess 16a formed at the distal end portion of the guide member 16, as shown in FIG. . Then, the dust cover 14 can be positioned at the cover position, and both side portions of the dust cover 14 are placed on the liner L, and the front end portion is placed on the upper surface of the receiving plate 9d.

ここで、ガイド部材１６の先端部が第２蓋体９の上板部９ａの後端面９ｆに連なっているので、凹部１６ａは、ガイド部材１６の先端面より後方に位置している。しかも、スライド部材１７の先端が防塵カバー１４の突出部１４ｂの先端面１４ｃと前後方向において同一平面上に位置している。したがって、スライド部材１７が凹部１６ａに入むまで第２蓋体９が前方へ移動すると、凹部１６ａがガイド部材１６の先端から後方へ離れている分だけ第２蓋体９の後端面９ｆと防塵カバー１４の突出部１４ｂの先端面１４ｃとのが前後方向に離間し、後端面９ｆと先端面１４ｃとの間に隙間Ｓｐが形成される。 Here, since the front end portion of the guide member 16 is continuous with the rear end surface 9 f of the upper plate portion 9 a of the second lid body 9, the concave portion 16 a is located behind the front end surface of the guide member 16. Moreover, the tip of the slide member 17 is located on the same plane in the front-rear direction as the tip surface 14 c of the protrusion 14 b of the dust cover 14. Therefore, when the second lid body 9 moves forward until the slide member 17 enters the recess 16a, the rear end surface 9f of the second lid 9 and the dust-proofing are as much as the recess 16a is rearward from the tip of the guide member 16. The protrusion 14b of the cover 14 is separated from the front end surface 14c in the front-rear direction, and a gap Sp is formed between the rear end surface 9f and the front end surface 14c.

後端面９ｆと先端面１４ｃとの間の隙間Ｓｐをそのまま放置すると、そこから各種の部材等がハッチＨ内に入り込み、ハッチＨを通って階下に落下する危険性がある。そこで、この開閉装置１では、図９及び図１３に示すように、後端面９ｆと先端面１４ｃとの間の隙間Ｓｐを隙間カバー（第２カバー）１９によって遮蔽するようになっている。隙間カバー１９は、突出部１４ｂとほぼ同一の左右方向の幅を有しており、左右方向において突出部１４ｂと同一位置に配置されている。隙間カバー１９の前端部は、ヒンジ２０を介して第２蓋体９の上板部９ａの上面に回動可能に取り付けられている。ヒンジ２０の回動軸線（図示せず）は、回動アーム７の回動軸線たる第１回動軸線Ｌ１と平行に配置されており、ヒンジ２０の回動軸線が第３回動軸線になっている。隙間カバー１９の後端部は、後端面９ｆと先端面１４ｃとの間の隙間Ｓｐを越えて突出部１４ｂまで延びており、第２蓋体９が展開位置に位置しているときには、防塵カバー１４の突出部１４ｂの先端部上面に載置されている。このときの隙間カバー１９の回動位置が遮蔽位置である。したがって、隙間カバー１９は、遮蔽位置に位置すると隙間Ｓｐを遮蔽する。 If the gap Sp between the rear end surface 9f and the front end surface 14c is left as it is, there is a risk that various members and the like enter the hatch H from there and fall down the floor through the hatch H. Therefore, in the opening / closing device 1, as shown in FIGS. 9 and 13, the gap Sp between the rear end face 9f and the front end face 14c is shielded by the gap cover (second cover) 19. The gap cover 19 has substantially the same width in the left-right direction as the protrusion 14b, and is disposed at the same position as the protrusion 14b in the left-right direction. The front end portion of the gap cover 19 is rotatably attached to the upper surface of the upper plate portion 9a of the second lid body 9 via a hinge 20. A rotation axis (not shown) of the hinge 20 is arranged in parallel with the first rotation axis L1 that is the rotation axis of the rotation arm 7, and the rotation axis of the hinge 20 becomes the third rotation axis. ing. The rear end portion of the gap cover 19 extends beyond the gap Sp between the rear end surface 9f and the front end surface 14c to the protruding portion 14b, and when the second lid 9 is located at the unfolded position, the dustproof cover 14 is mounted on the upper surface of the tip of the protruding portion 14b. The rotation position of the gap cover 19 at this time is the shielding position. Therefore, when the gap cover 19 is located at the shielding position, the gap Sp is shielded.

上記のように、第２蓋体９が展開位置近傍に位置しているときには、防塵カバー１４がカバー位置から上方へ回動しているから、少なくとも第２蓋体９が展開位置近傍に位置しているときには、防塵カバー１４が隙間カバー１９に突き当たらないようにするために、隙間カバー１９を上方へ回動させておく必要がある。そこで、隙間カバー１９近傍に位置する補強部９ｂの側面には、第２回動手段２１が設けられている。 As described above, when the second lid 9 is located in the vicinity of the deployed position, the dust cover 14 is rotated upward from the cover position, so that at least the second lid 9 is located in the vicinity of the deployed position. In order to prevent the dust cover 14 from coming into contact with the gap cover 19, the gap cover 19 needs to be rotated upward. Therefore, the second rotating means 21 is provided on the side surface of the reinforcing portion 9b located in the vicinity of the gap cover 19.

第２回動手段２１は、図１１〜図１３に示すように、レバー２２を有している。このレバー２２は、隙間カバー１９近傍に位置する補強部９ｂの側面に沿って配置されており、その中央部が第１回動軸線Ｌ１と平行な軸２３を介して補強部９ｂの側面に回動可能に支持されている。したがって、レバー２３は上下方向へ回動可能である。レバー２２の後端部には、当接部材２４が設けられている。この当接部材２４と対向する上板部９ａには、貫通孔９ｇ（図１０参照）が形成されている。したがって、当接部材２４は、貫通孔９ｇを通って隙間カバー１９に突き当たることが可能になっている。レバー２３の前端部には、当接板２５が固定されている。補強部９ｂの側面には、ストッパ２６が上下方向へ位置調節可能に設けられている。このストッパ２６に当接板２５が突き当たることにより、レバー２３の後端部の上方（レバー２３の反時計方向）への回動限界位置が規制されている。レバー２３の回動限界位置は、ストッパ２６の上下方向の位置を調節することによって適宜変更可能である。 The 2nd rotation means 21 has the lever 22, as shown in FIGS. The lever 22 is disposed along the side surface of the reinforcing portion 9b located in the vicinity of the gap cover 19, and the center portion rotates around the side surface of the reinforcing portion 9b via the shaft 23 parallel to the first rotation axis L1. It is supported movably. Therefore, the lever 23 can be rotated in the vertical direction. A contact member 24 is provided at the rear end of the lever 22. A through hole 9g (see FIG. 10) is formed in the upper plate portion 9a facing the contact member 24. Therefore, the contact member 24 can abut against the gap cover 19 through the through hole 9g. A contact plate 25 is fixed to the front end of the lever 23. A stopper 26 is provided on the side surface of the reinforcing portion 9b so that the position can be adjusted in the vertical direction. When the abutting plate 25 abuts against the stopper 26, the upper limit position of rotation of the rear end portion of the lever 23 (counterclockwise of the lever 23) is restricted. The rotation limit position of the lever 23 can be changed as appropriate by adjusting the vertical position of the stopper 26.

レバー２２の軸２３と当接板２５との間に位置する部位には、下方へ向かって延びる脚部２７が固定されている。この脚部２６は、引っ張りばね２８によって後方へ付勢されている。これにより、レバー２２の後端部が上方へ回動するようにレバー２２が回動付勢されており、当接板２５がストッパ２６に突き当たっている。この状態においては、当接部材２４の上端部が貫通孔９ｇを貫通して上方へ突出し、隙間カバー１９を上方へ回動させている。このときの隙間カバー１９の回動位置が待機位置である。したがって、隙間カバー１０の待機位置は、ストッパ２６を上下方向へ適宜移動させてレバー２３の回動限界位置を調節することによって調節可能である。 A leg portion 27 extending downward is fixed to a portion located between the shaft 23 of the lever 22 and the contact plate 25. The leg portion 26 is urged rearward by a tension spring 28. Accordingly, the lever 22 is urged to rotate so that the rear end portion of the lever 22 is rotated upward, and the contact plate 25 abuts against the stopper 26. In this state, the upper end portion of the contact member 24 protrudes upward through the through hole 9g, and the gap cover 19 is rotated upward. The rotation position of the gap cover 19 at this time is the standby position. Therefore, the standby position of the gap cover 10 can be adjusted by adjusting the rotation limit position of the lever 23 by appropriately moving the stopper 26 in the vertical direction.

脚部２６の下端部には、車輪２９が回転自在に設けられている。この車輪２９は、図１２に示すように、展開位置近傍に位置している第２蓋体９が折畳位置側から展開位置側へ変位する場合において、防塵カバー１４が逃げ位置からカバー位置側へ回動し始めると、ガイドレール１２の水平部１２ａの上面に接するようになっている。車輪２９が水平部１２ａに接すると、図１２と図１３との比較から明かなように、第２蓋体９が展開位置側へ変位するのに伴ってレバー２２が引っ張りばね２８の付勢力に抗して時計方向へ回動させられる。その結果、隙間カバー１９が自重によって待機位置側から遮蔽位置側へ回動する。そして、第２蓋体９が展開位置に達すると隙間カバー１９が遮蔽位置に達し、隙間Ｓｐを遮蔽する。逆に、第２蓋体９が展開位置から折畳位置側へ変位する場合には、第２蓋体９が折畳位置側へ変位し始めると同時に、隙間カバー１９が第２回動手段２１によって遮蔽位置から待機位置側へ回動させられるとともに、防塵カバー１４が第１回動手段１８によってカバー位置から逃げ位置側へ回動させられるが、隙間カバー１９は防塵カバー１４より大きく回動させられる。したがって、隙間カバー１９及び防塵カバー１４は、互いに干渉することなく円滑に回動することができる。 A wheel 29 is rotatably provided at the lower end portion of the leg portion 26. As shown in FIG. 12, when the second lid 9 located in the vicinity of the unfolded position is displaced from the folding position side to the unfolded position side, the wheel 29 is moved from the escape position to the cover position side. When it starts to rotate, it comes into contact with the upper surface of the horizontal portion 12 a of the guide rail 12. When the wheel 29 comes into contact with the horizontal portion 12a, as is clear from the comparison between FIG. 12 and FIG. 13, the lever 22 is subjected to the urging force of the tension spring 28 as the second lid body 9 is displaced toward the deployment position. It is counterclockwise rotated. As a result, the gap cover 19 is rotated from the standby position side to the shielding position side by its own weight. When the second lid 9 reaches the unfolded position, the gap cover 19 reaches the shielding position and shields the gap Sp. Conversely, when the second lid body 9 is displaced from the unfolded position to the folding position side, the gap cover 19 is moved to the second rotating means 21 at the same time as the second lid body 9 starts to be displaced to the folding position side. The dust cover 14 is rotated from the cover position to the standby position and the dust cover 14 is rotated from the cover position to the escape position side by the first rotation means 18, but the gap cover 19 is rotated more than the dust cover 14. It is done. Therefore, the gap cover 19 and the dust cover 14 can smoothly rotate without interfering with each other.

上記構成のハッチの開閉装置１によれば、第１、第２の二つの蓋体８，９によってハッチＨを開閉するようになっており、二つの蓋体８，９は、展開位置に位置しているときには一つの蓋体と同様、同一平面上に位置してハッチＨを閉じる。その一方、ハッチＨを開くときには、二つの蓋体８，９が一直線上に並んだ状態で回動することなく、互いに折り畳まれるように変位する。したがって、ハッチＨを開閉する際に第１、第２蓋体８，９が必要とする空間を狭くすることができる。 According to the hatch opening and closing device 1 configured as described above, the hatch H is opened and closed by the first and second lid bodies 8 and 9, and the two lid bodies 8 and 9 are located at the unfolded position. In the same manner as in the case of one lid, the hatch H is closed on the same plane. On the other hand, when the hatch H is opened, the two lid bodies 8 and 9 are displaced so as to be folded together without rotating in a state where they are aligned. Therefore, the space required by the first and second lid bodies 8 and 9 when opening and closing the hatch H can be reduced.

なお、この発明は、上記の実施の形態に限定されるものでなく、その要旨を逸脱しない範囲において適宜変更可能である。
例えば、上記の実施の形態においては、ハッチＨを閉じるために、第１、第２蓋体８，９の上板部８ａ，９ａを床面ＳａにライナーＬを介して載置しているが、展開位置に位置したときにおける上板部８ａ，８ｂの両者を合わせた大きさをハッチＨの上端開口部（大径孔部Ｈａ）の大きさと同一にすることにより、上板部８ａ，８ｂを展開位置において大径孔部Ｈａに嵌合させるようにしてもよい。その場合には、第１、第２蓋体８，９が展開位置近傍において前後方向へほとんど移動しないようにする必要がある。そのために、回動アーム７の回動軸線たる第１回動軸線Ｌ１を、第１、第２蓋体８，９を回動可能に連結するヒンジ１０の回動軸線（第２回動軸線）とほぼ同一の高さにする必要がある。 In addition, this invention is not limited to said embodiment, In the range which does not deviate from the summary, it can change suitably.
For example, in the above embodiment, the upper plate portions 8a and 9a of the first and second lids 8 and 9 are placed on the floor surface Sa via the liner L in order to close the hatch H. By making the size of the upper plate portions 8a and 8b combined at the unfolded position the same as the size of the upper end opening (large diameter hole portion Ha) of the hatch H, the upper plate portions 8a and 8b May be fitted to the large-diameter hole Ha at the unfolded position. In that case, it is necessary that the first and second lids 8 and 9 hardly move in the front-rear direction in the vicinity of the deployed position. For this purpose, the first rotation axis L1 that is the rotation axis of the rotation arm 7 is connected to the rotation axis (second rotation axis) of the hinge 10 that rotatably connects the first and second lid bodies 8 and 9. It should be almost the same height.

この発明の一実施の形態を示す平面図である。It is a top view which shows one embodiment of this invention. 図１のＸ−Ｘ線に沿う断面図である。It is sectional drawing which follows the XX line of FIG. 図１のＹ―Ｙ線に沿う拡大断面図である。It is an expanded sectional view which follows the YY line of FIG. 同実施の形態において用いられている第１蓋体を示す図であって、図４（Ａ）はその平面図、図４（Ｂ）、（Ｃ）はそれぞれ図４（Ａ）のＢ−Ｂ線、Ｃ−Ｃ線に沿う断面図である。It is a figure which shows the 1st cover body used in the embodiment, Comprising: FIG. 4 (A) is the top view, FIG. 4 (B) and (C) are each BB of FIG. 4 (A). It is sectional drawing which follows a line and CC line. 同実施の形態において用いられている第２蓋体を示す図であって、図５（Ａ）はその平面図、図５（Ｂ）、（Ｃ）はそれぞれ図５（Ａ）のＢ−Ｂ線、Ｃ−Ｃ線に沿う断面図である。It is a figure which shows the 2nd cover body used in the embodiment, Comprising: FIG. 5 (A) is the top view, FIG.5 (B) and (C) are each BB of FIG.5 (A). It is sectional drawing which follows a line and CC line. 回動アームが閉位置に位置したときにおける図１のＺ−Ｚ線に沿う断面図である。It is sectional drawing which follows the ZZ line | wire of FIG. 1 when a rotation arm is located in a closed position. 回動アームが開位置の手前に位置したときにおける図１のＺ−Ｚ線に沿う断面図である。It is sectional drawing which follows the ZZ line | wire of FIG. 1 when a rotation arm is located in front of an open position. 回動アームが開位置に位置したときにおける図１のＺ−Ｚ線に沿う断面図である。It is sectional drawing which follows the ZZ line | wire of FIG. 1 when a rotation arm is located in an open position. 図１のＡ円部の拡大図である。It is an enlarged view of the A circle part of FIG. 隙間カバーを省略した状態で示す図９と同様の図である。FIG. 10 is a view similar to FIG. 9 shown with a gap cover omitted. 第２蓋体が折畳位置側から展開位置側へ変位する場合においてスライド部材がガイド部材に接触し始めたときの状態を示す図９のＸ−Ｘ線に沿う拡大断面図である。FIG. 10 is an enlarged cross-sectional view taken along line XX of FIG. 9 showing a state when the slide member starts to contact the guide member when the second lid body is displaced from the folding position side to the deployed position side. 第２蓋体が最も後方へ移動したときの状態を示す図１１と同様の断面図である。It is sectional drawing similar to FIG. 11 which shows a state when a 2nd cover body moves most back. 第２蓋体が展開位置に位置したときの状態を示す図１１と同様の断面図である。It is sectional drawing similar to FIG. 11 which shows a state when a 2nd cover body is located in an expansion | deployment position.

Explanation of symbols

Ｈハッチ
Ｈ１第１の辺
Ｈ２第２の辺
Ｈ３第３の辺
Ｈ４第４の辺
Ｌ１第１回動軸線
Ｓａ床面
Ｓｐ隙間
１ハッチの開閉装置
７回動アーム
８第１蓋体
９第２蓋体
９ｆ切欠き部
１２ガイドレール（ガイド部）
１４防塵カバー（第１カバー）
１４ｂ突出部
１８第１回動手段
２１第２回動手段 H hatch H1 first side H2 second side H3 third side H4 fourth side L1 first rotation axis Sa floor surface Sp gap 1 hatch opening / closing device 7 rotary arm 8 first lid 9 second Lid 9f Notch 12 Guide rail (guide part)
14 Dust-proof cover (first cover)
14b Projecting portion 18 First rotating means 21 Second rotating means

Claims

In a hatch opening and closing device for opening and closing a hatch having a rectangular shape in plan view that opens on the floor of the housing,
A base end portion is provided at a position along the first side of the hatch of the housing so as to be pivotable in a vertical direction around a horizontal first rotation axis parallel to the first side, and a distal end portion is provided. A pivot arm that pivots and displaces between a closed position and an open position located above the closed position; one end portion of the hatch opening located on the first side; and the first Opening and closing the other end located on the second side parallel to the side, respectively, and connecting one end adjacent to each other so as to be rotatable about a second rotation axis parallel to the first rotation axis A first lid and a second lid,
The tip of the pivot arm is fixed to the first lid,
The first lid and the second lid are displaced between a deployed position and a folded position in accordance with a rotation between the closed position and the open position of the rotation arm,
When the first and second lids are located at the unfolded position, the first and second lids are both substantially horizontal and close one end and the other end of the hatch, and are located at the folded position. both open-out, respectively one end and the other end of the hatch and spaced from the hatch while standing substantially vertically upwards when you are,
When the first rotation axis is located above the second rotation axis and the second lid is located in a predetermined range near the unfolded position, the other end of the second lid When the second lid is located at the deployed position, the other end of the second lid is located closer to the second side than the same end when the portion is located at the deployed position. A gap is formed between the portion and the second side,
At a portion along the second side of the hatch of the housing, the base end portion of the first cover has a cover position and a relief position centered on a third rotation axis parallel to the first and second rotation axes. The second cover is provided between the second cover and the first cover so that at least the other end of the second cover is on the second side from the tip of the first cover. A first rotating means for rotating the first cover from the cover position to the escape position when being located at a position;
When the first cover is located at the cover position, both side portions in the direction along the second side are adjacent to the third and fourth sides orthogonal to the first and second sides. It is placed on the floor surface of the casing, and the tip is placed on the upper surface of the second lid to shield the gap formed between the second side and the second lid. The hatch opening and closing device is characterized in that the tip end portion of the first cover is spaced upward from the second lid when the escape position is located .

Further comprising a guide portion provided respectively along the interior of the upper Symbol third and fourth sides of the said third and fourth sides of the hatch, this deployment the second lid and the deployed position When it is located between a position away from the position toward the folding position by a predetermined distance, both side portions in the direction along the second side of the other end portion of the second lid body are the guides. The hatch opening and closing device according to claim 1, wherein the hatch opening and closing device is supported by a portion so as to be movable in a direction along each of the third and fourth sides.

Protruding portions that extend toward the second lid side are provided on both side portions in the direction along the second side of the tip portion of the first cover, and the second lid body that faces each of the projecting portions. A notch portion into which the protruding portion is fitted when the first cover is located at the cover position is provided on both side portions of the first lid, and the second lid body faces the front end surface of the protruding portion and the notched portion. A gap is formed between the other end surface of
The base end portion of the second cover is shielded around the fourth rotation axis parallel to the first to third rotation axes on both sides of the other end of the second lid that faces each protrusion. The second lid body is provided so as to be rotatable between a position and a standby position, and at least the second cover is attached to the second lid body in accordance with the displacement of the second lid body from the folding position to the deployment position side. The tip of the first cover moves from the first side of the first cover to the second side of the first cover from the first side by a predetermined distance. Second rotating means for positioning the second cover at the standby position in a predetermined range until the state is provided,
When the second cover is positioned at the shielding position, a tip end portion is placed on the upper surface of the projecting portion of the first cover to shield the gap between the second lid and the projecting portion. When the second cover is moved from the folding position side to the unfolded position side, the front end of the first cover is located below the front end portion of the second cover. The hatch opening and closing device according to claim 1 , wherein the hatch opening and closing device is rotated upward so that the portion enters .