JP3581962B2

JP3581962B2 - Workbench

Info

Publication number: JP3581962B2
Application number: JP2001248726A
Authority: JP
Inventors: 直樹垰
Original assignee: 長谷川工業株式会社
Priority date: 2000-10-10
Filing date: 2001-08-20
Publication date: 2004-10-27
Anticipated expiration: 2021-08-20
Also published as: JP2002188285A

Description

【０００１】
【発明の属する技術分野】
この発明は、折り畳み可能な作業台に関する。
【０００２】
【従来の技術】
折り畳み可能な作業用の台としては、脚立が一般的である。
【０００３】
【発明が解決しようとする課題】
従来の脚立は、折畳みが容易であるという利便性は有しているものの、作業スペースが少ないおよび天板上での作業が禁止されているなどの問題があり、その改良が要望されている。
【０００４】
この発明の目的は、折畳みが容易でしかも作業性および安全性にも優れている作業台を提供することにある。
【０００５】
【課題を解決するための手段および発明の効果】
この発明による作業台は、左右支柱およびこれらの間に渡し止められた少なくとも１つの踏桟よりなり下広がり状態で対向する前後一対の脚と、前後脚の上端部間に渡されて前後端部が前後脚の上端部に回動可能に支持された逆Ｖ字状に二つ折り可能な天板と、各脚の上端部に設けられて天板の前後端部を受ける前後天板受け桟と、左右支柱の上端部と天板の前後端部とを互いに回動自在に連結する連結金具と、前後脚間にＸ字状に渡されて、作業台使用時における前後脚の開き止めを行うとともに、天板を逆Ｖ字状に二つ折りにした際に前後脚同士を互いに近づけるように動く一対の斜め部材とを備えており、各斜め部材は、Ｖ字状に二つ折り可能に連結された長尺部および短尺部よりなり、その上下端部が対応する前後脚にそれぞれ回動可能に支持されるとともに、各斜め部材の長尺部同士が互いに回動可能に連結されており、斜め部材の上端部と天板受け桟との連結中心をＡおよびＣ、斜め部材の下端部と踏桟との連結中心をＢおよびＤ、斜め部材の長尺部と短尺部との連結中心をＥおよびＦとして、折り畳み初期において、斜め部材の長尺部同士の連結中心を基準として、ＡおよびＣは、互いに近づきかつ上方に移動し、ＢおよびＤは、互いに離れかつ上方に移動し、ＥおよびＦは、互いに近づきかつ下方に移動するようになされているものである。
【０００６】
この発明の作業台によると、天板上に広い作業場所が確保されるとともに、前後脚連結手段によって前後脚に対する天板の回動が阻止される。そして、作業終了後に天板を逆Ｖ字状に二つ折りにすることにより、各斜め部材が前後脚同士を互いに近づけるように動き、作業台全体がコンパクトに折り畳まれる。
【０００７】
各斜め部材の上端部回動中心から連結部中心までの距離と下端部回動中心から連結部中心までの距離との差は、一方の斜め部材の上端部回動中心から他方の斜め部材の下端部回動中心までの距離に実質的に等しくなされる。このようにすると、作業終了後に天板を二つ折りにすると、これに伴って、各斜め部材の下端部が前後脚の踏桟に対し、同上端部が天板受け桟に対しそれぞれ回動するとともに、各斜め部材の短尺部が長尺部に対して回動し、作業台全体がコンパクトに折り畳まれる。
【０００８】
ここで、「各斜め部材の上端部回動中心から連結部中心までの距離と下端部回動中心から連結部中心までの距離との差が、一方の斜め部材の上端部回動中心から他方の斜め部材の下端部回動中心までの距離に等しい。」とは、図２において、ＡＢ＝ＣＥ−ＢＥおよびＣＤ＝ＡＦ−ＤＦが成り立つことを意味する。そして、「実質的に」とは、図３において、折畳み時中心面からの点Ａ，Ｂ，Ｃ，Ｄ，Ｅ，Ｆの距離が同じでないことを考慮して、各線分の折畳み時中心面に沿った距離が等しくなるように、それぞれの線分の長さが微調整されることを意味している。
【０００９】
なお、この明細書において、「＝」は、「実質的に等しい」場合についても使用するものとする。
【００１０】
また、この明細書において、「Ｖ字状に二つ折り可能」は、中間部分でＶ字状に二つに折れることが可能でかつ逆Ｖ字状には二つに折ることができないことを意味し、「逆Ｖ字状に二つ折り可能」は、中間部分で逆Ｖ字状に二つに折れることが可能でかつＶ字状には二つに折ることができないことを意味する。これらの語は、水平な部材に対してだけでなく、斜め部材に対しても使用され、二つに折れる部分が上方（真上または斜め上）に移動する場合に、「逆Ｖ字状に二つ折り」といい、下方（真下または斜め下）に移動する場合に、「Ｖ字状に二つ折り」という。Ｖ字状に二つ折り可能な部材は、例えば、２つの部材を突き合わせてこれらを突き合わせ部の上縁において互いに回動可能なように連結することにより得ることができ、逆Ｖ字状に二つ折り可能な部材は、例えば、２つの部材を突き合わせてこれらを突き合わせ部の下縁において互いに回動可能なように連結することにより得ることができる。
【００１１】
この発明の作業台において、天板の前後端部の輪郭形状が左右方向から見て凸円弧形とされるとともに、天板受け桟の上面が左右方向から見て凹円弧状に形成されており、折畳み時に天板の前後端部が天板受け桟に案内されるようになされていることがある。このようにすると、天板にかかる荷重が天板受け桟によって支持されるとともに、折畳みがスムーズに行え、しかも、作業台開閉時の手ばさみが防止される。
【００１２】
また、連結金具は、支柱の上端部に固定された支柱への取付部と、支柱への取付部に連なり支柱の上端面を覆うカバー部と、カバー部に連なり天板の左右側部に回動可能に取り付けられている天板への取付部とよりなることがある。このようにすると、連結金具によって、支柱の上端面がカバーされ、支柱上端部を覆うカバーが不要となり、部品数を減少することができる。
【００１３】
さらにまた、天板受け桟および所定の踏桟に、折畳み終了時に前後に対応するもの同士が係合する収納金具がそれぞれ設けられていることがある。収納金具は、種々の構成が可能であるが、例えば、開口を前後方向外向きに向けた略コ字状でかつその底壁の上縁および下縁に水平突出状の係合爪が設けられており、作業台を折り畳んだ状態で係合爪同士が摺り合わせ状に交差するものとされる。これにより、折畳み状態で各脚同士が左右方向に動いてがたつくこと（横ずれ現象）が防止され、運搬・保管を容易に行うことができる。また、収納金具は、折畳み時に支柱同士がちょうど平行になるように形成され、これにより、多数の作業台を横にして重ねても崩れることがない。
【００１４】
【発明の実施の形態】
この発明の実施の形態を、以下図面を参照して説明する。
【００１５】
この明細書において、前後については、図２の右を前、左を後というものとし、左右は、後方に向かっていうものとする。
【００１６】
図１から図１２までは、この発明の第１実施形態を示している。
【００１７】
この発明による作業台は、左右支柱(3)および支柱(3)間に渡し止められた４段の踏桟(4)よりなる前後一対の脚(1)(2)と、逆Ｖ字状に二つ折り可能な天板(5)と、各脚(1)(2)の上端部に設けられて天板(5)の前後端部を受ける前後天板受け桟(6)と、左右支柱(3)の上端部と天板(5)の前後端部とを互いに回動可能に連結する連結金具(7)と、前脚(1)の踏桟(4)と後天板受け桟(6)との間および後脚(2)の踏桟(4)と前天板受け桟(6)との間にそれぞれ斜めに渡された斜め部材(8)と、天板受け桟(6)および所定の（この例では最下段の）踏桟(4)にそれぞれ設けられた収納金具(9)とを備えており、図２に示す使用状態から図３に示す収納状態に折り畳むことができるようになされている。
【００１８】
各支柱(3)および踏桟(4)は、いずれもアルミニウム押出型材製である。各支柱(3)は、横断面コ字形に形成されて、開口を内に向けられている。各踏桟(4)は、横断面略台形に形成されており、その上壁（大きい図だけで説明）が、内方に張り出されている。前後脚(1)(2)は、それぞれ若干下広がりとされており、各支柱(3)と地面とのなす角は、８３°程度とされている。
【００１９】
天板(5)は、図４から図７までに詳しく示すように、前後一対の足場板(11)(12)と、前足場板(11)の連結側端部（後端部）および後足場板(12)の連結側端部（前端部）にそれぞれ固定された固定金具(13)(14)と、固定金具(13)(14)同士を相対的に回動可能に連結する可動金具(15)と、前足場板(11)の前端部および後足場板(12)の後端部に固定された前後のカバー部(16)と、可動金具(15)の左右端部を覆うようにタッピンねじ(18)によって固定金具(13)(14)に取り付けられた左右のカバー部(17)とよりなる。
【００２０】
前後足場板(11)(12)は、押出方向が前後方向のアルミニウム押出型材とされており、固定金具(13)(14)、可動金具(15)および前後カバー部(16)は、押出方向が左右方向のアルミニウム押出型材とされている。
【００２１】
前後足場板(11)(12)は、踏面部となる上壁、内方突出縁付きの左右壁および中間補強壁よりなる。
【００２２】
各固定金具(13)(14)は、横断面略コ字状に形成されており、前後足場板(11)(12)の連結端部側の開口を塞ぐとともに、可動金具(15)と組み合わされて天板(5)を二つ折りするためのヒンジ手段を構成する機能を併せ持っている。
【００２３】
図４および図５に詳しく示すように、前足場板(11)に固定された固定金具(13)の下壁部には、後方に開口した凹溝(32)を有する前足場板側ヒンジ構成部(31)が、後足場板(12)に固定された固定金具(14)の下壁部には、前方に開口した凹溝(34)を有する後足場板側ヒンジ構成部(33)がそれぞれ設けられている。可動金具(15)は、前足場板側ヒンジ構成部(31)の凹溝(32)内に回動可能に嵌め入れられている前側ヒンジ構成部(35)と、後足場板側ヒンジ構成部(33)の凹溝(34)内に回動可能嵌め入れられている後側ヒンジ構成部(36)とを有している。
【００２４】
前足場板側ヒンジ構成部(31)の凹溝(32)の下壁部は、平坦であり、その後縁部には、上方にのびる係合部(37)が設けられている。同様に、後足場板側ヒンジ構成部(33)の凹溝(34)の下壁部は、平坦であり、その前縁部には、上方にのびる係合部(38)が設けられている。前足場板側ヒンジ構成部(31)の凹溝(32)内には、その上壁部の中程から下壁部の前縁に至る４分の１円の大きさの横断面円弧状案内面が設けられ、後足場板側ヒンジ構成部(33)の凹溝(34)内には、その上壁部の中程から下壁部の後縁に至る４分の１円の大きさの横断面円弧状案内面が設けられている。可動金具(15)の前側ヒンジ構成部(35)は、対応する凹溝(32)の円弧状案内面に沿う外周面を有する横断面略円弧状の屈曲部(39)と、これの下縁部に連なる後向き折返し状係合部(40)とよりなり、可動金具(15)の後側ヒンジ構成部(36)は、対応する凹溝(34)の円弧状案内面に沿う外周面を有する横断面略円弧状の屈曲部(41)と、これの下縁部に連なる前向き折返し状係合部(42)とよりなる。各折返し状係合部(40)(42)の先端部は、２分の１円の大きさの横断面円弧状とされており、この先端部が当接している凹溝の係合部(37)(38)の基部には、横断面円弧状の案内面が設けられている。
【００２５】
なお、各固定金具(13)(14)には、可動金具(15)の左右方向への抜けを防止している左右カバー部(17)をタッピンねじ(18)で取り付けるための横断面Ｃ字状のタッピンねじ挿通部(43)(44)が形成されている。
【００２６】
天板受け桟(6)は、アルミニウム押出型材製で、横断面略方形状とされている。天板受け桟(6)は、踏桟(4)と同様に左右支柱(3)間に渡し止められているが、その断面形状は踏桟(4)とは異なっている。すなわち、天板受け桟(6)の上壁は、図６に示すように、横断面凹の円弧状上面(6a)を有するように形成されている。この形状は、折畳み時に天板(5)の前後端部を案内するためのものであり、これに対応して、天板(5)の前後端部すなわち天板(5)の前後カバー部(16)が次のように形成されている。
【００２７】
天板(5)のカバー部(16)は、前後で同一の形状であるので、前カバー部(16)について、図６および図７を参照して説明する。
【００２８】
天板(5)の前カバー部(16)は、前足場板(11)の上壁の端部から同下壁の端部近くに至る横断面半円形に形成された摺動壁(51)と、摺動壁(51)の上端に連なりかつ前足場板(11)の上壁に沿ってのびる上リベット止め壁(52)と、摺動壁(51)の下端に連なりかつ前足場板(11)の下壁に沿ってのびる下リベット止め壁(53)と、摺動壁(51)の上端に連なって下方にのび前足場板(11)の端部開口を塞いでいる閉鎖壁(54)と、閉鎖壁(54)の下端から前足場板(11)の下壁に沿ってのびる位置決め壁(55)とよりなる。
【００２９】
左右支柱(3)と天板(5)とを連結している連結金具(7)は、支柱(3)の外側壁の上端部にリベットで固定された支柱への取付部(61)と、支柱への取付部(61)に連なり支柱(3)の上端面を覆うカバー部(62)と、カバー部(62)に連なり天板(5)の側部に段付ボルト(64)およびナット(65)により回動可能に取り付けられている天板への取付部(63)とよりなる。図８に示すように、連結金具(7)の天板への取付部(63)および天板(5)の前足場板(11)にあけられたボルト軸部挿通孔に左右方向の軸を有する段付ボルト(64)の段付軸部(64a)がゆるく挿通されている。
【００３０】
図７に示すように、天板受け桟(6)の凹円弧状上面(6a)は、半径が前カバー部(16)の摺動壁(51)の半径にほぼ等しくかつ略１／４円の円弧を有しており、作業台使用状態では、前カバー部(16)の摺動壁(51)の下面部分が天板受け桟(6)に置かれている。したがって、天板(5)の前足場板(11)は、段付ボルト(64)の軸を中心として図６の時計方向に回動することができ、支柱(3)に対する天板(5)の回動が可能とされている。
【００３１】
各斜め部材(8)は、Ｖ字状に二つ折り可能に連結された長尺部(21)および短尺部(22)よりなる。両斜め部材(8)の長尺部(21)の中間部同士がＸ字状にかつ互いに回動可能に連結ピン(23)により連結されている。
【００３２】
下から３段目の踏桟のほぼ中央には、各斜め部材(8)の短尺部(22)の下端部を回動可能に支持する下支持金具(19)が取り付けられ、天板受け桟(6)の対応する位置には、各斜め部材(8)の長尺部(21)の上端部を回動可能に支持する上支持金具(20)が取り付けられている。
【００３３】
各斜め部材(8)の長尺部(21)は、長尺の角パイプ(24)と、角パイプ(24)の上端部に嵌め合わせられた端部連結金具(25)と、角パイプ(24)の下端部に嵌め合わせられた突き合わせ部連結金具(26)とよりなり、同様に、短尺部(22)は、短尺の角パイプ(27)と、角パイプ(27)の上端部に嵌め合わせられかつ長尺部(21)の突き合わせ部連結金具(26)と連結ピン(30)により回動可能に連結された突き合わせ部連結金具(28)と、角パイプ(27)の下端部に嵌め合わせられた端部連結金具(29)とよりなる。
【００３４】
長尺部(21)の突き合わせ部連結金具(26)および短尺部(22)の突き合わせ部連結金具(28)は、いずれも角筒状本体部分を有し、その本体部分同士が互いに突き合わされかつ逆Ｖ字状となる方向にのみ二つ折り可能なように連結されている。すなわち、長尺部(21)の突き合わせ部連結金具(26)に、本体部分の内側壁から上方にのびる耳部(26a)が設けられ、短尺部(22)の突き合わせ部連結金具(28)に、本体部分の外側壁から上方にのびる耳部(28a)が対向状に設けられ、これらの耳部(26a)(28a)同士が突き合わせ面の上縁に軸線があるピン(30)で互いに回動可能に連結されている。
【００３５】
長尺部(21)および短尺部(22)の端部金具(25)(29)は、左右方向にのびる押出型材製であり、その端部に円筒部(25a)(29a)が形成されている。
【００３６】
天板受け桟(6)に設けられている上支持金具(20)は、天板受け桟(6)に下から嵌め合わされているコ字状の取付部(71)と、取付部(71)の内側壁に内方突出状に設けられた左右の対向壁よりなる支持部(72)とよりなる。取付部(71)は、取付部(71)および天板受け桟(6)を貫通するボルト(73)にナットが締め付けられることによって、天板受け桟(6)に固定されている。そして、各斜め部材(8)の長尺部(21)の端部金具(25)の円筒部(25a)に、上支持金具(20)の支持部(72)の対向壁を貫通するボルト(74)がゆるく挿通されることにより、斜め部材(8)の上端部が天板受け桟(6)に対して回動可能とされている。
【００３７】
また、踏桟(4)に設けられている下支持金具(19)は、踏桟(4)に下から嵌め合わされているコ字状の取付部(75)と、取付部(75)の下壁に下方突出状に設けられた左右の対向壁よりなる支持部(76)とよりなる。取付部(75)は、取付部(75)および踏桟(4)を貫通するボルト(77)にナットが締め付けられることによって、踏桟(4)に固定されている。そして、各斜め部材(8)の短尺部(22)の端部金具(29)の円筒部(29a)に、下支持金具(19)の支持部(76)の対向壁を貫通するボルト(78)がゆるく挿通されることにより、斜め部材(8)の下端部が踏桟(4)に対して回動可能とされている。
【００３８】
収納金具(9)は、図１０および図１１に示すように、開口を前後方向外向きに向けた略コ字状の金具で、その底壁の上縁および下縁に水平突出状の係合爪(9a)(9b)が設けられている。収納金具(9)は、すべて同じ形状のものが使用されており、係合爪(9a)(9b)は、図１０に示すように、前脚(1)の踏桟(4)に固定されているものでは、その底壁の上縁右半部および下縁左半部に位置し、後脚(2)の踏桟(4)に固定されているものでは、その底壁の上縁左半部および下縁右半部に位置している。したがって、作業台を折り畳んだ状態では、図１１に示すように、上側の係合爪(9a)同士および下側の係合爪(9b)同士がそれぞれ摺り合わせ状に交差し、これにより、前後脚(1)(2)同士が左右にずれることが防止される。また、この折畳み状態において、収納金具(9)同士の突き合わせ面は、支柱(3)の長さ方向と平行になされている。したがって、図３に示す折畳み状態において、支柱(3)同士の間に斜め部材(8)が収まるための間隔が保持されるとともに、運搬・保管時の横ずれが防止される。
【００３９】
上記の作業台は、使用状態では、天板(5)の前足場板(11)と後足場板(12)とが突き合わされ、斜め部材(8)の長尺部(21)と短尺部(22)とが突き合わされている。そして、天板(5)は、図５に示すように、前足場板(11)と後足場板(12)との突き合わ面の下縁部分を回動中心として逆Ｖ字状に折畳みは可能であるが、Ｖ字状への折畳みは不可能とされており、天板(5)にかかる荷重が天板(5)、前後脚(1)(2)および斜め部材(8)によってしっかりと受け止められる。前後脚(1)(2)同士が広がろうとする力は、斜め部材(8)を逆Ｖ字状に折り畳もうとする方向に働くことから、斜め部材(8)は、前後脚(1)(2)が互いに開こうとするのを阻止する開き止め機能を果たしている。
【００４０】
この作業台は、次のようにして折り畳まれる。以下の説明において、ＡおよびＣは、斜め部材(8)の上端部と天板受け桟(6)との連結中心（ボルト(74)の軸線）を、ＢおよびＤは、斜め部材(8)の下端部と踏桟(4)との連結中心（ボルト(78)の軸線）を、ＥおよびＦは、斜め部材の長尺部(21)と短尺部(22)との連結中心（ピン(30)の軸線）をそれぞれ示している。
【００４１】
天板(5)は上述のように逆Ｖ字状に二つ折り可能であるから、まず、図１２に実線で示すように、天板(5)を逆Ｖ字状に折り畳む。各斜め部材(8)は、長尺部(21)と短尺部(22)との突き合わせ面の上縁部分を回動中心としてＶ字状に二つ折り可能とされているので（図９参照）、Ｖ字状に折り畳まれていく。このときの前後の脚(1)(2)は、まず、図１２の鎖線から実線（互いに広がる方向）に移動する。すなわち、斜め部材(8)の長尺部(21)同士の連結中心（連結ピン(23)の軸線）を基準として、ＡおよびＣは、互いに近づきかつ上方に移動し、ＢおよびＤは、互いに離れかつ上方に移動し、ＥおよびＦは、互いに近づきかつ下方に移動する。図１２の状態よりさらに天板(5)を折り畳んでいくと、前後の脚(1)(2)同士は互いに近づき、最終的には、図３に示すように、短尺部(22)は長尺部(21)に対して１８０°回動し、短尺部(22)は、下から３段目の踏桟の下方で支柱(3)と平行な位置に収められ、長尺部(21)は、その下端部が短尺部(22)に重なるとともに、両斜め部材(8)の長尺部(21)同士が左右に重ね合わせられて前後脚(1)(2)の間に収められる。なお、踏桟(4)の斜め部材(8)と干渉する部分には、切欠き(4a)が設けられている（図１および図９参照）。
【００４２】
上記において、図３に示すようにコンパクトに折り畳まれる条件として、各斜め部材(8)の上端部回動中心ＡおよびＣから連結部中心ＦおよびＥまでの距離（線分ＡＦおよび線分ＡＥの長さであり、長尺部(21)の長さに相当している）と各斜め部材(8)の下端部回動中心ＤおよびＢから連結部中心ＦおよびＥまでの距離（線分ＤＦおよび線分ＢＥの長さであり、短尺部(22)の長さに相当している）との差が、一方の斜め部材(8)の上端部回動中心ＡおよびＣから他方の斜め部材(8)の下端部回動中心ＢおよびＤまでの距離（線分ＡＢおよび線分ＣＤの長さであり、斜め部材(8)全体の支柱(3)に沿った長さに相当している）とが実質的に等しくなされている。すなわち、線分ＡＢ＝線分ＣＤ≒線分ＣＥ−線分ＢＥ＝線分ＡＦ−線分ＤＦとなされている。ここで、点Ａおよび点Ｂは、折畳み状態の対称中心面近くに位置させられ、点Ｅおよび点Ｆは、これより若干外側の前支柱の後面および後支柱の前面にそれぞれ位置させられ、また、点Ｂおよび点Ｅは、これよりさらに外側の支柱に重なるところに位置させられている。上記の「実質的に等しい」は、図３において、点Ａ，Ｂ，Ｃ，Ｄ，Ｅ，Ｆの折畳み時中心面からの距離が同じでないことを考慮して、前後の脚(1)(2)の間に斜め部材(8)がちょうど収まるように、斜め部材(8)の長尺部(21)および短尺部(22)の寸法が微調整されることを意味している。
【００４３】
このような条件が確保されることにより、折畳み初期段階で各斜め部材の下端部回動中心が互いに離れる方向に移動するようになっており、天板をある程度二つ折りにしない限り折り作業台全体が折り畳まれることはなく、使用中のロックが果たされている。したがって、例えば使用状態の作業台を横にして支柱を持って運搬するときであっても、作業台が自重で不用意に閉じてしまうようなことはない。
【図面の簡単な説明】
【図１】この発明による作業台を示す斜視図である。
【図２】この発明による作業台の使用状態の側面図である。
【図３】この発明による作業台の格納状態の側面図である。
【図４】二つ折れ天板の要部を示す拡大斜視図である。
【図５】天板が二つ折れに畳まれる途中状態を示す拡大断面図である。
【図６】天板と支柱との結合部分を示す拡大斜視図である。
【図７】図６のVII-VII線に沿う断面図である。
【図８】図６のVIII-VIII線に沿う断面図である。
【図９】斜め部材の詳細な構成を示す拡大斜視図である。
【図１０】収納金具の詳細な構成を示す拡大斜視図である。
【図１１】同拡大断面図である。
【図１２】この発明による作業台の折畳み途中の状態を示す側面図である。
【符号の説明】
(1) 前脚
(2) 後脚
(3) 左右支柱
(4) 踏桟
(5) 天板
(6) 天板受け桟
(6a) 円弧状上面
(7) 連結金具
(8) 斜め部材
(9) 収納金具
(21) 長尺部
(22) 短尺部
(61) 支柱への取付部
(62) カバー部
(63) 天板への取付部 [0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a worktable that can be folded.
[0002]
[Prior art]
As a foldable work table, a stepladder is generally used.
[0003]
[Problems to be solved by the invention]
The conventional stepladder has the convenience of being easily foldable, but has problems such as a small working space and a prohibition of work on a top plate, and its improvement is demanded.
[0004]
An object of the present invention is to provide a worktable which can be easily folded and has excellent workability and safety.
[0005]
Means for Solving the Problems and Effects of the Invention
Workbench according this invention comprises a pair of leg before and after you face under spreading conditions Ri name of at least one踏桟which stopped passing on the left and right struts and between them, is passed between the upper part of the front and rear legs An inverted V-shaped bi-foldable top plate whose front and rear ends are rotatably supported at the upper ends of the front and rear legs, and front and rear top plates provided at the upper ends of each leg to receive the front and rear ends of the top plate and crosspiece receiving a connecting fitting to each other rotatably connected to the front and rear ends of the upper and the top plate of the right and left struts, passed in an X shape between before hind leg, the front and rear legs when the workbench using It is provided with a pair of diagonal members that move so that the front and rear legs come closer to each other when the top plate is folded in an inverted V-shape, and each diagonal member is folded in two in a V-shape. It consists of a long part and a short part that are connected as possible, and the upper and lower ends rotate to the corresponding front and rear legs respectively And the long portions of the respective oblique members are rotatably connected to each other, and the connection center between the upper end of the oblique member and the top receiving tray is A and C, and the lower end of the oblique member. In the initial stage of folding, the connection center between the long portions of the oblique members is A, and the connection center between the long portions and the short portions of the oblique members is E and F. And C move closer and upward, B and D move away from each other and upward, and E and F move closer to each other and downward .
[0006]
According to a workbench of this invention, along with a wide work area on the top plate is secured, rotation of the top panel is prevented against the leg before and after the front and rear leg connecting means. Then, after the operation is completed, the top plate is folded in an inverted V-shape so that the oblique members move so that the front and rear legs come close to each other, and the entire worktable is compactly folded.
[0007]
The difference between the distance from the upper end pivot center of the diagonal members to the connecting portion from the center distance and the lower end center of rotation to the connecting portion center, of the other diagonal member from the upper end center of rotation of one of the diagonal member The distance is substantially equal to the distance to the lower end rotation center. In this way, when the top plate is folded in two after the work is completed, the lower end of each oblique member pivots with respect to the tread of the front and rear legs, and the upper end thereof pivots with respect to the top receiving tray. At the same time, the short part of each oblique member rotates with respect to the long part, and the entire worktable is folded compactly.
[0008]
Here, "the difference between the distance from the center of rotation of the upper end portion of each oblique member to the center of the connecting portion and the distance from the center of rotation of the lower end portion to the center of the connecting portion is determined from the center of rotation of the upper end portion of one of the oblique members to the other. Is equal to the distance to the center of rotation of the lower end portion of the oblique member. "Means that AB = CE-BE and CD = AF-DF in FIG. In addition, "substantially" means that, in FIG. 3, the distances of the points A, B, C, D, E, and F from the center plane at the time of folding are not the same, and the center plane at the time of folding of each line is considered. Means that the length of each line segment is finely adjusted so that the distances along are equal.
[0009]
In this specification, “=” is also used in the case of “substantially equal”.
[0010]
Further, in this specification, “can be folded into two in a V shape” means that it can be folded into two in a V shape at an intermediate portion and cannot be folded into two in an inverted V shape. However, "can be folded in an inverted V-shape" means that it is possible to fold it in an inverted V-shape in the middle part and not in a V-shape. These terms are used not only for horizontal members, but also for diagonal members, and when the two-folded part moves upward (directly or obliquely upward), the term "inverted V-shape" is used. It is referred to as "folding in two", and when moving downward (directly or obliquely downward), it is referred to as "folding in a V-shape". A member that can be folded in two in a V-shape can be obtained, for example, by butting two members and connecting them rotatably to each other at the upper edge of the abutting portion. Possible members can be obtained, for example, by abutting two members and pivotally connecting them at the lower edge of the abutment.
[0011]
In worktable of this invention, while being a convex arcuate contour of the front and rear ends of the top plate is viewed from the lateral direction, the upper surface of the receiving top plate crosspieces are formed on the concave arcuate when viewed from the lateral direction In some cases, the front and rear ends of the top plate are guided to the top receiving tray when folded. With this configuration, the load applied to the top plate is supported by the top plate receiving bar, the folding operation can be performed smoothly, and the holding of the work table when opening and closing is prevented.
[0012]
Moreover, consolidated fittings, and attachment to strut fixed to the upper end of the column, and a cover portion covering the upper surface of the contiguous strut attachment to the strut, the left and right sides of the top plate continuous to the cover portion It may consist of a mounting part to the top plate that is rotatably mounted. In this case, the connecting metal covers the upper end surface of the support, and a cover for covering the upper end of the support is not required, so that the number of parts can be reduced.
[0013]
Furthermore, the top plate receiving bar and the predetermined step bar may be provided with storage fittings with which front and rear corresponding members are engaged at the end of folding. The storage fitting can have various configurations.For example, the storage fitting is formed in a substantially U-shape with an opening facing outward in the front-rear direction, and a horizontally projecting engaging claw is provided on an upper edge and a lower edge of a bottom wall thereof. In this state, the engaging claws intersect in a sliding manner with the work table folded. This prevents the legs from moving and rattling in the left and right directions in the folded state (lateral displacement phenomenon), and can be easily transported and stored. In addition, the storage bracket is formed such that the columns are exactly parallel to each other when folded, so that even if a large number of work tables are stacked side by side, they do not collapse.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
[0015]
In this specification, for the front and rear, the right in FIG. 2 is referred to as front, the left is referred to as rear, and the left and right are referred to rear.
[0016]
FIGS. 1 to 12 show a first embodiment of this invention.
[0017]
Workbench according this invention, the right and left struts (3) and struts (3) before and after consisting踏桟(4) of the stop was four stages passed between a pair of legs (1) and (2), inverted V-shaped A top plate (5) that can be folded into two, a front and rear top plate receiving bar (6) provided at the upper end of each leg (1) (2) to receive the front and rear ends of the top plate (5), A connecting bracket (7) for rotatably connecting the upper end of (3) and the front and rear ends of the top plate (5) to each other, the step (4) of the front leg (1), and the rear plate receiving bar (6). And a slanted member (8) passed obliquely between the step (4) of the rear leg (2) and the front top receiving tray (6), the top receiving tray (6) and the predetermined A storage bracket (9) provided on each of the step rails (4) (in this example, at the bottom) is provided so that it can be folded from the use state shown in FIG. 2 to the storage state shown in FIG. ing.
[0018]
Each of the struts (3) and the crosspiece (4) is made of an extruded aluminum material. Each strut (3) is formed in a U-shape in cross section, and has an opening facing inward. Each step (4) is formed in a substantially trapezoidal cross section, and its upper wall (only described in a large view) protrudes inward. Each of the front and rear legs (1) and (2) is slightly spread downward, and the angle between each of the columns (3) and the ground is about 83 °.
[0019]
As shown in detail in FIGS. 4 to 7, the top plate (5) is composed of a pair of front and rear scaffold plates (11) and (12), and a connection side end (rear end) of the front scaffold plate (11) and a rear end. Fixing brackets (13) and (14), which are fixed to the connecting end (front end) of the scaffolding plate (12), and a movable bracket that relatively rotatably connects the fixing brackets (13) and (14). (15), the front and rear covers (16) fixed to the front end of the front scaffold plate (11) and the rear end of the rear scaffold plate (12), and the left and right ends of the movable bracket (15). And left and right cover portions (17) attached to the fixing brackets (13) and (14) by tapping screws (18).
[0020]
The front and rear scaffolding plates (11) and (12) are formed by extruding aluminum in the front and rear direction, and the fixing brackets (13) and (14), the movable bracket (15), and the front and rear cover portions (16) are in the extrusion direction. Are aluminum extrusions in the left-right direction.
[0021]
The front and rear scaffolding plates (11) and (12) include an upper wall serving as a tread portion, left and right walls with inwardly projecting edges, and an intermediate reinforcing wall.
[0022]
Each of the fixing brackets (13) and (14) is formed in a substantially U-shape in cross section, and covers the opening at the connecting end side of the front and rear scaffolding plates (11) and (12), and is combined with the movable bracket (15). It also has the function of constituting hinge means for folding the top plate (5) in half.
[0023]
As shown in detail in FIG. 4 and FIG. 5, a front scaffold plate side hinge structure having a concave groove (32) opened rearward is provided on a lower wall portion of a fixing bracket (13) fixed to the front scaffold plate (11). A rear scaffold plate side hinge component (33) having a concave groove (34) opened forward is provided on a lower wall portion of the fixing bracket (14) in which the portion (31) is fixed to the rear scaffold plate (12). Each is provided. The movable bracket (15) includes a front hinge component (35) rotatably fitted in the concave groove (32) of the front scaffold plate-side hinge component (31), and a rear scaffold plate-side hinge component. And a rear hinge component (36) rotatably fitted in the concave groove (34) of (33).
[0024]
The lower wall portion of the concave groove (32) of the front scaffold plate-side hinge component portion (31) is flat, and a rear edge portion is provided with an engaging portion (37) extending upward. Similarly, the lower wall of the concave groove (34) of the rear scaffold plate-side hinge component (33) is flat, and its front edge is provided with an engaging portion (38) extending upward. . In the concave groove (32) of the front scaffold plate side hinge component (31), a cross-section arc-shaped guide having a size of a quarter circle from the middle of the upper wall to the front edge of the lower wall is provided. A surface is provided, and in the concave groove (34) of the rear scaffold plate side hinge component (33), a size of a quarter circle from the middle of the upper wall to the rear edge of the lower wall is provided. An arcuate guide surface in cross section is provided. The front hinge constituting portion (35) of the movable bracket (15) has a bent portion (39) having a substantially arc-shaped cross section having an outer peripheral surface along the arc-shaped guide surface of the corresponding concave groove (32), and a lower edge thereof. And a rearward-facing hinge-shaped engaging portion (40) continuous with the portion, and the rear hinge component (36) of the movable bracket (15) has an outer peripheral surface along the arc-shaped guide surface of the corresponding concave groove (34). It comprises a bent portion (41) having a substantially arc-shaped cross section and a forwardly-turned engaging portion (42) connected to the lower edge of the bent portion (41). The distal end of each of the folded engagement portions (40) and (42) is formed in an arc shape with a cross section of a half circle, and the engagement portion ( At the base of 37) and 38), a guide surface having an arc-shaped cross section is provided.
[0025]
In addition, each fixing bracket (13) (14) has a C-shaped cross section for attaching the left and right cover parts (17) that prevent the movable bracket (15) from coming off in the left and right direction by tapping screws (18). Tapping screw insertion portions (43) and (44) are formed.
[0026]
The top plate receiving bar (6) is made of an extruded aluminum material and has a substantially rectangular cross section. The top plate receiving bar (6) is bridged between the left and right columns (3) in the same manner as the step bar (4), but its cross-sectional shape is different from that of the step bar (4). That is, as shown in FIG. 6, the upper wall of the top plate receiving bar (6) is formed to have an arc-shaped upper surface (6a) having a concave cross section. This shape is for guiding the front and rear ends of the top plate (5) when folded, and correspondingly, the front and rear ends of the top plate (5), that is, the front and rear cover portions (5) of the top plate (5). 16) is formed as follows.
[0027]
Since the cover part (16) of the top plate (5) has the same shape before and after, the front cover part (16) will be described with reference to FIGS.
[0028]
The front cover part (16) of the top plate (5) has a sliding wall (51) formed in a semicircular cross section from the end of the upper wall of the front scaffold plate (11) to near the end of the lower wall. An upper rivet stop wall (52) extending to the upper end of the sliding wall (51) and extending along the upper wall of the front scaffold plate (11); and an upper rivet stopping plate (52) extending to the lower end of the sliding wall (51). 11) A lower riveting wall (53) extending along the lower wall, and a closing wall (54) connected to the upper end of the sliding wall (51) and extending downward to close the end opening of the front scaffold plate (11). ) And a positioning wall (55) extending from the lower end of the closing wall (54) along the lower wall of the front scaffold plate (11).
[0029]
A connecting bracket (7) connecting the left and right columns (3) and the top plate (5) has a mounting portion (61) to the column fixed with rivets to the upper end of the outer wall of the column (3), A cover (62) connected to the mounting part (61) to the column and covering the upper end surface of the column (3), and a stepped bolt (64) and nut on the side of the top plate (5) connected to the cover (62) (65) and a mounting portion (63) to the top plate rotatably mounted by (65). As shown in FIG. 8, the left-right axis is inserted into the bolt shaft portion insertion hole formed in the mounting portion (63) of the connection fitting (7) to the top plate and the front scaffold plate (11) of the top plate (5). The stepped shaft portion (64a) of the stepped bolt (64) is loosely inserted.
[0030]
As shown in FIG. 7, the concave arc-shaped upper surface (6a) of the top plate receiving bar (6) has a radius substantially equal to the radius of the sliding wall (51) of the front cover portion (16) and approximately 1/4 circle. When the workbench is in use, the lower surface of the sliding wall (51) of the front cover (16) is placed on the top plate receiving bar (6). Therefore, the front scaffold plate (11) of the top plate (5) can rotate clockwise in FIG. 6 around the axis of the stepped bolt (64), and the top plate (5) with respect to the support (3) can be rotated. Can be rotated.
[0031]
Each diagonal member (8) is composed of a long part (21) and a short part (22) connected in a V-shape so as to be foldable in two. The intermediate portions of the long portions (21) of the two oblique members (8) are connected to each other by a connecting pin (23) in an X shape and rotatable with respect to each other.
[0032]
Near the center of the third step from the bottom, a lower support bracket (19) for rotatably supporting the lower end of the short part (22) of each diagonal member (8) is attached. At a position corresponding to (6), an upper support (20) for rotatably supporting the upper end of the elongated portion (21) of each oblique member (8) is attached.
[0033]
The long part (21) of each oblique member (8) is a long square pipe (24), an end connection fitting (25) fitted to the upper end of the square pipe (24), and a square pipe ( Similarly, the short part (22) is fitted to the short square pipe (27) and the upper end of the square pipe (27). Fitted to the butting portion connecting fitting (28) of the elongated portion (21) and the butting portion connecting fitting (28) rotatably connected by the connecting pin (30) and the lower end of the square pipe (27). It consists of the fitted end connection fittings (29).
[0034]
The butting portion connection fitting (26) of the long portion (21) and the butting portion connection fitting (28) of the short portion (22) each have a rectangular tubular main body portion, and the main body portions are butted against each other and It is connected so that it can be folded in two only in the direction of the inverted V-shape. That is, the butt connecting metal fitting (26) of the long part (21) is provided with an ear part (26a) extending upward from the inner wall of the main body part, and the butt connecting metal fitting (28) of the short part (22) is provided. Ear portions (28a) extending upward from the outer wall of the main body portion are provided facing each other, and these ear portions (26a) (28a) are mutually turned by a pin (30) having an axis at the upper edge of the abutting surface. It is movably connected.
[0035]
The end fittings (25) and (29) of the long part (21) and the short part (22) are made of an extruded material that extends in the left-right direction, and have cylindrical parts (25a) and (29a) formed at their ends. I have.
[0036]
The upper support bracket (20) provided on the top plate receiving bar (6) has a U-shaped mounting portion (71) fitted to the top plate receiving bar (6) from below, and a mounting portion (71). And a support portion (72) formed of left and right opposing walls provided inwardly on the inner side wall. The mounting portion (71) is fixed to the top plate receiving bar (6) by fastening a nut to a bolt (73) penetrating the mounting portion (71) and the top plate receiving bar (6). Then, the bolt () penetrating the opposed wall of the support portion (72) of the upper support bracket (20) is formed on the cylindrical portion (25a) of the end bracket (25) of the long portion (21) of each oblique member (8). By loosely inserting the 74), the upper end of the oblique member (8) is rotatable with respect to the top plate receiving bar (6).
[0037]
The lower support bracket (19) provided on the step (4) has a U-shaped mounting part (75) fitted to the step (4) from below, and a lower part of the mounting part (75). It comprises a support portion (76) composed of left and right opposed walls provided on the wall so as to protrude downward. The mounting portion (75) is fixed to the step (4) by fastening a nut to a bolt (77) penetrating the mounting portion (75) and the step (4). Then, bolts (78) penetrating the cylindrical portion (29a) of the end fitting (29) of the short portion (22) of each diagonal member (8) penetrate the opposing wall of the support portion (76) of the lower support fitting (19). ) Is loosely inserted, so that the lower end of the oblique member (8) is rotatable with respect to the step rail (4).
[0038]
As shown in FIGS. 10 and 11, the storage metal fitting (9) is a substantially U-shaped metal fitting having an opening facing outward in the front-rear direction. Claws (9a) and (9b) are provided. The storage fittings (9) are all of the same shape, and the engaging claws (9a) (9b) are fixed to the step (4) of the front leg (1) as shown in FIG. For those that are located on the upper right half of the bottom wall and the lower left half of the bottom wall, and fixed to the step (4) of the rear leg (2), the upper left edge of the bottom wall Located in the right half of the lower edge. Therefore, when the workbench is folded, the upper engaging claws (9a) and the lower engaging claws (9b) intersect each other in a rubbing manner, as shown in FIG. The legs (1) and (2) are prevented from shifting left and right. Also, in this folded state, the butting surfaces of the storage brackets (9) are parallel to the length direction of the column (3). Therefore, in the folded state shown in FIG. 3, a space for accommodating the oblique member (8) is maintained between the columns (3), and lateral displacement during transportation / storage is prevented.
[0039]
In the working table described above, in use, the front scaffold plate (11) and the rear scaffold plate (12) of the top plate (5) abut against each other, and the long portion (21) and the short portion ( 22) is matched. As shown in FIG. 5, the top plate (5) is folded in an inverted V-shape with the lower edge portion of the abutting surface of the front scaffold plate (11) and the rear scaffold plate (12) as the center of rotation. It is possible, but it is not possible to fold it into a V-shape, and the load on the top plate (5) is firmly secured by the top plate (5), the front and rear legs (1) (2), and the oblique member (8). It is accepted. Since the force of the front and rear legs (1) and (2) to spread each other acts in the direction in which the diagonal member (8) tries to fold the inverted V-shape, the diagonal member (8) is ) (2) has an opening preventing function that prevents each other from trying to open.
[0040]
This workbench is folded as follows. In the following description, A and C denote the connection center (the axis of the bolt (74)) between the upper end of the oblique member (8) and the top plate receiving bar (6), and B and D denote the oblique member (8). E and F denote the connection center (the axis of the bolt (78)) of the lower end of the step rail (4) to the connection center (pin (78)) of the long part (21) and short part (22) of the oblique member. 30)).
[0041]
Since the top plate (5) can be folded in two in an inverted V shape as described above, first, the top plate (5) is folded in an inverted V shape as shown by a solid line in FIG. Each diagonal member (8) can be folded in two in a V-shape around the upper edge of the abutting surface of the long part (21) and the short part (22) as the center of rotation (see FIG. 9). , V-shaped. At this time, the front and rear legs (1) and (2) first move from the chain line in FIG. 12 to the solid line (the direction in which they spread). That is, A and C move closer to each other and move upward with respect to the connection center (the axis of the connection pin (23)) between the long portions (21) of the oblique member (8), and B and D Moving away and upwards, E and F approach each other and move downwards. When the top plate (5) is further folded from the state shown in FIG. 12, the front and rear legs (1) and (2) approach each other, and finally, as shown in FIG. 3, the short portion (22) becomes longer. The short part (22) is turned 180 ° with respect to the long part (21), and the short part (22) is stored in a position parallel to the support (3) below the third step from the bottom, and the long part (21) The lower end overlaps the short part (22), and the long parts (21) of the two oblique members (8) are overlapped on the left and right sides and housed between the front and rear legs (1) and (2). A notch (4a) is provided in a portion of the step (4) that interferes with the oblique member (8) (see FIGS. 1 and 9).
[0042]
In the above, as shown in FIG. 3, the condition for folding compactly is that the distance from the upper end rotation centers A and C of the respective oblique members (8) to the connection part centers F and E (the line segment AF and the line segment AE). (Equivalent to the length of the long portion (21)) and the distance from the lower end rotation centers D and B of the respective oblique members (8) to the connection center F and E (line segment DF). And the length of the line segment BE, which is equivalent to the length of the short portion (22)) is different from the rotation centers A and C at the upper end of one of the oblique members (8). (8) Distance to lower end rotation centers B and D (the length of line segment AB and line segment CD, which corresponds to the length along the column (3) of the entire diagonal member (8)) ) Are substantially equal to each other. That is, line segment AB = line segment CD ≒ line segment CE−line segment BE = line segment AF−line segment DF. Here, the points A and B are located near the center of symmetry of the folded state, the points E and F are respectively located on the rear surface of the front strut and the front surface of the rear strut slightly outside thereof, and , Point B and point E are positioned so as to overlap the further outer struts. The above “substantially equal” means that the points A, B, C, D, E, and F in FIG. This means that the dimensions of the long part (21) and the short part (22) of the diagonal member (8) are finely adjusted so that the diagonal member (8) just fits between the two.
[0043]
By ensuring such conditions, the lower end rotation centers of the oblique members move in the direction away from each other at the initial stage of folding, and unless the top plate is folded in two to some extent, the entire folding work table Is not folded and the lock in use is fulfilled. Therefore, for example, even when the work table in use is transported while holding the support sideways, the work table is not inadvertently closed by its own weight .
[Brief description of the drawings]
1 is a perspective view of a workbench according to the invention of this.
FIG. 2 is a side view of a working platform of the use state by the inventors of this.
3 is a side view of the workbench of a storage state by the inventors of this.
FIG. 4 is an enlarged perspective view showing a main part of a two-fold top plate.
FIG. 5 is an enlarged cross-sectional view showing a state where the top plate is being folded in two.
FIG. 6 is an enlarged perspective view showing a joint portion between a top plate and a support.
FIG. 7 is a sectional view taken along the line VII-VII in FIG. 6;
FIG. 8 is a sectional view taken along the line VIII-VIII in FIG.
FIG. 9 is an enlarged perspective view showing a detailed configuration of the oblique member.
FIG. 10 is an enlarged perspective view showing a detailed configuration of a storage metal fitting.
FIG. 11 is an enlarged sectional view of the same.
12 is a side view of the platform of the folding of the middle state by the inventors of this.
[Explanation of symbols]
(1) Front legs
(2) Rear leg
(3) Left and right supports
(4) Step
(5) Top plate
(6) Top plate receiving bar
(6a) Arc-shaped upper surface
(7) Connection bracket
(8) Diagonal member
(9) Storage bracket
(21) Long section
(22) Short section
(61) Attachment part to support
(62) Cover
(63) Mounting part to top plate

Claims

Left and right strut (3) and at least one踏桟(4) opposite to that pair of front and rear legs from-than under spreading conditions was stopped passing between them (1) (2), front and rear legs (1) ( the front and rear ends passed in between the upper end portion front and rear legs 2) (1) (inverted V-shape in two foldable top plate pivotally supported on the upper end of 2) (5), each leg (1) between the front and rear top board receiving the bars provided on the upper portion receiving the front and rear ends of the top plate (5) (2) (6), the upper end portions of the left and right strut (3) and top plate (5) the connecting plate (7) to each other rotatably connected to the front and rear ends, passed before hind leg (1) (2) X-shape between the front and rear when the workbench using the leg (1) (2 open performs stop of) the top plate (5) back and forth leg when was reversed V-shape folded in two (1) (2) and a pair of oblique members (8) to move closer to each other to each other and, each diagonal member (8), the double foldable linked arm member in a V-shape (21) and the shorter part made of (22), upper and lower ends thereof There are together is rotatably supported on the corresponding longitudinal leg (1) (2) are rotatably connected to each other elongate member (21) of the respective diagonal member (8), oblique member ( A and C are the connection centers of the upper end of 8) and the top plate receiving bar (6) , B and D are the connection centers of the lower end of the diagonal member (8) and the step bar (4), and the long of the diagonal member. In the initial stage of folding , A and C are mutually connected on the basis of the connection center between the long portions (21) of the oblique member (8) at the initial stage of folding, assuming that the connection centers of the portion (21) and the short portion (22) are E and F. A workbench adapted to move closer and upward, B and D move away from each other and upward, and E and F move closer to each other and downward .

The contour shape of the front and rear ends of the top plate (5) is a convex arc shape when viewed from the left and right directions, and the upper surface (6a) of the top plate receiving bar (6) is formed into a concave arc shape when viewed from the left and right directions. The work table according to claim 1, wherein the front and rear ends of the top plate (5) are guided to the top plate receiving bar (6) when folded.

Consolidated bracket (7), struts (3) attachment to the strut fixed to the upper end of the (61), a cover portion for covering the upper end face of the pillar continuous with attachment to the strut (61) (3) 3. A top plate (5) according to claim 1 or 2 , further comprising a mounting portion (63) connected to the cover portion (62) and rotatably mounted on the left and right side portions of the top plate (5). Workbench.

The top plate receiving crosspiece (6) and a predetermined踏桟(4), workbench of claim 1 to 3 for housing fittings each other corresponds to the front and rear at the folding end engages (9), respectively.