JPH04371497A - Multistage type elevating device - Google Patents
Multistage type elevating deviceInfo
- Publication number
- JPH04371497A JPH04371497A JP17313591A JP17313591A JPH04371497A JP H04371497 A JPH04371497 A JP H04371497A JP 17313591 A JP17313591 A JP 17313591A JP 17313591 A JP17313591 A JP 17313591A JP H04371497 A JPH04371497 A JP H04371497A
- Authority
- JP
- Japan
- Prior art keywords
- cylinder
- stage
- tube body
- screw
- tube
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 230000003028 elevating effect Effects 0.000 title claims abstract 5
- 230000002093 peripheral effect Effects 0.000 claims abstract description 5
- 230000000717 retained effect Effects 0.000 abstract 1
- 239000003638 chemical reducing agent Substances 0.000 description 2
- 230000010363 phase shift Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
Landscapes
- Forklifts And Lifting Vehicles (AREA)
- Types And Forms Of Lifts (AREA)
Abstract
Description
【０００１】0001
【産業上の利用分野】本発明は、ねじジャッキを利用し
た多段式昇降装置に関し、特に低い揚程から高い揚程ま
で広い範囲で種々の揚程が求められる場合に適した多段
式昇降装置に関するものである。[Field of Industrial Application] The present invention relates to a multi-stage lifting device using a screw jack, and in particular to a multi-stage lifting device suitable for cases where various lifts are required over a wide range from low lifts to high lifts. .
【０００２】0002
【従来の技術】従来、大きな揚程を得るためにねじジャ
ッキを多段式にした昇降装置は知られている（例えば、
特公昭５２−１７８７号、特公昭５７−５４４４０号及
び実公昭５２−６１４８号公報参照）。[Prior Art] Lifting devices using multi-stage screw jacks in order to obtain a large lifting height have been known (for example,
(See Japanese Patent Publication No. 52-1787, Japanese Patent Publication No. 57-54440, and Japanese Utility Model Publication No. 52-6148).
【０００３】0003
【発明が解決しようとする課題】しかし、上記従来の多
段式昇降装置はいずれも、各段ごとに雄ねじと雌ねじを
螺合したねじジャッキの機構を用いているので、製作費
が非常に高くつく。しかも、揚程が大きい場合には、昇
降動作に長い時間がかかり、迅速な高さ調整が困難で作
業性の点でも問題があった。[Problems to be Solved by the Invention] However, all of the above conventional multi-stage lifting devices use a screw jack mechanism in which a male thread and a female thread are screwed together for each stage, so the manufacturing cost is extremely high. . Moreover, when the lift height is large, it takes a long time to move up and down, making it difficult to quickly adjust the height, which poses problems in terms of workability.
【０００４】本発明は上記従来の問題点に鑑みなされた
もので、昇降手段として１段のねじジャッキを用いなが
ら、多段の揚程が得られるように工夫することによって
、安価に製作できると共に、大きな揚程でも高さの調整
が容易、かつ迅速に行なえる多段式昇降装置を提供する
ことを目的とする。The present invention has been developed in view of the above-mentioned conventional problems, and by using a single-stage screw jack as a lifting means and devising a multi-stage lifting height, it can be manufactured at low cost and has a large size. It is an object of the present invention to provide a multi-stage lifting device that can easily and quickly adjust the height even in the lift range.
【０００５】[0005]
【課題を解決するための手段】上記目的を達成するため
に、本発明は、外筒の中心に配設して回転駆動するねじ
軸と、前記ねじ軸に螺合して前記外筒内を上下移動する
回り止めされた雌ねじ体と、前記雌ねじ体に固設した第
１段筒体とを備えているねじ式昇降装置において、前記
第１段筒体内に順次外径が縮小する複数の第２，第３…
筒体を同心状に、かつ互いに上下移動自在に嵌装すると
共に、最も内側の前記筒体の上端に支持頭部を設け、さ
らに、前記各筒体をその外側に隣接する前記筒体に対し
て上昇した位置で停止保持させる係止保持手段を設けた
ことを特徴とする。[Means for Solving the Problems] In order to achieve the above object, the present invention provides a screw shaft disposed at the center of an outer cylinder and driven to rotate; In a screw-type lifting device that includes a female threaded body that is prevented from rotating and moves up and down, and a first stage cylindrical body fixed to the female threaded body, a plurality of cylinders whose outer diameters are sequentially reduced are arranged in the first stage cylindrical body. 2, 3rd...
The cylinders are fitted concentrically and vertically movably relative to each other, and a support head is provided at the upper end of the innermost cylinder, and each cylinder is connected to the cylinder adjacent to the outside thereof. The invention is characterized in that it is provided with a locking and holding means for stopping and holding at the raised position.
【０００６】[0006]
【作用】上記構成において、揚程が低い場合には、ねじ
ジャッキによる前記第１段筒体の昇降動作だけで所定の
高さに調整する。[Operation] In the above structure, when the lifting height is low, it is adjusted to a predetermined height simply by raising and lowering the first stage cylinder using a screw jack.
【０００７】揚程が高くなると、まず最も内側の前記筒
体を手動操作で上昇位置まで引き上げ、前記係止保持手
段により上昇位置に停止保持させたのち、上記同様に前
記第１段筒体の昇降動作によって所定の高さに調整する
。更に、揚程を高くする場合には、前記筒体を順次上昇
位置まで引き上げ、前記係止保持手段により上昇位置に
停止保持させたのち、前記第１段筒体をねじジャッキに
より昇降させて高さを調整する。When the lift height increases, the innermost cylinder is first manually pulled up to the raised position, and then stopped and held at the raised position by the locking and holding means, and then the first stage cylinder is raised and lowered in the same manner as described above. Adjust to the specified height by movement. Furthermore, when increasing the lifting height, the cylinders are sequentially pulled up to the raised position and held at the raised position by the locking and holding means, and then the first stage cylinder is raised and lowered by a screw jack to increase the height. Adjust.
【０００８】[0008]
【実施例】以下、本発明の実施例を図面に基づいて説明
する。Embodiments Hereinafter, embodiments of the present invention will be explained based on the drawings.
【０００９】図１は、本発明に係る多段式昇降装置の最
も縮小した状態を示している。１は基台、２は基台１に
固着立設した外筒、３は外筒２の中心に配設したねじ軸
で、下端部が基台１に固装したウォーム減速機４のウォ
ーム歯車５に嵌挿して連動連結されている。ウォーム歯
車５に噛合するウォーム６は、一端に連設した軸（図示
せず）が外筒２から突出し、図示しない電動回転工具そ
の他の駆動装置に連結して回転駆動されるようになって
いる。FIG. 1 shows the multistage lifting device according to the invention in its most reduced state. 1 is a base, 2 is an outer cylinder fixed and erected on the base 1, 3 is a screw shaft arranged at the center of the outer cylinder 2, and the lower end is a worm gear of a worm reducer 4 fixed to the base 1. 5 and are interlocked and connected. The worm 6 that meshes with the worm gear 5 has a shaft (not shown) connected to one end thereof that protrudes from the outer cylinder 2, and is connected to an electric rotary tool or other drive device (not shown) to be rotationally driven. .
【００１０】ねじ軸３には外周面が外筒２の内周面に摺
接する雌ねじ体７が螺合し、該雌ねじ体７に第１段筒体
８がボルトなどの固定具を用いて固設され、外筒２と同
心状に配置されている。第１段筒体８は外周面に軸方向
に延びるキー溝９を有し、該キー溝９に係合するキー１
０が外筒２の上端開口に固装したカバー１１に固着され
ている。したがって、第１段筒体８は外筒２に対し回り
止めされ、軸方向にのみ移動可能となっている。その結
果、第１段筒体８を固設した雌ねじ体７も外筒２に対し
て回り止めされ、ねじ軸３の回転に連動して第１段筒体
８が外筒２内を上下移動するねじジャッキを構成してい
る。A female screw body 7 whose outer circumferential surface is in sliding contact with the inner circumferential surface of the outer cylinder 2 is screwed onto the screw shaft 3, and a first stage cylinder body 8 is fixed to the female screw body 7 using a fixing device such as a bolt. and is arranged concentrically with the outer cylinder 2. The first stage cylindrical body 8 has a key groove 9 extending in the axial direction on its outer peripheral surface, and the key 1 engages with the key groove 9.
0 is fixed to a cover 11 fixed to the upper end opening of the outer cylinder 2. Therefore, the first stage cylinder 8 is prevented from rotating relative to the outer cylinder 2, and is movable only in the axial direction. As a result, the female screw body 7 to which the first stage cylinder body 8 is fixed is also prevented from rotating relative to the outer cylinder 2, and the first stage cylinder body 8 moves up and down within the outer cylinder 2 in conjunction with the rotation of the screw shaft 3. It consists of a screw jack.
【００１１】第１段筒体８には第２筒体１２が摺接状態
に嵌挿され、該第２筒体１２に第３筒体１３が摺接状態
に嵌挿されている。A second cylinder 12 is fitted into the first cylinder 8 in a sliding manner, and a third cylinder 13 is fitted into the second cylinder 12 in a sliding manner.
【００１２】第２筒体１２の外周面には、上端から下方
に向けて軸方向に長く延びる１本の回り止めキー１４と
、その下方において周方向に１２０度位相をずらせて配
置した３つの荷重受けキー１５が固着突設されている（
図２参照）。荷重受けキー１５は、後述するように第２
筒体１２を手動操作で持ち上げたとき、第１段筒体８の
上端に固着したリング状のカバー１６の内周面に１２０
度位相をずらせて設けた３つのキー溝１７に係合して上
方へ通過し得るようになっている。一方、回り止めキー
１４はキー溝１７の１つに係合して、第２筒体１２が第
１段筒体８に対して回転するのを阻止している。On the outer circumferential surface of the second cylindrical body 12, there is one detent key 14 extending in the axial direction downward from the upper end, and three detent keys arranged below the detent key 14 with a phase shift of 120 degrees in the circumferential direction. A load receiving key 15 is fixed and protruded (
(see Figure 2). The load receiving key 15 is a second
When the cylindrical body 12 is lifted manually, the inner peripheral surface of the ring-shaped cover 16 fixed to the upper end of the first stage cylindrical body 8
It engages with three key grooves 17 provided at different degrees of phase so that it can pass upward. On the other hand, the detent key 14 engages with one of the keyways 17 to prevent the second cylindrical body 12 from rotating relative to the first stage cylindrical body 8 .
【００１３】第３筒体１３の外周面には、その下部にお
いて周方向１２０度位相をずらせて配置した３つの荷重
受けキー１８が固着突設されている（図２参照）。荷重
受けキー１８は、後述するように第３筒体１３を手動操
作で持ち上げたとき、第２筒体１２の上端に固着したリ
ング状のカバー２０の内周面に１２０度位相をずらせて
設けた３つのキー溝２１に係合して上方へ通過し得るよ
うになっている。Three load receiving keys 18 are fixedly and protrudingly provided on the outer peripheral surface of the third cylinder 13 at the lower part thereof and are arranged 120 degrees out of phase in the circumferential direction (see FIG. 2). As will be described later, when the third cylindrical body 13 is manually lifted, the load receiving key 18 is provided on the inner circumferential surface of the ring-shaped cover 20 fixed to the upper end of the second cylindrical body 12 with a phase shift of 120 degrees. It can be engaged with three key grooves 21 and passed upward.
【００１４】一方、カバー１６の上面には図２に示すよ
うに、荷重受けキー１５に対応する３つの係合溝２２が
キー溝１７に対して周方向に一定角度（図示の例では４
５度）位相をずらせて設けられている。同様にカバー２
０の上面には荷重受けキー１８に対応する３つの係合溝
２３がキー溝２１に対して周方向に一定角度（４５度）
位相をずらせて設けられている第２筒体１２のカバー２
０には手動操作で持ち上げるための把手２４が取り付け
られている。一方、第３筒体１３は上端開口に支持ヘッ
ド２５を嵌着し、該ヘッド２５に把手２６と外筒２の上
方まで覆う保護カバー２７が取り付けられている。
次に、上記構成を有する多段式昇降装置の作動について
説明する。On the other hand, as shown in FIG. 2, on the upper surface of the cover 16, three engaging grooves 22 corresponding to the load receiving keys 15 are formed at a constant angle in the circumferential direction with respect to the key groove 17.
5 degrees) out of phase. Similarly cover 2
Three engaging grooves 23 corresponding to the load receiving keys 18 are formed on the upper surface of the 0 at a constant angle (45 degrees) in the circumferential direction with respect to the key groove 21.
Cover 2 of the second cylindrical body 12 provided out of phase
0 is attached with a handle 24 for manual lifting. On the other hand, the third cylindrical body 13 has a support head 25 fitted into its upper opening, and a protective cover 27 that covers the handle 26 and the outer cylinder 2 is attached to the head 25.
Next, the operation of the multistage lifting device having the above configuration will be explained.
【００１５】揚程が低い場合には、図３に示すように、
ねじ軸３の回転運動を雌ねじ体７の軸方向運動に変換す
るねじジャッキの機構によって第１段筒体８を昇降させ
、支持ヘッド２５を所定の高さに調整する。When the head is low, as shown in FIG.
A screw jack mechanism that converts the rotational movement of the screw shaft 3 into an axial movement of the female threaded body 7 moves the first stage cylinder 8 up and down, and adjusts the support head 25 to a predetermined height.
【００１６】次に、揚程が高い場合には、、図１に示す
最下降位置において、先ず、最も内側の第３筒体１３を
手動操作により把手２６を把持し上昇位置まで持ち上げ
、荷重受けキー１８をキー溝２１を通じて上方に移動さ
せた後、第３筒体１３を周方向へ４５度回転変位させ、
荷重受けキー１８を係合溝２３に係合させることによっ
て上昇位置に停止保持させる。続いて、上記同様にねじ
軸３の回転運動を雌ねじ体７の軸方向運動に変換するね
じジャッキの機構により第１段筒体８を昇降させ、支持
ヘッド２５を所定の高さに調整する（図４参照）。Next, when the lifting height is high, at the lowest position shown in FIG. 18 upward through the keyway 21, the third cylindrical body 13 is rotated by 45 degrees in the circumferential direction,
By engaging the load receiving key 18 with the engagement groove 23, it is stopped and held in the raised position. Subsequently, in the same manner as described above, the first stage cylindrical body 8 is raised and lowered by the mechanism of the screw jack that converts the rotational movement of the screw shaft 3 into the axial movement of the female threaded body 7, and the support head 25 is adjusted to a predetermined height ( (See Figure 4).
【００１７】さらに揚程を高くする場合には、第２筒体
１２を上述した第３筒体１３と同様に手動操作により把
手２４を把持し上昇位置まで持ち上げ、荷重受けキー１
５をキー溝１７から離脱させたのち、第２筒体１２を周
方向へ４５度回転変位させ、荷重受けキー１５を係合溝
２２に係合させることによって上昇位置に停止保持させ
る。このように第２筒体１２及び第３筒体１３を上昇位
置に係止保持させた状態で、上記同様にねじ軸３の回転
運動を雌ねじ体７の軸方向運動に変換するねじジャッキ
の機構により第１段筒体８を昇降させ、支持ヘッド２５
を所定の高さに調整するのである。If the lifting height is to be further increased, the handle 24 of the second cylindrical body 12 is manually held in the same way as the third cylindrical body 13 described above, and the handle 24 is lifted to the raised position, and the load receiving key 1 is lifted.
5 is removed from the key groove 17, the second cylindrical body 12 is rotated by 45 degrees in the circumferential direction, and the load receiving key 15 is engaged with the engagement groove 22 to be stopped and held in the raised position. With the second cylindrical body 12 and the third cylindrical body 13 locked and held in the raised position in this way, the mechanism of the screw jack converts the rotational movement of the screw shaft 3 into the axial movement of the female threaded body 7 in the same manner as described above. The first stage cylindrical body 8 is raised and lowered by the supporting head 25.
is adjusted to a predetermined height.
【００１８】[0018]
【発明の効果】以上説明したように、本発明の多段式昇
降装置は、１段のねじジャッキによる昇降機構を備えて
いるだけでありながら、多段式のねじジャッキと同等の
大きな揚程が得られる。しかも、揚程の大幅な変更は第
２，３…の筒体を順次上昇位置まで持ち上げて行なった
のち、前記ねじジャッキによる第１段筒体の昇降動作に
よって微細な調整を行なうようにしたから、高い揚程の
変更調整が迅速にできる。したがって、低い揚程から高
い揚程まで広い範囲に亘って種々の高さが要求される船
体ブロックの支持装置として好適である。[Effects of the Invention] As explained above, although the multi-stage lifting device of the present invention is equipped with a lifting mechanism using only one stage screw jack, it can obtain a large lifting height equivalent to that of a multi-stage screw jack. . Moreover, a large change in lift height is made by lifting the second, third, etc. cylinders one after another to the raised position, and then fine adjustments are made by raising and lowering the first stage cylinder using the screw jack. High lift height can be quickly adjusted. Therefore, it is suitable as a support device for hull blocks that require various heights over a wide range from low lifting heights to high lifting heights.
【００１９】また、ねじジャッキ昇降機構は１段だけで
あるから、多段式のねじジャッキを用いた装置に比べて
安価に製作できる。Furthermore, since the screw jack lifting mechanism has only one stage, it can be manufactured at a lower cost than a device using a multi-stage screw jack.
【図１】本発明に係る多段式昇降装置の一部縦断正面図
である。FIG. 1 is a partially vertical front view of a multi-stage lifting device according to the present invention.
【図２】同要部の平面図である。FIG. 2 is a plan view of the main parts.
【図３】及び[Figure 3] and
【図４】それぞれ使用状態を示す一部縦断正面図である
。FIG. 4 is a partially longitudinal front view showing the state of use.
１ 基台 ２ 外筒 ３ ねじ軸 ４ ウォーム減速機 ７ 雌ねじ体 ８ 第１段筒体 ９ キー溝 １０ キー １２ 第２筒体 １３ 第３筒体 １５，１８ 荷重受けキー １６，２０ カバー １７，２１ キー溝 ２２，２３ 係合溝 ２４，２６ 把手 ２５ 支持ヘッド 1 Base 2 Outer cylinder 3 Screw shaft 4 Worm reducer 7 Female threaded body 8 First stage cylinder 9 Keyway 10 key 12 Second cylinder 13 Third cylinder 15, 18 Load receiver key 16,20 Cover 17, 21 Keyway 22, 23 Engagement groove 24, 26 Handle 25 Support head
Claims (2)
じ軸と、前記ねじ軸に螺合して前記外筒内を上下移動す
る回り止めされた雌ねじ体と、前記雌ねじ体に固設した
第１段筒体とを備えているねじ式昇降装置において、前
記第１段筒体内に順次外径が縮小する複数の第２，第３
…筒体を同心状に、かつ互いに上下移動自在に嵌装する
と共に、最も内側の前記筒体の上端に支持頭部を設け、
さらに、前記各筒体をその外側に隣接する前記筒体に対
して上昇した位置で停止保持させる係止保持手段を設け
たことを特徴とする多段式昇降装置。1. A screw shaft disposed at the center of an outer cylinder and driven to rotate; a female threaded body that is screwed onto the screw shaft and moves up and down inside the outer cylinder, and is fixed to the female screw body. In the screw type lifting device, the first stage cylinder has a plurality of second and third cylinders whose outer diameters are sequentially reduced.
...the cylinders are fitted concentrically and movably up and down each other, and a support head is provided at the upper end of the innermost cylinder,
The multi-stage elevating device further includes a locking and holding means for stopping and holding each cylinder at a position raised relative to the cylinder adjacent to the outside thereof.
周面に周方向に定間隔をおいて設けた複数の荷重受けキ
ーと、前記各筒体の上端面に前記荷重受けキーに対応し
て周方向に間隔をおいて設けた係合溝とから成り、前記
各筒体を、その外側に隣接する前記筒体に対して上昇し
た位置まで移動させたのち、回転変位させて、前記荷重
支持キーを前記係合溝に係合することにより、上昇位置
に停止保持させるように構成されている請求項１記載の
多段式昇降装置。2. The locking and holding means includes a plurality of load receiving keys provided at regular intervals in the circumferential direction on the outer peripheral surface of each of the cylindrical bodies, and a plurality of load receiving keys provided on the upper end surface of each of the cylindrical bodies. and engaging grooves provided at corresponding intervals in the circumferential direction, and each cylinder is moved to a position raised relative to the cylinder adjacent to the outside thereof, and then rotationally displaced; The multi-stage lifting device according to claim 1, wherein the load support key is stopped and held in the raised position by engaging with the engagement groove.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP17313591A JPH04371497A (en) | 1991-06-18 | 1991-06-18 | Multistage type elevating device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP17313591A JPH04371497A (en) | 1991-06-18 | 1991-06-18 | Multistage type elevating device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH04371497A true JPH04371497A (en) | 1992-12-24 |
Family
ID=15954771
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP17313591A Pending JPH04371497A (en) | 1991-06-18 | 1991-06-18 | Multistage type elevating device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH04371497A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07172783A (en) * | 1993-12-22 | 1995-07-11 | Mitsubishi Electric Corp | Jack |
| JP2013543467A (en) * | 2010-10-05 | 2013-12-05 | ホワイティング・コーポレーション | Lift bracket assembly including screw jack connector |
| JP2020189739A (en) * | 2019-05-23 | 2020-11-26 | 株式会社Ａｏｉ | Support tool and deck plate support tool |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02159404A (en) * | 1988-12-12 | 1990-06-19 | K & M Enterp Kk | Freely expandable support device |
-
1991
- 1991-06-18 JP JP17313591A patent/JPH04371497A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02159404A (en) * | 1988-12-12 | 1990-06-19 | K & M Enterp Kk | Freely expandable support device |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07172783A (en) * | 1993-12-22 | 1995-07-11 | Mitsubishi Electric Corp | Jack |
| JP2013543467A (en) * | 2010-10-05 | 2013-12-05 | ホワイティング・コーポレーション | Lift bracket assembly including screw jack connector |
| JP2020189739A (en) * | 2019-05-23 | 2020-11-26 | 株式会社Ａｏｉ | Support tool and deck plate support tool |
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