JPH0647971Y2 - Manhole ladder - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a portable ladder for elevating and lowering for workers to enter and leave a manhole or other underdrain for work.

[Conventional technology]

Generally, ladders are used for inspecting the inside of manholes, cleaning work and repair work for cables etc.,
Apart from the fact that manholes are always equipped with ladders, for crime prevention and other reasons, manholes without ladders are used by dropping the carried ladders or leaning against them.

[Problems to be solved by the invention]

However, since the manhole is relatively narrow, a lightweight and compact ladder is required for handling, and various portable ladders have been proposed, but if the manhole lid is removed, there is only a receiving frame for the manhole lid. It is unstable because it slips or swings just by leaning the ladder against the peripheral wall of the opening, and when the hole is deep, the ladder cannot be used due to the insufficient length of the ladder. The procedure was also different, and there was a problem in handling such that another worker pressed the top end of the ladder that had come out of the opening to the surface and went up and down.

The present invention is intended to properly eliminate these conventional drawbacks.A ladder for raising and lowering can be fixed even in manholes with various dimensional differences, and a ladder that is extremely lightweight and easy to handle can be set without swinging or misalignment. It is intended to be provided in a simple and inexpensive form.

[Means for solving problems]

The present invention is a ladder A in which treads 21 are appropriately provided on both sides of a column 20.
In the supporting rail 22 on one side of the support column 20 is provided, the slide post 20 ₁ provided with the guide groove 23 of the slide to be fitted with slidably provided on the rail 22, the sliding strut 2
A lock engaging piece 24 that can be engaged with and disengaged from the tread 21 at 0 ₁ is pivotally attached to the support column 20 of the ladder A by a support shaft 26 and has an arm 3 that can be attached to and detached from the manhole cover receiving frame C. is a bracket 2 for mounting support those fixed deployed above the sliding strut 20 _1.

Ladder A manhole during After locking in wearing the length corresponding to the manhole depth stretching engaging piece 24 of the slide column 20 ₁ to踏棧21 stopper 28 when installing a ladder A manhole in this ladder groove D which is placed the arm 3, 3 in the bracket 2 which is fixed to the slide support 20 ₁ to receiving frame C for the manhole cover opens to pivot about a pivot portion 4
The bracket 5 is fixed to the manhole while the hooks 5 and 5 are fitted and held therein and the arms 3 and 3 are stretched, and the ladder A can be set in the manhole opening without slipping and used.

Further, when removing the ladder, if the slide pillar 20 ₁ is pulled up along the pillar 20 and the ladder A is lifted, the hooks 5 and 5 ₁ of the bracket 2 and the arm 3 are pulled out from the concave groove D of the manhole cover receiving frame C. Can be carried.

〔Example〕

An embodiment of the present invention will be described with reference to the drawings. In a ladder A in which treads 21 are appropriately provided on both sides of a support 20, a support rail 22 is provided on the support 20 and a slide for fitting to the rail 22 is provided. The slide column 20 ₁ provided with the guide groove 23 is slidably provided, and the locking piece 24 for locking and disengaging the tread 21 on the slide column 20 ₁ is attached to the column 20 of the ladder A by the support shaft 26.
In rotatably pivoted, and is a bracket 2 for mounting support having an arm 3 which can be attached to and detached from the manhole cover receiving frame C that fixed deployed above the sliding strut 20 _1.

The support column 20 is a single support column with a fixed support column 20 having a leg member 25 at the lower end thereof, and a guide groove 23 fitted to the rails 22, 22 arranged opposite to one side of the upper end of the fixed support column 20. As an expansion / contraction ladder A composed of slide columns 20 ₁ slidably connected to each other, a flexible cord 29, for example, a pulling rope is connected and interposed between the slide columns 20 ₁ and 20. Each strut 20 because this rail 22 and the guide groove 23 in a relative relationship, provided Elect slide column 20 _1.

The locking piece 24 is rotatably pivotally attached to the pair of fixed columns 20 by a support shaft 26, and is biased in one direction by a coil spring.
Wherein a notch 27 for locking the slide posts 20 ₁踏棧21, Yes and a stopper 28 for opening and closing the notch 27 and the bracket 2 is pivotally pivot the arm 3 at pivot portions 4 Hooks 5, 5 _{1 which} are attached to the bracket 2 and the arm 3 and can be fitted into the recessed grooves D formed in the receiving frame C for the manhole lid.
Although it is fixed to the support column 20, a pair of the support pieces 1 are provided on the bracket 2 as a detachable detachable type so that the support pieces 1 face each other and the tread 21 of the ladder A is fitted therein. It is also possible to adopt a mode in which a receiving plate or a chucking mechanism which has a notch groove 10 that engages with each other to facilitate the attachment and detachment of the ladder A is attached.

Incidentally, as the bracket 2 consists of a U-shaped channel member, there is provided with a hook 5 ₁ as a leg, which was bent at both ends at a predetermined angle, the arm 3 at its ends, 3 are connected and connected. Also, this arm 3
Wherein provided in pairs in the vicinity of both ends of the bracket 2, is deployed freely possible open leg folded, pivot portion 4 through a bush 4 ₁
A coil spring (not shown) is wound around the pivotal support portion 4 if necessary so that it can be clamped and supported by the manhole cover receiving frame C as an automatic return structure for urging in the folding direction. It is also effective to do so, and depending on the use, the bracket 2 may be permanently provided in the manhole cover receiving frame C in a fixed state.

In the figure, 11 is a fixing screw, and 12 is a supporting rod, which are connected to the bracket 2. 13 may be a seat, and 14 may be a contact piece for abutment, which may be substituted for the roller. In this case, it is easy to move in contact with the inner peripheral surface of the manhole. 30 post fitting interpolating the突杆, 31 are provided in order to facilitate locking the slide column 20 ₁ to the mobile when in Stay piece.

Note posts 20, 20 ₁ Yes using hollow tube and said hook
5,5 The ₁ are rotatably mounted to the cone support shaft 15, to easily move into the fitting easier and circumferentially into the grooves D of receiving frame C manhole cover is considered.

In the specific example of Figure 6 to Figure 8, which was a type that can desorb the bracket 2 to踏棧21 of the post 20 _1, the support piece is a pair to face one side of the bracket 2 1,1 A notch groove 10 that fits into the tread 21 is formed in the support piece 1, and a stopper 6 capable of engaging and disengaging the ladder A is provided on the support piece 1 by being biased in one direction by a spring 7.

In this case, as the stopper 6, wherein the support piece 1 be one obtained by pivoting the pivotally support piece 1 in the support shaft 8, integrally connected by a connecting rod ₆₁ for opposing provided a pair operation The claw is provided at a position for opening and closing the notch groove 10, is biased in the closing direction by the spring 7, and is formed on the stopper 6 when the stepping 21 of the ladder A is inserted into the notch groove 10. Part 9 is tread 21
In pushed Yes as the claw portion 9 was accommodated in the cut groove 10 open against the stopper 6 to the spring force of the spring 7 does not fall off close down the踏棧21, the connecting rod ₆₁ When removing When grasped and raised, the stopper 6 moves around the support shaft 8 and the claw portion 9
The ladder A can be removed from the open support piece 1.

[Advantages of the Invention] The present invention is provided with a support rail on a support column, a slide support column provided with a guide groove for sliding to be fitted to the support column, and a lock for engaging and disengaging a tread on the slide support column. the engaging piece 24 with the support shaft 26 to the strut 20 of the ladder a rotatably pivotally mounted, and a bracket 2 for mounting support having an arm 3 which can be attached to and detached from the manhole cover receiving frame C of the slide post 20 ₁ Since it is fixedly installed above, the ladder that can enter and exit the manhole can be easily fixed and set, and it can be used safely without wobbling or slipping during lifting and midway work, as well as in the manhole. It is easy to extend and retract, lightweight, easy to handle and handle, and can greatly expand the range of use of the ladder. In addition, it is easy to adjust the length and is easy to carry.

[Brief description of drawings]

The drawings show an embodiment of the present invention. Fig. 1 is a front view, Fig. 2 is a side view, Fig. 3 is a plan view, Fig. 4 is a perspective view of a state of use, and Fig. 5 is a partial cutaway thereof. Slope view, FIG. 6 is a sloping view in a folded state, FIG. 7 is a plan view of another embodiment of the mounting portion, and FIG.
The figure is its front view, and FIG. 9 is a side view. A ... Ladder, C ... Manhole cover receiving frame, D ... Groove, 1 ... Support piece, 2 ... Bracket, 3 ... Arm, 4 ... Pivot support, 5 ...
Hooks, 6 ... Stoppers, 7 ... Springs, 8 ... Support shafts, 9 ... Claws, 10 ... Notched grooves, 20 ... Posts, 20 ₁ ... Slide posts, 21 ...
Tread, 22 ... Rail, 23 ... Guide groove, 24 ... Locking piece, 25 ... Leg member, 26 ... Spindle, 27 ... Notch, 28 ... Stopper.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akira Umezu 1-1-6 Uchiyuki-cho, Chiyoda-ku, Tokyo Nihon Telegraph and Telephone Corporation (72) Kentaro Izawa 1-25-17 Himonya, Meguro-ku, Tokyo No. Tokyo Communication Engineering Co., Ltd. (72) Inventor Shojiro Yanagi 1-25-17 Himonya, Meguro-ku, Tokyo Tokyo Communication Engineering Co., Ltd.

Claims (5)

[Scope of utility model registration request] 1. A ladder (A) in which treads (21) are appropriately provided on both sides of a column (20), a supporting rail (22) is provided on one side of the column (20), and the rail (22) is provided. A slide column (20 ₁ ) provided with a slide guide groove (23) to be fitted to the slide column is slidably provided, and a lock column that can be engaged with and disengaged from a tread (21) on the slide column (20 ₁ ). For attachment and support, the stopper (24) is rotatably pivotally attached to the column (20) of the ladder (A) by the support shaft (26) and detachable from the manhole cover receiving frame (C). the bracket (2) the slide strut (20 ₁₎ ladders manhole, characterized in that fixed deployed above the a. 2. The fixed strut (20), wherein the strut (20) is a single strut and a leg member (25) is provided at a lower end portion thereof, and a slide strut is provided at an upper end portion of the fixed strut (20). (20 ₁₎ of the ladder rails (22) (22) utility model registration claims first upper claimed is obtained by deploying facing the supporting. 3. A utility model registration request, wherein the support column (20) is a slide column (20 ₁ ) slidably connected to which a flexible cord (29) is connected and disposed. Ladder according to claim 1 or 2. 4. A notch (27) for engaging the step (21) of the slide column (20) by the engaging piece (24) and a stopper (28) for opening and closing the notch (27). The ladder according to claim 2 or 3 which is provided with the utility model registration claim. 5. The bracket (2) is provided with the arm (3) pivotably supported by a pivotal support (4), and the bracket (2) and the arm (3) are provided with a manhole cover receiving frame (C). ) Hook (5) that can fit into the groove (D) formed in
(5 ₁ ) The scope of utility model registration claim 2
A ladder according to any one of items 4 to 4.