JPH066699U - Telescopic ladder fixing device - Google Patents

Abstract

(57) [Summary] (Correction) [Purpose] To provide a fixing device for an expansion / contraction ladder that can lock and unlock the fixing device by one-touch operation. [Structure] Telescopic support columns 4 are slidably fitted to the parent support columns 1 arranged on the left and right of the ladder, the rack 4a is formed on the inner side surface of the telescopic support column, and the shoe guide case 7 is fixed on the inner side surface of the parent support column. Then, the rack shoe 8 is housed in the shoe guide case so that it can move back and forth in the direction of the rack on the inner side of the telescopic column, and the case guide groove 12 is vertically and longitudinally provided on the side surface of the shoe guide case and on the side wall of the rack shoe. Sliding grooves 13 each having a constant inclination are formed at positions substantially opposite to the case guide groove, and an operating rod 14 functioning as an operating surface is loosely fitted to both the case guide groove and the sliding groove as an inclined surface. Sir,
An operating mechanism is connected to the operating rod so that the rack shoe engages and disengages from the rack of the telescopic column via the sliding groove according to the operation of the operating rod that moves up and down along the case guide groove by the operating mechanism. Constitute.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a fixing device for an expansion / contraction ladder, which can lock and unlock the fixing device with one-touch operation.

[0002]

[Prior art]

 Conventionally, a ladder for climbing to a high place for work is, for example, one in which a large number of cross rails are attached between two long columns, and a ladder piece provided on the left and right is pivotally supported. A stepladder that is connected and placed on the ground in a substantially V shape is generally used. In addition, such a ladder is formed so that the lower ends of the columns can be expanded and contracted so that the ladder can be used even in places with poor scaffolding such as stairs or uneven ground.

Such an expandable structure of a ladder has, for example, an expandable support column slidably attached to a lower end portion of a parent support column, and further, a plurality of communication holes are provided in each parent support column at regular intervals. The expansion support is fixed to the parent support of the ladder via the pin and the length is adjusted.

However, when the length of the ladder is adjusted, the telescopic ladder having the fixing device as described above temporarily pulls out the pin fixing the parent strut and the telescopic strut from the communication hole, and then expands and contracts from the parent strut. It was very complicated because a series of operations were performed, such as extracting the pillars and adjusting the length, and then inserting the pins again into the matching communication holes.

Further, since the communication holes provided in the main support column are provided at regular intervals, the length of each support column of the ladder cannot be finely adjusted, and the ground remains in an unstable state. There was a risk that the ladder would fall over and an accident would occur when it was placed on the ground.

Therefore, in order to solve such a problem, the inventor of the present invention filed an application for an improved one-touch mountable expansion ladder fixing device in Japanese Patent Application No. 3-99593.

That is, as shown in FIG. 6, this improved fixing device is such that, as shown in FIG. 6, the expansion support 4 is slidably attached to each parent support 1 of the ladder in the vertical direction, and the side surface of the expansion support 4 is slidable. A rack 4a is formed on the main support column 1, and a rack shoe 8 that slides in the vertical direction is attached to the main support column 1 via a spring 21. By fitting the rack shoe 8 and the rack 4a, the main support column 1 is supported. By fixing the telescopic support 4 to 1 and further attaching the operation unit 20 for fitting / uncoupling with the rack 4a to the rack shoe 8, the conventional drawbacks have been solved.

[0008]

[Problems to be solved by the device]

 However, in such a one-touch operation fixing device, since the operating portion is arranged at the corner between the step of the ladder and the lower end of the parent post of the ladder, the operation of extending and retracting the ladder bends over to bend the parent post. It must be done at the lower end of the ladder, and it is difficult to extend and retract while checking the height of the ladder.

Therefore, it is necessary to repeat the operation of once completing the expansion / contraction operation with the waist bent and then standing up to check the height, and bending again to adjust if the height is not appropriate. Yes, it was complicated.

Further, since the operation portion projects at the corner between the step rail of the ladder and the lower end of the parent strut, there is a risk that the operation portion may hinder the user's work and stumble his / her feet.

An object of the present invention is to provide an expansion ladder fixing device that solves the above problems.

[0012]

[Means for Solving the Problems]

 In the present invention, telescopic support pillars are slidably fitted to the parent support pillars arranged on the left and right sides of the ladder, a rack is formed on the inner side surface of the expandable support pillar, and a shoe guide case is fixedly installed on the inner surface of the parent support pillar. The rack shoe is housed inside the shoe guide case so that it can move forward and backward in the rack direction on the inner side of the telescopic support, and the rack shoe is configured to be moved forward and backward by the operation mechanism installed at the required position of the main support. The forward / backward movement of the rack shoe is related to a fixing device for an expansion / contraction ladder configured to be performed through a sliding operation between an inclined surface provided on the rack shoe and an operating surface that abuts on the inclined surface.

Further, the present invention is, in the above-mentioned fixing device, further has a case guide groove formed in a vertical longitudinal direction on a side surface of the shoe guide case, and is fixed at a position substantially opposite to the case guide groove on a side wall of the rack shoe. An operating rod that forms an inclined sliding groove and functions as an operating surface is loosely fitted through the case guide groove and the sliding groove as an inclined surface, and the operating mechanism is linked to the operating groove. The present invention relates to a fixing device for a telescopic ladder configured such that the rack shoe is engaged with and disengaged from the rack of the telescopic column via the sliding hole according to the operation of the operating rod that is vertically moved along the case guide groove by the operating mechanism. It is a thing.

[0014]

【Example】

 Hereinafter, the present invention will be described in detail with reference to the embodiments shown in the accompanying drawings.

The present invention relates to a fixing device for an expansion / contraction ladder. As a basic structure of the expansion / contraction ladder, as shown in FIG. 1, parent struts 1 and 1 are arranged on the left and right at regular intervals. Then, a short step 2 is installed between the same parent columns 1 and 1 to form a ladder piece. The upper end of each of the two sets of ladder pieces is pivotally connected by a fitting 3 so that the legs can be freely opened.

As shown in FIG. 3, the parent struts 1 arranged on the left and right of the ladder are formed to have an approximately U-shaped cross section that opens toward the inside, and inside the parent stanchions 1, the parent struts 1 face outward. The telescopic support column 4 that has been opened is slidably fitted in the internal space of the parent support column 1 so that the opening directions face each other.

Further, as shown in FIG. 1, the telescopic support column 4 is slidable up and down, and the telescopic support column 4 is extracted from the parent support column 1 by a required length and fixed by a fixing device 6, and fixed. The stationary device 6 is operated by the operation mechanism 5 provided in the main support column 1. At the lower end of the telescopic column 4, a mounting table 4a for supporting the ladder A on the ground or the like is provided.

Then, by extending and contracting the telescopic struts 4, 4 from the front and rear parent struts 1, 1 and adjusting the length thereof, when the telescopic struts 4, 4 are placed on the stairs B, as shown in FIG. Stabilize ladder A. Further, since the length of each of the parent columns 1 can be adjusted, the parent column 1 can be stably placed on a scaffold of any shape such as uneven ground.

In the basic structure of the expandable ladder A described above, according to the present invention, as described below, the fixing device 6 is further provided inside the parent support 1, and the operating mechanism 5 for operating the fixing device 6 is provided. The feature is that it is provided at a required position of the column to facilitate the operation.

That is, as a main configuration of the fixing device 6, as shown in FIG. 3, from the shoe guide case 7 fixedly formed on the inner side surface of the parent support 1 and the rack shoe 8 housed in the internal space thereof. The shoe guide case 7 is formed of a tubular case having a substantially rectangular shape that opens in the direction of the telescopic support, and a substantially rectangular rack shoe 8 is provided in the internal space of the substantially rectangular case. It is stored so that it can move back and forth in the direction of the telescopic columns.

Reference numeral 9 is a female screw hole for attachment formed in an upper portion and a lower portion of the internal space of the shoe guide case 7, and 10 is a female screw hole 9 of the shoe guide case 7 penetrating the side wall of the parent support column 1. The fixing bolt screwed to the above is shown.

An engaging rack 11 is formed on the tip surface of the rack shoe 8, that is, the side surface on the side of the telescopic support. On both sides of the shoe guide case 7, a case guide groove 12 is provided with a constant width in the longitudinal direction, and further, a sliding groove 13 is formed on the rack shoe 8 at a position substantially opposite to the case guide groove 12. It is set up.

Moreover, a rod-shaped operating rod 14 is commonly inserted into the case guide groove 12 of the shoe guide case 7 and the sliding groove 13 of the rack shoe 8, and the operating rod 14 is used as the operating rod 14. When the rack shoe 8 is moved up and down along the case guide groove 12, the rack shoe 8 slides back and forth in the shoe guide case 7 in the direction of the telescopic column through the sliding groove 13 having a constant inclination.

A bracket 15 is connected to both ends of the operating rod 14, and the bracket 1
5, an operation lot 16 is continuously provided, and the other end of the operation lot 16 is bent at a right angle to form a hand operation portion 16a as shown in FIG. There is.

Therefore, the hand operation part 16a can be arranged at a position separated from the fixing device 6 portion including the shoe guide case 7 and the rack shoe 8. In addition, the middle of the operation lot 16 is held by guide brackets 17 which are continuously provided at several points on the inner side surface of the parent strut 1, and the guide bracket 17 and operating rod provided at the lowermost end. By interposing a spring 18 between the bracket 15 and the bracket 15, the operating rod 14 is constantly urged to be positioned at the lower ends of the groove 12 and the sliding groove 13 of the case guide. There is.

In the fixing device 6 of the expandable ladder A configured as described above, the inclination of the sliding groove 13 is such that the upper end of the sliding groove 13 is close to the engaging rack 11 and the lower end is away from the engaging rack 11. The inclination is as follows.

Therefore, from the state shown in FIG. 4, by pulling the hand operation portion 16a at the upper end of the operation lot 16 upward, the operating rod 14 can be slid upward against the bias of the spring 18. For example, the operating rod 14 slides from the lower end to the upper end while making contact with the case guide groove 12, and also slides from the lower end to the upper end while making contact with the sliding groove 13 of the rack shoe 8. Since the upper end of the sliding groove 13 is closer to the engaging rack 11 and the lower end thereof is inclined away from the engaging rack 11, the abutting action of the operating rod 14 and the sliding groove 13 causes the rack shoe 8 to expand and contract. The column 4 moves in a direction of retreating from the rack 4a, and the engagement between the engaging rack 11 and the rack 4a is released as shown in FIG. The fixed state of the fixing device 6 is released by the above operation.

On the other hand, if the bracket 15 and the operating rod 14 are moved downward as shown in FIG. 4 in accordance with the bias of the spring 18, the rack 4 a and the engaging rack 11 are separated from each other by the spring 18. It is brought into a fixed and engaged state by the urging force of the parent strut 1 as shown in FIG.
The telescopic columns 4 extracted with respect to are extracted and coupled and fixed at the position.

As described above, the telescopic ladder A fixed by the fixing device 6 can securely fix the parent strut 1 and the expansion strut 4 and the fixing position can be freely set. The operation mechanism 5 can easily fix and release the fixation.

Next, the operation of the telescopic ladder A provided with the fixing device 6 will be described in detail. When the ladder A is placed on the uneven shape or the stairs B as shown in FIG. Sliding the telescopic column 4 provided at the lower end of the first column 1 adjusts the length of each parent column 1 to stabilize the ladder A. Further, by urging the spring 18 of the fixing device 6, the rack shoe 8 in the shoe guide case 7 is fitted to the rack 4a of the telescopic column 4 and fixed, and the work on the ladder A is performed safely.

On the other hand, when performing the expansion / contraction operation of each parent strut 1, when the hand operation section 16a, which is a part of the operation mechanism 5 connected to the fixing device 6, is pulled upward, the engaging rack 11 and the rack 4a. The engaging support is released and the telescopic support 4 can be freely extracted from the main support 1, and when the hand operation part 16a is released at an appropriate position, the spring 18 biases the engaging rack 11 and the rack. 4a is engaged and fixed.

In the expansion and contraction operation as described above, since the hand operation portion 16a can be set at a position distant from the fixing device 6, it can be attached at a position where it can be easily operated, and the ladder A can be used. It is possible to perform expansion and contraction operations even while standing.

Further, since the fixing device 6 and the operating mechanism 5 are compactly housed in the parent support 1, the fixing device and the operating mechanism 5 are projected to the outside of the step rail 2 as in the conventional case. It is possible to eliminate the danger at work.

In the above-described embodiment, the forward / backward movement of the rack shoe 8 in the fixing device 6 forms the sliding groove 13 having a constant inclination on the side surface of the rack shoe 8, and the sliding groove 1
3 and the case guide groove 12 provided in the longitudinal direction on the side surface of the shoe guide case 7, the operating rod 14 is loosely fitted in common, and the operating mechanism 5 is interlocked continuously with the operating rod 14 to perform the same operation. Although the mechanism 5 is moved up and down along the case guide groove 12, the structure is not limited to this. The operation is such that the inclined surface provided on the rack shoe 8 and the inclined surface are in contact with each other. It suffices if it is configured to be performed through a sliding operation with the surface.

[0035]

[Effect of device]

 As described above, according to the present invention, when the ladder is placed on the stairs or uneven ground, the telescopic support provided at the lower end of each support of the ladder is slid to extend the length of each support. The rack shoe of the fixing device is fitted to the rack of the telescopic column to fix it, and the rack shoe of the parent column and the rack of the telescopic column are fixed by operating the operation lot of the operating mechanism. The fitting can be released and the telescopic column can be slid up and down with respect to the same parent column.

Further, according to the fixing device of the present invention, it is possible to extract each of the expansion and contraction columns and adjust the length while confirming the height of the ladder by itself, and the operability is dramatically improved.

Further, since the fixing device and the operating mechanism are housed inside the main pillar of the ladder, when the work is carried on the ladder like the conventional fixing device protruding from the step of the ladder. It did not get in the way of work and improved safety.

[Brief description of drawings]

FIG. 1 is an overall view of a telescopic ladder.

FIG. 2 is an explanatory diagram of the use of a telescopic ladder.

FIG. 3 is an exploded perspective view of an extension ladder fixing device according to the present invention.

FIG. 4 is an enlarged explanatory view of a main part of a fixing device of the telescopic ladder according to the present invention with a part cut away.

FIG. 5 is a cross-sectional view of a device for fixing an expandable ladder according to the present invention.

FIG. 6 is an explanatory view of a conventional expansion and contraction ladder fixing device.

[Explanation of symbols]

 1 Parent support 4 Telescopic support 4a Rack 5 Operating mechanism 7 Shoe guide case 8 Rack shoe 12 Case guide groove 13 Sliding groove 14 Operating rod

Claims (2)

[Scope of utility model registration request] 1. A telescopic strut (4) is slidably fitted into parent strut (1) arranged on the left and right of the ladder to form a rack (4a) on the inner surface of the telescopic strut (4), Secure the shoe guide case (7) on the inner surface of the column (1), and
The rack shoe (8) is housed inside the (7) so that it can be moved back and forth toward the rack (4a) on the inner side of the telescopic column (4), and the forward and backward movement of the rack shoe (8) is required by the parent column (1). The operation mechanism (5) is installed at the location, and the forward and backward movement of the rack shoe (8) is performed by sliding between the inclined surface provided on the rack shoe (8) and the operating surface abutting the inclined surface. Telescopic ladder configured to be performed via dynamic operation. 2. A telescopic strut (4) is slidably fitted into parent strut (1) arranged on the left and right of the ladder to form a rack (4a) on the inner side of the telescopic strut (4), Secure the shoe guide case (7) on the inner surface of the column (1), and
The rack shoe (8) is housed inside the telescopic support (4) so that it can move back and forth in the direction of the rack (4a), and the side of the shoe guide case (7) vertically guides the case. A groove (12) is formed, and a sliding groove (13) with a constant inclination is formed on the side wall of the rack shoe (8) at a position almost opposite to the case guide groove (12), and also functions as an operating surface. The operating rod (14) is loosely fitted to the case guide groove (12) and the sliding groove (13) as an inclined surface, and the operating mechanism (5) is linked to the operating rod (14). Then, the rack shoe (8) is extended through the sliding groove (13) according to the operation of the operating rod (14) that moves up and down along the case guide groove (12) by the operation mechanism (5).
A telescopic ladder configured to engage and disengage from the rack (4a) of (4).