JP2529326Y2 - Ladder structure - Google Patents

Description

[Detailed description of the invention] (A) Industrial application field The present invention relates to a ladder structure in which each of the pillars can be freely extended and retracted.

(B) Conventional technology Conventionally, a ladder for ascending to a high place to perform work or the like is, for example, one in which a number of horizontal rods are attached between two long columns, and provided on the left and right. A common stepladder is formed by pivotally connecting ladder pieces and placing the ladder pieces on the ground in a substantially C-shape.

In addition, such a ladder is formed so that the lower ends of the struts can be extended and contracted so that it can be used even on a place with poor scaffolding, such as steps or uneven ground.

The extension structure of such a ladder, for example,
The telescopic struts are slidably mounted, and each strut is provided with a plurality of communication holes at fixed intervals, and the ladder struts are fixed to the communication holes via pins to adjust the length. .

(C) Problems to be solved by the invention However, the ladder as described above has the following disadvantages.

That is, when adjusting the length of the ladder, once the pin fixing the column is removed from the communication hole, the length of each column and the telescopic column is adjusted, and the pin is inserted again into the corresponding communication hole. Because such operations are performed, such operations are
It was very complicated.

In addition, since the communication holes provided in the pillars are spaced at a fixed interval, the length of each pillar of the ladder can not be finely adjusted, and when placed on the ground etc. in an unstable state At the same time, the ladder could fall and cause an accident.

An object of the present invention is to provide a ladder structure that can solve the above-mentioned problems.

(D) Means for Solving the Problems In the present invention, a telescopic strut is vertically slidably attached to the lower end of each strut of a ladder, and a rack shoe attached to the strut is mounted on a rack surface formed on the telescopic strut. In a ladder structure configured to be adjustable in length by being engaged by the biasing force of a spring, the spring is mounted so as to expand and contract in the direction of expansion and contraction of the expansion column, and the rack shoe is expanded and contracted by the spring. That the rack surface can be engaged by being urged in a direction substantially perpendicular to the direction, and that the rack surface can be disengaged from the rack shoe by operating the operation lever provided on the rack shoe. A ladder structure is provided.

Further, an engaging pin is protruded from the rack shoe, and the engaging pin is fitted into and engaged with an oblong guide hole formed in an inclined shape so as to approach an upper surface of the rack upward. By the urging force of the spring that expands and contracts in the expansion and contraction direction, the rack shoe moves while being guided by the guide hole,
Another feature is that the rack shoe can be engaged with the rack surface.

In addition, the rack shoe is stored in the case attached to the column, and the rack shoe is formed with a sharp tapered surface facing upward, and a spring is attached to the tapered surface and the tapered surface formed in the case. Another feature is that the rack shoes can be engaged with the rack surface by being brought into sliding contact with the force.

Further, the operation lever is provided with a lock mechanism for preventing the rack shoe from moving downward.

(E) Function and effect In the present invention, the telescopic column attached to the lower end of each column of the ladder is slid up and down to adjust the extension length of the telescopic column from the column lower end, and the rack shoe is mounted on the rack surface. When the ladder is installed on stairs or uneven ground, etc. by fixing the strut and the telescopic strut by engaging
The ladder can be stably supported, the ladder can be prevented from tipping over, and safety when using the ladder can be increased.

In addition, since the spring for urging the rack shoe is mounted on the rack surface so as to expand and contract in the direction of expansion and contraction of the expansion column, the storage portion of the rack shoe does not protrude in a direction substantially perpendicular to the expansion and contraction direction of the expansion column. In addition, the size of the rack shoe storage portion can be reduced.

Furthermore, since the rack shoes are urged by the spring to be able to engage with the rack surface, the rack shoes are always urged in the direction of engaging with the rack surface, and the extension length of the telescopic strut from the lower end of the strut when the ladder is used. The ladder can be stably supported without changing easily, and the extension length of the telescopic strut from the lower end of the strut does not change when lifting and moving the ladder, making it easy to use Can be

Further, an engaging pin protruding from the rack shoe is fitted into and engaged with an elongated guide hole formed in an inclined shape so as to approach the rack surface upward, and the rack shoe is guided by the guide hole. Since the rack shoe is moved, the rack shoe can be smoothly moved along the guide hole by operating the operation lever provided on the rack shoe, and the operation lever releases the engagement between the rack shoe and the rack surface. Can be easily performed.

Further, by configuring the rack shoe to slide along the tapered surface of the case, the engagement between the rack shoe and the rack surface by the operation lever can be easily released.

Furthermore, by providing a lock mechanism on the operation lever to prevent the rack shoe from moving downward, it is possible to reliably prevent the extension length of the telescopic strut from the lower end of the strut from easily changing when using a ladder. In addition, the ladder can be stably supported, and even when the ladder is lifted and moved, the extension length of the telescopic strut from the lower end of the column does not change, and the usability can be improved.

(F) Embodiment The embodiment of the present invention will be described in detail with reference to the drawings. In the side view of FIG. 1, A indicates a ladder according to the present invention, and the ladder A is configured as follows.

That is, in the ladder A, the columns 1, 1 are arranged on the left and right at a fixed interval, and the short step 2 is laid between the columns 1, 1.

Further, in the present embodiment, a rotatable joint fitting 3 is attached to a middle portion of the pillars 1, 1 and the pillars 1, 1 are formed to be freely bent from the fittings 3, as shown in FIG. And ladder A
Is formed in a substantially C-shape, and a stepladder having stability with respect to the ground or the like is formed.

Reference numeral 4 denotes a stopper for opening the columns 1 and 1 provided on the fitting 3.

In addition, in such a ladder A, as shown in FIG.
Each of the columns 1, 1 is configured to be extendable and contractible, and the structure thereof will be described below in detail.

That is, in this embodiment, the column 1 is formed in a substantially C-shaped cross section, and the telescopic column 5 is nested in the column 1, and the telescopic column 5 is slid up and down.

Further, a mounting table 6 for supporting the ladder A on the ground or the like is provided at the lower end of the telescopic strut 5.

With this structure, the telescopic struts 5 of the struts 1 and 1 are extended and retracted, and the length of the telescoping struts 5 extending from the lower end of the strut 1 is adjusted so that the telescopic struts 5 are mounted on the stairs B as shown in FIG. When placed, the ladder A can be stabilized.

In the present invention, as shown in FIG.
The fixing device 7 for the telescopic strut 5 is attached to the fixing device 7. In this embodiment, the fixing device 7 is configured as follows.

That is, the fixing device 7 is provided with the uneven rack surface 8 formed on the side surface of the telescopic strut 5, and each strut 1,
The rack shoe 9 has an uneven shape and is mounted on the rack shoe 9.

Then, the rack shoe 9 of the column 1 is engaged with the rack surface 8 of the telescopic column 5 to fix the column 1 to the telescopic column 5.

Further, in this embodiment, as shown in FIGS. 2 and 3, the rack surface 8 is formed to be long in the vertical direction of the telescopic strut 5 and the rack shoe 9 is adjusted while adjusting the telescopic strut 5. Are engaged.

In this embodiment, as shown in FIG. 2, the case 10 of the fixing device 7 is attached to the groove 1a of the column 1 formed in a C-shape, and engages with the rack surface 8 of the telescopic column 5 in the case 10. The rack shoe 9 is slidably accommodated in a vertical direction.

The case 10 has a substantially triangular space S as shown in FIGS. 2 to 4, and has an opening at the front thereof, and the opening is communicated with the groove 1a of the column 1. Installed.

Reference numeral 10a denotes a mounting flange for the column 1 provided on the periphery of the opening of the case 10.

Further, a rack shoe 9 is housed in the space S of the case 10, and a front side of the rack shoe 9 is formed into a groove.
On the front side of a rack shoe 9 protruding inward from the column 1 from the column 1a and protruding in the direction of the column 1, an engaging rack 11 having an uneven shape for engaging with the rack surface 8 of the telescopic column 5 is formed.

In the present embodiment, a tapered surface 12 that is sharpened upward is formed on the rear surface of the case 10, and the tapered surface 12 is also formed on the rear surface of the rack shoe 9 stored in the space S of the case 10.
9a.

When the rack shoe 9 is slid upward by the tapered surface 12 of the case 10 and the tapered surface 9a of the rack shoe 9, the engaging rack 11 protrudes forward.
When the is slid downward, the engagement rack 11 is housed in the case 10.

In the present embodiment, a spring mounting hole 13a is provided on the lower surface of the rack shoe 9, a spring 13 is mounted in the mounting hole 13a, and the rack shoe 9 is biased by the spring 13 to move upward. The rack shoe 9 protrudes in the direction of the column 1 by the tapered surface 12 with the case 10.

With this structure, the rack shoe 9 can be engaged with the rack surface 8 of the telescopic strut 5 by the spring 13.

Further, in this embodiment, as shown in FIG. 2, an operation lever 14 which also functions as an engagement pin described later is protruded from the rack shoe 9 and the rack shoe 9 is operated by the operation lever 14.
Is released, and the length of extension of the telescopic strut 5 from the lower end of the strut 1 is adjusted.

That is, in the present embodiment, as shown in FIG. 2, an insertion hole 15 which is long in the left-right direction is provided on the side surface of the rack shoe 9 and the rack surface 8 is close to the left side surface of the case 10 facing upward. An inclined guide hole 16 is provided in a long hole shape.

Then, the operation lever 14 is inserted into the insertion hole 15 of the rack shoe 9 and the guide hole 16 of the case 10, and the operation lever
By pulling 14 downward, the rack shoe 9
10 and can be disengaged from the telescopic strut 5.

Further, as shown in FIGS. 2 and 3, the operation lever 14 is formed in a substantially U-shape in plan view, and the front portion 14a of the lever 14 is pivoted to the insertion hole 15 of the rack shoe 9. The lever 14 is freely inserted, and the rear portion 14b of the lever 14 is disposed below the case 10.

 Reference numeral 14-1 denotes a ring for mounting the operation lever 14.

As shown in FIG. 3, a recess 1 is provided below the case 10 so that the rear portion 14b of the operation lever 14 is locked.
7, the rear portion 14b of the operation lever 14 is locked by the concave portion 17, so that the rack shoe 9 does not move downward, that is, the engagement between the rack surface 8 and the rack shoe 9 is not released. doing.

3 and 4, a lock spring 20 is attached to the operation lever 14 and the case 10, and the operation lever 14 is always urged by the spring 20 to a state where the operation lever 14 is locked in the concave portion 17. I have.

Next, each of the columns 1, 1 of the ladder A is
The adjustment operation of 1 will be described in detail.

First, the operating lever 14 of the fixing device 7 is gripped by the rear portion 14b, and is rotated sideways around the front portion 14a to release the lever 14 from the concave portion 17 and release the lock.

By lowering the operation lever 14 along the guide hole 16 of the case 10, the rack shoe 9 in the case 10 is also lowered, and the shoe 9 is moved into the case by the tapered surface 12 of the case 10. And the engagement between the shoe 9 and the rack surface 8 of the telescopic strut 5 is released.

With the release of the telescopic strut 5, the telescopic strut 5 slides, and the length of the telescopic strut 5 projecting from the lower end of the strut 1 is adjusted.

Further, the rack shoe 9 easily projects by the bias of the spring 13 and engages with the rack surface 8 of the telescopic strut 5 to fix it.

Further, the operation lever 14 is fitted into the recess 17 by the lock spring 20 so that the fixing device 7 of the column 1 is not easily operated.

FIG. 5 shows another embodiment of the fixing device 7 and the case 10
A guide hole 21 is provided in the tapered surface 12 of the first embodiment, and the operation lever 14 is connected to the rack shoe 9 housed in the case 21 via the guide hole 21.

The operation lever 14 is provided on the tapered surface 9a of the rack shoe 9.
The rack shoe 9 is configured to slide vertically.

Then, the support 1 and the telescopic strut 5 are fixed by the fixing device 7, and the length of the telescopic strut 5 projecting from the lower end of the support 1 can be adjusted.

FIG. 6 shows another embodiment of the fixing device 7 for the telescopic strut 5, and the structure of the fixing device 7 will be described in detail.

That is, a case 30 having a substantially triangular shape in a side view is attached to the side surfaces of the left and right columns 1, 1 and the upper surface of the lowest step 2a, and a storage space 31 for the fixing device 7 is formed therein. I have.

The storage space 31 is connected to the side surfaces of the pillars 1 and 1 through communication holes 1b
It communicates with the inside of 2a.

The storage space 30 stores a triangular rack shoe 32 that engages with the rack surface 8 of the telescopic strut 5, and slides the rack shoe 32 along the inclined tapered surface 30a of the case 30. By moving the rack shoe 32, the rack shoe 32 is configured to be able to move forward and backward with respect to the column 1.

Further, on the side surface of the rack shoe 32, an engagement rack 32a is provided.
Is provided, and the telescopic support 5 is provided through the communication hole 1b on the side surface of the support 1.
On the rack surface 8.

In this embodiment, as shown in FIG. 8, a guide groove 33 is provided on the tapered surface 30a of the case 30 along the longitudinal direction, and the rack shoe 32 is provided as an operation lever through the groove 33.
The operation bolt 34 is connected.

An operation knob 35 is attached to the tip of the operation bolt 34, and the knob 35 is gripped and operated along the guide groove 33, so that the rack shoe 32 and the rack surface 8 of the telescopic support 5 are connected to each other. The engagement is released.

Reference numeral 36 denotes an auxiliary bolt for the rack shoe 32 provided in the guide groove 33.

Further, a spring 37 disposed in the step 2a through the communication hole 2b is provided below the rack shoe 32.
37 pushes the rack shoe 32 upward.

The taper surface 30a of the case 30 ensures that the rack shoe 32 and the rack surface 8 of the telescopic strut 5 are engaged.

Reference numeral 32b denotes a recess for mounting a spring 37 provided on the lower surface of the rack shoe 32.

In this embodiment, as shown in FIG. 8 and FIG. 9, a screwing portion 38 is provided on the operation bolt 34 and the operation knob 35, and the operation knob 35 is rotated to rotate the operation knob 35. Is configured to be able to advance and retreat.

Moreover, the guide groove 3 provided on the tapered surface 30a of the case 30
At the upper part of 3, there is provided an insertion hole 33a into which a projection 35a provided at the lower end of the knob 35 is inserted.

With such a configuration, as shown in FIG. 10, when adjusting the length of the columns 1 and 1, the operation knob 35 is rotated so that the protrusion 35a of the operation knob 35 is inserted through the fitting hole 33a of the guide groove 33. Remove, and operate the knob 35 along the guide groove 33 to release the engagement of the rack shoe 32.

On the other hand, when locking the fixing device 7, the operation knob 35
The operation knob 35 into the insertion hole 33a of the guide groove 33.
The knob 35 is fixed with the protrusion 35a interposed therebetween to prevent the rack shoe 32 from moving downward, thereby preventing the rack shoe 32 from being released.

As another embodiment, as shown in FIG. 11, an insertion hole 35b is provided in the operation knob 35, and the operation knob 35 is loosely fitted to the operation bolt 34 through the insertion hole 35b. A spring 39 is mounted on the tip of the operation bolt.

Then, the guide groove 33 is formed by the spring 39.
The protrusion 35a of the operation knob 35 is always fitted into the fitting hole 33a of the control knob 35.

As shown in FIG. 11, the operation of the above structure is performed by lifting the operation knob 35, disengaging the projection 35a of the knob 35 from the fitting hole 33a of the guide groove 33, and
To disengage the rack shoe 32,
The extension length of the telescopic strut 5 from the lower end of the strut 1 can be adjusted.

As described above, the embodiment of the present invention has the following effects.

In the present invention, when the ladder A is placed on the stairs B, the telescopic struts 5 provided at the lower ends of the struts 1, 1 of the ladder A are slid, so that the telescopic struts 5 from the lower end of the strut 1 are displaced. The ladder A can be stabilized by adjusting the overhang length.

In addition, the rack shoe 9 of each of the columns 1 and 1 is fixed by engaging the rack shoe 9 on the side surface of the telescopic column 5 by the bias of the spring 13, and furthermore, the column is moved by the operation lever 14. By disengaging the rack shoe 9 and the rack surface 8 of the telescopic strut 5 and sliding the telescopic strut 5 up and down with respect to the strut 1, the adjustment operation can be easily performed.

Further, the fixing of the support 1 and the telescopic support 5 is performed by the rack shoe 9.
And the rack surface 8 is engaged, so that the extension length of the telescopic strut 5 from the lower end of the strut 1 is finely adjusted,
The ladder A can be stabilized on the stairs B, and the ladder A can be prevented from falling. In the present invention, the extension column 5 attached to the lower end of each column 1 of the ladder A is slid up and down to adjust the extension length of the column 5 from the lower end of the column 1, and the rack shoe 8 is attached to the rack surface 8. 9 and the support 1 and the telescopic support 5
When the ladder A is installed on the stairs B or the uneven ground, the ladder A can be stably supported, and the ladder A can be prevented from falling down.
Safety during use can be improved.

In addition, since the spring 13 for urging the rack shoes 9 is attached to the rack surface 8 so as to extend and contract in the direction in which the telescopic struts 5 extend, the storage portion of the rack shoes 9 extends in a direction substantially perpendicular to the telescopic direction of the telescopic struts 5. The rack shoe 9 can be reduced in size without protruding.

Further, since the rack shoes 9 are urged by the springs 13 so as to be able to engage with the rack surface 8, the rack shoes 9 are always urged in the direction of engaging with the rack surface 8, so that when the ladder A is used, the extension shoes 5 The ladder A can be stably supported without easily changing the overhang length from the lower end of the support 1, and the overhang length of the telescopic support 5 from the lower end of the support 1 when the ladder A is lifted and moved. The usability can be improved without any change.

Further, an engaging pin projecting from the rack shoe 9 is fitted into and engaged with an elongated guide hole 16 formed in an inclined shape so as to approach the rack surface 8 upward. The rack shoe 9 can be moved smoothly along the guide hole 16 by operating the operation lever 14 provided on the rack shoe 9 because the rack shoe 9 is moved by being guided by the operation lever 14. The engagement between the rack shoe 9 and the rack surface 8 can be easily released.

Also, by configuring the rack shoe 9 to slide along the tapered surface 12 of the case 10, the operation lever
The disengagement of the rack shoe 9 from the rack surface 8 by the use of 14 can be easily performed.

Further, by providing the operating lever 14 with a lock mechanism for preventing the rack shoe 9 from moving downward, the extension length of the telescopic strut 5 from the lower end of the strut 1 easily changes when the ladder A is used. Can be reliably prevented, the ladder A can be stably supported, and even when the ladder A is lifted and moved, the extension length of the telescopic strut 5 from the lower end of the column 1 does not change, and the usability is good. Can be

[Brief description of the drawings]

FIG. 1 is an overall side view of a ladder according to the present invention, FIG. 2 is a perspective view showing a telescopic structure of the ladder, FIG. 3 is a side view of a fixing device,
4 is a plan view of the fixing device, FIG. 5 is an explanatory diagram of another embodiment of the fixing device, FIGS. 6 to 8 are explanatory diagrams of another embodiment of the fixing device, and FIG. FIG. 8 is a view taken along the line II of FIG. 8, FIG. 10 is an explanatory view showing an operation method of the fixing device, and FIG. In the figure, A: Ladder 1: Strut 5: Telescopic strut 8: Rack surface 9: Rack shoe 13: Spring 14: Operation lever

Claims (4)

(57) [Scope of request for utility model registration] A telescopic strut (5) is attached to the lower end of each strut (1) of a ladder (A) so as to be slidable up and down, and a strut is formed on a rack surface (8) formed on the telescopic strut (5). In a ladder structure having a length adjustable by engaging a rack shoe (9) attached to (1) with a biasing force of a spring (13), the spring (13) is provided with a telescopic strut (5). The rack shoe (9) is urged by the spring (13) in a direction substantially perpendicular to the direction in which the spring (13) extends and contracts, and can be engaged with the rack surface (8). A ladder structure wherein the engagement between the rack surface (8) and the rack shoe (9) can be released by operating an operation lever (14) provided on the rack shoe (9). . 2. An elongated guide hole (16) having an engaging pin protruding from said rack shoe (9), and said engaging pin being formed so as to be inclined upward and close to the rack surface. The rack shoe (9) is guided by the guide hole (16) and moved by the urging force of the spring (13) which is fitted and engaged with the telescopic strut (5) in the telescopic direction of the telescopic strut (5). The ladder structure according to claim 1, wherein the rack shoe (9) is engageable with the rack shoe (8). 3. A rack shoe is housed in a case (10) attached to a column (1), and a sharply tapered surface (9a) is formed on the rack shoe (9) upward. The rack shoe (9) can be engaged with the rack surface (8) by sliding the tapered surface (9a) and the tapered surface (12) formed in the case (10) by the urging force of the spring (13). The ladder structure according to claim 1, wherein: 4. A ladder according to claim 1, wherein said operating lever is provided with a lock mechanism for preventing the rack shoe from moving downward. Construction.