JP2001220975A - Tripodal stepladder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tripodal stepladder capable of easily adjusting an opening condition of a front leg and a support leg before work and preventing leg opening at work. SOLUTION: This tripodal stepladder A is provided with a front leg 1 for installing stepping sash bars 12 to 18 between frames 10, 11 and a support leg 2 for rotatably installing one end on an upper part of this front leg 1. A ratchet type wire restricting device 3 for journalling a ratchet wheel having a winding part in a housing is installed in a proper place of the support leg 2. The other end side 41 of a wire 4 having one end side 42 wound on the winding part is fixed to the stepping sash bar 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tripod-type stepladder which is often used in afforestation, civil engineering, landscaping, farms, and horticulture.

[0002]

2. Description of the Related Art Conventionally, for work in afforestation, civil engineering, landscaping, farms, and horticulture, a ladder-shaped front leg having a plurality of steps installed between left and right frames and an upper part of the front leg are conventionally used. A tripod-type stepladder having a supporting leg pivotally attached to the upper end is often used.

[0003] The tripod-type stepladder is easy to open due to its structure. If the legs are opened during the work, there is a possibility that the worker who is working on the stepladder loses his balance and falls. Therefore, conventionally, a structure (shown below) for preventing the legs from being opened during work has been used.

The other end of a rope whose one end is tied to a step is tied to a support leg (prior art 1). The ring on the other end of the chain, one end of which is fixed to the step, is hooked on a hook formed on the support leg (Utility Model Registration No. 3029041; Conventional Technique 2). A tip hook of a metal bar whose base end is pivotally attached to a support leg is fitted into a hole formed in a step (prior art 3).

[0005]

In the prior art 1, the rope is unraveled or forgotten to bind during the operation. Prior art 2
During the operation, the hanging chain may shake due to wind or the like, and the ring of the chain may come off from the hook of the support leg.
In the prior art 3, the degree of opening of the legs cannot be changed.
An object of the present invention is to provide a tripod-type stepladder which can easily adjust the degree of opening between a front leg and a supporting leg before work and prevents the leg from being opened during work.

[0006]

(1) A tripod-type stepladder is
In a tripod with a front leg with a plurality of steps crossed between the left and right frames and a support leg with one end rotatably attached to the upper part of the front leg, when the lock is released, the wire can be pulled out and in the opposite direction A wire restraining device capable of returning and locking the wire when locked was attached to an appropriate position of the support leg, and the other end of the wire was fixed to one of the steps of the front leg.

(2) The tripod-type stepladder is a tripod-type stepladder having a front leg in which a plurality of steps are provided between left and right frames, and a support leg having one end rotatably mounted on the front leg. A ratchet-type wire restraining device in which a ratchet wheel having a winding portion is pivotally mounted in a housing is attached to a proper position of the support leg, and one end of the wire that is wound by the winding portion is connected to one of the front legs. Fixed to the step.

(3) The tripod-type stepladder has the configuration described in (2) above, wherein the wire restraining device is located on the opposite side of the winding portion from the ratchet wheel having a goose tooth formed on the outer periphery. A spiral spring that fixes an outer end of the spring to an inner wall of the housing, fixes an inner end of the spring to a boss, and urges the ratchet wheel in a direction in which the wire is wound.
While being rotatably attached to the housing,
It has an operating portion extending outside the housing and a claw portion with which a claw meshes with the goose, and a restraint release lever in which the claw is biased in a goose direction by a spring.

[0009]

[Function and Effect of the Invention] [Claim 1] A tripod-type stepladder comprises a front leg having a plurality of steps provided between left and right frames, and a support leg having one end rotatably mounted on an upper portion of the front leg. Prepare. When the lock is released, the wire can be pulled out and returned in the opposite direction, and when the lock is applied, a wire restraining device that can restrain the wire is attached to the proper position of the support leg, and the other end of the wire is fixed to any of the front legs on the front leg. I have.

[0010] A tripod-type stepladder in which the wire is accommodated in the wire restraining device is carried to the work site, and the front legs are fixed to the ground of the work site. Unlock the wire restraint, spread the legs, and secure the legs to the ground at the work site.
If the lock is released and the support leg is widened, the degree of opening between the front leg and the support leg can be easily adjusted. Then, lock the legs after fixing them to the ground. In this state, the worker climbs on a stepladder and performs work (forestry, civil engineering, landscaping, farm, horticulture). At this time, since the wire is restrained by the wire restraining device, the spread of the front leg and the support leg can be prevented, and the fall of the worker can be prevented.

[Claim 2] A tripod-type stepladder includes a front leg having a plurality of steps crossed between left and right frames, and a support leg having one end rotatably mounted on an upper portion of the front leg. Then, a ratchet-type wire restraining device in which a ratchet wheel having a winding portion is pivotally mounted in the housing is attached to an appropriate position of the support leg, and one end of the wire is wound on the winding portion, and the other end of the wire is stepped on one of the front legs. It is fixed to the pier.

A tripod-type stepladder having a wire wound around a winding portion in the wire restraining device is carried to a work site, and the front legs are fixed to the ground at the work site. Release the wire restraint of the wire restraining device, spread the legs, and fix the legs on the ground at the work site. In addition, if the restraint is released and the support leg is widened, the degree of opening between the front leg and the support leg can be easily adjusted. Then, the wire restraint is returned after the support leg is fixed to the ground.
In this state, the worker climbs on a stepladder and performs work (forestry, civil engineering, landscaping, farm, horticulture). At this time, since the wire is restrained by the wire restraining device, the spread of the front leg and the support leg can be prevented, and the fall of the worker can be prevented.

[Claim 3] The wire restraining device is a ratchet wheel having a goose tooth formed on the outer periphery, a ratchet wheel located on the opposite side of the winding portion, the outer end of the spring is fixed to the inner wall of the housing, and the inner end of the spring is a boss. Part, and a spiral spring that urges the ratchet wheel in the direction of winding the wire, and a pawl that is rotatably attached to the housing, extends outside the housing, and engages with the goose teeth. And a release lever whose claw is biased in a goose direction by a spring. The tripod-type stepladder in which the wire is wound around the winding section in the wire restraining device is carried to the work site, and the front legs are fixed to the ground of the work site. Hold down the operation part of the restraint release lever to release the engagement between the ratchet wheel goose tooth and the restraint release lever claw.

In a state where the meshing is released, the support leg is spread by hand to set the front leg and the support leg at a predetermined angle, and the support leg is fixed to the ground at the work site. If the meshing is released and the support leg is widened, the degree of opening between the front leg and the support leg can be easily adjusted. Then, after the support leg is fixed to the ground, pressing of the operation unit is stopped, and the meshing state is restored. In this state, the worker climbs on a stepladder and performs work (forestry, civil engineering, landscaping, farm, horticulture).

[0015] During the operation, even if the front leg or the supporting leg is moved in the direction in which the front leg or the supporting leg spreads due to the movement of the worker, the ratchet wheel does not rotate because the goose of the ratchet wheel is engaged with the claw of the restraint release lever. At this time, since the wire is restrained, the spread of the front leg and the supporting leg can be prevented, and the fall of the worker can be prevented. When the operation is completed, the operation portion of the restraint release lever is pressed to release the engagement between the ratchet wheel goose tooth and the restraint release lever claw, the support leg is returned to the front leg direction, and the stepladder is withdrawn from the work site.

[0016]

Next, an embodiment of the present invention (corresponding to claims 1 to 3) will be described with reference to FIGS. The tripod-type stepladder A includes a front frame 10 and a rear frame 11.
The front leg 1 having the steps 12 to 18 interposed therebetween, the supporting leg 2 attached to the underframe 19 of the front leg 1, the wire restraining device 3 disposed on the supporting leg 2, and the wire restraining device 3
And the wire 4 having the other end 41 fixed to the step 15.

The steps 12 to 18 are rectangular hollow pipes to which treads are connected, and the steps 12, 13, 14, 15, 1
It is formed so that the size becomes smaller in the order of 6, 17, and 18. The front legs 1 (made of metal) are formed such that the step intervals 12 to 18 are welded at predetermined intervals between the front frames 10 and 10 and the rear frames 11 and 11 so that the frame intervals become narrower as going upward. ing.

The upper end of the rear frame 11 (made of a hollow pipe having a circular cross section) is bent in a substantially F-shape and connected to the upper end of the front frame 10. Front bar 19 at the top of each frame
1. The underframe 19 is formed by welding the rear horizontal bar 192. A disc-shaped flange plate 101 is attached to the lower ends of the front frames 10 and 10 (made of a hollow pipe having a circular cross section) to prevent sneaking into the ground and slipping.

The leg 2 (made of metal) is a hollow pipe having a circular cross section, and the upper end of the leg is rotatably attached to the rear horizontal bar 192. In addition, a disc-shaped flange plate 21 for preventing intrusion into the ground and slippage is also attached to the lower end of the support leg 2. The wire restraining device 3 includes a ratchet wheel 31 (see FIG. 4) and a spiral spring 32 (see FIG. 5).
And a release lever 33 (see FIG. 4) having an operating portion 331 and a claw portion 332, and is fixed to an appropriate position of the support leg 2 by a fixing band 34 (see FIGS. 1 to 3).

Ratchet wheel 31 (made of stainless steel)
Is a cylindrical winding portion 311 for winding the one end 42 of the wire 4, a disk-shaped central portion 312 having a goose tooth 310 formed on the outer circumference, and a disk-shaped winding portion 32 for accommodating the spiral spring 32. (See FIGS. 4 and 5).

The spiral spring 32 is located in the housing portion 313 on the opposite side of the winding portion 311, and fixes the spring outer end 321 to the inner wall of the housing 30 and fixes the spring inner end 322 to the boss 314 of the ratchet wheel 31. The ratchet wheel 31 is urged in the direction in which the wire 4 is wound.

The restraint release lever 33 (made of stainless steel)
A central portion is rotatably attached to the housing 30 and a plate-shaped operating portion 33 extending outside the housing 30.
1 and a claw portion 332 in which the claw 333 meshes with the goose tooth 310. One end of the restraint release lever 33 has a claw portion 332.
The hook 332 is urged toward the goose tooth 310 by a spring 334 having the other end hooked into the hole 301 to prevent the ratchet wheel 31 from returning.

The wire 4 (made of stainless steel) is taken out from the hole 302 of the housing 30, and the ring 411 on the other end 41 is fitted into an arc-shaped base 151 formed on the step 15.

Next, a method of using the tripod-type stepladder A will be briefly described. The wire 4 is wound by the winding unit 311 in the wire restraining device 3 and carries the stepladder A in the state of FIG. 3 to the work site.

The flange plates 101, 101 are fixed to the ground at the work site, and the operating portion 331 of the restraint release lever 33 is pressed down.
The engagement between the goose tooth 310 of the ratchet wheel 31 and the claw 333 of the restraint release lever 33 is released. With the operation part 331 held down, the leg 2 is spread by hand, and the front leg 1 and the leg 2 are set at a predetermined angle (see FIG. 2).

Release the hand from the operation unit 331, and fix the flange plate 21 of the support leg 2 to the ground at the work site (see FIG. 1). In this state, the worker puts his feet on the steps 12 to 18 and climbs on the stepladder A to perform work (forestry, civil engineering, landscaping, farm, horticulture).

During the operation, even if the front leg 1 and the supporting leg 2 are moved in the direction in which the front leg 1 and the supporting leg 2 are spread by the movement of the worker, the goose tooth 310 of the ratchet wheel 31 and the pawl 3
The ratchet wheel 31 does not rotate because 33 is engaged.

When the operation is completed, the operation portion 331 of the restraint release lever 33 is pressed to release the engagement between the goose tooth 310 of the ratchet wheel 31 and the claw 333 of the restraint release lever 33, and the support leg 2 is moved in the direction of the front leg 1. Return (see FIG. 3).

The tripod-type stepladder A of this embodiment has the following advantages. [A] The tripod-type stepladder A is carried to the work site, and the operation unit 331 is operated.
When you release your hand, the goose tooth 310 of the ratchet wheel 31
And the claw 333 of the restraint release lever 33 are engaged with each other, and the wire 4 is restrained by the wire restraining device 3. In this state, even if the worker puts his feet on the steps 12 to 18 and performs the work (forestation, civil engineering, landscaping, farm, gardening) by climbing the stepladder A, the front legs 1 and the supporting legs 2 do not spread, so Fall can be prevented.

The front leg 1 and the support leg 2 are opened by pressing the operation portion 331 and moving the support leg 2 in a state in which the engagement between the goose tooth 310 of the ratchet wheel 31 and the claw 333 of the restraint release lever 33 is released. The condition can be easily adjusted.

[A] The tripod-type stepladder A is suitable for use outdoors because the main parts of the wire 4 and the wire restraining device 3 are made of stainless steel, and this part is resistant to rust and has excellent durability.

[C] In the tripod-type stepladder A, the wire restraining device 3 for restraining the wire 4 is disposed on the lighter supporting leg 2, so that the worker can open and close the leg alone. be able to.

[D] In the tripod-type stepladder A, since the operating portion 331 of the wire restraining device 3 is formed on the lower side of the housing 30, even if a branch, fruit, or the like falls during the operation, the operating portion 33 is operated.
Hard to hit one.

The present invention includes the following embodiments in addition to the above embodiment. a. The tripod stepladder may have a pair of left and right frames (shown in FIG. 6). Further, a structure in which the operation unit 331 of the wire restraining device 3 is formed on the upper side of the housing 30 may be employed (shown in FIG. 6). Further, a top plate 190 may be used instead of the underframe 19. Further, a structure without the flange plate 101 may be employed.

B. The stepladder may be formed of aluminum, iron, stainless steel or the like. c. The base 151 and the wire restraining device 3 may be located at other positions as long as their heights are substantially the same.

[Brief description of the drawings]

FIG. 1 is a perspective view of a tripod stepladder according to one embodiment of the present invention.

FIG. 2 is an explanatory view showing a manner in which a tripod of a tripod is spread.

FIG. 3 is an explanatory view showing a state in which a tripod-type stepladder is closed.

FIG. 4 is a structural explanatory view of a wire restraining device.

FIG. 5 is a structural explanatory view of a wire restraining device.

FIG. 6 is a perspective view of a tripod stepladder according to another embodiment.

[Explanation of symbols]

 A tripod-type stepladder 1 front leg 2 support leg 3 wire restraining device 10 front frame (frame) 11 rear frame (frame) 13-18 stepping bar 30 housing 31 ratchet wheel 32 spiral spring 33 restraint release lever 41 other end 42 one end 310 Goose 311 Winding part 314 Boss part 321 Spring outer end 322 Spring inner end 331 Operating part 332 Claw part 333 Claw 334 Spring

Claims (3)

[Claims] 1. A tripod type stepladder having a front leg having a plurality of steps crossed between left and right frames and a support leg having one end rotatably mounted on an upper portion of the front leg. Pull out and return in the opposite direction,
A tripod-type stepladder, wherein a wire restraining device capable of restraining a wire when locked is attached to an appropriate position of the support leg, and the other end of the wire is fixed to any of the studs of the front leg. 2. A tripod-type stepladder having a front leg having a plurality of steps crossed between left and right frames and a support leg having one end rotatably mounted on an upper portion of the front leg, and a ratchet having a winding portion. A ratchet-type wire restraining device in which a wheel is axially mounted in a housing is attached to an appropriate position of the support leg, and one end of the wire is wound on the winding portion, and the other end of the wire is fixed to one of the front legs of the front leg. A tripod-type stepladder characterized by the following. 3. A wire restraining device comprising: a ratchet wheel having a goose tooth formed on an outer periphery thereof; a ratchet wheel located on a side opposite to the winding portion; an outer end of a spring fixed to an inner wall of the housing; And a spiral spring that urges the ratchet wheel in a direction in which the wire is wound, and is rotatably attached to the housing,
An operating portion extending outside the housing and a claw portion for engaging a claw with the goose, and a restraint release lever which is biased in a goose direction by a spring. The tripod stepladder according to 2.