JPH11241498A - Expansion-contraction leg section of pedestal, etc. - Google Patents

Abstract

PROBLEM TO BE SOLVED: To bear the load of a pedestal, etc. firmly, and to carry out smooth expansion and contraction. SOLUTION: The notches of U-shaped or V-shaped doors, in which the lower sides are formed in notched fold-back sides, are formed to the side faces of an internal leg section 4. Sections surrounded by the notches are bent to the inside of the internal leg section 4 and formed in pin hanging sections 5 as reinforcing pieces 6. A plurality of the pin hanging sections 5 are separated and formed vertically at proper intervals. A pin 8, in which front ends can be projected to the internal leg section 4 side, is installed to an external leg section 3. A front end is urged in the direction of the internal leg section 4 by resilient force in the pin 8. Accordingly, the reinforcing pieces 6 reinforce sections among the upper and lower pin hanging sections 5, 5, and firmly bear load even when load works through the pins 8. The bent sections of the reinforcing pieces 6 are formed in curved surfaces, and the smooth extension of the internal leg section 4 is carried out while using the front end of the pin 8 as a guide.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to various instruments and machines such as worktables, display stands, stages and other pedestals, stepladders, ladders, etc. used in various fields such as construction and temporary construction sites, horticulture and the like. In particular, the present invention relates to a telescopic leg portion adopted to change the height.

[0002]

2. Description of the Related Art There has been developed a worktable, a display stand, a stepladder, a ladder, etc., whose height can be freely expanded and contracted according to the situation at the site and the purpose of use. In order to be able to expand and contract, there is an apparatus that employs expandable legs as shown in FIGS. As shown in the figure,
The legs are composed of outer outer legs a and inner legs b housed inside the outer legs a so as to be slidable, and the inner legs b slide freely with respect to the outer legs a. It moves so that the length of the entire leg expands and contracts.

In order to determine and fix the length of the extended inner leg b with respect to the outer leg a, a round or square pin hole c is formed on the outer peripheral surface of the inner leg b at appropriate intervals vertically. And a pin d protruding inward through the pin hole f is attached to the side surface of the outer leg portion a. This pin d is inserted or hooked into the desired pin hole c of the inner leg b to determine the length of the inner leg b that extends with respect to the outer leg a, and the overall length of the leg,
Pull to determine the height of the pedestal and the like.

[0004]

The problem with such a conventional telescopic leg is its strength. A plurality of pin holes c are punched out on the side surface of the inner leg b at intervals, and the distance e between the pin holes c is small. The weight of the pedestal and the like and the weight of the operator and the load placed thereon will be applied to the contact portion between the pin d and the pin hole c. This means that a very large weight acts on this small part, and the strength of that part is a very important issue. However, with such a configuration, only the extremely small portion remaining in the interval e between the pin holes c must receive this weight. If the length of expansion and contraction, that is, the height of the pedestal or the like can be adjusted more finely, the interval between the pin holes c and c becomes further narrower. The greater the weight remaining in the portion remaining in the smaller distance e, the greater the anxiety about its strength. If the pin d shifts due to a crack entering the space e between the pin holes c, c, the pedestal or the like may be greatly inclined or fall, leading to a large accident.

Another problem to be solved by the present invention is that
Smooth expansion and contraction of the legs. The inner leg b is extended and contracted with respect to the outer leg a to adjust the length of the leg. When the pin d projects toward the inner leg b by a spring force or the like, the pin d has a pin hole. The inner peripheral angle of c will be touched. When the pin hole c is punched, the corner of the inner peripheral portion of the pin hole c is angular over the entire circumference, so that the tip of the pin d is easily caught by the inner peripheral portion of the pin hole c, and the inner leg portion b is connected to the outer leg. When the pin d is extended with respect to the portion a, the pin d is caught in the pin hole c on the way and cannot be extended smoothly.

[0006]

According to the present invention, a telescopic leg such as a pedestal according to the present invention does not form a pin hooking portion formed on an inner leg by punching, but forms a U-shaped or U-shaped cut. And bend the part surrounded by the cut,
The above problem is solved by leaving a reinforcing piece between the pin hooking portions.

[0007]

According to the present invention, a cutout is formed in the side surface of the inner leg portion without using a punched pin hole, and a portion surrounded by the cutout is bent inward to form a reinforcing piece. It is a pin hook having a piece. The cut made in the inner leg portion is a cut in a U-shape or a U-shape in which the lower side is the folded side. When the lower side is turned back, the notch may be shaped so as to descend from one end of the cut to below the inner leg, turn back, and return the other end to above the inner leg, or may be a V-shaped cut. . The portion surrounded by the cut is bent toward the inside of the inner leg, that is, the side opposite to the side surface of the outer leg that is in contact. The bent portion may be bent as a reinforcing piece to an extent of forming substantially 90 degrees with the side surface of the inner leg. When bent, the reinforcing piece and the side surface of the inner leg portion form a gentle curved surface, and this curved surface is effective for smooth sliding of the pin described later.

A plurality of such pin hooks are formed on the side surface of the inner leg at appropriate intervals. The appropriate interval means that it is determined appropriately according to the stage required for adjusting the height of the pedestal or the like. A pin can be protruded from the outer leg portion outside the inner leg portion and in sliding contact with the inner leg portion toward the inner leg portion. In many cases, the inner leg portion is formed into a cylindrical shape, and the outer leg portion is formed into a cylindrical shape having a larger diameter or width than the inner leg portion so as to cover the outer side of the inner leg portion so that the inner leg portion can be pulled out from the outer leg portion. However, it is also conceivable that a hole is formed in the outer leg portion, a pin is inserted from the hole, and the pin is passed through the pin hook portion of the inner leg portion. In addition, a pin is attached to the outer leg in advance so that the tip of the pin can protrude from the hole formed in the outer leg, and the pin is urged to project inward from the hole by a spring force or the like. Things can also be adopted.

The inner leg is slid and extended with respect to the outer leg to determine the length of the leg according to the required height of the pedestal or the like. At this time, if the pin is urged toward the inner leg by the spring force or the like and projects toward the inner leg, the tip of the pin comes into contact with the side surface of the inner leg. In the case of conventional punched pin holes, the tip of the pin is caught at the corner of the inner periphery of the pin hole and it is impossible to stretch the inner leg smoothly, but a reinforcing piece is bent above the pin hook. The tip of the pin comes into contact with this curved surface and is guided to the side surface of the inner leg above the curved surface, and is automatically separated from the pin hooking portion, enabling smooth stretching. When the inner leg is stopped, the leg is automatically hooked appropriately to the pin hook, and the length of the leg is fixed. The weight of the pedestal or the like acts on the lower side of the pin hook portion via the pin. The lower side of the pin hook portion is a folded portion of the cut and is angular, so that the lock between the pin and the pin hook portion does not come off. The portion between the pin hooking portions is reinforced by the reinforcing piece thereunder, and has a strength that can withstand a large weight, so that there is no possibility of being damaged and leading to an accident.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on an embodiment shown in the drawings. In the figure, reference numeral 1 denotes a pedestal serving as a temporary work scaffold, and has four legs 2. The four legs 2 are extendable so that the height of the pedestal 1 can be adjusted. The leg 2 has an outer leg 3 and an inner leg 4 that is slightly thinner than the outer leg 3 so that it can be stored inside the outer leg 3. Both the outer leg 3 and the inner leg 4 have an oval cross section, and the inner leg 4 does not rotate with respect to the outer leg 3. In short, the inner leg 4 expands and contracts straight without rotating with respect to the outer leg 3.

A plurality of pin hooks 5 are formed on the side surface of the inner leg 4 at appropriate intervals above and below. The pin hook portion 5 has a U-shaped cut, and a portion inside the cut is bent toward the inside of the inner leg portion 4. The U-shaped bent portion is a reinforcing piece 6 which forms substantially 90 degrees with the side surface of the inner leg 4. That is, the reinforcing piece 6 is located above each pin hook portion,
It will be below the portion 7 between the upper and lower pin hooks 5,5.

A pin 8 is attached to the outer periphery of the outer leg 3. The pin 8 is made of a steel rod having a substantially Z-shape. The pin 8 is rotatably attached to a bracket 14 fixed to the outer periphery of the outer leg 3 at an intermediate portion. A pin hole 9 is formed in the side surface of the outer leg 3, and the lower end of the pin 8 can project from the pin hole 9 to the inside of the outer leg 3.
Urges the outer leg 3 inward.

Inside the upper end of the inner leg portion 4 is provided a detachment stopper 12 urged by a spring force toward a projection hole 11 formed on the outer periphery. The pin hole 9 of the outer leg 3
A stopper hole 13 is formed above the hole.

In order to increase the height of the pedestal 1, the inner leg 4 is pulled out from the outer leg 3. The tip of the pin 8 protrudes from the pin hole 9 of the outer leg portion 3 by a spring force, but the upper side of the pin hooking portion 5 is curved by bending the reinforcing piece 6 so that the tip of the pin 8 Even if it hits, it is automatically guided to the inner leg side. In this way, even if the pin 8 is not operated by the operator, the pin tip does not get caught in the middle and does not stop, so that smooth extension is possible. When the inner leg portion 4 is excessively extended from the outer leg portion 3 for some reason, the retaining piece 12 is caught by the retaining hole 13 of the outer leg portion 3 to prevent the inner leg portion 3 from coming off.

The load of the pedestal 1 or an operator thereon acts on the lower end of the pin hooking portion 5 via the pin 8, but the reinforcing piece 6 thereunder lowers the portion 7 between the pin hooking portions 6. It is reinforced and has the strength to support large loads. When the leg 2 is contracted, the upper end of the pin 8 is lifted up, the lower end of the pin 8 is retracted from the pin hole 9, and the inner leg 4 may be stored in the outer leg 3.

[0016]

The present invention has the above-described configuration, and can obtain the following effects. A U-shaped, U-shaped, or V-shaped notch whose lower side is the cut-back side is formed, and the inner part of this cut is bent into the inner leg to form a pin hole, so that it is bent. The portion which serves as a reinforcing piece reinforces the space between the pin hooking portions and strongly supports the load acting via the pins. Therefore, there is no possibility that the side surface of the inner leg is damaged and the pin is disengaged to cause a large accident. Since the strength between the pin hooking part and the pin hooking part is increased by the reinforcing pieces, the interval between the pin hooking parts can be made smaller, and the height of the pedestal etc. can be adjusted more finely, It will be possible to set the optimal height. Since the reinforcing piece is bent under the pin hook, the upper portion of the pin hook becomes a curved surface, and the tip of the pin is guided, so that the leg can be stretched smoothly. If the pin is biased so that the tip protrudes toward the inner leg, the curved surface under the pin hook allows for smooth expansion and contraction, and there is no need to operate the pin when the inner leg is stretched. Becomes

[Brief description of the drawings]

FIG. 1 is a perspective view of a pedestal.

FIG. 2 is a partial perspective view of an inner leg portion housed in an outer leg portion.

FIG. 3 is a sectional view of a leg.

FIG. 4 is a perspective view of a conventional telescopic leg.

FIG. 5 is a sectional view of a conventional telescopic leg.

[Description of Signs] 1 Pedestal 2 Leg 3 Outer leg 4 Inner leg 5 Pin hook 6 Reinforcement piece 7 Portion between pin hooks 8 Pin 9 Pin hole 10 Spring 11 Projection hole 12 Detachment stopper 13 Detachment stopper hole 14 Bracket

Claims (2)

[Claims] 1. A pin-hung portion having a U-shaped or U-shaped cut in which a lower side is a cut-back side and a portion surrounded by the cut is bent inward of an inner leg portion to form a reinforcing piece,
Expansion and contraction of a pedestal or the like that can be provided on the side of the inner leg that is housed in the outer leg and slides at appropriate intervals in the up and down direction, so that pins can protrude from the desired location of the outer leg toward the inner leg. leg. 2. The pin is attached to the outer leg by biasing the tip so as to protrude toward the inner leg.
Telescopic legs such as the pedestal described.