WO2005122837A1

WO2005122837A1 - Foldable step stool

Info

Publication number: WO2005122837A1
Application number: PCT/CN2005/000849
Authority: WO
Inventors: Luhao Leng
Original assignee: Luhao Leng
Priority date: 2004-06-15
Filing date: 2005-06-15
Publication date: 2005-12-29
Also published as: CN2747972Y

Abstract

The present invent provides a foldable step stool, which comprising front legs, rear legs and a footboard, further comprising a pair of struts and a pair of inclined linkages, wherein the front ends of the struts are hinged to the front legs respectively, the rear ends of the struts are hinged to the rear legs respectively, the footboard is mounted on the struts, and the inclined linkages are hinged to the underside of the struts. The front legs, the rear legs, the struts and the inclined linkages constitute a hinged four connecting-rods mechanism, and with a limiting mechanism being provided on said four connecting-rods mechanism, the limiting mechanism is used to prevent the hinged four connecting-rods mechanism be folded as it being unfolded. The step stool may be folded or unfolded by the hinged four connecting-rods mechanism.

Description

TECHNICAL FIELD

The invention relates to a step ladder, in particular to a foldable step stool.

Background technique

The existing step stool generally includes two front legs, two rear legs, and a pedal; the upper ends of the two front legs are fixedly coupled with the upper ends of the two rear legs, respectively; and a pedal is fixed between the two front legs and the two rear legs. The applicant applied for a Chinese utility model patent with a patent number of 01261854.3 in 2001, which discloses an improvement of the ladder stool structure, which better solves the problem of the full folding of the ladder stool. The multiple step stools are completely closed for loading, which greatly reduces the carrying volume and reduces the transportation cost.

As shown in FIG. 11, the back leg 2 ′ of the step stool is directly connected to the front leg 1 ′ through a hinge 4 ′. In order to maintain stability during use, the top pedal (seat board) 3 ′ must be arranged between the front and rear legs. The side of the step stool is "A", so the size of the top pedal (seat board) 3 'is limited. If you need a larger pedal (seat board) 3', you must increase the top pedal (seat board) 3 'The distance from the hinge of the front and rear legs, or increase the distance between the bottom of the front and rear legs. Therefore, the use of this type of step ladder is restricted.

Summary of the invention

The purpose of the present invention is to overcome the above-mentioned shortcomings, and provide a foldable step stool that can increase the area of the top pedal (seat board) arbitrarily, and uses safety and reliability.

The present invention is designed based on such a concept. The front leg and rear leg connecting part of the prior art step stool and the top pedal (seat board) are combined into one, and a pair of support rods is added. The front end of the support rod and the front legs are combined. The rear end of the support rod is hinged to the back, and the top pedal is mounted on the support rod. The invention also includes a pair of stay rods, the stay rods are hinged to the lower portion of the support rod; the front leg, the rear leg, the stay rod and the support rod are connected and connected. A hinged four-link mechanism is formed; the hinged four-link mechanism is provided with a limit mechanism that can limit the hinged four-link mechanism to be folded in an open state.

The upper ends of the two front legs according to the present invention are fixedly connected to a front cross bar; the limit mechanism is arranged on the front cross bar, and the limit mechanism and the pedal cooperate to form a mechanism capable of preventing folding.

When the ladder stool is in an open state, the side front legs, rear legs and support rods are in an "h" shape.

When the step stool is opened, the included angle between the support rod and the front leg is greater than 90 °, and the included angle between the support rod and the rear leg is greater than 90 °.

This The limiting mechanism of the present invention has a hanging buckle fixed on the front crossbar, the hanging buckle has an elastic hook, and the elastic hook is provided with a barb.

The elastic hook according to the present invention is a hook of a plastic part or a hook of a sheet metal part bent into a barb. The top pedal is provided with a card hole, and the position of the card hole corresponds to the position of the limit mechanism provided on the front crossbar. The card hole is provided with a flange that cooperates with the barb. The flange assembly of the pedal assembly forms a mechanism to prevent folding.

One or several lower pedals are fixed between the two front legs; an auxiliary cross bar is fixed between the two rear legs.

The upper ends of the two rear legs extend upwards and backwards into two auxiliary frames, and an armrest is fixed between the upper ends of the two auxiliary frames.

It can be known from the foregoing description of the structure of the present invention that, compared with the background art, the present invention has the following advantages: First, the step stool of the present invention is unfolded or folded by a hinged four-link mechanism. When unfolded to a predetermined position, The limit mechanism restricts the folding of the hinged four-link mechanism, so that the hinged four-link mechanism is in a stable state. At this time, the ladder stool is in an unfolded state and is in an open working state;

Secondly, the ladder stool of the present invention has a limit mechanism provided on the front crossbar and a pedal assembly to form a mechanism capable of preventing folding. By limiting the rotation between the pedal assembly and the front leg assembly, a hinged four-link is defined. The mechanism of folding, opening or locking the limit mechanism is convenient, the locking limit is firm and reliable, and the user uses the ladder stool with high safety;

Third, when the step stool of the present invention is opened, the side front legs, rear legs, and support rods are "h" shaped, and the included angle between the support rods and the front legs is greater than 90 °. The included angle is greater than 90 °. The hinge of the articulated four-link mechanism is generally hinged by rivets. When the articulated four-link mechanism is subjected to downward pressure, the structure is stable, and only the tensile force is applied to each hinge, and the rivet gap is eliminated and it is not easy to loose; Therefore, when the area of the top pedal (seat board) is large, the stability of the step stool can still be maintained.

Fourthly, in the step stool of the present invention, the barb of the limit mechanism cooperates with the flange of the pedal assembly to form a mechanism to prevent folding, it is convenient to snore or lock the limit mechanism, and the lock limit is firm and reliable;

Fifth, in the step stool of the present invention, the elastic hook is a hook made of plastic or a hook bent into a sheet metal piece with barbs, which is convenient to manufacture and has low production costs;

Sixth, in the step stool of the present invention, the upper ends of the rear legs extend upward and backward into two auxiliary frames, and an armrest is fixed between the upper ends of the two auxiliary frames. The user is convenient to use, and has high safety when climbing up a step ladder. BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of a three-dimensional structure of a step stool of the present invention in an unfolded state;

FIG. 2 is a schematic diagram of the step stool of the present invention in an unfolded state;

FIG. 3 is a schematic right side view of the step stool of the present invention;

FIG. 4 is a schematic cross-sectional view taken along A-A of FIG. 3;

FIG. 5 is a schematic diagram of the three-dimensional structure of the step stool of the present invention in the folding process;

FIG. 6 is a schematic view of the three-dimensional structure of the step stool of the present invention in a folded state;

Figure 7 is a schematic perspective view of a front leg assembly of the present invention;

8 is a schematic perspective view of a hind leg assembly of the present invention;

FIG. 9 is a schematic exploded perspective view of the pedal assembly of the present invention;

Figure 10 is a schematic perspective view of a limiting mechanism of the present invention;

FIG. 11 is a schematic structural diagram of a prior art folding step stool.

detailed description

The present invention will be further described below with reference to the drawings 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10. A foldable step stool, as shown in FIGS. 1, 2, 3, 4, 5, and 6, includes a front leg assembly 1, a rear leg assembly 2, a diagonal rod assembly 3, and a pedal assembly 4. The front leg assembly 1, the rear leg assembly 2, the diagonal rod assembly 3, and the pedal assembly 4 are connected to form a hinged four-link mechanism. A limit mechanism 5 is provided on the hinged four-link mechanism to prevent the hinged four-link mechanism from being folded in the open state.

As shown in FIG. 7, the front leg assembly 1 includes two front legs 11, a front cross bar 12, and a lower pedal 13. The upper ends of the two front legs 11 extend rearwardly into a hook-shaped body 111. The left and right ends of the front crossbar 12 are fixedly coupled between the upper ends of the two front legs 11. The left and right sides of the lower pedal 13 are fixedly coupled between the middle portions of the two front legs 11.

As shown in FIG. 10, the position-limiting mechanism 5 includes a fixing sleeve 51 fixedly sleeved on the middle of the front crossbar 12, and a hanging buckle 52 extending upward from the upper surface of the fixing sleeve 51. The hanging buckle 52 is provided with an elastic hook 521, and the elastic hook 521 is provided with a barb 5211. The upper surface of the fixing sleeve 51 also extends upward into two auxiliary pieces 511. The hanging buckle 52 is located between the two auxiliary pieces 511, and the height of the hanging buckle 52 is higher than the height of the two auxiliary pieces 511. The limiting mechanism 5 is made of plastic parts.

As shown in FIG. 8, the rear leg assembly 2 includes two rear legs 21 and an auxiliary cross bar 22. The left and right ends of the auxiliary cross bar 22 are fixedly coupled between the middle portions of the two rear legs 21. The upper ends of the two rear legs 21 extend upward and rearward into two auxiliary frames 23, and an armrest 24 is fixed between the upper ends of the two auxiliary frames 23. The inclined rod assembly 3 includes two inclined rods 31.

As shown in FIG. 9, the pedal assembly 4 includes a pedal 41 and two support rods 42. The lower surface of the pedal 41 is recessed so that the sides of the pedal 41 form a frame. The two supporting rods 42 are L-shaped. The two support rods 42 are fixedly abutted to the left and right sides of the pedal 41, respectively. The rear end portions of the two support rods 42 protrude from the rear end portion of the pedal 41. The front part of the step board 41 abuts on the front crossbar 12. The pedal 41 is provided with a latching hole 411, and the position of the latching hole 411 corresponds to the position of the limit mechanism 5. The periphery of the card hole 411 extends downward into a positioning sleeve 4112. The inner side surface of the positioning sleeve 4112 is provided with a flange 4111 that cooperates with the barb 5211. The barb 5211 of the stopper mechanism 5 cooperates with the flange 4111 of the pedal assembly 4 to form a mechanism for preventing folding.

As shown in FIGS. 1, 2, 3, 4, 5, and 6, the upper ends of the two front legs 11 are riveted by rivets to be rotatably connected to the front ends of the two support rods 42 of the pedal assembly 4. The upper ends of the two rear legs 21 are rotatably connected to the rear ends of the two support rods 42 of the pedal assembly 4 through rivets, respectively. The front and rear ends of one stay rod 31 are rotatably coupled to the upper part of one front leg 11 and the middle and lower part of one rear leg 21 through rivets, and the front and rear ends of the other stay rod 31 are rotatably connected to the upper part of the other front leg 11 through rivets. And the middle and lower part of the other hind leg 21. When in the open state, the included angle between the pedal assembly 4 and the front leg assembly 1 is greater than 90 °, and the included angle between the pedal assembly 4 and the rear leg assembly 2 is greater than 90 °.

As shown in FIG. 4, when the ladder stool is opened, the front legs 11, the rear legs 21 and the support rods 42 on the side are "h" shaped.

The above are only the preferred embodiments of the present invention, so the scope of implementation of the present invention cannot be limited by this, that is, equivalent changes and modifications made according to the scope of the present invention rather than patents and the description should still belong to the present invention. Within the scope of the invention patent.

Industrial applicability

The foldable step stool of the invention has the advantages of simple structure, reliable use, large-scale industrial production, and good industrial applicability.

Claims

^ ^

1. A foldable step stool, comprising a front leg, a rear leg, and a pedal, characterized in that it further comprises a pair of support rods and a pair of diagonal stay rods, wherein the front end of the support rod is hinged to the front leg, and the rear end of the support rod is backward. The top pedal is hinged, and the top pedal is installed on the support rod; the stay rod is hinged on the lower part of the support rod; the front leg, the rear leg, the stay rod and the support rod form a hinged four-link mechanism; the hinged four-link mechanism is provided with a A limiting mechanism that restricts the hinged four-link mechanism from being folded in an open state.

2. The foldable step stool according to claim 1, characterized in that: the upper ends of the two front legs are fixedly connected to a front cross bar; a limit mechanism is arranged on the front cross bar, and the limit mechanism and the pedal cooperate to form A mechanism that prevents folding.

3. The foldable ladder stool according to claim 1, characterized in that, when the ladder stool is in an open state, the front legs, the rear legs and the supporting rods on the side are in an "h" shape.

4. The foldable step stool according to claim 2 or 3, characterized in that: when the step stool is opened, the included angle between the support rod and the front leg is greater than 90 °, and the clip formed by the support rod and the rear leg The angle is greater than 90 °.

5. The foldable step stool according to claim 2, characterized in that: the limit mechanism has a hanging buckle fixed on the front crossbar, the hanging buckle has an elastic hook, and the elastic hook is provided with Barb.

6. The foldable step stool according to claim 5, wherein the elastic hook is a hook of a plastic part or a hook of a sheet metal part bent into a barb.

7. The foldable ladder stool according to claim 1 or 5 or 6, characterized in that: the top pedal is provided with a card hole, and the position of the card hole corresponds to the position of the limit mechanism provided on the front crossbar. In position, the card hole is provided with a flange adapted to the barb, and the barb of the limiting mechanism and the flange of the pedal assembly cooperate to form a mechanism for preventing folding. .

8. The foldable step stool according to claim 2, characterized in that: one or several lower pedals are fixed between the two front legs; an auxiliary cross bar is fixed between the two rear legs.

9. The foldable ladder stool according to claim 1, characterized in that: the upper ends of the two rear legs extend upwards and backwards into two auxiliary frames, and an armrest is fixed between the upper ends of the two auxiliary frames.