CN102900352A - Foldable ladder - Google Patents

Abstract

The invention provides a foldable ladder. The foldable ladder comprises a first piece of ladder and a second piece of ladder which are hinged with each other, wherein the first piece of ladder comprises a first vertical edge of the first piece of ladder, a second vertical edge of the first piece of ladder and a horizontal ladder; the first vertical edge of the first piece of ladder and the second vertical edge of the first piece of ladder are respectively located at two side edges and are connected by the horizontal ladder; the second piece of ladder comprises the first vertical edge of the second piece of ladder, the second vertical edge of the second piece of ladder and the horizontal ladder; the first vertical edge of the second piece of ladder and the second vertical edge of the second piece of ladder are respectively located at the two side edges and are connected by the horizontal ladder; a first supporting point for supporting an operating surface is arranged at the lower end of the first vertical edge of the first piece of ladder; a second supporting point for supporting the operating surface is arranged at the second vertical edge of the first piece of ladder; a third supporting point for supporting the operating surface is arranged at the first vertical edge of the second piece of ladder; a fourth supporting point for supporting the operating surface is arranged at the second vertical edge of the second piece of ladder; the first supporting point and the third supporting point are located on the same side of the foldable ladder; and the second supporting point and the fourth supporting point are located on the other side of the foldable ladder.

Description

folding ladder

technical field

The invention relates to a foldable ladder, that is, the invention relates to a foldable ladder.

Background technique

Ladder is a tool commonly used in people's life and work. At present, the commonly used folding ladders on the market are divided into two hinged ladders. When in use, the two hinged ladders are opened, and the whole folding ladder is supported on the ground in a herringbone shape. People can stand on the ladder or the pedals on the ladder. When working, the two ladders can be combined together when not working, so this kind of ladder is also called a herringbone ladder. Although the folding ladder is supported on the ground in a herringbone shape, which can prevent the folding ladder from toppling forward and backward in the herringbone plane, the folding ladder is supported on the ground by four points or two parallel lines, and the folding ladder is easy to move vertically to the herringbone plane. Direction topples, that is, topples outward along the direction parallel to the hinge axis, which brings great potential safety hazards to human operations.

Contents of the invention

The object of the present invention is to provide a folding ladder that can prevent falling in the direction perpendicular to the herringbone plane, so as to solve the problem of unstable support of the existing folding ladder.

For this reason, the present invention proposes a folding ladder, which includes: a first ladder and a second ladder hinged by a hinge shaft,

The first ladder comprises: the first vertical side 11 of the first ladder located at the edges of both sides, the second vertical side 12 of the first ladder and the second vertical side connected between the first vertical side 11 and the first ladder. The horizontal ladder between the sides 12, the second ladder includes: the first vertical edge 21 of the second ladder at the edge of both sides, the second vertical edge 22 of the second ladder and the first vertical edge 21 and the second vertical edge 22 of the second ladder. The horizontal ladder between the second vertical sides 22 of the second ladder, the lower end of the first vertical side 11 of the first ladder has a first fulcrum supported on the working surface, and the first fulcrum of the first ladder is The two vertical sides 12 have a second fulcrum supported on the working surface, the first vertical side 21 of the second ladder has a third fulcrum supported on the working surface, the second vertical side 22 of the second ladder There is a fourth fulcrum supported on the working surface, the first fulcrum and the third fulcrum are located on one side of the folding ladder, and the second fulcrum and the fourth fulcrum are located on the other side of the folding ladder,

The folding ladder also includes: two supporting legs hinged on the hinge shaft of the hinge, the supporting legs are a first supporting leg and a second supporting leg respectively, and the first supporting leg is located on the first The outside of the plane formed by the first vertical side 11 of the ladder and the first vertical side 21 of the second ladder, the second support leg is located at the second vertical side 12 of the first ladder and the second vertical side of the second ladder. The outer side of the plane formed by the vertical edge 22.

Further, the first support leg has a first support portion supported on the working surface, the second support leg has a second support portion supported on the work surface, the first support portion, the first The fulcrum and the third fulcrum form a first polygonal support plane, the second support part, the second fulcrum and the fourth fulcrum form a second polygonal support plane, and the first polygonal support plane and the first polygonal support plane Two polygonal support planes are set symmetrically.

Further, both the first support leg and the second support leg are support rods, the first support part and the second support part are support points, and the first polygonal support plane and the second polygonal support plane The support planes are all isosceles triangles, the distance between the first support part and the first fulcrum is equal to the distance between the first support part and the third fulcrum, and the distance between the second support part and the second fulcrum The distance is equal to the distance between the second support part and the fourth fulcrum.

Further, the supporting legs are hinged on the hinge shaft of the hinge through a hinge structure,

The hinged structure includes: a rotatable supporting leg sleeve sleeved on the hinge shaft and a supporting leg connecting shaft radially passing through the supporting leg sleeve, the axis of the supporting leg connecting shaft is vertical The axis of the supporting leg bushing, the supporting leg is hinged on the supporting leg bushing through the supporting leg connecting shaft, the supporting leg is hinged on the hinge hinge shaft through the supporting leg bushing, or, the The hinge structure includes: a rotatable supporting leg connecting shaft which is passed through the hinge shaft, and the axis of the supporting leg connecting shaft is perpendicular to the hinge shaft.

Further, the end of the hinge shaft is provided with a limiting boss, and one end of the sleeve is provided with an assembly hole, and the sleeve is sleeved on the hinge shaft through the assembly hole, and the The radial dimension of the limiting boss is larger than the aperture of the assembly hole, so as to prevent the sleeve from sliding out from the end of the hinge shaft, and the other end of the sleeve is provided with an open slot, and the connecting shaft of the support leg passes through vertically. Through the opening of the opening slot, the top end of the supporting leg is provided with a connecting portion hinged to the connecting shaft of the supporting leg, and the connecting portion is rotatably arranged in the opening slot.

Further, the folding ladder also includes:

A step that can be folded is connected between the first ladder and the second ladder, and the step includes: a first step and a second step hinged by a step hinge,

The pedal hinge includes: a first chain link, a pedal hinge shaft and a second chain link, the first chain link and the second chain link are hinged through the pedal hinge shaft, and the first chain link includes: a first pressing contact part and the side lug connected with the first pressing contact part, the side lug is provided with a first shaft hole, and the second chain link includes: a second pressing contact part and a the second shaft hole on the upper portion, the pedal hinge passes through the first shaft hole and the second shaft hole;

The first pedal is connected to the top of the first pressing contact part, and the second pedal is connected to the top of the first pressing contact part;

The first pressing contact part and the second pressing contact part are pressed against each other on the contact point, and the first pressing contact part includes: a first pressing contact line, and the second pressing contact part It includes: a second extruded contact line, the first extruded contact line and the second extruded contact line face each other and press against the normal line of the contact point, and the side ears are formed from the first extruded contact line. The contact part protrudes laterally and passes through the normal line of the contact point and extends toward the direction of the second pressing contact part, and the first shaft hole is aligned with the second shaft hole and the pedal hinge, and the The first extruded contact line includes: the first contact a1 at the upper end and the first contact b1 at the lower end, and the second extruded contact line includes: the second contact a2 at the upper end and the second contact b2 at the lower end, The distance d1 between the first contact at the upper end and the first shaft hole is smaller than the distance d2 between the first contact at the lower end and the first shaft hole, and the second contact at the upper end The distance d3 between the second shaft hole and the second shaft hole is greater than the distance d4 between the second contact point at the lower end and the second shaft hole.

When the pedal is opened and in a no-load state, the first contact a1 at the upper end is pressed against the second contact a2 at the upper end, and the first extrusion contact line and the second extrusion contact line are in point contact pressed together;

When the pedal is opened and under load, the first contact a1 at the upper end is pressed against the second contact a2 at the upper end, and the first contact b1 at the lower end is pressed against the second contact b2 at the lower end , the first extruded contact wire and the second extruded contact wire are pressed together by line contact.

Further, from the upper end to the lower end, the distance between each point on the first extrusion contact line and the first shaft hole gradually increases, and the first extrusion contact line and the second extrusion contact line The shape is the same, the first extrusion contact line and the second extrusion contact line are arranged symmetrically, the first extrusion contact part has a first horizontal surface (519) passing through the first contact a1, and the first pedal is arranged on On the first horizontal surface, the second pressing contact part has a second horizontal surface (539) passing through the second contact a2, the second pedal is arranged on the second horizontal surface, and the first contact a1 The distance from the first horizontal surface (519) is greater than the distance between the first shaft hole (513) and the horizontal surface (519), and the distance between the second contact a2 and the second horizontal surface (539) is greater than the distance between the first shaft hole (513) and the horizontal surface (519). The distance between the second shaft hole (533) and the second horizontal surface (539).

Further, the first extrusion contact line is a straight line or a smooth curve, and the distance d1 between the first contact at the upper end and the first shaft hole is smaller than the distance d1 between the first contact at the lower end and the first shaft hole. The value of the distance d2 between them is 0.05 to 0.30 mm. In addition, the two support legs, the first ladder and the second ladder are all telescopic.

Further, the folding ladder further includes: a connecting rod 6 connected between the first ladder, the second ladder, the first supporting leg and the second supporting leg, and the connecting rod is located on the pedal Below, the connecting rod includes:

The middle rod 60 is parallel to the hinge axis of the hinge and located under the hinge shaft, and the middle rod 60 is arranged in the middle position between the first ladder and the second ladder;

a first section bar 611 hinged between said middle bar and the first vertical edge 11 of the first ladder;

a second section bar 612 hinged between said middle bar and the second vertical edge 12 of the first ladder;

a third section bar 621 hinged between said middle bar and the first vertical side 21 of the second ladder;

a fourth section bar 622 hinged between said middle bar and the second vertical edge 22 of the second ladder;

a fifth section rod 641 hinged between the first end of the middle rod and the first support leg 41;

The sixth section rod 642 is hinged between the second end of the middle rod and the second supporting leg 42 .

Further, the first section bar 611, the third section bar 621, the first vertical side 11 of the first piece of ladder and the first vertical side 21 of the second piece of ladder are coplanar and are all perpendicular to the The middle bar 60; the second section bar 612, the fourth section bar 622, the second vertical side 12 of the first ladder and the second vertical side 22 of the second ladder are coplanar and uniform Vertically the middle pole.

The beneficial effects of the present invention have:

The folding ladder of the present invention has supporting legs hinged on the hinge shaft of the hinge. After the folding ladder is opened, the two supporting legs are respectively supported on both sides of the folding ladder, which can prevent the ladder from toppling to any side and ensure the safety of personnel. Operational safety. In addition, the supporting legs are supported on the hinge shaft of the ladder, and the supporting position reaches the highest supportable position of the ladder. From the perspective of the overall mechanics of the ladder, the support of the whole ladder is the most stable, and it is not easy to fall sideways.

Furthermore, the supporting legs of the present invention are connected to the two ladders through the hinges opened in multiple directions, and each supporting leg can freely rotate within the hemisphere range on each side, and can be rotated around the hinge axis according to the first ladder and the first ladder. The opening direction rotation of the second ladder can also be rotated perpendicular to the opening direction of the first ladder and the second ladder, and can also be rotated at various arbitrary angles up, down, front, back, left, and right, so that in the process of unfolding or retracting the supporting legs , Through rotation in different directions and angles, it can avoid complex on-site working environments, bypass various obstacles in narrow spaces or obstacles in different positions, and realize quick and convenient deployment or storage.

Furthermore, the present invention adopts the method of setting a support rod on each side, so that the lateral support plane is triangular, which increases the stability of the ladder to the greatest extent.

Furthermore, the present invention provides the support force in the vertical direction for the pedal through the extruded pedal hinge, which utilizes the good deformation characteristics of the metal. Bracket or added hinge), this structure is simpler, reduces the setting of other supports, reduces the processing and manufacturing time, and saves space and cost. Since the process of opening and folding is realized only by applying force, there is no need to operate additional components, thereby simplifying the steps when the pedal is opened and folded.

Furthermore, the present invention connects the supporting legs and each piece of ladder through the pull rod, which increases the stability of each piece of ladder when it is opened, increases the stability of each supporting leg when it is opened, and also increases the connection strength between the supporting leg and each piece of ladder.

Description of drawings

FIG. 1 is a schematic diagram of a three-dimensional structure of a folding ladder according to an embodiment of the present invention;

Fig. 2 schematically shows the three-dimensional structure of the hinge shaft and the connecting shaft of the supporting leg according to an embodiment of the present invention;

Fig. 3 schematically shows the cross-sectional structure of the hinge shaft and the connecting shaft of the supporting leg according to an embodiment of the present invention;

Fig. 4 schematically shows the three-dimensional structure of the pedal according to an embodiment of the present invention;

Fig. 5 schematically shows an exploded structure of a pedal hinge according to an embodiment of the present invention in a perspective view;

Fig. 6 schematically shows an exploded structure of a pedal hinge according to an embodiment of the present invention in a front view;

Fig. 7 schematically shows the matching structure of the pedal hinge according to the embodiment of the present invention in a cross-sectional view, wherein the first chain link and the second chain link are pressed against each other;

Fig. 8 schematically shows the structure of a first chain link according to an embodiment of the present invention in a front view;

Fig. 9 schematically shows the structure of a second chain link according to an embodiment of the present invention in a front view;

Fig. 10 schematically shows the structure of the first chain link and the second chain link in a no-load state according to the embodiment of the present invention in a cross-sectional view, wherein the first contact a1 and the second contact a2 are both connected to The normal EE has a significant distance;

Fig. 11 schematically shows the structure of the first chain link and the second chain link in a no-load state according to an embodiment of the present invention in a cross-sectional view, wherein the first contact a1 and the second contact a2 are nearly coincident ;

Fig. 12 schematically shows the structure of the first chain link and the second chain link when they are pressed against each other under a load state according to an embodiment of the present invention in a cross-sectional view;

Fig. 13 schematically shows a three-dimensional structure of a pull rod according to an embodiment of the present invention;

Fig. 14 schematically shows a cross-sectional structure of a hinge shaft and a connecting shaft of a supporting leg according to another embodiment of the present invention. Explanation of reference numbers:

Detailed ways

In order to have a clearer understanding of the technical features, purposes and effects of the present invention, the specific implementation manners of the present invention will now be described with reference to the accompanying drawings.

As shown in FIG. 1 , the folding ladder according to the embodiment of the present invention includes: a first piece of ladder 1 and a second piece of ladder 2 hinged by a hinge shaft 30 .

The first piece of ladder 1 comprises: the first vertical side 11 of the first piece of ladder respectively positioned at the edge of both sides, the second vertical side 12 of the first piece of ladder and the second vertical side 11 connected to the first piece of ladder The horizontal ladder between the vertical sides 12, the second ladder 2 includes: the first vertical side 21 of the second ladder at the edge of both sides, the second vertical side 22 of the second ladder and the first vertical side connected to the first vertical side 21 and the second vertical side 22 of the second ladder, the lower end of the first vertical side 11 of the first ladder has a first fulcrum 110 supported on the working surface, the first The second vertical side 12 of the ladder has a second fulcrum 120 supported on the working surface, and the first vertical side 21 of the second ladder has a third fulcrum 210 supported on the working surface. The second vertical side 22 has a fourth fulcrum 220 supported on a working surface, which is the ground or a supporting surface of an indoor or outdoor workplace. The first fulcrum 110 and the third fulcrum 210 are located on one side of the folding ladder, and the second fulcrum 120 and the fourth fulcrum 220 are located on the other side of the folding ladder.

The folding ladder also includes: supporting legs hinged on the hinge shaft 30, the supporting legs are two, respectively a first supporting leg 41 and a second supporting leg 42, the first supporting leg 41 Located on the outside of the plane formed by the first vertical edge 11 of the first ladder and the first vertical edge 21 of the second ladder, the second support leg 42 is located between the second vertical edge 12 and the second vertical edge of the first ladder. The outside of the plane formed by the second vertical edge 22 of the sheet ladder. After the folding ladder is opened, the two supporting legs are respectively supported on both sides of the folding ladder, which can prevent the ladder from toppling to any side and ensure the safety of personnel operation.

The length of the supporting legs can be equal to the length of each vertical side of each ladder, and can also be greater than the length of each vertical side of each ladder to obtain a wider support range. When being folded, the supporting legs can be close together with the adjacent vertical sides. In addition, for the stowed ladder, the ladder can be placed vertically on the ground. In addition to the two fulcrums on each side, the support points of the supporting legs are also added, which also forms a small triangle, which can make the ladders close together when they are close together. It can be supported relatively stably on the working surface, and can obtain a more stable support effect than ordinary ladders.

When the supporting legs are stably supported, the plane where the supporting legs and the hinge shaft 30 are located is located on a vertical plane passing through the hinge shaft 30 . The angles at which the supporting legs are deployed can vary, and the angles at which the supporting legs are deployed can vary with the variation of the angles at which the two ladders are deployed. The support legs, first ladder and second ladder may also be retractable for portability and wider support angles. For example, the two supporting legs, the first piece of ladder and the second piece of ladder are all retractable, so that the ladder can be supported on uneven terrain, such as supporting in field engineering, electric power construction, and can be erected in water or in mountains Superior and complex terrain, especially the two support legs are retractable, which further liberates the limitations of the support of the first ladder and the second ladder, and can adapt to various complex terrains.

Further, as shown in Figure 1, the first support leg has a first support portion 410 supported on the work surface, the second support leg has a second support portion 420 supported on the work surface, the first support part 410, the first fulcrum 110 and the third fulcrum 220 form a first polygonal support plane, and the second support part 120, the second fulcrum 210 and the fourth fulcrum 220 form a second polygonal support plane , the first polygonal support plane and the second polygonal support plane are arranged symmetrically. Before there is no supporting leg support, on the side of the ladder, only the first fulcrum 110 and the third fulcrum 220 form a line support, and the second fulcrum 210 and the fourth fulcrum 220 form a line support, which is difficult to provide stable support. Through the support legs and the above-mentioned fulcrums, the surface support on the side of the ladder can be formed, which can be a triangular support plane, a quadrilateral support plane, a pentagonal support plane or even a polygon with more sides. All these polygons can form a stable support. For example, the first support leg 41 and the second support leg 42 are openable herringbone brackets. At this time, the support plane is a trapezoid. When folded, the two hinged herringbone brackets and the first ladder and the first ladder are brought together in a plane, and when opened, the two hinged struts are respectively located on both sides of the vertical plane passing through the hinge shaft.

Preferably, the first support leg 41 and the second support leg 42 are support rods, the first support portion and the second support portion are support points, and the first polygonal support plane and the second support The polygonal supporting planes are all isosceles triangles, and the supporting parts are located at the vertices of the isosceles triangles. Both the first supporting leg 41 and the second supporting leg 42 are located in a vertical plane passing through the hinge axis 30, and the distance between the first supporting part 410 and the first fulcrum 110 is equal to that of the first supporting part 410 and the third fulcrum 210 , and the distance between the second support portion 420 and the second fulcrum 120 is equal to the distance between the second support portion 420 and the fourth fulcrum 220 . The triangular support plane is the most stable support surface, which is easy to level and has a simple structure. Certainly, the first support leg is not limited to be rod-shaped, for example, the first support leg 41 itself is a herringbone bracket that can be opened, and this first support leg 41 can be opened like each vertical edge of two ladders after being opened, Distributed on both sides of the vertical plane passing through the hinge axis 30 .

Further, as shown in FIG. 2 , each of the supporting legs is hinged on the hinge shaft 30 through a hinge structure, and the hinge structure includes: a supporting leg shaft rotatably sleeved on the hinge shaft 30 The sleeve 33 and the supporting leg connecting shaft 34 radially passing through the supporting leg bushing 33, the axis of the supporting leg connecting shaft 34 is consistent with the axis of the hinge shaft 30, but the axis of the supporting leg connecting shaft 34 Vertical to the axis of the supporting leg bushing 33, the supporting leg is hinged on the supporting leg bushing 33 through the supporting leg connecting shaft 34, and the supporting leg is hinged on the hinge hinge shaft through the supporting leg bushing 33 30 on. That is to say, the hinge structure of the present invention is different from the original two-opening hinge. The hinge structure of the present invention realizes the three-opening of the hinge, so that the axis of the supporting leg connecting shaft 34 is perpendicular to the axis of the supporting leg bushing 33 , the direction of rotation has changed, which provides a structural guarantee for the support legs to be hinged on the side of the two-open ladder. The supporting leg bushing 33 can be a circular sleeve or a cuboid sleeve.

Further, as shown in FIG. 3 , the end of the hinge shaft 30 is provided with a limiting boss 305 , and one end of the sleeve 33 is provided with an assembly hole 335 , and the sleeve 33 is sleeved through the assembly hole 335 . On the hinge shaft 30 , and the radial dimension of the limiting boss 305 is larger than the diameter of the assembly hole 335 , so as to prevent the sleeve 33 from sliding out from the end of the hinge shaft 30 . As shown in Figure 2, an open slot 333 is provided on the shaft sleeve 33, and the connecting shaft 34 of the support leg passes through the opening of the open slot 333 vertically, as shown in Figure 2 and Figure 3, the top of the support leg is provided with There is a connecting portion 35 hinged to the connecting shaft of the supporting leg, the connecting portion 35 can rotate around the connecting shaft 34 , and is arranged in the opening slot 33 .

The present invention can also realize the three openings of the two ladders and the supporting legs through another hinge structure. As shown in FIG. Shaft 34, the axis of the supporting leg connecting shaft 34 is perpendicular to the hinge shaft 30, the supporting leg connecting shaft 34 is larger than, equal to or smaller than the hinge shaft 30, in this way, the structure is simpler , but the supporting leg connecting shaft 34 and the hinge shaft 30 have a penetrating relationship, which requires the supporting leg connecting shaft 34 or the hinge shaft 30 to have a certain diameter.

In the above two hinge structures, the two ladders can be connected by an integrated hinge shaft, or can be connected by two split hinge shafts 30 as shown in Figure 1, and the two split hinge shafts The hinge shafts 30 are respectively located on both sides of the ladder, but the axes of the two split hinge shafts 30 are coincident.

The connecting part 35 is a connecting piece or a connecting block, which can rotate around the connecting shaft 34 of the supporting leg. The connecting portion 35 can rotate relative to the connecting shaft 34 of the supporting leg while not moving relative to the shaft sleeve 33 , that is, it is stationary relative to the hinge shaft 30 and only rotates in a vertical plane passing through the hinge shaft 30 . In addition, the connecting portion 35 can also rotate relative to the hinge shaft 30 along with the shaft sleeve 33 , and also rotate relative to the rotating shaft 34 of the supporting leg, so as to realize the free rotation of the supporting leg within a hemispherical range.

The connecting shaft 34 of the supporting leg (the rotating shaft of the supporting leg) can be independent relative to the hinge axis 30, that is, the rotation of the supporting leg can be independent of the opening and retracting of the relative first ladder and the second ladder, and the rotation of the supporting leg The rotation of the first ladder and the second ladder may be asynchronous. For example, when opening and closing of the first ladder and the second ladder fail, or when the supporting legs need to be adjusted individually, the supporting legs can be adjusted individually without adjusting the positions of the first ladder and the second ladder.

Each support leg can freely rotate within the hemisphere range on each side, either around the hinge axis 30 in accordance with the opening direction of the first ladder and the second ladder, or vertically to the first ladder and the second ladder It can also be rotated in any direction, up, down, front, back, left, and right. In this way, in the process of unfolding or retracting the supporting legs, through rotation in different directions and angles, it is possible to avoid complicated on-site working environments and avoid Various obstacles in a narrow space or obstacles in different positions can be quickly and conveniently unfolded or stowed.

Further, as shown in FIG. 1 , the folding ladder further includes: a foldable pedal 5 connected between the first ladder and the second ladder, and the pedal includes: a first pedal hinged by a pedal hinge and the second pedal,

As shown in Figures 4 to 7, the pedal hinge includes: a first chain link 51, a pedal hinge shaft and a second chain link 53, the first chain link and the second chain link are hinged by the pedal hinge shaft, the first The other ends of the chain link and the second chain link are respectively connected to the first ladder and the second ladder. The first chain link 51 may be block-shaped, including: a first pressing contact portion 510 located at one end of the first chain link 51 and a side ear 515 connected to the first pressing contact portion, and the side ear 515 is provided with There is a first shaft hole 513 . The first chain link 51 also includes: a connecting portion 516 at the other end for connecting the first ladder, a connecting hole may be provided in the connecting portion 516 or the connecting portion 516 may be connected with the connecting portion 516 through an adjustment slot 517, Realize the function of folding. The first pressing contact part 510 has an integrated structure, which can transmit the deformation force or supporting force generated by the first pressing contact part 510 to the first ladder, or the deformation force or supporting force generated by the first pressing contact part 510 When a force is applied, the first ladder and/or the second ladder and each supporting leg provide the final support of the deformation force or support force for the first pressing contact portion 510 through the connecting portion.

The second chain link 53 includes: a second pressing contact portion 530 and a second shaft hole 533 disposed on the second pressing contact portion 530, and the pedal hinge shaft 54 passes through the first shaft hole 513 and the second shaft hole 533; the first pressing contact portion 510 and the second pressing contact portion 530 may be in the shape of bumps and may be arranged symmetrically. The second chain link 53 also includes: a connecting portion 536 at the other end for connecting the second ladder, the connecting portion 536 can be integrated with the second pressing contact portion 530, and the connecting portion has the same function as the first chain The joints of the nodes are the same.

As shown in FIG. 4 , the first pedal 511 is connected to the top of the first pressing contact part 510 , and the second pedal 531 is connected to the top of the first pressing contact part 530 .

After the pedal is opened, as shown in FIG. 4 and FIG. 7 , the first pressing contact portion 510 and the second pressing contact portion 530 press against each other on the contact point, that is, the first pressing contact portion 510 The second extrusion contact portion 530 is the end of the block chain link, and this area is the main mutual extrusion deformation area of the two chain links. As shown in FIG. 8 , the first extrusion contact portion 510 includes: a first extrusion contact line a1b1 ; as shown in FIG. 9 , the second extrusion contact portion 530 includes: a second extrusion contact line a2b2 .

The first extruded contact line a1b1 and the second extruded contact line a2b2 face each other and press against the normal line EE at the contact point, and the side ears 515 extend laterally from the first extruded contact portion 510 and The normal line passing through the contact point extends toward the second extrusion contact portion 530, and the first shaft hole 513 is aligned with the second shaft hole 533 and the connecting axis, and the first extrusion contact line a1b1 includes : the first contact a1 at the upper end and the first contact b1 at the lower end, the second extrusion contact line a2b2 includes: the second contact a2 at the upper end and the second contact b2 at the lower end, the first contact a1 at the upper end and the second contact b2 at the lower end The horizontal distance d1 between the first shaft hole 513 (ie the axis AA) is smaller than the horizontal distance d2 between the first contact b1 at the lower end and the first shaft hole 513, and the second contact a2 at the upper end is in contact with the first shaft hole 513. The horizontal distance d3 between the second shaft hole 533 (ie the axis BB) is greater than the horizontal distance d4 between the second contact b2 at the lower end and the second shaft hole 533 .

The first pressing contact part 510 has a horizontal surface 519 passing through the first contact a1, and the first pedal is arranged on the horizontal surface 519 to achieve a horizontal state when the first pedal is opened. Similarly, the second pressing contact part 530 There is a horizontal surface 539 passing through the second contact point a2, and the second pedal is arranged on the horizontal surface 539 to achieve a horizontal state when the second pedal is opened. Wherein, the distance between the first contact a1 and the horizontal surface 519 is greater than the distance between the first shaft hole 513 and the horizontal surface 519, the distance between the second contact a2 and the horizontal surface 539 is greater than the distance between the second shaft hole 533 and the horizontal surface 539, In order to realize the smooth deformation and slight rotation of the first pressing contact part 510 and the second pressing contact part 530 during pressing.

When the pedal is in an unloaded state, for example, as shown in Figures 10 and 11, when the pedal has just been opened but has not applied force to the first chain link 51 and the second chain link 53, the horizontal surface 519 and the horizontal surface 539 cannot When the horizontal state is reached, that is, the angle between the horizontal surface 519 and the horizontal surface 539 and the normal EE at the contact point is not equal to 90 degrees, the first chain link 51 and the second chain link 53 are upturned, and the first pressing contact part 510 and the second The second extrusion contact part 530 is upturned. At this time, the first contact b1 at the lower end is pressed against the second contact b2 at the lower end. There are two situations at this time:

The first type, as shown in Figure 11, the first contact a1 at the upper end and the second contact a2 at the upper end do not press against each other, for example, the first contact a1 at the upper end and the second contact a2 at the upper end are separated, the second contact a1 at the upper end Both the first contact a1 and the second contact a2 have an obvious distance from the normal line EE, forming an opening, and the first extruded contact line a1b1 and the second extruded contact line a2b2 are pressed together by point contact (in the sectional view In the point contact, because each link has a width, the physical contact is a line contact). Further, from the upper end to the lower end, the distance between each point on the first extrusion contact line a1b1 and the first shaft hole gradually increases, the shape of the first extrusion contact line and the second extrusion contact line are the same, symmetrically arranged on the front and rear sides of the first pressing contact portion.

The second type, as shown in Figure 10, has no obvious distance between the first contact a1 and the second contact a2 and the normal line EE, and the first contact a1 on the upper end and the second contact a2 on the upper end are in contact or close to contact. There is no mutual extrusion force between the two, that is, the contact between the two is only on the surface at most, but there is no internal mutual extrusion.

Both of the above can achieve the function of providing support force through extrusion, but the shape, slope or curvature of the first extrusion contact line a1b1 and the second extrusion contact line a2b2 are changed.

When the pedal is in a loaded state, that is, when a force is applied to the first chain link 51 and the second chain link 53, for example, the force can be applied by the gravity of the person, and the upwardly warped first pressing contact portion 510 and the second pressing contact portion 510 The pressing contact portion 530 exerts downward pressure, as shown in FIG. 12 , in addition to pressing against the first contact b1 at the lower end and the second contact b2 at the lower end, the first contact a1 and the second contact a2 are also pressing against each other. The first extruded contact line a1b1 and the second extruded contact line a2b2 are deformed and extruded, and they are pressed together by line contact (the line contact in the sectional view, because each link has a width, the physical contact is surface contact ), at this time, an elastic deformation occurs between the first chain link 51 and the second chain link 53, thereby generating an upward supporting force. That is, the first press-contact part 510 and the second press-contact part 530 provide volume and conditions of press deformation. At the contact point, the connection line between the contact point a1 and the contact point b1 cannot be parallel to the normal line EE, and/or the connection line between the contact point a2 and the contact point b2 cannot be parallel to the normal line EE, otherwise mutual extrusion and deformation cannot be realized. When the load on the pedal is removed, the force exerted on the first pressing contact part 510 and the second pressing contact part 530 from above disappears, and the first pressing contact part 510 and the second pressing contact part 530 Under the action of elasticity, it will recover naturally.

Further, from the upper end to the lower end, the distance between each point on the first extrusion contact line and the first shaft hole gradually increases, and the first extrusion contact line and the second extrusion contact line The shapes are the same, and the first extrusion contact line and the second extrusion contact line are arranged symmetrically.

Further, the first extrusion contact line is a straight line or a smooth curve (for example, an arc line). The first chain link 51 and the second chain link 53 of the present invention can be made of steel or other alloy steels. Since these metal materials have strong elasticity and strength, only a small squeeze space needs to be reserved between the first chain link 51 and the second chain link 53 to provide sufficient supporting force to bear the vertical load. load. The accompanying drawings of the present invention are to show the difference before and after deformation, not the actual proportions and angles, the actual upturned angle between the first chain link 51 and the first ladder, or the upturned or inclined angle between the first pedal and the second pedal is only For example, the first pedal is connected to the first extrusion contact portion 510 through a horizontal surface 519, and the first extrusion contact line a1b1 is, for example, a straight line. When the pedal is not extruded and deformed, the horizontal surface 519 is the first The included angle of the extrusion contact line a1b1 is, for example, 89 degrees, 89.5 degrees, 88 degrees and so on. For example, the distance between the first contact at the upper end and the first shaft hole is smaller than the distance between the first contact at the lower end and the first shaft hole by 0.05 to 0.30 mm, so as to facilitate machining. During processing, the end of the first chain link (i.e. the first extruded contact portion) can be processed into a block-shaped cuboid, and then the end face of the block-shaped cuboid is finished, and a slope is machined with a machine tool. The cross-section of the slope That is, the linear first extrusion contact line. The first pressing contact portion may be a solid metal block. The first extrusion contact portion can also be formed by bending or punching a thin metal plate. In this way, sufficient support can be provided to meet the requirements of extrusion deformation, and material and weight can be saved. For example, a 2mm or 3mm steel plate is used for stamping and then machining to form a linear first extrusion contact line.

The first link can also set rounded corners and transition curves above the first contact at the upper end, or set rounded corners and transition curves c1 below the first contact b1 at the lower end, and the second contact at the lower end of the second link The rounded corners and the transition curve c2 are set under b2, which can reduce wear and increase the thickness and support strength of the first hinge. When the pedal is retracted, fold down from the connecting portion of the first chain link 51 and the first ladder, and the connecting portion of the second chain link 53 and the second ladder, and a gap can be formed between the curve c1 and the curve c2. Provides the required space for folding without hindrance.

The side lugs provide an alignment reference for the first pressing contact part to ensure that the first pressing contact part and the second pressing contact part are pressed simultaneously. There can be one or two side ears, which are symmetrically arranged on the front and rear sides, wherein the second contact at the upper end and the second contact at the lower end in the figure are respectively up and down, and the horizontal direction of the paper where Figure 6 is located is left and right, and the direction perpendicular to the paper plane where Figure 6 is located is the front and rear direction. During the opening or unfolding process of the first chain link 51 and the second chain link 53, when downward pressure is applied, the first chain link and the second chain link provide a vertical support force for the pedal by pressing against each other. The good deformation characteristics of metal reduce the setting of other supports. Since the process of opening and folding is realized only by applying force, there is no need to operate additional components, thus simplifying the steps when the pedal is opened and folded. In addition to pressing against each other, the first chain link and the second chain link are also hinged to each other between the first chain link and the first ladder. In order to allow the pedal to bend when the pedal is opened and retracted, the first chain link 51 The connecting portion 516 of the second link 53 is also provided with an adjusting groove 517, and the connecting portion 516 of the second chain link 53 is also provided with an adjusting groove 537, which are respectively used to adjust the angular relationship or positional relationship with the first piece of ladder or the connection of the first piece of ladder , the first chain link is hinged on the first ladder through the adjustment slot.

Further, as shown in FIG. 1 , the folding ladder further includes: a connecting rod 6 connected between the first ladder, the second ladder, the first support leg and the second support leg, The connecting rod 6 is located under the pedal 5, and the connecting rod 6 includes:

The middle rod 60 is parallel to the hinge axis of the hinge and located under the hinge shaft, and the middle rod 60 is arranged in the middle position between the first ladder and the second ladder;

a first section bar 611 hinged between said middle bar and the first vertical edge 11 of the first ladder;

a second section bar 612 hinged between said middle bar and the second vertical edge 12 of the first ladder;

a third section bar 621 hinged between said middle bar and the first vertical side 21 of the second ladder;

a fourth section bar 622 hinged between said middle bar and the second vertical edge 22 of the second ladder;

a fifth section rod 641 hinged between the first end of the middle rod and the first support leg 41;

The sixth section rod 642 is hinged between the second end of the middle rod and the second supporting leg 42 .

The middle rod and the above-mentioned joint rods can be straight rods. The middle rod acts as a central hub to provide rotational support for the above-mentioned section rods, and the middle rod can also increase the connection strength between the first support leg 41 and the second support leg 42. In addition, the middle rod connects each piece of the ladder The vertical sides are all connected, which increases the connection strength of each vertical side of each ladder and the connection strength between the first support leg 41 and the second support leg 42 . Preferably, when the ladder is unfolded, the middle rod and the above-mentioned section rods are at or close to the middle position of the ladder, for example, the plane formed by the middle rod and the center line of each vertical side is a horizontal plane, so that the stress of the ladder is reasonable.

For example, one end of the first joint 611, the second joint 612, the third joint 621, the fourth joint 622, the fifth joint 641 and the sixth joint 642 are fixedly connected to the middle pole respectively, and the first joint The other ends of the rod 611 , the second rod 612 , the third rod 621 , the fourth rod 622 , the fifth rod 641 and the sixth rod 642 are hingedly connected to the vertical sides of the ladders respectively.

Each of the first section bar 611 to the sixth section bar 642 may be provided with an adjustment slot for adjusting the change of the connection position or the change of the angle. For example, the fifth section rod can be provided with an adjustment slot for adjusting the hinge position of the fifth section rod and the first support leg 41 or adjusting the hinge position of the fifth section rod and the middle rod, thereby controlling the opening angle of the support legs . Various suitable structures in the prior art can be adopted for the adjustment slot, for example, it is arranged at one end close to the first support leg 41 . In the same way, the sixth pole can adopt a similar structure to achieve the symmetry of the structure and force of the ladder.

Further, the first section bar 611, the third section bar 621, the first vertical side 11 of the first piece of ladder and the first vertical side 21 of the second piece of ladder are coplanar and are all perpendicular to the The middle bar 60; the second section bar 612, the fourth section bar 622, the second vertical side 12 of the first ladder and the second vertical side 22 of the second ladder are coplanar and uniform Vertically the middle pole. In this way, the middle rod can realize vertical support to the vertical sides of each ladder and each support leg, and will not be easily bent. In addition, it is also possible to set a stop bar on each ladder higher than the step or between two ladders. The stop bar can be clamped between the vertical sides of the ladder through a convenient clamping method. After the stop bar is unfolded, it can be positioned at the horizontal In-plane, so that when in use, the stop bar forms a barrier to prevent people's legs from stepping out by mistake, preventing misoperation.

The above descriptions are only illustrative specific implementations of the present invention, and are not intended to limit the scope of the present invention. Because the various components of the present invention can be combined with each other under the condition of no conflict, any equivalent changes and modifications made by any person skilled in the art without departing from the concept and principle of the present invention shall belong to the protection of the present invention. range.

Claims (10)

1. folding ladder, described folding ladder comprises: by hinge hinge hinged first ladder and second ladder, it is characterized in that,

The first ladder comprises: the first vertical edge (11) that lays respectively at the first ladder of both sides of the edge, second vertical edge (12) of first ladder and be connected to horizontal ladder between second vertical edge (12) of the first vertical edge (11) and first ladder, second ladder comprises: the first vertical edge (21) that lays respectively at second ladder of both sides of the edge, second vertical edge (22) of second ladder and be connected to horizontal ladder between second vertical edge (22) of the first vertical edge (21) and second ladder, the lower end of first vertical edge (11) of described first ladder have the first fulcrum that is supported on the work plane, second vertical edge (12) of described first ladder has the second fulcrum that is supported on the work plane, first vertical edge (21) of described second ladder has the 3rd fulcrum that is supported on the work plane, second vertical edge (22) of described second ladder has the 4th fulcrum that is supported on the work plane, described the first fulcrum and the 3rd fulcrum are positioned at a side of folding ladder, the second fulcrum and the 4th fulcrum are positioned at the opposite side of folding ladder

Described folding ladder also comprises: be hinged on the supporting leg on the described hinge hinge, described supporting leg is two, be respectively the first supporting leg and the second supporting leg, described the first supporting leg is positioned at the outside on the formed plane of the first vertical edge (21) of first vertical edge (11) of first ladder and second ladder, and described the second supporting leg is positioned at the outside on the formed plane of the second vertical edge (22) of second vertical edge (12) of first ladder and second ladder.

2. folding ladder as claimed in claim 1, it is characterized in that, described the first supporting leg has the first support portion that is supported on the work plane, described the second supporting leg has the second support portion that is supported on the work plane, described the first support portion, described the first fulcrum and the 3rd fulcrum form the first polygon supporting plane, described the second support portion, described the second fulcrum and the 4th fulcrum form the second polygon supporting plane, and described the first polygon supporting plane and the second polygon supporting plane are symmetrical arranged.

3. folding ladder as claimed in claim 2, it is characterized in that, described the first supporting leg and the second supporting leg are support bar, described the first support portion and the second support portion are the strong point, described the first polygon supporting plane and the second polygon supporting plane are isosceles triangle, the distance of described the first support portion and described the first fulcrum equals the distance of described the first support portion and described the 3rd fulcrum, and the distance of described the second support portion and described the second fulcrum equals the distance of described the second support portion and described the 4th fulcrum.

4. folding ladder as claimed in claim 1 is characterized in that, described supporting leg is hinged on the hinge hinge by articulated structure,

Described articulated structure comprises: that can rotate is set in the supporting leg axle sleeve on the described hinge hinge and radially passes the supporting leg connecting axle of described supporting leg axle sleeve, the axis of the vertical described supporting leg axle sleeve of the axis of described supporting leg connecting axle, described supporting leg is hinged on the supporting leg axle sleeve by the supporting leg connecting axle, and described supporting leg is hinged on the described hinge hinge by described supporting leg axle sleeve;

Perhaps, described articulated structure comprises: that can rotate is located in supporting leg connecting axle in the described hinge hinge, the vertical described hinge hinge of the axis of described supporting leg connecting axle.

5. folding ladder as claimed in claim 4, it is characterized in that, the end of described hinge hinge is provided with positive stop lug boss, one end of described axle sleeve is provided with pilot hole, described axle sleeve is set on the described hinge hinge by pilot hole, and the radial dimension of described positive stop lug boss is greater than the aperture of pilot hole, the other end of described axle sleeve offers open slot, described supporting leg connecting axle vertically passes the opening of open slot, the top of described supporting leg is provided with the connecting portion hinged with described supporting leg connecting axle, and described connecting portion can be arranged in the described open slot rotationally.

6. folding ladder as claimed in claim 1 is characterized in that, described folding ladder also comprises:

Be connected to the pedal that can fold between described first ladder and second ladder, described pedal comprises: by pedal hinge hinged the first pedal and the second pedal,

Described pedal hinge comprises: the first chain link, pedal hinge and the second chain link, it is hinged that described the first chain link and the second links are crossed the pedal hinge, described the first chain link comprises: the first extruding contact site and picking up the ears of being connected with described the first extruding contact site, describedly pick up the ears to be provided with the first axis hole, described the second chain link comprises: the second extruding contact site and the second axis hole that is arranged on described the second extruding contact site, and described pedal hinge passes described the first axis hole and described the second axis hole;

Described the first pedal is connected to the top of described the first extruding contact site, and described the second pedal is connected to the top of described the first extruding contact site;

Described the first extruding contact site and described the second extruding contact site are pressed on the contact position mutually, described the first extruding contact site comprises: the first extruding contact wire, described the second extruding contact site comprises: the second extruding contact wire, described the first extruding contact wire and described the second extruding contact wire are mutually faced and are pressed on the normal of contact position, described picking up the ears extended to the direction of described the second extruding contact site from the normal that extends laterally and pass through described contact position of described the first extruding contact site, and, described the first axis hole aligns with the second axis hole and pedal hinge, described the first extruding contact wire comprises: the first contact a1 of upper end and the first contact b1 of lower end, described the second extruding contact wire comprises: the second contact a2 of upper end and the second contact b2 of lower end, between the first contact of described upper end and described the first axis hole apart from d1 less than between the first contact of described lower end and described the first axis hole apart from d2, between the second contact of described upper end and described the second axis hole apart from d3 greater than between the second contact of described lower end and described the second axis hole apart from d4.

7. folding ladder as claimed in claim 6 is characterized in that,

Described pedal opens and is under the no-load condition, and the first contact a1 of described upper end and the second contact a2 of upper end compress mutually, and described the first extruding contact wire and the second extruding contact wire are pressed on together by contacting;

Described pedal opens and is under the load condition, the first contact a1 of described upper end and the second contact a2 of upper end compress mutually, the first contact b1 of described lower end and the second contact b2 of lower end compress mutually, and described the first extruding contact wire contacts by line with the second extruding contact wire and is pressed on together.

8. folding ladder as claimed in claim 7, it is characterized in that, from the upper end to the lower end, each point on described the first extruding contact wire and the distance between described the first axis hole become large gradually, described the first extruding contact wire is identical with the second extruding contact wire shape, described the first extruding contact wire and the second extruding contact wire are symmetrical arranged, described the first extruding contact site has the first horizontal surface (519) through the first contact a1, the first pedal is arranged on described the first horizontal surface, the second extruding contact site has the second horizontal surface (539) through the second contact a2, the second pedal is arranged on described the second horizontal surface, the distance of described the first contact a1 and described the first horizontal surface (519) is greater than the distance of described the first axis hole (513) with described horizontal surface (519), and the distance of the second contact a2 and the second horizontal surface (539) is greater than the distance of described the second axis hole (533) with described the second horizontal surface (539).

9. folding ladder as claimed in claim 8, it is characterized in that, described the first extruding contact wire is straight line or smooth curve, between the first contact of upper end and described the first axis hole is 0.05 to 0.30mm apart from d1 less than the first contact of lower end and the numerical value apart from d2 between described the first axis hole, and described two supporting legs, described first ladder and second ladder all are telescopic.

10. folding ladder as claimed in claim 1, it is characterized in that, described folding ladder also comprises: be connected to the connecting rod (6) between described first ladder, described second ladder, described the first supporting leg and the second supporting leg, described connecting rod is positioned under the pedal, and described connecting rod comprises:

Intermediate bar (60), parallel hinge hinge also is positioned under the described hinge hinge, and intermediate bar (60) is arranged on the center position between first ladder and second ladder;

Be hinged on the first pole (611) between first vertical edge (11) of described intermediate bar and first ladder;

Be hinged on the second pole (612) between second vertical edge (12) of described intermediate bar and first ladder;

Be hinged on the three pair rod (621) between first vertical edge (21) of described intermediate bar and second ladder;

Be hinged on the 4th pole (622) between second vertical edge (22) of described intermediate bar and second ladder;

Be hinged on the first end of described intermediate bar and the 5th pole (641) between the first supporting leg (41);

Be hinged on the second end of described intermediate bar and the 6th pole (642) between the second supporting leg (42);

First vertical edge (11) of described the first pole (611), described three pair rod (621), described first ladder and all vertical described intermediate bar (60) coplanar with first vertical edge (21) of described second ladder; Second vertical edge (12) of described the second pole (612), described the 4th pole (622), described first ladder and all vertical described intermediate bar coplanar with second vertical edge (22) of described second ladder.

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