WO2018130166A1

WO2018130166A1 - Folding stepladder

Info

Publication number: WO2018130166A1
Application number: PCT/CN2018/072180
Authority: WO
Inventors: 黄崇华
Original assignee: 黄崇华
Priority date: 2017-01-15
Filing date: 2018-01-11
Publication date: 2018-07-19

Abstract

A folding stepladder, comprising two ladders that are hingedly connected and ladder joints (10). The two ladders that are hingedly connected are respectively a first ladder (11) and a second ladder (12). The ladder joints (10) are used for hingedly connecting the first ladder (11) and the second ladder (12). The ladder joints (10) each comprises a first locking tooth part (1) and a second locking tooth part (2). The first locking tooth parts (1) are fixedly connected to the first ladder (11); the second locking tooth parts (2) are rotatably connected to the second ladder (12). The first ladder (11) and the second ladder (12) are rotatably connected by means of first hinge shafts 5. The first locking tooth parts (1) and the second locking tooth parts (2) are engaged with each other; and the first locking tooth parts (1) and the second locking tooth parts (2) implement unidirectional locking. By means of gear-based locking, the stepladder is able to implement continuous angle adjustment, thereby adapting to the change of an opening angle of a stepladder.

Description

Folding ladder

The present invention claims the priority of the following Chinese patents:

Application No.: cn 201710026893.0, invention name: ladder joint;

Application No.: cn201710059018.2, title of the invention: folding ladder with locking device.

Technical field

The invention relates to a folding ladder.

Background technique

In the existing folding ladder, the two ladders can rotate relative to each other to form a certain angle. However, the joints between the two ladders of the existing folding ladder are only positioned by simple snap positioning, and only a few buckles are set, generally three, so the adjustment angle between the two ladders There are only a limited number, generally three, which is inconvenient to adjust and affect the use of ladders.

Summary of the invention

The invention provides a folding ladder to solve the problem that the existing ladder angle adjustment is inconvenient.

To this end, the present invention provides a folding ladder, the folding ladder comprising: two hinged ladders, respectively a first ladder and a second ladder, and for articulating the first ladder and the second ladder a ladder joint, the ladder joint includes:

a first locking tooth fixedly connected to the first ladder;

a second locking tooth connected to the second ladder;

The first ladder and the second ladder are rotatably connected by the first hinge shaft;

The first locking teeth and the second locking teeth mesh with each other, and the first locking teeth and the second locking teeth are one-way locking.

The invention adopts the gear locking, and the two locking teeth are respectively connected with the two ladders, so that the variation of the adjustment angle and the continuity of the adjustment can be realized, and thus the change of the opening angle of the folding ladder can be adapted.

Further, the present invention adopts a column spring to realize automatic locking, thereby avoiding the need for the traditional locking to align the snaps of the two ladders, thereby reducing the risk of the ladder opening. Furthermore, the present invention uses the column spring and the torsion spring to jointly return the second locking teeth. First, the double insurance is formed, and the wear of the column spring and the torsion spring is reduced, thereby increasing the service life of the entire joint.

Furthermore, the present invention uses a wire to control the position of the second locking teeth, thereby controlling the locking between the two locking teeth, so that it is not necessary to climb to the joint of the ladder like the conventional snap locking, that is, the ladder is the highest. The connection of the points to lock or unlock the buckle, the present invention can operate the pull wire at the lower part of the ladder to lock or unlock the two ladders, avoiding the need to climb to the apex of the ladder each time the ladder is folded or folded. It reduces the chance of accidents, increases safety, and facilitates quick collection.

Further, the first lateral support rod and the ladder body, that is, the two hinged ladders are respectively connected by the first link and the second link, thereby increasing the stability of the first lateral support rod and increasing the number The stability and strength of the internal connection between the lateral support bar and the two hinged ladders, and in turn, the first lateral support bar and the ladder body, ie the two hinged ladders, are locked by the first locking device Tight, thereby avoiding the first lateral support rod opening at will in use, reducing safety hazards.

Further, the first end of the first link is fixedly connected to the first ladder, and the second end of the first link is slidably coupled to the first lateral support rod; the first lock The tensioning device is disposed on the first lateral support rod, so that only the first sliding support device can be disposed on the first lateral support rod, so that the first ladder and the second ladder can be avoided. The chute or track for sliding the link reduces the manufacturing and installation steps, and can control the first link and the second link respectively by operating the first locking device on the first lateral support bar. Do two things at a time, to achieve fast control and lock.

Further, by the first locking device having the cam, the bolt and the spring returning structure, the quick adjustment, the quick switching, the firm locking, the automatic locking effect, and the safety can be realized.

Further, the first locking device is located below the first link and the second link, so that after the worker comes down from the ladder, the lock or unlock can be realized on the ground without having to climb to the ladder. To lock or unlock, to ensure the stability and safety of the ladder before the ladder, to ensure the convenience of the ladder after the ladder.

Furthermore, due to the stable lateral support and reliable locking, and the flexible rotation of the lateral support bars, the folding ladder of the present invention is particularly suitable for use in the field and in uneven terrain.

DRAWINGS

1 is a perspective structural view showing a first angle of a first folding ladder according to an embodiment of the present invention;

2 is a schematic perspective structural view of a second angle of a first folding ladder according to an embodiment of the present invention; wherein, in order to show the structure of the ladder joint, a part of the structure of the first ladder and the second ladder is hidden;

3 is a schematic perspective structural view of a second folding ladder according to an embodiment of the present invention;

4 is a schematic structural view of a first locking device according to an embodiment of the present invention;

Figure 5 is a schematic view showing the external structure of a ladder joint according to an embodiment of the present invention;

Fig. 6 is a schematic view showing the internal structure of a ladder joint according to an embodiment of the present invention.

Description of the reference numerals:

11. The first ladder; 12, the second ladder; 13, the first lateral support rod; 14, the second lateral support rod;

131, first section pole; 132, second section pole;

151, a first link; 152, a second link; 153, a third link; 154, a fourth link; 111, a first vertical side; 112, a second vertical side;

10, the ladder joint; 1, the first locking teeth; 2, the second locking teeth; 3, the first outer box; 4, the second outer box; 5, the first hinge shaft; 6, the pull line; 7, the second Hinge shaft; 8, spring seat; 9, column spring; 20, threading groove; 30, rivet; 32, second end of the first outer box; 42, second end of the second outer box; 45, guiding device; Connection;

27, the first locking device; 270, the first locking sleeve; 21, the adjusting bolt; 22, the hinge shaft; 23, the eccentric cam; 24, the handle; 25, the locking return spring; 201, the opening.

Detailed ways

In order to more clearly understand the technical features, objects and effects of the present invention, the present invention will be described with reference to the accompanying drawings.

As shown in Figures 1, 2 and 3, the folding ladder of the embodiment of the present invention comprises: two hinged ladders, and a ladder joint 10 for hingedly connecting the two hinged ladders. The two hinged ladders are a first ladder 11 and a second ladder 12, respectively, and the ladder joint 10 includes:

a first locking tooth 1 fixedly connected to the first ladder 11;

The second locking tooth 2 is rotatably coupled to the second blade 12, that is, the second locking tooth 2 is rotatable relative to the second blade 12;

The first ladder 11 and the second ladder 12 are rotatably connected by the first hinge shaft 5;

The first locking tooth 1 and the second locking tooth 2 mesh with each other, and the first locking tooth 1 and the second locking tooth 2 are one-way locking, for example, the first ladder 11 and the second piece of the ladder 12 are close together, the first locking tooth 1 and the second locking tooth 2 may form a gear transmission, but if the first piece of the ladder 11 and the second piece of the ladder 12 are away from each other, the angle becomes larger When the first locking teeth 1 and the second locking teeth 2 are locked, the ladder is prevented from sliding outward during use, and after the unlocking, the first ladder 11 and the second ladder 12 can be separated from each other.

Further, as shown in FIG. 5 and FIG. 6, the first locking tooth 1 is a semi-ring gear, and since the maximum opening angle of the ladder is 180 degrees, the use of the semi-ring gear is sufficient to satisfy the maximum opening of the ladder. Angle, thereby reducing cost, reducing weight, and making the space more compact; the axis of the semi-ring gear is concentric with the first hinge shaft 5, and the second locking tooth 2 has two ends, respectively a second lock a first end of the tightening tooth and a second end of the second locking tooth, the second locking tooth further has an inner side surface and an outer side surface, the first end of the second locking tooth and the second piece of the ladder pass the first The two hinge shafts 7 are hingedly connected, the semi-ring gears are located between the first hinge shaft 5 and the second hinge shaft 7; the second end of the second locking teeth is pressed against the returning action The inner side of the second locking tooth 2 is a circular arc shape, and the circular arc shape is coaxial with the gear of the first locking tooth or with the first hinge shaft, so that the second locking tooth 2 and the second locking tooth 2 a locking tooth is engaged, and an inner side of the second locking tooth is provided with a engaging tooth that meshes with the semi-annular gear, and the column spring 9 is pressed against the first The outer surface of the second end of the locking teeth, in order to achieve a one-way lock.

In the case of no external disturbance of the person, the column spring (column spring) 9 causes the second locking tooth 2 to be automatically pressed against the first locking tooth 1 when the second locking tooth 2 is opposite to the first locking tooth When the inner 1 is rotated inward, the second locking tooth 2 receives an inward force, that is, the second locking tooth 2 receives a force from the second end of the second locking tooth to the first end of the second locking tooth. At this time, since the first end of the second locking tooth is a fixed end, the first end of the second locking tooth cannot move, thereby preventing the second locking tooth 2 from rotating inward relative to the first locking tooth 1 Preventing the two ladders from opening; but for the second locking teeth 2 to rotate outward relative to the first locking teeth 1, at this time, the second locking teeth 2 are subjected to the outward thrust of the first locking teeth 1, the second locking The second end of the tightening tooth is a non-fixed end. Since the second locking tooth 2 receives the outward force of the first locking tooth 1 by more than the restoring force of the column spring 9, although the restoring force of the column spring 9 is not, Affecting the second locking tooth 2 to rotate or move outward relative to the first locking tooth 1 , so that the pressure of the second locking tooth 2 pressed against the first locking tooth 1 is relatively rotated with the second locking tooth 2 and Not contradictory Thus relative rotation of the second locking tooth 2 is not affected, i.e., when the two ladder collapsed, does not affect the joint collapsed or stowed ladder.

Further, as shown in FIG. 5 and FIG. 6, the ladder joint 10 further includes: a first outer casing 3 wrapped around the first locking teeth 1, and a second locking covering a second outer casing 4 other than the teeth 2, the first outer casing 3 and the second outer casing 4 are hinged by the first hinge shaft 5; the first outer casing 3 and the second outer casing 4 may Relative rotation, forming different angles to form different opening angles of the ladder;

The first outer casing 3 is fixedly connected to the first ladder 11 and the second outer casing 4 is fixedly connected by the second ladder 12;

The first locking tooth 1 is fixedly connected to the first outer box 3, and the second locking tooth 2 is hingedly connected to the second outer box 4 by the second hinge shaft 7; The first locking tooth 1 is fixedly connected to the first piece of ladder 11 through the first outer box 3; the second locking tooth 2 is rotatably connected to the second outer box by a second hinge shaft 7 and The second ladder 12 is connected, and the second outer casing 4 is further provided with a spring seat 8 for supporting the column spring 9. The first outer casing 3 and the second outer casing 4 mainly serve to close and protect the respective locking teeth, respectively, and provide fixing and support for the respective locking teeth; and can also provide support for the column spring 9.

Further, the second hinge shaft 7 is sleeved with a torsion spring (not shown) for returning the second locking teeth 2. The torsion spring also acts as a resilience, enabling the two locking teeth to be automatically locked without interference from external forces. Wherein, the second hinge shaft 7 is disposed on the second outer casing 4, the bottom of the second hinge shaft 7 protrudes from the second locking tooth 2 and exposes the second outer casing 4, and the top of the second hinge shaft 7 protrudes from the second The locking teeth 2 are respectively sleeved on the bottom of the second hinge shaft 7 and the top of the second hinge shaft 7, respectively, which are respectively sleeved on both ends of the second hinge shaft 7, which can restore the function on the one hand, and On the one hand, it can also play the role of axial positioning and buffering of the second hinge shaft 7, and has a good balance effect.

Further, the first outer box 3 has a first end of the first outer box and a second end 32 of the first outer box, and the second outer box 4 has a first end and a second outer side of the second outer box a second end 42 of the cartridge, the first end of the first outer casing being hinged to the first end of the second outer casing; the second end 32 of the first outer casing being coupled to the first ladder 11 The second end 42 of the second outer casing is fixedly connected to the second ladder 12;

The ladder joint 10 further includes: a pull wire 6 connecting the second end of the second locking tooth 2, the pull wire 6 being located in the second outer box 4 and extending out of the second outer box The end 42 is connected to the outer surface of the second ladder (the second ladder or its vertical side is hollow, the wire is routed from the inside of the vertical side, and the side wall of the second ladder or the vertical side is pierced The outer surface of the second ladder is provided with a wrench connecting the wire; after the second end of the second locking tooth 2 is locked with the first locking tooth 1, the wire can overcome the pressure of the torsion spring. Pulling the second end of the second locking tooth 2 to disengage the second end of the second locking tooth 2 from the first locking tooth 1, thereby releasing the locking with the first locking tooth 1, so that After the second end of the second locking tooth 2 is locked with the first locking tooth 1, when the wire is not applied, the second end of the second locking tooth 2 and the first locking tooth 1 are Keeping the bite and maintaining the lock, at this time, the two ladders cannot be opened outward, but the two ladders can be retracted inward; since the second end 42 of the second outer casing is fixedly connected to the second ladder 12, This This is equivalent to extending the control length of the second locking teeth 2, which can be extended from the locking teeth to the second ladder, reducing the control height. The position of the second locking tooth is controlled by the wire to control the locking between the two locking teeth, so that it is not necessary to climb to the joint of the ladder like the traditional snap locking, that is, the connection point of the highest point of the ladder In order to lock or unlock the buckle, the present invention can operate the cable at the lower part of the ladder to lock or unlock the two ladders, avoiding the need to climb to the apex of the ladder each time the ladder is folded or folded, thereby reducing the accident. The chance of occurrence increases safety and is quick and easy to close.

Further, the wire 6 is connected to the second end of the second locking tooth 2 through the column spring 9, so that the setting is ingenious, and the problem that the wire is wound around other components does not occur. The second end of the second locking tooth 2 may be provided with a threading groove 20 for fixing the wire to the second end of the second locking tooth 2.

Further, the second outer casing 4 is further provided with a guiding device 45 for guiding the pulling wire 6, and the direction of the pulling wire 6 can be adjusted. The guiding device 45 is, for example, a guide post.

Further, the semi-ring gear (180 degrees) is provided with 6 to 90 teeth, for example, 10, 20, 30, 40, 50, 60, 70, 80, 90 uniformly distributed teeth, or 20- 30 teeth, 30-40 teeth, 40-50 teeth, 50-60 teeth, 70-80 teeth, 80-90 teeth, which can achieve continuous multi-angle fine adjustment in the range of 180 degrees. Can meet the various needs of the ladder open.

Further, the second locking tooth 2 is a rack having a circular inner side surface, and the number of teeth of the rack is 3 to 6. Since the first locking tooth 1 has a plurality of teeth, it can be rotated by 180 degrees. Therefore, the second locking tooth 2 only needs a few teeth, and the length of the second locking tooth 2 can be made smaller, and the number of teeth can be It is less done, easy to manufacture, process and install, and to reduce the quality of the ladder.

Further, the semi-ring gear is fixed on the first outer box 3 by two or more rivets 30, for example, by three rivets, so that the first locking teeth 1 are fixed and stable, and are not relatively first. The outer box 3 is rotated.

Further, the first outer box 3 and the second outer box 4 are both upper and lower split structures, and mainly protect and close the upper and lower ends of the first locking teeth 1 and the second locking teeth 2, An outer box 3 and the second outer box 4 are provided with openings at the mutual engagement of the first locking teeth 1 and the second locking teeth 2 so as not to affect the engagement and rotation of the two locking teeth, first The outer box 3 and the second outer box 4 are equally divided into upper and lower halves so as to form the first locking teeth 1 and the second locking teeth 2 to form a closure.

The ladder joint of the invention can realize stable locking and multi-angle precise adjustment of the folding ladder. The invention adopts the cable to control the locking, so that it is not necessary to climb to the joint of the ladder, that is, the joint of the highest point of the ladder, to lock or unlock the buckle, as in the conventional snap locking, the present invention can operate the cable at the lower part of the ladder. Thereby locking or unlocking the two ladders avoids the need to climb to the apex of the ladder each time the ladder is folded or folded, which reduces the chance of accidents, increases safety, and facilitates quick retraction. The folding ladder of the invention has firm locking and is suitable for various terrains, including uneven mountain areas.

Further, as shown in FIG. 1 and FIG. 2, the folding ladder of the present invention further comprises: lateral support bars respectively disposed on two sides of the two ladders, wherein the lateral support bars are respectively disposed on the two ladders a first lateral support bar 13 on the side, and a second lateral support bar 14 disposed on the second side of the two ladders; the first lateral support bar 13 is located in the rectangular parallelepiped formed by the first ladder 11 and the second ladder 12 In addition to the space or the ladder-shaped space, the second lateral support bar 14 is also located outside the cuboid space or the ladder-shaped space formed by the first and

second ladders

11 and 12, and the folding ladder further includes:

a first link 151 movably coupled between the first blade 11 and the first lateral support bar 13; for example, the first link 151 is slidably coupled by a universal joint or a hinge (without adjusting bolts) Between the first piece of ladder 11 and the first lateral support rod 13;

a second link 152 movably coupled between the second blade 12 and the first lateral support bar 13; for example, the second link 152 is slidably coupled by a universal joint or a hinge (without adjusting bolts) Between the second piece of ladder 12 and the first lateral support rod 13;

Locking the first locking device 27 of the first connecting rod and/or the second connecting rod, connecting the first connecting rod and/or the second connecting rod; the first connecting rod or the second connecting rod may be respectively used A locking device is locked, and a locking device can be shared;

The first locking device 27 is disposed on the first piece of ladder, or on the second piece of ladder, or on the first lateral support rod. The first lateral support rod and the ladder main body, that is, the two hinged ladders are respectively connected by the first connecting rod and the second connecting rod, thereby increasing the stability of the first lateral supporting rod and increasing the first side The stability and strength of the internal connection between the support rod and the two hinged ladders, and in turn, the first lateral support rod and the ladder body, ie the two hinged ladders, are locked by the first locking device, Thereby, the first lateral support rod is prevented from being opened at will in use, which reduces safety hazards.

Further, the folding ladder further includes:

a third link 153, movably connected between the first blade 11 and the second lateral support bar 14 , for example by a universal joint or a hinge (without adjusting bolts);

The fourth link 154 is movably coupled between the second blade 12 and the second lateral support bar 14 by, for example, a universal joint or a hinge (without adjusting bolts);

Locking the third link and/or the second link of the fourth link, connecting the third link and/or the fourth link; the second locking device is disposed at the On a ladder, or on the second ladder, or on the second lateral support rod.

That is, the sides of the ladder are symmetrical, and the structure of the lateral support rods and the locking devices on both sides is the same to achieve symmetry of the force.

Further, as shown in FIG. 1, the first link 151 has two ends, which are respectively a first end (upper end) of the first link and a second end (lower end) of the first link, the first a first end of the connecting rod is fixedly coupled to the first ladder 11 , a second end of the first connecting rod is slidably coupled to the first lateral supporting rod; and the second connecting rod 152 has two a first end (upper end) of the second link and a second end (lower end) of the first link, the first end of the second link is fixedly connected to the second ladder, a second end of the two links is slidably coupled to the first lateral support bar; the first locking device 27 is slidably disposed on the first lateral support bar 13, the first locking The device 27 simultaneously connects the first link 151 and the second link 152.

In this way, it is only necessary to provide the slidable first locking device 27 on the first lateral support rod 13, so that the sliding groove or the track for the sliding of the connecting rod can be avoided on the first ladder and the second ladder. The manufacturing and installation steps are reduced, and the operation of the first locking device on the first side to the support rod, and the control of the first link and the second link at the same time, can achieve two-fold, fast control and lock tight.

Further, as shown in FIG. 4, the first locking device 27 includes:

The first locking sleeve 270 can be elastically sleeved on the first lateral support rod 13. The first locking sleeve 270 can be respectively provided with a rotating shaft connected to the first connecting rod and connected with the second connecting rod. The first shaft and the second link are independently rotatable relative to the first locking sleeve 270; the first locking sleeve is annular with an opening 201, such as a rectangular ring having an opening 201, the first lock The sleeve 270 may be provided on the outer wall of the opposite side of the opening 201 with a lug for respectively providing a rotating shaft connected to the first connecting rod and a rotating shaft connected to the second connecting rod;

4 is a schematic view showing the locking principle of the first locking device, the first locking sleeve has a first locking sleeve first end and a first locking sleeve second end; the opening 201 is disposed in the Between the first end of the first locking sleeve and the second end of the first locking sleeve; when the opening 201 of the first locking sleeve 270 is relaxed, the inner wall of the first locking sleeve 270 and the first lateral support rod 13 There is a gap between the outer walls, the first locking sleeve 270 can slide on the first lateral support rod 13; when the opening of the first locking sleeve 270 is tightened, the inner wall of the first locking sleeve 270 and the first The gap between the outer walls of the lateral support rods 13 is eliminated or reduced, and the inner wall of the first locking sleeve 270 is in contact with or abuts against the outer wall of the first lateral support rods 13, which form a static friction, so that the first lock a tight sleeve 270 is fixed on the first lateral support rod 13 to form a locking;

An adjusting bolt 21 for controlling the size of the opening 201, penetrates the opening 201, and is connected between the first end of the first locking sleeve 270 and the second end of the first locking sleeve; the length of the adjusting bolt 21 The direction is perpendicular to the longitudinal direction of the first lateral support rod 13; the first end of the adjusting bolt is a nut, and the end end of the adjusting bolt is a screw end;

a hinge shaft 22 of the locking device is disposed at a tail end of the adjusting bolt 21, and a longitudinal direction of the hinge shaft 22 is perpendicular to a longitudinal direction of the adjusting bolt and parallel to a longitudinal direction of the first lateral supporting rod 13;

An eccentric cam 23 is hinged on the hinge shaft 22 of the locking device and an outer edge of the eccentric cam 23 is pressed against an outer side surface of the second end of the first locking sleeve;

a handle 24, connected to the eccentric cam 23;

The locking return spring 25 is sleeved on the adjusting bolt 21 and located between the first end of the first locking sleeve and the second end of the first locking sleeve.

When the handle 24 is pulled, the eccentric cam 23 is rotated about the hinge shaft 22. During the rotation of the eccentric cam 23, the advancement and retreat of the adjusting bolt 21 is driven to adjust the size of the opening 201. Therefore, when the opening of the first locking sleeve 270 is opened, When tightened, the gap between the inner wall of the first locking sleeve 270 and the outer wall of the first lateral support rod 13 is eliminated or reduced, and the inner wall of the first locking sleeve 270 is opposite to the outer wall of the first lateral support rod 13. Fitted or abutted, the two form a static friction such that the first locking sleeve 270 is fixed to the first lateral support rod 13 to form a locking of each link. The locking return spring 25, for example a compression spring, acts as an automatic return to facilitate automatic locking. Through the first locking device with cam, bolt and spring return structure, fast adjustment, fast conversion, firm locking and automatic locking effect can be realized, which increases safety.

Further, as shown in FIG. 4, the inner wall of the first locking sleeve 270 is a rectangle having an opening, and the outer side surface of the first lateral support rod 13 is rectangular, that is, the first locking sleeve 270 has an opening. The annular shape of the rectangle, the first lateral support rod 13 is a solid rod or a hollow rod or tube. For example, the solid rod is selected in the present invention, and the adjusting bolt 21 is disposed in the two protruding side walls at the opening of the first locking sleeve 270. (In Fig. 4, the two side walls of the opening protrude upward), and the two protruding side walls are vertically adjusted to the axial direction of the bolt 21, therefore, the adjusting bolt 21, for example, the nut of the adjusting bolt, and the two sections The protruding side wall is a contact between the plane and the plane. The locking is stronger than the locking of the bolt and the circular tube, the contact area is increased, the locking area is increased, and the first lateral support rod 13 is a rectangular rod or The rectangular tube can withstand a larger locking force than the circular tube, and even if there is a gap, it is not easily deformed and is not easily broken. The bolt and the circular tube are locked. Since the head (nut) or the tail of the bolt acts on the circular side, the contact between the bolt and the circular tube is not a plane contact. Therefore, on the one hand, the circular tube has The notch is easily bent under the tightening action of the bolt; on the other hand, the contact surface is not flat, and the bolt and the circular tube are easily worn, and it is easy to be damaged after a long time.

Further, the first locking device 27 is located below the first end of the first link 151 and below the first end of the second link 152. In this way, after the worker comes down from the ladder, it can be locked or unlocked on the ground. It is not necessary to climb to the ladder to lock or unlock, which ensures the stability and safety of the ladder before the ladder, ensuring the ladder. The convenience of the ladder is put away.

Further, the first ladder 11 and the second ladder 12 are hingedly connected by a first hinge, the first ladder includes: a first vertical side 111, a second vertical side 112, and a connection a plurality of lateral sides between a vertical side and a second vertical side, the first end of the first link is fixedly coupled to the first vertical side of the first ladder, the first link 151 The distance between the first end (upper end) and the first hinge shaft is 1/8 to 1/2 of the distance between the first end of the first link and the bottom end (ground end) of the first ladder . In this way, the position of the first connecting rod is set reasonably, and the angle adjustment and the length adjustment can be performed, so that the first connecting rod can bear the force reasonably, share the overall force of the ladder, and reduce the stress on other parts. In particular, the distance between the first end (upper end) of the first link 151 and the first hinge shaft is the first end of the first link and the bottom end (ground end) of the first ladder From 1/6 to 1/4 of the distance, this ratio is suitable for reasonable load.

Further, the first vertical side 111 of the first ladder, the first link 151 and the first lateral support rod 13 form a triangle, and the first vertical of the first ladder The angle between the edge 111 and the first link 151 is at most 120 degrees, which can satisfy a large adjustment range and a reasonable force angle.

Further, when the angle between the first vertical side of the first ladder and the first link is at most 120 degrees, the angle between the first link and the first lateral support bar is At 60 degrees, the angle between the first vertical side of the first ladder and the first lateral support rod is 60 degrees, so that the force distribution is reasonable.

Further, the maximum angle between the first ladder 11 and the second ladder 12 is 60 degrees. Therefore, the angle between the first ladder and the second ladder is 60 degrees, the angle between the first link and the first lateral support bar is 60 degrees, and the first vertical side of the first ladder And the angle of the first lateral support bar is 60 degrees, that is, the tetrahedron formed by the first link, the first lateral support bar, the first ladder and the second ladder has multiple At an angle of 60 degrees, a plurality of equilateral and equiangular tetrahedrons are formed, so that the entire ladder has the most stable structure in mechanical properties.

Further, the rotation range of the first lateral support rod 13 is hemispherical, and the first lateral support rod 13 is located outside the rectangular space or the ladder-shaped space formed by the first ladder 11 and the second ladder 12, The two lateral support bars 14 are also located outside the rectangular space or the ladder-shaped space formed by the first and

second ladders

11 and 11, and the first lateral support bars 13 and the second lateral support bars 14 may be located in the first piece. The intermediate position of the ladder 11 and the second ladder 12 may also be located at a non-intermediate position of the first ladder 11 and the second ladder 12, and may be adjusted according to actual application conditions.

The invention increases the stability of the two lateral support bars, increases the stability and strength of the internal connection between the two lateral support bars and the two hinged ladders, and in turn, the two sides through the two locking devices The support rod and the ladder main body, that is, the two hinged ladders are locked, thereby avoiding the two lateral support rods from being loosely opened during use, thereby reducing safety hazards.

Further, the first lateral support rod and/or the second lateral support rod is a telescopic rod, and the telescopic rod includes at least: a first joint rod 131 and a second joint rod 132 connected to each other, the first The first rod and the second rod are respectively provided with a plurality of different height connecting holes, and the connecting holes are provided with positioning pins or positioning screws, the first Positioning rod and second rod positioning pin or positioning screw positioning connection;

The first node bar 131 and the second node bar are rectangular rods; or as shown in FIG. 2, the first node bar and the second node bar have a rectangular cross section, and the first node of the telescopic rod The second section rod can be integrally formed of aluminum alloy or formed of other metal materials.

The above is only the exemplary embodiments of the present invention and is not intended to limit the scope of the present invention. The components of the present invention can be combined with each other without conflict, and any equivalent changes and modifications made by those skilled in the art without departing from the spirit and scope of the present invention should be protected by the present invention. The scope. The above is only the exemplary embodiments of the present invention and is not intended to limit the scope of the present invention. The components of the present invention can be combined with each other without conflict, and any equivalent changes and modifications made by those skilled in the art without departing from the spirit and scope of the present invention should be protected by the present invention. The scope.

Claims

A folding ladder, characterized in that the folding ladder comprises: two hinged ladders, respectively a first ladder and a second ladder, and a ladder joint for articulating the first ladder and the second ladder The ladder joint includes:

a first locking tooth fixedly connected to the first ladder;

a second locking tooth connected to the second ladder;

The first ladder and the second ladder are rotatably connected by the first hinge shaft;

The first locking teeth and the second locking teeth mesh with each other, and the first locking teeth and the second locking teeth are one-way locking.
The folding ladder according to claim 1, wherein the first locking tooth is a semi-ring gear, the axis of the semi-ring gear is concentric with the first hinge shaft, and the second locking tooth Having a first end of the second locking tooth and a second end of the second locking tooth, the second locking tooth further has an inner side and an outer side, and the second locking tooth One end is hingedly connected to the second ladder through a second hinge shaft, the semi-ring gear is located between the first hinge shaft and the second hinge shaft; and the second end of the second locking tooth is abutted Pressing a reed spring, the inner side of the second locking tooth has a circular arc shape, and the inner side of the second locking tooth is provided with an engaging tooth that meshes with the semi-annular gear, the column The spring is pressed against the outer side surface at the second end of the second locking tooth.
The folding ladder according to claim 2, wherein the ladder joint further comprises: a first outer casing wrapped around the first locking teeth, and a second locking tooth wrapped around the second locking tooth a second outer casing, the first outer casing and the second outer casing being hinged by the first hinge shaft;

The first locking tooth is fixedly connected to the first outer box, and the second locking tooth is hingedly connected to the second outer box by the second hinge shaft; the first locking tooth Securely connecting with the first ladder by the first outer casing; the second locking tooth is connected to the second ladder by the rotational connection on the second outer casing, the second outer casing There is also a spring seat that supports the column spring.
The folding ladder according to claim 2, wherein said second hinge shaft is provided with a torsion spring for returning said second locking teeth.
The folding ladder according to claim 3, wherein said first outer casing has a first end of the first outer casing and a second end of the first outer casing, and said second outer casing has a second outer casing a first end and a second end of the second outer casing, the first end of the first outer casing being hinged to the first end of the second outer casing; the second end of the first outer casing being connected to the first end a ladder, the second end of the second outer casing is fixedly connected to the second ladder;

The ladder joint further includes: a pull wire connecting the second end of the second locking tooth, the pull wire being located in the second outer box, and extending from the second end of the second outer box to the On the outer surface of the second ladder.
The folding ladder of claim 5 wherein said pull wire is coupled to said second end of said second locking tooth in said post spring.
A folding ladder according to claim 5, wherein said second outer casing is further provided with guiding means for guiding said wire.
The folding ladder according to claim 5, wherein the first outer casing and the second outer casing are both upper and lower split structures.
The folding ladder according to claim 1, wherein the folding ladder further comprises: lateral support bars respectively disposed on two sides of the two ladders, wherein the lateral support bars are respectively disposed on the two ladders a first lateral support bar on one side and a second lateral support bar disposed on the second side of the two ladders.
The folding ladder of claim 9 wherein said folding ladder further comprises:

a first link movably coupled between the first ladder and the first lateral support bar;

a second link movably coupled between the second ladder and the first lateral support bar;

Locking the first locking device of the first link and the second link, connecting the first link and the second link;

The first locking device is disposed on the first lateral support rod.
The folding ladder according to claim 10, wherein said first link has two ends, respectively being a first end of the first link and a second end of the first link, said first link The first end is fixedly connected to the first ladder, the second end of the first link is slidably coupled to the first lateral support rod; the second link has two ends, respectively a first end of the second link and a second end of the first link, the first end of the second link is fixedly coupled to the second ladder, and the second end of the second link is slidable Attached to the first lateral support rod; the first locking device is slidably disposed on the first lateral support rod, and the first locking device simultaneously connects the first link and the second link.
The folding ladder of claim 11 wherein said first locking means comprises:

a first locking sleeve is sleeved on the first lateral support rod, the first locking sleeve is an annular ring having an opening, and the first locking sleeve has a first locking sleeve first end and a first locking sleeve a locking sleeve second end; the opening is disposed between the first end of the first locking sleeve and the second end of the first locking sleeve;

An adjusting bolt for controlling the size of the opening, extending through the opening, and connected between the first end of the first locking sleeve and the second end of the first locking sleeve; the length direction of the adjusting bolt is perpendicular to the first One side of the support rod in the longitudinal direction; the first end of the adjusting bolt is a nut, and the end end of the adjusting bolt is a screw end;

a hinge shaft of the locking device is disposed at a tail end of the adjusting bolt, wherein a length direction of the hinge shaft is perpendicular to a length direction of the adjusting bolt and parallel to a length direction of the first lateral support rod;

An eccentric cam hinged on the hinge shaft of the locking device and an outer edge of the eccentric cam is pressed against an outer side surface of the second end of the first locking sleeve;

a handle connecting the eccentric cam;

A locking return spring is sleeved on the adjusting bolt and located between the first end of the first locking sleeve and the second end of the first locking sleeve.
The folding ladder according to claim 12, wherein said first ladder and said second ladder are hingedly connected by a first hinge, said first ladder comprising: a first vertical side and a second vertical side And a plurality of lateral sides connected between the first vertical side and the second vertical side, the first end of the first link is fixedly connected to the first vertical side of the first ladder, The distance between the first end of the first link and the first hinge axis is 1/8 to 1/2 of the distance between the first end of the first link and the bottom end of the first ladder.
The folding ladder according to claim 13, wherein the first vertical side of the first ladder, the first link, and the first lateral support bar form a triangle, wherein the triangle The angle between the first vertical side of the first ladder and the first link is at most 120 degrees.
The folding ladder according to claim 14, wherein the first link and the seat are at an angle of at most 120 degrees between a first vertical side of the first ladder and the first link The angle of the first lateral support rod is 60 degrees, and the angle between the first vertical side of the first ladder and the first lateral support rod is 60 degrees.
The folding ladder of claim 1 wherein said first and second ladders have a maximum angle of 60 degrees.
The folding ladder of claim 9 wherein said first lateral support rod has a hemispherical extent of rotation.
The folding ladder according to claim 11, wherein the inner wall of the first locking sleeve is rectangular having an opening, and the outer side of the first lateral supporting rod is rectangular.