WO2018040122A1 - New extension ladder - Google Patents

Abstract

Disclosed is a new extension ladder, comprising at least three ladder sections. The ladder sections comprise ladder leg tubes (1) and ladder rungs (2). Both ends of each ladder rung (2) are connected to a ladder rung support (3), the ladder rung supports (3) being connected to the ladder leg tubes (1); of the ladder sections vertically adjacent to each other, the upper ladder leg tubes (1) insert into the lower ladder leg tubes (1). The new extension ladder further comprises a tension snap ring lowering apparatus. The tension snap ring lowering apparatus comprises a tension snap ring (14) and a tension snap ring support (11), wherein a fastening hole (12) is provided above the tension snap ring support (11); an annular groove is provided at the lower end of the tension snap ring support (11); the tension snap ring (14) is seated within the annular groove; a fastening position is provided at the lower end of the inner wall of the upper ladder leg tube (1), said fastening position matching the fastening hole (12); and the tension snap ring (14) sits in tight contact with the inner wall of the adjacently lower ladder leg tubes tube (1). The new extension ladder is convenient to operate and is safer, and the connection between the ladder rungs is secure.

Description

New extension ladder Technical field

The invention relates to a ladder, in particular to an extension ladder.

Background technique

Ladders are a necessity in people's daily life and engineering work. Ladders are usually long and bulky, so there are many inconveniences in handling and storage. For this reason, some manufacturers have designed retractable ladders to solve the above problems. Among the more representative types of telescopic ladders, the problem of inconvenience in the handling and storage of the ladder is solved. However, in actual use, the shrinkage and deployment process takes a long time, and the descending speed of the ladder is easy to hurt. The connection between the person and the step is not strong enough.

Summary of the invention

In order to overcome the shortcomings of the existing expansion and contraction process of the existing extension ladder, the speed of the descending speed of the step is easy to hurt, and the connection between the steps is not strong, the invention provides a convenient operation, high safety, and step between the steps. A new type of extension ladder with good connection.

The technical solution adopted by the present invention to solve the technical problem thereof is:

A new type of telescopic ladder includes at least three steps, the step includes a ladder column tube and a step, both ends of the step are connected with the step bracket, and the step bracket is connected with the ladder column tube, Among the upper and lower adjacent steps, the upper ladder tube is nested in the adjacent lower ladder tube, and the new extension ladder further includes a tension opening ring descending device, and the tension opening ring descending device includes a tension opening ring. And a tensioning ring ring bracket, wherein the tensioning ring ring bracket is provided with a fixing button hole, and the lower end of the tensioning ring ring bracket is provided with an annular groove, and the tension groove is set in the annular groove, and the ladder is located above The lower end of the inner wall of the column tube a fastening position, the buckle is engaged with the fixing buckle hole, and the tension opening ring is closely attached to an inner wall of the adjacent lower ladder tube;

The outer diameter of the tension ring bracket is larger than the inner diameter of the ladder tube above, and the outer diameter of the tension ring in the natural state is larger than the inner diameter of the adjacent lower column tube.

Further, a soft body buffer device is disposed on the step bracket, and the software buffer device has an outer convex shape.

Further, the ladder column tube is provided with an inner fixing column hole, and the step bracket is provided with an outer fixing column hole, and the fixing column passes through the outer fixing column hole and the inner fixing column hole, and the fixing column is opened There is a pin hole through which the fixed post latch passes through the stepped bracket.

Further, in addition to the topmost and bottommost steps, a triangular swing arm unlocking device is installed in the step bracket of each of the steps, and the triangular swing arm unlocking device includes a hand push switch, an unlocking boss, a triangular swing arm, a cylinder, a spring and a positioning pin, the hand push switch is interlocked with the positioning pin, one end of the positioning pin is in contact with one end of the spring, and the other end of the spring is located in the cylinder, and the cylinder is fixed in the step bracket The other end of the positioning pin cooperates with the positioning hole of the ladder column tube, and the middle portion of the positioning pin is linked with the first action end of the triangular swing arm, and the second action end of the triangular swing arm and the adjacent lower triangular swing arm The boss of the unlocking device cooperates.

The beneficial effects of the invention are mainly manifested in the following: the operation is convenient, the shrinking and unfolding process takes a short time, the safety is high, and the connection between the steps is firm.

DRAWINGS

Fig. 1 is a schematic view showing the construction of a new type of extension ladder in an extended state of use.

2 is a schematic structural view of a step positioning locking device and a triangular swing arm unlocking device.

Figure 3 is a schematic view showing the structure of the tension opening ring descending device, wherein (a) is an exploded view of the tensioned ring ring bracket and the ladder tube located above; (b) the tension after assembly is opened. The structural drawing of the mouth loop descending device; (c) is a schematic view of the tension opening ring.

4 is a schematic view showing the configuration of the soft body cushioning device, in which (a) is in an unfolded state; and (b) is in a collapsed state.

Fig. 5 is a schematic view showing the construction of a step bracket fixing device.

Fig. 6 is a cross-sectional view taken along line A of Fig. 5, wherein (a) is a plan sectional view and (b) is a three-dimensional sectional view.

detailed description

The invention is further described below in conjunction with the drawings.

Referring to FIGS. 1-6, a new type of extension ladder includes at least three steps, the step includes a ladder column tube 1 and a step 2, and both ends of the step 2 are connected with the step bracket 3, the step The bracket 3 is connected to the ladder column tube 1. Among the upper and lower adjacent step segments, the upper ladder column tube is nested in the adjacent lower ladder column tube, and the new extension ladder further includes a tension opening ring descending device. The tension opening ring descent device includes a tension split ring 14 and a tension split ring bracket 11 . The tension split ring bracket 11 is provided with a fixing buckle hole 12 , and the lower end of the tension split ring bracket 11 is provided with an annular groove. The tension slot is disposed in the annular groove, and a buckle is disposed at a lower end of the inner wall of the ladder tube at the upper side, and the buckle is matched with the fixed buckle hole 12, and the tension opening ring 14 is closely adjacent to the adjacent The inner wall of the ladder tube below;

The outer diameter of the tension split ring bracket 11 is larger than the inner diameter of the ladder tube 1 above, and the outer diameter of the tension split ring 14 in the natural state is larger than the inner diameter of the adjacent lower ladder tube 1.

Further, a soft buffer device 15 is disposed on the step bracket 3, and the software buffer device 15 has an outer convex shape.

Further, the ladder column tube 1 is provided with an inner fixing column hole 19, and the step bracket is provided with an outer fixing column hole 18 through which the fixing column 16 passes through the outer fixing column hole 18 and the inner fixing column hole 19, the fixing post 16 is provided with a pin hole, and the fixing post pin 17 passes through the pin hole through the step bracket.

Further, in addition to the topmost and bottommost steps, a triangular swing arm unlocking device is installed in the step bracket of each of the other steps, and the triangular swing arm unlocking device includes a hand push switch 8, an unlocking boss 9, and a triangular pendulum The arm 10, the cylinder 4, the spring 5 and the positioning pin 6, the hand push switch 8 is interlocked with the positioning pin 6, one end of the positioning pin 6 is in contact with one end of the spring 5, and the other end of the spring 5 is located in the cylinder 4. The cylinder 4 is fixed in the step bracket 3, and the other end of the positioning pin 6 is engaged with the positioning hole of the ladder tube 1. The middle portion of the positioning pin 6 is linked with the first action end of the triangular swing arm 10, The second action end of the triangular swing arm 10 cooperates with the boss of the adjacent lower triangular swing arm unlocking device.

Referring to FIG. 2, the triangular swing arm unlocking device is installed at each end of the other step 2 except the bottom step 2 (1) and the top step 2 (n), and each set of positioning locking device includes a horizontally arranged circle. The cylinder 4, one end of the cylinder 4 is provided with a spring 5, the other end of the cylinder 4 is provided with a positioning pin 6, and the triangular swing arm unlocking device further comprises a hand push unlocking switch 8 installed at both ends of the step 2 (2), unlocking The boss 9 and the triangular swing arm 10. When the ladder is stretched apart, when the step rises until the positioning pin 6 corresponds to the circular hole 7 on the ladder tube 1, the positioning pin 6 is automatically inserted into the circular hole 7 by the action of the spring 5, thereby locking the step. Do not drop, continue to stretch until the following steps are all open, you can use. When the ladder needs to be contracted, the push switch 8 at both ends of the step 2 is pushed in the direction indicated by the arrow to drive the positioning pin 6 (1) to move in the same direction and exit from the positioning hole 7 (1) of the ladder tube 1 (2). The upper step is then dropped. When the previous step is lowered onto the step 2, the unlocking boss on the step 2 is pressed upward by a stepped triangular swing arm 10, and the triangular swing arm 10 will rotate along its own axis of rotation and drive The positioning pin 6 (2) moves in the direction indicated by the arrow and exits from the positioning hole 7 (2) of the ladder column 1 (3), and the above step is lowered. Drop, and so on, until the entire ladder is contracted.

Referring to FIG. 3, a tension opening ring descending device is provided at the bottom end of all the ladder tube except the bottommost ladder tube, including a tension opening ring bracket 11, a fixed button hole 12, and a buckle on the ladder column tube. 13. Tension opening ring 14. The upper end of the tensioning ring ring bracket is provided with a plurality of fixing button holes for fastening to the buckles processed at the lower end of the ladder column tube. The lower end of the tension opening ring bracket is provided with a slot for installing the tension opening ring and the tension opening ring. When it is not installed in the ladder column tube, its diameter is larger than the inner diameter of the ladder column tube. After being installed in the ladder column tube, it will adhere to the inner wall of the ladder column tube by its own tension, thereby increasing the frictional force. When the step is lowered, the step will slowly drop under the action of friction.

Referring to Figure 4, in the upper half of the ladder there are a number of soft, soft cushioning devices 15 disposed on the step bracket. If the ladder is accidentally dumped, it can avoid the direct impact of important structural parts (such as ladder tube, step, step bracket, etc.) in the upper part of the ladder with the ground, transfer the force point, and because the dumping impact buffer is a soft part, Effectively reduce the impact of the ladder dumping, thus effectively protecting the ladder to maintain normal function after dumping and to meet the mechanical properties of normal use.

Referring to FIG. 5 and FIG. 6 , the step bracket fixing device mainly includes: a fixing post 16 , a fixing post latch 17 , an outer fixing post hole 18 , and an inner fixing post hole 19 . On the step bracket and the ladder column tube, there are an outer fixing column hole 18 and an inner fixing column hole 19 which are provided for the fixing column 16, and the fixing column 16 is inserted into the outer fixing column hole 18 and the inner fixing column hole 19, and the shaft of the step bracket is Inserting the fixing post latch 17 and fixing the fixing post 16 in the outer fixing post hole 18 on the step bracket, so that the step bracket is fastened on the ladder post tube without being pulled out, thereby ensuring the safety and stability of the ladder.

It is apparent that the above-described examples of the present invention are merely illustrative of the present invention and are not intended to limit the embodiments of the present invention. For the field Other variations or modifications of the various forms may be made by those of ordinary skill in the art. It is not possible to exhaust all implementations here. Obvious changes or variations which are obvious to those skilled in the art are still within the scope of the invention.

Claims (4)

A new type of telescopic ladder includes at least three steps, the step includes a ladder column tube and a step, both ends of the step are connected with the step bracket, and the step bracket is connected with the ladder column tube, Among the upper and lower adjacent steps, the upper ladder column tube is nested in the adjacent lower ladder column tube, wherein the new extension ladder further includes a tension opening ring descending device, and the tension opening ring descending device The tension split ring and the tension split ring bracket are disposed above the tension split ring bracket, and the lower end of the tension split ring bracket is provided with an annular groove, and the tension slot is disposed in the annular groove. a buckle is disposed at a lower end of the inner wall of the upper ladder tube, the buckle is matched with the fixed buckle hole, and the tension opening ring is closely attached to an inner wall of the adjacent lower step tube; The outer diameter of the tension split ring bracket is larger than the inner diameter of the ladder tube located above, and the outer diameter of the tension split ring in the natural state is larger than the inner diameter of the adjacent lower step tube. The new type of extension ladder according to claim 1, wherein the step bracket is provided with a soft body buffering device, and the software cushioning device has an outer convex shape. The new type of telescopic ladder according to claim 1 or 2, wherein the ladder column tube is provided with an inner fixing column hole, and the step bracket is provided with an outer fixing column hole, and the fixing column passes through the outer fixing The column hole and the inner fixing column hole are provided with a pin hole, and the fixing column pin passes through the pin hole through the step bracket. The new type of telescopic ladder according to claim 1 or 2, wherein in addition to the topmost and bottommost step, a triangular swing arm unlocking device is installed in the step bracket of each of the steps, and the triangular swing arm is unlocked. The device comprises a hand push switch, an unlocking boss, a triangular swing arm, a cylinder, a spring and a positioning pin, wherein the hand push switch is linked with the positioning pin, one end of the positioning pin is in contact with one end of the spring, and the other end of the spring is located In the cylinder, the cylinder is fixed in the step bracket, and the other end of the positioning pin is matched with the positioning hole of the ladder column tube, and the positioning pin is The portion is interlocked with the first action end of the triangular swing arm, and the second action end of the triangular swing arm is engaged with the boss of the adjacent lower triangular swing arm unlocking device.

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