A portable folding ladder for supermarkets

Abstract

The application relates to the field of ladders, in particular to a portable folding ladder for supermarkets. The folding ladder comprises two parallel side plates, a plurality of groups of fixed folding pieces arranged in the vertical direction between the two side plates, and a movable folding piece arranged between the two side plates below the fixed folding pieces. The movable folding piece comprises two second steps, the opposite ends of the two second steps are hingedly connected, a pin shaft is fixed on the end of the second step facing the side plate, a movable block is rotatably connected on the pin shaft, the movable block is slidably connected with the side plate on one side, a gear is fixed on the pin shaft, the gear is meshed with a rack, the rack is slidably connected with the side plate on one side, a first driving piece for driving the movable block to move up and down is arranged in the side plate, and a second driving piece for driving the rack to move up and down is arranged in the side plate. When the folding ladder is not used, the fixed folding pieces and the movable folding piece can be folded to reduce the width of the folding ladder, the folding ladder is convenient to move, and the folding ladder occupies a small space when stored.

Description

Technical Field

[0001] This invention relates to a field, specifically to a portable folding ladder for supermarkets. Background Technology

[0002] When displaying goods on the upper shelves of supermarkets, some shelves are too high to easily place the goods, necessitating the use of ladders. Existing ladders, however, occupy a significant amount of space when not in use. Most supermarket ladders are folding ladders, consisting of two parts that unfold into an inverted V-shape. Salespeople use these unfolded ladders to place goods on the upper shelves. However, the width of these ladders remains constant after folding, making storage inconvenient. Some ladders offer adjustable widths, typically with extendable steps. By changing the length of the steps after folding, the overall width of the ladder can be altered. These adjustable-width ladders generally require a stable and reliable positioning device to ensure stability during operation. However, existing positioning devices are complex and difficult to operate, or require considerable force to stabilize the ladder after unfolding. Since most supermarket salespeople are female, existing adjustable-width ladders are inconvenient to use in supermarkets. Summary of the Invention

[0003] The technical problem to be solved by the present invention is a folding ladder for supermarkets that is easy to use, has good stability, and can reduce the overall width of the ladder when folded, making it convenient to carry and store.

[0004] To achieve the above objectives, the technical solution provided by this invention is as follows:

[0005] A portable supermarket folding ladder includes two parallel side panels. Multiple sets of fixed folding components are vertically arranged between the two side panels. A set of corresponding movable folding components is located between the two side panels below the fixed folding components. Each set of movable folding components includes two second pedals, hinged at their opposite ends. A pin is fixed to the end of each second pedal facing the side panel, and a movable block is rotatably connected to the pin. The movable block is slidably connected to one side panel. A gear is fixed to the pin, meshing with a rack. The rack is slidably connected to one side panel. A first driving component and a second driving component are respectively provided within the side panels to drive the movable block and rack up and down. The first and second driving components are connected to a driving device. The first and second driving components allow the movable block and rack to move upwards at a differential speed and then upwards at the same speed. During the differential upward movement of the movable block and rack, the upward speed of the rack is less than the upward speed of the movable block.

[0006] Specifically, the multiple fixed folding components are arranged at equal intervals in the vertical direction between the two side plates.

[0007] Specifically, each set of fixed folding components includes two first pedals, with the opposite ends of the two first pedals hinged together and connected by a torsion spring. A fixing block is hinged to the end of the first pedal facing the side plate, and the fixing block is fixedly connected to the side plate on one side. When the two first pedals are parallel and perpendicular to the side plate, the fixing block allows the first pedal to be limited. After the first pedal is subjected to force, the first pedal remains in a horizontal state.

[0008] Specifically, the two side plates are arranged symmetrically on the left and right, and the fixing blocks on the two side plates are staggered front and back, with limit grooves opened at the lower end of each fixing block.

[0009] Specifically, the opposite ends of the two second pedals are connected by a pivot hinge. When the two second pedals are parallel and perpendicular to the side plate, the movable block allows the second pedals to be limited. After the upper end of the second pedal is subjected to force, the second pedal remains in a horizontal state.

[0010] Specifically, the movable block is slidably disposed in the first groove on the side plate, and the rack is slidably disposed in the second groove on the side plate. The first and second grooves are parallel, and the length direction of the first groove is parallel to the length direction of the side plate. The first driving member is a first screw rotatably disposed in the side plate, which passes through the first groove and is threadedly connected to the movable block. The second driving member is a second screw rotatably disposed in the side plate, which passes through the second groove. The threads on both the first and second screws are single-start threads. The second screw passes through a through hole on the rack, and a fitting bolt is fixed at the lower end of the through hole. The fitting bolt is inserted into the thread groove of the second screw. The thread on the second screw is divided into two ends. The thread pitch of the lower section is smaller than that of the upper section, and the thread pitch of the upper section of the second screw is equal to that of the first screw.

[0011] Specifically, the driving device includes a motor fixed inside the lower end of the side plate, the output shaft of the motor is connected to the first screw, and the output shaft of the motor is connected to the lower end of the second screw via a transmission belt.

[0012] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0013] 1. This invention features a fixed folding component and a movable folding component. When not in use, the fixed and movable folding components can be folded to reduce the width of the folding ladder, making it easy to move and requiring little space when stored.

[0014] 2. The fixed and movable folding parts can be folded and unfolded by starting the motor. This folding ladder saves time and effort during the folding process and is convenient to fold and unfold. The folding ladder has good stability after unfolding. Attached Figure Description

[0015] Figure 1 This is a three-dimensional view of the present invention.

[0016] Figure 2 This is a schematic diagram showing the connection between the fixed folding component and the movable folding component and the side panel.

[0017] Figure 3 for Figure 2 A magnified view of region A in the middle.

[0018] Figure 4 This is a schematic diagram of the movable folding component.

[0019] Figure 5 This is a front view of the fixed folding component.

[0020] Figure 6 This is a rear view of the fixed folding component.

[0021] Figure 7 This is a top view of the rack.

[0022] Figure 8 This is a comparison diagram of the pitch of the second screw thread inside the through hole and the pitch of the first screw thread.

[0023] The names of the components in the attached diagram are:

[0024] 1. Side plate; 2. First pedal; 3. Fixing block; 4. Limiting groove; 5. Second pedal; 6. Movable block; 7. Gear; 8. Rack; 9. Motor; 10. First screw; 11. First slide groove; 12. Transmission belt; 13. Second screw; 14. Fitting bolt; 15. Second slide groove; 16. Through hole. Detailed Implementation

[0025] like Figure 1 As shown, a portable supermarket folding ladder includes two parallel side panels 1, symmetrically arranged left and right. Multiple sets of fixed folding members are arranged vertically between the two side panels 1. Multiple sets of movable folding members are also arranged vertically between the two side panels 1. Each movable folding member corresponds to a fixed folding member. The multiple fixed folding members are arranged at equal intervals in the vertical direction between the two side panels 1.

[0026] like Figure 2 , Figure 3 and Figure 4As shown, each set of movable folding components includes two second pedals 5. The opposite ends of the two second pedals 5 are hinged together. A pin is fixed to the end of the second pedal 5 facing the side plate 1, and a movable block 6 is rotatably connected to the pin. The movable block 6 is slidably connected to the side plate 1 on one side. A gear 7 is fixed to the pin, and the gear 7 meshes with a rack 8. The rack 8 is slidably connected to the side plate 1 on one side. A first driving member and a second driving member are respectively provided in the side plate 1 to drive the movable block 6 and the rack 8 to move up and down. The first driving member and the second driving member are connected to a driving device. The first driving member and the second driving member allow the movable block 6 and the rack 8 to move up at a differential speed and then up at the same speed. During the differential upward movement of the movable block 6 and the rack 8, the upward speed of the rack 8 is less than the upward speed of the movable block 6.

[0027] like Figure 1 , Figure 5 and Figure 6 As shown, each set of fixed folding components includes two first pedals 2. The opposite ends of the two first pedals 2 are hinged together. The opposite ends of the two first pedals 2 are connected by a torsion spring. The torsion spring is sleeved on the hinge shaft between the two first pedals 2, and the two ends of the torsion spring are respectively fixed to the two first pedals 2. A fixing block 3 is hinged to the end of the first pedal 2 facing the side plate 1, and the fixing block 3 is fixedly connected to the side plate 1 on one side. The fixing blocks 3 on the two side plates 1 are staggered. A limiting groove 4 is opened at the lower end of each fixing block 3. When the two first pedals 2 are parallel and perpendicular to the side plate 1, the fixing block 3 allows the first pedal 2 to be limited, so that the first pedal 2 remains in a horizontal state after being subjected to force at the upper end.

[0028] like Figure 1 and Figure 4 As shown, the opposite ends of the two second pedals 5 are connected by a pivot hinge. When the two second pedals 5 are parallel and perpendicular to the side plate 1, the movable block 6 is stably located at the lower limit of its allowable range of motion. The movable block 6 allows the second pedals 5 to be limited, and after the upper end of the second pedals 5 is subjected to force, the second pedals 5 are kept in a horizontal state.

[0029] like Figure 2 , Figure 3 , Figure 7 and Figure 8As shown, the movable block 6 is slidably disposed within the first groove 11 on the side plate 1. The rack 8 is slidably disposed within the second groove 15 on the side plate 1. The first groove 11 and the second groove 15 are parallel, and the length direction of the first groove 11 is parallel to the length direction of the side plate 1. The first driving member is a first screw 10 rotatably disposed within the side plate 1, which passes through the first groove 11 and is threadedly connected to the movable block 6. The second driving member is a second screw 13 rotatably disposed within the side plate 1, which passes through the second groove 15. The threads on both the first screw 10 and the second screw 13 are single-start threads. The second screw 13 passes through a through hole 16 on the rack 8, and a fitting bolt 14 is fixed at its lower end within the through hole 16. The fitting bolt 14 is inserted into the threaded groove of the second screw 13. The thread on the second screw 13 is divided into two ends, with the thread pitch of the lower section being smaller than that of the upper section. The thread pitch of the upper section of the second screw 13 is equal to that of the first screw 10.

[0030] like Figure 1 , Figure 2 and Figure 3 As shown, the driving device includes a motor 9 fixed in the lower end of the side plate 1. The output shaft of the motor 9 is connected to the first screw 10, and the output shaft of the motor 9 is connected to the lower end of the second screw 13 via a transmission belt 12.

[0031] Figure 1 The diagram shows the state of this folding ladder in use. When the ladder needs to be folded, the motor 9 is started, causing the first screw 10 and the second screw 13 to rotate at the same speed and in the same direction. Because the thread pitch of the second screw 13 inside the through hole 16 is less than the thread pitch of the first screw 10, the lead of the threaded portion of the second screw 13 inside the through hole 16 is less than the lead of the thread on the first screw 10. That is, after the first screw 10 and the second screw 13 rotate one revolution simultaneously, the upward distance of the movable block 6 is greater than the upward distance of the rack 8. During the rotation of the first screw 10 and the second screw 13 at the same speed and in the same direction, a speed difference will occur between the upward movable block 6 and the rack 8, with the upward speed of the movable block 6 being greater than that of the rack 8. Due to this speed difference, the rack 8 and the gear 7 will move relative to each other. During the differential upward movement of the movable block 6 and the rack 8, the gear 7 will drive the second pedal 5 to rotate upward. During the upward rotation of the second pedal 5 driven by the gear 7, the opposite ends of the two first pedals 2 will rotate upward under the elastic force of the torsion spring, and the two side plates 1 will move closer to each other.

[0032] As the two side plates 1 approach each other, the folding of the side plates 1 is completed when the fixing block 3 contacts the side plates 1 simultaneously. At this time, the thread pitch of the mating bolt 14 in the through hole 16 and the thread pitch of the second screw 13 are equal to the thread pitch of the first screw 10. Then, as the first screw 10 and the second screw 13 rotate at the same speed and in the same direction, the movable block 6 and the rack 8 move upward at the same speed. The rack 8 and the gear 7 will not move relative to each other, and the swing of the second pedal 5 ends. When the fixing block 3 contacts the two side plates 1 simultaneously, the two fixing blocks 3 overlap. At this time, the limiting grooves 4 at the lower ends of the two overlapping fixing blocks 3 form a rectangular groove. As the movable block 6 and the rack 8 move upward at the same speed, when the hinged ends of the two second pedals 5 enter the rectangular groove formed by the two limiting grooves 4, the motor 9 can stop moving. After the motor 9 is turned off, the hinged ends of the two second pedals 5 are engaged in a rectangular groove formed by two limiting grooves 4. Under the limiting effect of the rectangular groove on the two second pedals 5, the two second pedals 5 can be prevented from rotating and unfolding. Therefore, the two side panels 1 will not move away from each other, and this folding ladder is convenient to store after folding.

[0033] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A portable supermarket folding ladder comprising two side plates (1) arranged in parallel, characterized in that, A plurality of sets of fixed folding pieces are arranged in the vertical direction between the two side plates (1), and a corresponding set of movable folding pieces is arranged between the two side plates (1) below the fixed folding pieces. Each set of movable folding pieces comprises two second pedals (5), the opposite ends of the two second pedals (5) are hingedly connected, a pin shaft is fixed on one end of the second pedal (5) facing the side plate (1), a movable block (6) is rotatably connected to the pin shaft, the movable block (6) is slidingly connected to the side plate (1) on one side thereof, a gear (7) is fixed on the pin shaft, the gear (7) is engaged with a rack (8), the rack (8) is slidingly connected to the side plate (1) on one side thereof, a first driving member and a second driving member are arranged in the side plate (1) to drive the movable block (6) and the rack (8) to move up and down, the first driving member and the second driving member are connected to a driving device, the first driving member and the second driving member allow the movable block (6) and the rack (8) to move up at different speeds and then move up at the same speed, and the upstroke speed of the rack (8) is less than the upstroke speed of the movable block (6) during the differential upstroke of the movable block (6) and the rack (8); Each set of fixed folding pieces comprises two first pedals (2), the opposite ends of the two first pedals (2) are hingedly connected; a fixed block (3) is hingedly connected to one end of the first pedal (2) facing the side plate (1), and the fixed block (3) is fixedly connected to the side plate (1) on one side thereof; The two side plates (1) are arranged symmetrically left and right, and the fixed blocks (3) on the two side plates (1) are arranged staggered front and back, and a limiting groove (4) is formed at the lower end of each fixed block (3); With the upward movement of the movable block (6) and the rack (8) at the same speed, the hingedly connected ends of the two second pedals (5) enter and are clamped into the rectangular groove formed by the two limiting grooves (4).

2. The portable folding step ladder for use in a supermarket according to claim 1, wherein The plurality of sets of fixed folding pieces are arranged equidistantly in the up-down direction between the two side plates (1).

3. The portable folding step ladder for use in a supermarket according to claim 1, wherein The opposite ends of the two first pedals (2) are connected by a torsion spring, when the two first pedals (2) are parallel and perpendicular to the side plate (1), the fixed block (3) allows the first pedal (2) to be limited, and after the upper end of the first pedal (2) is stressed, the first pedal (2) remains in a horizontal state.

4. The portable folding step ladder of claim 1, wherein, The opposite ends of the two second pedals (5) are hingedly connected by a rotating shaft, when the two second pedals (5) are parallel and perpendicular to the side plate (1), the movable block (6) allows the second pedal (5) to be limited, and after the upper end of the second pedal (5) is stressed, the second pedal (5) remains in a horizontal state.

5. The portable folding step ladder of claim 1, wherein, The movable block (6) is slidingly arranged in a first sliding groove (11) on the side plate (1), the rack (8) is slidingly arranged in a second sliding groove (15) on the side plate (1), the first sliding groove (11) and the second sliding groove (15) are parallel, the length direction of the first sliding groove (11) is parallel to the length direction of the side plate (1), the first driving member is a first screw rod (10) rotatably arranged in the side plate (1), the first screw rod (10) penetrates the first sliding groove (11) and is threadedly connected with the movable block (6), the second driving member is a second screw rod (13) rotatably arranged in the side plate (1), the second screw rod (13) penetrates the second sliding groove (15), the threads on the first screw rod (10) and the second screw rod (13) are single-threaded threads, the second screw rod (13) penetrates a through hole (16) on the rack (8), a matching bolt (14) is fixedly arranged in the through hole (16) at a lower end, the matching bolt (14) is inserted into a thread groove of the second screw rod (13), the threads on the second screw rod (13) are divided into two ends, the thread pitch of the lower section is smaller than the thread pitch of the upper section, and the thread pitch of the upper section of the second screw rod (13) is equal to the thread pitch of the first screw rod (10).

6. The portable supermarket folding ladder according to claim 5, wherein, The driving device comprises a motor (9) fixedly arranged in the lower end of the side plate (1), the output shaft of the motor (9) is connected with the first screw rod (10), and the output shaft of the motor (9) is connected with the lower end of the second screw rod (13) through a transmission belt (12).

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