Ladder with top platform

Abstract

To provide a ladder with a top plate that is easy to transport and store.SOLUTION: A ladder includes a pair of left and right support pillars 2 extending vertically and arranged side by side at a predetermined interval in the left-right direction, multiple steps 3 arranged horizontally between the support pillars 2, a top plate 4 arranged horizontally above the steps 3 between the support posts 2, a pair of left and right handrails 5 arranged along each support pillar 2, a handrail support part 9 that supports the handrails 5 so that they can be moved between an extended position where they are raised rearward of the rear surface section 2d of the support pillars 2 and a folded position where they are tilted toward the center between the support pillars 2, and a top-plate support part 8 that supports the top plate 4 so that it can be moved between an extended position where it extends forward of the support pillars 2 and a folded position where it is tilted forward and downward of the support pillars 2. The top plate 4 has a hook part 13 that can be hooked onto an installation target part P, and when in the folded position, it is arranged side by side with the support pillars 2 in the gap S1 between the two support pillars 2, and when the top-plate 4 is in the folded position, the hook part 13 is arranged rearward of a front surface part 2c of the support pillars 2.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a ladder with a top plate that is used by leaning it against a high place.

Background Art

[0002] In a ladder that is used by leaning it against a high place such as the upper part of a truck bed, in consideration of transportability and storage, a top plate provided at the upper part between the left and right support columns and handrails provided along each support column are each configured to be foldable (for example, Patent Document 1).

[0003] The ladder disclosed in Patent Document 1 includes a pair of left and right support columns, a plurality of treads horizontally installed between both support columns, a top plate horizontally installed between the upper end portions of both support columns, and a pair of left and right handrails provided along each support column. The top plate is displaceably connected to the upper end portion of the support column such that it can be fixed at the same angle as the treads in the use state and fixed at an angle that is in the same straight line so as to extend above the upper end of the support column in the non-use state. Further, hooks that can engage with the aori plates of the truck bed are provided on the left and right side surfaces of the top plate. The hooks are provided to protrude to the back side of the top plate. On the other hand, the handrails are displaceably connected to the shaft support portions arranged above and below the support column such that they can be displaced between a state of standing upright perpendicular to the support column and a state of being tilted parallel to the support column.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The ladder described in Patent Document 1 can be folded down to reduce its thickness in the front-to-back direction (directions perpendicular to the longitudinal direction of the support posts and rungs) when not in use by tilting the left and right handrails toward the center between the support posts and overlapping them, and by changing the angle of the top plate so that it extends above the upper end of the support posts.

[0006] However, even when folded as described above, the hooks on the top plate protrude forward from the support columns, which prevents the thickness from being reduced. Furthermore, it can get caught on other objects or ladders when carrying or stacking, hindering work.

[0007] This invention was made in view of the above-mentioned problems, and aims to provide a ladder with a top plate that is excellent in terms of transportability and storage. [Means for solving the problem]

[0008] To solve the above problems, the ladder with a top plate of the present invention employs the following technical means.

[0009] The ladder with a top plate of the present invention comprises a pair of left and right support columns extending vertically and arranged side by side at a predetermined interval in the left-right direction, a plurality of rungs horizontally between the support columns, a top plate horizontally positioned above the rungs between the support columns, and a pair of left and right handrails provided along each of the support columns, wherein the ladder with a top plate comprises a handrail support portion that supports the handrails so as to be displaceable between an extended position where they are raised to the rear of the rear surface of the support columns and a folded position where they are tilted toward the center between the support columns, and a top plate support portion that supports the top plate so as to be displaceable between an extended position where they extend forward of the support columns and a folded position where they are tilted toward the front and downward of the support columns, the top plate has a hook portion that can be engaged with the installation target, and when in the folded position, is arranged horizontally with the support columns in the gap between the two support columns, and when the top plate is in the folded position, the hook portion is positioned in front of the support columns It is positioned behind the surface.

[0010] The hook portion may be positioned forward of the outer surface portion of the handrail facing the rear when both the handrail and the top plate are in the folded position.

[0011] The top plate may be positioned such that, when in the folded position, the tread surface is positioned behind the front portion of the support column.

[0012] The top plate has a locking pin slidably supported on its underside opposite to the footboard surface, and a biasing member that presses and biases the locking pin in one direction of sliding. The top plate support may have a support bracket fixed to the upper end of the support column, a support shaft that pivotally connects the top plate to the support bracket, a first pin insertion hole through the support bracket through which the locking pin is inserted when the top plate is in the unfolded position, a second pin insertion hole through the support bracket through which the locking pin is inserted when the top plate is in the folded position, and a locking piece provided on the upper edge of the support bracket that contacts the footboard surface of the top plate when the top plate is in the unfolded position. [Effects of the Invention]

[0013] According to the ladder with a top plate of the present invention, the overall thickness of the ladder in the folded state can be reduced, and the unevenness of the front and back of the ladder can be reduced, so transportability and storageability are greatly improved. [Brief explanation of the drawing]

[0014] [Figure 1] This is a rear perspective view of the ladder with a top platform in its extended state. [Figure 2] This is a side view of the ladder with a top plate in its extended state. [Figure 3] This is an overhead view of the ladder with a top platform in its extended state. [Figure 4] This is a downward perspective view of the area around the top panel in its unfolded state. [Figure 5] This is a lateral cross-sectional view of the area around the top panel in the unfolded state. [Figure 6] This is a rear perspective view of the ladder with a top platform in its folded state. [Figure 7] It is a side view of the folded state of the ladder with a top plate. [Figure 8] It is a top view of the folded state of the ladder with a top plate. [Figure 9] It is a front view of the folded state of the ladder with a top plate.

Mode for Carrying Out the Invention

[0015] Hereinafter, a ladder with a top plate according to an embodiment of the present invention will be described based on the drawings. Note that the embodiment described below is an example that embodies the present invention, and does not limit the configuration of the present invention with that specific example.

[0016] As shown in FIGS. 1 and 2, the ladder 1 with a top plate of the present embodiment (hereinafter, appropriately referred to as "ladder") is a ladder for truck lifting mainly used by leaning on the awning plate P of the truck bed. It includes a pair of left and right columns 2 extending in the vertical direction and arranged in parallel at a predetermined interval in the left and right directions, a plurality of treads 3 horizontally installed between the columns 2, a top plate 4 horizontally installed above the treads 3 between the columns 2, and a pair of left and right handrails 5 provided along each column 2.

[0017] In this embodiment, as shown in FIGS. 1 to 3, with the state where both the top plate 4 and the handrail 5 are deployed as the basic posture, the longitudinal direction of the column 2 in the deployed state (the directions of the arrows Z1 and Z2 in FIGS. 1 and 2) is the vertical direction, the short direction of the column 2 and the longitudinal direction of the tread 3 (the directions of the arrows Y1 and Y2 in FIGS. 1 and 3) is the left and right direction, and the direction orthogonal to the short direction of the column 2 and the longitudinal direction of the tread 3 (the directions of the arrows X1 and X2 in FIGS. 1 to 3) is the front and rear direction. Further, in the ladder 1 of the present embodiment, one surface in the front and rear direction is used as the lifting surface for the user. However, in the ladder 1, the side where the user ascends and descends (the side of the arrow X2 in FIGS. 1 to 3) is the rear, and the opposite side (the side of the arrow X1 in FIGS. 1 to 3) is the front.

[0018] As shown in FIGS. 1 and 4, the support column 2 is a groove-shaped frame body with a substantially rectangular U-shaped cross section extending in the vertical direction, and the forming surface of the groove portion is arranged facing the other support column 2. That is, the two support columns 2 on the left and right are arranged side by side at a distance in the horizontal direction with the forming surfaces of the groove portions facing each other. Therefore, the forming surface of the groove portion becomes the inner side surface 2a of the support column 2, and the surface on the opposite side of the groove portion becomes the outer side surface 2b of the support column 2. Also, the outer side surfaces of the front and rear end plates that define the groove portion respectively become the front surface portion 2c and the rear surface portion 2d of the support column 2.

[0019] As shown in FIGS. 1 and 2, telescopic legs 6 are provided at the lower end portions 2U of each support column 2. Also, as shown in FIG. 1, a first locking mechanism portion 7 capable of fixing the telescopic leg 6 at an arbitrary sliding position is provided at the lower end portion 2U of the support column 2. By sliding the telescopic leg 6 in the longitudinal direction and fixing it at an arbitrary position by the first locking mechanism portion 7, the ladder 1 can be adjusted to a desired height (vertical length).

[0020] As shown in FIGS. 1 to 9, a top plate support portion 8 that supports the top plate 4 so as to be displaceable between a deployed position (see FIGS. 1 to 3) in which the top plate 4 extends forward of the support column 2 and a folded position (see FIGS. 6 to 9) in which the top plate 4 is tilted downward in front of the support column 2 is provided at the upper end portion 2T of each support column 2. Also, a handrail support portion 9 that supports the handrail 5 so as to be displaceable between a deployed position (see FIGS. 1 to 3) in which the handrail 5 stands up behind the rear surface portion 2d of the support column 2 and a folded position (see FIGS. 6 to 9) in which the handrail 5 is tilted to the central side between the support columns 2 is provided at an intermediate position of each support column 2.

[0021] As shown in FIGS. 1 and 2, a plurality of tread bars 3 are arranged in parallel at equal intervals at an intermediate position between the upper and lower portions on the inner side surface 2a of the support column 2. As shown in FIG. 5, the tread bar 3 is a cylindrical body with a substantially trapezoidal cross section, and extends between the support columns 2 in a posture in which its long surface portion 3c faces forward and its short surface portion 3d faces rearward. The tread surface portion (upper surface portion) 3a of the tread bar 3 is formed to extend forward and upward from the upper edge of the short surface portion 3d to the upper edge of the long surface portion 3c, and becomes substantially horizontal when the upper end portion 2T of the support column 2 is tilted downward at a predetermined angle.

[0022] As shown in Figures 1 to 5, the top plate 4 has a roughly rectangular top plate body 11 that extends in the left-right direction, a pair of left and right top plate horizontal frames 12 that cover the left and right end faces of the top plate body 11, and a hook portion 13 that is connected to the front end face portion 11a of the top plate body 11 and can be engaged with the tailgate P which is the part to be installed. Also, as shown in Figures 4 and 5, the connection portion between the top plate 4 and the top plate support portion 8 has a second locking mechanism portion 14 that can fix the top plate 4 to the support column 2 at a predetermined angular position.

[0023] As shown in Figure 5, the thickness dimension H1 in the vertical direction of the top plate body 11 is set to be smaller than the width dimension D1 in the front-to-back direction of the support column 2. In addition, the extension width L1 of the top plate body 11 from the center of the support shaft 22 to the front end surface portion 11a is set to be smaller than the distance from the center of the support shaft 22 to the tread surface portion 3a of the uppermost step rail 3, that is, the vertical width L2 of the gap S1 between the upper ends 2T of both support columns 2.

[0024] As shown in Figures 1 to 4, the top panel horizontal frame 12 is a groove-shaped frame with a roughly rectangular U-shaped cross-section, and is attached and fixed to the left and right end faces of the top panel body 11 so as to cover it from the outside. As shown in Figure 3, the distance between the sides of the two top panel horizontal frames 12, that is, the width dimension W1 of the top panel 4 in the left-right direction, is set to be smaller than the left-right width W2 of the gap S1 between the upper ends 2T of the two support columns 2. Therefore, when the top panel 4 is in the folded position, it is positioned side by side with the two support columns 2 in the gap S1 (see Figures 8 and 9).

[0025] As shown in Figures 1 to 4, the hook portion 13 is a frame that is roughly rectangular in shape when viewed from the side, and a pair of them are provided on the front end surface portion 11a of the top plate body 11, near the left and right sides. Also, Figure 4 As shown in Figure 5, the hook portion 13 has a base plate portion 13a that extends forward from the front end surface portion 11a of the top plate body 11, and a pair of engaging end plates 13b and 13c that extend downward from the front and rear edges of the base plate portion 13a.

[0026] The base plate portion 13a is connected to the front end surface portion 11a of the top plate body 11 at a position lower than the foot plate surface portion 4A of the top plate 4. Therefore, when the top plate 4 is in the folded position, the hook portion 13 is positioned behind the front portion 2c of the support column 2 (see Figures 6 to 8).

[0027] The inner engaging end plate 13b at the base end of the hook portion 13 extends downward from the back surface 4B of the top plate body 11, opposite to the tread surface 4A. The outer engaging end plate 13c at the tip end of the hook portion 13 extends parallel to the front of the inner engaging end plate 13b. Therefore, when the top plate 4 is in the folded position, the engaging end plates 13b and 13c are positioned in front of the outer surface 5B of the handrail 5 facing the rear of the ladder 1, that is, in the space inside the handrail 5 (see Figures 6 and 8).

[0028] Furthermore, as long as the ladder 1 can be properly leaned against the tailgate P and held in place, the hook portion 13 may be provided at only one location on the front end surface 11a, at three or more locations on the front end surface 11a, or it may be formed in a long shape extending horizontally along the front end surface 11a. In addition, the hook portion 13 may be provided on the top plate side frame 12 as long as it does not interfere with the support column 2 when the top plate 4 is folded.

[0029] As shown in Figure 5, the distance from the center of the support shaft 22 of the top plate 4 to the outer surface of the outer engaging end plate 13c of the hook portion 13, that is, the protruding length L3 to the tip of the hook portion 13 of the top plate 4, is set to be smaller than the vertical width L2 of the gap S1. Therefore, when the top plate 4 is folded, the hook portion 13 is positioned above the uppermost step rail 3 (see Figures 6 and 9).

[0030] As shown in Figures 4 and 5, the second locking mechanism 14 consists of a locking pin 15, a pin bracket 16, a compression spring 17 as a biasing member, a first pin insertion hole 18, and a second pin insertion hole 19. The locking pin 15 is a roughly L-shaped shaft and is supported so as to be slidable in the left-right direction relative to the pin bracket 16. The pin bracket 16 is fixed to the back surface 4B of the top plate 4. The compression spring 17 is a compression spring that applies a pressing force to the locking pin 15 toward the left-right outward direction (one side of the sliding direction) of the top plate 4.

[0031] As shown in Figures 2, 4, 5, and 7, the top plate support portion 8 includes a support bracket 21 that is bent in a stepped shape when viewed from the front, a support shaft 22 that pivotally connects the top plate horizontal frame 12 to the support bracket 21, and a locking piece 23 that abuts against the foot plate surface portion 4A of the top plate 4 when the top plate 4 is in the unfolded position. Furthermore, a first pin insertion hole 18 and a second pin insertion hole 19 of the second locking mechanism portion 14 are provided through the support bracket 21 around the support shaft 22.

[0032] The first pin insertion hole 18 is located in front of the support shaft 22 in the support bracket 21, and the lock pin 15 is inserted through it when the top plate 4 is in the unfolded position. The second pin insertion hole 19 is located below the support shaft 22 in the support bracket 21, and the lock pin 15 is inserted through it when the top plate 4 is in the folded position. As shown in Figure 5, in this embodiment, the first pin insertion hole 18 is located in a position that allows the top plate 4 to be held in a substantially horizontal position when the top plate 4 extends parallel to the tread surface 3a of the rung 3, that is, when the upper end 2T of the support column 2 is tilted forward and downward at a predetermined angle. On the other hand, the second pin insertion hole 19 is located below the extension direction of the support column 2 of the support shaft 22, that is, in a position that allows the top plate 4 to be held side by side with both support columns 2 (see Figure 7).

[0033] As shown in Figures 1 to 3, the locking piece 23 is a tongue-shaped piece formed by bending inward in the left-right direction from the upper edge of the support bracket 21, and makes surface contact with the foot plate surface 4A of the top plate 4 from the upper side when the top plate 4 is in the unfolded position. As a result, the top plate 4 can be folded even higher than the unfolded position. Rotation in the opposite direction to the current position is prevented. In this way, the top plate 4 is held in the deployed position with rotation prevented by the locking pin 15 and the locking piece 23 (see Figure 5).

[0034] As shown in Figures 1 and 2, the handrail 5 is a frame formed by bending a roughly cylindrical tube into an oval ring shape, and is connected and supported to each support column 2 via handrail support parts 9 in an orientation with its longitudinal direction as the vertical direction. As shown in Figure 3, when the handrail 5 is extended, the surface on the central side between the left and right sides of the ladder 1 becomes the inner surface 5A, and the opposite surface becomes the outer surface 5B. Therefore, when folded, the inner surface 5A of the handrail 5 faces the rear surface 2d side (front) of the support column 2, and the outer surface 5B faces the rear of the ladder 1 (see Figure 8).

[0035] As shown in Figures 1 and 2, the handrail 5 has a pair of straight front handrail frames 31a and rear handrail frames 31b arranged parallel to each other, and a semi-circular upper handrail frame 31c and lower handrail frame 31d that connect the upper and lower ends of the front handrail frame 31a and rear handrail frame 31b.

[0036] The front handrail frame 31a is supported so as to be slidable vertically and rotatable circumferentially relative to the handrail support 9. In other words, the front handrail frame 31a serves as the pivot point when sliding or tilting the handrail 5. On the other hand, the rear handrail frame 31b and the upper handrail frame 31c serve as gripping points when ascending or descending the ladder 1.

[0037] A cylindrical upper stopper 32 and a lower stopper 33 are provided ring-shaped on the front frame 31a of the handrail, spaced at a predetermined interval in the vertical direction. The upper stopper 32 is fixed ring-shaped on the outer surface of the front frame 31a at a position closer to the upper frame 31c of the handrail, that is, at a position closer to the upper end of the front frame 31a. The lower stopper 33 is fixed ring-shaped on the outer surface of the front frame 31a at a position closer to the lower frame 31d of the handrail, that is, at a position closer to the lower end of the front frame 31a.

[0038] Furthermore, the front frame 31a of the handrail is provided with a lower pin insertion hole 34 and an upper pin insertion hole 35 through which the lock pin 44 of the third locking mechanism 43, which will be described later, can be inserted. The lower pin insertion hole 34 is located on the front frame 31a of the handrail near the lower frame 31d of the handrail and above the lower stopper 33, and is provided in the left-right direction. The upper pin insertion hole 35 is located on the front frame 31a of the handrail near the upper frame 31c of the handrail and below the upper stopper 32, and is provided in the front-back and left-right directions.

[0039] The rear handrail frame 31b is installed alongside the front handrail frame 31a at a predetermined distance. As shown in Figures 3 and 8, the distance between the outer edges of the front handrail frame 31a and the rear handrail frame 31b, i.e., the front-to-back width dimension D2 of the handrail 5, is set to be smaller than the distance between the outer edges of the front handrail frames 31a on both sides, i.e., half of the left-to-right outer width W3 between the two handrails 5. Therefore, when the two handrails 5 are in the folded position, they do not overlap in the front-to-back direction and are arranged side by side (see Figures 6, 8, and 9).

[0040] As shown in Figures 1 to 4, the handrail support section 9 includes a substantially cylindrical holder section 41 that is fitted around the handrail front frame 31a, a substantially rectangular cylindrical connecting frame section 42 that connects and supports the holder section 41 to each support column 2, and a third locking mechanism section 43 that can fix the handrail 5 to the support column 2 at a predetermined sliding position and angular position. The handrail front frame 31a is inserted and held inside the holder section 41 so as to be able to slide vertically and rotate in the circumferential direction. Furthermore, when the handrail 5 is slid upward along the holder section 41, the lower stopper 33 abuts against the lower end of the holder section 41, preventing the handrail 5 from sliding upward. That is, the handrail 5 is stopped at the upper position of the support column 2 (see Figure 2). Conversely, when the handrail 5 is slid downward along the holder section 41, the upper stopper 32 abuts against the upper end of the holder section 41, preventing the handrail 5 from sliding downward. In other words, the handrail 5 is stopped at a position below the support post 2 (see Figure 7).

[0041] The holder portion 41 extends vertically along the rear of the connecting frame portion 42. The connecting frame portion 42 is integrally formed with the holder portion 41 and is fixed to the outer surface portion 2b of the support column 2. In this way, the holder portion 41 supports the handrail 5 at the left and right outer rear corner portions of the support column 2.

[0042] As shown in Figure 4, the third locking mechanism 43 consists of a locking pin 44, a pin bracket 45, a compression spring 46, and a lower pin insertion hole 34 and an upper pin insertion hole 35 provided in the front frame 31a of the handrail. The locking pin 44 is a roughly rectangular U-shaped shaft, with one end inserted and held through the pin bracket 45 from the outside in the left-right direction, and the other end inserted through the holder portion 41 from the outside in the left-right direction. The pin bracket 45 is fixed to the front part of the connecting frame portion 42. The compression spring 46 is a compression spring that applies a pressing force to the locking pin 44 toward the inside in the left-right direction of the holder portion 41.

[0043] As described above, the lower pin insertion hole 34 is located near the lower end of the front handrail frame 31a and penetrates it in a left-right direction. When the handrail 5 is slid to the upper position while standing upright behind the support column 2, that is, when the handrail 5 is slid to the upper position above the support column 2 and in the extended position, the lock pin 44 is inserted through it. As a result, the handrail 5 is fixed and held in the extended position above the support column 2 (see Figures 1 and 2).

[0044] On the other hand, the upper pin insertion hole 35 is provided in the front-to-back direction near the upper end of the front handrail frame 31a as described above, and the lock pin 44 is inserted when the handrail 5 is slid to the lower position in a tilted position towards the center between the support posts 2, that is, when the handrail 5 is slid to the lower position below the support posts 2 and is in the folded position. As a result, the handrail 5 is fixed and held in a folded position towards the center between the support posts 2 at the lower position below the support posts 2. In other words, in this embodiment, the overall length and thickness of the ladder 1 are reduced by folding the top plate 4 and the handrail 5 as described above (see Figures 6 and 7).

[0045] Furthermore, in this embodiment, the ladder 1 has upper pin insertion holes 35 located near the upper end of the front handrail frame 31a, extending not only in the front-to-back direction but also in the left-to-right direction. Therefore, even when the handrail 5 is slid downwards in an upright position behind the support column 2, the lock pin 44 is inserted through the upper pin insertion holes 35. As a result, the handrail 5 is fixed and held in an extended position behind the support column 2. In other words, in this embodiment, the ladder 1 allows the installation height (fixed position) of the handrail 5 to be changed vertically when the top plate 4 and handrail 5 are extended and in use.

[0046] Thus, the ladder with a top plate 1 of the above embodiment comprises a pair of left and right support columns 2 extending vertically and arranged side by side at a predetermined interval in the left-right direction, a plurality of rungs 3 horizontally placed between the support columns 2, a top plate 4 horizontally placed above the rungs 3 between the support columns 2, and a pair of left and right handrails 5 provided along each support column 2, wherein the handrails 5 are positioned in an extended position with the handrails 5 raised to the rear of the rear surface 2d of the support columns 2 and in a folded position with the handrails 5 tilted toward the center between the support columns 2. The system includes a handrail support section 9 that supports the top plate 4 in a displaceable manner, and a top plate support section 8 that supports the top plate 4 in a displaceable manner between an extended position where it extends forward of the support column 2 and a folded position where it is tilted downward and in front of the support column 2. The top plate 4 has a hook section 13 that can be engaged with the installation target section P. When in the folded position, it is positioned side by side with the support column 2 in the gap S1 between the two support columns 2, and the hook section 13 is positioned behind the front part 2c of the support column 2 when the top plate 4 is in the folded position.

[0047] With this configuration, the overall thickness of the ladder 1 in its folded state can be reduced by displacing the handrail 5 and the top plate 4 to their respective folded positions, making it easier to carry and reducing storage space. In addition, the unevenness of the front and back of the ladder 1 in its folded state can be reduced, making it less likely to snag on external objects, other ladders 1, or the user's clothing when carrying or stacking multiple ladders 1. This makes it possible to realize a ladder 1 with a top plate that is highly portable and easy to store.

[0048] Furthermore, when both the handrail 5 and the top plate 4 are in the folded position, the hook portion 13 is positioned in front of the outer surface portion 5B of the handrail 5 that faces rear. With this configuration, when the ladder is folded, the hook portion 13 does not protrude behind the outer surface portion 5B of the handrail 5, i.e., behind the ladder 1, making it less likely for the hook portion 13 to get caught on other objects or other ladders 1 when carrying or stacking. Thus, transportability and storage are further improved.

[0049] Furthermore, when the top plate 4 is in the folded position, the step surface 4A is positioned behind the front part 2c of the support column 2. This configuration makes it possible to reduce the overall thickness of the ladder 1 when folded and to reduce the unevenness of the front and rear of the ladder 1, thereby further improving transportability and storage.

[0050] Furthermore, the top plate 4 has a lock pin 15 that is slidably supported on the back surface 4B opposite to the tread surface 4A, and a biasing member 17 that presses and biases the lock pin 15 in one direction of sliding. The top plate support part 8 has a support bracket 21 that is connected to and fixed to the upper end 2T of the support column 2, a support shaft 22 that pivotally connects the top plate 4 to the support bracket 21, a first pin insertion hole 18 that passes through the support bracket 21 and through which the lock pin 15 is inserted when the top plate 4 is in the unfolded position, a second pin insertion hole 19 that passes through the support bracket 21 and through which the lock pin 15 is inserted when the top plate 4 is in the folded position, and a locking piece 23 that is provided on the upper edge of the support bracket 21 and contacts the tread surface 4A of the top plate 4 when the top plate 4 is in the unfolded position.

[0051] With this configuration, when the top plate 4 is in the unfolded position, the lock pin 15 is slid against the biasing force of the biasing member 17 and removed from the first pin insertion hole 18, allowing the top plate 4 to be semi-automatically tilted downward and forward of the support column 2, i.e., towards the folded position, by its own weight. This makes it possible to fold it quickly and easily when carrying it. As a result, a ladder with a top plate 1 with even greater transportability and storage efficiency can be realized.

[0052] Furthermore, with this type of ladder, when the top platform is extended and secured to the installation site, a significant load is placed on the support shaft of the top platform. If this load causes deformation or damage to the support shaft and its surroundings, the top platform will become unstable, impairing its usability. In addition, the entire ladder may not be able to be folded into an appropriate form, potentially compromising its transportability and storage.

[0053] However, with the above configuration, the load applied to the support shaft 22 when in use is distributed to two points, the lock pin 15 and the locking piece 23, making deformation and damage to the support shaft 22 and its surroundings less likely. As a result, the top plate 4 is less loose, and a good user experience can be maintained over a long period of time. In addition, the folded form of the ladder 1 can be maintained over a long period of time, thus realizing a ladder 1 with a top plate that is even more transportable and easier to store. [Explanation of Symbols]

[0054] 1 Ladder with top platform 2 pillars 2c Front part of the support column 2d Rear part of the support column 3 steps 4 Top plate 4A Top panel footrest surface 4B Underside of the top panel 5 Handrail 5B Outer surface of the handrail 8. Top panel support section 9 Handrail support section 13 Hook section 18 First pin insertion hole 19. Second pin insertion hole 21 Support bracket 22 Spindle 23 Locking piece S1 Gap

Claims

1. A ladder with a top plate comprising: a pair of left and right support columns extending vertically and arranged side by side at a predetermined interval in the left-right direction; a plurality of rungs horizontally between the support columns; a top plate horizontally positioned above the rungs between the support columns; and a pair of left and right handrails provided along each of the support columns, A handrail support section that supports the handrail so that it can be displaced between an extended position in which it is raised to the rear of the rear surface of the support column and a folded position in which it is tilted toward the center between the support columns, The system includes a top plate support that supports the top plate so that it can be displaced between an extended position where it extends forward of the support column and a folded position where it is tilted downward and forward of the support column, The top plate has a hook portion that can be attached to the installation target, and when in the folded position, it is positioned horizontally with the support columns in the gap between the two support columns. The aforementioned hook portion is a ladder with a top plate, positioned behind the front portion of the support column when the top plate is in the folded position.

2. The ladder with a top plate according to claim 1, wherein the hook portion is positioned forward of the outer surface portion of the handrail facing the rear when both the handrail and the top plate are in the folded position.

3. The ladder with a top plate according to claim 1, wherein when the top plate is in the folded position, the step surface portion is positioned behind the front portion of the support column.

4. The top plate has a lock pin that is slidably supported on the back surface opposite to the foot plate surface, and a biasing member that presses and biases the lock pin in one direction of sliding. The ladder with a top plate according to any one of claims 1 to 3, wherein the top plate support portion comprises a support bracket fixed to the upper end of the support column, a support shaft pivotally connecting the top plate to the support bracket, a first pin insertion hole through the support bracket through which the lock pin is inserted when the top plate is in the extended position, a second pin insertion hole through the support bracket through which the lock pin is inserted when the top plate is in the folded position, and a locking piece provided on the upper edge of the support bracket that abuts against the tread surface of the top plate when the top plate is in the extended position.

Images