Ladder / stepladder

Abstract

[Problem] To provide a means for preventing the inadvertent operation of a remote control mechanism in a stepladder combined with a ladder, which can be installed without complicating the structure of the remote control mechanism. [Solution] A remote control mechanism that operates to release the lock state of the telescopic leg members by the lock mechanism when an operating force is applied is provided on one of the ladder bodies 2, which is turned upside down when used as a ladder, and a stopper for preventing the operation of the remote control mechanism 8 is swingably attached to an attachment portion 15 fixedly provided on the one of the ladder bodies. When the stepladder combined with a ladder is used as a stepladder, the stopper is placed in a first position where it swings in a first swing direction under its own weight and does not block the operation of the remote control mechanism, and when the stepladder combined with a ladder 1 is used as a ladder, it is placed in a second position where it swings in a second swing direction opposite to the first swing direction under its own weight and can block the operation of the remote control mechanism. [Selected Figure] Figure 6

Description

Technical Field

[0001] The present invention relates to a ladder-cum-stool that can also be used as a ladder, in which the upper ends of two ladder bodies are connected to each other by a hinge fitting so as to be openable and closable, and one ladder body is rotated so as to be turned upside down.

Background Art

[0002] As a ladder-cum-stool, for example, as disclosed in Patent Document 1 below, each ladder body includes, in addition to two columns and a plurality of treads that are stepwise fixed between both columns, a telescopic leg member that is slidably connected to each column to form a leg of the ladder body, a locking mechanism that can lock the telescopic leg member at an arbitrary slide position with respect to the column, and a remote operation mechanism that can release the lock of the telescopic leg member by the locking mechanism when an operating force is applied at an upper position away from the locking mechanism. There is known one having such a structure. The locking mechanism has, for example, a locked portion formed along the length direction of the telescopic leg member, and a locking member provided at the lower part of the ladder body and operable to switch between a locked state of engaging with the locked portion of the telescopic leg member and a unlocked state of releasing the engagement with the locked portion. The remote operation mechanism includes, for example, a transmission member provided along the column and movable in the length direction, an operation portion provided at an upper position (for example, the lower part or the back of the third tread from the bottom) of the locking member of the locking mechanism in the ladder body and operable to move the transmission member in one direction of the length direction by a predetermined operation, and a lower transmission portion that transmits the operation of the transmission member by operating the operation portion to the locking member of the locking mechanism to switch the locking member to the unlocked state.

[0003] Here, in the case of a ladder-cum-stool, when the operation portion for operating the remote operation mechanism is accidentally operated in the ladder body that has been turned upside down when used as a ladder, the lock of the telescopic leg member with the tip upward may be inadvertently released and the telescopic leg member may expand and contract. Therefore, as a means for solving the above problems, as disclosed in Patent Documents 1 and 2 below, a swing stopper is provided at the operating part of the remote control mechanism, and this swing stopper is used to prevent the operation of the remote control mechanism of the ladder body that is turned upside down when used as a ladder. It has been proposed.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] The problem of this invention is to prevent the remote control mechanism of the ladder body that is turned upside down when used as a ladder from operating inadvertently in a ladder-cum-step ladder equipped with a locking mechanism for telescopic leg members and its remote control mechanism. The purpose is to make it possible to install a stopper relatively easily without complicating the structure of the remote control mechanism, and to simplify product assembly.

Means for Solving the Problems

[0006] In order to achieve the above problems, this invention consists of the following aspects.

[0007] 1) A ladder-cum-step ladder in which the upper ends of two ladder bodies are connected to each other by a hinge fitting so as to be openable and closable, and can be used as a ladder by rotating one ladder body so as to turn it upside down. The one ladder body includes two columns, a plurality of treads that are detachably fixed in a stepped manner between both columns, telescopic leg members that are slidably connected to each column and constitute the legs of the one ladder body, a locking mechanism that can lock the telescopic leg members at an arbitrary sliding position with respect to the columns, and a remote operation mechanism that can be operated to release the locking of the telescopic leg members by the locking mechanism when an operating force is applied at a position away from the locking mechanism. A stopper for preventing the operation of the remote operation mechanism is swingably attached to a mounting portion fixedly provided on the one ladder body. When the ladder-cum-step is used as a step, the stopper is arranged at a first position where it swings in a first swing direction by its own weight and does not prevent the operation of the remote operation mechanism. When the ladder-cum-step is used as a ladder, the stopper is arranged at a second position where it swings in a second swing direction opposite to the first swing direction by its own weight and can prevent the operation of the remote operation mechanism. The ladder-cum-step.

[0008] 2) A first engaging portion is formed at a predetermined position of the stopper, and a second engaging portion that can engage with the first engaging portion of the stopper arranged at the second position from the operating direction of the operating portion is formed on the operating portion of the remote operation mechanism that operates in a predetermined operating direction when an operating force is directly or indirectly applied. The ladder-cum-step of 1) above.

[0009] 3) The first engaging portion is formed by a first engaging recess or a first engaging protrusion formed on the side portion of the stopper on the second swing direction side. The second engaging portion is formed by a second engaging protrusion or a second engaging recess formed on the operating portion so as to loosely fit with the first engaging recess or the first engaging protrusion of the stopper arranged at the second position and can engage with the first engaging recess or the first engaging protrusion from the operating direction of the operating portion. The ladder-cum-step of 2) above.

[0010] 4) When the stopper swings in the second swing direction, the bottom of the first engaging recess or the tip of the first engaging protrusion abuts against the tip of the second engaging protrusion or the bottom of the second engaging recess, so that the stopper is held at the second position. The ladder-cum-step of 3) above.

[0011] 5) Among the first engaging portion and the second engaging portion, at least one of them has an engaging surface that is substantially perpendicular to the operating direction of the operating portion when engaging with the other, and the ladder-cum-step stool according to any one of 2) to 4) above.

[0012] 6) The second engaging portion is formed so as to be able to move substantially parallel to one surface in the rocking axis direction of the stopper when the operating portion moves in the operating direction. The first engaging portion protrudes from a predetermined portion of the one surface of the stopper, does not interfere with the second engaging portion that moves at the first position, and can engage with the second engaging portion from the operating direction of the operating portion at the second position, and the ladder-cum-step stool according to 2) above.

[0013] 7) The first engaging portion is formed to protrude from an end portion on the side opposite to the rocking tip across the rocking axis on the one surface of the stopper, and the ladder-cum-step stool according to 6) above.

[0014] 8) The remote operation mechanism has a lifting and lowering operation portion that is lifted or lowered along the column when an operating force is directly or indirectly applied. The attached portion is composed of a bracket fixedly attached to the column and / or the footrest so as to be close to a predetermined portion of the lifting and lowering operation portion. The lifting and lowering operation of the lifting and lowering operation portion is blocked by the stopper arranged at the second position, and the ladder-cum-step stool according to any one of 1) to 8) above.

[0015] 9) The attached portion is provided with a first contacted portion that can contact a first contact portion provided on a side portion on the first rocking direction side of the stopper when the stopper rocks in the first rocking direction and hold the stopper in the first position, and the ladder-cum-step stool according to any one of 1) to 8) above.

[0016] 10) In the first position, the virtual line connecting the swing axis and the swing tip of the stopper is inclined toward the second swing direction side with respect to the vertical line passing through the swing axis. In the second position, the virtual line is inclined toward the first swing direction side with respect to the vertical line passing through the swing axis. The ladder-cum-step stool according to any one of 1) to 9) above.

Effect of the Invention

[0017] According to the ladder-cum-step stool of the present invention, since the stopper for preventing the operation of the remote operation mechanism is swingably attached to the attached portion fixedly provided on the ladder body, the safety when used as a ladder can be surely enhanced without complicating the structure of the remote operation mechanism. Therefore, the product assembly can be simplified. Further, according to the ladder-cum-step stool of the present invention, the installation position of the stopper can be changed relatively easily according to the structure of the remote operation mechanism or the like.

Brief Description of the Drawings

[0018]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Embodiments for Carrying Out the Invention

[0019] [First Embodiment] Figs. 1 to 6 show a ladder-cum-step ladder according to the first embodiment of the present invention. In the following description of this embodiment, the left side of each of FIGS. 2(b) and 3(b) is referred to as "front", the right side of each is referred to as "rear", and "left and right" refers to the left and right when viewed from the front (for example, the left and right of FIGS. 2(a), 3(a), 4(a)(b), and 5(a)(b)). FIGS. 2 and 3 are views seen from the front side or the right side (inner side in the left-right direction) with one ladder body of the ladder-cum-stool arranged such that its length direction faces the vertical direction.

[0020] As shown in FIG. 1 showing the overall configuration, the ladder-cum-stool (1) has the upper ends of two front and rear ladder bodies (2) connected to each other by a hinge fitting (21) so as to be openable and closable. This ladder-cum-stool (1) can also be used as a ladder by rotating one ladder body (2) so as to turn it upside down. The two ladder bodies (2) are substantially identical in shape and size except that they are arranged facing each other front and rear. Therefore, hereinafter, only one ladder body (2) will be described based on the drawings. Also, the ladder body (2) is symmetric about a plane passing through the center line of its left-right width as a symmetric plane, and FIGS. 2 to 6 show only the left part of the ladder body (2), and illustration of the right part of the ladder body (2) is omitted.

[0021] The ladder body (2) includes two left and right support columns (3) and a plurality (five in the figure) of treads (4A)(4B)(4C)(4D)(4E) that are passed and stopped in a stepped manner at intervals in the vertical direction between both support columns (3). The uppermost tread (4E) forms a top plate when the ladder-cum-stool (1) is used as a stool. Also, between the upper parts of the left support columns (3) of the two ladder bodies (2) and between the upper parts of the right support columns (3), opening-stop fittings (22) are passed and stopped respectively.

[0022] Each of the left and right support columns (3) of the ladder body (2) is usually made of a metal profile (preferably, an aluminum alloy profile). Also, the illustrated support column (3) is made of a hollow material having a substantially U-shaped cross section that opens inward in the left-right direction. Each rung (4A) to (4E) is also usually made of a metal profile (preferably, an aluminum alloy profile). Among the rungs shown in the figure, the lowermost rung (4A) and the second rung from the bottom (4B) are each made of a hollow member having a substantially square cross-section. Further, the third rung from the bottom (4C) is made of a hollow member having a substantially U-shaped cross-section that opens downward. Although not shown in the figure, on the upper surface (the surface that becomes the tread surface of both ladder bodies (2) when standing on the ladder, the surface that becomes the tread surface of the lower ladder body (2) when in the ladder state) and the lower surface (the surface that becomes the tread surface of the upper ladder body (2) when in the ladder state) of each rung (4A) to (4E), a plurality of anti-slip convex strip portions and / or concave groove portions extending along the left-right length direction are formed side by side in the front-rear width direction. The left and right ends of the lowermost rung (4A) and the second rung from the bottom (4B) are each attached to the left and right support columns (3) via brackets (41) and (42). The left and right ends of the other rungs (4C), (4D), and (4E) are inserted into the inside of the left and right support columns (3) and are directly attached to the front and rear side walls of the support columns (3) by, for example, rivets. Note that the shapes, attachment structures, etc. of the support columns and rungs constituting the ladder body are not limited to the above-described aspects and can be changed as appropriate.

[0023] In addition to the above configuration, each ladder body (2) is provided with a telescopic leg device (5). The telescopic leg device (5) includes two left and right telescopic leg members (6) that are slidably connected to the left and right support columns (3) and constitute the legs of the ladder body (2), two left and right locking mechanisms (7) that can lock each telescopic leg member (6) at an arbitrary sliding position with respect to each support column (3), and a remote operation mechanism (8) that operates so as to be able to release the lock of the telescopic leg member (6) by the locking mechanism (7) when an operating force is applied at a position away from the locking mechanism (7).

[0024] Each ladder body (2) is further provided with a stopper (13) for preventing the operation of the remote control mechanism (8). The stopper (13) is swingably attached to an attached portion (an upper holding bracket, to be described later) (15) fixedly provided on each ladder body (2). The attached portion (15) is a non-operating portion (fixed portion) that does not perform a predetermined operation in each ladder body (2), specifically, a predetermined portion of the support column (3), the treads (4A) to (4E), and parts such as brackets (41), (42), (14), (15), etc. fixedly attached to the support column (3) and / or the treads (4A) to (4E). When the ladder-cum-step ladder (1) is used as a step ladder (see FIG. 1), the stopper (13) is arranged in a first position where it swings in the first swing direction by its own weight and does not prevent the operation of the remote control mechanism (8) as shown in FIG. 5. On the other hand, when the ladder-cum-step ladder (1) is used as a ladder, the stopper (13) is arranged in a second position where it swings in a second swing direction opposite to the first swing direction by its own weight and can prevent the operation of the remote control mechanism (8) as shown in FIG. 6. In the case of a ladder-cum-step ladder with a specification in which the ladder body (the upper ladder body) that is turned upside down when used as a ladder is limited to one ladder body, the stopper may be provided only on the above-mentioned one ladder body.

[0025] The telescopic leg member (6) is slidably inserted into the support column (3) from its lower end. A grounding portion (61) for enhancing the stability during use is provided at the lower end of the telescopic leg member (6). The telescopic leg member (6) is usually formed from a metal profile (preferably, an aluminum alloy profile). In addition to the configuration in which the telescopic leg member is slidably inserted into the hollow support column as shown in the figure, it may also have a configuration in which it is slidably connected to the outside of the support column (for example, the left and right outer sides of the support column).

[0026] The locking mechanism (7) has a locked portion (71) formed along the length direction of each telescopic leg member (6), and a locking member (72) provided at the lower part of the ladder body (2) and operable to switch between a locked state engaged with the locked portion (71) of each telescopic leg member (6) and an unlocked state in which the engagement with the locked portion (71) is released.

[0027] The locked portion (71) can be constituted by, for example, a rack (71) provided on the inner side surfaces in the left - right direction of each telescopic leg member (6) as shown in the drawing and having a number of teeth (711) arranged along the length direction of the telescopic leg member (6).

[0028] The locking member (72) is swingably attached to the vicinity of the lower end of each column (3) in the ladder body (2), for example, to brackets (41) for attaching the left and right ends of the lowermost rung (4A) to the column (3) as shown in the drawing, with a swing axis (720) extending in the front - rear direction as the center. More specifically, the bracket (41) has a front bracket portion (41a) attached across the front side wall of the column (3) and the end of the front side wall of the lowermost rung (4A), a rear bracket portion (41b) attached across the rear side wall of the column (3) and the end of the rear side wall of the lowermost rung (4A), and a holding frame portion (41c) integrally provided with these to connect the front bracket portion (41a) and the rear bracket portion (41b) above the lowermost rung (4A) and having a substantially U - shaped horizontal cross - section opening toward the column (3). And the swing axis (720) of the locking member (72) is attached across the front and rear side walls of the holding frame portion (41c) of the bracket (41). In addition, the holding frame portion may be constituted by a holding frame member separate from the bracket, in addition to being provided integrally with the bracket as shown in the drawing, and this member may be connected and fixed to the column (3) and / or the lowermost rung (4A). The locking portion (721) extends obliquely downward from the horizontal cylindrical central portion through which the swing axis (720) is inserted, outward in the left - right direction (toward the column side), and a plurality of teeth (721a) engageable with the teeth (711) of the rack (71) are formed at the tip portion thereof (see FIG. 4). This locking member (72) can be swung in a predetermined locking direction (clockwise direction in FIG. 4) about the swing shaft (720), so that the teeth (721a) of the locking portion (721) engage with the teeth (711) of the rack (71) to be in a locked state. By swinging in the unlocking direction opposite to the locking direction (counterclockwise direction in FIG. 4), the engagement between the teeth (721a) of the locking portion (721) and the teeth (711) of the rack (71) is disengaged to be in an unlocked state, and it is switchable between the two. Further, the locking member (72) has a first engaging portion (722) that constitutes a part of the lower transmission portion (11) of the remote operation mechanism (8) described later. The first engaging portion (722) is provided at a portion adjacent to the inner side in the left-right direction of the swing shaft (720) in the locking member (72) and is constituted by an engaging concave portion (722) that is concave toward the swing shaft (720). Although not shown in the figure, the locking member (72) may be provided with an operation handle (for example, an operation lever) that is connected and fixed to at least one of the front and rear ends of the swing shaft (720) and is disposed outside the front and rear side walls of the holding frame portion (41c). By applying a predetermined operating force to the operation handle, the locking member (72) can be swung in the unlocking direction (counterclockwise direction in FIG. 4) to switch to the unlocked state. The locking mechanism is not limited to the illustrated embodiment and can be appropriately changed. For example, the locking member may be provided above the lowermost tread bar (4A) as shown in the figure, incorporated inside the same tread bar (4A), or provided below the same tread bar (4A).

[0029] The remote operation mechanism (8) includes two left and right transmission members (lifting members) (9) provided along each support column (3) and movable in the longitudinal direction, and an operation portion (10) provided above the locking members (72) of the left and right locking mechanisms (7) in the ladder body (2) and operable to move the transmission member (9) in one direction of the longitudinal direction by a predetermined operation. It also has a lower transmission portion (11) that transmits the operation of the transmission member (9) by operating the operation portion (10) to the locking member (72) of each locking mechanism (7) to switch the locking member (72) to the unlocked state. It is sufficient that at least one operating part (10) is provided corresponding to the two left and right transmission members (9), but the operating part (10) may be provided at a plurality of height positions (for example, two height positions corresponding to the upper part and the middle part of the length of the transmission member (9)). The operating part (10) of this embodiment is composed of an operating member (10) which is provided above the locking members (72) of the left and right locking mechanisms (7) in the ladder body (2) and can be operated in a predetermined direction by applying an operating force. Accordingly, the remote operation mechanism (8) is further provided with an upper transmission part (12) which transmits the operation of the operating member (10) to the transmission member (9) to move the transmission member (9) in one direction in the length direction. In this embodiment, the left and right transmission members (9) can be operated by one operating member (10). However, a configuration in which the left and right transmission members (9) are operated by two left and right operating members corresponding to each of them may also be adopted. The operating part may be provided integrally with the corresponding part at the upper part and / or the middle part of the length of each transmission member (9), and in that case, the upper transmission part can be omitted. Although detailed illustration is omitted, the remote operation mechanism (8) may be provided with biasing means for biasing the locking member (72) of the locking mechanism (7) in the locking direction via the lower transmission part (11). Note that the biasing means may be incorporated into the locking mechanism (7) itself to bias the locking member (72) in the locking direction. The remote operation mechanism is not limited to the above-described aspect and can be changed as appropriate. For example, as another aspect of the remote operation mechanism, although illustration is omitted, there are those having two left and right transmission members (rotating members) provided along each support column (3) and rotatable in the circumferential direction, an operating part provided above the locking members (72) of the left and right locking mechanisms (7) in the ladder body (2) and capable of rotating the transmission member by a predetermined operation, and a lower transmission part for transmitting the rotational operation of each transmission member to the locking member (72) of each locking mechanism (7) to switch the locking member (72) to the unlocked state.

[0030] To explain the remote control mechanism (8) of this embodiment in more detail, first, the transmission member (9) is a long member extending along the length direction of the support column (3), for example, a substantially vertically long plate-like body as shown in the figure, and is held by a predetermined holding means so as to be vertically movable along the inner side portions in the left-right direction of each support column (3). As the holding means for the transmission member (9), for example, a plurality (two in the up-and-down direction in the figure) of holding brackets (14) and (15) attached to the support column (3) can be used. Each of the holding brackets (14) and (15) is formed of a substantially U-shaped bent plate piece that opens outward in the left-right direction (toward the support column (3)) when viewed from a plane, and the tip portions of its front and rear side walls are fixed to the front and rear side walls of the support column (3) by rivets or the like. And the transmission member (9) is inserted into the gap formed between the inner side portion in the left-right direction of the support column (3) and the holding brackets (14) and (15) so as to be vertically movable. The lower holding bracket (14) is attached at a height position between the lowermost tread bar (4A) and the second-lowermost tread bar (4B) in the support column (3), more specifically, at a position above the holding frame portion (41c) of the bracket (41). The upper holding bracket (15) is attached at a height position between the third-lowermost tread bar (4C) and the second-lowermost tread bar (4B) in the support column (3). Also, a gap for inserting the transmission member (9) is formed between the inner side portion in the left-right direction of each support column (3) and the end portion of the second-lowermost tread bar (4B) (see FIGS. 1 to 3).

[0031] As shown in detail in FIG. 5, the operating member (10) constituting the operation portion is formed of a long member extending in the left-right direction and is disposed so as to be vertically movable in a recess that opens below the third-lowermost tread bar (4C). More specifically, the illustrated operating member (10) is formed of a cylindrical body having a substantially square cross-section. The operating member (10) has a length such that both of its end portions are disposed near the upper end portions of the left and right transmission members (9) so that it can function as an operating portion for operating the two left and right transmission members (9). Incidentally, the operation member may be configured to be divided into two parts on the left and right at the middle position of its length, and the left and right transmission members (9) may be individually operated by the two operation members on the left and right. In that case, for example, a holding bracket for holding the inner ends in the left-right direction of the two operation members on the left and right may be provided near the middle of the length of the third tread bar (4C) from the bottom.

[0032] The upper transmission part (12) is constituted by an upper transmission member (12) that interlocks and connects the transmission member (9) and the operation member (10). As shown in detail in FIG. 5, the upper transmission member (12) is substantially inverted L-shaped when viewed from the front, and its horizontal part (121) is inserted into the end part of the operation member (10), and its vertical part (122) is connected and fixed to the upper end part of the transmission member (9) by screws or the like. When an upward operating force is applied to the operation member (10) through the lower opening of the third tread bar (4C) from the bottom (pressing the lower wall of the operation member (10) upward with a finger or the like), the operation member (10) is moved upward in the internal space of the tread bar (4C), and in conjunction with this, the upper transmission member (12) and the transmission member (9) are moved upward. In this embodiment, when it is desired to individually unlock the locking members (72) of the left and right locking mechanisms (7), an operating force may be applied only to the part on the same side as the locking mechanism (7) to be unlocked among the left and right side parts of the operation member (10). Also, when it is desired to simultaneously unlock the locking members (72) of the left and right locking mechanisms (7), an operating force may be applied to the left and right side parts or the middle part of the length of the operation member (10). Incidentally, the configuration of the operation member is not limited to the above-described aspect and can be appropriately changed. For example, the operation member may be constituted by two operation members on the left and right that are swingably mounted about an axis extending in the left-right direction and are arranged close to each other on the back surfaces of the substantially left half and the substantially right half of the third tread bar (4C) from the bottom. In this case, an upper transmission part (for example, a cam mechanism) for transmitting the swinging motion of the operation member so that the transmission member can move up and down may be provided at the outer ends in the left-right direction of each operation member and the upper end of the transmission member.

[0033] The lower transmission part (11) is composed of the first engaging part (722) of the above-described locking member (72) and a lower transmission member (110). The lower transmission member (110) has a connecting part (111) connected to the lower end part of the transmission member (9), and a second engaging part (112) that engages with the first engaging part (724) and can operate to switch the locking member (72) between a locked state and an unlocked state. In the case of this embodiment, the lower transmission member (110) is formed by integrally connecting a first member (110A) having a connecting part (111) and a second member (110B) having a second engaging part (112).

[0034] The connecting part (111) of the first member (110A) is substantially U-shaped and open outward in the left-right direction (toward the support column (3)) when viewed from the front. The locking claws formed at the tip ends of the upper and lower walls thereof are engaged with the edges of the upper and lower two locking holes formed at the lower end part of the transmission member (9), whereby the lower transmission member (110) is connected and fixed to the lower end part of the transmission member (9). Note that the connecting means of the lower transmission member to the transmission member is not limited to the above-described mode, and other appropriate means can also be applied. Here, as shown in FIGS. 2 to 4, the holding bracket (14) for holding the lower part of the transmission member (9) is provided with an inward protruding part (141) protruding inward in the left-right direction from the center in the front-rear width of the central wall (14b) connecting the front and rear side walls (14a). The inward protruding part (141) has a top wall (not shown) disposed between the upper and lower walls of the connecting part (111) of the lower transmission member (110). A compression coil spring (not shown) constituting the above-described biasing means is interposed between this top wall and the lower wall of the connecting part (111) of the lower transmission member (110). Due to the spring elastic force of the compression coil spring acting downward on the lower wall of the connecting part (111) of the lower transmission member (110), the locking member (72) is biased in the rocking direction to be in the locked state. Two bolt insertion cylindrical parts (113)(114) extending in the front-rear direction are formed at intervals in the vertical direction on the side wall part of the connecting part (111) of the first member (110A).

[0035] The second member (110B) includes a flat base wall (115), two front and rear rising walls (116) extending upward from the upper surface of the base wall (115), two front and rear hanging walls (117) extending downward from the lower surface of the base wall (115), and an engagement shaft (112) that is long in the front and rear direction and is attached across the lower ends of both hanging walls (117). The second member (110B) is integrally connected by a bolt inserted through the lower bolt insertion cylinder portion (114) of the first member (110A) through the lower portions of both rising walls (116) and a nut screwed onto the tip of the bolt. The engagement shaft (112) constitutes the second engagement portion (112) and is arranged to fit into the first engagement portion (engagement concave portion) (722) of the locking member (72). Also, as shown in FIG. 4, the lower transmission member (110) may be provided with a cover member (110C). The cover member (110C) is a substantially hollow block-shaped member that is open laterally and downward so as to cover the connecting portion (111) of the first member (110A) and both rising walls (116) of the second member (110B). The cover member (110C) is integrally connected to the first member (110A) by a bolt that penetrates the front and rear side walls and communicates with the upper bolt insertion cylinder portion (113) of the first member (110A) and a nut screwed onto the tip of the bolt. Note that the cover member (110C) can also be omitted. In that case, the upper bolt insertion cylinder portion (113) of the first member (110A) is also unnecessary.

[0036] As shown in FIG. 4(a), when the locking member (72) is in the locked state, one side surface (the lower side in the figure) of the first engagement portion (722) and the second engagement portion (engagement shaft) (112) are arranged side by side horizontally so as to be close to or in contact with each other. At this time, the edge of the lower surface of the base wall (115) of the lower transmission member (110) is brought close to or in contact with the upper edge of the holding frame portion (41c) of the bracket (41), and the lower transmission member (110) is biased downward by the spring elastic force of the compression coil spring. With the above configuration, the locked state of the locking member (72) is reliably maintained. On the one hand, when an upward operating force is applied to the operating member (10), the operating member (10), the upper transmission member (12), the transmission member (9), and the lower transmission member (110) are interlocked and moved upward, and the second engaging portion (112) of the lower transmission member (110) presses the side surface of the other side (the upper side in the figure) of the locking member (72) from below. As a result, the locking member (72) swings in the unlocking direction (counterclockwise direction in FIG. 4), and as shown in FIG. 4(b), the engagement with the locked portion (71) is released to enter the unlocked state. As described above, in the ladder-cum-step ladder (1) of this embodiment, the upper transmission member (12), the transmission member (9), and the lower transmission member (110) of the remote operation mechanism (8) form a lifting operation portion (81) that is lifted along the support column (3) when an upward operating force is indirectly applied through the operating member (10). Thereafter, when the application of the operating force to the operating member (10) is stopped, the spring elastic force of the compression coil spring acts downward, so that the lower transmission member (110), the transmission member (9), the upper transmission member (12), and the operating member (10) are interlocked and moved downward. Along with this, the second engaging portion (112) of the lower transmission member (110) moves downward and presses the side surface of one side (the lower side in the figure) of the locking member (72) from above, and then the locking member (72) swings in the locking direction (clockwise direction in FIG. 4), whereby the locking member (72) is returned to the locked state where it engages with the locked portion (71). Note that the configurations of the first engaging portion and the second engaging portion are not limited to the above-described aspects and can be changed as appropriate.

[0037] In this embodiment, as shown in detail in FIGS. 5 and 6, the stopper (13) is attached to a holding bracket (15) for holding the upper part of the lifting operation portion (81) of the remote operation mechanism (8). The holding bracket (15) has a central wall (152) that connects the left and right inner edges of its front and rear side walls (151). The central part of the front-to-rear width of the central wall (152) is notched in a strip shape over the entire length. Inner protruding portions (153) are integrally provided so as to protrude inward in the left-right direction (opposite to the support column (3)) from the left and right edges of the notch. The inner protruding portion (153) has a substantially U-shaped cross-section that opens outward in the left-right direction (toward the support column (3)) when viewed from a plane. The upper part of the inner protruding portion (153) protrudes above the upper edge of the central wall (152) and is formed so as to face the opening of the third step tread (4C) from below. The lower edges of the front and rear side wall portions (153a) of the inner protruding portion (153) are inclined downward toward the outside in the left-right direction. A rectangular opening (154) is formed in the connecting wall portion (153b) between the front and rear side wall portions (153a) of the inner protruding portion (153). As shown in Fig. 5(a), in a state where no operating force is applied to the operating member (10), in other words, in a state where the telescopic leg member (6) is locked by the locking mechanism (7), the end of the operating member (10) is supported by the upper end of the inner protruding portion (153) of the holding bracket (15). The stopper (13) is swingably attached to the holding bracket (15) by a pin (130) that penetrates a predetermined portion in the front-rear direction and spans the front and rear side wall portions (153a) of the inner protruding portion (153) of the holding bracket (15). That is, the holding bracket (15), more specifically, the front and rear side wall portions (153a) of the inner protruding portion (153) of the holding bracket (15) constitute an attached portion (15) for attaching the stopper (13). Also, the pin (130) constitutes a swing axis (130) of the stopper (13). The shape of the stopper (13) is not particularly limited as long as it can swing by a predetermined angle in a predetermined direction by its own weight in accordance with a change in the posture (vertical direction) of the ladder body (2). However, in order for the stopper to swing reliably, it is preferable that its center of gravity is closer to the swing tip. In that sense, it is preferable to have a shape in which the swing axis side is relatively small and the swing tip side is relatively large (for example, a shape that widens towards the swing tip). Also, if the stopper is made symmetric about the line passing through its swing axis and swing tip, effects such as improved assemblability and cost reduction can be achieved. The illustrated stopper (13) is flat with two flat surfaces in the front and rear, and more specifically, it consists of a relatively thin piece that is substantially rounded-sector-shaped when viewed from the front, and a swing axis (130) is provided on the center angle side thereof. The material of the stopper (13) is not particularly limited either, but it can be formed of, for example, a hard resin or metal.

[0038] A first engaging portion (131) is formed at a predetermined location on the stopper (13). On the other hand, a second engaging portion (123) that can engage with the first engaging portion (131) of the stopper (13) arranged at the second position from the operating direction of the elevating operation portion (81) is formed on the elevating operation portion (81) of the remote operation mechanism (8), more specifically, on the upper transmission member (12). The first engaging portion (131) consists of a first engaging recess (131) formed on the side portion (the left side portion in FIG. 5) on the second swinging direction side of the stopper (13). The second engaging portion (123) consists of a second engaging protrusion (123) formed on the surface (the right side surface in FIG. 5) of the vertical portion (122) of the upper transmission member (12) facing the stopper (13). The second engaging protrusion (123) loosely fits into the first engaging recess (131) of the stopper (13) arranged at the second position and can engage with the first engaging recess (131) from the operating direction of the elevating operation portion (81). The first engaging concave portion (131) has both of its side surfaces formed into gentle arc shapes centered on the rocking axis of the stopper. Correspondingly, the upper and lower side surfaces of the second engaging convex portion (123) are also formed into gentle arc shapes. Thereby, the fitting and release of the first engaging concave portion (131) and the second engaging convex portion (123) accompanying the rocking of the stopper (13) are smoothly performed. As shown in FIG. 5, when the stopper (13) rocks in the first rocking direction, a first abutting portion (132) provided on the side portion on the first rocking direction side thereof abuts against a first abutted portion (154a) formed by the lower edge of the opening portion (154) of the holding stopper (mounting portion) (15), so that the stopper is held at the first position. According to the above configuration, when the ladder-cum-step ladder (1) is used as a step ladder, since the stopper (13) is surely held at the first position, there is no possibility of hindering the operation of the elevating operation portion (81) of the remote operation mechanism (8). On the other hand, as shown in FIG. 6, when the stopper (13) rocks in the second rocking direction, the bottom (131a) of the first engaging concave portion (131) and the tip (123a) of the second engaging convex portion (123) abut against each other, so that the stopper is held at the second position. According to the above configuration, when the ladder-cum-step ladder (1) is used as a ladder with one of its ladder bodies (2) turned upside down, the stopper (13) of the upside-down ladder body (2) is surely held at the second position, so that the operation of the elevating operation portion (81) of the remote operation mechanism (8) can be surely blocked. The first engaging concave portion (131) and the second engaging convex portion (123) have engaging surfaces (131b) (123b) that are substantially perpendicular to the operation direction of the elevating operation portion (81) when engaging with each other (see FIG. 6). Due to the presence of these engaging surfaces (131b) (123b), the engaged first engaging concave portion (131) and second engaging convex portion (123) do not accidentally shift or become disengaged, and the operation of the elevating operation portion (81) is surely blocked by the stopper (13). The engaging surface may be formed on at least one of the first engaging concave portion (131) and the second engaging convex portion (123). Incidentally, contrary to the above aspect, the first engaging portion of the stopper may be a first engaging convex portion, and the second engaging portion of the elevating operation portion may be a second engaging concave portion.

[0039] As shown in FIG. 5, in the first position, the virtual line (L1) connecting the swing axis (130) and the swing tip of the stopper (13) is inclined toward the second swing direction side (the right side in FIG. 5) with respect to the vertical line (L2) passing through the swing axis (130). Also, as shown in FIG. 6, in the second position, the virtual line (L1) of the stopper (13) is inclined toward the first swing direction side (the left side in FIG. 6) with respect to the vertical line (L2) passing through the swing axis (130). If the stopper (13) is arranged as described above in the first position and the second position, when the posture (vertical direction) of the ladder body (2) changes, the stopper (13) smoothly and surely swings in the first swing direction or the second swing direction due to its own weight. Therefore, the function as the stopper (13) is more surely exhibited.

[0040] Next, with reference to FIGS. 5 and 6, a blocking mechanism for the unlocking operation of the remote operation mechanism (8) by the stopper (13) will be described. As shown in FIG. 5, when the ladder-cum-step ladder (1) is used as a step ladder, the stopper (13) swings in the first swing direction (clockwise direction in FIGS. 5(b) and 5(d)) due to its own weight and is arranged at the first position where it does not block the operation of the lifting and lowering operation part (81) of the remote operation mechanism (8) (upward movement along the length direction of the support column (3)). More specifically, the stopper (13) is arranged at a position where its first engaging recess (131) does not interfere with the first engaging protrusion of the upper transmission member during the operation of the lifting and lowering operation part (81). At this time, the first contact part (132) of the stopper (13) is in contact with the first contacted part (154a) of the holding bracket (15), whereby the stopper (13) is surely held at the first position, and thus there is no possibility that the operation of the lifting and lowering operation part (81) of the remote operation mechanism (8) is hindered by the stopper (13). On the one hand, as shown in FIG. 6, when one ladder body (2) is rotated to be turned upside down in order to use the ladder-cum-step ladder (1) as a ladder, the stopper (13) provided on the ladder body (2) swings from the first position toward the second swinging direction (counterclockwise direction in FIG. 6) due to its own weight and is arranged at the second position where it can block the operation of the lifting and lowering operation part (81) of the remote operation mechanism (8). More specifically, when the stopper swings in the second swinging direction, the first engaging recess (131) of the stopper (13) and the second engaging protrusion (123) of the upper transmission member (12) are loosely fitted together, and the bottom (131a) of the first engaging recess (131) and the tip (123a) of the second engaging protrusion (123) come into contact with each other, whereby the stopper (13) is arranged at the second position and held at the same position. In this state, even if an operating force (a force pressing downward in FIG. 6) is inadvertently applied to the operating member (10), for example, the engaging surface (131b) of the first engaging recess (131) and the engaging surface (123b) of the second engaging protrusion (123) are engaged from both sides in the operating direction of the lifting and lowering operation part (81) of the remote operation mechanism (8), so that the operation of the lifting and lowering operation part (81) of the remote operation mechanism (8) is blocked thereby, and consequently, the unlocking of the telescopic leg member by the locking mechanism is prevented from being inadvertently released. Further, when the upper ladder body (2) is rotated to be turned upside down again in order to use the ladder-cum-step ladder (1) used as a ladder as a step ladder again, the stopper (13) provided on the ladder body (2) swings from the second position toward the first swinging direction due to its own weight and is rearranged at the first position as shown in FIG. 5(a).

[0041] As described above, according to the ladder-cum-step ladder (1) of the first embodiment, in the ladder body (2) that is turned upside down when used as a ladder, the remote operation mechanism (8) for remotely operating the locking mechanism (7) of the telescopic leg member (6) provided in the ladder body (2) can be surely blocked by the stopper (13) from operating inadvertently, that is, the locked state of the telescopic leg member (6) by the locking mechanism (7) from being inadvertently released, so that the safety during use is further enhanced. In addition, the stopper (13) swings in a predetermined direction by its own weight in response to a change in the posture (vertical direction) of the ladder body (2), and is automatically arranged at the first position or the second position. Therefore, it can function reliably without requiring any special operation and is excellent in convenience. And since the stopper (13) is attached to a holding bracket (15) (a part to be attached), which holds the upper part of the elevating operation part (81) of the remote operation mechanism (8), there is no need to provide a structure for attaching the stopper (13) to the remote operation mechanism (8), and it is possible to avoid complicating the structure of the remote operation mechanism (8). Furthermore, in this embodiment, a so-called hook-type stopper (13) (an operation blocking mechanism by the engagement of the first engaging concave part (131) and the second engaging convex part (123)) is used as the stopper (13). Therefore, the stopper (13) is more likely to be held at the second position, and the function of the stopper (13) to prevent an accidental operation of the remote operation mechanism (8) when used as a ladder is more surely achieved. In addition, in this embodiment, since the stopper (13) is provided near the operation part (10), it is easy for the user to know through the hand trying to operate the operation part (10) that the remote operation mechanism (8) is in a locked state where its operation is blocked by the stopper (13).

[0042] [Second Embodiment] Figs. 7 to 9 show a part of the ladder-cum-stool according to the second embodiment of the present invention. In the following description regarding this embodiment, the left side of each of Figs. 7(a) and 8(a) is referred to as "front", the right side thereof is referred to as "rear", and "left and right" refers to the left and right when viewed from the front (the left and right of each of Figs. 7(b), 8(b), and 9). The ladder-cum-stool of the second embodiment is substantially the same as the ladder-cum-stool (1) of the first embodiment shown in Figs. 1 to 6, except for the following points. That is, in the ladder-cum-stool of the second embodiment, the stopper (13X) of the ladder body (2X) is provided close to the lower part of the lifting operation part (81) and can prevent the operation of the lifting operation part (81) when used as a ladder. The stopper (13X) is attached to the outer surface of the front side wall part (141a) of the inner protruding part (141) of the lower holding bracket (14) (the part to be attached) for holding the transmission member (9), more specifically, so as to be swingable about a swing shaft (130X) extending in the front-rear direction.

[0043] Similar to the stopper (13) of the first embodiment, the shape of the stopper (13X) is not particularly limited as long as it can swing by a predetermined angle in a predetermined direction by its own weight according to the change in the posture (vertical direction) of the ladder body (2X). For example, it can be a flat shape having two flat surfaces in the front and rear as shown in the figure. More specifically, the illustrated stopper (13) is substantially fan-shaped when viewed from the front, and the swing shaft (130X) is provided on the center angle side thereof. Although detailed illustration is omitted, the swing shaft (130X) is provided so as to protrude rearward from a predetermined position on the rear surface of the stopper and is constituted by an insertion part rotatably inserted into a hole (not shown) formed in the front side wall part (141a) of the inner protruding part (141). With the swing shaft (130X) configured as above, even when a compression coil spring is arranged inside the inner protruding part (141), the stopper (13X) can be easily attached to the attachment part composed of the holding bracket (14) (more specifically, the front side wall part (141a) of the inner protruding part (141)) without interfering with the compression coil spring. However, the configuration of the swing shaft and the attachment structure of the stopper to the attachment part are not limited to the above mode, and other appropriate modes can also be adopted.

[0044] A first engaging part (131X) is formed at a predetermined position on the stopper (13X). On the other hand, a second engaging part (116a) that can engage with the first engaging part (131X) of the stopper (13X) arranged at the second position from the operation direction of the lifting operation part (81) is formed on the lifting operation part (81) of the remote operation mechanism (8), more specifically, on the lower transmission member (110). The first engaging portion (131X) is formed so as to project forward from a predetermined position on the front surface of the stopper (13X), more specifically, from an end portion on the side opposite to the swinging tip across the swinging axis (131X) on the front surface of the stopper (13). The first engaging portion (131X) of the illustrated stopper is formed in a substantially shallow V shape as viewed from the front so as to follow the contour shape of the end portion on the side opposite to the swinging tip. However, the arrangement and shape of the first engaging portion are not limited to the above-described aspect. For example, the first engaging portion can also be constituted by the other end portion on the swinging tip side of the stopper. The second engaging portion (116a) is constituted by the upper end portion (116a) of the front rising wall (116) of the lower transmission member (110). When the lifting and lowering operation portion (81) of the remote operation mechanism (8) operates in the operation direction, the second engaging portion (116a) is adapted to move substantially parallel to the front surface of the stopper (13X). The first engaging portion (131X) of the stopper (13X) in the first position does not interfere with the second engaging portion (116a) that moves with the operation of the lifting and lowering operation portion (81). On the other hand, the first engaging portion (113X) of the stopper (13X) in the second position is adapted to engage with the second engaging portion (116a) from the operation direction of the lifting and lowering operation portion (81). As shown in FIGS. 7 and 8, when the stopper (13X) swings in the first swinging direction (clockwise direction in FIGS. 7(b) and 8(b)), the first contact portion (132X) provided on the side portion (lower side portion in the figure) on the first swinging direction side of the stopper (13X) abuts against the first portion to be contacted (142) formed by the protruding strip portion on the lower edge portion of the outer surface of the front side wall portion (141a) of the inward protruding portion (141), so that the stopper (13X) is held in the first position. According to the above configuration, when the ladder-cum-step ladder (1) is used as a step ladder, since the stopper (13X) is surely held in the first position, there is no possibility of interfering with the operation of the lifting and lowering operation portion (81) of the remote operation mechanism (8). On the one hand, as shown in FIG. 9, when the stopper (13X) swings in the second swing direction (counterclockwise direction in FIG. 9), the second contact portion (133) provided on the side portion on the second swing direction side (the right side portion in the figure) abuts against the second contact portion (143) formed by the outer surface of the central wall (14b) of the lower holding bracket (14), and thus is held in the second position. According to the above configuration, when the ladder-cum-step ladder is used as a ladder, the stopper (13X) of the ladder body (2) turned upside down is surely held in the second position, so that the operation of the lifting and lowering operation portion (81) of the remote operation mechanism (8) can be surely blocked. In addition, in this embodiment, a stopper receiving portion (144) formed of a convex strip portion is formed at a position on the outer surface of the front side wall portion (141a) of the inward protruding portion (141) on the side opposite to the first contact portion (142) with the stopper (13X) interposed therebetween. When an operating force is applied to the operating portion (10), a downward force as shown in FIG. 9 acts on the stopper (13X) through the second engaging portion (116a) of the lifting and lowering operation portion (81). At this time, the stopper (13X) is received from below by the stopper receiving portion (144). Therefore, a large force does not act on the swing axis (130X) of the stopper (13X), and even when the swing axis (130X) is configured by an insertion portion as described above, its breakage can be avoided, and excellent durability can be obtained. The first engaging portion (131X) and the second engaging portion (116a) have engaging surfaces (131S) (116S) that are substantially perpendicular to the operating direction of the lifting and lowering operation portion (81) when engaging with each other (see FIG. 9). Due to the presence of these engaging surfaces (131S) (116S), the first engaging portion (131X) and the second engaging portion (116a) that are engaged with each other do not accidentally shift or become disengaged, and the operation of the lifting and lowering operation portion (81) is surely blocked by the stopper (13X). The engaging surface may be formed on at least one of the first engaging portion (131X) and the second engaging portion (116a).

[0045] Even in the case of the ladder-cum-step ladder according to the second embodiment, the stopper (13X) provided on the ladder body (2X) functions almost in the same manner as the stopper (13) provided on the ladder body (2) of the ladder-cum-step ladder (1) according to the first embodiment, and thereby, an effect almost similar to that of the ladder-cum-step ladder (1) according to the first embodiment is achieved. Also, in the case of the stopper (13X) according to the second embodiment, the first engaging portion (131X) is provided at a portion closer to the swing axis (130X), and since the moving range of the first engaging portion (131X) accompanying the swing of the stopper (13X) becomes smaller, the size and shape of the second engaging portion (116a) that engages with the first engaging portion (131X) can be made compact.

[0046] In each of the above embodiments, the stoppers (13)(13X) are attached to the attached portion formed by brackets (14)(15) for operably holding the elevating operation portion (81). However, as described above, the attached portion is not limited to these brackets (14)(15), and it is also possible to configure it with other fixed portions (non-operating portions) that do not perform a predetermined operation on the ladder body. Specifically, for example, the attached portion may be provided at any location such as the support column (3), the treads (4A) to (4E), and the brackets (41)(42) of the ladder bodies (2)(2X).

[0047] As shown in each of the above embodiments, the stopper according to the present invention is suitably used for a ladder-cum-step ladder provided with a locking mechanism for a telescopic leg member and its remote operation mechanism. However, in addition, there are cases where it is used, stored, and transported in a posture different from the normal one (changing the vertical direction or the inclination angle with respect to the horizontal plane), and for various articles provided with a predetermined operation mechanism, it is widely applicable for the purpose of preventing an inadvertent operation of the operation mechanism in that posture. Specifically, for example, the stopper according to the present invention can also be applied to a dedicated step ladder, a ladder, a portable workbench, etc. provided with a locking mechanism such as a telescopic leg, an anti-tipping / slipping device, a door stopper, and a guide bar as an operation mechanism.

Industrial Applicability

[0048] This invention is suitably used for a ladder-cum-stool provided with a locking mechanism for a telescopic leg member and its remote operation mechanism.

Explanation of Signs

[0049] (1): Ladder-cum-stool (2)(2X): Ladder body (21): Hinge fitting (3): Support column (4A)(4B)(4C)(4D)(4E): Rung (5): Telescopic leg device (6): Telescopic leg member (7): Locking mechanism (71): Locked portion (72): Locking member (8): Remote operation mechanism (81): Lifting operation portion (operation portion) (9): Transmission member (10): Operating member (operation portion) (11): Lower transmission portion (110): Lower transmission member (110A): First member (110B): Second member (116a): Second engaging portion (116S): Engaging surface of the second engaging portion (12): Upper transmission member (upper transmission portion) (123): Second engaging projection (second engaging portion) (123a): Tip of the second engaging projection (123b): Engaging surface of the second engaging projection (13): Stopper (130): Rocking shaft (131): First engaging recess (first engaging portion) (131a): Bottom of the first engaging recess (131b): Engaging surface of the first engaging recess (132): First abutting portion (13X): Stopper (130X): Rocking shaft (131X): First engaging portion (131S): Engaging surface of the first engaging portion (132X): First abutting portion (14): Lower holding bracket (bracket / attached part) (142): First contact part (15): Upper holding bracket (bracket / attached part) (154a): First contact part (L1): Virtual line connecting the swing axis and the swing tip of the stopper (L2): Vertical line passing through the swing axis of the stopper

Claims

1. A ladder-cum-step-stool that can also be used as a ladder, wherein the upper ends of two ladder bodies are connected by a hinge fitting so as to be openable and closable, and one of the ladder bodies can be rotated to be turned upside down. One of the ladder bodies includes two columns, a plurality of treads that are stepped and fixed between both columns, a telescopic leg member that is slidably connected to each column and constitutes the leg of one of the ladder bodies, a locking mechanism that can lock the telescopic leg member at an arbitrary sliding position with respect to the column, and a remote operation mechanism that can operate to release the lock of the telescopic leg member by the locking mechanism when an operating force is applied at a position away from the locking mechanism. A stopper for preventing the operation of the remote operation mechanism is swingably attached to a mounting portion fixedly provided on one of the ladder bodies. The stopper is arranged at a first position where it swings in a first swing direction by its own weight and does not prevent the operation of the remote operation mechanism when the ladder-cum-step-stool is used as a step-stool, and is arranged at a second position where it swings in a second swing direction opposite to the first swing direction by its own weight and can prevent the operation of the remote operation mechanism when the ladder-cum-step-stool is used as a ladder.

2. A first engaging portion is formed at a predetermined position of the stopper, and a second engaging portion that can engage with the first engaging portion of the stopper arranged at the second position from the operating direction of the operating portion is formed on the operating portion of the remote operation mechanism that operates in a predetermined operating direction when an operating force is directly or indirectly applied. The ladder-cum-step-stool according to Claim 1.

3. The first engaging portion is formed by a first engaging recess or a first engaging protrusion formed on the side portion of the stopper on the second swing direction side. The second engaging portion is formed by a second engaging protrusion or a second engaging recess formed on the operating portion so as to loosely fit with the first engaging recess or the first engaging protrusion of the stopper arranged at the second position and can engage with the first engaging recess or the first engaging protrusion from the operating direction of the operating portion. The ladder-cum-step-stool according to Claim 2.

4. When the stopper swings in the second swing direction, the bottom of the first engaging recess or the tip of the first engaging protrusion abuts against the tip of the second engaging protrusion or the bottom of the second engaging recess, so that the stopper is held at the second position. The ladder-cum-step-stool according to Claim 3.

5. The stepladder-cum-stool according to claim 2, wherein at least one of the first engaging portion and the second engaging portion has an engaging surface that is substantially perpendicular to the operating direction of the operating portion when engaging with the other.

6. The second engaging portion is formed so as to be movable substantially parallel to one surface in the swing axis direction of the stopper when the operating portion moves in the operating direction. The first engaging portion protrudes from a predetermined location on the one surface of the stopper, does not interfere with the second engaging portion that moves in the first position, and is formed so as to be engageable with the second engaging portion from the operating direction of the operating portion in the second position. The stepladder-cum-stool according to claim 2.

7. The first engaging portion according to claim 6, wherein the first engaging portion is formed to protrude from an end portion on the side opposite to the swing tip across the swing axis on the one surface of the stopper.

8. The remote operation mechanism has a lifting and lowering operation portion that is lifted or lowered along the support column when an operating force is directly or indirectly applied. The attached portion is composed of a bracket fixedly attached to the support column and / or the step rail so as to be close to a predetermined location of the lifting and lowering operation portion. The stepladder-cum-stool according to claim 1, wherein the lifting and lowering operation of the lifting and lowering operation portion is blocked by a stopper disposed at the second position.

9. The attached portion is provided with a first abutted portion that can abut against a first abutting portion provided on the side portion on the first swing direction side of the stopper when the stopper swings in the first swing direction to hold the stopper in the first position. The stepladder-cum-stool according to claim 1.

10. In the first position, the virtual line connecting the swing axis and the swing tip of the stopper is inclined toward the second swing direction side with respect to the vertical line passing through the swing axis. In the second position, the virtual line is inclined toward the first swing direction side with respect to the vertical line passing through the swing axis. The stepladder-cum-stool according to claim 1.

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