JPH08270166A - Folding ladder device - Google Patents

Abstract

PURPOSE: To enable stable and smooth opening and closing of a lid and extension and contraction performance of a ladder for a long time by improving the durability of the ladder through reducing a load applied on a hinge of the lid for the ladder device whose upper ladder part of a folding ladder is fixed to the lid, by the rotation of which the opening and closing of the ceiling part of the ladder can be conducted. CONSTITUTION: A tip of a belt 33 having both ends is fixed to a tip of the lid 10. After the belt 33 is wound and crossed over guide pulleys 30, 30 which is located upper side than the hinge 11 of the lid 10, a base end of the belt is connected to a take-up device 37. The tip part of the lid is provided with a fixed pulley 40 which is correspondingly arranged against the belt fixed member 31, and a ladder fixed member 20 which has a guide hole 42 extending parallel with the lid 10 on the baser end side of the lid than the fixed pulley 40. A moving pulley 44 movable along the guide hole 42 is also provided. The moving pulley 44 and an end part of a medium step ladder part 15 on the side of upper-most step ladder part 14, are connected with a link material 46 and the belt 33 is connected starting from the tip side up to the take-up device 37 through sequentially wound around the moving pulley 44 and also around the fixed pulley 40 thereafter.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a folding ladder device having a ladder that is folded in three stages, and more particularly to a folding ladder device that automatically performs the folding and extending operations of the ladder.

[0002]

2. Description of the Related Art Conventionally, an example of a folding ladder device of this type is disclosed in Japanese Patent Application Laid-Open No. 63-181845. This consists of a frame that is placed around the ceiling opening and attached, a lid that is rotatably supported by this frame and that opens and closes the ceiling opening, and the three upper, middle, and lower ladders. And a folding ladder that is folded into a substantially N-shape. The upper end of the upper ladder portion is rotatably connected to the frame body above the support portion of the lid, while the lower end is attached to the lid along the guide. Slidably connected and the shaft of the drive unit attached to the lid expands and contracts to slide the connecting portion of the upper ladder portion to the lid along the guide to relatively change the positions of the lid and the upper ladder portion. By doing so, the lid is opened and closed.

Further, in order to fold and extend the middle ladder portion with respect to the upper ladder portion of the ladder, the link fitting is moved by the drive device.

[0004]

However, in this conventional device, since the drive device is attached to the lid itself,
A large load is applied to each of the hinges for connecting the lid and the folding ladder (upper ladder portion) to the frame body at each attachment portion.

In addition, since the driving device pushes the link metal fittings, the load on the connecting portion of the lid and the ladder to the frame body becomes very heavy in this respect as well as the opening and closing of the lid. There is a possibility of falling off and deformation, and there was room for improvement.

The present invention has been made in view of the above circumstances, and an object thereof is to improve the mechanism for opening and closing the lid and extending and retracting the folding ladder to thereby rotationally connect the lid and the folding ladder. The load on the part is reduced to prevent the connecting part from falling off or deforming, improving its durability, and opening / closing the lid and expanding / contracting the folding ladder stably and smoothly over a long period of time. Is to

[0007]

In order to achieve the above object, according to the present invention, the end of a belt member having an end is connected to the end of a lid while being wound around a predetermined pulley. By winding and unwinding the base end side on the frame side, the lid is opened / closed and the folding ladder is extended / contracted while the pulley is moved.

[0008] Specifically, in the invention of claim 1, a frame body arranged around and fixed to a ceiling opening of a room, and a base end thereof is rotatably attached to the frame, and the ceiling opening is provided. A lid for opening and closing, an upper ladder portion fixed to the back surface of the lid, an intermediate ladder portion whose one end is rotatably connected to an end portion of the upper ladder portion on the tip side of the lid, and one end portion of which is the intermediate ladder. Folding ladder device comprising a lower ladder part that is rotatably connected to the other end of the part, and a folding ladder that is housed in the ceiling opening when each of the ladder parts is folded into a substantially N shape when housed. Is the premise.

Then, a belt fixing portion provided at the tip of the lid, a belt guide member provided in a frame above the base attaching portion of the lid, and the tip of the belt fixing portion being attached and fixed to the belt fixing portion. A belt winding device, in which an intermediate portion is provided on an endless belt member that is wound around the belt guide portion and a frame body near the mounting portion of the lid, and the belt member can be wound and unwound at the base end side. And a means for winding and unwinding the belt member by the belt winding means to open and close the lid.

According to a second aspect of the present invention, in the folding ladder device according to the first aspect, a fixed pulley which is immovably supported by the tip of the lid in correspondence with the belt fixing portion, and a tip of the lid are provided. A supporting member having a guide portion extending substantially parallel to the lid on the base end side of the fixed pulley and along the lid, a movable pulley movably supported by the guide portion of the supporting member, and one end portion of The first link member is rotatably connected to the shaft portion of the moving pulley, and the other end portion is rotatably connected to an end portion on the upper ladder portion side in the middle ladder portion of the folding ladder.

Then, the belt member is bent from the belt fixing portion side (tip side) toward the winding device side (base end side) toward the fixed pulley side at the base end side of the lid of the moving pulley, and then the fixed pulley. It is hung on both pulleys so that it bends toward the base end side of the lid at the end side of the lid, and with the lid open, the moving pulley is guided to the support member by the winding and unwinding operation of the belt member by the belt winding means. It is configured to be moved along and to rotate the middle ladder section around the connection point with the upper ladder section via the first link member.

According to a third aspect of the present invention, in the folding ladder device according to the first or second aspect, one end of the folding ladder is rotatably supported by the tip of the lid, and the other end of the folding ladder is the lower ladder of the folding ladder. A second link member that is rotatably connected to the intermediate portion and that adjusts an opening angle with the middle ladder portion of the lower ladder portion is provided.

According to a fourth aspect of the present invention, in the folding ladder device of the third aspect, a lever member whose base end is rotatably connected to a shaft portion of the second link member on the tip side of the lid, and a lever member of the lever member. Urging means connected to the tip end portion for urging and biasing the lever member so that the folding ladder is extended.

[0014]

With the above construction, in the invention of claim 1, when the ceiling opening is closed by the lid, the belt member whose front end is attached and fixed to the belt fixing portion at the front end of the lid has its base end side. The belt winding means is wound around and pulled by the belt winding means, and the intermediate portion of the belt member is wound around the belt guide member. Since this belt guide member is provided on the frame body above the base end mounting portion of the lid, the lid is in a state of being suspended by pulling the tip end portion thereof by the belt member. The lid is fixedly held in the closed state.

When the lid is opened from this state, the belt member is paid out from the belt winding means. As the belt member is unwound from the winding means, the tensile force of the belt member decreases, so the lid pivots about its base end and opens.
The belt member extends from the winding means via the belt guide.
Then, when the lid reaches the open position, the lid is stopped and held in the open position.

On the other hand, when the lid is closed, on the other hand, the belt winding means winds the belt member, and the tip of the lid, to which the tip of the belt member is fixed, is pulled toward the belt guide member. Therefore, the tip of the lid is pulled up and rotated in the closing direction. When the lid is rotated to the closed position, the winding of the belt member by the belt winding means is stopped, and the lid is stopped and held in the closed position. It

In this case, the belt winding means as a driving device is attached to the frame body side fixed to the ceiling opening, that is, the ceiling side of the building, and the belt member is wound by the belt winding means so that the tip of the lid is closed. Pull the belt fixing part in the vicinity and pull up the lid in the open state against the weight of the folding ladder and the lid to close it.On the other hand, when opening and lowering the lid, wind the belt member by the weight of the folding ladder and the lid. All you have to do is to take it out from the taker. Therefore, the load on the connecting portion of the base end portion of the lid to the frame is extremely small, and its durability can be ensured, and the lid can be smoothly moved depending on the speed of winding or winding the belt member by the belt winding means. Can be opened and closed.

According to the second aspect of the invention, the intermediate portion of the belt member is bent toward the fixed pulley side at the base end side of the lid of the movable pulley from the front end side to the base end side of the fixed and movable pulleys. Since the fixed pulley is hung so as to bend toward the base end side of the lid at the tip side of the lid, when the lid is in the open state as described above, the moving pulley has both sides of the belt member wound around it. Is pulled toward the tip side of the lid and is positioned at an end position on the tip side of the lid of the guide portion of the support member.

Further, one end of the first link member is connected to the shaft portion of the moving pulley, and the other end of the first link member is connected to an end portion of the folding ladder in the middle ladder portion on the upper ladder portion side. Therefore, when the middle ladder portion of the folding ladder has a force to rotate in the extension direction due to its own weight in the open state, the force acts on the moving pulley via the first link member, The moving pulley is urged in the direction toward the base end side of the lid along the guide portion of the support member.

When the ladder folded into a substantially N-shape is extended from the open state, the belt member is further extended and extended from the belt winding means. With this feeding of the belt member, the belt member moves toward the moving pulley while rotating it through the fixed pulley, and the tensile force of the belt member pulling the moving pulley becomes small,
The movable pulley is moved to the base end side of the lid along the guide part of the support member by the rotating force by the self-weight of the middle ladder part, which allows the middle ladder part to rotate in the extension direction, which is performed. . Then, when the middle ladder portion is rotated so as to be aligned with the upper ladder portion and the ladder is extended, the moving pulley is positioned at the end position on the lid base end side of the guide portion and the belt winding is performed in this state. The feeding means stops the feeding of the belt member, and the ladder is held in the extended state.

On the other hand, when folding the ladder in the extended state, the belt member is wound by the belt winding means,
Along with this winding, the movable pulley is pulled toward the tip of the lid between the fixed pulley and the belt fixing portion, and the movable pulley moves from the end position on the lid proximal end side to the tip of the lid along the guide portion. Due to the movement of the moving pulley, the first link member, the end portion of which is connected to the moving pulley, changes its posture and pushes the upper ladder side end portion of the middle ladder portion, and the middle ladder portion is the lower ladder portion side end portion. Is raised together with the lower ladder and turned toward the upper ladder, and bending of the ladder begins. Then, when the movable pulley is positioned at the end position on the lid tip side of the guide portion, it returns to the initial state and the folding ladder is folded.

Therefore, even when the ladder expands and contracts when the lid is open, the load on the connecting portion of the lid is small, and the durability can be ensured, and the speeds of winding and unwinding the belt member can be increased. It enables smooth expansion and contraction.

According to the third aspect of the present invention, one end of the second link member is pivotally supported by the tip of the lid, and the other end of the second link member is rotatable to the intermediate portion of the lower ladder of the folding ladder. The lower ladder part of the ladder is connected not only via the upper ladder part and the middle ladder part fixed to the lid but also at the middle part of the lower ladder part with the tip of the lid. It will be connected via two link materials. Therefore, when the ladder is expanded and contracted in the open state, the middle and lower ladder parts are connected to each other at the connection points of the upper and middle ladder parts, the connection points of the middle and lower ladder parts,
Rotate like a magic hand while maintaining a substantially parallelogram having four vertexes at the connecting points of the lower ladder portion and the second link material and the connecting points of the second link material to the tip of the lid. . Therefore, the lower ladder portion is stably rotated and the opening angle thereof is regulated, and there is no fear of the user hitting the head or pinching a finger due to the abrupt rotation of the lower ladder portion. .

According to the fourth aspect of the present invention, the base end portion of the lever member is rotatably connected to the shaft portion of the second link member on the tip end side of the lid, and the biasing means is connected to the tip end portion of the lever member. The lever member is pivotally biased by the biasing means so that the folding ladder is extended, so that the center of gravity of the lever member is on the lid side when the middle and lower ladder portions start to open when the lid is opened. Also, by the rotational biasing force of the biasing means,
Its center of gravity can be quickly moved away from the lid, and the extension operation of the ladder can be performed automatically.

[0025]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 4, reference numeral 1 denotes a ceiling of a room, and a storage room 2 such as an attic is formed above the ceiling of the room. A rectangular opening 3 is opened at a predetermined position of the ceiling 1, and a plurality of plate members 5a, 5a, ... Having a vertical width are assembled in a rectangular shape at the peripheral edge of the ceiling opening 3. A frame 5 having a predetermined height is attached and fixed. One end side (the right side in each drawing) of the frame body 5 in the length direction is a lid mounting side, and a lid 10 for opening and closing the ceiling opening 3 in the frame body 5 is provided at the lower end of the plate material 5a on the lid mounting side. It is rotatably attached by a hinge 11 at its base end. The lid 10 has a horizontal position and a closed position where the ceiling opening 3 in the frame 5 is closed, and an inclined position in which the tip portion hangs down so as to form a predetermined angle θ with the ceiling 1. Rotate between open and open positions.

Further, the frame body 5 has a frame-shaped frame body extension portion 6 extended so that the plate material 5a on the lid mounting side which supports the base end portion of the lid 10 serves as a partition wall. The extension portion 6 is formed with a motor housing chamber 7 whose upper and lower open portions are closed.

A folding ladder 13 is attached to the rear surface (surface on the side of the storage chamber 2) of the lid 10. This folding ladder 13 is one long ladder divided into three parts in the length direction into an upper ladder part 14, a middle ladder part 15 and a lower ladder part 16. One end of the upper ladder part 14 is a base of the back surface of the lid 10. Left and right plate-shaped upper ladder mounting members 19, 19 (1
(Only one is shown), and the other end is provided with a pair of left and right plate-shaped lower ladder mounting members 20 and 20 (only one is shown) as a supporting member on the left and right sides on the front end side of the lid 10. The upper ladder portion 14 is mounted and fixed via the lid 10
Is arranged in parallel with the back surface of the vehicle and a predetermined space is provided therebetween.

One end of the middle ladder 15 is rotatably connected to the other end of the upper ladder 14 through a pair of left and right hinges 22, 22 (only one is shown). Each of the hinges 22 has two pieces 2 as shown in the enlarged detail of FIG.
3, 24 are rotatably connected by a shaft 25, one piece 23 of which is at the end of the vertical frame 14a of the upper ladder portion 14, and the other piece 24 is of the vertical frame 15a of the middle ladder portion 15. It is attached and fixed to each end.

At the other end of the middle ladder portion 15, one end of the lower ladder portion 16 has a pair of left and right hinges 26 similar to the above.
It is rotatably connected via 26 (only one is shown). When the folding ladder 13 is folded, the folding ladder 13 shown in FIG.
As shown in, with respect to the back side of the lid 10 in the closed state,
Above the upper ladder portion 14 parallel to the lid 10, the middle ladder portion 15 is provided.
However, the lower ladder portion 16 is then stored in the ceiling opening portion 3 in a state of being folded into a substantially N shape by the hinges 22 and 26 so that the lower ladder portions 16 are overlapped in parallel.

A belt insertion hole 28 is formed through the upper and lower left and right ends of the plate 5a on the lid mounting side of the frame 5, that is, the frame 5 above the base mounting portion of the lid 10.
Further, brackets 29, 29 are fixedly mounted on the both surfaces of the lid mounting side plate member 5a in the vicinity of the belt insertion holes 28, respectively. The brackets 29, 29 have guide pulleys as belt guide members at the same height position. 30, 30
Is rotatably mounted around a horizontal horizontal axis. That is, these guide pulleys 30, 30 are arranged directly above the hinge 11 of the lid 10.

The other end of the upper ladder portion 14 is attached to the lid 1
Left and right pair of lower ladder mounting members 20 and 2 fixed to 0
At 0 (supporting member), a rod-shaped belt fixing member 31 extending in the left-right direction is provided on the lower part of the lid tip side of the both ladder mounting members 20,
It is inserted and fixed over 20 spaces. At the left and right ends of the belt fixing member 31, the end portions of the endless flat belts 33, 33 (only one is shown) are looped and locked. The intermediate portion of each belt 33 is provided with a space between the upper ladder portion 14 and the rear surface of the lid 10 so that the intermediate portion of the belt 33 passes through a moving pulley 44 and a fixed pulley 40, which will be described later, and is almost always parallel to the lid 10. It extends toward the base end side, and is inserted in the belt insertion hole 28 in the plate member 5a of the frame body 5 in a state of being stretched between the guide pulleys 30, 30 on both sides thereof.

Further, left and right belt winding pulleys 35, 35 (only one is shown) are arranged and housed in the motor housing chamber 7 of the frame 5 in correspondence with the guide pulleys 30, 30, respectively. The two take-up pulleys 35, 35 are drivingly connected to one electric motor 36 capable of forward and reverse rotations via a speed reducing mechanism (not shown) such as a worm gear. The motor 36, the speed reduction mechanism, and the two take-up pulleys 35, 35 constitute a belt take-up device 37 that can take out and take up the belt 33 at the base end side. The two take-up pulleys 35, 35 are synchronously rotated to take-up or take-out each belt 33 at the base end side, and each belt 33 is taken up by the take-up pulley 35 by the reverse rotation of the motor 36, for example.
Belt fixing member 31 (tip of belt 33) from 0, 30
While the belt length up to the above is shortened, each belt 33 is unwound from the take-up pulley 35 by the forward rotation of the motor 36 to extend the belt length.

In this embodiment, the moving pulley 44
Is stopped at the tip position of the guide groove 42 described below, the lid 1 is wound by the winding and unwinding operations of the belts 33, 33 by the two winding pulleys 35, 35 of the belt winding device 37.
0 is rotated between a closed position and an open position to open and close, and when each belt 33 is wound by the belt winding device 37, the belt fixing member 3 is pulled from the guide pulleys 30, 30.
By shortening the belt length up to 1 (strictly described below, fixed pulley 40), the lid 10 is closed in a horizontal posture as shown in FIG.
When the cover 10 is extended from the above position, the length of the belt is increased to open the lid 10 in an inclined posture as shown in FIG.

As shown in detail in FIG. 5, the belt fixing member 3 is attached to the pair of left and right lower ladder attaching members 20, 20.
A fixed pulley shaft 39 extending in the left-right direction at a position corresponding to the length direction of 1 and the lid 10 (a position directly above the belt fixing member 31 in the closed state) is rotatable between both ladder attachment members 20, 20. The fixed pulley shaft 39 is inserted into and supported by the fixed pulley 4 on both left and right sides in correspondence with the position of the belt 33.
0, 40 (only one shown) are attached.
That is, each of the fixed pulleys 40 is axially supported on the rear surface of the front end portion of the lid 10 so as to be immovable in correspondence with the belt fixing member 31.

Further, each lower ladder mounting member 20 has a lid 10 more than the fixed pulley 40 (belt fixing member 31).
A guide hole 42 (which may be a guide groove formed of a concave groove) as a guide portion extending substantially in the base end side of the lid 10 substantially parallel to the guide hole 42 of the opposing ladder mounting member 20 is formed. . As shown in FIG. 5, the guide hole 42 extends parallel to the base end side of the lid 10 along the lid 10 from the tip position between the belt fixing member 31 and the fixed pulley shaft 39, and the other end side portion. Then, after bending so as to approach the rear surface of the lid 10, the base end position is reached. In the guide hole 42, a movable pulley shaft 43 extending in the left-right direction across both the ladder mounting members 20 is slidably supported, and the left and right sides of the movable pulley shaft 43 are positioned at the position of the belt 33. Correspondingly, moving pulleys 44, 44 are attached. That is, each moving pulley 44 has a guide hole 42.
On the other hand, it is movably supported along the guide hole 42 via the movable pulley shaft 43.

The ends of the moving pulley shafts 43, which are the shafts of the moving pulleys 44, project outside the respective ladder mounting members 20 (opposite to the opposing ladder mounting members 20) by a predetermined dimension, and the projecting portions thereof project into the projecting portions. First link material 46, 46, respectively
One end (only one is shown) is rotatably connected. The other end portion of each of the first link members 46 is an end portion of the folding ladder 13 on the side of the upper ladder portion 14 in the middle ladder portion 15, more specifically, the middle step of the hinge 22 connecting the upper and middle ladder portions 14 and 15 to each other. A bracket 47 integrally attached to the piece 24 on the ladder portion 15 side is rotatably connected via a connecting shaft 48.

Then, as shown in FIG. 5, a belt 33 between the guide pulleys 30, 30 and the belt fixing member 31.
The intermediate portion of the lower side of the fixed and movable pulleys 40, 44 is moved to the movable pulley 44 as it goes from the belt fixing member 31 side (the tip side of the belt 33) toward the belt winding device 37 side (the proximal end side). After being wound from the side and bent to the fixed pulley 40 side at the base end side of the lid (right side in FIG. 5), that is, the tip end side of the lid (left side in FIG. 5), the fixed pulley 40 is wound from below and The belt winding device 37 is wound around the base end side of the lid 10 so as to bend at the tip end side of the lid, and when the lid 10 is positioned at the open position and is opened in the inclined posture.
By the winding and unwinding operations of each belt 33 by the moving pulley 44, the moving pulley shaft 43 moves the moving pulley 44 along the guide hole 42 of the lower ladder mounting member 20, and the moving pulley 44 moves to move the first link member. The middle ladder portion 15 is rotated together with the lower ladder portion 16 via a shaft 46 about a shaft 25 of a hinge 22 which is a connection point with the upper ladder portion 14.

A plate-like bracket 50 extending upward is provided at the tip of the lid 10, specifically, at the tip of the right lower ladder mounting member 20 at the tip of the lid. Are fixed integrally by 51, ... At one end of the bracket 50, one end of the second link member 52 is rotatably supported by a connecting shaft 53 extending in the left-right direction. The other end of the second link member 52 is rotatably connected to a connecting member 54 attached near the middle ladder 15 in the middle of the lower ladder 16 via a horizontal connecting shaft 55. As shown in FIG. 3, when the folding ladder 13 is extended with the lid 10 open, the opening angle due to the weight of the lower ladder portion 16 is adjusted by the second link member 52.

Further, the second link member 52 is extended to one end side thereof by a predetermined dimension, and the engaging pin 5 is provided at the extension portion thereof.
7 are protruded. A base end of a lever member 58 is rotatably supported by a connecting shaft 53 that supports one end of the second link member 52 on the bracket 50, and the base end of the lever member 58 has a connecting shaft 53. Arc hole 59 centered on
(A circular arc groove composed of a concave groove may be formed), and the engaging pin 57 is slidably engaged with the circular arc hole 59, so that the folding ladder 13 is in a folded state and the lever member 58 is When rotating in the counterclockwise direction in FIG. 5, the engagement pin 57 engages with one end (the left end in the figure) of the arc hole 59,
The base end of the lever member 58 is pivotally connected to the end of the second link member 52 on the tip side of the lid.

Further, a tension spring 62 as a biasing means is provided between the tip of the lever member 58 and a spring stopper member 60 attached to an intermediate portion of the lower ladder portion 16 integrated with the lid 10.
Is extended, and this spring 62 causes the lever member 5 to
8 is folded and urged in the counterclockwise direction in FIG. 5 so that the ladder 13 is extended.

Reference numeral 63 is a middle portion of the frame body 5 in the longitudinal direction and the lid 1.
0 is a link mechanism that is installed between the back surface of 0 and an intermediate portion in the longitudinal direction and that connects two links 64 and 65. In the direction in which the link 65 on the lid side extends the link mechanism 63 by a spring (not shown). The link mechanism 63 is biased and the lid 1
Adjust the 0 open position.

Further, 66 is a lock device provided on the plate member 5a on the tip side of the lid of the frame body 5, and locks and holds the lid 10 when it is in the closed position.

Next, the handling operation of the folding ladder device of the above embodiment will be described. First, when the folding ladder device is not used and the ladder 13 is folded, as shown in FIG. 1, the lid 10 closes the ceiling opening 3, and the ladder 13 is provided on the back side (upper side) thereof. Is housed. In this closed state, the base end portions of the left and right belts 33, 33 are wound around the belt winding device 37 and pulled,
The belt length from the guide pulleys 30, 30 to the fixed pulley 40 is short. In other words, each belt 3
The middle part of 3 is wound around the guide pulleys 30 and 30,
Since the guide pulleys 30, 30 are arranged in the frame body 5 above the position of the hinge 11 to which the base end of the lid 10 is attached, the height difference between the guide pulleys 30, 30 and the hinge 11 is different. Thus, the lid 10 is held in the closed position by the lock device 66 in a state in which the tip end portion is suspended by the belt 33.

The intermediate portion of each belt 33 on the tip side is fixed to the fixed pulley 40 and the movable pulley 44 on the base side of the lid of the movable pulley 44 from the front side of the belt 33 toward the base side. Since the fixed pulley 40 is bent so as to bend toward the base end side of the lid 10 after being bent toward the 40 side, each winding pulley 3 of the belt winding device 37 is bent.
5 when the belt 33 is pulled by the moving pulley 4
4 (moving pulley shaft 43) is pulled toward the tip side of the lid by the spans of both sides of the belt 33 wound around it, and is positioned at the tip position of the guide hole 42 in the lower ladder attachment member 20.

When the lid 10 is opened from this closed state, after the lock of the closed state by the locking device 66 is released, the motor 36 of the belt winding device 37 is rotated in the normal direction, for example. 33 is rolled out. Since the tensile force of the belt 33 decreases as the belt 33 is unwound from the winding pulley 35, the lid 10 pivots counterclockwise in FIG. 1 around the hinge 11 at the base end thereof to open. The belts 33 extend from the belt winding device 37 while being guided by the guide pulleys 30, 30 in accordance with the opening operation.

Then, as shown in FIG. 2, when the lid 10 is rotated with the ceiling 1 to a predetermined angle θ and reaches the open position in which the tip end thereof is slanted down, the lid 10 is linked. Is stopped and held in the open position by.

Even after the lid 10 is positioned at the open position in this way, the belt 33 is continuously paid out from each winding pulley 35. By feeding the belt 33,
The belt 33 can move to the moving pulley 44 side while rotating through the fixed pulley 40, the pulling force of the belt 33 pulling the moving pulley 44 becomes small, and the moving pulley 44 is guided to the guide hole 42. Along with this, it becomes possible to move to the base end position side.

At this time, when the lid 10 is moved to the open position, the center of gravity of the portion where the middle and lower ladder portions 15 and 16 are combined has the hinge 22 that connects the upper ladder portion 14 and the middle ladder portion 15. Since it is closer to the lid 10 than the vertical plane passing through the shaft 25, the middle and lower ladder portions 15 and 16 cannot be opened in the extension direction as they are.

However, one end of the second link member 52 is pivotally supported by the lower ladder mounting member 20 on the right side located on the rear surface of the tip of the lid 10, and the other end of the second link member 52 has the other end.
The lower ladder portion 16 is rotatably connected to an intermediate connecting member 54, and the base end portion of the lever member 58 is connected to one end portion of the arc hole 59 with respect to the end portion of the second link member 52 on the tip end side of the lid. Is integrally pivoted by the engagement of the engagement pin 57 of
The lever member 58 is rotationally biased by the biasing force of the tension spring 62 so that the folding ladder 13 is extended, while the movable pulley shaft 4 supporting the movable pulley 44.
3 is connected to one end of the first link member 46.
The other end of the link member 46 is the middle ladder portion 1 of the folding ladder 13.
5 is connected to a bracket 47 at the end portion of the upper ladder portion 14 side. Therefore, from these structures, the rotational biasing force of the lever member 58 by the tension spring 62 acts on the moving pulley 44 via the first link member 46, and the moving pulley 44 is closed along the guide hole 42. It is urged in the direction toward the base end. Then, when the tensile force of the belt 33 becomes smaller than the rotational biasing force of the lever member 58 by the tension spring 62, the middle ladder portion 15 rotates around the hinge 22 together with the lower ladder portion 16, and Ladder part 15, 16
The center of gravity of the lid 1 against the vertical plane passing through the axis 25 of the hinge 22
Move to the opposite side of 0. Further, upon receiving the rotational biasing force of the lever member 58, the moving pulley 44 starts to move to the base end position side along the guide hole 42.

That is, when the middle and lower ladder portions 15 and 16 are opened with the lid open, even if the center of gravity of the ladder portions 15 and 16 remains on the lid 10 side, the lever spring 58 is rotated by the tension spring 62. Due to the biasing force, the center of gravity of the ladder 13 can be smoothly and quickly moved away from the lid 10, and the extension operation of the ladder 13 in the opened state can be automatically started.

After the movement of the center of gravity, the ladder portions 15 and 16 try to open in the extension direction due to their own weight.
Therefore, the moving pulley 44 receives the turning biasing force of the lever member 58 by the tension spring 62, and subsequently receives the turning biasing force of the middle and lower ladder portions 15 and 16 by its own weight, and moves along the guide hole 42. It moves to the end position side, so that as shown in FIG.
Rotation in the extension direction is continued. Then, as shown in FIG. 4, the middle and lower ladder portions 15 and 16 are connected to the upper ladder portion 1.
When the ladder 13 is rotated so as to be aligned with 4, and the lower end of the ladder 13 is in contact with the floor surface, the moving pulley 44 is positioned at the base end position of the guide hole 42, and in this state, The motor 36 of the winding device 37 stops, the feeding of the belt 33 from the winding pulley 35 stops, and the ladder 13 is held in the extended state.

At this time, one end of the second link member 52 is pivotally supported by the lower ladder mounting member 20 on the right side located on the rear surface of the end of the lid 10, and the other end of the second link member 52 is a folding ladder. Connecting member 5 in the middle part of the lower ladder part 16 of 13
4 is rotatably connected to the upper ladder portion 14 and the lower ladder portion 1 that are fixed to the lid 10 at the ladder 13.
6 is connected to the middle ladder portion 15, and the middle portion of the lower ladder portion 16 and the tip portion of the lid 10 are connected to the second link member 5.
It is connected by 2. Therefore, when the ladder 13 is extended with the lid open, the middle and lower ladder parts 15, 16 are
Is a hinge 22 that connects the upper and middle ladder portions 14 and 15, a hinge 26 that connects the middle and lower ladder portions 15 and 16, and a connecting shaft 55 that connects the lower ladder portion 16 and the second link member 52. Then, the second link member 52 rotates like a magic hand while maintaining a substantially parallelogram having the four positions of the connecting shaft 53, which is a connecting portion of the second link member 52 to the tip portion of the lid 10, as vertices. Therefore, the lower ladder portion 16 is stably rotated with respect to the middle ladder portion 15 and its opening angle is regulated, and the lower ladder portion 16 is suddenly opened to hit the user's head or pinch a finger. Such problems will not occur.

On the other hand, after the ladder device is used, when the extended ladder 13 shown in FIG. 5 is folded and accommodated in the ceiling opening portion 3, the motor 36 of the belt winding device 37 is used.
For example, the belt 33 is reversed and the belt 33 is wound around each winding pulley 35. With this winding, the moving pulley 44 at the base end position of the guide hole 42 is pulled from the fixed pulley 40 and the belt fixing member 31 to the tip side of the lid by the belt 33, and the moving pulley 44 moves along the guide hole 42. Move from the base position to the tip position. This moving pulley 4
By the movement of 4, the first link member 46, the end portion of which is connected to the moving pulley 44, is changed in the clockwise direction in the drawing to push up the end portion of the middle ladder portion 15 on the upper ladder portion 14 side, and the middle portion thereof. The ladder portion 15 is rotated around the hinge 22 so that the ladder portion 15 faces the upper ladder portion 14, and the lower ladder portion 16 rotates around the hinge 26 so that the ladder portion 15 faces the middle ladder portion 15.
The folding of 3 starts (state of FIG. 3). Then, when the movable pulley 44 reaches the tip position of the guide hole 42, the initial state immediately after opening the lid is restored, and the folding ladder 13 is folded into a substantially N-shape (state in FIG. 2).

Even after the ladder 13 is folded, the belt 33 is continuously wound by the belt winding device 37.
Then, when the movable pulley 44 reaches the tip position of the guide hole 42, the movable pulley 44 cannot move further, so that the movable pulley 44 functions as a mere pulley for direction change, and the fixed pulley 40 in the belt 33. The part from to the tip is locked. Therefore, with the winding of the belt 33 by the winding device 37, the tip of the lid 10 whose tip is fixed by the belt fixing member 31 is pulled toward the guide pulley 30, and the guide pulleys 30, 30 While the fixed pulley 40, that is, the belt length to the tip of the lid 10, is shortened, the tip of the lid 10 is pulled up and the lid 10 is rotated in the closing direction.
When is rotated to the closed position, the winding of the belt 33 by the belt winding device 37 is stopped, and the lid 10 is stopped and held at the closed position. As a result, the ceiling opening 3 is closed, and the ladder 13 is accommodated in the folded state on the back side (upper side) of the lid 10 (state of FIG. 1).

In this embodiment, the belt winding device 37 is attached to the frame 5 inside the ceiling opening 3, that is, to the ceiling 1 side, and the belt 33 is wound around each winding pulley 35 of the belt winding device 37. , The belt fixing member 31 near the tip of the lid 10 is pulled, the lid 10 is pulled up and closed against the weight of the folding ladder 13 and the lid 10, and when the lid 10 is opened and lowered, the folding ladder 13 and the lid 10 are closed. Since the belt 33 may be unwound from the belt winding device 37 by its own weight, the load acting on the hinge 11 of the lid 10 is extremely small and its durability can be secured, and the belt 33 can be unwound or wound by the belt winding device 37. The lid 10 can be opened and closed smoothly according to the speed of taking.

Moreover, even when the ladder 13 expands and contracts when the lid 10 is opened, the hinge 11 of the lid 10 is less burdened, and the durability can be further ensured, and the belt 33 can be wound up. Also, the ladder 13 can be smoothly expanded and contracted in accordance with each feeding speed.

The upper ladder portion 14 of the ladder 13 is the lid 10
The belt 33 is attached to the back surface of the cover 10 with a space therebetween, and the belt 33 is fixed between the upper ladder portion 14 and the back surface of the lid 10 so that the belt 33 is almost always parallel to the lid 10.
Since the belt 33 is stretched between the belt 33 and the belt 30, the belt 33 is hidden behind the upper ladder portion 14, a sufficient arrangement space can be secured, and the appearance of the ladder 13 can be improved.

In the above embodiment, the movable pulley 44 is moved from the tip end position of the guide hole 42 to the base end position side to extend the ladder 13 after the lid 10 is opened. It is also possible to move 44 while the lid 10 reaches the open position so that the middle ladder portion 15 stands up.

It is also possible to connect springs to the middle and lower ladder portions 15 and 16 so that the ladder portions 15 and 16 are urged to rotate in the extension direction by the springs.

[0060]

As described above, according to the invention of claim 1, the frame body is fixed around the ceiling opening portion of the room, and the lid for opening and closing the ceiling opening portion is rotated at the base end portion of the frame body. It is movably attached to this lid, and the folding ladder that connects the upper, middle and lower ladders to each other so that they can be folded into a substantially N-shape is fixed at the upper ladder and each ladder is stored when the ladder is stored. For a folding ladder device that is stored in the ceiling opening in a folded state, attach the end of a belt member with an end to the tip of the lid and fix the belt member above the base attachment part of the lid. After hanging on the belt guide member located in the frame of
By connecting the base end portion to the belt winding means, the belt winding means as a drive device for opening and closing the lid is attached to the ceiling side of the building, and the belt member is wound and fed by the belt winding means. The lid can be opened and closed by the operation, the load acting on the connecting portion to the frame body on the base end side of the lid can be significantly reduced, the durability thereof can be improved, and the belt winding means can It is possible to smooth the opening / closing operation of the lid by adjusting the feeding or winding speed of the belt member.

According to the second aspect of the present invention, at the tip of the lid, there is provided a fixed pulley arranged corresponding to the belt fixing portion, and a guide portion extending along the lid on the base end side of the lid with respect to the fixed pulley. A support member is provided, and a movable pulley that is movable along the guide portion of the support member is provided. One end of the first link member is connected to this movable pulley, and the other end is located on the upper ladder portion side of the middle ladder portion. The belt member is connected to an end portion, and the belt member is wound around a moving pulley from a portion fixed to the lid toward a winding means side and then wound around a fixed pulley. The moving pulley is moved along the guide portion by the winding and unwinding operations, and the middle ladder portion is rotated around the connection point with the upper ladder portion via the first link member. Therefore, according to the present invention, the load on the connecting portion of the lid to the frame body can be reduced when the ladder is expanded and contracted in the opened state, and the durability thereof can be further improved.
It is also possible to expand and contract the ladder according to the respective speeds of winding and unwinding the belt member so that the expansion and contraction operation of the ladder can be smoothed.

According to the third aspect of the present invention, by connecting the front end of the lid and the intermediate portion of the lower ladder portion of the ladder with the second link member, when the ladder is expanded and contracted in the open state, The opening angle of the lower ladder portion can be regulated by rotating the lower ladder portion and the second link member while maintaining the substantially parallelogram, and the opening / closing operation of the lower ladder portion can be stabilized.

According to the fourth aspect of the present invention, the lever member is connected to the shaft portion of the second link member on the tip side of the lid so as to rotate integrally, and the lever member is rotationally biased so that the folding ladder is extended. By providing the biasing means, it is possible to quickly move the center of gravity of the middle and lower ladder sections when the lid is opened to move away from the lid, thereby automating and smoothing the extension operation of the ladder. You can

[Brief description of drawings]

FIG. 1 is a side view showing a stored state of a ladder according to an embodiment of the present invention.

FIG. 2 is a side view showing a state in which a lid is opened.

FIG. 3 is a side view showing an extension operation state of middle and lower ladder sections.

FIG. 4 is a side view showing a state where the ladder is extended.

FIG. 5 is an enlarged side view showing the mechanism at the tip of the lid.

[Explanation of symbols]

 1 Ceiling 3 Opening 5 Frame 10 Lid 11 Hinge 13 Folding Ladder 14 Upper Ladder 15 Upper Ladder 15 Middle Ladder 16 Lower Ladder 20 Ladder Mounting Member (Supporting Member) 30 Guide Pulley (Belt Guide Member) 31 Belt Fixing Member 33 Belt 35 Belt take-up pulley 36 Motor 37 Belt take-up device (belt take-up means) 39 Fixed pulley shaft 40 Fixed pulley 42 Guide hole (guide portion) 43 Moving pulley shaft 44 Moving pulley 46 First link member 52 Second link member 58 Lever Member 61 Tension spring (biasing means)

Claims (4)

[Claims] 1. A frame body which is arranged around and fixed to a ceiling opening of a room, a lid whose base end is rotatably attached to the frame body, and which opens and closes the ceiling opening, and a back surface of the lid. Upper ladder part fixed to the middle ladder part, one end of which is rotatably connected to the end part of the upper ladder part on the tip side of the lid, and one end part of which is rotatable to the other end part of the middle ladder part A folding ladder device comprising: a lower ladder portion connected to the lower ladder portion, which is stored in the ceiling opening in a state where each of the ladder portions is folded into a substantially N-shape when stored. A belt fixing portion provided, a belt guide member provided on the frame body above the base end attaching portion of the lid, a tip is attached and fixed to the belt fixing portion, and an intermediate portion is hooked on the belt guide portion. It is provided on the passed end belt member and the frame near the attachment part of the lid. And a belt winding means capable of winding and unwinding the belt member at a base end side, and configured to open and close the lid by a winding and unwinding operation of the belt member by the belt winding means. And folding ladder device. 2. The folding ladder device according to claim 1, wherein a fixed pulley that is immovably supported by a belt fixing portion at a tip portion of the lid, and a fixed pulley that is provided at a tip portion of the lid. Also, a supporting member having a guide portion extending substantially parallel to the lid on the base end side of the lid, a movable pulley movably supported by the guide portion of the supporting member, and one end of the movable pulley on the shaft portion of the movable pulley. The belt member is rotatably connected, and the other end is rotatably connected to an end portion of the middle ladder portion on the upper ladder portion side. It is hung over both pulleys so that the base end side of the lid of the moving pulley is bent toward the fixed pulley side toward the winding means side, and then the tip end side of the fixed pulley is bent toward the base end side of the lid. With the belt open, wind the belt member with the belt winding means. It is configured to move the moving pulley along the guide portion of the support member by the picking and feeding operation and rotate the middle ladder portion around the connection point with the upper ladder portion via the first link member. Folding ladder device characterized by. 3. The folding ladder device according to claim 1, wherein one end of the folding ladder device is rotatably supported by the tip of the lid, and the other end of the folding ladder device is rotatable by an intermediate part of the lower ladder part. A folding ladder device, characterized in that it is provided with a second link member that is connected and that adjusts the opening angle with the middle ladder portion of the lower ladder portion. 4. The folding ladder device according to claim 3, wherein a base end portion of the lever member is pivotally connected to a shaft portion of the second link member on the tip end side of the lid, and the lever member is connected to the tip end portion of the lever member. And a biasing device for biasing the lever member so as to extend the folding ladder, the folding ladder device.