JPH0454020B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a storage ladder that is installed on the ceiling of a building and used to climb up to the ceiling space.

In conventional storage ladders of this kind, one end of the ladder is pivotally connected to the edge of an opening in the ceiling so that the other end of the ladder can be moved up and down, and a bracket provided on the ladder A device in which a gas spring is provided between the openings is known (see Utility Model Application No. 150139/1983).
However, in this configuration, in order to prevent the ladder from floating in the lowest position, the fulcrum position of the spring is set so that no spring force is applied when the ladder is in the lowest position. Therefore, when descending the ladder, the operator must support the entire weight of the ladder with his hands at the last moment, which has the disadvantage that it is heavy and difficult for women and women to operate.

Further, in the above configuration, when lifting the ladder, the spring force does not work at first, and since it is dangerous if the load suddenly changes during the climb and becomes heavy, the spring force is weakened. Therefore, there is a drawback that if the latch piece comes off when the ladder is in its highest position, the ladder will descend. It is also possible to increase the spring force at the top of the ladder, but if this is strengthened, the balance change point of the spring force may be slightly lower than the top of the ladder. In that case, when lowering the ladder, if you pull it down too hard,
There was a risk that the ladder would suddenly fall from an upper position and injure the operator, and it was difficult to adjust the ladder.

Therefore, the present invention attempts to eliminate the above-mentioned drawbacks by connecting a compression spring that runs along the side edge of the opening when the ladder is in its lowest state, between the top end of the ladder and the ceiling, and compressing the spring from the handrail of the ladder. It is an object of the present invention to provide a storage ladder that can increase safety by moving the springs away. Further, the present invention is configured such that a downward rotational moment acts on the ladder when the ladder is in the lowest position, and an upward rotational moment is applied to the ladder when the ladder is in the highest position. It is an object of the present invention to provide a storage ladder which can be easily operated and which can prevent the ladder from falling and improve safety.

The drawings showing the embodiments of the present application will be described below. In Figure 1, 1 is the floor of the building, 2 is the ceiling,
3 is a roof, 4 is a living space, and 5 is a ceiling space, and this ceiling space 5 is partitioned from the living space 4 by the ceiling 2. The ceiling 2 is constructed as shown in FIGS. 2, 4, and 5. In this ceiling 2, 6 is a ceiling plate, 7 is a ceiling floor plate, and opening holes 6a, 7a are formed in opposing positions in these. Reference numeral 8 denotes a frame material fixed to the ceiling plate 6 along the edge of the opening hole 6a, and reference numeral 9 denotes an opening frame fitted into the opening holes 6a and 7a, and an engaging fitting 10 fixed to the outer peripheral surface.
is placed on and fixed to the frame member 8. This opening frame 9 forms a rectangular opening 11. Next, reference numeral 12 denotes a ladder mounting plate, one end of which is rotatably pivoted to the end frame 9a of the opening frame 9 via a hinge 13, as shown in FIG. Therefore, it is constructed so that it can be hung on and removed from the end frame 9c of the opening frame 9. This ladder mounting plate 12 also serves as a closing plate for the opening 11,
Its planar shape is formed to approximately match the opening 11, and in the stored state in which it is latched to the opening frame 9 by the locking device, the opening 11 is closed as shown in FIGS. 4 and 6. It's getting old. Further, the lower surface of the ladder mounting plate 12 has the same pattern and the same color as the lower surface of the ceiling plate 6, and forms a part of the ceiling plate 6 in the stored state, but is not necessarily limited to this. It's not a thing. 1
Reference numeral 4 denotes a connecting arm that is fixed to the upper surface of the end of the pivoting part of the ladder mounting plate 12 by means of a mounting bolt/nut 15, and as shown in FIGS. The left and right sides are arranged in a direction substantially perpendicular to the left side and the right side. A mounting arm 16 is also fixed to the upper surface of the free end of the ladder mounting plate 12 by a mounting bolt/nut 17, and is connected to the connecting arm 14.
There is one on the left and one on the right to correspond with each other. 1
A ladder 8 is attached to the connecting arm 14 and the mounting arm 16, and is constructed as shown in FIGS. 2 to 11. In this ladder 18, 19 is a first ladder element, 20 is a second ladder element, 21 is a third ladder element, and these first ladder element 19 and second ladder element 2
0 is connected to the second by a pair of left and right first connecting fittings 22.
The ladder element 20 and the third ladder element 21 are foldably connected by a pair of left and right second connecting fittings 23. As shown in FIGS. 2 and 4, the first ladder element 19 is composed of left and right side plates 24, 24 and a plurality of treads 25 mounted at equal intervals between these side plates 24, 24, The outer surfaces of the side plates 24, 24 are connected to the connecting arms 14, 14 and the mounting arms 16, 16.
They are fixedly attached to each other by mounting bolts and nuts 26 and 27, respectively. Note that the second ladder element 20 and the third ladder element 21 are also configured similarly to the first ladder element 19. The first connecting fitting 22 is constructed as shown in FIGS. 8 to 11. In this first connecting fitting 22, 28 is a connecting plate fixed to the side plate 24 of the first ladder element 19 with a mounting bolt/nut 29, and a spring hook part that doubles as a stopper by bending a part of the connecting plate. 30 is formed. 31 is a connecting plate fixed to the side plate 20a of the second ladder element 20 by a mounting bolt/nut 32; this connecting plate 31 and the connecting plate 28 are connected to the lower end of the first ladder element 19 and the second ladder element 20;
With the upper ends tightly abutting each other, the abutting surfaces and the upper surface of the first ladder element 19 are rotatably connected by a connecting pin 33 about a line that intersects with the upper surface of the first ladder element 19 . A locking pin 34 is provided on the connecting plate 31 in a protruding manner at a position apart from the connecting pin 33. Reference numeral 35 denotes a latch piece rotatably attached to the connecting plate 28 via a pivot 36, and a spring latch portion 37 is formed by bending a part of the latch piece. This latching piece 35 is a spring latching portion 30, 3.
8, the spring 38 tensioned between the springs 38 and 7 urges the spring 38 downwardly in FIG. At the tip of the locking piece 35, as shown in FIG. 10, there is an engagement groove 39 for locking the locking pin 34 when the first ladder element 19 and the second ladder element 20 are extended in a straight line; As shown in FIG. 9, a guide slope 40 is formed to guide the locking pin 34 into the engagement groove 39 during the process of stretching the second ladder element 20 relative to the first ladder element 19. Next, in the second connecting fitting 23, 41 is a connecting plate fixedly attached to the side plate of the second ladder element 20, 42 is a connecting plate fixedly attached to the side plate of the third ladder element 21, These connecting plates 41 and 42 are arranged so that the lower end of the second ladder element 20 and the upper end of the third ladder element 21 are brought into close contact with each other.
Connecting pin 43 centered on the line that intersects with the lower surface of
are rotatably connected by. Next, 44
is a handrail attached to the first ladder element 19;
As shown in FIG.
, and the other end is the side plate 2 of the first ladder element 19.
4, and are arranged in pairs on the left and on the right.

In FIG. 2, reference numeral 45 denotes a compression spring device for reducing the downward rotational moment due to the weight of the ladder 18, etc., which is constructed as shown in FIGS. 12 to 16, and is installed on both sides of the ladder 18. has been done. In this compression spring device 45, 46 is a gas spring exemplified as a compression spring, one end of which is connected to the distal end of the connecting arm 14, exemplified as a moving member, via a connector 47, and the other end, exemplified as a reference member. The opening frame 9 is connected to the middle portion of the side plate 9b via a connecting member 48. Note that a compression coil spring may be used as the compression spring. In the gas spring 46, 49 is a cylindrical cylinder body with one end closed, and 50 is a seal body fitted into the opening of the cylinder body 49, forming a rod hole 50a. 51 is a piston slidably fitted into the cylinder body 49;
A thin communication hole 52 is formed to communicate the left and right cylinder chambers 49a, 49b. A piston rod 53 is fitted into the rod hole 50a, and its tip end is connected to the piston 51. 54
is a damping spring fitted in the cylinder chamber 49a on the seal body 50 side. The cylinder chambers 49a, 4
Compressed gas is sealed in the interior of the piston rod 9b, and the gas pressure of the compressed gas applies a thrust force in the protruding direction to the piston rod 53. This thrust is generated by the difference in pressure receiving area on both sides of the piston 51.

Further, in FIG. 14, when the rod 53 moves to the left and enters the cylinder chamber 49, the cylinder chamber 49
The gas volume of the rod 9 decreases, the internal pressure increases, and the rightward thrust that causes the rod 53 to protrude increases.
In the connector 47, 55 is a connector screwed onto the piston rod 53, and as shown in FIG. 3, a spherical recess 55a is formed as a connector. Reference numeral 56 denotes a fastening elongated hole as a fastening part formed at the tip of the connecting arm 14, which is formed long in the direction intersecting the arc centered on the hinge 13 in FIG. The ladder 1 can be adjusted by connecting the gas spring 45 to any position of the hole.
The force (rotational moment M) for lifting the lower end of 8 can be adjusted. 57 is the spherical recess 5
5a rotatably fixed to the fastening elongated hole 56, and has a spherical portion 57a at one end.
is rotatably fitted into the spherical recess 55a with no slippage, and the shaft portion 57b at the other end is fitted into the fixing elongated hole 56, and the connecting arm 1 is secured by the collar portion 57c and the nut 58.
It is attached to 4. Further, in the connecting device 48, 59 is a connecting body fixed to the end of the cylinder body 49, and as shown in FIG. 12, a spherical recess 59a is formed as a connecting portion. Reference numeral 60 denotes a fastening hole as a fastening portion formed in the side frame 9b of the opening frame 9. Reference numeral 61 designates a connecting member for rotatably fixing the spherical recess 59a to the fixing hole 60, which is fitted into the fixing hole 60 and fixed with a nut 62 as shown in FIGS. 12 and 13. Fixing bolt 6
3, and a connector 64 that is screwed onto the upper surface of the bolt head 63a of this fixing bolt 63 eccentrically with respect to the axis of the fixing bolt 63, and a spherical part 64a at the tip of this connector 64 has the above-mentioned spherical shape. It is rotatably fitted into the recessed portion 59a so as not to come off. The above fixing bolt 63
A rotation operation part 65 is formed on the bolt head 63a to rotate the bolt head 63a with a spanner or the like. The amount of eccentricity of the connector 64 with respect to the axis of the fixing bolt 63 is determined when the fixing bolt 63 Due to the rotation of the gas spring 4 shown in FIG. 15c, the spherical recess 59a is
It is set to a size that allows it to be moved between the operating range of the stretching force shown in Fig. 6 and outside the operating range shown in Fig. 15a. Next, the position of the connector 47 between the gas spring 46 and the connecting arm 14 of the ladder 18 is set above the dead line connecting the connector 48 and the hinge 13 when the ladder 18 is lowered as shown in FIG. It is set to be located. This has the advantage that the thrust of the spring 46 always acts in the direction of lifting the ladder 18. Moreover, even if the protruding thrust of the spring 46 is large, the force (rotational moment M) that lifts the lower end of the ladder 18 is extremely small because the connecting member 47 is close to the dead line (see the 60 degree angle position in FIG. 16). . Furthermore, as the ladder 18 rises and approaches the state shown in FIG.
The position 7 moves far above the dead line, and the rotational moment M for lifting the lower end of the ladder 18 becomes very large, as can be seen from FIG.

Further, the magnitude of the thrust of the piston rod 53 in the gas spring 46 is as shown in FIG.
The upward rotational moment M around the pivot point of the ladder 18 due to the weight of the ladder 18 etc.
When the ladder 18 is in its highest state (downward inclination angle θ = 0 degrees), the upward rotational moment M caused by the gas spring 46 is smaller than the downward rotational moment m about the pivot point of the ladder 18. It is set to be larger than the downward rotational moment m due to its own weight. In the embodiment shown in FIG. 16, the magnitude relationship between the upward rotational moment M due to the gas spring 46 and the downward rotational moment m due to its own weight is reversed when the downward inclination angle θ of the ladder 18 is approximately 50 degrees. It's summery.

Next, 66 is the first ladder element 1 when the ladder 18 is used.
17 to 19, and are disposed on both sides of the ladder 18, respectively. In this support device 66, reference numeral 67 is a mounting bracket fixed to the upper surface of the middle part of the ladder mounting plate 12, and 66 is a mounting bracket whose lower end is connected to the connecting shaft 6.
The first hanging rod is rotatably connected by a first hanging rod 9, and a long hole 70 extending in the longitudinal direction thereof is formed at the upper end of the first hanging rod. This elongated hole 70 is formed in a direction perpendicular to the rotating surface of the first hanging rod 68. 7
1 is a mounting bracket fixed to the side frame 9b of the opening frame 9, and as shown in FIG.
and an intermediate connecting portion 71b. This projecting connecting portion 71b is configured to form a spring storage space 72 between the mounting portion 71a and the side frame 9b when the mounting portion 71a is attached to the side frame 9b. 73 is a second hanging rod whose upper end is rotatably connected to the overhanging connecting portion 71b by a connecting shaft 74;
A pin hole 75 that can overlap with the elongated hole 70 is formed at the lower end of this. 76 is the pin hole 75
A connecting pin serving as an engaging convex portion is fitted into the elongated hole 70 so as to be slidable in the longitudinal direction. Note that the engaging convex portion may be provided integrally with the second hanging rod 73. In addition, the long hole 70 is connected to the second hanging rod 73.
Alternatively, an engaging convex portion may be provided on the first hanging rod 68. 77
is a torsion spring fitted to the connecting shaft 74;
As shown in Figures 7 and 18, one end is attached to the mounting bracket 7.
1, the other end is hooked on the second hanging rod 73, and the second
The hanging rod 73 is biased clockwise in FIG. 19. The magnitude of this urging force is such that, at least in a state where the weight of the ladder 18 etc. is not applied to the second hanging rod 73, the second hanging rod 73 is rotated in the urging direction and the first hanging rod 68 and the second hanging rod 73 are It is set up in such a way that it can make people lose their minds. The mounting position of the mounting bracket 71 is as shown in FIG.
The ladder 18, the first hanging rod 68, and the second hanging rod 73 form a V-shape. The lengths of the first hanging rod 68 and the second hanging rod 73 are such that when the ladder 18 is raised to the highest level, the first hanging rod 68 and the second hanging rod 73 are in a state where the connecting pin 76 is fitted into the elongated hole 70. When the ladder 18 is bent and the ladder 18 is lowered to its lowest position, the connecting pin 76 comes into contact with the upper end of the elongated hole 70, and the first hanging rod 68 and the second hanging rod 73 are set in a straight line.

Next, reference numeral 78 denotes a locking device for removably locking the free end side portion of the ladder 18 to the end frame 9c of the opening frame 9, and is constructed as shown in FIGS. 20 to 23. In this locking device 78, 79
is a support bracket fixed to the end frame 9c;
As shown in FIG. 1, a flat mounting board 80 and a pair of support pieces 81, 81 fixed to this mounting board 80 are provided.
This mounting board 80 has mounting bolts and
It is fixed to the end frame 9c with nuts 82. 8
3 is a hanging rod installed between the support pieces 81, 81;
It is supported in a substantially horizontal direction. Reference numeral 84 denotes a device main body fixed to the upper surface of the free end of the ladder mounting plate 12, which is configured in a box shape with an open bottom, and has a storage space 85 inside. This device main body 84 is attached at a position corresponding to the above-mentioned hanging rod 83. Reference numeral 86 denotes an engagement groove formed in the upper part of the device main body 84, into which the above-mentioned locking rod 83 is fitted when the ladder mounting plate 12 is raised to the storage position. Reference numeral 87 denotes a flat plate-shaped locking member rotatably attached to the main body 84 of the device via a support shaft 88 on the side of the engagement groove 86, and a spring 89 stretched between it and the operating lever described later. 20, and comes into contact with a first stopper 90 fixed to the main body 84 of the device. The support shaft 88 is oriented horizontally, that is, parallel to the hanging rod 83, when the ladder 18 is in the stored state. In the locking member 87, 91 is a contact portion formed so as to be able to come into contact with the locking rod 83;
As shown in FIG. 22, when in contact with the first stopper 90, the ladder 18 is projected in a direction that intersects with the rotating direction of the ladder 18 and rotates upward by the spring 89, and the ladder 18 is in a lowered state. is located across the engagement groove 86. This contact portion 91 also serves as an engaging portion in the drawing. Reference numeral 92 denotes a locking pawl formed to be able to lock the locking rod 83 when the ladder 18 is raised to the storage position, and is projected in the upward rotation direction of the ladder 18 as shown in FIG. When the ladder 18 is in the lowered state, it is located outside the engagement groove 86. 93
is a fitting groove formed between the abutting portion 91 and the locking pawl 92, into which the locking rod 83 is fitted when the ladder 18 is in the stored state, as shown in FIG. 94 is a spring hanging part. Reference numeral 95 denotes an operating lever whose upper end is rotatably connected to the device main body 84 by a pivot 96, and whose lower end is attached to the ladder mounting plate 12.
The ladder mounting plate 1 is inserted through a through hole 97 formed in the ladder mounting plate 1.
It protrudes below 2. This operating lever 95
is the spring 89 stretched between the spring hanging part 94
is urged toward the support shaft 88 by the device main body 84.
The second stopper 99 is fixed to the second stopper 99. The position of the second stopper 99 changes when the operating lever 95 comes into contact with the second stopper 99 when the ladder 18 is in the stowed state.
5 is set to be inclined diagonally downward as shown in FIG. In the operating lever 95, reference numeral 100 denotes a rotation regulating portion, and the locking member 8
7 is formed so as to abut against the distal end surface of a contact portion (engaging portion) 91 in a state in which the first stopper 90 is in contact with the first stopper 90 . The rotation restricting portion 100 is activated by the locking member 87 by the force in the biasing direction of the operating lever 95.
It is formed at a position to apply a rotational moment in the direction of rotation. 101 is a locking stepped portion;
When the ladder 18 is in the stored state, it engages with the tip of the contact portion (engaging portion) 91 of the locking member 87 rotated by the locking rod 83 to lock the return rotation of the locking member 87. is formed. This locking step 101
When the operating lever 95 is in the diagonally downward state in contact with the second stopper 99, the tip of the contact portion 91 is sufficiently locked, and the operating lever 95 is moved downward from the diagonally downward state by an appropriate amount (directly downward in the drawing). It is formed so that it comes off from the tip of the abutment part 91 when it is rotated. Reference numeral 102 denotes a hooking hole as an operating part formed at the lower end of the operating lever 95, and the hook 105 at the tip of the operating rod 104 can be hooked thereto for operation, as shown in FIG. A third stopper 103 restricts rotation of the operating lever 95 in a direction opposite to the urging direction (direction of the support shaft 88), and is constituted by the edge of the through hole 97 in the drawing. This third stopper 103 is located at a position that allows rotation of the operating lever 95 for removing the abutment portion 91 from the locking step portion 101, and the rotation restriction portion 10
0 is in contact with the contact portion 91, it is arranged at a position close to the opposite side of the operating lever 95 from the spindle 88 side, and is adapted to almost completely restrict rotation of the operating lever 95. .

In the case of the above configuration, when the ladder 18 is not required, the first, second, and third ladder elements 19, 20, and 21 of the ladder 18 are connected to the first and second connections as shown in FIG. The ladder mounting plate 12 is held in the folded state by the metal fittings 22 and 23 at the highest position shown in FIG. 6, that is, the storage position. In this state, the ladder mounting plate 12 is tightly fitted into the opening 11 of the ceiling 2 and closes the opening 11, and the ladder 18 is attached to the ceiling space 5.
It will be hidden from view from living space 4. In addition, in this state, the upward rotational moment M of the ladder 18 due to the stretching force of the gas spring 46
As shown in FIG. 16, the downward rotational moment m of the ladder 18 due to the weight of the ladder 18, etc. is much larger, so the free end of the ladder 18 is lifted by the tension force of the gas spring 46. and securely held in the stowed position. Therefore,
Even if the locking device 78 fails due to some reason, for example, the spring 89 is damaged, and the locking bar 83 is disengaged by the locking claw 92, it is possible to prevent an accident in which the ladder 18 falls from the storage position. The safety of a storage ladder that is stored in two parts can be increased. Further, when the ladder 18 is stored as described above, the locking device 78
As shown in FIG. 2, the return rotation of the locking member 87 is prevented by the locking stepped portion 101 of the operating lever 96 when the locking rod 83 is fitted into the engaging groove 86 and the fitting groove 93. As a result, the free end of the ladder 18 is securely latched in the storage position, thereby preventing the ladder 18 from falling from the storage position even if the gas spring 46 fails for some reason, such as a gas leak. It can be prevented. Further, when the ladder 18 is in the stored state, the first hanging rod 68 of the support device 66
As shown in FIG. 6, the second hanging rod 73 is housed in the opening 11 in a bent state via the elongated hole 70 and the connecting pin 76.

Next, if you want to use the ladder 18, first remove the hook 10 of the operating rod 104 as shown in FIG. 23A.
The hook hole 1 of the operating lever 95 with 5 pointing diagonally downward
02, then pull the operating rod 104 to rotate the operating lever 95 against the force of the spring 89, and as shown in FIG.
1 and the contact portion 91 are disengaged. In this case, the engagement between the locking step 101 and the abutting portion 91 is disengaged by rotating the operating lever 95, which is tilted diagonally downward, at least to a position facing straight down. , the person operating the operating lever 95 can disengage the locking stepped portion 101 and the contact portion 91 by simply hooking the hook portion 105 of the operating rod 104 into the hooking hole 102 and pulling it downward with one hand. can. When the operating rod 104 is further pulled down after the engagement between the locking step portion 101 and the contact portion 91 is disengaged as described above, the locking member 8
7 is rotated by the force of the spring 89 and comes into contact with the first stopper 90, and at the same time, the abutting portion 91 pushes out the locking rod 83 from the fitting groove 93 and slightly pushes the free end of the ladder 18. Press down. Note that the upward rotational moment M of the ladder 18 due to the gas spring 46
is relatively small, the locking member 87 is immediately rotated back by the force of the spring 89 when the locking step portion 101 and the abutting portion 91 are disengaged. Next, the operating rod 104 is pulled downward to lower the free end of the ladder mounting plate 12 as shown in FIG. When the ladder mounting plate 12 is lowered in this manner, the first hanging rod 68 and the second hanging rod 73 of the support device 66 are stretched with a reduced bending angle. and ladder mounting plate 12
When the support device 66 is lowered to a position where the downward angle θ is approximately 60 degrees, the connecting pin 76 of the support device 66 comes into contact with the upper end of the elongated hole 70, and the first hanging rod 68 and the second hanging rod 73 are stretched in a straight line to prevent further downward rotation of the ladder mounting plate 12. Furthermore, as the ladder mounting plate 12 is lowered as described above, as shown in FIG. 16, the upward rotation moment M of the ladder 18 caused by the gas spring 46 decreases rapidly, whereas The downward rotational moment m gradually decreases, and the downward inclination angle θ of the ladder mounting plate 12
When the angle θ of the downward inclination of the ladder mounting plate 12 reaches approximately 50 degrees, the magnitude relationship of both moments M and m is reversed, and when the downward inclination angle θ of the ladder mounting plate 12 reaches approximately 60 degrees, the downward slope of the ladder 18 due to the weight of the ladder 18, etc. becomes approximately 60 degrees. The rotational moment m becomes larger than the upward rotational moment M of the ladder 18 caused by the gas spring 46. Therefore, simply by lowering the ladder mounting plate 12 to its lowest position as shown in FIG. 2, the ladder 18 is reliably held at its lowest position.
Further, when lowering the ladder 18 by pulling the operating rod 104 downward as described above, FIG.
As shown in FIG. 3C, the locking member 87 is rotated back by the force of the spring 89.
Since the rotation of the operating lever 95 is prevented by the contact portion 91 of the locking member 87 and the third stopper 103, the operating lever 95 can be prevented from rotating during operation, and the hook portion 105 of the operating rod 104 is prevented from rotating. It can be prevented from coming off from the hook hole 102. Next, the folded ladder 18 shown in FIG. 7 is stretched out into a straight line as shown in FIG. In this case, the first connecting fitting 22 of the ladder 18
, when the second ladder element 20 is extended with respect to the first ladder element 19, the latch pin 34 touches the guide slope 4 of the latch piece 35, as shown in FIGS. 9 and 10.
0 and rotates the locking piece 35 against the spring 38, and then engages with the engagement groove 39 of the locking piece 35 and is integrally coupled. Therefore, the first connecting fitting 2
Even if a large downward load is applied to the 2nd part, the 10th
As shown in the figure, the butted state of the first ladder element 19 and the second ladder element 20 can be maintained reliably. In addition, in the second connecting fitting 23, the connecting pin 43 is located on the lower surface of the ladder 18, so even if a large downward load is applied to the second connecting fitting 23, the second ladder element 20 and the third ladder element 21 can be reliably maintained. When the ladder 18 is extended as described above, the lower end of the third ladder element 21 comes into contact with the floor surface 1, as shown in FIG.
Use the ladder 18 in this state. In this case, the gas spring 46 is connected to the ceiling 2 as shown in FIG.
Since the gas spring 46 is disposed within the opening 11 and at a position not facing the ladder 18, the gas spring 46 does not get in the way when a person goes up or down the ladder 18. Also, when climbing ladder 18, ladder 1
A large downward load is applied to the ladder mounting plate 8, but as shown in FIG.
6, the load can be divided into two parts and supported by the support device 66 and the hinge 13, thereby making it possible to safely support a large load in terms of strength. Next, if you want to store the ladder 18 again, rotate the latching piece 35 of the first connecting fitting 22 on the ladder 18 against the spring 38 to remove the latching pin 34 from the engagement groove 39. The first, second and third ladder elements 19, 20, 21 are folded and superimposed on the ladder mounting plate 12. After that, the ladder mounting plate 12
Lift the free end of. In this case, the support device 66
In this case, when the ladder mounting plate 12 is lifted, the connecting pin 76 moves relatively within the elongated hole 70, thereby allowing the ladder mounting plate 12 to be lifted, and at the same time, the load of the ladder 18, etc. is transferred to the second hanging rod 73. As a result, the second hanging rod 73 is rotated clockwise as shown in FIG. 19 by the spring force of the torsion spring 77, and the first hanging rod 68 and the second hanging rod 73 are connected to the connecting pin. It can be bent using 76 as a fulcrum. Therefore, the ladder mounting plate 12 can subsequently be lifted up. Thereafter, when the ladder mounting plate 12 is rotated upward to a position where its downward inclination angle θ is smaller than about 50 degrees, as is clear from FIG. Since the downward rotational moment m of the ladder 18 due to its own weight is greater than the downward rotational moment m of the ladder 18, the ladder mounting plate 12 is then automatically rotated upward by the tension force of the gas spring 46 and is housed in the opening 11 of the ceiling 2. . Further, due to the upward rotation of the ladder mounting plate 12, the latching rod 83 is fitted into the engagement groove 86 of the locking device 78, and the abutting portion 91 abuts the latching rod 83 and resists the spring 89. It is rotated. The rotation of the contact portion 91 is stopped when the bottom of the engagement groove 86 comes into contact with the hanging rod 83, and at this point, as shown in FIG.
3 fits into the fitting groove 93 and is locked by the locking pawl 92, and the locking step portion 101 engages with the contact portion 91 to prevent the locking member 87 from rotating back. . Therefore, the ladder mounting plate 12 and the ladder 18 are completely housed within the opening 11 and are securely latched and held in this housed position. Note that when the stretching force of the gas spring 46 is relatively small, the upward rotation of the ladder mounting plate 12 is stopped when the abutting portion 91 abuts the latching rod 83, and the subsequent upward rotation of the ladder mounting plate 12 is stopped. The movement is performed by hooking the hook portion 105 of the operating rod 104 into the hooking hole 102 and pushing up the operating lever 95.
In this case, since the rotation of the operation lever 95 is restricted by the contact portion 91 and the third stopper 103 as described above, the ladder mounting plate 12 can be easily rotated upward by pushing up the operation lever 95. can be done.

Next, the case of assembling the compression spring device 45 will be explained. First, as shown in Figure 6, ladder 1
8 is stored in the storage position, and the tip of the connecting arm 14 is moved to a position where it is as far away from the fixing hole 60 of the side frame 9b as possible. In this state, the connector 57 of the connector 47 at one end of the gas spring 46, which is fully extended, is inserted into the fastening elongated hole 56 of the connecting arm 14 and fixed with a nut 58, as shown in FIG. . Further, the fixing bolt 63 of the coupling member 48 at the other end of the gas spring 46 is inserted into the fixing hole 60, and the nut 62 is screwed together. In this case, in the connector 48, a spherical recess 59 as a connector
When a is located on the side opposite to the connecting arm 14 with respect to the center of the fixing bolt 63, the spherical recess 59a is located in the damping area (including the non-operating area) of the gas spring 46, as shown in FIG. 15a. Therefore, the fixing bolt 63 can be easily fitted into the fixing hole 60 with little or no force exerted on the gas spring 46. After that, a spanner or the like is fitted to the rotation operation part 65 of the fixing bolt 63, so that the spherical recess 59a is located on the connecting arm 14 side with respect to the center of the fixing bolt 63, as shown in FIGS. Rotate the fixing bolt 63 as shown in FIG.
a is moved to the operating range of the expansion force of the gas spring 46. In this case, a large tensile force of the gas spring 46 is applied to the fixing bolt 63, but the fixing bolt 63
Since the fixing bolt 63 is rotated with a spanner or the like, the fixing bolt 63 can be rotated with a relatively small force. Thereafter, the nut 62 screwed onto the fixing bolt 63 is tightened to fix the rotation of the fixing bolt 63, and the assembly of the compression spring device 45 is thus completed. Figure 24,
FIG. 25 shows a different example of a compression spring, in which the damping spring 54 of the gas spring 46 in the above embodiment is omitted, and the damping region of the gas spring 46e is eliminated.

It should be noted that the same reference numerals as those in the previous figure are appended with an alphanumeric letter "e" for parts that are functionally the same or equivalent to those in the previous figure, and redundant explanations are omitted.
(Also, in the following figure, the same idea is given by alphanumeric characters f and g, and redundant explanations are omitted.) Fig. 26 shows a different example of the coupling of the compression spring device, and shows the mounting plate 106. A rotating arm 107 is pivotally attached to a hole (not shown) serving as a fixing part, and a hexagonal head 108 as a rotating operation part about the pivoting part is integrated with this rotating arm 107. Further, an arc-shaped elongated hole 109 is formed at the tip thereof. A rotation bolt 110 screwed onto the mounting plate 106 is inserted into this elongated hole 109, and the rotation arm 107 is fixed by this fixing bolt 110.
The rotation can be fixed. Further, a connecting body 59f provided at one end of the gas spring 46f is connected to the rotating arm 107. The rotating arm 107 and the fixing bolt 110 are a connecting member 61f.
When the rotating arm 107 rotates, the connecting body 5
9f can be moved into and out of the operating range of the gas spring 46f.

27 and 28 show another different embodiment of the compression spring device, in which a fastening body 111 as a fastening part is fixed to the side frame 9bg by a nut 112, and a connecting screw is attached to this fastening body 111. The bodies 113 are connected by connecting bolts 114. A female screw hole 113a is formed in this connecting screw body 113, and a male screw portion 115 as a connecting portion is formed in the female screw hole 113a at the tip of the piston rod 53g.
are screwed together. The piston rod 53g is configured to be rotatable.
A spanner hook part 116 is formed as a rotation operation part. A lock nut 117 is screwed into the male threaded portion 115, and the lock nut 117 and the connecting screw body 113 constitute a connecting member 61g.

In this embodiment, when assembling the compression spring 46g, first, as shown in FIG.
15 is largely inserted into the female threaded hole 113a, one end of the compression spring 46g is connected to the moving member (or the reference member), and the connecting screw body 113 at the other end of the compression spring 46g is connected to the reference member (or the moving member). ) is connected to the fastening body 111 with a connecting bolt 114. In this case, the amount of screw engagement between the female screw hole 113a and the male screw portion 115 is adjusted so that there is no need to apply a compressive force to the compression spring 46g. Thereafter, apply a spanner to the spanner hook part 116 to rotate the piston rod 53g, and as shown in FIG.
is relatively moved in the direction of coming out of the female threaded hole 113a, thereby causing the spring force of the compression spring 46g to act on the moving member and the reference member.

As described above, in the present invention, an opening 11 is provided in the ceiling 2 used to partition the living space 4 and the ceiling space 5 above it, and a ladder 18 is provided at one edge of the opening 11. One end is pivoted, and the ladder 1
The other end of the ladder 18 is configured so that it can be hung on and removed from the other edge of the opening 11, so when the ladder 18 is not in use, the free end of the ladder 18 can be hung on the edge of the opening 11. By keeping the ladder 18 in place, the ladder 18 can be stored in the opening 11 of the ceiling 2. This allows the living space 4 to be used effectively without being obstructed by the ladder 18. When the user wants to go up to the ceiling space 5, the user can easily go up to the ceiling space 5 using the ladder 18 by unlatching the ladder 18 and lowering the ladder 18.

Further, the ladder 18 is disposed in the opening 11 of the ceiling 2, one end of the ladder 18 is pivotally connected to one edge of the opening 11, and by lowering the ladder 18, the opening of the ceiling 2 is opened. 11 is opened, so when going up and down to the ceiling space 5 using the ladder 18, the person can go up and down to the ceiling space 5 through the opening 11 in the ceiling 2 that is opened by lowering the ladder 18. It has the convenience of being able to.

Further, at the end of the ladder 18 on the pivoting part side, a connecting arm 14 is provided which projects upward along the side edge of the opening 11.
A compression spring 4 is provided at the upper end of the connecting arm 14.
6 are connected to each other, and the other end of the compression spring 46 is connected to the connecting arm 1 at the side edge of the opening 11.
The spring force (stretching force) of the compression spring 46 is connected to the ladder 18 at a position closer to the hook than the upper end of the ladder 1
8 in the direction of rotating the ladder 18 upward, so when the free end of the ladder 18 is raised or lowered in order to use the ladder 18, the ladder 18 is rotated by its own weight. the ladder 18 by applying a rotational moment smaller than the downward rotational moment to the ladder 18.
This has the effect that the ladder 18 can be raised and lowered easily with little force.

Furthermore, the present invention is characterized in that the compression spring 46 provided between the connecting arm 14 and the opening is constructed as follows. In other words, ``The end of the ladder on the pivot point side is provided with a connecting arm that projects upward, and one end of a compression spring is connected to the spring attachment part provided at the upper end of the connecting arm. The other end of the compression spring is connected to the opening at a position closer to the hanging part of the ladder than the base of the connecting arm, and the height of the hanging part of the spring of the connecting arm is: In addition to the pivot point and the compression spring, so that even when the other end of the ladder is in its lowest position, a rotational moment about the pivot point of the ladder is generated in an upward direction that raises the other terminal of the ladder. The thrust of the compression spring is set so that it is located above the line connecting the end connection point, and the magnitude of the thrust of the compression spring is set so that when the ladder is in the lowest position, the compression spring causes an upward rotational moment about the pivot point of the ladder. is smaller than the downward rotation moment centered on the pivot point due to the ladder's own weight, and when the ladder is at its highest point, the upward rotation moment centered around the pivot point due to the compression spring is smaller than the downward rotation moment centered around the pivot point due to the ladder's own weight. What is the upward rotational moment centered on the pivot point of the ladder due to the compression spring, and the downward rotational moment centered on the pivot point of the ladder due to the ladder's own weight? The downward inclination angle of the ladder is approximately at the lowest point.
It is unique in that it is set so that it will look the same at 50 degrees. By having the above-mentioned characteristic configuration, the present invention maintains the elevated state of the ladder 18 with a large spring force even when the ladder 18 is in its highest state, and prevents the ladder 18 from falling even if the latching means is damaged. In addition, in the process of lowering the ladder 18, the ladder 18 is always subjected to a rotational moment that causes it to rise in most of the steps, so even women and girls can hang down and pull it down easily. There are also effects that can be manipulated. Furthermore, when the ladder 18 descends to about 50 degrees, which is near the lowest position, the vertical rotational moment is balanced and the ladder becomes weightless, making it possible for the operator to notice changes in gravity. This means that in order to prevent the ladder 18 from rising in the lowest position, a downward rotational moment must be applied to the ladder 18, but in order to do so, the accident that occurred with the prior art described above may occur. do. The present invention has the effect of preventing such accidents and providing ease of handling for the operator.

[Brief explanation of the drawing]

The drawings show an embodiment of the present application, and FIG. 1 is a side view showing how the storage ladder is used, FIG. 2 is an enlarged sectional view of the main part of the storage ladder, FIG. 3 is an enlarged sectional view taken along the line Figure 4 is a plan view of Figure 2, and Figure 5 is a plan view of Figure 2.
6 is a cross-sectional view showing the stowed state of the ladder with some parts omitted; FIG. 7 is a side view showing the ladder in the folded state; and FIG. 8 is a side view of the folded part of the ladder in the folded state. Figure 9 is a side view of the folded part of the ladder in the middle of being stretched, Figure 10 is a side view of the folded part of the ladder in the stretched state, Figure 11 is a sectional view taken along the - line, and Figure 12 is the connection of the compression spring. Fig. 13 is a front view of Fig. 12, Fig. 14 is a sectional view showing a gas spring as a compression spring, and Fig. 15 shows the extension force characteristics of the gas spring and the connection of the gas spring. An explanatory diagram showing the relationship between the function of the tool, FIG. 16 is a graph showing the relationship between the descending angle of the ladder and the rotational moment acting on the ladder, FIG. 17 is an enlarged cross-sectional view along the - line, and FIG. 18 is the -
19 is a side view showing the operating state of the first suspension rod and the second suspension rod, FIG. 20 is an enlarged sectional view of the locking device portion, FIG. 21 is a plan view of FIG. 20, and FIG. The figure is a cross-sectional view of the locking device part when the ladder is lowered, FIG. 23 is an explanatory diagram of the operation of the locking device, and FIG. 24 is a cross-sectional view showing different embodiments of the compression spring.
Fig. 25 is a graph showing the tension force characteristics of the compression spring shown in Fig. 24, Fig. 26 is a side view showing different embodiments of the compression spring coupling device, and Fig. 27 is a graph showing other different embodiments of the compression spring coupling device. FIG. 28 is a partially cutaway plan view showing the embodiment, and FIG. 28 is an explanatory diagram of the operation of the connector shown in FIG. 27. 2...Ceiling, 4...Living space, 5...Ceiling space, 11...Opening, 14...Connecting arm, 18...
Ladder, 46...Gas spring (compression spring).

Claims (1)

[Claims] 1. A ladder is installed in an opening in the ceiling that separates the living space in a building from the ceiling space above it, so as to cover the opening, and one end of the ladder is connected to one end of the opening. The other end of the ladder is configured to be able to be hooked onto and removed from a latching portion provided at a position away from the pivot portion in the opening. In a storage ladder that can be used for climbing from a living space to a ceiling space by unlatching the ladder and tilting the ladder, the end of the ladder on the pivoting part side is provided with a connecting arm projecting upward, and one end of a compression spring is connected to a spring attachment part provided at the upper end of the connecting arm,
The other end of the compression spring is connected to the opening at a position closer to the hanging part of the ladder than the base of the connecting arm, and the height of the hanging part of the spring of the connecting arm is:
In addition to the pivot point and the compression spring, so that even when the other end of the ladder is in its lowest position, a rotational moment about the pivot point of the ladder is generated in an upward direction that raises the other terminal of the ladder. The thrust of the compression spring is set so that it is located above the line connecting the end connection point, and the magnitude of the thrust of the compression spring is set so that when the ladder is in the lowest position, the compression spring causes an upward rotational moment about the pivot point of the ladder. is smaller than the downward rotational moment around the pivot point due to the ladder's own weight,
In the highest state of the ladder, the upward rotational moment around the pivot point of the ladder due to the compression spring is set to be larger than the downward rotational moment centered on the pivot point due to the ladder's own weight, and The upward rotational moment centered on the pivot point of the ladder and the downward rotational moment centered on the pivot point of the ladder due to the ladder's own weight are the same when the downward inclination angle of the ladder is approximately 50 degrees near the lowest position. A storage ladder characterized by being set so as to