JP7109817B2 - Expansion device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a telescoping device such as a telescoping support for a ladder or a stepladder.

For example, the expansion and contraction device for the strut of a stepladder is provided with a locking mechanism for inserting the insert into the mantle so as to be telescopic and for fixing the insert in the mantle at an expanded and contracted position. The lock mechanism is a support frame fixed to the mantle. and a lock member that is swingably pivoted to the support frame and engages with the engaged portion of the inserter, and a handle that swings the lock member away from the inserter. .

In this type of conventional telescoping device, the handle includes a pivot portion which supports a locking member and is supported through a pair of side wall portions of the support frame so as to be axially movable, and a pivot portion which is formed integrally with the pivot portion. The handle is supported by the support frame so as to be movable in a direction orthogonal to the swinging direction, and the handle is engaged with the side wall of the support frame. A locking hole is provided, and when the locking member locks the insert body, the locking part is locked in the locking hole by movement of the handle, thereby making the handle or the locking member unswiveable and locking the locking member. There is a device that prevents the separation swing (for example, Patent Document 1).

JP-A-2006-52581

However, in the conventional case, after the lock member is engaged with the insertion body by swinging the handle, it is necessary to move the handle in a direction perpendicular to the swinging direction so that the hooking portion is hooked in the hooking hole. Further, when the lock member is to be removed from the insertion body, the handle is first moved in a direction orthogonal to the swinging direction to release the hooking of the hooking portion from the hooking hole, and then the handle is rocked. The locking member must be removed from the insertion body by an operation, and there is a problem that the operation for adjusting the expansion/contraction is very troublesome.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an expansion and contraction device which can prevent the lock member from swinging out and which can be easily adjusted for expansion and contraction.

Specific means for solving the problems in the present invention are as follows.
The technical means of the present invention for solving this technical problem consists of a pair of left and right mantles 8 each having a substantially U-shaped cross section and having opening grooves 10 formed in the longitudinal direction on the opposing surfaces facing each other, A pair of left and right extensible bodies 5 which are inserted into the mantle 8 so as to be telescopic and have an insert body 9 whose lower end can be grounded, and both longitudinal ends of the left and right telescopic bodies 5 face the facing surfaces of the mantle 8. upper, middle, and lower tread members 6 that are connected in such a way as to form a structure, a lock mechanism 7 that fixes the inserts 9 inserted into the respective mantles 8 to the mantles 8 in the expanded and contracted positions; and an operation member 69 for locking and unlocking each locking mechanism 7,
The locking mechanism 7 includes a locked portion 11 provided along the longitudinal direction of the insert 9, a locking member 23 which is inserted into and removed from the outer cover 8 and engages and disengages from the locked portion 11, and the locking member 23, a biasing member 91 for biasing the lock member 23 in a locking direction, and a support frame 18 fixed to the jacket 8 and supporting the pivot shaft 24. An expansion device comprising:
The operation member 69 is arranged along the facing surface of the outer cover 8 from the vicinity of the lock mechanism 7 to the vicinity of the connecting position between the outer cover 8 and the upper tread member 6 while blocking the opening groove 10 and being vertically movable. , an operation portion 70 is provided at the upper end of the operation member 69 to which a force is applied to move the operation member 69 up and down,
A connecting body 82 capable of closing the opening groove 10 is connected to the lower end of the operating member 69, and the locking member 23 is engaged and disengaged between the connecting body 82 and the locking member 23 by moving the operating member 69 up and down. An interlocking tool 27 is provided,
The supporting frame 18 is connected to the ends of the lower tread members 6 and holds the interlocking member 27 so as to be vertically slidable along the facing surface of the jacket 8 .

Another technical means of the present invention is that the operation portion 70 has a finger hook piece 74 below the upper surface of the upper tread member 6 for hooking a finger and pulling the operation member 69 upward. It is in.
Another technical means of the present invention is that the operation member 69 has a vertically elongated plate-like operation wall portion 69a and a pair of front and rear side wall portions 69b projecting outward from both front and rear ends thereof. The operation portion 70 is formed separately from the operation member 69 and arranged along the outer surface of the operation wall portion 69a.

Further, according to another technical means of the present invention, a retaining member 15 is provided at the upper end of the insert body 9 to abut against the support frame 18 to restrict the retaining member 15 from detaching from the mantle 8. (1) is provided so as to be retractable from between the operating member 69 and the interlocking member 27 to open the opening groove 10 .

Another technical means of the present invention is that the ends of the middle tread member 6 are attached to brackets 14 attached to the front and rear walls 13F and 13R of the jacket 8 via fasteners 22,
The point is that an insertion space 21 is formed between the end portion of the middle tread member 6 and the facing surface of the jacket 8 so that the operation member 69 can be vertically movably inserted therethrough .

According to the present invention, a force can be applied to the operating portion 70 on the upper portion of the operating member 69 to perform the locking and unlocking operations of the lower locking mechanism.
Further, according to the present invention, finger force can be applied to the operating portion 70 below the upper surface of the upper step member 6 .
Further, according to the present invention, the operation portion 70 is attached along the outer surface of the operation wall portion 69a of the operation member 69. As shown in FIG.
Further, according to the present invention, the interlocking member 27 is attached to the operation wall portion 69a of the operation member 69 via the connecting body 82. As shown in FIG.
Further, according to the present invention, the operation member 69 can be formed to have an operation wall portion 69a and a pair of front and rear side wall portions 69b.
Further, according to the present invention, the insertion space 21 can be formed between the end portion of the middle tread member 6 and the facing surface of the jacket 8 so that the operation member 69 can be vertically movably inserted therethrough.

BRIEF DESCRIPTION OF THE DRAWINGS It is a partially cross-sectional front view of the stepladder which shows one Embodiment of this invention. It is a perspective view of the same support|pillar. It is the side view seen from the inside of the same support|pillar. It is front sectional drawing of the same support|pillar lower part. It is front sectional drawing of the lower part of a support|pillar in the state which released the same lock. It is front sectional drawing of the same support|pillar upper part. FIG. 5 is a cross-sectional view taken along line AA of FIG. 4; FIG. 7 is a cross-sectional view taken along line BB of FIG. 6; 3 is an exploded perspective view of a lock member, a handle, and the like; FIG. It is an exploded perspective view of a lower guide member, a connecting body, an interlocking tool, and the like. It is the whole stepladder side view.

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings.
1 to 11 show the configuration of a stepladder to which the expansion device of the present invention is applied. 1 and 11, a stepladder 1 is mainly constructed by pivotally supporting the upper portions of a pair of ladders 2 opposed to each other by means of pins 4 via brackets 3. As shown in FIG. This stepladder 1 can be used by leaning a pair of ladders 2 against a ground surface, and one of the ladders 2 can be lifted by unlocking an opening stopper that locks both the ladders 2 so as not to open the pair of ladders 2. It can be used by rotating it around the pin 4 .

The ladder 2 comprises a pair of telescoping struts 5 (extendable bodies) spaced apart in the left and right direction, a plurality of tread members 6 connecting the left and right stanchions 5, and the struts 5 and the tread members 6. It has a lock mechanism 7 provided between.
In the following description, for convenience of explanation, as shown in FIG. As indicated by 11, the parallel direction of the ladders 2 (horizontal direction on the paper surface of FIG. 11) is defined as the front-rear direction.

Each strut 5 has a strut body 8 (enclosure) formed of a channel material and a square tube-shaped pedestal 9 (insert) inserted into the strut body 8. The pillar 5 can be expanded and contracted by sliding the pillar 5 in the axial direction (up and down direction), and the pedestal 9 is fixed at a predetermined position where it has been expanded and contracted by the lock mechanism 7 so as not to move in the axial direction. there is
1 to 10, the column main body 8 is made of a metal such as aluminum and is formed in a substantially U-shaped cross section. is formed.

The pedestal 9 is made of a metal such as aluminum like the pillar main body 8, and has a plurality of locked portions 11 (rack portions) on the side walls of positions corresponding to the opening grooves 10 on the opposite side of the pillar main body 8. is formed. A grounding member 12 is attached to the lower end of the pedestal 9, and the ladder 2 is stably grounded on the ground surface by the grounding member 12. - 特許庁A locking member 15 is provided on the upper part of the pedestal 9, which is an insertion base, to protrude outward from the opening groove 10 to prevent the pedestal 9 from coming off from the pillar main body 8 by contacting a support frame 18 of the lock mechanism 7, which will be described later. It is

As shown in FIG. 6, the retainer member 15 is detachably fixed to the leg portion 9 with a fastener 17 such as a bolt.
The tread member 6 is formed in the shape of a rectangular tube, and the upper and lower surfaces of the tread member 6 are inclined so as to shift upward or downward from the front side to the rear side. Anti-slip unevenness is formed along its longitudinal direction.

The tread members 6 (6b) in the intermediate part of the ladder 2 are fixed between the left and right column bodies 8 via plate-like brackets 14 attached to the front and rear walls 13F, 13R of the column body 8. As shown in FIG.
The plate-shaped brackets 14 are arranged in front and rear pairs corresponding to the outer ends of the tread member 6, and each bracket 14 has a pillar fixing portion 14a and a tread fixing portion 14b via a stepped portion 14c. The column fixing portion 14a is fixed to the column body 8 with a fixing member 22 such as a rivet, and the tread fixing portion 14b is fixed to the outer end of the tread member 6 with a fixing member 22 such as a rivet, as shown in FIG. Thus, an insertion space 21 for an elongated operation member 69 to be described later is formed between the outer surface of the strut body 8 and the end of the tread member 6 .

The locking mechanisms 7 are provided between the lowermost tread members 6a of the ladder 2 and the struts 5, respectively. A lock mechanism 7 is attached to the .
The lock mechanism 7 comprises a support frame 18 fixed to the column main body 8 and pivotally supported on the support frame 18 so as to be swingable in the left-right direction (direction a in FIGS. 4 and 5). A lock member 23 that engages with the locking portion 11, a pivot shaft 24 that pivotally supports the lock member 23, and a handle that is supported by the pivot shaft 24 and pivots the lock member 23 away from the pedestal 9. 25 and .

As will be described later, the lock member 23 is freely swingable in the left-right direction about a pivot shaft 24 supported by the support frame 18. By swinging the lock member 23, the lock member 23 can be freely engaged with and disengaged from the pedestal 9. It can be done.
The lock mechanism 7 has an interlocking member 27 movably supported by the support frame 18 between the lock position X and the unlocking position Y shown in FIGS. 27, the locking member 23 is engaged with the pedestal 9 when the interlocking member 27 moves to the locked position X, and the locking member 23 is engaged with the pedestal 9 when the interlocking member 27 moves to the unlocked position Y. and an interlocking means 29 for separating from the lock member 23, preventing the locking member 23 from swinging out when the interlocking member 27 moves to the locking position X, and swinging the locking member 23 out when the interlocking member 27 is disengaged from the locking position X. is provided.

The support frame 18 is formed into a box shape by bending a sheet of metal such as aluminum, and is attachable to the support body 8 and the tread member 6. A pair of front and rear side wall portions 32F and 32R attached to the front and rear walls 13F and 13R of the support body 8 and extending toward the opposing portions, and a locked portion of the pedestal 9. 11 and disposed between the front and rear side wall portions 32F and 32R, and a pair of tread bars projecting downward from the lower portions of the front and rear side wall portions 32F and 32R and attached to the tread member 6. It has mounting portions 34F and 34R.

The outer side portions of the front and rear side wall portions 32F and 32R of the support frame 18 are formed so as to be able to sandwich the front and rear walls 13F and 13R of the column body 8. , 13R, and a fixing member 22, such as a rivet, is driven into them to attach the support frame 18 to the column body 8. As shown in FIG.
The tread mounting portions 34F and 34R of the support frame 18 are formed so as to be able to sandwich the end portions of the front and rear walls 26F and 26R of the tread member 6. The support frame 18 is attached to the tread member 6 by sandwiching the ends of the walls 26F and 26R and driving fixtures 22 such as rivets thereon.

Therefore, the support frame 18 has the function of a bracket for connecting the tread member 6 to the strut 5, so that the number of brackets for mounting the tread member 6 to the strut 5 can be reduced. can.
When the support frame 18 is attached to the tread member 6 , the inclined portion 16 on the upper surface side of the tread member 6 protrudes into the support frame 18 . The back wall portion 33 of the support frame 18 is formed in the shape of a vertical plate extending in the front-rear direction.

The pivot shaft 24 is formed in a cylindrical shape, is provided through the front and rear side walls 32F and 32R of the support frame 18, and is rotatably supported in the same direction as the rocking direction of the lock member 23. As shown in FIG.
A retainer ring 37 having a larger diameter than the pivot shaft through hole 36R (one of the pivot shaft through holes 36F, 36R) of the rear wall portion 32R is attached to the tip of the pivot shaft 24. When the support shaft 24 is pulled forward, the retainer ring 37 comes into contact with the rear side wall portion 32R and acts as a stopper to prevent the pivot shaft 24 from slipping out of the pivot portion through hole 36R.

As shown in FIGS. 3, 4, 5, and 9, the handle 25 includes a grip portion 41 and an operating portion 42 projecting from the grip portion 41 toward the interlocking member 27. The grip portion 41 is a pivot shaft. It is fixed to one end (front end) of 24 by welding or the like, is arranged along the outer surface of front wall portion 32F, and connects front side of pivot shaft 24 and operating portion 42 . The operating portion 42 is formed in a cylindrical shape and protrudes rearward at a position radially separated from the pivot shaft 24 . The pivot shaft 24, the grip portion 41, and the operating portion 42 form a substantially U-shape when viewed from the side.

The operating portion 42 of the handle 25 is inserted through an operating portion through-hole 44 provided in the lower portion of the front wall portion 32</b>F of the support frame 18 . The operating portion through-hole 44 is formed in an arc shape centered on the axis of the pivot shaft 24 (the center of the pivot shaft through-holes 36F and 36R).
A grip portion 41 of the handle 25 integrally connects the pivot shaft 24 and the operating portion 42 . A handle cover 47 made of synthetic resin is fitted over the gripping portion 41, the front portion of the pivot shaft 24, and the front portion of the operating portion 42. The handle cover 47 covers the grip portion 41, the front portion of the pivot shaft 24, and the operating portion. It covers the front and perimeter of 42. At the bottom of the handle cover 47, a left and right knob 48 is projected downward.

The lock member 23 is arranged between the front and rear wall portions 32F and 32R of the support frame 18, and is arranged outside the operating portion 42 and the pivot shaft mounting portion 49 mounted approximately in the center of the front and rear of the pivot shaft 24. and a locking portion 52 that engages with the locked portion 11 of the pedestal 9 .
The pivot shaft attachment portion 49 of the lock member 23 is rotatably fitted onto the pivot shaft 24, and the lock member 23 is supported to swing about the pivot shaft 24 in the lateral direction (direction a). ing. A pressing portion 54 projects from the lower portion (free end side) of the lock member 23 toward the interlocking member 27 , and an operation piece 55 projects inward from the pivot shaft mounting portion 49 .

As shown in FIGS. 4, 5, and 10, the interlocking member 27 includes a pair of front and rear side walls 27a, an upper wall 27b connecting the upper portions of the front and rear side walls 27a, and a spine connecting inner ends of the front and rear side walls 27a in the left-right direction. The lock member 23 is formed in a box shape with an open outer side having a wall 27c and is disposed inwardly in the left-right direction of the lock member 23 in the support frame 18 so as to protrude upward. It is held so as to be vertically slidable (movable) along. Accordingly, the interlocking members 27 of the left and right support frames 18 are held so as to be movable in the longitudinal direction along the facing surfaces of the left and right column main bodies 8, respectively.

A square tubular body 57 is projected outward from the upper part of the back wall 27c of the interlocking member 27. The upper part of the square tubular body 57 is a first pushing piece 58, and the lower part is a second pushing piece 59. The first pushing piece 58 and the second pushing piece 59 are separated vertically while sandwiching the tip of the operating piece 55 . A restricting portion 60 projects outward from the lower portion of the rectangular tubular body 57 of the back wall 27c, and a pair of front and rear cam walls 61 having arcuate cam surfaces 61a are provided on both front and rear sides of the restricting portion 60. As shown in FIG.

A pair of front and rear connecting pieces 62 project upward from the upper wall 27b of the interlocking member 27, and mounting holes 63 are provided in each of the connecting pieces 62. As shown in FIG.
The interlocking means 29 includes an operating piece 55 projecting from the lock member 23, and a first pushing piece 58 and a second pushing piece 59 projecting from the interlocking member 27. The piece 58 and the second pushing piece 59 sandwich the operation piece 55 in the moving direction of the interlocking member 27, and swing the locking member 23 in the engaging direction when the interlocking member 27 moves to the locking position X. The first pushing piece 58 pushes the operating piece 55 to move the operating piece 55, and the second pushing piece 59 pushes the operating piece 55 to swing the locking member 23 in the disengaging direction when the interlocking member 27 moves to the unlocking position Y. is configured to push the

In the case of this embodiment, when the interlocking member 27 moves from the unlocked position Y to the locked position X, first, the restricting portion 60 pushes the pressing portion 54 downward to move the locking member 23 in the engagement direction. After that, the first push piece 58 pushes the operation piece 55 downward, and when the interlocking member 27 moves to the lock position X, the lock member 23 is swung in the engagement direction. movement is completed.

The detachment preventing means 30 includes a pressing portion 54 protruding toward the interlocking member 27 on the rocking end side of the lock member 23 and a restricting portion 60 protruding from the interlocking member 27 toward the pressing portion 54 . When the interlocking member 27 moves to the locking position X, the pressing part 54 and the restricting part 60 face each other to prevent the lock member 23 from swinging out, and the interlocking member 27 is disengaged from the locking position X. When the restricting portion 60 is disengaged from the position facing the pressing portion 54, the locking member 23 is configured to be allowed to swing apart.

4 so that when the interlocking member 27 moves from the lock position X to the unlock position Y, the lock member 23 starts swinging apart after the restricting portion 60 is disengaged from the pressing portion 54. As shown, an idle gap 65 is formed between the second pushing piece 59 and the operating piece 55 .
By rotating the handle 25 about the pivot shaft 24 left and right inward in the direction of arrow a, the interlocking member 27 is pushed to the unlocking position Y against the bias of the biasing member 91, which will be described later. A tool pushing means 67 is provided between the grip part 41 and the interlocking tool 27 . The interlocking device pushing means 67 is composed of the outer peripheral surface of the operating portion 42 and the cam surfaces 61 a of the front and rear cam walls 61 of the interlocking device 27 .

As shown in FIGS. 2, 3, 6, 8 and 10, an elongated operation member 69 for operating the lock member 23 is arranged on the outer surface of the post body 8 so as to block the opening groove 10. . The elongated operation member 69 is held along the outer surface of the column main body 8 so as to be movable in the longitudinal direction, and is inserted and held in the insertion space 21 so as to be vertically movable. The interlocking tool 27 is connected to the lower end (one end) of the long operation member 69 via a connecting body 82 described later, and the operation part 70 is provided to the upper end (the other end) of the long operation member 69 . .

The long operation member 69 has a plate-like operation wall portion 69a that is elongated in the vertical direction, and a pair of front and rear side wall portions 69b projecting outward from both front and rear end portions of the operation wall portion 69a. An upper locking hole 71 and a lower locking hole 72 are provided in the lower portion with a vertical interval therebetween, and these locking holes 71 and 72 are formed in a rectangular shape elongated in the front-rear direction.
The operating portion 70 is formed separately from the long operating member 69, and includes a mounting wall 70a arranged along the outer surface of the long operating member 69, and an upper portion of the mounting wall 70a bent outward. The mounting wall 70a is fixed to the long operation member 69 with a fixture 22 such as a rivet, and the top wall 70b extends upward from the outer end of the top wall 70b. A hook-shaped finger hook piece 74 protrudes toward the end.

The column body 8 is provided with an upper guide member 76 and a lower guide member 77 for movably guiding the long operation member 69 .
As shown in FIGS. 2, 3, and 6, the upper guide member 76 includes a pair of front and rear side walls 76a, a vertical plate-like back wall 76b connected to the upper left and right inner ends of the front and rear side walls 76a, and a back wall 76b. A slanted wall 76c sloping outwardly downward from the lower portion of the wall 76b and connected to the front and rear side walls 76a, and a vertical plate-like support wall 76d standing upward from the lower portion of the slanted wall 76c and connected to the front and rear side walls 76a. The front and rear side walls 76a are fixed to the front and rear side walls 13F and 13R of the column body 8 by driving fixing tools 22 such as rivets, and the long operating member 69 is provided between the support wall 76d and the outer surface of the column body 8. The upper part is held vertically movably. A drain hole for draining rainwater is provided in the lower portion of the inclined wall 76c.

As shown in FIGS. 2, 3, and 10, the lower guide member 77 includes a pair of front and rear side walls 77a, a rear wall 77b connecting the inner ends of the front and rear side walls 77a, and a rear wall 77b protruding inward from the rear wall 77b. It has a pair of front and rear storage side walls 77c and an upper spring receiving wall 79 protruding inward from the upper portion of the back wall 77b so as to block the space between the upper portions of the storage side walls 77c.
A stepped portion 80 is provided in the middle portion in the left-right direction of the front and rear side walls 77a, and an engaging piece 81 protrudes inward in the front and rear direction from the step portion 80, and the outer portions of the front and rear side walls 77a are rivets. It is fixed to the front and rear side walls 13F and 13R of the column main body 8 by hammering fixtures 22 such as the like, and between the stepped portion 80 and the engaging piece 81, the front and rear ends of the long operation member 69 are vertically movable. sandwiched.

As shown in FIGS. 2 , 3 , 4 , 5 and 10 , a connecting body 82 is provided between the interlocking member 27 and one end of the long operating member 69 . The connector 82 has a front wall 82a and a rear wall 82b on the left and right sides. The rear wall 82b projects upward from the front wall 82a. , and an upper engagement piece 83 that is bent upward and outward in a stepped manner protrudes from the outer portion of the upper wall 82c. A bottom wall 82d is provided to connect the lower part of the back wall 82b and the lower part of the front wall 82a. A lower spring receiving wall 86 is provided to connect the middle portion of the wall 82b, and a connecting wall 82e is provided to connect the front wall 82a, the back wall 82b, the bottom wall 82d, and the lower spring receiving wall 86 to the front and rear central portions thereof, A hook-shaped lower engaging piece 84 protrudes outward from the upper portion of the front wall 82a.

The upper engaging piece 83 is detachably engaged with the upper locking hole 71 of the long operating member 69, and the lower engaging piece 84 is detachably engaged with the lower locking hole 72, whereby the connection is achieved. The body 82 is detachably connected and fixed to the lower portion of the long operating member 69 so as to protrude downward.
The connecting body 82 is placed on the upper wall 27b of the interlocking member 27 via the bottom wall 82d, and the connecting member 82 is connected by inserting a fastener 88 such as a bolt nut into the front and rear connecting pieces 62 and the connecting tube 85 and tightening them. The body 82 is detachably connected to the interlocking tool 27 .

A spring storage case 89 is formed by the upper half of the back wall 82b of the connecting member 82, the lower spring receiving wall 86, the front and rear storage side walls 77c of the lower guide member 77, and the upper spring receiving wall 79. As shown in FIG.
The coil spring 90 is vertically accommodated in the spring storage case 89 , the upper end of the coil spring 90 is received by the upper spring receiving wall 79 , the lower end of the coil spring 90 is received by the lower spring receiving wall 86 , and the lower guide member 77 is supported by the coil spring 90 . The connector 82 to the interlocking member 27 are urged downward. Therefore, the interlocking member 27 is urged to the locking position X by the urging member 91 composed of the coil spring 90 .

Further, the upper engaging piece 83 and the lower engaging piece 84 are removed from the upper engaging hole 71 or the lower engaging hole 72 to remove the connecting body 82 from the long operation member 69, and the fastener 88 is removed to remove the connecting body 82. from the interlocking member 27 , the connecting member 82 can be retracted from between the long operation member 69 and the interlocking member 27 to open the opening groove 10 .
Alternatively, by removing the connecting body 82 from the long operating member 69, loosening the tightening tool 88, and rotating the connecting body 82 inwardly around the tightening tool 88, the connecting body 82 can be attached to the long operating member. The opening groove 10 can be opened by retracting from between the 69 and the interlocking member 27.例文帳に追加

As a result, a tool can be inserted through the opening groove 10 to remove the retaining member 15 attached to the top of the pedestal 9, thereby removing the damaged pedestal 9 from the pillar body 8 and replacing or repairing it. You can
According to the above-described embodiment, as shown in FIG. 4, the lock member 23 is engaged with the locked portion 11 of the pedestal 9, and the pedestal 9 is immovably locked with respect to the pillar main body 8. When adjusting the expansion/contraction of the post 5, if a finger is hooked on the finger hook piece 74 of the operating portion 70 and the long operating member 69 is pulled upward, the interlocking member 27 resists the biasing force of the biasing member 91 and is locked at the locked position X. to the unlocked position Y. Alternatively, when the knob 48 of the handle cover 47 is grasped and the handle 25 is swung left and right inward in the direction of the arrow a around the pivot shaft 24, the operating portion 42 pushes the cam surface 61a upward and the interlocking member 27 is attached. It moves from the locked position X to the unlocked position Y against the biasing force of the force member 91 .

When the interlocking member 27 moves from the locking position X to the unlocking position Y, the idle gap 65 exists between the second pushing piece 59 and the operation piece 55. Therefore, when the interlocking member 27 moves upward, The restricting portion 60 is disengaged from the position facing the pressing portion 54, and the detachment prevention means 30 is released to prevent the locking member 23 from being detached. After that, the second pushing piece 59 pushes the operating piece 55 upward, and the locking member 23 starts to swing apart, and the locking member 23 swings in the separating direction. When the interlocking member 27 moves to the unlocked position Y, the detachment of the pedestal 9 of the locking member 23 from the engaged portion 11 is completed. As a result, the pedestal 9 becomes movable with respect to the pillar body 8, and the pillar 5 can be expanded and contracted.

In order to lock the pedestal 9 immovably with respect to the pillar body 8 after the pillar 5 has been extended and contracted, the upward pulling of the long operation member 69 is released, or the swinging operation of the handle 25 is released. Then, the long operation member 69 to the interlocking member 27 are moved downward by the urging force of the urging member 91, and the interlocking member 27 is moved from the unlocked position Y to the locked position X. As shown in FIG.
When the interlocking member 27 moves from the unlocked position Y to the locked position X, first, the regulating portion 60 pushes the pressing portion 54 downward to swing the locking member 23 in the engagement direction. After that, the first pushing piece 58 pushes the operating piece 55 downward, and when the interlocking member 27 moves to the locking position X, the rocking movement of the locking member 23 in the engaging direction is completed.

Further, when the interlocking member 27 moves to the locking position X, the pressing portion 54 and the restricting portion 60 face each other, and the detachment prevention means 30 prevents the lock member 23 from swinging in the detachment direction. As a result, the locking member 23 engages with the locked portion 11 of the pedestal 9 , thereby locking the pedestal 9 to the pillar body 8 so that it cannot move. Moreover, the detachment prevention means 30 prevents the locking member 23 from swinging in the detachment direction, and the pedestal 9 can be reliably prevented from unexpectedly expanding and contracting with respect to the column body 8 .

Therefore, when the interlocking member 27 moves to the locking position X, the interlocking means 29 engages the locking member 23 with the pedestal 9, and at the same time, the engagement of the locking member 23 with the pedestal 9 is prevented by the detachment prevention means 30. It is possible to prevent accidental detachment. Moreover, when the interlocking member 27 is disengaged from the locking position X, the detachment preventing means 30 allows the locking member 23 to swing out, and the movement of the interlocking member 27 from the locking position X to the unlocking position Y causes the locking member 23 to move. Engagement with and disengagement from the pedestal 9 can be easily changed, and expansion and contraction adjustment can be easily performed.

In addition, since the long operation member 69 is arranged along the outer surface of the post body 8, the lock mechanism 7 and the long operation member 69 do not interfere with the use of the stepladder 1. Moreover, since the locking mechanism 7 and the long operation member 69 are arranged outside the pedestal 9, the pedestal 9 can be formed of a cylindrical body, which is advantageous in terms of strength. Further, by using the long operating member 70 , it is possible to easily operate the locking member 23 to be engaged with and disengaged from the pedestal 9 from a location away from the locking mechanism 7 .

The invention according to this embodiment is not limited to the above embodiment. In the above embodiment, the telescopic device is applied to the stepladder 1 having the telescopic support 5, but instead of this, the telescopic device may be applied to the ladder 2, scaffolding, and the like.
Further, the expandable body is not limited to the support 5 composed of the support main body 8 and the pedestal 9, and the expandable body may be any member as long as the pedestal 9 is inserted into a tubular member and the whole expands and contracts.

Further, in the above-described embodiment, when the interlocking member 27 moves from the unlocking position Y to the locking position X, first, the restricting portion 60 pushes the pressing portion 54 downward to swing the locking member 23 in the engaging direction. After that, the first pushing piece 58 pushes the operating piece 55 downward. The lock member 23 may be swung in the engagement direction only when the first push piece 58 pushes the operation piece 55 downward.

1 stepladder (extension device)
2 Ladder 5 Post (extendable body)
6 tread member 7 locking mechanism 8 strut body (outer body)
9 pedestal (insert)
REFERENCE SIGNS LIST 10 opening groove 11 engaged portion 13 retention member 18 support frame 21 insertion space 23 lock member 24 pivot shaft 25 handle 27 interlocking tool 29 interlocking means 30 detachment prevention means 41 gripping portion 42 operating portion 54 pressing portion 55 operating piece 58 First pushing piece 59 Second pushing piece 60 Regulating portion 65 Idle gap 67 Interlocking device pushing means 69 Long operating member 70 Operating portion 77 Lower guide member 82 Connecting body 90 Coil spring 91 Biasing member

Claims (5)

A pair of left and right mantle bodies (8) which are generally U-shaped in cross section and have opening grooves (10) formed in the longitudinal direction on the opposing surfaces facing each other, and a telescopic body within the mantle bodies (8). A pair of left and right stretchable bodies (5) having an insert (9) which is inserted and whose lower end can be grounded, and both longitudinal ends of the left and right stretchable bodies (5) are opposed to the facing surfaces of the outer cover (8). The upper, middle, and lower tread members (6) connected to each other and the inserts (9) inserted into each mantle (8) are stretched and stretched against the mantle (8). It comprises a locking mechanism (7) for fixing and an operation member (69) for locking and unlocking each locking mechanism (7),
The lock mechanism (7) includes a locked portion (11) provided along the longitudinal direction of the insert (9), and a locked portion (11) that is inserted into and removed from the mantle (8). A lock member (23) to be released, a pivot shaft (24) for swingably supporting the lock member (23), and an urging member (91) for urging the lock member (23) in the direction of locking operation. and a support frame (18) fixed to the mantle (8) and supporting a pivot shaft (24), comprising:
The operation member (69) extends from the vicinity of the lock mechanism (7) to the vicinity of the connecting position between the outer body (8) and the upper tread member (6) along the facing surface of the outer body (8). The operation member (69) is provided with an operation part (70) to which a force for moving the operation member (69) up and down is applied to the upper end of the operation member (69),
A connecting body (82) capable of closing the opening groove (10) is connected to the lower end of the operating member (69), and the operating member (69) is placed between the connecting body (82) and the lock member (23). is provided with an interlocking tool (27) that engages and disengages the lock member (23) by vertical movement of the
The support frame (18) is connected to the end portion of the lower tread member (6) and holds the interlocking member (27) so as to be slidable up and down along the facing surface of the mantle (8). A telescopic device characterized by: The operation part (70) is characterized by having a finger hook piece (74) which is located below the upper surface of the upper step member (6) and hooks a finger to pull the operation member (69) upward . The expansion device according to claim 1. The operation member (69) has a plate-shaped operation wall (69a) elongated in the vertical direction and a pair of front and rear side walls (69b) protruding outward from both front and rear ends thereof. 3. The expansion device according to claim 1, wherein (70) is formed separately from the operating member (69) and arranged along the outer surface of the operating wall portion (69a). A retainer member (15) is provided at the upper end of the insert (9) to abut against the support frame (18) to prevent it from coming off from the mantle (8), and the connector (82) is open. The extension device according to any one of claims 1 to 3, characterized in that it is provided so as to be retractable from between the operating member (69) and the interlocking member (27) so as to open the groove (10). . The ends of the middle tread member (6) are attached to brackets (14) attached to the front and rear walls (13F, 13R) of the jacket (8) via fasteners (22),
An insertion space (21) is formed between the end of the middle tread member (6) and the facing surface of the outer body (8), into which the operating member (69) is vertically movably inserted. The expansion device according to any one of claims 1 to 4.

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