JP4937226B2 - Opening device for stepladder - Google Patents

Description

  The present invention relates to a stepladder prevention device in which the tops of a pair of ladder-like legs are pivotally attached to each other. The stepladder includes a dual-purpose stepladder that is also used as a ladder in a state where both legs are deployed horizontally, and a dedicated stepladder that is not used as a ladder because the ladder-like leg is long. In particular, the present invention relates to a dedicated stepladder stop device.

  Although a publicly known document such as a patent publication cannot be specifically cited as a conventional opening prevention device, a conventional opening prevention device for a dedicated stepladder is formed by pivotally attaching the tops of a pair of long ladder-like legs. A pair of opening guards is placed in an X-shape on both legs of the stepladder, the base ends of the two opening guards are pivotally attached to the upper sides of the legs, and the distal ends of the double opening guards are connected via lock fittings. And are removably fixed to the lower side of each leg.

  In the above conventional locking device, the structure of the locking bracket is complicated, and there is a problem that it takes time and effort to lock and unlock the tip of the locking rod with respect to the lower side required portion of the ladder-like leg. It was.

  In view of the above circumstances, an object of the present invention is to provide an opening preventing device capable of locking and unlocking the front end portion of an opening stop rod with respect to a lower side required portion of a ladder-like leg body by a simple operation.

Means for solving the above problems will be described with reference numerals in the embodiments described later. The invention according to claim 1 is formed by pivotally connecting the top portions of the pair of ladder-like legs 2 and 2. A pair of opening guards 4, 4 are stretched in an X shape on both legs 2, 2 of the stepladder 1, and the base ends of the two opening stoppers 4, 4 are pivotally attached to the upper sides of the legs 2, 2, respectively. A stepladder stop device for fixing the front ends of the legs 2 and 2 to the lower sides of the legs 2 and 2 respectively;
A pin insertion hole 11 is provided on the side of the front end portion of each locking bar 4, and a pin with a locking head 12 is inserted through the pin insertion hole 11 of the locking bar 4 along the head 12 on the lower side of each leg 2. 13, and the lock fitting 7 is opened and closed on the front end side of the opening stopper rod 4 so as to open and close to a closing posture that overlaps the opening stopper rod 4 in parallel and an opening posture in which the lower end side rises from the opening stopper rod 4. on the upper end side pivotally attached, Ri Na provided engaging Hamamizo 14 for locking and Kakarihama from above with respect to the pin 13 when going closed from the attitude open the lock fitting 7 to the lock fitting 7,
Further, the opening stopper 4 is formed of a square tube, and an end cap 15 made of synthetic resin is fitted and fixed to the distal end portion thereof, and outward projections 18 projecting from both side portions of the end cap 15 are provided. 18 is protruded from the openings 16 on both side portions of the front end of the opening stop rod 4, and the lock fitting 7 is formed in a U-shape that can be fitted to and removed from the opening stop rod 4 by the left and right side wall portions 7a, 7a and the upper wall portion 7b. The left and right side wall portions 7a and 7a are respectively provided with inwardly protruding portions 21 and 21 on the distal end side of the inner surface such that the opposing distance Wa is smaller than the outer distance Wb of the outwardly protruding portions 18 and 18. When the lock fitting 7 is closed from the open position, the inward projections 21 and 21 of the left and right side wall portions 7a and 7a are locked by exceeding the outward projections 18 and 18 of the end cap 15. And

  According to a second aspect of the present invention, in the step stopper device for the stepladder according to the first aspect, the hole diameter of the pin insertion hole 11 is d1, the outer diameter of the locking head 12 is d2, and the groove width of the engaging groove 14 is If d3 and the outer diameter of the pin 13 is d4, d1> d2> d3> d4.

  A third aspect of the present invention relates to the step opening preventing device for the stepladder according to the first or second aspect, wherein the other side surface with respect to the pin insertion hole 11 provided on one side surface portion of the front end portion of each of the opening stopper rods 4. A through hole 11a is provided at a position facing the pin insertion hole 11 in the part.

According to a fourth aspect of the present invention, in the step stopper device for the stepladder according to the first aspect , the lock fitting 7 has an opening / closing operation piece 23 extending from the tip of the upper wall portion 7b.

The effect of the invention by the above means will be described with reference numerals of embodiments to be described later. According to the opening preventing device of the invention according to claim 1, the lock fitting attached to the front end side of the opening stopper 4. 7 with the locking head 12 projecting on the leg body 2 side in a state where 7 is in an open posture, together with the locking head 12, the pin 13 is inserted into the pin insertion hole 11 at the tip of the opening stopper 4. By closing the lock fitting 7, the engagement groove 14 on the lock fitting 7 side is engaged with the pin 13, so that the locking stopper 4 is locked. Since the pin insertion hole 11 at the distal end portion of the opening stopper rod 4 may be removed from the pin 13 with the pin 12, the opening stopper rod 4 can be easily locked and unlocked.
According to the opening prevention device of the first aspect of the present invention, when the lock fitting 7 is closed from the open position in the locking operation, the engagement groove 14 of the lock fitting 7 is engaged with the pin 13 and If the projecting portions 21 and 21 projecting in the opposite direction exceed the outward projecting portions 18 and 18 made of synthetic resin projecting outward from the openings 16 on both side surfaces of the opening stopper rod 4, the lock fitting 7 is Unless it is forcibly returned to the open position, the lock is not released, so that the locked state can be reliably maintained. Further, when closing the lock fitting 7, there is a “click” feeling when the inward projection 21 on the lock fitting 7 side gets over the outward projection 18 on the stopper 4 side. It can be confirmed that the metal fitting 7 is securely locked in the closed position.

  As described in claim 2, the hole diameter of the pin insertion hole 11 is d1, the outer diameter of the locking head 12 is d2, the groove width of the engagement groove 14 is d3, and the outer diameter of the pin 13 By setting d1> d2> d3> d4 where d4 is d4, it is possible to quickly and easily perform the locking and unlocking operation of the opening stopper rod 4 accurately.

  The position which opposes the said pin insertion hole 11 in the other side surface part with respect to the said pin insertion hole 11 provided in one side surface part of the front-end | tip part of each said opening stop rod 4 as described in Claim 3. By providing the through-hole 11a in the hole, the through-hole 11a can be used as a monitoring hole for confirming whether or not the pin 13 with the locking head 12 is securely inserted into the pin insertion hole 11 of the one side surface portion. There is.

According to the fourth aspect of the present invention, since the opening / closing operation piece 23 is extended from the tip of the upper wall portion 7b to the lock fitting 7, this opening / closing operation is performed when the lock fitting 7 is locked and unlocked. By grasping the piece 23, the operation can be performed quickly and easily.

  A preferred embodiment of the present invention will be described below with reference to the drawings. FIG. 1 (a) is a front view of a stepladder according to the present invention, (b) is a side view, and FIG. ) Is an enlarged view of the portion indicated by arrow A in FIG. 1A, FIG. 3B is a cross-sectional view of the portion indicated in FIG. 1A, and FIG. 3A is an arrow in FIG. (B) is a cross-sectional view of the portion shown in (a), (c) is a cross-sectional view taken along the line CC of (a), and (d) is a lock in a locked closed position. (E) is a sectional view taken along the line DD of (d), and (a) and (b) of FIG. 4 are explanatory views showing a method of fixing the front end of the opening stopper rod. 5 (a) and 5 (b) are explanatory views showing the fixing method.

  A stepladder 1 shown in FIG. 1 is formed by pivoting the tops of a pair of ladder-like legs 2 and 2 with a pivot fitting 3, and each leg 2 is formed as shown in FIG. In this case, the crosspiece 6 is formed in a multi-stage manner between the side frames 5 and 5 that are arranged so as to spread downward. Thus, both legs 2 and 2 are fixed at a constant opening angle as shown in FIG. In other words, a pair of opening stoppers 4 and 4 are spanned in an X shape on both legs 2 and 2, and the base ends of the opening stoppers 4 and 4 are pivotally attached to the upper sides of the legs 2 and 2, respectively. In addition, the respective front ends of the double-opening stoppers 4 and 4 are fixed to the lower sides of the both legs 2 and 2 by the opening-stopping device.

  As shown in FIGS. 2 to 5, the opening stoppers 4 are each formed of a square tube, and the base end portion (upper end portion) of the opening stoppers 4 has the legs 2. A pivot 10 is pivotally attached to an upper bracket 8 attached to the upper side of the side frame 5 to be formed, and a pin insertion hole 11 (see FIG. 6) is provided on the side surface of the distal end (lower end) of the opening stopper rod 4. An opening stopper bracket 9 is attached to a required position on the lower side of the side frame 5, and the stopper bracket 9 is provided at the tip of the stopper bar 4 as shown in FIG. A pin 13 with a locking head 12 that is inserted through the pin insertion hole 11 together with the locking head protrudes.

  Further, on the front end side of the opening stopper 杆 4, the lock fitting 7 overlaps in parallel with the opening stopper 杆 4 (see FIG. 5 (b)) and the lower end rises from the opening stopper 杆 4 (see FIG. 5). 4 (see (a) and (b) of FIG. 4), the upper end side is pivotally attached by a pivot 24 so as to open and close, and when the lock fitting 7 is closed from the open position, the pin with the locking head 12 is attached. An engaging groove 14 is provided for engaging and locking the 13 pins 13 themselves from above. The engaging groove 14 is formed to have a groove width slightly larger than the outer diameter of the pin 13, and cannot be detached from the locking head 12 when engaged with the pin 13. That is, as shown in FIGS. 3 (d) and 3 (e), the diameter of the pin insertion hole 11 provided at the distal end portion of the opening stopper rod 4 is d1, and the pin protruding from the receiving metal fitting 9 is provided. If the outer diameter of the locking head 12 attached to 13 is d2, the groove width of the engaging groove 14 provided in the lock fitting 7 is d3, and the outer diameter of the pin 13 is d4, d1> d2 > D3> d4, and by doing so, it is possible to quickly and easily perform the locking and unlocking operation of the opening stopper rod 4 accurately. Further, an end cap 15 made of synthetic resin is fitted and fixed in the front end portion of the opening stopper rod 4.

  6A shows a state in which the end cap 15 is about to be inserted into the front end portion of the opening stopper rod 4 made of a square tube, and FIG. Indicates the front end of the locking bar 4 with the end cap 15 inserted and fixed. As shown in FIG. 6 (a), the opening guard 4 is a rectangular tube made up of an upper wall 4a, a lower wall 4b, and left and right side walls 4c, 4c, and a notch opening 16 is formed at the tip of the left and right side walls 4c, 4c. , 16 are provided, a pin insertion hole 11 is provided at a predetermined position near the notch opening 16, and a screw insertion hole 17 is provided at the tip of each of the upper wall 4a and the lower wall 4b.

  7A is a perspective view showing the end cap 15, FIG. 7B is a front view, FIG. 7C is a plan view, FIG. 7D is a side view, and FIG. 7E is a bottom view. The end cap 15 is formed integrally with a synthetic resin, and has a hollow rectangular cap body 15 a that fits into the front end of the locking stopper 4, and has a diameter larger than that, and the tip of the locking stopper 4. The cap body 15a is formed on a side surface of the cap body 15a corresponding to the left and right side walls 4c, 4c of the opening stopper rod 4 and is provided on the side surface of the opening stopper rod 4 with an outer surface protruding from the notch openings 16, 16. Directional protrusions 18 and 18 are formed. Both protrusions 18 and 18 are formed in a tapered shape as shown in FIG. That is, each protrusion 18 has a gentle upward slope 18a, a peak 18b in parallel, and a rear end 18c. Further, the cap body 15a is provided with a screw hole 19 at a position corresponding to the bolt insertion hole 17 on the side of the locking bar 4.

  Then, in order to insert and fix the end cap 15 into the front end portion of the opening stopper rod 4 made of a square tube, the end cap 15 is inserted into the front end portion of the opening stopper rod 4 from the state shown in FIG. Inserting the screws 20 into the screw holes 19 of the end cap 15 from the bolt insertion holes 17 in the state where both the protrusions 18 and 18 are protruded from the notch openings 16 and 16 of the opening stopper 4 respectively. A state as shown in FIG. 6B is obtained by screwing and tightening.

  8A is a perspective view of the lock fitting 7, FIG. 8B is a sectional view taken along line XX of FIG. 9A, and FIG. FIG. 5B is a front view showing a state in which the lock fitting 7 is in a closed position. FIG. The lock fitting 7 is formed by pressing a steel plate. The lock fitting 7 is formed in a U-shape that can be fitted to and detached from the opening stopper 4 by the left and right side wall portions 7a and 7a and the upper wall portion 7b. The inwardly projecting portions 21 and 21 are projected on the front end side of the inner side surfaces of the portions 7a and 7a so that the facing interval Wa is narrower than the outer distance Wb of the outwardly projecting portions 18 and 18 on the side of the opening stopper 4. (See (b) in FIG. 8 and (a) in FIG. 9). However, when the lock fitting 7 is closed from the open position while being fitted to the front end of the locking bar 4, the left and right side walls are directed inward. The protrusions 21 and 21 are locked when they cross the outward protrusions 18 and 18 of the end cap 15.

  In addition, the lock fitting 7 is provided with engagement grooves 14 and 14 for engaging and locking the pin 13 from above on the center side in the longitudinal direction of the side walls 7a and 7a. The proximal end side is extended slightly longer to form pivotal arm portions 7ao and 7ao, and an opening / closing operation piece 23 is extended from the distal end side of the upper wall portion 7b.

  In order to pivotally attach the lock fitting 7 to the opening guard 4, bolts provided on the pivoting arm portions 7ao and 7ao in a state where the lock fitting 7 is fitted to the front end side of the opening guard 4 from above. By inserting a rivet or bolt as the pivot 24 through the insertion holes 22 and 22 and the bolt insertion holes 25 and 25 provided in the opening stopper rod 4, the lock fitting 7 is fitted to the opening stopper rod 4 in parallel. Can be pivoted so as to open and close to a closed posture that overlaps with and an open posture in which the lower end side rises from the opening stopper rod 4.

Further, on the distal end side of the upper wall portion 7b of the lock fitting 7, the head of the end cap fixing screw 20 protruding from the distal end portion of the upper wall 4a of the locking bar 4 when the lock fitting 7 is in the closed posture. Since the hole 26 is formed so as to be received, the lock fitting 7 can be accurately fitted to the distal end portion of the opening stopper rod 4 in the closed position, as shown in FIG. 4 (b).

  The operation of the locking device constructed as described above will be described with reference to FIGS. 4 (a) and 4 (b) and FIGS. 5 (a) and 5 (b) with reference to other drawings.

  First, as shown in FIG. 4 (a), the lock fitting 7 is set in an open posture, and in this open posture, as shown in FIG. A pin 13 with a certain locking head 12 is inserted through the pin insertion hole 11 at the tip of the opening stop rod 4 together with the locking head 12, and as shown in FIG. When it is closed so as to be fitted to the front end portion of the locking stopper 4, the engagement groove 14 formed in the side wall portion 7a of the lock fitting 7 is engaged with the pin 13 ((a), (FIG. 3). b), (d), and (e)), as shown in FIG. 9 (a), protrusions 21 and 21 projecting inwardly toward the front end sides of the inner side surfaces of the side walls 7a and 7a are provided. As shown in (b) of the figure, by passing over the outward projections 18, 18 made of synthetic resin projecting outward from the openings 16 on both sides of the front end of the opening stopper rod 4, Click fitting 7 is locked in the closed position, in FIG. 3 (d), the state shown in (e) of and 5 (b).

  As described above, when the lock fitting 7 is fitted from the open posture to the end of the opening stopper rod 4 and closed, the inward projections 21 and 21 on the lock fitting 7 side are protruded outward 18 on the stopper rod 4 side. , 18 is not unlocked unless a person forcibly returns the lock fitting 7 to the open position, so that the lock fitting 7 can be reliably maintained in the locked state. When the lock fitting 7 is closed, there is a “click” feel when the inward projection 21 on the lock fitting 7 side gets over the outward projection 18 on the stop guard 4 side. It can be confirmed that 7 is securely locked in the closed position.

  In this embodiment, as shown in FIG. 8 (a), the engaging grooves 14 of the lock fitting 7 are formed in both the left and right side wall portions 7a and 7a, respectively. Of the engaging grooves 14 and 14 of the left and right side wall portions 7 a and 7 a, the engaging groove 14 of the side wall portions 7 a and 7 a on the side facing the opening stopper metal fitting 9 is engaged with the pin 13. 4 and 5 are engaging grooves 14 formed on the side wall 7a opposite to the side wall 7a on the side actually engaged with the pin 13. As shown in FIG. As shown in this embodiment, by forming the engaging grooves 14 in the left and right side walls 7a and 7a of the lock fitting 7, respectively, as shown in FIG. In any case, the same lock fitting 7 can be used for any of the four, so that there is a production compatibility. Further, in this embodiment, as shown in FIG. 6 (a), the pin insertion hole 11 provided in one side surface portion of the front end portion of each opening guard 4 is connected to the pin on the other side surface portion. A through hole 11 a having the same diameter as that of the pin insertion hole 11 is provided at a position facing the insertion hole 11. The through hole 11a can be used as a monitoring hole for confirming whether the pin 13 with the locking head 12 is securely inserted into the pin insertion hole 11 on the one side surface portion. In this case, since the pin insertion hole 11 and the through hole 11a have the same hole diameter, there is a compatibility in manufacturing that can be used for any one of the left and right opening stoppers 4 and 4.

  As shown in FIG. 5 (b), after the lock fitting 7 is locked in the closed position and then unlocked, it will be described with reference to FIGS. 4 (a) and 4 (b) to FIG. 5 (a) and 5 (b). The reverse operation of the above operation may be performed. When performing the locking operation and unlocking operation of the lock fitting 7, the operation can be quickly and easily performed by grasping the opening / closing operation piece 23 provided on the distal end side of the upper wall portion 7b.

  Further, the protrusions 18 and 18 projecting from the openings 16 on both side surfaces of the front end of the opening stopper rod 4 have a shape in which the lock fitting 7 is easily inserted and is difficult to be removed, that is, FIG. 6B and FIG. As shown in (e) of FIG. 9 and (a) of FIG. 9, the front portion 18a has a gentle upward slope, the peak 18b is parallel, and the last portion is a step 18c.

(a) is a front view of a stepladder according to the present invention, and (b) is a side view. (a) is the enlarged view of the part shown by the arrow A of (a) of FIG. 1, (b) is a cross-sectional view of the part shown to (a). (a) is an enlarged view of the part indicated by arrow B in FIG. 1 (a), (b) is a cross-sectional view of the part shown in (a), (c) a cross-sectional view taken along the line CC of (a), d) is a longitudinal cross-sectional view of the lock fitting and the locking stopper in the locked closed position, and (e) is a cross-sectional view taken along the line DD of (d). (a), (b) is explanatory drawing which shows the fixing method of an opening | mouth stopper | sticker hook front-end | tip part. (a) and (b) are explanatory diagrams showing the fixing method. (a) is a perspective view showing a state in which the end cap is about to be inserted into the front end portion of the locking stopper, and (b) is a perspective view showing the tip portion of the opening stopper in a state where the end cap is inserted and fixed. It is. (a) is a perspective view showing an end cap, (b) is a front view, (c) is a plan view, (d) is a side view, and (e) is a bottom view. (a) is a perspective view showing a lock fitting, and (b) is a sectional view taken along line XX of (a). (a) is a front view showing a state in which the lock fitting is in an open posture with respect to the front end of the locking rod, and (b) is a front view in a state in which the lock fitting is in a closed posture with respect to the leading end of the locking rod. .

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Stepladder 2 Ladder-like leg 4 Unlocking bar 5 Ladder-like leg side frame 6 Ladder-like leg traverse 7 Lock metal fitting 10 Axis 11 Pin insertion hole 12 Locking head 13 Locking head pin 14 Unlocking bar 15 End cap 18 made of synthetic resin Outward projection 21 Inward projection

Claims (4)

A pair of locking rods are placed in an X-shape on both legs of the stepladder formed by pivoting the tops of a pair of ladder-shaped legs, and the base ends of the double locking rods are pivotally attached to the upper sides of both legs. And a stepladder prevention device for fixing the respective leading ends of the double-opening stop rods to the lower sides of both legs,
A pin insertion hole is provided in the side of the tip of each locking stop, and a pin with a locking head that projects through the head through the pin insertion hole of the locking stop is provided on the lower side of each leg. A locking bracket is pivotally attached to the top end of the stopper rod so that it opens and closes in a closed position that overlaps the opening stopper rod in parallel and a lower posture that opens up from the opening stopper rod. Ri Na provided engaging Hamamizo for locking by Kakarihama from above relative to said pin when going closed from the attitude open the lock fitting,
Further, the opening stopper is made of a square tube, and an end cap made of synthetic resin is fitted and fixed to the tip of the stopper, and the outward projecting portions protruding from both side surfaces of the end cap are opened. The lock fitting is formed in a U-shape that can be fitted to and removed from the opening-stopper by the left and right side wall parts and the upper wall part, and an inward projection on the inner side tip side of the left and right side wall parts. When the lock fitting is closed from the open position, the inward projections on the left and right side walls are directed outwardly from the end cap. A stepladder stop device that locks by going over the protrusion .   If the hole diameter of the pin insertion hole is d1, the outer diameter of the locking head is d2, the groove width of the engagement groove is d3, and the outer diameter of the pin is d4, d1> d2> d3> d4. The step opener for a stepladder according to claim 1.   3. The through hole is provided at a position opposite to the pin insertion hole on the other side surface with respect to the pin insertion hole provided on one side surface of the front end portion of each opening stopper. The step opener for the stepladder described in 1. 2. The step opening preventing device for a stepladder according to claim 1 , wherein an opening / closing operation piece extends from the tip of the upper wall portion of the lock fitting.

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