JP6368220B2 - Telescopic leg device in aerial work equipment - Google Patents

Description

TECHNICAL FIELD The present invention relates to a telescopic leg device in an aerial work device such as a stepladder, a work table, or a ladder.

2. Description of the Related Art Conventionally, a leg of an altitude work device such as a stepladder is composed of a main leg and telescopic legs that are slidably fitted to the main leg, and are arranged in a row in the sliding direction on the telescopic legs. And a lock mechanism for releasably engaging with the teeth of the rack is provided at the fixing portion of the main leg.

Therefore, by unlocking the lock mechanism and sliding the telescopic legs, the operator can get the boarding position at a desired height if the lock mechanism is locked in a state where the leg body has a predetermined length. The aerial work equipment can be used in the state.

JP 2009-121130 A

By the way, for example, in the case of a stepladder provided with telescopic leg devices on four pedestals as in Patent Document 1, the telescopic legs can be expanded and contracted so that each pedestal has a desired length. There is an advantage that it can be stably installed on an irregular ground.

However, there is no means for easily confirming the expansion / contraction length when expanding / contracting each expansion / contraction leg so that a plurality of pedestals have a desired length. There is inconvenience that you have to set.

Furthermore, for example, even when the stepladder is installed on a leveling surface with no difference in height, if the telescopic legs are not expanded and contracted so that the four pillars have the same length, the stepladder tilts in the installed state, etc. There is a problem that becomes unstable. Therefore, also in this case, there is an inconvenience that the extension / contraction length must be set while repeating trial and error.

The present invention solves the above-described problem and provides an apparatus that allows an operator to easily confirm the expansion / contraction length by visual inspection when an operator sets the pedestal column to a predetermined length by extending / contracting the expansion / contraction leg. It is to provide.

Therefore, the present invention is configured as a means comprising a main leg and telescopic legs slidably fitted to the main leg, and arranged in one of the main legs and the telescopic legs in the sliding direction. A rack having a large number of teeth is provided, and a lock mechanism is provided for releasably engaging with the rack teeth from a fixed portion fixed to the other, and the rack teeth are arranged to be visible from the outside. In the telescopic leg device for an aerial work device, the rack is provided with a predetermined interval including a plurality of teeth among a groove formed between adjacent teeth and a tooth arranged through the groove. Marking means is provided in the arranged specific groove portion, and the mark means is provided with an identification display visually identified from a groove portion and a tooth other than the specific groove portion.

In a preferred embodiment of the present invention, the rack is disposed in the longitudinal direction of the band, with a band-shaped unit rack member in which teeth are disposed at both ends and a plurality of teeth are arranged between the teeth at both ends via a groove. A spacer member interposed between the plurality of unit rack members, and a concave portion that is positioned between mutually facing teeth of the plurality of unit rack members and constitutes the specific groove portion by the spacer member. And the marking means is configured by providing an identification display on the spacer member.

Furthermore, in a preferred embodiment of the present invention, a housing groove is formed in the longitudinal direction of the telescopic leg, and the rack is fitted to the telescopic leg with the rack fitted in the housing groove. Inwardly extending flanges from both side edges, the band-shaped unit rack is fitted in the receiving groove, and both ends of teeth in the band width direction are fitted inside the flange, The spacer member forms a bulge at both ends of the bottom plate that forms the bottom of the recess, and the bulge is fitted inside the flange.

According to the first aspect of the present invention, in the telescopic leg device provided with the rack 8 and the lock mechanism 10, the teeth 7 of the rack 8 are arranged so as to be visible from the outside, and the predetermined number includes the plurality of teeth 7 of the rack 8. Since the marking means 19 is provided in the specific groove portion 18a arranged at the interval L and the identification means for visually identifying the groove portion 18 and the teeth 7 other than the specific groove portion 18a is configured, the operator can extend and retract the leg. When the leg column 1c is set to a predetermined length by expanding and contracting 6, there is an effect that the expansion and contraction length can be easily confirmed by visually observing the marking means 19.

The locking mechanism 10 is configured to be engaged with the teeth 7 of the rack 8 and is not engaged with the groove portion 18. Therefore, by providing the marker means 19 in the specific groove portion 18 a, the marker means 19 is locked. The mechanism 10 is not damaged by the engagement / disengagement of the mechanism 10 so that it is difficult to visually recognize the mechanism 10.

According to the second aspect of the present invention, the rack 8 includes a band-shaped unit rack member 8U having a predetermined number of teeth 7 and a plurality of unit rack members 8U and 8U arranged in the band longitudinal direction. The marker member 19 is formed by the spacer member 27 interposed therebetween. Accordingly, if the rack 8 is extended by alternately arranging the unit rack members 8U and the spacer members 27, the plurality of labeling means 19 are arranged at predetermined equal intervals. Can be provided as a scale that can be confirmed at regular intervals.

In addition, by providing the teeth 7a at both ends of the unit rack member 8U, all the teeth 7 of the rack 8 locked to the lock mechanism 10 are formed by the unit rack member 8U. Therefore, for example, when the teeth 7 are provided on the spacer member 27 formed of a small piece, when a load is applied in a state of being engaged with the lock mechanism 10, there is a possibility that the spacer member 27 is easily damaged and falls off from the receiving groove 16. On the other hand, since the spacer member 27 is not provided with teeth and constitutes only the specific groove portion 18a, there is no risk of damage as described above, and the durability of the rack 8 is satisfied.

According to the third aspect of the present invention, in the housing groove 16 provided with the flange 31, the unit rack member 8 </ b> U has both end portions of the teeth 7 fitted inside the flange 31, and the spacer member 27. The raised portion 29 is fitted inside the flange 31. Therefore, the unit rack member 8U and the spacer member 27 are fixed so as not to move vertically and horizontally inside the housing groove 16 even if they are not fixed to the telescopic legs 6 with a fixing tool or the like. It works well.

It is a perspective view which shows the stepladder as an example of the aerial work apparatus provided with the expansion-contraction leg apparatus of this invention. (A) is sectional drawing which shows the pedestal of the stepladder shown in FIG. 1, (B) is an AA sectional enlarged view. It is sectional drawing which shows the effect | action of the rack and locking mechanism in an expansion-contraction leg apparatus, and shows the state which latched the locking mechanism to the rack. It is sectional drawing which shows the effect | action of the rack and locking mechanism in an expansion-contraction leg apparatus, and shows the state which the latching of the locking mechanism was cancelled | released. It is a perspective view which shows the decomposition | disassembly state of an expansion-contraction leg and a rack. 1A is a perspective view showing a state in which a unit rack member and a spacer member are separated from each other, and FIG. The unit rack, the spacer member, and the extendable leg are shown. (A) is a perspective view showing the extendable leg in a state in which the unit rack and the spacer member are inserted in a partially broken state, and (B) shows the accommodation groove of the extendable leg. Sectional drawing, (C) is sectional drawing of the part which inserted the unit rack in the accommodation groove, (D) is sectional drawing of the part which inserted the spacer member in the accommodation groove.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

The drawing shows a stepladder as an example of an aerial work apparatus. However, it is understood that the present invention is not limited to a stepladder, and may be an altitude work device for an operator to work at a high place, such as a work table or a ladder, and can be widely implemented. I want.

The stepladder illustrated in FIG. 1 includes a first leg 1a and a second leg 1b arranged on the left and right, and the upper ends of both legs 1a and 1b are pivoted to each other by a pivoting means (not shown). By doing so, there is provided a detachable locking device 2 which is configured to be openable and closable and which is connected in an open state.

The first leg 1a and the second leg 1b are formed in a ladder shape with a top plate 4 and a plurality of step bars 5a and 5b provided between a pair of leg posts 1c and 1c, respectively. The main leg 3 and the extendable leg 6 slidably fitted into the main leg 3 constitute an extendable leg device.

As shown in FIG. 2, the telescopic leg 6 is provided with a belt-like rack 8 having a large number of teeth 7 arranged in the sliding direction. The main leg 3 is fixed to the main leg 3. A lock mechanism 10 is provided for releasably locking the fixed portion 9 to the teeth 7 of the rack 8. In the case of the example shown in the figure, a lock mechanism 10 is provided with the lower side rail 5a as a fixed portion 9.

The main leg 3 is made of an aluminum extruded material, is formed by a cross-sectional groove-shaped member that opens toward the inside of the pedestal 1c, and a guide cylinder 11 is fixed to a lower end portion of the main leg 3, A sliding path 12 is formed from the guide cylinder 11 along the inside of the main leg 3. At this time, the step bars 5a and 5b are fixed to the outer surface of the main leg 3 via brackets 11a and 11b so as not to enter the groove opening of the main leg 3 and interfere with the sliding path 12. Has been.

The telescopic legs 6 are made of an extruded material of aluminum, are formed of a hollow cylindrical member, have a grounding seat 14 fixed to a lower end portion thereof, and are inserted into the sliding path 12 by inserting the guide cylindrical body 11. It is slidably inserted.

The telescopic leg 6 includes an inner wall 15 exposed from the groove opening of the main leg 3, and the rack 8 is fitted and fixed in a receiving groove 16 that is recessed over the entire length of the inner wall 15. An end cap 17 is fixed to the upper end of the telescopic leg 6. Therefore, as shown in FIG. 1, the rack 8 is arranged so that the teeth 7 can be visually recognized from the outside.

Regarding the rack 8 and the lock mechanism 10, the illustrated embodiment shows a configuration in which the rack 8 is provided on the telescopic leg 6 and the lock mechanism 10 is provided on the fixing portion 9 of the main leg 3. May be provided on the main leg 3, and the lock mechanism 10 may be provided on the fixing portion of the telescopic leg 6. In short, the main leg 3 and the telescopic leg 6 are relatively slidably fitted in the telescopic direction, and the rack 8 is provided. What is necessary is just to arrange | position so that it can visually recognize from the outside.

As shown in FIG. 3, the rack 8 has a groove portion 18 formed between adjacent teeth 7, 7, and the teeth 7 are arranged at predetermined pitch intervals through the groove portion 18. The marking means 19 is provided in a specific groove portion 18a arranged with a predetermined interval L including.

The marking means 19 is provided with an identification display that can be easily identified visually from a portion of the surface of the rack 8 other than the marking means 19, that is, from the other groove portions 18 and the teeth 7. For example, when the rack 8 is made of aluminum, such identification display can be configured by coloring that allows the specific groove 18a to be easily identified from the metal color of aluminum. At this time, the identification display by color can be easily performed by selecting from the brightness, hue, etc. of the color and making only the specific groove portion 18a different from the other portions. In addition, the identification display may be formed by displaying not only coloring but also graphics, characters, numbers, etc., and the means for identification is not limited.

In the case of the illustrated embodiment, the locking mechanism 10 pivotally supports a locking member 21 on a housing 20 fixed to the fixing portion 9, and rotates the locking member 21 in the forward rotation direction (clock hand shown in the figure). By rotating the locking member 21 in the reverse direction (counterclockwise direction) to move away from the teeth 7 of the rack 8 to be locked. An actuator 22 that rotates the locking member 21 is provided.

As shown in FIG. 3, the actuator 22 is provided in the housing 20 so as to be movable forward and backward toward the locking member 21, and is always urged toward the forward direction F by a spring 23. Accordingly, in this state, the actuator 22 rotates the locking member 21 in the normal rotation direction to lock the claw 21 a of the locking member 21 to the tooth 7 of the rack 8. The locking member 21 locks the claw 21a with the tooth 7 of the rack 8, but is configured not to rotate until it comes into contact with the groove portion 18. Therefore, a stopper 24 for stopping the rotation is provided. It has been. In the case of the illustrated example, the stopper 24 is formed on a part of the outer peripheral edge of the locking member 21, and stops the locking member 21 by contacting the housing 20. Thereby, even when the claw 21a of the locking member 21 enters toward the specific groove 18a, there is no possibility that the claw 21a is damaged by coming into contact with the marking means 19 of the groove 18a.

As shown in FIG. 4, when the actuator 22 is moved in the backward direction R against the spring 23 by placing a finger on the finger hooking portion 25, the locking member 21 is reversed via the interlocking connecting portion 26, 21a is separated from the teeth 7 of the rack 8 to release the lock. Therefore, the extensible leg 6 can be slid in this state. Note that after the extensible leg 6 is slid to the desired position with respect to the main leg 3, the actuator 22 is advanced by the spring 23 when the finger hooking portion 25 is released, and the engagement member 21 and the rack 8 are engaged. Is automatically stopped.

In the case of the embodiment shown in FIGS. 3 and 4, the extendable legs 6 are extended downward from the guide cylinder 11 fixed to the lower end portion of the main leg 3, and the labeling means 19 of the rack 8 is attached together with the extendable legs 6. Since it is exposed, the operator can see the position of the marking means 19 that appears immediately below the guide cylinder 11 with the guide cylinder 11 as a reference position, and to what extent the telescopic leg 6 has been extended or contracted. Can be easily recognized. The reference position relatively compared with the position of the marking means 19 is not limited to the guide cylinder 11, and may be, for example, the upper surface of the step rail 5 a, and another member can be used. An index indicating the reference position may be provided by applying a figure or the like to the three easy-to-see positions.

FIGS. 5 to 7 show a preferred embodiment relating to the rack 8 provided with the telescopic legs 6 and the marking means 19.

The rack 8 includes a plurality of band-shaped unit rack members 8U and a spacer member 27 interposed between the plurality of unit rack members 8U and 8U arranged in the band longitudinal direction. The unit rack member 8U is formed of a strip-shaped member in which teeth 7a, 7a are arranged at both ends, and a plurality of teeth 7 are arranged between the teeth 7a, 7a at both ends via a groove portion 18. . In the case of the illustrated embodiment, as shown in FIG. 5, end plates 28 and 29 are provided that extend in both end directions from the unit rack member 8 </ b> U that is arranged in the band longitudinal direction. The end plates 28 and 29 are provided with a rack portion 8 a having teeth 7 and groove portions 18 connected to the unit rack member 8 U via the spacer member 27. Therefore, the spacer 8 and the unit rack member 8U are alternately arranged between the end plates 28 and 29, whereby the rack 8 having a width W is formed, and the rack 8 is formed in the accommodating groove 16 of the telescopic leg 6. The end plates 28 and 29 are inserted into the housing groove 16 and fixed to the telescopic leg 6 by a fixing tool 30 such as a rivet. Therefore, the unit rack member 8U and the spacer member 27 are not fixed by a dedicated fixing tool, and are positioned between the fixed end plates 28 and 29 and fixed inside the receiving groove 16. doing.

As shown in FIG. 6, the unit rack member 8 </ b> U has teeth 7 having a height h <b> 1 projecting over a width W on a plate-like portion having a thickness t <b> 1 having the width W, and adjacent teeth 7. , 7 is formed with a groove portion 18 having a groove width s1. On the other hand, the spacer member 27 has a height equal to the width W, a plate width s2 equal to the groove width s1, and a thickness t2 equal to the thickness t1 on both ends of the bottom plate portion 28. Raised portions 29 and 29 having a height h2 equal to the height h1 are formed, and a recessed portion 30 is formed between the raised portions 29 and 29 and has the upper surface of the bottom plate portion 28 as a bottom portion. In the present specification, the phrase “equal” is not a strict meaning, and the rack 8 constituted by the combination of the unit rack member 8U and the spacer member 27 has the same function as the normal rack in relation to the lock mechanism 10. Therefore, it should be understood that it has a functional meaning.

The unit rack member 8U can be formed, for example, by cutting an extruded material formed by extrusion of aluminum so as to have the width W. For example, the spacer member 27 can be formed of a synthetic resin, and the marking means 19 can be formed by coloring a resin material with a pigment in a clear color. Of course, the marker member 19 may be formed by forming the spacer member 27 from other materials and coloring the surface.

As shown in FIG. 7B, the accommodating groove 16 of the telescopic leg 6 has a groove width Wx equal to the width W and a depth D equal to the sum of the thickness t1 and the height h1. Flange 31, 31 is extended inward from both side edges of the groove opening.

As described above, the end plates 28 and 29 and the unit rack members 8U and the spacer members 27 are alternately arranged between the end plates 28 and 29 in the longitudinal direction of the belt, and the rack 8 is configured by bringing them into contact with each other. The rack 8 is inserted and fixed in the receiving groove 16.

In this state, the unit rack member 8U fits both ends of the teeth 7 inside the flange 31 as shown in FIG. The spacer member 27 fits the raised portion 29 inside the flange 31. Therefore, the unit rack member 8U and the spacer member 27 are fixed so as not to move vertically and horizontally inside the housing groove 16 even if they are not fixed to the telescopic legs 6 with a fixing tool or the like. It works well.

The rack 8 includes a band-shaped unit rack member 8U having teeth 7 having a predetermined number of teeth and a spacer member 27 interposed between the plurality of unit rack members 8U and 8U arranged in the longitudinal direction of the band. The marking means 19 is formed by the spacer member 27 formed. Accordingly, if the rack 8 is extended by alternately arranging the unit rack members 8U and the spacer members 27, the plurality of labeling means 19 are arranged at predetermined equal intervals. Can be provided as a scale that can be confirmed at regular intervals.

In addition, by providing the teeth 7a at both ends of the unit rack member 8U, all the teeth 7 of the rack 8 locked to the lock mechanism 10 are formed by the unit rack member 8U. Therefore, for example, when the teeth 7 are provided on the spacer member 27 formed of a small piece, when a load is applied in a state of being engaged with the lock mechanism 10, there is a possibility that the spacer member 27 is easily damaged and falls off from the receiving groove 16. On the other hand, since the spacer member 27 is not provided with teeth and constitutes only the specific groove portion 18a, there is no risk of damage as described above, and the durability of the rack 8 is satisfied.

DESCRIPTION OF SYMBOLS 1a 1st main leg 1b 2nd main leg 1c Pillar 2 Opening stop device 3 Main leg 4 Top plate 5a, 5b Foot 6 Telescopic leg 7 Rack teeth 7a Both-end teeth 8 Rack 8U Unit rack member 9 Fixing part 10 Lock Mechanism 11 Guide cylinder 12 Sliding path 13a, 13b Bracket 14 Grounding seat 15 Inner side wall 16 of telescopic leg Housing groove 17 End cap 18 Rack groove 18a Specific groove 19 Marking means 20 Housing 21 Locking member 21a Claw 22 Actuator 23 Spring 24 Stopper 25 Finger hooking portion 26 Interlocking connecting portion 27 Spacer member 28 Bottom plate portion 29 Raised portion 30 Recessed portion 31 Flange

Claims (3)

A main leg (3) and a telescopic leg (6) slidably fitted to the main leg, and a plurality of teeth arranged in the sliding direction on one of the main leg and the telescopic leg ( A rack (8) having 7) is provided, and a lock mechanism (10) is provided for releasably engaging with a tooth of the rack from a fixed portion fixed to the other, so that the rack teeth can be visually recognized from the outside. In the telescopic leg device of the aerial work device that is arranged,
The rack (8) includes a groove (18) formed between adjacent teeth (7) and (7), and a plurality of teeth (7) among teeth arranged via the groove. Marking means (19) is provided in specific grooves (18a) arranged at intervals (L),
The sign means (19) is provided with an identification display visually identified from the groove (18) and the tooth (7) other than the specific groove (18a), and the telescopic leg in an aerial work device characterized in that apparatus. The rack (8) has teeth (7a, 7a) arranged at both ends, and a band-shaped unit rack member (8U) in which a plurality of teeth (7) are arranged via grooves (18) between the teeth at both ends. And a spacer member (27) interposed between the plurality of unit rack members (8U) (8U) arranged in the belt longitudinal direction,
The spacer member (27) is located between the mutually opposing teeth (7a) and (7a) of the plurality of unit rack members (8U) (8U), and is a recess (30) constituting the specific groove (18a). )
The telescopic leg device in an aerial work device according to claim 1, wherein the marker means (19) is configured by providing an identification display on the spacer member (27). In the configuration in which the accommodation groove (16) is formed in the longitudinal direction of the extensible leg (6), and the rack (8) is fitted in the accommodation groove and fixed to the extensible leg.
The housing groove (16) extends inward flanges (31) from both side edges of the groove opening,
The band-shaped unit rack (8U) is fitted in the receiving groove, and both ends of the teeth (7) in the band width direction are fitted inside the flange (31),
The spacer member (27) is formed with raised portions (29) at both ends of a bottom plate portion (28) constituting the bottom portion of the recessed portion (30), and the raised portions (29) are formed inside the flange (31). The telescopic leg device in an aerial work device according to claim 2, wherein the telescopic leg device is fitted.

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