GB1599636A - Ladders - Google Patents

Description

(54) IMPROVEMENTS RELATING TO LADDERS (71) I, SIMON NICHOLAS RELTON, a British subject of Forge Cottage, Linton, near Maidstone, Kent, do hereby declare the invention, for which I pray that a patent may be granted to me, and the method by which it is to be performed, to be particularly described in and by the following statement:- This invention relates to ladders and more particularly to a ladder which, in addition to its use as a normal ladder, is adapted to be easily and quickly concerted into forms suitable for use for a variety of other purposes such as a pair of steps or a trestle.

According to the invention, a ladder comprises at least three longitudinal sections pivotally connected together, each section comprising a pair of stiles having rungs therebetween, and means for enabling any two sections to be fixed at any one of a plurality of angles with respect to each other, said means comprising a first member secured to the end of one of an adjacent pair of said stiles and formed with a central aperture for reception of a pivot pin and a plurality of circular apertures at equal distances from said central aperture, and a second member secured to the end of the other of said pair of stiles and formed with a central aperture for reception of said pivot pin and a circular aperture at a distance from said central aperture such that, on rotation of the sections with respect to each other about said pivot pin, the aperture in said second member may be brought in coincidence with one of the apertures in said first member, and locking means comprising a locking pin adapted to be passed through said coincident apertures.

Said locking means may comprise a spring-loaded lever pivotally mounted on one of said apertured members, one end of said lever being formed to engage said locking pin in order to remove it by rocking of said lever.

The stiles may consist of I-section members, the webs of which are engaged and secured in slots in said apertured members.

One embodiment of the invention will now be described by way of example with reference to the accompanying drawings, in which: Figures 1 and 2 are corresponding plan and elevational views of the hinge and locking mechanism, Figures 3 and 4 are corresponding plan and elevational views of one of the members of the hinge joint, Figures 5 and 6 are corresponding plan and elevational views of the other member of the hinge joint, and Figures 7 to 10 are diagrammatic views illustrating various uses of the ladder.

Referring first to Figures 1 to 6, the stiles 10 of the ladder consist of I-section members which are connected to hinge members as hereinafter described. A hinge joint between two adjacent sections of the ladder is constituted by a pair of members 11 and 12 as illustrated in Figures 1 and 2 and Figures 3 and 4 respectively.

The hinge member 11 comprises a circular plate 13 having a central aperture 14 for receiving a pivot pin and three off-set apertures 15 for receiving a locking pin referred to hereinafter. If desired, only two off-set apertures 15 may be provided. Hinge member 11 also comprises a portion 16 having an aperture 17 therein for receiving a ladder rung 18, and a plate 19 attached to portion 16 and having a slot 20 therein for receiving the web 21 of a stile 10 which is secured therein by means of bolts 22.

The hinge member 12 comprises a bifurcated part-circular portion 23 having central apertures 24 through its arms for receiving said pivot pin and an off-set aperture 25 for receiving said locking pin. The hinge member 12 also comprises a plate 26 having a slot 27 therein for receiving the web 21 of a stile 10 which is secured therein by means of bolts 22.

The plate 26 is also provided with a bracket 28 having ears 29 between which is pivotally mounted a lever 30 by means of a pivot pin 31. The lever 30 has a knurled operating knob 32 at one end thereof and is bifurcated at the other end to form arms 33. A torsion spring 34 serves to maintain the lever 30 in the locking position as described below.

The hinge members 11 and 12 are as sembled as illustrated in Figures 1 and 2 by inserting the plate 13 of member 11 into the bifurcated portion 23 of the plate 12 so that the apertures 14 and 24 coincide for the passage therethrough of a pivot pin.

When adjacent sections of the ladder are disposed in alignment, one of the off-set apertures 15 in the plate 13 of member 11 is coincident with the off-set aperture 25 in the bifurcated portion 23 of member 12 and are locked in this position by means of a pin 35 passed through apertures 15 and 25. The arms 33 of the lever 30 are adapted to engage a shank 36 of pin 35 and the pin 35 may be removed by pivoting the lever 30 by pressing on the knob 32 so that the arms 33 bear upon the head 37 of the pin 35.

When it is desired to position adjacent sections of the ladder at an angle to each other, the locking pin 35 is removed and members 11 and 12 are rotated with respect to each other until the apertures 25 in member 12 are coincident with another of the off-set apertures 15 in member 11, and the pin 35 re-inserted.

It will be understood that the ladder is not hinged at the position of every rung and, except at the hinge positions, the rungs 18 are inserted in apertures in the webs of the stiles 10.

Various uses of the ladder according to the invention are diagrammatically illustrated in Figures 7 to 10.

Thus, Figure 7 shows the ladder in use as an ordinary ladder leaning against a wall.

Figure 8 shows the ladder in use as a pair of steps by pivoting the stiles at hinge positions adjacent their mid-point. Figure 9 shows the ladder adapted for use as a trestle with equal end portions of the stiles brought into an inclined position with respect to the central portion thereof. Figure 10 shows how the ladder may be used to provide a horizontal working surface supported on stairs or steps by pivotting end portions of unequal length of the stiles about an inner portion thereof.

The ladder according to the invention may be made of any suitable material such as aluminium or a plastics material having the necessary strength and impact resistance.

WHAT I CLAIM IS: 1. A ladder comprising at least three longitudinal sections pivotally connected together, each section comprising a pair of stiles having rungs therebetween, and means for enabling any two sections to be fixed at any one of a plurality of angles with respect to each other, said means comprising a first member secured to the end of one of an adjacent pair of said stiles and formed with a central aperture for reception of a pivot pin and a plurality of circular apertures at equal distances from said central aperture, and a second member secured to the end of the other of said pair of stiles and formed with a central aperture for reception of said pivot pin and a circular aperture at a distance from said central aperture such that, on rotation of the sections with respect to each other about said pivot pin, the aperture in said second member may be brought in coincidence with one of the apertures in said first member, and locking means comprising a locking pin adapted to be passed through said coincident apertures.

2. A ladder according to claim 1, wherein said locking means comprises a springloaded lever pivotally mounted on one of said apertured members, one end of said lever being formed to engage said locking pin in order to remove it by rocking of said lever.

3. A ladder according to any of the preceding claims, wherein the stiles consist of I-section members, the webs of which are engaged and secured in slots in said apertured members.

4. A ladder according to any of claims 1 to 3 wherein said first member comprises a slotted portion receiving a stile, an apertured portion receiving a rung and a portion of off-set from said apertured portion and formed with a central aperture receiving a hinge pin and with a plurality of apertures off-set from said central aperture, and said second member comprises a slotted portion receiving a stile and a portion off-set from said slotted portion and formed with a central aperture coinciding with the corresponding aperture in the first member and an aperture off-set from said central aperture so that it may be brought into coincidence with one of the off-set apertures in said first member.

5. A ladder substantially as hereinbefore described with reference to the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (5)

**WARNING** start of CLMS field may overlap end of DESC **. sembled as illustrated in Figures 1 and 2 by inserting the plate 13 of member 11 into the bifurcated portion 23 of the plate 12 so that the apertures 14 and 24 coincide for the passage therethrough of a pivot pin. When adjacent sections of the ladder are disposed in alignment, one of the off-set apertures 15 in the plate 13 of member 11 is coincident with the off-set aperture 25 in the bifurcated portion 23 of member 12 and are locked in this position by means of a pin 35 passed through apertures 15 and 25. The arms 33 of the lever 30 are adapted to engage a shank 36 of pin 35 and the pin 35 may be removed by pivoting the lever 30 by pressing on the knob 32 so that the arms 33 bear upon the head 37 of the pin 35. When it is desired to position adjacent sections of the ladder at an angle to each other, the locking pin 35 is removed and members 11 and 12 are rotated with respect to each other until the apertures 25 in member 12 are coincident with another of the off-set apertures 15 in member 11, and the pin 35 re-inserted. It will be understood that the ladder is not hinged at the position of every rung and, except at the hinge positions, the rungs 18 are inserted in apertures in the webs of the stiles 10. Various uses of the ladder according to the invention are diagrammatically illustrated in Figures 7 to 10. Thus, Figure 7 shows the ladder in use as an ordinary ladder leaning against a wall. Figure 8 shows the ladder in use as a pair of steps by pivoting the stiles at hinge positions adjacent their mid-point. Figure 9 shows the ladder adapted for use as a trestle with equal end portions of the stiles brought into an inclined position with respect to the central portion thereof. Figure 10 shows how the ladder may be used to provide a horizontal working surface supported on stairs or steps by pivotting end portions of unequal length of the stiles about an inner portion thereof. The ladder according to the invention may be made of any suitable material such as aluminium or a plastics material having the necessary strength and impact resistance. WHAT I CLAIM IS:

1. A ladder comprising at least three longitudinal sections pivotally connected together, each section comprising a pair of stiles having rungs therebetween, and means for enabling any two sections to be fixed at any one of a plurality of angles with respect to each other, said means comprising a first member secured to the end of one of an adjacent pair of said stiles and formed with a central aperture for reception of a pivot pin and a plurality of circular apertures at equal distances from said central aperture, and a second member secured to the end of the other of said pair of stiles and formed with a central aperture for reception of said pivot pin and a circular aperture at a distance from said central aperture such that, on rotation of the sections with respect to each other about said pivot pin, the aperture in said second member may be brought in coincidence with one of the apertures in said first member, and locking means comprising a locking pin adapted to be passed through said coincident apertures.

2. A ladder according to claim 1, wherein said locking means comprises a springloaded lever pivotally mounted on one of said apertured members, one end of said lever being formed to engage said locking pin in order to remove it by rocking of said lever.

3. A ladder according to any of the preceding claims, wherein the stiles consist of I-section members, the webs of which are engaged and secured in slots in said apertured members.

4. A ladder according to any of claims 1 to 3 wherein said first member comprises a slotted portion receiving a stile, an apertured portion receiving a rung and a portion of off-set from said apertured portion and formed with a central aperture receiving a hinge pin and with a plurality of apertures off-set from said central aperture, and said second member comprises a slotted portion receiving a stile and a portion off-set from said slotted portion and formed with a central aperture coinciding with the corresponding aperture in the first member and an aperture off-set from said central aperture so that it may be brought into coincidence with one of the off-set apertures in said first member.

5. A ladder substantially as hereinbefore described with reference to the accompanying drawings.