GB2205890A

GB2205890A - Frame, such as ladder, mounted on a guide bar

Info

Publication number: GB2205890A
Application number: GB08813707A
Authority: GB
Inventors: Ture Hedstrom
Original assignee: Individual
Current assignee: Individual
Priority date: 1987-06-17
Filing date: 1988-06-09
Publication date: 1988-12-21
Also published as: SE8702541L; NO168785C; FI882883A0; NO168785B; NO882604L; FI882883A; NO882604D0; SE8702541D0; GB8813707D0; SE461162B

Abstract

The present invention relates to a guide arrangement for a frame construction 10, such as a ladder structure, a platform or the like, which is mounted for linear movement along preferably a single guide bar 7 and the span of which is such that the frame construction will rest against and be supported by at least one rail 8 extending parallel with the guide bar, through the intermediary of runners or rollers (11). The arrangement further comprises two guide members 35 which are mutually spaced apart along the guide bar 7 and which are joined together and to the frame construction (10), such that the frame construction takes a predetermined angular portion (perpendicular) relative to the longitudinal extension of the guide bar 7. Each of these guide members 37 has lightly journalled thereon at least three rolling surfaces 36, 37, 38 which are positioned so that the guide bar 7 will pass therebetween, to hold the frame construction 10 in running engagement with the guide bar 7. <IMAGE>

Description

A guide arrangement for a frame construction intended for linear movement along a guide bar.

TECHNICAL FIELD The. present invention relates to a guide arrangement for co-action with a frame construction which is intended for linear movement along solely one guide bar, despite the span of the frame construction away from the guide bar being such as to necessitate supporting the frame structure on at least one rail extending parallel with said guide bar, through the intermediary of runners or support wheels.

The invention finds particular application in such frame constructions as ladder structures, platform structures, or like structures.

BACKGROUND PRIOR ART It is known to arrange a ladder structure on an external roof surface for linear movement therealong on a guide bar and on one or more runners or rails, for facilitating such work as the cleaning of windows, etc.

One difficulty with the constructions known hitherto is that because of its considerable length the ladder is liable to become stuck or firmly stuck as a result of the torque which is generated by the force applied to the ladder in order to move it linearly along the guide bar, thereby requiring the provision of separate guide means.

This force is applied at a point which is far remote from the guide bar.

Movement of the ladder along an upper guide bar and guide rails spaced therebeneath is normally effected by applying a force solely to the lowermost end of the ladder distal from the guide bar.

Practical experiences have shown that highly rigid, or inflexible, and readily movable guide means are needed to cooperate with the guide bar in order to be able to move a long ladder structure along a single guide bar without the ladder sticking or jamming.

SUMMARY OF THE INVENTION TECHNICAL PROBLEMS When viewing the state of the present prior art, as described above, it will be seen that a technical problem resides in the ability to present a structurally simple guide arrangement by means of which a ladder structure or platform structure can be moved linearly along the guide bar and the rail/or rails by applying a force to the end of said structure remote from said guide bar, without the ladder or platform structure sticking or jamming.

It will also be seen that a technical problem resides in the provision of a structurally simple guide arrangement which will remain operable over a long period of time and which is able to co-act with the guide bar in a manner which will prevent the guide arrangement from disengaging from the guide bar, other than by partially or totally dismantling said guide arrangement.

Another technical problem resides in the provision of a guide arrangement for the aforesaid purposes which will solve the aforementioned problems and still enable the ladder structure or like structure to be moved along the guide bar in response to small applied forces.

Another technical problem is one of providing such a guide arrangement with guide members which are configured to enable said members to be readily mounted on or fitted to the guide bar and also to the ladder or platform structure.

SOLUTION Accordingly the present invention relates to a guide arrangement for facilitating linear movement of a frame construction, such as a ladder structure or a platform structure, or like structure, along preferably a single guide bar, the span of the frame construction being such as to necessitate supporting the construction on at least one rail extending parallel with the guide bar, through the intermediary of runners or support wheels.

It is proposed in accordance with the invention that two guide members are mounted in spaced apart relationship on the guide bar and are firmly connected to one another and to the frame construction, the frame construction in its longitudinal direction taking a pre-determined angular position (normally perpendicular) in relation to the longitudinal extension of the guide bar.

Each of the guide members has at least three lightlyjournalled rolling surfaces or runners which are so positioned around the guide bar as to ensure that said bar extends between the rolling surfaces and is held in running engagement with the frame construction.

According to one preferred embodiment, the guide bar has a part-circular cross-sectional shape and the rolling surfaces are spaced apart through a mutual angle of 1200.

Two of these rolling surfaces are preferably located in a transverse plane through the guide bar, whereas the third rolling surface is located outside this plane.

Each of the rolling surfaces may conveniently comprise the outer peripheral surface of a spherical or roller bearing.

It is also proposed in accordance with one variant of the invention that, for the purpose of constructing the guide arrangement, one guide member has a rod-shape part which, e.g. when the members are in their intended position on the guide bar, faces towards a similar rod-shaped part on the other guide member, and that these rod-shaped parts are firmly connected together by a hollow tubular connector, the inner-diameter of which is such as to leave a small clearance around respective rod-shaped parts.

The guide members and tubular connector are preferably made of a light metal, such as aluminium or an aluminium alloy.

An advantage is also afforded when one or more rails form a guide-bar construction on which a cylindrical support roller rests.

According to one embodiment of the invention the third rolling surface of one guide member faces away from the third rolling surface of the other guide member.

The guide bar and the guide arrangement, together with the two guide members, are preferably located adjacent one end part of the frame construction.

Finally, the guide bar will conveniently incorporate a T-shaped slot for accommodating the head of a bolt used to secure the guide bar to a support structure.

ADVANTAGES The advantages primarily characteristic of the inventive guide arrangement reside in the provision of means which will enable a relatively long ladder or platform structure, carried for linear movement along a guide bar and at least one -rail, to adopt a pre-determined angular position (perpendicular) to the longitudinal extension of the guide bar and to be moved along the guide bar and the rail in response to the application of a limited force to the part of the ladder structure distal from the guide bar, without mutual jamming of the guide bar and guide members.

The primary characteristic features of a guide arrangement constructed in accordance with the invention are set forth in the characterizing clause of the following claim 1.

BRIEF DESCRIPTION OF THE DRAWINGS An embodiment of the invention at present preferred and having features characteristic of the invention will now be described in more detail with reference to the accompanying drawings, in which Figure 1 is à perspective view of a readily dismantled and assembled frame construction forming a ladder which is mounted for linear movement along a horizontally extending guide bar and along a roof surface which is inclined to the horizontal; Figure 2 is a perspective view of one end part of one ofsev 'eral steps or like tread members forming part of the frame construction; Figure 3 is a sectioned end-view of a frame part or carriage member to which the post of a handrail is fitted; Figure 4 is a side view of the upper part of the handrail this upper part being raisable or lowerable through the agency of a pivotable arm system;; Figure 5 is an end-view illustration which shows the principles according to which the frame structure is moved linearly along a guide bar and a rail, and also illustrates a guide arrangement for guiding the linear movement of a frame construction along preferably a single guide bar and comprising a guide member according to a first embodiment; Figures 6 and 7 illustrate a second embodiment of a guide member; and Figure 7 also illustrates a method of joining together two light-metal component parts with the aid of a steel nail, one of said parts being configured to embrace the other of said parts over a limited area therealong.

DESCRIPTION OF PREFERRED EMBODIMENTS Figure 1 illustrates in perspective an easily dismantled and assembled frame construction 10, in the form of a ladder, positioned along a sloping roof 5 of a building 6.

The frame construction, or ladder, 10, is mounted for linear movement along a guide 7, which is described in more detail hereinafter with reference to Figures 5, 6 and 7, and has a span which enables it to rest on and be supported by one or more rails via runners on wheels 11, 11', a lowermost rail being referenced 8 in Figure 1. The remaining three rails are not referenced.

In the case of the Figure 1 embodiment, a further three such rails extend parallel with the guide 7.

The frame construction illustrated in Figure 1 can be considered to comprise of two mutually opposing frame parts 12, 13, which serve as carriage sidepieces. Extending in spaced relationship between the sidepieces 12, 13 are mutually identical steps, of which the lowermost step is referenced 14.

Figure 2 illustrates the part of the step 14 and the surface 14a of the step which are intended to face towards the sidepiece 12.

It will be seen from Figure 2 that one end part of the step is provided with at least one, preferably at least two or more holes 15, 15a, whereas the other end of the step has provided therein a horizontally extending slot 16, such that one and the same step can be used in different inclined positions, as described in more detail hereinafter.

Figure 3 is a sectional view of one of the two mutually opposing carriage sidepieces or frame parts, namely the sidepiece 1. The sidepieces have the form of a light metal profiled section, preferably an extruded aluminium profile, and each of the sidepieces presents on respective sides thereof two mutually facing, horizontally spaced attachment means, of which one is referenced 17 and the other 18, these attachment means being intended to co-act with floor sections or steps 14 extending between the frame parts or side pieces 12, 13.

If the mutually opposing frame parts 12, 13 should be positioned horizontally, the frame construction could therewith be used in a hanging position and it is obvious that the floor parts 14 need co-act solely with one 17 or the other 18 of the attachment means.

In the case of the illustrated embodiment, however, the frame parts are positioned obliquely to the horizontal, in which position the frame parts function as carriage sidepieces with the floor sections forming steps 14, and the two attachment means 17, 18 are intended to co-act with a respective end part of the step, i.e. with the slot 16 and one of the two holes 15, 15a.

It will be seen readily from Figure 2 that if a first bolt is brought into co-action with the attachment means 17 and the left-hand part of the slot 16 and a second bolt is brought into co-action with the attachment means 18 and with the hole 15, the carriage sidepieces 12 and 13 can be inclined slightly to the horizontal in the case of a horizontally positioned step, whereas if the attachment means 17 is caused to co-act with the right-hand part of the slot 16 and the attachment means 18 is caused to co-act with the hole 15a, the carriage sidepiece will adopt a much larger angle to the horizontal.It is thus obvious that the step 14 has been adapted for various angular positions of the carriage sidepieces, and it will also be obvious that further possibilities of changing the angle of the carriage sidepieces to the horizontal can be obtained by changing the distance between the attachment means provided on said end parts and therewith also the depth of the step.

It is also obvious that the transition from the right-hand side of the slot and the hole 15a to the left-hand part of the slot and the hole 15 is continuous.

It is therefore proposed in accordance with the invention that the steps are prefabricated in a number of different widths, e.g. at most two, between the carriage side pieces 12 and 13, e.g. three or four pre-determined depth dimensions, so as to be able to co-act with the attachment means in dependence on the angle at which the carriage sidepieces, or frame parts, slope.

Returning now to Figure 3, it will be seen that respective attachment means 17, 18 comprise a T-shaped slot which is dimensioned to hold the head of a bolt, said bolt being inserted through the slot 16 and fitted with a nut on the rear side 14a such as to hold the step 14 against the carriage sidepiece 12.

Each of the two mutually opposed frame parts or carriage sidepieces presents a respective attachment means 19, 20 which are spaced horizontally opposite one another and which are intended to cooperate with fastener means in the form of holes provided in posts 21 of a handrail or guardrail construction.

In the case of the embodiment illustrated in Figure 3, the post 21 is fitted to the carriage sidepiece 12, whereas in the case of the Figure 1 embodiment the posts are fitted to the carriage sidepiece 13.

The post 21 is fitted with the aid of a bolt 22 which coacts with the attachment means 20 and with the aid of a bolt 23 which co-acts with the attachment means 19.

The upper section 26 of the handrail or guardrail 25 is hinged at 28 to an elongated profile 29, through a pivotal arm system which includes an arm 27 which is also pivotally connected at 30 to the top part 31 of the rail 25, therewith enabling the upper section 26 to be swung up and down.

Figures 5, 6 and 7 illustrate a guide arrangement for a frame construction 10, such as a ladder, a platform or the like arranged for linear movement along preferably a single guide 7, the frame construction having a span such that it rests against and is supported by at least one rail 8 extending parallel with the guide 7, via runners or wheels 11, 11'.

The guide arrangement of the illustrated embodiment includes two guide members 35, 35' which are positioned at a distance along the guide 7 and which are interconnected by a tubular connector 1, which in turn is connected to the frame construction 10, such that the frame construction takes a pre-determined angular position (perpendicular) relative to the longitudinal extension of the guide 7.

Each of the guide members has journal led thereon three rolling or runner surfaces 36, 37 and 38 which co-act with the guide 7 for smooth movement thereon and which are so oriented as to enable the guide to pass between the rolling surfaces or runners and hold the frame construction 10 in running engagement with the guide 7.

The guide 7 illustrated ir-Figure 5 has a part circular cross-section, so as to enable the rolling surfaces 36, 37 and 38 to be positioned apart at an angular distance therebetween of 1200.

Two of these rolling surfaces are located in a transverse guide plane "A", whereas the third rolling surface is located outside said plane.

According to the present invention, each of the rolling surfaces or runners 36, 37 and 38 is formed by the outer peripheral surface of a ball bearing.

In accordance with the invention, and as illustrated in particular in Figures 6 and 7, the guide members are each provided with a rod-like part 2. These rod-like parts 2 extend towards each other from respective spaced-apart guide members 35, 35-' and are interconnected by the aforesaid tubular connector 1, the internal diameter of which is such as to leave a small clearance around respective rod-like parts 2. The guide members and tubular connector may be made of a light metal, such as aluminium.

It will be seen that the rail 8 also comprises a guide construction or assembly, against which a cylindrical support roller or wheel 11 rests.

The invention requires the use of only one guide which carries two mutually spaced guide members.

Figure 7 shows that the third rolling surface 38, i.e. the upper rolling surface of the one guide member 35, faces away from the third rolling surface of the other guide member.

Furthermore, Figure 1 shows that the guide 7 and two guide members 35 and 35' are arranged adjacent one end part, i.e. the upper end part, of the frame construction 10.

It will be seen from Figure 5, furthermore, that the guide 7 is provided with a T-shaped slot which accommodates the head of a bolt used to fasten the guide to a supporting surface or foundation surface 40.

Figure 5 also shows that the inventive principles apply when the guide 7 and the rail 8 extend in the horizontal plane.

Figure 6 shows that the rolling surface 37 is attached to a projection 41 by means of a bolt 42 and a nut 43.

Figure 7 also illustrates a method of fastening an aluminium tubular connector 1 to an aluminium rod-like part 2 of a guide member.

The present invention thus also provides a method of joining together two light-metal parts, preferably extruded light-metal profiles, sbch as aluminium sections.

In accordance with the invention, the one part, i.e. the tubular-connector 1 is arranged and configured such as to be able to embrace the second part 2 over a limited area 2a.

To this end, the tubular connector 1 is provided with a hole 1' , and the connector is moved over the area 2a so that the second part 2, i.e the rod-like part, is located immediately adjacent the inner surface la of the hole 1' or vice versa.

The light-metal parts 1 and 2 are joined together by means of a device '3 which co-acts lockingly with said parts within said area.

In the case of the Figure 7 illustration, the second part 2, or rod-like part, is conceived to be inserted into the first part, or tubular connector 1, in the aforedescribed manner.

The securing or locking device 3 of the illustrated em bodiment has the form of a steel nail or like fastener, which is applied with the aid of a known nail gun (not shown), the loading and dimensions of the steel nail being selected in each case such that the steel nail will pass through the mutuall facing surfaces la, 2a of the two parts.

The size of the charge and the dimension of the steel nail are in each case selected so that the steel nail 3 will pass completely through the edge part of the one part 1 and half way through the other part 2. This will ensure that the nail, or like fastener, will penetrate the mutually facing surfaces la and 2a so that the centre part of the nail is located adjacent said surfaces.

The embodiment in which the one part 1 is a hollow tube and the other part 2 is rod-shaped is particularly significant of the invention. In the case of this embodiment it is proposed, in accordance with the invention, that the maximum charge possible is selected with regard to the nail gun and that the steel nail has a length of 25 mm and a diameter of 5.6 mm, such that the nail will pass completely through the wall lb of the hollow tubular first part 1 and half way through the rod-shaped second part 2, with the point 3a of the nail located at the centre of said second part. The steel nail shall be driven diametrically, as illustrated in Figure 7.

In order to provide a still more secure join between the two light-metal parts 1 and 2, it is proposed that two or at most three nails are driven, side-by-side and in one and the same direction, into the first and second parts in the region where the surfaces la and 2a face each other.

Alternatively, two or more nails may be applied adjacent one another within. said area and in mutually opposite directions.

In accordance with one variant of the invention, the wall lb of the one part 1 shall have within said area or region a thickness which corresponds to 10-30 % of the outer diameter of said first part. This wall thickness is preferably from 15-25 % of the outer diameter of said part.

The diameter of the other part 2, e.g. the rod-shaped part, will have a diameter of from 10-40 mm, preferably from 2030 mm.

Furthermore, the hole 1' in the one part 1 shall have a diameter which is at most 2.0 mm, preferably 1.0-0.2 mm, larger than the diameter of the other part 2.

In a particular application of the present invention, three steel nails having a length of 25 mm were applied side-by-side in the longitudinal extension of said part, in the manner illustrated in Figure 7. The one part 1 had an outer diameter of 43 mm and an inner diameter of about 28 mm. The other part 2 had a slightly smaller diameter than the inner diameter of the one part 1, such as to leave a clearance of 0.4 mm. When the two parts were joined together in the aforedescribed manner, the stength of the joint prevailed over the tensile strength of the other part 2. The use of more than three nails is unnecessary for obtaining the requisite strength against tensile forces.

It will be understood that the invention is not restricted to the illustrated and described embodiments thereof and that modifications can be made within the scope of the following claims.

Claims

1. A guide arrangement for a frame construction, such as a ladder structure, a platform or the like, which is mounted for movement along preferably solely one guide bar and which has a span such that the frame construction will rest against and be supported by at least one rail extending parallel with the guide bar, through the intermediary of runners or rollers, characterized in that two guide members are located in mutually spaced relationship along the guide bar and are firmly joined together and to said frame construction, such that the frame construction takes a pre-determined angular position in relation to the longitudinal extension of the guide bar; in that each guide member has journalled thereon three rolling surfaces intended for co-action with said guide bar; and in that the rolling surfaces are positioned so that the guide bar extends between said surfaces to hold the frame construction in rolling or running engagement with the guide bar.

2. An arrangement according to claim 1, characterized in that the guide bar has a part-circular cross-sectional shape; and in that the rolling surfaces are mutually spaced apart at an angle of 1200.

3. An arrangement according to claim 1 or claim 2, characterized in that two rolling surfaces are arranged in a transverse plane through the guide bar and that the third rolling surface is arranged outside said plane.

4. An arrangement according to claim 1, 2 or 3, characterized in that each of the rolling surfaces comprises the outer peripheral surface of a ball bearing.

5. An arrangement according to any of the preceding claims, characterized in that one guide member has a rodshaped part which faces towards a similar rod-shaped part on the other guide member; and in that said rod-shaped parts are joined together by means of a tubular connector whose inner diameter is adapted to leave a small clearance around respective rod-shaped parts.

6. An arrangement according to claim 5, characterized in that the respective guide members and the tubular connector are made of a light metal, such as aluminium or an aluminium alloy.

7. An arrangement according to any of the preceding claims, characterized in that the rail comprises a guide structure against which a cylindrical support runner rests.

8. An arrangement according to claim 3, characterized in that the third rolling surface of one guide member is intended to face away from the third rolling surface of the other guide member.

9. An arrangement according to any of the preceding claims, characterized in that a guide bar and two guide members are located adjacent one end part of the frame construction.

10. An arrangement according to any of the preceding claims, characterized in that the guide bar has provided therein a T-shaped slot which is intended to accommodate the head of a bolt for securing the guide bar to a support structure.

11. A guide arrangement constructed and adapted for use substantially as hereinbefore described with reference to and as shown on the accompanying drawings.