US3877543A

US3877543A - Scaffolding for building

Info

Publication number: US3877543A
Application number: US472304A
Authority: US
Inventors: Tadashi Iwata
Original assignee: Individual
Current assignee: Individual
Priority date: 1974-05-22
Filing date: 1974-05-22
Publication date: 1975-04-15
Anticipated expiration: 1992-04-15

Abstract

A scaffolding for building is described, in which there is provided a horizontal platform that is mounted to a plurality of vertical posts so as to be freely moved up and down along said vertical posts while pinching each of said posts with rollers and drive rollers pivotably mounted on an arm lever provided on said platform, worm gear means is coupled to said drive rollers to move the horizontal platform up and down by rotating the drive rollers, and when a downward load is applied to said platform said rollers and said drive rollers are automatically pressed against the post, so that the platform may be prevented from slipping down by the frictional force generated therebetween.

Description

Iwata SCAFFOLDING FOR BUILDING 51 Apr. 15, 1975 3,727,723 4/1973 Pitcairn 182/133 Primary Examiner-Reinaldo P. Machado [57] ABSTRACT A scaffolding for building is described, in which there is provided a horizontal platform that is mounted to a plurality of vertical posts so as to be freely moved up and down along said vertical posts while pinching each of said posts with rollers and drive rollers pivotably mounted on. an arm lever provided on said platform, worm gear means is coupled to said drive rollers to move the horizontal platform up and down by rotating the drive rollers, and when a downward load is applied to said platform said rollers and said drive rollers are automatically pressed against the post, so that the platform may be prevented from slipping down by the frictional force generated therebetween.

6 Claims, 4 Drawing Figures [76] Inventor: Tadashi I'wata, 2472 Oaza Kanokami Kano-cho, Yamaguchi-ken, Japan [22] Filed: May 22, 1974 [21] Appl. No.: 472,304

[52] US. Cl 182/133; 182/148 [51] Int. Cl A63b 27/00 [58] Field of Search 182/145, 146, 148, 141, 182/133, 187; 248/221, 235, 243

[56] References Cited UNITED STATES PATENTS 3,016,989 l/1962 Lindmark 182/148 3,148,857 9/1964 Hutchinson 3,237,720 3/1966 Landquist 3,520,383 7/1970 Loock 182/133 C? V 7 5 1a 1412 -j .L i. 6 9 N 10 15 6 7 111 Ill 5 1 11 13 a? V 7 1412 J a 8 18 PATENTEUAPRI SIBYS 3.877. 543

sum 1 o a h PFATENTEDAPR I 5l975 sum 2 BF 3 FIG.2

PATENTEUAPR 1 5197s sumsuf FIGA SCAFFOLDING FOR BUILDING art scaffolding has a shortcoming in that it takes a long time for the work of assembling and dismembering the scaffolding.

In addition, the work of assembling a scaffolding, es-

pecially a scaffolding for a tall building or the like, is.

very dangerous.

Also it necessiate a great labor for a worker to go up and down on the assembled scaffolding.

Therefore, it is an object of the present invention to provide a scaffolding for building which can be assembled or dismembered in a shorter time than the aforementioned conventional scaffoldings.

Another object of the present invention is to mitigate the labor of a worker upon going up and down on an assembled scaffolding for building.

Still another object of the present invention is to provide a scaffolding in which provision is made such that a platform on which a worker rides may not inadvertently slip down.

One feature of the present invention for achieving the aforementioned objects is to provide a scaffolding for building including a plurality of posts disposed in the vertical direction and a horizontal platform mounted to said posts so as to be freely moved up and down along the posts, in which a base end of an arm lever is connected to said platform, the other end thereof is extended across the posts, said extended arm lever portion being inclined upwardly at an angle, rollers are pivotably mounted at the extremity of said the other end of the arm lever, drive rollers are pivotably mounted on the arm lever so as to pinch each of said posts with said rollers and said drive rollers, worm gears are provided on the respective shafts of said drive rollers, and said worm gears are meshed with worms which are in turn coupled to a prime motor.

These and other objects and features of the present invention will be more fully understood from the following description taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a side view of a scaffolding for building according to the present invention,

FIG. 2 is a plan view of the same,

FIG. 3 is an enlarged partial cross-section view taken along line IIIIII in FIG. 2, and

FIG. 4 is an enlarged partial cross-section view taken along line IVIV in FIG. 2.

Referring now to the drawings, reference numeral 1 designates a plurality of posts disposed in the vertical direction, to which is mounted a horizontal platform 2 so as to be freely moved up and down along said posts I. The platform 2 is assembled of a frame 3 and a plurality of lattice rods 4 as shown in FIG. 2, and a worker or workers ride on the platform 2 to perform necessary works.

To the platform 2 are fixedly secured a plurality of arm levers 5 at their substantially half portions, and the other half portions extend towards the posts 1. At the extremities of the extensions are pivotably mounted rocking levers 6 at their center with a pin 7, and at the upper and lower end of the rocking levers 6 are pivotably mounted rollers 8 with shafts 9 so as to be freely rotated. Around the outer circumference of the roller 8 is formed a rubber layer 10.

Drive side rocking levers 11 are pivotably mounted to the arm levers 5 with a pin 11 at a position somewhat separated from said extremities towards the platform 2, four drive rollers 13 are pivotably mounted to the rocking levers 11 with shafts l4, and a rubber layer 15 is formed around the outer circumference of the drive roller 13.

These drive rollers 13 and the aforementioned rollers 8 pinch the post 1 on its opposite sides.

In the arm lever 5, the straight line connecting the pin 12 and the pin 7 is inclined upwardly with respect to a horizontal line H-H passing through the pin 12 at an angle of 0. This inclination could be eitheroriginally given in design or caused by the dead load of the platform 2 or a load W thereon when a gravity is exerted upon the scaffolding.

When a concentrated load W is applied to a point on the platform apart from the pin 12 by a distance L, we have the following relation of equilibrium:

W(L lcos 0) Plsin 0 .where 1 represents the distance from the pin 12 to the pin 7, and P represents a horizontal reaction force P exerted upon the pin 12. Then, between the post 1 and the drive rollers 13 is generated a large and stable frictional force F equal to or less than the maximum frictional force that is determined by the reaction force P and the coefficient of static friction between the post I. and the drive rollers 13, and the load W is counterbalanced by said frictional force F. When the load W does not exist, the dead load of the platform 2 itself results in a reaction force corresponding to the dead load at the same position as the reaction force P. Accordingly, the post 1 has the rollers 8 and the drive rollers 13 pressed thereagainst continuously on its opposite sides. In order to increase the frictional force between the contact surfaces of the drive roller 13 and the post 1, the rubber layer 15 is formed on the outer circumference of the drive roller 13 and a serrated surface 17 is formed on the surface of the post 1. On the shaft 14 of the drive roller 13 is fixedly secured a worm wheel 18, which is in turn meshed with a worm 19, a V-pulley 21 is fixedly supported at one end of a shaft 20 outside of a support 16, and a V-belt 23 is wound and stretched around the V-pulley 21 and a prime motor 22.

When a worker rides on the platform 2 and actuates the prime motor 22, the worms 1? are rotationally driven to rotate the worm wheels 18 meshed therewith, and further the drive rollers 13 are rotated, so that the platform 2 may be freely moved up and down along the side surface of the post 1.

When the platform 2 has reached a predetermined height and the rotation of the prime motor 22 is stopped, the load W applied to the platform 2 results in a torque for rotating the drive roller 13. However, since the worm wheel 18 that is meshed with the worm 19 is fixedly mounted on the shaft 14 of the drive roller 13, the drive rollers 13 cannot be rotated. Also, since a large stable frictional force F is exerted between the circumferential surface of the drive roller 13 and the side surface of the post 1, the drive rollers l3 are inhibited to slip down along the side surface of the post 1 without being rotated. As a result, the platform 2 is kept stationary at the stopped position.

While the present invention has been described above in connection to its specific embodiment. it is intended that the scope of the invention should not be limited to the embodiment described above and illustrated in the accompanying drawings but many changes and modifications could be made without departing from the spirit of the invention.

What is claimed is:

l. A scaffolding for building including a plurality of posts disposed in the vertical direction and a horizontal platform mounted to said posts so as to be freely moved up and down along the posts, characterized in that said scaffolding comprises:

A. arm levers having their one end portions coupled to said platform and the other end portions extended towards said posts, said extended portions being inclined upwardly with respect to the horizontal direction at an angle;

B. rollers pivotably mounted at the extremities of said extended portions of said arm levers;

C. drive rollers disposed on the opposite sides of the posts to said rollers and pivotably mounted on said arm levers;

D. worm wheels provided on the same shafts as said drive rollers; and

E. worms coupled to a prime motor on one hand and meshed with said wonn wheels on the other hand.

2. A scaffolding for building as claimed in claim 1, characterized in that said rollers are pivotably mounted in multiple on a rocking lever, and said rocking lever is pivotably mounted at the extremity of said arm lever.

3. A scaffolding for building as claimed in claim 1, characterized in that said drive rollers are pivotably mounted in multiple on a rocking lever, and said rocking lever is pivotably mounted at the base of said extended portions of said arm levers.

4. A scaffolding for building as claimed in claim 1, characterized in that rubber layers are formed on the outer circumferences of said rollers and said drive rollers.

5. A scaffolding for building as claimed in claim 1, characterized in that a V-pulley is fixedly mounted on the shaft on which said worms are fixedly secured, and a V-belt is wound and stretched around said V-pulley and said prime motor.

6. A scaffolding for building as claimed in claim 1, characterized in that a serrated surface is formed on the face of said post to be contacted with said drive rollers.

Claims

1. A scaffolding for building including a plurality of posts disposed in the vertical direction and a horizontal platform mounted to said posts so as to be freely moved up and down along the posts, characterized in that said scaffolding comprises: A. arm levers having their one end portions coupled to said platform and the other end portions extended towards said posts, said extended portions being inclined upwardly with respect to the horizontal direction at an angle; B. rollers pivotably mounted at the extremities of said extended portions of said arm levers; C. drive rollers disposed on the opposite sides of the posts to said rollers and pivotably mounted on said arm levers; D. worm wheels provided on the same shafts as said drive rollers; and E. worms coupled to a prime motor on one hand and meshed with said worm wheels on the other hand.