FI89127B - Reading stand with articulated bar - Google Patents

Abstract

The invention concerns a reading support which is provided with an articulated mechanism affording a large number of possible settings by means of applying a small external force, and in which the adjusted position can be locked automatically by slight elastic deflection of the articulation when a relatively heavy book is placed on the support. The hinge is released by turning the console 2 in the direction of arrow A. <IMAGE>

Description

1 89127

ARTICULATED READING STAND

The invention relates to a reading stand with an articulated cantilever boom, in which a book to be read is placed so that it does not have to be carried by hand during reading, and whose position can be easily adjusted and the required tension is self-adjusting and easy to loosen.

10 Articulated booms are now commonly used as brackets for table lamps. The luminaires are characterized by the fact that the weight of the structure does not change during use, in which case, for example, the use of auxiliary springs makes sense. In addition, the luminaire is relatively light, so the structure of the boom does not have to be particularly strong.

15 The load on the reading stand can vary greatly. E.g.

a small novel weighs only a few hundred grams, while some textbook may weigh up to a kilogram or two. When such a book is placed, for example, at the end of a 0.6 m long articulated projection, the torque on the joint becomes so great that the current projections of the lamps 20 do not hold their position firmly.

In a conventional folding joint between two projections, in which each projection rotates about the same axis and; where the grip is based on pressing the projections in the axial direction • .to each other, the pressing is effected by a 25-nut rotatable on the shaft (e.g. the feet of the migraphones). In order to obtain a sufficient torque for such a flange joint, a really high pressure must be applied to it in the rack application in order to hold the joint.

In addition, the problem is that the adhesion friction is generally higher than the sliding friction. In this case, when the rack is set to the 30th to the appropriate position and a book is placed with the rack just and 2 89127 just held up, the tightening torque becomes critical. And then when the stand is swung a little, for example when turning the page, the joint starts to slip and the book falls.

The object of the invention is to provide a smooth joint which can be locked tightly with a small external force, which, moreover, automatically tightens itself as the load increases, and which can again be opened again with a small external force.

The invention will now be described in more detail by means of a preferred embodiment shown in the accompanying drawing, in which Figure 1 shows the articulation mechanism according to the invention in its typical operating position and Figure 2 is a section according to arrows II-II in Figure 1. Attached to the stems 1 and 2 shown in Fig. 1 are almost one-size-fitting annular sleeves 4 and 5 shown in Fig. 2 so that the stems can be articulated parallel to the same shaft 6. Fig. 2 shows how when the shaft 6 is mounted, it passes freely through the sleeve 5 and joins thus with a thread inside the sleeve 4. The shaft 6 expands at an angle α inside the sleeve 5 and the sleeve 5 is turned to a corresponding shape.

20 When the shaft 6 is rotated in the arrow A direction, tightens the sleeve between 4 and 6 5 parts and the recesses go to 0, touching cones parts 5 and 6a each other and selecting carboxylic angle amounts sufficiently small, it means substantially smaller than the thread 8 of the flank angle, preferably less than 45 degrees, 25 · .: friction between parts 5 and 6 is greater than between fractions 4 and 6.

• If the ort 2 is now rotated in direction A, either by hand or due to the weight of the book 10, the sleeve 5 attached to the ort 2 rotates along the shaft 6, which in turn rotates deeper into the thread of the sleeve 4,. so the joint locks completely.

3Q-- The next time you want to adjust the joint, the shaft 3 39127 6 may have been tightened so tight that it cannot be loosened by turning it from its own roughened handle 6b, in which case the ribs 1 and 2 also act as lever arms in the opening as long as between parts 4, 5 and 6. does not have gaps, a book 10 5-shi lift getting joint can be opened by rotating a small external force from a bridge two arrow A direction. In order for the parts 5 and 6 to also be released from each other when opened, the cone angle α must be more than 5-10 degrees, depending on the materials.

By increasing the torque arm of the locking torque, the need for locking force can be reduced. This can be applied well by making the shaft 6 a tube with a large diameter (about 50 mm) and a small wall thickness (about 3-5 mm), whereby the joint becomes structurally light and relatively little compressive force is required and the shaft extension 6b acts as a roughened handle 15 for the shaft. .

To prevent the linkage from being misused, the joint is equipped with override limiters 9.

Claims (2)

4 89127 A reading stand with an adjustable joint, characterized in that the two successive cantilever elements 1 and 2, or 1 and 8 of the boom are axially rotated concentrically on the shaft 6, so that when the shaft 6 is free the projections can rotate freely relative to each other and the joint is pre-tensioned by rotating the shaft A direction to tighten the set kirjatelineelle additional weight 10 circulates joints to provide the required torque and rotating the rail to the two arrow A direction against the joint will open again. Reading stand 15 according to claim 1, characterized in that the shaft 6 is a thin-walled tube, the extension 6b of which forms a handle for pre-tightening the joint. li 5 89127 5. The operation of the console with the control panel, which means that the following console elements of the console element 1 and 2, or 1 and 8 of the axle 6 are also present in the center of the console, In this case, the axles of the axles with the pylons are airtight A, 10 spans of the axles 10 of the axle head of the pendulum are a second moment, a moment and a moment of 2 is used in the case of a silent ether. 2 Läsställning 1 enligt patentgrav är känd av det att Axel 6 är rör med tunnvägg ,ars förlängning 6 b bildar handtag 15 för spänspänna leden.