DE2443649A1 - Fully adjustable spring drive means for blackboards - comprises combination of swash-plate and leverage system allowing precise lift - Google Patents

Abstract

The spring drive for blackboards or wall charts comprises a combined swash-plate leverage system wherein one or more springs are suspended in the lever arm so that any desired height and lift can be achieved. The spring characteristic is compensated by a swash-plate on each side with one or more windings. The two spring balances are mounted in the middle of the lifting frame and are restricted in their movement up and down by stops. The drive means can be mounted adapted for adjustment on a full-length shaft of the spring drive, wherein the drive wheels and swash-plates are made of cast aluminium. If a welded construction is preferred then the cable groove can be formed by an angle iron bent over the corner.

Description

Description Spring drive for school blackboards or similar facilities are known.

Due to a lack of supplementary options and insufficient @ ach = adjustment options, wa These drives have not yet been fully balanced. Above all, however, was the table lift not sufficient to deal with complex, i.e. expensive facilities such too receive.

The subject of the invention is now a spring drive which any Gewü @ se te lifting height can be reached and its spring drive j @ are currently being readjusted can. this especially when slide rule in large demonstration execution etc. the same are attached.

The previous school blackboards in wood @ etall are also unsuitable Execution, since enormous weights have required unnecessary spring expenditure up to now and counterweight expenditure ) For this reason, panels made of Dural sheet metal are pressed at the same time - similar to the facades -Elements made of aluminum sheet suggested. Due to the beveled or deep-drawn edge the required rigidity is achieved with these sheet metal plates.

By installing Fagnetfe @@@ rn or dü @@ en iron sheets can be attached to this Blackboard can then also be worked with magnets.

Slide rules can be held, see above, or in the same way the drawing triangles are fixed in each position.

The spring drive is doubly designed for larger panels so that an even load on the engine is achieved, and vice versa an even drive @ b.

The common shaft 1 carries the winding wheels fitted on both sides with single or multi-turn spiral tires, depending on the extended lifting height.

This device can be tightened evenly by means of an adjusting nut both sides of the panel can be adjusted.

The spring characteristic is also determined by a cam on each side balanced with one or more turns.

The two springs are preferably in the middle of the lifting frame 2 mounted, axle pin 10. Appropriately, the deflections of the spring rocker limited by stops at the top and bottom.

The spring support 3 on the other side is preferably each outside in the frame stored so that in the middle for both systems together with a tension spindle the The basic tensile force of the springs can be adjusted.

Handwheel or adjustment device 8. This fine adjustment can be faster = development can also be accomplished with a lockable lever system.

The lifting height or the spring expansion can be determined by the curve diagram shown ben-lever arm combination can be optimally designed.

Claims (3)

Claims ----------------- 1) combined crank disc-lever arm-spring drives d.g.d. one or more springs are attached to the Eebelarm @, so that the @ @translation cam disc diameter to drive wheel = diameter 5 in your combination of o @ timalen @andtafelhub results, in cooperation with the spring lever 2. 2) Using a @eichte @ andtafel @ onstr @@ tion, if possible from a dura @ deep-drawn plate, this construction is limited to as little spring effort as possible , or plastic plate in @abenbauart. 3) Spring swing arm for @ r link @. right-hand drive in 10 bearings and limited by stops 11 -depending on Tafe @ höne in the swing out, which at the same time @@@ uch a berdre @@ n prevents 4) The mutual suspension is also in cantilever 3. it results that i. the system center both systems with a spindle or can be retensioned with a lever system a locking gate is required. 5) kombini @ rt @ r cam disc lever arm @ spring drive , d.g.d. a continuous shaft slid on the al @ e drive so that it can be adjusted can be. The drive rotors or camshafts are d @ with preferably @ off Cast aluminum. If a welded construction is preferred, the rope groove becomes formed by 1 angle iron that is bent over the Leke (pipe bending device = device).