Adjustment- and arresting mechanism especially for a drafting table

Claim 2

An adjustment and arresting mechanism, for a load, particularly for a drafting table, wherein adjustments are to be carried out substantially along a straight line and/or about at least one axis, comprising an adjustment and arresting cylinder provided for elevational adjustment of the load and an adjustment and arresting cylinder for inclined adjustment of the load, each of said cylinders possessing a predetermined swept volume filled with a fluid medium, a piston arrangement including a piston rod and a double-acting piston member within said cylinder for subdividing said volume into two partial chambers, means defining a communication channel between both said partial chambers to permit the flow of the fluid medium therebetween, shut-off valve means for said communication channel, two members which are to be moved relative to one another associated with each of said cylinders, means for operatively connecting respective ones of said cylinders with one of said members, means for operatively connecting the piston rod associated with a respective cylinder with the other of said members, actuating means for said shut-off valve means, said actuating means incorporating a Bowden cable for each shut-off valve means of the respective cylinders, a common manually operable element for engagement by the Bowden cables of both of the adjustment and arresting cylinders, and means defining a number of tracks along which there can be moved said manually operable element, said track defining means providing three track sections forming a substantially U-shaped track arrangement, a neutral position of said manually operable element corresponding to a closed condition of said shut-off valve means for said cylinders being located at a point of intersection of two of said track sections, whereas movement of said manually operable element along said track sections exerts a traction force upon the one, the other, or all of said Bowden cables and thus opens the associated shut-off valve means.

Claim 3

An adjustment and arresting mechanism for a table comprising: a relatively fixed part, a relatively movable part, first adjustment means for adjusting said table along a substantially straight line, said first adjustment means including a first cylinder with a first piston slidably disposed therein to form a fluid spring with pressurized fluid in said cylinder which is communicable with opposite sides of said first piston by way of a first valve means such that said first piston and first cylinder are freely movable with respect to one another when said first valve means is open and such that said first piston and first cylinder are locked relatively immovably with respect to one another by said pressurized fluid when said first valve means is closed, one of said first cylinder and first piston being connected to said fixed part and the other of said first cylinder and first piston being connected to said movable part such that relative movement of said first cylinder and first piston is accompanied by corresponding relative linear adjusting movement of said fixed and movable parts, second adjusting means for pivotally adjusting said table about at least one axis, said second adjustment means including a second cylinder with a second piSton slidably disposed therein to form a fluid spring with pressurized fluid in said cylinder which is communicable with opposite sides of said second piston by way of second valve means such that said second piston and second cylinder are freely movable with respect to one another when said second valve means is open and such that said second piston and second cylinder are locked relatively immovably with respect to one another by said pressurized fluid when said second valve means is closed, one of said second cylinder and second piston being connected to said movable part and the other of said second cylinder and second piston being connected to said table such that relative movement of said second cylinder and second piston is accompanied by corresponding relative pivotal adjusting movement of said table with respect to said movable part, and manually operable valve control means for selectively moving said first and second valve means between open and closed positions, wherein said valve control means includes a single manually operable element operatively connected to both said first and second valve means such that selective opening of either or both of said first and second valve means can be effected by movement of said single element, and wherein said valve control means includes a guide track for guiding movement of said single element between a plurality of positions corresponding respectively to: opening of said first valve means with said second valve means closed, opening of said second valve means with said first valve means closed, both valve means closed, and both valve means open.

Claim 4

An adjustment and arresting mechanism for a table comprising: a relatively fixed part, a relatively movable part, first adjustment means for adjusting said table along a substantially straight line, said first adjustment means including a first cylinder with a first piston slidably disposed therein to form a fluid spring with pressurized fluid in said cylinder which is communicable with opposite sides of said first piston by way of a first valve means such that said first piston and first cylinder are freely movable with respect to one another when said first valve means is open and such that said first piston and first cylinder are locked relatively immovably with respect to one another by said pressurized fluid when said first valve means is closed, one of said first cylinder and first piston being connected to said fixed part and the other of said first cylinder and first piston being connected to said movable part such that relative movement of said first cylinder and first piston is accompanied by corresponding relative linear adjusting movement of said fixed and movable parts, second adjusting means for pivotally adjusting said table about at least one axis, said second adjustment means including a second cylinder with a second piSton slidably disposed therein to form a fluid spring with pressurized fluid in said cylinder which is communicable with opposite sides of said second piston by way of second valve means such that said second piston and second cylinder are freely movable with respect to one another when said second valve means is open and such that said second piston and second cylinder are locked relatively immovably with respect to one another by said pressurized fluid when said second valve means is closed, one of said second cylinder and second piston being connected to said movable part and the other of said second cylinder and second piston being connected to said table such that relative movement of said second cylinder and second piston is accompanied by corresponding relative pivotal adjusting movement of said table with respect to said movable part, and manually operable valve control means for selectively moving said first and second valve means between open and closed positions, wherein said valve control means includes a single manually operable element operatively connected to both said first and second valve means such that selective opening of either or both of said first and second valve means can be effected by movement of said single element, and wherein said valve control means includes a guide track for guiding movement of said single element between a plurality of positions corresponding respectively to: opening of said first valve means with said second valve means closed, opening of said second valve means with said first valve means closed, both valve means closed, and both valve means open.

Claim 5

A mechanism according to claim 2, wherein said valve control means includes means for normally holding said single element in a neutral position with both of said valve means closed.

Claim 6

A mechanism according to claim 2, wherein said valve control means includes a first Bowden cable leading from said single element to a member controlling said first valve means, and a second Bowden cable leading from said single element to a member controlling said second valve means.

Claim 7

A mechanism according to claim 2, wherein said track includes three track sections forming a substantially U-shaped track arrangement, a neutral position of said single element corresponding to the closed condition of both valve means being located at the point of intersection of two of said track sections.

Claim 8

A mechanism according to claim 2, wherein said first cylinder is fixed to said fixed part and said second cylinder is fixed to said displaceable part.

Claim 9

A mechanism according to claim 2, wherein said table is a drafting table.

Claim 10

A mechanism according to claim 2, wherein each of said fluid springs is a gas spring which is constructed as a closed unit with a constant total supply of compressed gas above atmospheric pressure in the respective cylinders for all adjustment positions of said table and with said valve means only serving to transfer portions of said compressed gas between cylinder chambers at opposite sides of the respective cylinders.

Claim 11

A mechanism according to claim 2, wherein said guide track includes locking detent means for maintaining said single element in each of said plurality of positions.

Claim 12

A mechanism according to claim 9, wherein said valve control means includes means for automatically returning said single element to a neutral position with both of said valve means closed whenever said single element is out of engagement with said locking detent means.

Claim 13

A mechanism according to claim 10, wherein said first and second cylinders are arranged alongside one another and are spaced from one another in a direction transverse to said lengthwise axis.

Claim 14

A mechanism according to claim 9, wherein said valve control means includes a first Bowden cable leading from said single element to a member controlling said first valve means, and a second Bowden cable leading from said single element to a member controlling said second valve means.

Claim 15

A mechanism according to claim 12, wherein said valve control means includes means for automatically returning said single element to a neutral position with both of said valve means closed whenever said single element is out of engagement with said locking detent means.

Claim 16

A mechanism according to claim 2, wherein said fixed and movable parts are constructed as telescoping parts with said movable parts being movable along a lengthwise axis, and wherein said first piston and first cylinder as well as said second piston and second cylinder are movable respectively with respect to one another along axes parallel to said lengthwise axis, said second piston being pivotally connected to said table.

Claim 17

A mechanism according to claim 14, wherein said first and second cylinders are arranged alongside one another and are spaced from one another in a direction transverse to said lengthwise axis.

Claim 18

A mechanism according to claim 14, wherein said first cylinder is fixed to said fixed part and said second cylinder is fixed to said displaceable part.

Claim 19

A mechanism according to claim 14, wherein said valve control means includes a first Bowden cable leading from said single element to a member controlling said first valve means, and a second Bowden cable leading from said single element to a member controlling said second valve means.