Precision square

Claim 2

A precision square comprising a measuring surface adapted to receive a measuring instrument, surface-engaging means in fixedly disposed relation to said measuring surface accurately defining a plane substantially perpendicular to said measuring surface, said surface-engaging means being adapted to accurately engage a nominally vertical surface at a plurality of spaced-apart locations, and suspending means for engaging a hanger adjacent the nominally vertical surface so as to hang said square in a position in which said surface-engaging means accurately engages the nominally vertical surface and in which the measuring surface is horizontal.

Claim 3

A precision square comprising a measuring surface adapted to receive a measuring instrument, surface-engaging means in fixedly disposed relation to said measuring surface accurately defining a plane substantially perpendicular to said measuring surface, said surface-engaging means being adapted to accurately engage a nominally vertical surface at a plurality of spaced-apart locations, and suspending means for engaging a hanger adjacent the nominally vertical surface so as to hang said square in a position in which said surface-engaging means accurately engages the nominally vertical surface and in which the measuring surface is horizontal.

Claim 4

A precision square comprising a measuring surface adapted to receive a measuring instrument, surface-engaging means in fixedly disposed relation to said measuring surface accurately defining a plane substantially perpendicular to said measuring surface, said surface-engaging means being adapted to accurately engage a nominally vertical surface at a plurality of spaced-apart locations, and suspending means for engaging a hanger adjacent the nominally vertical surface so as to hang said square in a position in which said surface-engaging means accurately engages the nominally vertical surface and in which the measuring surface is horizontal.

Claim 5

The precision square of claim 1 in which said suspending means comprises first suspending means for hanging said square in a first orientation and second suspending means for hanging said square in a second orientation, said second orientation being displaced from said first orientation by 180*.

Claim 6

The precision square of claim 2 wherein said first and second suspending means are arranged so that the same plurality of locations on said nominally vertical surface is engaged when said square occupies its first and second orientations.

Claim 7

The precision square of claim 3 in which said surface-engaging means comprises four buttons.

Claim 8

The precision square of claim 3 on which at least two parallel measuring surfaces are provided.

Claim 9

The precision square of claim 5 in which said surface-engaging means comprises an even number of at least four symmetrically arranged buttons.

Claim 10

The precision square of claim 6 in which said buttons have ground and lapped flat surfaces.

Claim 11

The precision square of claim 7 in which the flat surfaces of said buttons are surrounded by sharp edges.

Claim 12

The precision square of claim 5 in which said two measuring surfaces are disposed on opposite sides of a measuring block.

Claim 13

The precision square of claim 9 further comprising two parallel side members connected to each other by at least three non-colinear connecting blocks, said measuring block being positioned between said side members and supported from at least one of said side members.

Claim 14

The precision square of claim 10 in which said connecting blocks are welded to said side members.

Claim 15

The precision square of claim 11 in which said connecting blocks and said side members are stress relieved.

Claim 16

The precision square of claim 12 in which said surface-engaging means comprises four buttons, and said buttons and said measuring block are made of hardened steel which has not been stress relieved.

Claim 17

The precision square of claim 13 in which said buttons are attached to at least two of said connecting blocks.

Claim 18

The precision square of claim 14 in which said measuring block is attached to at least two of said connecting blocks by bolts.

Claim 19

A precision square comprising a measuring block having two parallel measuring surfaces disposed on opposite sides thereof adapted to receive a measuring instrument, surface-engaging means in fixedly disposed relation to said measuring surfaces accurately defining a plane substantially perpendicular to said measuring surfaces, said surface-engaging means comprising four buttons which are adapted to accurately engage a nominally vertical surface at a plurality of spaced-apart locations, first suspending means for hanging said square in a first orientation, second suspending means for hanging said square in a second orientation, said second orientation being displaced from said first orientation by 180*, said first and second suspending means being arranged so that the same plurality of locations on said nominally vertical surface is engaged when said square occupies its first and second orientations, and two parallel side members connected to each other by at least three non-colinear connecting blocks, said measuring block being positioned between said side members and supported by two of said connecting blocks, each of said suspending means comprising means forming a ramp located on a different one of said connecting blocks adapted to be engaged by a hanger for suspending said square in its first and second orientations.

Claim 20

A precision square comprising a measuring block having two parallel measuring surfaces disposed on opposite sides thereof adapted to receive a measuring instrument, surface-engaging means in fixedly disposed relation to said measuring surfaces accurately defining a plane substantially perpendicular to said measuring surfaces, said surface-engaging means comprising four buttons which are adapted to accurately engage a nominally vertical surface at a plurality of spaced-apart locations, first suspending means for hanging said square in a first orientation, second suspending means for hanging said square in a second orientation, said second orientation being displaced from said first orientation by 180*, said first and second suspending means being arranged so that the same plurality of locations on said nominally vertical surface is engaged when said square occupies its first and second orientations, and two parallel side members connected to each other by at least three non-colinear connecting blocks, said measuring block being positioned between said side members and supported by two of said connecting blocks, each of said suspending means comprising means forming a ramp located on a different one of said connecting blocks adapted to be engaged by a hanger for suspending said square in its first and second orientations.

Claim 21

The precision square of claim 16 in which each of said ramps is arranged so that a line taken perpendicular to the ramp and near its center passes through a line connecting the centers of the two nearest buttons.

Claim 22

The precision square of claim 16 in which each of said ramps is arranged so that a line taken perpendicular to the ramp and near the center of the area of the ramp engaged by a hanger passes through a line connecting the centers of the two nearest buttons.

Claim 23

The precision square of claim 16 in which at least one stiffening member is positioned between said side members.

Claim 24

The precision square of claim 19 in which a handle is attached to at least one of said side members, said handle being made of a material which has a low coefficient of thermal conduction.

Claim 25

A square comprising two parallel plate-like side members, at least three spaced non-colinear connecting blocks located between and attached to said side members, surface-engaging means supported by two of said connecting blocks for accurately engaging a nominally vertical surface, said two connecting blocks which support said surface-engaging means each having provided thereon a suspending means for hanging said square in a position in which said surface-engaging means engages the nominally vertical surface, the orientations of said square in the two positions in which said square is hung by said two suspending means being displaced from each other by 180*, and a measuring block having two measuring surfaces disposed on opposite sides thereof adapted to receive a measuring instrument for determining the deviation from the vertiCal direction as defined by gravity, said measuring surfaces being parallel to each other and perpendicular to a plane defined by said surface-engaging means, said measuring block being positioned between said side members and supported from at least one of said side members.

Claim 26

A square comprising two parallel plate-like side members, at least three spaced non-colinear connecting blocks located between and attached to said side members, surface-engaging means supported by two of said connecting blocks for accurately engaging a nominally vertical surface, said two connecting blocks which support said surface-engaging means each having provided thereon a suspending means for hanging said square in a position in which said surface-engaging means engages the nominally vertical surface, the orientations of said square in the two positions in which said square is hung by said two suspending means being displaced from each other by 180*, and a measuring block having two measuring surfaces disposed on opposite sides thereof adapted to receive a measuring instrument for determining the deviation from the vertiCal direction as defined by gravity, said measuring surfaces being parallel to each other and perpendicular to a plane defined by said surface-engaging means, said measuring block being positioned between said side members and supported from at least one of said side members.

Claim 27

The square of claim 21 further comprising a means for vertically orienting said square within the plane of the nominally vertical surface so that one of said surface engaging means is positioned directly above the other surface engaging means.

Claim 28

The square of claim 22 in which said means for vertically orienting said square within the plane of the nominally vertical surface comprises at least one spherical bubble level.

Claim 31

The device of claim 24 in which said hanger comprises two spaced magnetic retaining means connected by a bar, said bar having a hanging element for engaging said two suspending means.

Claim 34

The precision square of claim 10 in which said measuring block is supported by two of said connecting blocks.

Claim 35

The precision square of claim 10 in which each of said suspending means comprises means forming a ramp supported from at least one of said side members.

Claim 36

The square of claim 21 in which each of said two suspending means comprises means forming a ramp.

Claim 37

The device of claim 25 in which said hanging element comprises means forming a ramp, and each of said suspending means comprises means forming a ramp adapted to engage said hanging element ramp means so as to urge said square against the nominally vertical surface.

Claim 38

The device of claim 24 in which said hanger comprises means forming a ramp, and each of said suspending means comprises means forming a ramp adapted to engage said hanger ramp means so as to urge said square against the nominally vertical surface.