Measurement head
AssigneeCarl-Zeiss-Stiftung
InventorsWalter Werner, Klaus Herzog, Franz Szenger
Life of this patent
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Abstract
The invention contemplates an improved work-contacting probe for use in a measuring machine wherein the relationship between contacted locations on a workpiece are reduced to coordinate digital data. The various described probe embodiments feature means whereby positional errors due to probe flexure upon work contact are substantially reduced, as compared to pre-existing structures.
Claims24
A measurement head for determining the coordinates in space of any points of a workpiece moved relative to the measurement head, comprising a mounting part and a movable part, said mounting part being adapted to be fixedly mounted and having means establishing a fixed reference plane of probe support, whereby a fixed reference axis is also established normal to said plane, said movable part having a probe axis which in a position of rest is aligned with said fixed reference axis, coupling means tiltably and yieldably supporting said movable part with respect to said mounting part and permitting said movable part and its probe axis to tilt with respect to said fixed reference axis, said coupling means including loading means axially operative to normally urge said movable part into said position of rest wherein said movable part is in a precise position in space with respect to said mounting part, said movable part consisting of a base member and a probe member connected to each other via one or more measuring elements which are highly sensitive to tension and compression, said base member being the means whereby said movable part is tiltably and yieldably supported.
Measurement-head structure for mounting a work-contacting probe in a machine for ascertaining coordinate data pertaining to selected surface points on a workpiece, said structure comprising a base member adapted for fixed mounting to a probe-supporting part of the machine and having means establishing a fixed reference plane of probe support, whereby a fixed reference axis is also established normal to said plane, an intermediate member tiltably and yieldably supported by and with respect to said base member and having an at-rest position determined by said reference plane of probe support, means acting in the direction of said axis and normally loading said intermediate member into said at-rest position and therefore into a precise position in space with respect to said base member, a work-contactable probe member, and coupling means securing said probe member to said intermediate member with one or more electrical elements interposed between said probe member and said intermediate member, said probe member being in alignment with said axis when said structure is in at-rest condition, said probe member extending for probe-to-work contact at axial offset from said plane, and said one or more electrical elements being highly sensitive to tension and compression;
- whereby said one or more electrical elements is instrumental in determining precisely such initial workpiece contact by said probe member as to cause slight tension and/or compression of said one or more electrical elements.
Measurement-head structure for mounting a work-contacting probe in a machine for ascertaining coordinate data pertaining to selected surface points on a workpiece, said structure comprising a base member adapted for fixed mounting to a probe-supporting part of the machine and having means establishing a fixed reference plane of probe support, whereby a fixed reference axis is also established normal to said plane, an intermediate member tiltably and yieldably supported by and with respect to said base member and having an at-rest position determined by said reference plane of probe support, means acting in the direction of said axis and normally loading said intermediate member into said at-rest position and therefore into a single precise position in space with respect to said base member, and a work-contactable probe member secured to said intermediate member, said probe member consisting of two parts which are connected to each other via interposed one or more measurement elements which are highly sensitive to tension and compression, and said probe member being in alignment with said axis when said structure is in at-rest condition, said probe member extending for probe-to-work contact at axial offset from said plane;
- whereby said measurement elements are instrumental in determining precisely an initial workpiece contact by said probe member, such contact causing said two parts of said probe member to move slightly with respect to each other thus causing tension and/or compression forces upon said measurement elements for development of an initial characterizing pulse.
Measurement-head structure for mounting a work-contacting probe in a machine for ascertaining coordinate data pertaining to selected surface points on a workpiece, said structure comprising a base member adapted for fixed mounting to a probe-supporting part of the machine and having means establishing a fixed reference plane of probe support, whereby a fixed reference axis is also established normal to said plane, coupling means including a tiltable and yieldable member supported by and with respect to said base member and having an at-rest position determined by said reference plane of probe support, means acting in the direction of said axis and normally loading said coupling member into a precise position and orientation in space with respect to said base member, a work-contactable probe member coupled to said coupling member, said probe member being in alignment with said axis when said structure is in at-rest condition, said probe member extending for probe-to-work contact at axial offset from said plane, and strain-gage means carried by said coupling member and producing an electrical output signal in response to a stress change in said coupling member, whereby said strain-gage means is instrumental in determining precisely such initial workpiece contact by said probe member as to cause a stress change in said coupling member.
Dependencies are inferred from the claim text.