Techniques for measuring a position of a build platform in an additive fabrication device are provided. Such techniques may include detecting the onset and/or dissipation of force applied to a build platform as it moves from being in contact with, to being out of contact with, a container. In some embodiments, the techniques described herein may be applied in a stereolithographic additive fabrication device. According to some embodiments, measurement of forces applied to a build platform may be used to provide for reliable and consistent measurements of the height of the build platform relative to a container by measuring such forces at various positions of the build platform and analyzing the pattern of the forces with distance from the container.

Probes are provided with caps, the caps comprise rolling bearing elements so that the probes can be slid along a surface to be measured, without damaging the surface or wearing away the tip of the probe or a sacrificial cap. The rolling bearing elements can be arranged in a ring around the probe tip, with the plane of the foremost edges of the rolling bearing elements a predetermined distance from the probe tip. The caps can comprise a housing with a grip, to encourage users to grip the cap, which comprises the rolling bearing elements, rather than the probe.

An apparatus for checking the length (H) of a chamfer (7) delimited by a first surface (5) and by an edge (S), comprises two feelers (15, 25)—movably connected to a same supporting frame (20)—and respective transducers (16,26). The transducers supply signals (T1, T2) indicative of displacements of the respective feelers along mutually perpendicular directions (Y, X). A checking method includes moving the supporting frame at a constant speed so that, during the movement, one of the feelers scans the chamfer and the other cooperates with the first surface. The signals of the respective transducers are acquired and transmitted synchronously to a processing unit (40) which processes them together with information on the mutual position of the two feelers to obtain the length of the chamfer.

An apparatus for checking the length (H) of a chamfer (7) delimited by a first surface (5) and by an edge (S), comprises two feelers (15, 25)—movably connected to a same supporting frame (20)—and respective transducers (16,26). The transducers supply signals (T1, T2) indicative of displacements of the respective feelers along mutually perpendicular directions (Y, X). A checking method includes moving the supporting frame at a constant speed so that, during the movement, one of the feelers scans the chamfer and the other cooperates with the first surface. The signals of the respective transducers are acquired and transmitted synchronously to a processing unit (40) which processes them together with information on the mutual position of the two feelers to obtain the length of the chamfer.

Described is a feed mechanism for a slider which is convenient to use with good durability and low costs by eliminating a rack-and-pinion method. The feed mechanism allows the slider to be fed and moved along a longitudinal main scale. The feed mechanism includes a driving gear that is a gear train pivotally supported by the slider, a driven roller that meshes with the driving gear and rotates by rotation of the driving gear, and an arm that includes a cup portion capable of receiving the driven roller on a distal end. The arm includes the cup portion capable of receiving the driven roller on the distal end and is pivotally supported by the slider on a base end. The cup portion in a state of receiving the driven roller is biased toward the main scale by a pin plunger. Accordingly, the driven roller is kept abutted against the main scale.

A measurement device is provided for measuring a resected femoral head. The device comprises a base (102) with a support rod (104) extending transversely from the base and extending in a direction corresponding to a height of a resected femoral head. A femoral head support (108) is attached to a base proximate an end of the support rod (104) for supporting a severed end of a femoral head at a selected incline between about 30° and 60° relative to the base such that a height of the resected femoral head extends in the general direction of the support rod. A transverse height indicating arm (120) is adjustable up the height of the support rod (104) so as to measure the height of a resected femoral head (106) positioned on the femoral head support in use. The transverse height indicating arm (120) may carry adjustable offset indicating arm (122).

The present invention discloses a flexible method and apparatus for thickness measurement. The apparatus includes seven parts: a measurement host, an etalon, a tested piece, a test piece positioning support, a driver, and a digital controller. The measurement host includes a rack, a coding lead screw, and a dual-acting cantilever sensor. The coding lead screw includes a micro-metering lead screw and a tri-state encoder. The tri-state encoder includes a fluted disc and four pairs of cantilever sensors. The dual-acting cantilever sensor includes left and right mobile cantilever sensors with a pair of clipping pin. The digital controller contains system measurement software.

The present disclosure provides a blade inspection device, a method and a printing modification device, and belongs to the technical field of screen printing. The blade inspection device includes a telescopic component, a driving component and a parameter obtaining module. The driving component is configured to drive the telescopic component to move in a direction parallel to the line where the blade is located. The parameter obtaining module is configured to obtain a first parameter to inspect the blade according to the first parameter. The first parameter is related to a displacement of the first end of the telescopic component in a direction perpendicular to the line where the blade is located.

A method of manufacturing a tubular component including rough machining the exterior surface of a solid billet 1 to reduce the size thereof and form two flanges. An axial blind bore 6 is then machined in the billet 1, after which a probing operation is carried out on the interior surface of the bore 6 in order to check the concentricity. A straightening operation is then performed on the billet in order to reverse any curvature along the longitudinal axis. A further machining operation is then performed on the outside to reduce the wall thickness of the bore before measuring the wall thickness of the bore 6 around the circumference of the billet 1 at least at two different axial positions. The billet 1 is then checked again and a final machining operation is then performed in order to form any ports and upstands which are required.

A method of manufacturing a tubular component including rough machining the exterior surface of a solid billet 1 to reduce the size thereof and form two flanges. An axial blind bore 6 is then machined in the billet 1, after which a probing operation is carried out on the interior surface of the bore 6 in order to check the concentricity. A straightening operation is then performed on the billet in order to reverse any curvature along the longitudinal axis. A further machining operation is then performed on the outside to reduce the wall thickness of the bore before measuring the wall thickness of the bore 6 around the circumference of the billet 1 at least at two different axial positions. The billet 1 is then checked again and a final machining operation is then performed in order to form any ports and upstands which are required.