Abstract: A tool (12) is releasably supported on a head (10) by a kinematic support (35) having elements (36,37) provided respectively on the head (10) and the tool (12) and extending in a plane (A--A) transverse to an axis (10A) of the head (10) by a releasable coupling (17) which comprises a first element (21) provided on the head (10) and engaged with a second element (26) provided on the tool. To release the tool (12) from the head (10) the latter is moved to position the tool (12) at a magazine (16) and by such movement to connect the second element (26) with an operating member (41) provided on the magazine (16). Rotation of the second element (26) by the operating member (41) releases the second element (26) from the first element (21) and frees the head (10) for withdrawal in the direction of its axis (10A).

Abstract: A numerically controlled machine tool capable of milling and turning operations has a continuously rotatable first spindle (10) to which is releasably secured a work holder (50). A rotationally positionable second spindle (20) has releasably secured thereto a tool holder (60). For turning operations, the second spindle (20) is locked against rotation and has secured thereto a tool holder having a turning tool (61), the workpiece (51) being held by the work holder on the first spindle (10). For milling operations, the second spindle (20) is unlocked, the work holder (50) is secured to the second spindle (20), and a tool holder (60) with a milling tool therein is secured to the first spindle (10). The changeover of work and tool holders is done by a transfer mechanism which takes appropriate holders (60), as well as work blanks, from a magazine system.

Abstract: The machine tool is a machining center having an angularly positionable tool spindle 16, a work table 11 movable relative to the spindle, and a surface-sensing probe 25 mountable on the spindle for measuring dimensions or positions on a work piece situated on the table. The probe senses a surface when the latter lies a small distance ("the probe offset") away from the spindle axis.The method comprises providing on the workpiece a bore 24 defining opposite test surfaces -DX and +DX. The mid-point between the test surfaces has a known nominal position but an unknown actual position. The method further comprises operating the machine in a specified way to measure the test surfaces, the operation including rotating the spindle through 180.degree. between certain of the measuring operations. The measurements are then used for computing the probe offsets and the distance ("the work offset") between said nominal and actual positions.

Abstract: A numerically controlled machine tool has a rotatable spindle (10) to which is connected, in the place of the usual cutting tool, a probe (16) for measuring a work surface (25) to be, or having been, machined by a said tool. The probe (16) includes an electric circuit (30) adapted to respond to engagement between the probe (16) and the work surface (25), by disestablishing a signal (26) to a control system (12) and thereby effect measurement of the position of the work surface (25). The circuit (30) is energized by a battery (31) normally disconnected from the circuit (30) and connectable thereto by the control system (12) effecting a transient rotation of the spindle (10). The rotation acts on a centrifugally operated, normally open switch (FIG. 2) arranged within the probe (16). The circuit (30) is arranged to latch the switch in the "on" condition when the transient rotation ceases whereafter the probe (16) is ready for the probing operation.

Abstract: In a co-ordinate measuring machine a probe is connected to the head of the machine by a pivotal arm, and the orientation of the probe is changed by moving the head so that the arm engages a fixed structure and a moment is applied to the arm which is thereby caused to turn and present the probe in the required orientation.

Abstract: The machine tool is a machining center having an angularly positionable tool spindle, a work table movable relative to the spindle, and a surface-sensing probe mountable on the spindle for measuring dimensions or positions on a work piece situated on the table. The probe senses a surface when the latter lies a small distance ("the probe offset") away from the spindle axis.The method comprises providing on the workpiece a bore 24 defining opposite test surfaces -DX and +DX. The mid-point between the test surfaces has a known nominal position but an unknown actual position. The method further comprises operating the machine in a specified way to measure the test surfaces, the operation including rotating the spindle through 180.degree. between certain of the measuring operations. The measurements are then used for computing the probe offsets and the distance ("the work offset") between said nominal and actual positions.

Abstract: A machine tool spindle (10), rotatable in a housing (11), is adapted to receive, as an alternative to a cutting tool, a probe (12) having a stylus (14) whereby to sense a workpiece (15) for the purpose of measuring it. On sensing the workpiece (15) the probe (12) generates a signal which is transmitted to a fixed location (X) on the housing (11). The probe (12) has a body (13) secured to the spindle (10) for rotation therewith, such rotation being required for certain measuring manouvres. To cope with the transmission of the signal (17) from the rotating probe (12) to the fixed location (X), the signal (17) is transmitted through the intermediary of a sleeve (19) supported on the probe body (13) such that the body (13) can rotate while the sleeve (19) is held still by an axially disengageable mechanical connector (21) connecting the sleeve (19) to the housing (11).

Abstract: A probe for sensing the position of a workpiece comprises a housing adapted to be secured to a coordinate measuring machine. A stylus projecting from the housing is engageable with the workpiece for sensing the position thereof. The stylus is secured to a moveable member supported within the housing by three bellows having mutually perpendicular axes and each secured to the moveable member and the housing in position therebetween. Since a bellows is inherently stiff in torsion about its axis but is flexible axially and transversely, the bellows cooperate to constrain the stylus for parallel motion. More particularly, any one first bellows can expand or contract to accommodate movement of the stylus in the direction of the axis of that the first bellows, a second one of the bellows prevents tilting of the stylus by virtue of its torsional stiffness. At the same time both the second and third bellows flex transversely to accommodate the expansion or contraction of the first bellows.

Abstract: A numerically controlled machine tool comprises a tool movable into engagement with a workpiece, means for generating a first signal being a measure of the distance between the tool and a datum surface provided on a relatively fixed part of the machine, a first closed loop system adapted to move the tool toward the workpiece and having the first signal as feedback, means for generating a second signal being a measure of the distance between the tool and the workpiece, a second closed loop system (33) having the second signal as feedback, and means responsive to the second-mentioned distance attaining a threshold value, while being moved under the control of the first system, for changing control of the tool movement from the first to the second system.

Abstract: A probe for use in measuring apparatus has a base member including a two-dimensional seat for an intermediate member which, in turn, includes a two-dimensional seat for a stylus holder. The two seats face in opposite directions so that the stylus holder can be displaced from the seated position in either of two opposite directions.

Abstract: A probe for measuring dimensions of a workpiece in coordinate positioning apparatus, comprises a base (20), a stylus holder (21) having an axis (21A), an intermediate member (22, 30) having a fixed region (22A) connected to said base and a free region (22B) connected to said holder, said intermediate member being resilient so as to be responsive to a displacing force (FW) acting on said holder in the sense tending to tilt or axially move said holder relative to said base, and sensing means (30) connected between said free region and said base for sensing the occurence of a said displacing force.The intermediate member is only sufficiently resilient to make possible said sensing.

Abstract: A probe for use in measuring apparatus has a base member including a two-dimensional seat for an intermediate member which, in turn, includes a two-dimensional seat for a stylus holder. The two seats face in opposite directions so that the stylus holder can be displaced from the seated position in either of two opposite directions.

Abstract: A probe having a movable member including an elongate stylus and a plate extending in a plane transverse to the longitudinal axis of the stylus. The plate is seated on a seat having a circular edge provided on the fixed member. Displacement of the free end of the stylus, either transversely to or longitudinally of the stylus, is measured by a transducer having an electrical output signal. Like transverse and longitudinal displacements of the free end unavoidably produce unlike signals. To compensate for this, the signal is passed through a voltage divider whose output is made variable by a relay in a circuit containing the plate and the edge as electrical contacts. Transverse displacement of the free end tilts the plate on the edge, thus maintaining engagement therebetween. Longitudinal displacement separates the plate from the edge, thus breaking contact therebetween.

Abstract: A probe for use in measuring apparatus has a base member including a two-dimensional seat for an intermediate member which, in turn, includes a two-dimensional seat for a stylus holder. The two seats face in opposite directions so that the stylus holder can be displaced from the seated position in either of two opposite directions.

Abstract: A method and apparatus for measuring a dimension of a workpiece mounted on a numerically controlled machine tool having a probe for sensing the surface of the workpiece, an automatic means for moving the probe relative to a datum, the automatic means including a first measuring means for producing a signal defining units of distance corresponding to the relative movement of the probe with respect to the datum, and a second measuring means coupled to the first measuring means for accumulating a count corresponding to the relative movement of the probe in respect to the datum. The actual position of the workpiece surface is determined relative to a nominal position thereof, the nominal position being at a known distance from the datum. According to the method the probe is moved to a first position which is one of the actual and nominal positions of the workpiece surface.

Abstract: A contact-sensing probe has a movable member including a stylus and is supported on a fixed member at two spaced-apart locations. At each location a spherical element on the one member is situated between convergent surfaces of the other member. A spring urges the movable member into engagement with the fixed member so that at each location the element slides on the convergent surfaces and by virtue of the convergence thereof attains a positive rest position therebetween. The movable member is displaceable from the rest position against the force of the spring when a force is applied to the stylus and is returnable into the rest position by the spring. The elements and surfaces may be electrical contacts, displacement of the stylus being sensed by any one of the contacts being broken. Alternatively displacement is sensed by a proximity sensor.

Abstract: A probe for use in measuring apparatus has a base member including a two-dimensional seat for an intermediate member which, in turn, includes a two-dimensional seat for a stylus holder. The two seats face in opposite directions so that the stylus holder can be displaced from the seated position in either of two opposite directions.

Abstract: Apparatus for monitoring the state of a first circuit (19) by means of a second circuit (29) has an inductive coupling (23) linking the circuits across a gap (32). The second circuit embodies an oscillator (27) producing primary oscillations in that circuit and, through the coupling, secondary oscillations in the first circuit (19). If the state of the first circuit (19) is changed as by opening or closing of contacts (17,18), the resulting change in the impedance of the first circuit results in a change in the frequency of the primary and secondary oscillations. The second circuit (29) is connected to a detector (35) producing a signal (37AI) when the frequency changes. Instead of an inductive coupling, a capacitative coupling may be used.The apparatus is described as applied to a machine for measuring length. The first circuit (19) is embodied in a probe (12) whereby the machine contacts a workpiece to be measured. The first circuit is opened by such contact.

Abstract: In a co-ordinate measuring machine a probe is connected to the head of the machine by a pivotal arm, and the orientation of the probe is charged by moving the head so that the arm engages a fixed structure and a moment is applied to the arm which is thereby caused to turn and present the probe in the required orientation.

Abstract: A contact-sensing probe has a movable member including a stylus and is supported on a fixed member at two spaced-apart locations. At each location an a spherical element on the one member is situated between convergent surfaces of the other member. A spring urges the movable member into engagement with the fixed member so that at each location the element slides on the convergent surfaces and by virtue of the convergence thereof attains a positive rest position therebetween. The movable member is displaceable from the rest position against the force of the spring when a force is applied to the stylus and is returnable into the rest position by the spring. The elements and surfaces may be electrical contacts, displacement of the stylus being sensed by any one of the contacts being broken. Alternatively displacement is sensed by a proximity sensor.