Abstract: A capacitive measuring device or apparatus; in particular, a length-measuring apparatus, which incorporates a scale portion and a scanning unit which is movable relative to the former and which supports transmitting electrodes and at least one receiving electrode. Herein, a transmission circuit applies transmitting signals at a basic frequency to the transmitting electrodes, and with the receiving electrode being connected to a reception circuit, to the output side of which there is connected an evaluating circuit for the receiving signals. The transmitting signals are applied to the transmitting electrodes through a pulse width modulator and a synchronous modulator and the receiving signal is conducted through a demodulator.

Abstract: The apparatus comprises a bearing plate (1), a slideway (2) and a girder (3) which are perpendicular to the bearing plane of the bearing plate, a slide (4) with tracer head (5) movable along the slideway and a drive plate (7) located in front of the slide and stabilized by guides (8, 9) independent of the slide. The plate (7) and the slide (4) are connected by balancing (10) and damping (11) springs. A drive device by cable (13) and return pulleys (15-18) which is moved by a movement generator (19) is connected to the plate (7) and is entirely supported by the girder (3) and the bearing plate (1). A counterweight (14) inserted in the circuit of the cable (13) balances the weight itself of the movable elements (4, 7). A body (63) for protection against impacts is fastened to the girder (3) and to the bearing plate (1).

Abstract: The sensor has at least one sensor unit arranged opposite an incremental measurement scale (1) with reflecting graduation (2). The sensor unit comprises a photoemitter (3) and an adjacent photoreceiver (4), located in a printed circuit (6), with optical axes (xx') parallel to each other and perpendicular to the plane of the scale (1), and an optical group (9) with two focusing lenses (10, 12) and two deflection faces (11, 13) integrated by molding in a support of transparent synthetic material. In the optical group, one of the two lenses and one of the two deflection faces are aligned on each of the two said optical axes (x, x') in order to direct and deviate the light rays coming from the photoemitter (3) and to recover them on the photoreceiver (4) after their passage through a graduated sensing graticule (14).

Abstract: The device, shown associated with a bore measuring machine, comprises two elements in engagement in the form of a bolt (20) and a nut (21) of reversible relative axial rotation and displacement. The bolt (20) is a threaded cylindrical sleeve mounted coaxial to the measurement rod (4) of the machine and with free rotation between two stops (9, 23) thereof, and the nut (21) is formed by an inner thread on the cylindrical body (1) of the machine. The force of friction developed by the relative bolt-nut rotation is adapted to yield to at least the pressure of the return spring (7) of the measurement rod and to constitute a brake for modulating the speed of the displacements in both directions of the measurement rod (4) in the body of the machine.

Abstract: The sensor is of the type having a cylindrical body within which a measurement rod equipped with an outer measurement feeler bears a ferrite core which by its displacements influences the impedance of a system of coils to produce an electrical measurement signal. In the body, a fixed stop and an interposed movable stop make it possible to adjust the positioning of the measurement feeler in one or the other of two positions with respect to the electrical zero of the feeler and they have for this purpose interpenetration means with two stages spaced at an angle from each other and selected by manual push and rotation of the rod driving the movable stop in opposition to a spring and then release, in the manner of the so called "bayonet" connections.

Abstract: The feeler comprises a stationary support (1) and a movable support (4) provided with a tip (5), which are pressed against each other by a spring (21). The immobilizing of the movable support with respect to the stationary support is obtained by a system of connections with zero degree of freedom formed of four spherical positioning pieces (7 to 10) applied, by six contact points, to six inclined resting surfaces (15 to 20) with flat contact surface, two first pairs (15-16, 17-18) of which are convergent and arranged respectively under two first opposing positioning pieces (7, 8) and the last two of which (19, 20) are parallel and each arranged under one of the two other opposing positioning pieces (9-10). An electrical circuit is provided to detect any interruption of contact between at least one positioning piece and one resting piece signifying an encounter of the tip (5) with the object.

Abstract: The device comprises a sensor (2) which is connected to a movable housing (1) by an elastically deformable mechanism (4).The sensor and the housing are connected to an electric circuit (5) comprising:a capacitive amplifier producing a measurement pulse constituting a datum for a computer and an order for the stopping of the displacement of the sensor when the latter comes into contact with a part to be measured which is mounted in insulated fashion on a measurement table,a short-circuiting device (17-18) producing a safety pulse which constitute an order for the stopping of this displacement in the event of deformation of the mechanism (4) as a result of the non-issuance of the measurement pulse.A measurement is thus taken with full safety without deformation of the linking mechanism and without the part to be measured having to be connected to the electric circuit.

Abstract: The sensor comprises a reference body (1) in which there is displaceably mounted a movable body (3) bearing a measurement finger (6) and a pick-up (9) which translates the displacements of the movable body into electrical signals.The movable body (3) has a stop (18) subjected to the opposing pressures of two springs (19, 26), one of which (26) lies in the extension of the rod of the piston (24) of a single-acting pneumatic cylinder-piston unit (23).When the cylinder-piston unit is at rest, the measurement finger is disengaged by pressure of the spring (19) opposite said cylinder-piston unit.When the cylinder-piston unit is extended, the measurement finger is pressed against the part to be measured by the action of the spring (26) borne by the rod of the piston.The finger of this sensor is thus disengaged in the position of rest of the cylinder-piston unit and can easily be brought towards the finger of another sensor of the same type in the direction of the taking of the measurement.

Abstract: The instrument is a slide caliper with inner and outer feelers borne by a slideblock (3) and by a slider (6) which is mounted for sliding on the slideblock via a play take-up device (7).That device comprises a base plate (10) having two symmetric end inclined planes (14) on which two shoes (11) are arranged. The base plate bears a central shoulder (16) pierced by a hole (17) in which there is engaged the stud (25) of a drive and locking screw. Two compression springs (12) are interposed between this shoulder and the two shoes in order to cause the latter to rise on the inclined planes.This device automatically takes up the play formed by the sliding system. It is irreversible.The shoes (11) are narrower than the base plate and means (22) are provided to avoid their rubbing against the walls of the slider.

Abstract: The device comprises a scale (1) and a slide (2) which are provided with electrodes arranged to form two pairs of capacitances for the measurement of the displacement of the slide on the scale (CA.sub.1 -CA.sub.2, CB.sub.1 -CB.sub.2). These measurement capacitances are connected to an electronic feed and processing circuit (3) in which they are connected in a bridge (4A, 4B) with switched reference capacitances of MOS type. In this circuit, the outputs of these bridges are connected via comparators (5A, 5B) to a processor (6) of CMOS type adapted to produce a terminal digital measurement signal by counting the periods of the signal of the measurement capacitances and by numerical interpolation within each of these periods. This interpolation is effected by balancing the capacitive bridges by means of a digital algorithm.

Abstract: The apparatus comprises a body (1) provided with three point-contact feelers (12, 13) which open under the action of a spring (19) and close under the action of a lever (20) via a rod (14) and a spacer stop (15). A displacement pick-up (22) and an electronic circuit (25) convert the displacement of the feelers into a measurement signal which is representative of the diameter of the circle which they define. The electronic circuit comprises a minimum memory (31) to memorize the minimum value of the measurement signal, a member (39) for displaying this value (39) and a measurement-initialization switch (32). After the feelers, folded together, have been introduced into the bore, the lever is released, the switch is actuated, and the apparatus is moved in all directions by the operator in order to cause the plane of the feelers to pass in a diametral plane of the bore, this passage generating the minimum value displayed which is representative of the actual diameter of the bore.

Abstract: An instrument composed of a measurement head (1) and a fixed stop (2) which are connected by a body (3) formed of interchangeable extension pieces (4, 5), the instrument being intended to check the dimensions of bulky parts.The two contact stops (12) of this instrument are offset at the end of two parallel measurement feelers (10, 11).With each of these two contact members there is associated an instrument for measuring their inclination, which consists of an electronic clinometer (25, 26).The two clinometers are connected to an apparatus (30) for reading the inclination of the two measurement feelers.The inclination of one of the two measurement feelers (11) is adjustable by means of an operating screw (17).In this way it is possible to reestablish parallelism of the measurement feelers when the instrument bends, upon measurements of large dimensions.

Abstract: An instrument for the measurement and verification of linear dimensions includes a body equipped with external and internal feelers, a perch mounted in a slideway in the body and equipped with external and internal feelers cooperating with those of the body, and independent depth gauge mounted in a second slideway of the body, and a feeler rod mounted in a third slideway of the body, and cooperating with a contact piece fastened with an inner face of the external feeler of the perch. A movable member of a measurement transducer is selectively connected to the perch, to the gauge and to the feeler rod by a selective coupling device. In turn, a display device with zeroing control is connected to the measurement transducer.

Abstract: A hand-held interior gauge for measuring a bore includes a body provided with a measuring head capable of being introduced into the bore, and a measuring transducer connected to a movable feeler and adapted to produce output signals representative of the displacement of the movable feeler. The gauge also includes a mechanism for immobilizing the measuring head while in the bore, such that the feeler is movable angularly and radially in a surface limited by a circumference contained in a plane perpendicular to the axis of revolution of the bore, once the measuring head is immobilized. A driving mechanism forming a portion of the interior gauge coordinates the angular and radial movement of the movable feeler, and the output signals from the feeler are provided to a calculator which, in turn, provides intelligence information to an automatic display device for displaying the diameter of the bore.

Abstract: In a precision dial measuring instrument having a coil-spring shock-absorbing movable unit provided between a pinion and a coaxial gear wheel of the transmission step-up mechanism arranged between the movable indicating member and the feeler of the instrument, the transmission step-up mechanism further includes a system for taking up of play by preliminary elastic stress of its train gear wheels.

Abstract: A shock absorbing device for use in dial measuring instruments comprising a balance lever interposed between a pinion and a coaxial toothed wheel of the multiplier mechanism disposed between the movable indicator member and the movable feeler of the instrument, said balance lever being pivoted on the common axis of said pinion and toothed wheel and intercepting during its pivotal movement in one and the same direction a first radial driving finger integral with an arm connected to the pinion and a second radial driving finger integral with said toothed wheel, a resilient liaison being formed between the balance lever and the radial driving fingers by the opposed action of the ends of at least a spiral spring connected at its inner end to said balance lever.

Abstract: An adjustable fork gauge including a main body having a slide on which a first, fixed jaw is slidably and adjustably mounted and formed from a block having an anvil with a plane face integral with said block; a second, spring clamping jaw adapted to press a plane or cylindrical portion of a part to be measured on the anvil of the fixed jaw; a feeler rod for the part to be measured including a contact adapted to emerge from the clamping jaw and displaceably mounted for translation in a bearing of the body such tha the axis of said feeler rod is perpendicular to the plane of the anvil of the fixed jaw; and a measuring or indicating transducer coupled to the body and having a movable element connected to the feeler rod.

Abstract: In a micrometer head for an instrument for measuring internal dimensions there is included a casing in which at least one measurement contact piece having an inclined base is radially mounted in a slot or groove. The contact piece is driven by the axial displacement of a measuring cone and is maintained in contact with the inclined lateral surface of the cone by means of a return member. The axial displacement of the measuring cone, the base of which is guided in an axial cylindrical recess of the casing, is effected by the thrust of a spindle which has a micrometer screw mounted thereon, the screw being engaged in a threaded member connected to the casing. The cone and spindle have coaxial axes of rotation, and the cone, spindle and micrometer screw are so arranged that the path of movement of the inclined base of the contact piece on the cone is in the form of a tapered ramp having a long length and shallow inclination, the movement being caused by the combined axial and rotational movement of the cone.

Abstract: A measurement instrument in the form of a plug gage comprises a tubular body within which there is centered an axially movable rod, one end of which is intended to transmit the axial movements of said rod to a transducer system connected to the tubular body, while the other end thereof bears a conical part coaxial with said rod, with the lateral surfaces of the conical part resting against radially movable feeler balls, each of which is housed in a guide channel transverse to the longitudinal axis of the tubular body. The plug gage is characterized in that the tubular body bears over at least a portion of its length a coaxial centering sleeve which is removable and interchangeable, this sleeve being provided with transverse openings intended to permit the passage of the balls.

Abstract: A centering and measuring head for measuring machines, comprising a tubular body in which a piston is slidably mounted and subjected to the continuous action of biassing means, at least two centering contact pieces mounted to pivot on shafts provided in the body tangentially on an imaginary circle concentric with the axis of the piston, the movements of the said centering contact pieces being controlled by the said piston, and means for monitoring the displacements of the piston against the action of the biassing restraining element.