Abstract: A plurality of segmented chips are reinforced by applying an adhesive to the circumferentially opposite end portions thereof, and the adjoining segmented chips adjoining in the circumferential direction are adhered to the circumferential surface of a disc-like core with the adhesives at the circumferentially opposite end portions being not jointed with each other. Thus, the segmented chips can be prevented from being loaded with an unnatural force even when the disc-like core with the segmented chips adhered thereto expands and contracts radially due to thermal expansion and thermal contract. Thereby, expansion and contraction of the disc-like core do not impose a compression stress or the like on adhesives situated between adjoining segmented chips.

Abstract: A plurality of segmented chips are reinforced by applying an adhesive to the circumferentially opposite end portions thereof, and the adjoining segmented chips adjoining in the circumferential direction are adhered to the circumferential surface of a disc-like core with the adhesives at the circumferentially opposite end portions being not jointed with each other. Thus, the segmented chips can be prevented from being loaded with an unnatural force even when the disc-like core with the segmented chips adhered thereto expands and contracts radially due to thermal expansion and thermal contract. Thereby, expansion and contraction of the disc-like core do not impose a compression stress or the like on adhesives situated between adjoining segmented chips.

Abstract: In a grinding wheel in which abrasive tips for rough grinding and abrasive tips for finish grinding are alternately bonded to a periphery of a disk type base rotating about a rotation axis, each abrasive tip includes the abrasive layer formed by bonding abrasive grains and a lower layer overlaid and integrally for led with the abrasive layer. The abrasive tip is attached to the periphery of the base at the lower layer. A Young's modulus of the lower layer of the abrasive tip for finish grinding relative to a load acting on the grinding surface of the abrasive tip in an inward direction of the grinding wheel is less than that of the abrasive tip for rough grinding. Thereby, the surface of a workpiece can be both rough-ground and finish-ground with superhigh-precision surface roughness with using one grinding wheel.

Abstract: In a grinding wheel in which abrasive tips for rough grinding and abrasive tips for finish grinding are alternately bonded to a periphery of a disk type base rotating about a rotation axis, each abrasive tip includes the abrasive layer for ed by bonding abrasive grains and a lower layer overlaid and integrally for led with the abrasive layer. The abrasive tip is attached to the periphery of the base at the lower layer. A Young's modulus of the lower layer of the abrasive tip for finish grinding relative to a load acting on the grinding surface of the abrasive tip in an inward direction of the grinding wheel is less than that of the abrasive tip for rough grinding.

Abstract: An intelligent machining system employs a neural network for calculating machining conditions on the basis of attribute data or a workpiece and a grinding machine. The system comprises a reference machining condition calculating unit, a neural network which receives the attribute data and provides corrections, and a correcting unit for correcting the reference machining conditions by using the corrections. Corrections which cannot be determined by means of empirical expressions or theoretical expressions are determined appropriately by the neural network previously learned. The system determines corrections for the machining conditions on the basis of machining errors decided by a neural network. The system also detects time-series machining phenomena by sensors, processes the output detection signals of the sensors by a neural network to obtain machining circumstance data. The feed rate of the tool is controlled by a fuzzy inference on the basis of the machining circumstance data.

Abstract: Disclosed is a processing apparatus capable of optimizing its rule base comprising a plurality of rules having an antecedent and a consequent each. The antecedent contains input conditions of machining, and the consequent describes the result of machining. The antecedents are applied to input condition data. The consequents of the applied rules yield machining result data that are evaluated for rule fitness. When the rule base is updated, some rules are deleted and some preserved depending on their degrees of fitness. Between given two rules having the same consequent, any number of corresponding conditional elements in their antecedents are exchanged so as to generate new rules. The process is repeated until the rule base is optimized. With the antecedents of rules applied to input condition data and with the consequents of the applied rules yielding machining result data, those data may be modified according to modification request data.

Abstract: A device for detecting a position of an edge of a cutting tool includes a reference plate positioned to form a slit between the edge of the cutting tool and the reference plate. The slit extends in a direction transverse to the longitudinal direction of the cutting tool. A laser light source is provided to irradiate a laser light to the slit. A detecting device detects a diffraction pattern created through diffraction of the laser light by the slit. A processing device is provided to determine the position of the edge of the cutting tool based on an output signal of the detecting device.

Abstract: A dressing apparatus for dressing an electroplated grinding wheel by crushing the top portions of the abrasive grains thereof. The abrasive grains are diamond grains or CBN grains. A role made of ceramics, or a ferrous role holding diamond grains on its outer periphery is used for crushing the abrasive grains. The grinding wheel is rotated in one direction and the role is rotated in the opposite direction so that the difference in surface speed between the role and the grinding wheel becomes substantially zero. The role is then advanced toward the grinding wheel to crush the top portions of the abrasive grains, so that the heights of the abrasive grains are roughly equalized, and many sharp cutting edges are formed at the top portions of the abrasive grains.

Abstract: A grinding wheel for use in a grinding machine, wherein a plurality of grinding tips are bonded on the periphery of a wheel core having a disk-like shape using a bond which forms a bonding layer between the wheel core and the grinding tips. The grinding wheel is further provided with means for preventing coolant from entering inside of the abrasive layer and/or bonding layer, thereby preventing the bonding layer from being swelling by the coolant. In a first embodiment, the preventing means is composed of rubber layers formed on the both side surfaces of the grinding wheel at the places corresponding to the radial position of the bonding layer. In another embodiment, the preventing means is composed of water-repellant material capable of repelling water. Such material is composed of silicon or fluorine resin and is soaked into the grinding tips.

Abstract: In a centerless grinding machine, a work blade for rotatably carrying a workpiece is movable by a blade feed device in a direction normal to a first line extending across the axes of grinding and regulating wheels. Present diameters of the wheels, a desired finish diameter of the workpiece and a predetermined value representing the sine of a center height angle are stored in a data memory. The center height angle is represented by the sum of angles which a second line extending across the axes of the grinding wheel and the workpiece and a third line extending across the axes of the regulating wheel and the workpiece respectively make relative to the first line when the workpiece is finished to the desired finish diameter. When each of the wheels is dressed, a data rewriting circuit replaces the diameter of each wheel being stored in the data memory with a new diameter after such dressing.

Abstract: A regulating wheel dressing system in a centerless grinder, having a dressing tool for dressing a regulating wheel, which dressing tool is adapted to be feed-controlled in a direction parallel to the axis of rotation of the regulating wheel and also in a crossing direction by a feed control means, which in turn is controlled biaxially simultaneously by a control means. Coordinate values of plural points on a rotated hyperboloid of one sheet of revolution to be formed on the regulating wheel are calculated and the dressing tool is feed-controlled for coordinate interpolation between the plural points with those coordinate values as target points. The regulating wheel can be dressed to the rotated hyperboloid of one sheet of revolution in high accuracy independently of changes of its diameter and even where it is stepped for supporting a stepped work.

Abstract: A truing apparatus includes a truing tool supported on a tool support movable radially and axially of a grinding wheel having a rounded corner and drivable by a feed drive unit coupled to the tool support to move along a predetermined path for truing the rounded corner of the grinding wheel. At least one contact member for contacting outer peripheral and end surfaces of the grinding wheel is mounted on the tool support, and a sensor is also mounted on the tool support for detecting a contact between the contact member and the grinding wheel. A feed control system controls the feed drive unit for moving the truing tool along the predetermined path. The feed control system controls the feed drive unit so that the contact member will move radially and axially of the grinding wheel until the sensor is actuated immediately after one truing process and immediately before a next truing process.

Abstract: An apparatus for truing a grinding wheel includes a stylus movable in response to movement of a truer in synchronism therewith, and a template disposed in confronting relation to the stylus with a gap left therebetween. The truer is controlled in its motion by servomotors driven in response to a command issued from a numerical control unit. When the truer is caused by the numerical control unit to move out of control for some reasons, the stylus is brought into engagement with the template, thereby protecting the truer and a grinding wheel being trued thereby against damage which would otherwise result from such uncontrolled movement of the truer. When the truer is to be advanced for truing infeed against the grinding wheel, the stylus is disconnected by a clutch device from the truer, and only the truer is moved in the forward direction while maintaining a proper gap between the stylus and the template.

Abstract: A grinding machine is provided wherein a pair of wheel slides are disposed respectively at both sides of a work support to be movable toward and away from the work table in a first direction. The wheel slides respectively carry turrets thereon in such a manner that each of the turrets is rotationally indexed about and slidable along an axis thereof extending in a second direction perpendicular to the first direction. Each of the turrets carries a plurality of grinding wheels which are rotatable about respective axes extending in the second direction, and when rotationally indexed selectively presents the grinding wheels to a machining station. The position of a selected one of the grinding wheels relative to a workpiece on the work support is adjusted in the first direction through the movement of each wheel slide and in the second direction through the movement of each turrets.

Abstract: A bed for a grinding machine includes a bed body formed at the upper surface thereof with a coolant receiving portion on which a layer of resin mortar is formed. The resin mortar is formed by a mixture of epoxy resin, a hardner and sand with a weight ratio of approximately 12.2:2.8:85. The bed includes a peripheral wall and the coolant receiving portion is trough shaped and has a flat surface portion so as to communicate with a coolant exhaust conduit.

Abstract: A device for detecting grinding wheel life is provided including a truing tool wear detection device for detecting a total wear amount of a truing tool after every truing operation and an arithmetic and judgement circuit arrangement. The circuit arrangement compensates for the total wear amount by a theoretic in-feed amount through which the truing tool has to have been in-fed from its original position when the grinding wheel is worn down to a predetermined limit. Further, the circuit arrangement calculates an actual in-feed amount of the truing tool and by comparing the actual in-feed amount with the compensated theoretical in-feed amount, judges whether or not the grinding wheel has been worn down to a predetermined limit.

Abstract: A feed safety apparatus for a movable member slidably supported on a stationary bed of a machine tool. A feed device moves the movable member at various speeds. A hydraulic cylinder is fixedly mounted on the movable member and includes a piston slidably received therein. A reference plate member is secured to the bed and operatively connected to the piston for permitting bodily movement of the hydraulic cylinder and the piston within a predetermined distance, but restraining movement of the piston beyond the predetermined distance to cause relative movement between the hydraulic cylinder and the piston. A fluid flow regulating device is disposed between the pair of cylinder chambers of the hydraulic cylinder for restrictively controlling relative movement between the hydraulic cylinder and the piston.

Abstract: A feed control apparatus wherein a servomotor control device responsive to feed pulses distributed from a numerical controller controls a d.c. servomotor to advance a grinding wheel carriage of a grinding machine through the rotation of a feed screw successsively at a speed-up feed rate, a rapid feed rate, a slow-down feed rate and a grinding feed rate. A detection device is provided, which outputs a velocity checking signal to an abnormality confirmation device when the carriage reaches a velocity checking point defined within a slow-down feed range. When confirming that the feed rate of the carriage has exceeded a reference feed rate lower than the rapid feed rate, the abnormality confirmation device applies a stop signal to an emergency stop control circuit in response to the velocity checking signal, so that the rotation of the servomotor is immediately discontinued.