Abstract: In a cylindrical grinding machine, a lateral surrounding cover is mounted on a bed and surrounds and covers lateral surfaces of a machining area in which a work support drive device, a grinding wheel and a bearing unit therefor are arranged and a slide area in which a base portion of a wheel head and a slide mechanism for the wheel head are arranged. A top open/close cover is further provided on the top portion of the lateral surrounding cover and is movable between a first position to open the upsides of the machining area and the slide area and a second position to cover the upsides of the machining area and the slide area. Thus, only by moving the top open/close cover to the first position, it becomes possible for an operator to look over the whole part of the machining area and the slide area. Since plural components of the grinding machine can be checked simultaneously with the top open/close cover opened, the time taken for maintenance or service work on the grinding machine can be shortened.

Abstract: In a truing method and apparatus, an analyzing method is employed to calculate a truing shape from which a grinding surface having been trued with a grinding wheel being rotated at a low rotational speed during a truing operation is deformed to a desired shape due to centrifugal expansion depending on a rotational speed difference when the grinding wheel is rotated at a high rotational speed during a grinding operation. Then, with the grinding wheel being rotated at the low rotational speed, the grinding surface is trued with a truing roll to the calculated truing shape. As a result, the grinding surface of the grinding wheel being rotated at the low rotational speed is trued with the truing roll taking into consideration the centrifugal expansion of the grinding surface which takes place when the grinding wheel is rotatated at the high rotational speed during the grinding operation subsequent to the truing operation.

Abstract: In a cylindrical grinding machine, a lateral surrounding cover is mounted on a bed and surrounds and covers lateral surfaces of a machining area in which a work support drive device, a grinding wheel and a bearing unit therefor are arranged and a slide area in which a base portion of a wheel head and a slide mechanism for the wheel head are arranged. A top open/close cover is further provided on the top portion of the lateral surrounding cover and is movable between a first position to open the upsides of the machining area and the slide area and a second position to cover the upsides of the machining area and the slide area. Thus, only by moving the top open/close cover to the first position, it becomes possible for an operator to look over the whole part of the machining area and the slide area. Since plural components of the grinding machine can be checked simultaneously with the top open/close cover opened, the time taken for maintenance or service work on the grinding machine can be shortened.

Abstract: A linear motor actuated machine tool includes a bed, a column, upper and lower X-axis guides, a saddle, upper and lower X-axis linear motor magnets, and upper and lower X-axis linear motor coils. Upper and lower X-axis guides are attached to the upper and lower portion of front surface of the column, which is mounted on the bed in the vertical direction, in the horizontal direction. Upper and lower X-axis linear motor magnets is fixed on the front surface of the column at upper side and lower side of the upper and lower X-axis guides in the direction of X-axis with making pole surfaces thereof face to frontward. Upper and lower X-axis linear motor coils are fixed to upper end and lower end of the rear surface of the saddle, which is mounted on the front surface of the column with being guided by upper and lower X-axis guides and having a through space at the center portion thereof, with opposing to upper and lower X-axis linear motor.

Abstract: It is an object of the present invention to provide a wheel shaft supporting apparatus for a grinding machine achieving easy assembling and disassembling of a grinding wheel supported by a pair of wheel shafts and increasing centering accuracy of both wheel shafts and stiffness in combined wheel shaft.

Abstract: Disclosed is a cylindrical grinding machine of the type that a workpiece support device composed of a work head and a foot stock is mounted on a forward upper portion of a bed while a wheel head unit composed of a slide base and a wheel head is mounted on a rear upper portion of the bed. A coolant collecting vent which takes a rectangular shape as viewed from above vertically extends in the bed and opens to the upper surface of the bed to cover an area that extends from under the workpiece on the workpiece support device to under the forward portion of the wheel head unit. A horizontal vent is provided in the bed to open to the rear surface of the bed and to communicate with the collecting vent. A coolant supply device is inserted at a part thereof into the horizontal vent from the rear surface of the bed to extend an inlet opening into the collecting vent.

Abstract: A grinding head guiding apparatus is disclosed. The grinding head is driven by the linear motor which is constituted of a coil attached on an underside surface of the grinding head and a magnet attached on an upside surface. Horizontal guiding members are fixed on the base, and the grinding head is guided to the horizontal guide members. Then, a height of a portion opposing the coil and the magnet is approximately same as a height of the horizontal guide members guiding the grinding head. Besides, temporary supporting members are attached on the base so as to avoid sticking the coil to the magnet, when the coil is detached from the grinding head. Further, the grinding head has ribs therein, which define an approximately trapezoid-shaped space disposed a center of the grinding head and triangle-shaped spaces disposed both side of the trapezoid-shaped space.

Abstract: A grinding head guiding apparatus is disclosed. The grinding head is driven by the linear motor which is constituted of a coil attached on an underside surface of the grinding head and a magnet attached on an upside surface. Horizontal guiding members are fixed on the base, and the grinding head is guided to the horizontal guide members. Then, a height of a portion opposing the coil and the magnet is approximately same as a height of the horizontal guide members guiding the grinding head. Besides, temporary supporting members are attached on the base so as to avoid sticking the coil to the magnet, when the coil is detached from the grinding head. Further, the grinding head has ribs therein, which define an approximately trapezoid-shaped space disposed a center of the grinding head and triangle-shaped spaces disposed both side of the trapezoid-shaped space.

Abstract: A machine tool is structured enhance rigidity of a slide member opposing to a cutting force acting on a tool spindle with no extra increase in weight, thereby intending to lighten the slide member. The machine tool comprises a tool spindle rotating around an axis extending along an Z-axis, a slide member slidable in at least one of the X-axis, Y-axis and Z-axis directions and a guide apparatus having a straight rail and movably supporting the slide member on the guide rail and disposed such that three supporting points for supporting the slide member form vertexes of a triangle as seen from the X-axis direction. Further, in another construction, two sets of linear guide mechanism and a linear motor for guiding each of an upper portion and a lower portion of a gantry are respectively disposed between a lower surface of the gantry and a base, and between a front surface of a cross beam and an upper back surface of the gantry, so that the cross beam does not lap over the upper surface of the gantry.

Abstract: A method for detecting the coordinate position of the grinding point of a grinding wheel supported on a swiveling table comprises the steps of: rotating drivably the swiveling table through a specified angle from a start position so as to arrive at a first turning position; measuring a first displacement of the grinding point of the grinding wheel from the start position by displacement measuring means; rotating the swiveling table through the specified angle from the first turning position so as to arrive at a second turning position; measuring a second displacement of the grinding point of the griding wheel from the first turning position by the displacement measuring means; and calculating the position of the grinding wheel with respect to the swivel axis of swiveling table according to the first and the second displacement and the specified angle.

Abstract: A grinding machine for grinding outer and/or inner surfaces of a workpiece which is provided on its indexable wheel head with an outer surface grinding wheel, inner surface grinding wheel and a measuring device having a touch probe engagable with a reference surface of the workpiece. A numerical controller having a memory for memorizing data indicating positional and angular relationships between the outer surface grinding wheel, the inner surface grinding wheel and the touch probe is provided. The numerical controller first indexes the measuring device to a location facing the workpiece, and moves the workpiece along its rotational axis until the measuring device outputs a touch signal. After that, the numerical controller calculates a moving amount of the workpiece for an outer grinding operation based upon data memorized in the memory, and moves the table by the calculated amount in order to grind the outer surface of the workpiece.

Abstract: In a numerical control grinding machine using a grinding wheel made of cubic boron nitride, a computerized numerical controller controls the infeed movement of a wheel head to effect a rough grinding, a drifty grinding and a fine grinding on a rotating cylindrical workpiece. The drifty grinding due to a spring-back motion which is caused by a flexed workpiece is initiated in response to a sizing signal from a sizing device which measures the workpiece diameter varying momentarily during the grinding operation and is terminated upon the expiration of a predetermined time which is sufficient to vanish the variation of the workpiece diameter. A sizing device measures the actual diameter thereafter, and the sizing signal is compensated in order to approximate the actual diameter to a desired set size which is the sum of a finish diameter and a predetermined allowance for the subsequent fine grinding operation, as the number of the workpieces increases.