Abstract: An externally toothed portion of a cup-shaped flexible externally toothed gear of a wave gear device is flexed into an ellipsoidal shape by a six-roller-type wave generator. A region of an inner peripheral surface of the ellipsoidally flexed externally toothed portion that is positioned on a major axis of the ellipsoidal shape is maximally inclined. First rollers of the wave generator are arranged so that the incline is identical to the incline of the region of the inner peripheral surface. A circular outer peripheral surface of the first rollers can be brought into contact with the region of the inner peripheral surface in an external-tooth tooth-trace direction without deflection; therefore, the angular transmission precision of the wave gear device can be improved.

Abstract: The strain wave gearing includes a rigid internally toothed gear, a flexible externally toothed gear that is disposed coaxially therein and is flexible in the radial direction, and a wave generator that is disposed coaxially inside the externally toothed gear. The flexible externally toothed gear is bent in the radial direction by the wave generator and meshes with the rigid internally toothed gear in sections. When the position of meshing of the rigid internally toothed gear with the flexible externally toothed gear moves in the circumferential direction as the wave generator rotates, a relative rotation that corresponds to the difference in number of teeth of the two gears is generated between the two gears. A vibration-powered generator is disposed on the flexible externally toothed gear. The vibration-powered generator is provided with a piezoelectric element.

Abstract: A positioning control system for an actuator provided with a strain wave gearing is provided with: a semi-closed feedback controller FB(s) that controls a load shaft position ?l on the basis of a feedback motor shaft position ?m; and a feedforward linearization compensator configured by incorporating a nonlinear plant model for an object to be controlled into a feedback linearization compensator using an exact linearization technique. The feedforward linearization compensator uses a forward-calculated state quantity estimated value x* to calculate a feedforward current instruction i*ref and a feedforward motor position instruction ?*m to be input into the feedback controller FB(s). A positioning error caused by a non-linear element (non-linear spring property, relative rotational synchronization component, and non-linear friction) of the strain wave gearing is compensated for by the feedforward linearization compensator.

Abstract: Disclosed is a wave gear device (1) for setting the flexible state of the principal section (30) of a flexible external gear in a normal-deflection state (at a deflection coefficient ?=1). The moving locus of a tooth profile in the principal section (30) is determined by a rack approximation, and a similar curve (BC), which is obtained by similarly transforming a curve (AB) cut from that moving locus, is used to define the fundamental addendum shape of the tooth profile in the principal section.

Abstract: A visible laser beam scanned by a galvano-scanner system is aligned at each of positioning points on the top surface of a master work by manual operation to record sensor position signals of position sensors on galvano-scanners. The sensor position signals on each positioning point are recorded to create a drive pattern in accordance with recorded sensor position signals. The drive pattern no longer has optics system error sources including focus error and attachment error as well as errors caused by scale, offset and the like, also eliminating the need for entering a distance as far as the top surface of the work. Therefore, the drive pattern with error components removed can be created with ease.

Abstract: The flexible bearing of the wave generator for a wave gear device is a deep-groove ball bearing in which an outer race and an inner race form an annular flexible bearing ring capable of bending in a radial direction. A ball diameter Da is set to be 5 to 15% greater than that of each model of the currently available product. Dimensions of orbital plane radii ro, ri of the inner and outer races are set so that the ratio ro/Da of the orbital plane radius ro of the inner race and the ball diameter Da, as well as the ratio ri/Da of the orbital plane radius ri of the outer race and the ball diameter Da, are both in the range of 0.51 to 0.52. With this configuration, the service life of the flexible bearing can be extended.

Abstract: A cup-shaped flexible externally toothed gear of a wave gear device, wherein a diaphragm plate slopes from a diaphragm internal peripheral edge portion contiguous to a boss part toward a diaphragm external peripheral edge portion contiguous to a cylindrical body portion in a direction in which the diaphragm external peripheral edge portion is at greater distance from an open end of the cylindrical body portion with respect to an orthogonal plane orthogonal to a central axis line of the device. The length dimension of the diaphragm plate and the length dimension of the cylindrical body portion in the axial direction can be increased. Therefore, the fatigue strength of the diaphragm plate and the load capacity of the wave gear device in which the flexible externally toothed gear has been incorporated can be increased.

Abstract: A wave gear unit has an input shaft positioned along a center axis by first and second input bearings. A first unit end plate at the first-input-bearing side is a composite member in which a bearing housing member of an iron-based material is integrated with an end plate main body member of a lightweight material. A second unit end plate at the second-input-bearing side is integrated with a rigid internally toothed gear, and is a composite member in which a second member of a lightweight material is integrated with a first member of a lightweight material. The first member has an end plate main body portion of the second unit end plate and a gear main body portion of the rigid internally toothed gear, while the second member has a bearing housing portion of the second unit end plate and a teeth formation portion of the rigid internally toothed gear.

Abstract: In a wave gear device (1), radial deflection of a flexible external gear (3) is set at 2?mn (?>1) which is larger than a normal deflection of 2nm (?=1), and the tooth depth of both gears (2, 3) is set larger than a standard tooth depth (in case of ?=1). Meshing movement locus of both gears (2, 3) is approximated by a rack in case of ?>1, and using similarity-transformation curves (AC, AD) obtained by similarly enlarging a curve (AB) on the unmeshing side at the post-stage of meshing from the vertex (deepest meshing position)(A) of the movement locus (M), the dedendum tooth profile portion (21) of a rigid internal gear (2) and the addendum tooth profile portion (31) of the flexible external gear (3) are defined and then both gears (2, 3) are brought into continuous contact.

Abstract: In a wave gear device, similarity curve tooth profiles for defining the tooth-face tooth profile of each of a flexible externally toothed gear and a rigid internally toothed gear is determined from the movement trajectory, relative to a tooth of the rigid internally toothed gear, of a tooth of the flexible externally toothed gear at a main cross-section at which the deflection factor is ?=1. Tooth profile curves, which have been subjected to profile shifting corresponding to the difference between the deflection factor ?o (>1) of the opening-end cross-section of the flexible externally toothed gear and the deflection factor ? of the main cross-section, are determined from the similarity curves; and the tooth profile curves are used to form the tooth-face tooth profile portions of the two gears.

Abstract: Disclosed is a wave-type linear motion mechanism including a hydraulic pressure chamber for applying a retention force in the axial direction to a rigid screw member which moves in a linear fashion. Regulating valves are provided in the hydraulic pressure chamber, and these regulating valves open during the rotation of a wave generator so that no hydraulic pressure is exerted on the rigid screw member which moves in a linear fashion. During the rotation of the wave generator the regulating valves close to establish an airtight state in the hydraulic pressure chamber, and a hydraulic pressure is exerted as a retention force on the rigid screw member. Although restricted by the meshing strength between the rigid screw member and a flexible screw member and the buckling strength of the flexible screw member, the retention force of the wave-type linear motion mechanism is able to be increased.

Abstract: In a flexspline of a wave gear device, an annular flange thereof is constructed from a first annular part bent at a right angle from an outer peripheral edge of a diaphragm, and a second annular part caused to inwardly protrude at a uniform width from a leading end of the first annular part. It is possible for the annular flange to be disposed within the region where the diaphragm is formed, as viewed in the direction of an axis of the device. An outer diameter can be reduced to a greater extent than with a “silk hat”-shaped flexspline; and when a hollow wave gear device is manufactured, a hollow diameter can be more readily increased than in a case where a cup-shaped flexspline is used.

Abstract: In a hollow wave gear device, a rigid internally toothed gear and a wave generator are disposed adjacent along a center axis line so as to enclose a cylindrical barrel part of a flexible externally toothed gear from the outside. A pushed cylindrical portion adjacent to an external-tooth-formed cylindrical portion of the cylindrical barrel part is pushed from the outside and made to flex into an ellipsoidal shape by the wave generator disposed on the outside thereof, whereby external teeth partially mesh with internal teeth of the rigid internally toothed gear. The inside diameter dimension of a hollow part can be the inside diameter of the cylindrical barrel part of the flexible externally toothed gear, and a hollow wave gear device can be achieved which is formed with a hollow part having a large inside diameter.

Abstract: A cup-shaped flexible externally toothed gear of a wave gear device comprises a cylindrical body part, and an external-teeth area thereof includes a pushed portion pushed radially outward by a wave generator and a groove formed in a position adjacent to the pushed portion toward a diaphragm. The reaction force of the wave generator can be reduced because the groove is formed to partially reduce thickness in a portion that does not affect the root strength of the external teeth. The increase in root stress can be suppressed when the roots of the external teeth are thickened, and root strength can be effectively increased. The load torque of the wave gear device can thereby be increased.

Abstract: A wave generator for a wave gear device is provided with a pair of first rollers arranged in a position that is point-symmetric in relation to the center of a flexible externally toothed gear, a pair of second rollers, and a pair of third rollers. The first rollers are located on a long axis of the flexible externally toothed gear that is being flex into an ellipsoidal shape, and the second and third rollers are located in positions that are linearly symmetric in relation to the long axis between the long axis and a short axis. Support bearings of the first rollers are larger than those of the second and third rollers. The rolling fatigue life of a roller-type of the wave generator can be to be enhanced.

Abstract: In a flat wave gear device, there is determined a rack-approximated movement locus Lc1 of a flexible externally toothed gear with respect to an S-side rigid internally toothed gear accompanying rotation of a wave generator. ?OPT is a minimum value of the radius of curvature of the movement locus Lc1, and is determined from an evolute e of the movement locus Lc1. A convex arc having a radius ? (???OPT) is used in a main part of a tooth profile of the flexible externally toothed gear. A parallel curve c that is set apart from a movement locus Lc2 by the arc radius ? is used on a main part of a tooth profile to be generated on the S-side rigid internally toothed gear. The movement locus Lc2 accounts for the actual number of teeth, and is obtained from a center A of a convex arc of the flexible externally toothed gear being drawn with respect to the rigid internally toothed gear.

Abstract: A complex sensor comprises a touch sensor and a proximity sensor. The touch sensor comprises a flexible pressure-sensitive sheet covering a fingertip portion. The pressure-sensitive sheet comprises a front surface film and a rear surface film composed of a flexible conductive material, an intermediate film which is sandwiched between the films in a state in which the intermediate film is electrically connected and which is composed of pressure-sensitive conductive rubber, and first to fourth electrode terminals formed on the front surface and rear surface films. The size of a load acting on the pressure-sensitive sheet and the center position of the load can be detected based on the terminal voltage. A through-hole is formed in the pressure-sensitive sheet such that the sensing surface of the proximity sensor is exposed, thus the approach of a holding object can be detected.

Abstract: In a composite wave gear drive, a flexspline (having a number of teeth Nf) is disposed on the inner side of first and second circular splines (numbers of teeth Nc1 and Nc2, respectively). One side of the flexspline is bent into an elliptical shape by a first wave generator, the other side of the flexspline is bent into an elliptical shape by a second wave generator, and the flexspline meshes with the first and second circular splines. The first wave generator is a rotational input component, the second wave generator is a reduced-speed rotational output component, and the first and second circular splines are kept from rotating. The number of teeth is set such that Nc2=Nc1+2 and Nc1=Nf+2. A backlash-free gear drive having a low reduction ratio can be obtained.

Abstract: According to a method for performing adaptive friction compensation of an actuator including a wave gear drive, there is used as a friction compensation current applied to a motor drive current a static friction compensation current is when a motor shaft stops with a deviation, and a Coulomb friction compensation current ic in other circumstances. The static friction compensation current is is obtained by adding a compensation amount isr of a monotonically increasing ramp function to a compensation amount iss of a step function, and a step-function compensation amount ics is used as the Coulomb friction compensation current ic. Since the amount of friction compensation can be changed adaptively based on the data during positioning-control response, a motor shaft can be stabilized at a target angle without prominent accompanying vibration, even if the ambient temperature changes and the friction characteristics of the wave gear drive fluctuate.

Abstract: In a wave linear motion mechanism (4) of a holding mechanism (1), those portions of a flexible screw (14) where first and second male screws (32, 33) are formed are elliptically deformed by first and second wave generators (12, 13) installed on an input shaft (11), and the first and second male screws (32, 33) are respectively partially engaged with first and second female screws (42, 44) of first and second circular nuts (15, 16). First and second holding members (5, 6) are mounted on the first and second circular nuts (15, 16), respectively. When the input shaft (11) is rotated by a motor (3), the first and second holding members (5, 6) are opened or closed depending on the rotation direction to release or hold an object (W).