Harmonic Drive Systems Inc.

Nozomu Tanioka

Jun Handa

Akira Akahane

Toshiki Maruyama

Kunio Miyashita

Syuhei Kobayashi

Kazumasa Furuta

In a strain wave gearing, both of a pulley for transmitting rotation in a direction orthogonal to a rotation central axis and an output shaft are arranged on an axial-direction first side relative to a cup-shaped externally toothed gear. The input shaft, which transmits input rotation from the pulley to the wave generator, functions as a support shaft for both the pulley and the wave generator and is supported at both ends by the first and second bearings. A mechanism for transmitting rotation from the pulley to the wave generator, and a mechanism for supporting the rotation-transmitting mechanism, can be made compact, and support strength can also be ensured.

Strain wave gearing

A strain wave gearing has three components and a temporary-fixing jig, three components being an internally toothed gear, a cup-shaped externally toothed gear, and a wave generator. The temporary-fixing jig is securely fastened to an output shaft fixed to the externally toothed gear by a temporary-fixing bolt and is securely fastened to an input shaft fixed to a cam plate of the wave generator by a temporary-fixing bolt. The temporary-fixing jig engages with the output shaft and the input shaft and maintains the three components in an assembled state. There is no need for an operation for adjusting the positions of the three components in an operation for attaching the strain wave gearing to a motor. After the strain wave gearing has been attached to the motor, the temporary-fixing jig is removed from the strain wave gearing, wherefore less space is required for installation.

In a magnetic drive linear actuator, a load attachment portion is fixed to the lower side portion of the rectangular tubular coil frame of a mover, and a light-emitting portion of a position detection portion for detecting the movement position of the mover is fixed to the upper side portion of the coil frame. The load attachment portion and the upper side portion of the coil frame are mutually coupled through beam portions bridged there between. This makes it possible to prevent or suppress the behaviors of the load attachment portion and light-emitting portion from being shifted to each other during high-acceleration driving of the mover, thereby improving the responsiveness and positioning accuracy of the linear actuator.

Linear actuator

A rotary actuator equipped with a sensing mechanism includes a motor and a reducer concentrically disposed inside a cylindrical housing; a scale for detecting the rotational position of a rotary arm, the scale being disposed on the circular outer face of the cylindrical housing; and a position sensor mounted in the facing section of the rotary arm that rotates along the circular outer face, the facing section being in a facing arrangement with the circular outer face. A detection mechanism includes the scale and the position sensor detects the rotational position of the rotary arm capable of rotating within a finite angular range along the circular outer face of the cylindrical housing. The components are concentrically disposed. The actuator is suitable for use as a digital joint unit.

Rotary actuator equipped with sensing mechanism, and joint unit

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.

Method for creating drive pattern for galvano-scanner system

In a galvano scanner system (), a light position detection unit () is mounted so as to match the scanning center of the workpiece surface (), the light position detection unit being provided with a two-dimensional light position sensor () disposed in the center and four one-dimensional light position sensors (()) to (()) concyclically disposed at equal angles about the center of the two-dimensional light position sensor. An origin position command is given to galvano scanners (), laser light is irradiated at low output, and the offset adjustment value is calculated based on the detection output of the two-dimensional light position sensor (). Next, the galvano scanners () are pivoted left, right, up, and down; the perpendicularity in relation to the workpiece surface () is determined and the distance from the workpiece surface () is calculated based on the detection output of each one-dimensional light position sensor (); and the scale adjustment value is calculated on the basis thereof. Adjustment can be carried out with good accuracy in a simple manner in comparison with the case in which such an adjustment is made in alignment with a scale on a workpiece surface while visually observing visible laser light.

Method for adjusting galvano scanner system

A scanner driver of a galvanometric scanner system includes an analog drive circuit; a control unitfor storing and holding optimized data formed from combinations of optimal values of circuit constants set in advance in accordance with a plurality of drive modes of a galvanometric scanner; and an electronic trimmer for changing the circuit constants of the analog drive circuit. The control unit selects one of the optimized data in accordance with an external input, and sets or updates parameters of the circuit constants via the electronic trimmer in accordance with the selected optimized data. When a drive mode of the galvanometric scanner system is changed, the scanner driver can accordingly be optimized readily and quickly.

Method for adjusting drive characteristics of scanner driver of galvanometric scanner

A galvano-scanner system () has a position-controlling microcomputer () mounted on a scanner driver () of a galvano scanner (), wherein a position detection signals outputted from a positional sensor () of the galvano-scanner () are sampled, the current position of the galvano-scanner () is updated on the basis of sampling results, when movement distance amount command data are input, the movement distance amount command data are converted to an address change amount for the galvano-scanner (), the address change amount is added to the current position to obtain a movement destination address. The movement destination address is converted to an analog position command and supplied to a drive circuit (). The drive circuit () generates position command voltage corresponding to the analog position command and causes to move the galvano scanner () by that movement distance. The galvano-scanner () can be controlled in a simple manner to move from a current position to an arbitrary position.

Drive control method for galvano-scanner

In a linear actuator (), on the inside of a rectangular tubular movable element (), a linear guide () that supports the movable element () so as to be linearly movable is positioned at a center of the movable element (), and a position detecting mechanism () and load attaching member () that sandwich the linear guide are disposed linearly in a vertical direction. This arrangement enables a center of gravity of the movable element () to be matched with a center of the linear guide (). A magnetic circuit is in a bilaterally symmetrical relationship with regard to the center of the movable element (). Therefore, a center of a thrust force that acts upon the movable element () is matched with the center of the movable element (). The center of the thrust force that acts upon the movable element (), the center of gravity of the movable element (), and the center of the linear guide () are positioned at the center of the movable element (). Resistance to sliding in the movable element () can be reduced without unreasonable stress being placing on the linear guide (). Therefore, a magnetically driven linear actuator that has highly precise positioning and that is durable can be realized.

A galvano scanner system has a galvano scanner and a scanner driver for driving the scanner, wherein a microcomputer for generating commands in which digital data representing a drive pattern of the scanner is written is mounted in the scanner driver. The microcomputer for generating commands is actuated by an external or internal trigger signal, and the digital data of the drive pattern is sequentially output. The output data is converted to an analog signal in a DA converter, and a drive control circuit generates a drive signal of the scanner on the basis of the analog signal to drive the galvano scanner. A system that can optimally drive a galvano scanner can be achieved with a small inexpensive system configuration.

Driving method for galvano scanner

A DC motor of a galvanometer-type scanner has four poles, and compared to a conventional DC motor with a bipolar construction, the armature inductance L can be reduced to half or less for a case where the external diameter of the rotor and the induced voltage constant K are the same. Since K /L, which is the index for the rise of torque of the motor, is increased by a factor of two or more, the responsiveness of the motor can be improved without increasing the exciting current of the winding. Accordingly, it is possible to provide a galvanometer-type scanner that can set minute angles of around one degree within several hundred microseconds.

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Azumino, Japan

Nozomu Tanioka