Kabushiki Kaisha Suwa Seikosha

Seiko Epson Corporation

Epson Corporation

Yoshikazu Kawamura

Sakiho Okazaki

Minoru Hosokawa

Hiroshi Ishii

Akio Shimoi

Kenichi Koike

Hiroshi Eguchi

Yuichiro Iwai

A step motor driving control mechanism for use in an electronic timepiece for reducing the current consumption thereof is provided. Load detection circuitry detects the load condition of the step motor and selectively produces a load condition signal representative of a predetermined load condition thereof. Driving and control circuitry is provided for receiving a low frequency timekeeping signal produced by a divider circuit and a load detection signal when same is selectively produced by the load detection circuitry. In response to the presence or absence of a load detection signal applied thereto, the drive and control circuitry is adapted to vary the duration of the pulse width of a drive signal applied to the step motor to effect a driving of same.

Step motor control mechanism for electronic timepiece

An ink jet recording apparatus for projecting ink onto a recording medium. The apparatus includes an ink jet head adapted to receive ink having an ejection nozzle for ejecting ink towards said recording medium. An ink tank means stores ink and supplies the stored ink to the ink jet head. A switching mechanism selectively switches between a first condition where the ink tank is in fluid communication with the ink jet head and a second condition where the ink jet head is vented to atmosphere. A nozzle cap selectively covers the ejection nozzle. A suction mechanism creates a suction in the cap. The cap draws ink and air out of the ink jet head through the ejection nozzle to prevent clogging and remove air bubbles from the ink.

Ink jet recording apparatus

An improved electronic timepiece transducer wherein the construction of the permanent magnet rotor and a magnetic permeable stator effects a reduction in energy consumption during operation. In particular, the rotor is characterized by a predetermined thickness and at least two concentric circular equal radii surfaces having the same radius. Similarly, the stator includes highly permeable stator poles having a predetermined thickness and two symmetrical equal radii semi-circular stator surfaces having the same radius and surrounding the rotor. The ratio of the rotor radii to the stator radii and the ratio of the rotor thickness to the stator thickness define a specific relationship that effects a reduction in the energy consumed by the step motor during operation.

Transducer for electronic timepiece

A step motor driving circuit for selectively effecting a rotational stepping of a rotor in a forward rotational direction or in a reverse rotational direction is provided. The driving circuit is coupled to the drive coil of a motor and is disposable into a first mode for applying, to the drive coil, a first drive signal for effecting a periodic rotation of the rotor in a first rotational direction. The drive circuit is further disposable into a second mode for applying to the drive coil a second drive signal for effecting a periodic rotation of the rotor in the opposite rotational direction. A mode select circuit is coupled to the drive circuit and is adapted to dispose the drive circuit into either a first or second mode to thereby select the direction of rotation of the rotor.

Step motor driving circuit

A step motor driving control mechanism for use in an electronic timepiece for reducing the current consumption thereof is provided. Load detection circuitry detects the load condition of the step motor and selectively produces a load condition signal representative of a predetermined load condition thereof. Driving and control circuitry is provided for receiving a low-frequency timekeeping signal produced by a divider circuit and a load detection signal when same is selectively produced by the load detection circuitry. In response to the presence or absence of a load detection signal applied thereto, the drive and control circuitry is adapted to vary the duration of the pulse width of a drive signal applied to the step motor to effect a driving of same.

A step motor driving and control mechanism for use in an electronic timepiece for reducing the current consumption thereof is provided. Load detection circuitry detects the load condition of the step motor by detecting the signals induced in the drive coil of the step motor after each stepping of the rotor. The load detection circuitry selectively produces a load condition signal in response to detecting current peaks representative of a predetermined load condition of the step motor. The load detection circuitry is characterized by the use of MOS transistors therein for accurately detecting the occurrence of the current peaks. Driving and control circuitry is provided for receiving a low frequency timekeeping signal produced by a divider circuit and a load detection signal, when same is selectively produced by the load detection circuitry. In response to the presence or absence of a load detection signal applied thereto, the drive and control circuitry is adapted to vary the duration of the pulse width of a drive signal applied to the step motor to effect a driving of same.

A touch sensitive input particularly suited for use with an electronic wristwatch, an electronic calculator or a combination thereof is provided. The touch sensitive input includes a touch sensitive contact connected to the input of a detector circuit, the detector circuit input being normally referenced to a first potential for producing a detector circuit output signal representative of the first potential. Engagement of the touch sensitive contact selectively references the detector circuit input to a second potential and in response thereto produces a detector circuit output signal representative of the second potential. The detector circuit includes at least an MOS or C-MOS input stage. Additional circuitry is provided for eliminating chatter in the output signal produced by the input stage, for preventing the producing of two signals representative of the unintended engagement of more than one touch sensitive contact, and for providing an indication that a touch sensitive contact has been inadvertently engaged.

Touch sensitive input for electronic wristwatch and/or electronic

A step motor having a rotor adapted to rotate a full revolution in response to each pulse applied to the stator is provided. Positioning magnets are provided for positioning a rotor in a rest position and a stator is positioned around the rotor to overcome the magnetic field of the positioning magnets upon the application of a pulse to the stator to thereby effect a complete revolution of the rotor.

Step motor

An electronic wristwatch having calculator circuitry operated by the time standard signals utilized to operate the timekeeping circuitry is provided. The electronic wristwatch includes a timing pulse generating circuit for producing a plurality of signals. Timekeeping circuitry is coupled to the timing pulse time standard signals produced thereby, for producing a plurality of timekeeping signals representive of actual time in response to at least one of the time standard signals being applied thereto. A digital display is provided for displaying actual time in response to at least some of the plurality of timekeeping signals being applied thereto. Calculator circuitry is provided for producing calculation signals representative of numerical information or a calculating function in response to receiving at least two of the time standard signals produced by the timing pulse generator means, the digital display being adapted to display the numerical information and calculating function in response to the calculating signals produced by the calculating circuitry being applied thereto.

Electronic wristwatch

In a motor having a rotor which is a permanent magnet, the rotor is in the form of a cylinder from which portions have been cut forming surfaces symmetrical with respect to the axis of the cylinder. The moment of inertia of the rotor is thereby reduced so that response to a magnetic impulse is more rapid. Further, the plane of magnetism is asymmetric with respect to the plane bisecting the cylindrical surfaces of the rotor, thereby providing for greater thrust under the effect of the yoke and increasing the efficacy of said motor for stepping purposes.

Stepping motor

A rotary motion transformer particularly adapted to provide continuous rotary motion to a driven member in response to an intermittently rotated driving member is provided. The driven member and the driving member are oppositely poled magnetic permeable members disposed proximate to each other to provide a flux field therebetween. The driven rotary member is disposed in a viscous damping reservoir, the viscous damping reservoir effecting smooth and continuous rotation of the driven member.

Growing community of inventors

Suwa, Japan

Yoshikazu Kawamura