Drive unit for a rotary decoration
First Claim
1. A drive unit for a rotary decoration comprising:
- a stepping motor capable of rotating in both forward and reverse directions in response to drive pulses applied thereto for reciprocally driving a rotary decoration through a predefined angular displacement;
a memory circuit for storing drive timing data for said stepping motor; and
a control circuit for controlling said stepping motor on the basis of the data stored in said memory circuit;
said data comprises numeralized values representing pulse intervals between the drive pulses of said stepping motor so that the rotational speed of said rotary decoration can vary in conformity with a sine curve; and
said pulse intervals occurring in a predetermined middle region defined about a midpoint of a unidirectional angular displacement rotation of said rotary decoration and being equally spaced in time relation and smaller than pulse intervals occurring in other regions of the angular displacement.
2 Assignments
0 Petitions
Accused Products
Abstract
A drive unit for a rotary decoration has a transmission gear train configured to include a damper such as a coil spring and is capable of imparting a visually elegant swing motion to the rotary decoration. A reciprocating stepping motor is capable of rotating or turning in both the forward and reverse directions to drive a rotary decoration in such a manner that the rotary decoration exhibits a reciprocative swing motion over a specified angular displacement. A memory circuit stores data for determining the drive timing of the stepping motor. A control circuit controls the stepping motor in accordance with the data stored in the memory circuit. The data represents the interval between drive pulses supplied to the stepping motor so as to cause the rotational speed of the rotary decoration to vary according to a sine curve. In alternative embodiments, (1) the intervals between drive pulses are set to a uniform and short value in a predetermined region of the specified angular displacement; (2) the intervals between drive pulses are set to a short value in a predetermined region of the specified angular displacement which corresponds to the location immediately after which the rotational direction of the rotary decoration is reversed; and (3) the drive pulses are blanked over a predetermined region corresponding to the location immediately before the rotational direction of the rotary decoration is reversed.
7 Citations
18 Claims
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1. A drive unit for a rotary decoration comprising:
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a stepping motor capable of rotating in both forward and reverse directions in response to drive pulses applied thereto for reciprocally driving a rotary decoration through a predefined angular displacement; a memory circuit for storing drive timing data for said stepping motor; and a control circuit for controlling said stepping motor on the basis of the data stored in said memory circuit; said data comprises numeralized values representing pulse intervals between the drive pulses of said stepping motor so that the rotational speed of said rotary decoration can vary in conformity with a sine curve; and said pulse intervals occurring in a predetermined middle region defined about a midpoint of a unidirectional angular displacement rotation of said rotary decoration and being equally spaced in time relation and smaller than pulse intervals occurring in other regions of the angular displacement.
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2. A drive unit for a rotary decoration comprising:
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a stepping motor capable of rotating in both forward and reverse directions in response to drive pulses applied thereto for reciprocally driving a rotary decoration through a predefined angular displacement; a memory circuit for storing drive timing data for said stepping motor; and a control circuit for controlling said stepping motor on the basis of the data stored in said memory circuit; said data comprises numeralized values representing pulse intervals between the drive pulses of said stepping motor so that the rotational speed of said rotary decoration can vary in conformity with a sine curve; and said pulse intervals occurring in a predetermined region immediately after changing the rotational direction of said rotary decoration and being smaller than other pulse intervals occurring in other regions of the angular displacement.
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3. A drive unit for a rotary decoration comprising:
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a stepping motor capable of rotating in both forward and reverse directions in response to drive pulses applied thereto for reciprocally driving a rotary decoration through a predefined angular displacement; a memory circuit for storing drive timing data for said stepping motor; and a control circuit for controlling said stepping motor on the basis of the data stored in said memory circuit; said data comprises numeralized values representing pulse intervals between the drive pulses of said stepping motor so that the rotational speed of said rotary decoration can vary in conformity with a sine curve; and said data providing a blank pulse region in which no drive pulses are applied to the stepping motor, the blank pulse region occurring in a predetermined region immediately before the rotational direction of said rotary decoration is changed.
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4. A drive unit for turning a member about its axis, comprising:
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turning means responsive to drive pulses applied thereto for turnably displacing a member about its axis through a predetermined angular displacement alternately in both forward and reverse directions; driving means for applying drive pulses separated by time intervals to the turning means to effect turning displacement thereof; storing means for storing timing data representative of durations of the time intervals between applications of drive pulses to the turning means; and controlling means for controlling the time intervals between drive pulses applied to the turning means on the basis of the timing data stored in the storing means to thereby cause the rotational speed of the turning means to vary in conformity with a sine curve. - View Dependent Claims (5, 6, 7, 8, 9, 10, 11, 12)
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13. A drive unit for turning a member, comprising:
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turning means for applying a turning force to a member to reciprocatively swing the member through a predetermined angular displacement, the predetermined angular displacement having a first endpoint, a middle portion and a second endpoint; driving means for driving the turning means so as to reciprocatively swing the member through the predetermined angular displacement; and controlling means for sequentially generating a series of drive pulses and applying the same to the driving means to effect driving of the turning means, wherein adjacent drive pulses are separated by respective time intervals having a duration, and wherein the series of drive pulses are applied so that drive pulses applied during a time at the middle portion of the predetermined angular displacement are separated by time intervals having an equal duration which is shorter than a duration of time intervals separating drive pulses applied during a time from an end of the middle portion to the first endpoint and during a time from another end of the middle portion to the second endpoint so that the member is turned to reciprocatively swing through the predetermined angular displacement at an angular speed varying in conformity with a sine curve. - View Dependent Claims (14, 15, 16, 17, 18)
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Specification