Measuring and testing – Speed – velocity – or acceleration – Angular rate using gyroscopic or coriolis effect
Reexamination Certificate
1999-12-30
2001-10-16
Kwok, Helen (Department: 2856)
Measuring and testing
Speed, velocity, or acceleration
Angular rate using gyroscopic or coriolis effect
C073S504020
Reexamination Certificate
active
06301963
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to a microgyroscope in which an oscillating mass is oscillated by dividing it into three parts, and the three oppositely oscillating mass parts are made to be equal to each other, so that the forces transmitted from external oscillations are minimized, thereby minimizing the influence of the external oscillations.
BACKGROUND OF THE INVENTION
Generally, the angular velocity sensing devices for detecting the angular velocities of inertial bodies have been widely employed as a component of navigation apparatus in the ocean vessels, air planes and the like. At the present, this device has been extended to the navigation apparatus of automobiles, and to the high performance video camera as a hand-oscillation compensating device.
The conventional gyroscope which has been used for the military purposes and for air planes is manufactured by using a plurality of high precision components and through a complicated assembling process, and therefore, a precise performance is possible. However, its manufacturing cost is high, and its bulk is very large, with the result that it cannot be used for the general industries, and for the home power appliances.
Recently, a small gyroscope has been developed by attaching a piezoelectric device to a triangular prism beam, and this is used as a hand-oscillation sensor for a small video camera. Further, in order to overcome the difficulties of the gyroscope having the piezoelectric device, a small gyroscope with an improved cylindrical beam structure has been developed.
However, these two kinds of the small gyroscopes require precisely machined components, and therefore, the manufacture becomes difficult, while the manufacturing cost becomes high. Further, the mentioned two kinds of gyroscope includes a plurality of mechanical components, and therefore, it is difficult to form a circuit integration.
The principle of the gyroscope is as follows. That is, when a rotating inertial body which rotates or oscillates in a first axis direction receives an input of an angular velocity in a second axis direction (which is perpendicular to the first axis direction), the gyroscope detects a Coriolis force which acts in a third axis direction (which is rectangular to the first and second axes direction).
Under this condition, if the forces acting on the inertial body are made to be balanced, then the detection of the angular velocity has to be more precise. Particularly, if the linearity and the band width are to be expanded, a force balancing structure is required.
A conventional microgyroscope related to this technique is illustrated in U.S. Pat. No. 5,747,690, and it is as shown in FIG.
1
.
As shown in
FIG. 1
, an excitation is made to occur in the horizontal direction by utilizing combs
41
, and in the same manner, the Coriolis oscillations of a floating mass
50
induced in the perpendicular direction (y axis) can be sensed by sensing electrodes
38
.
Under this condition, in the case where an ac voltage is supplied to combs
39
,
40
,
41
and
42
of both sides of the floating mass
50
so as to make the floating mass
50
oscillate in the direction of the x axis, if an angular velocity is inputted in the direction of the z axis, then the mass is oscillated in the direction of the y axis with the same frequency by the Coriolis force. Under this condition, the oscillation range in the direction of the y axis can be detected based on the relevant oscillation frequency by utilizing the sensing electrodes
38
proportionally to the supplied angular velocity, thereby obtaining the angular velocity signals.
However, in the above described case, the mass oscillates to one side, and therefore, the oscillations are excessively transmitted to the supporting part. As a result, a mechanical loss is resulted, and the exciting oscillation width is affected by the external oscillations.
Further, in the above described microgyroscope, by the strong transmission of the oscillations to the supporting part
31
, a negative influence is received to the rise of the sensitivity of the gyroscope, and the linearity is aggravated due to the magnitude of the angular velocity. Consequently, the resolving power of the gyroscope is lowered, and the life expectancy of the gyroscope is shortened.
SUMMARY OF THE INVENTION
The present invention is intended to overcome the above described disadvantages of the conventional techniques.
Therefore it is an object of the present invention to provide a microgyroscope in which an oscillating mass is oscillated by dividing it into three parts, and the three oppositely oscillating mass parts are made to be equal to each other, so that the forces transmitted from external oscillations are minimized, that the influence of the external oscillations is minimized, and that the friction loss of the supporting parts is minimized, thereby improving the resolving power of the gyroscope, and extending the life expectancy of the gyroscope.
In achieving the above object, the microgyroscope according to the present invention includes: an inner frame as an inner mass part excitedly installed within an outer frame to be unitizingly excited together; a first plurality of combs installed laterally and in a y axis direction at both sides of the inner frame and within the inner frame; perpendicular direction sensing electrodes disposed between the first plurality of the combs at certain intervals, and supported by electrode supporting parts; outer mass parts installed at both sides of the inner mass part; elastic bodies excitedly installed between the outer frame and the outer mass parts; oscillation structures extending in a lateral direction of the outer mass parts; a second plurality of combs installed at a side of each of the oscillation structures; exciting drivers for causing excitations by supplying a voltage; and a third plurality of combs disposed respectively between the second plurality of the combs of the oscillation structures, for detecting the excitations from a difference of capacitances between the exciting drivers.
REFERENCES:
patent: 5728936 (1998-03-01), Lutz
patent: 5747690 (1998-05-01), Park et al.
patent: 6067858 (2000-05-01), Clark et al.
patent: 6089088 (2000-07-01), Charvet
patent: 6089089 (2000-07-01), Hsu
patent: 6122961 (2000-09-01), Geen et al.
patent: 6134961 (2000-10-01), Touge et al.
Kwok Helen
Lowe Hauptman & Gilman & Berner LLP
Samsung Electro-Mechanics Co., LTD
LandOfFree
Microgyroscope having inner and outer mass parts does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Microgyroscope having inner and outer mass parts, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Microgyroscope having inner and outer mass parts will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2591568