Coded data generation or conversion – Digital pattern reading type converter – Brush and contacts or conductive pattern
Reexamination Certificate
1999-06-30
2001-08-07
Tokar, Michael (Department: 2819)
Coded data generation or conversion
Digital pattern reading type converter
Brush and contacts or conductive pattern
Reexamination Certificate
active
06271770
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates a coder, and more particularly, to a mechanical coder.
2. Description of the Prior Art
Referring to 
FIG. 1
, which depicts a conventional obstructing type coder including an emitter 
10
, a receiver 
20
 and an optical shutter 
30
. The optical shutter 
30
 is made of opaque material. A plurality of rectangular openings 
31
 are formed on the periphery of the optical shutter 
30
. While the optical shutter 
30
 is rotating, the light emitted by the emitter 
10
 may pass through the openings 
31
 or be interdicted by the opaque optical shutter 
30
. As the light emitted from the emitter 
10
 passes through the openings 
31
, the receiver 
20
 accepts an “ON” signal. Conversely, as the light emitted from the emitter 
10
 is interdicted by the opaque optical shutter 
30
, the receiver 
20
 receives an “OFF” signal. Thus, a plurality of “ON” signals and a plurality of “OFF” signals constitute a continuous light-and-shade signal having constant interval. The light-and-shade signal is received and then transferred into a digital logic signal for output.
In order to increase the resolution, increasing the number of the shutter 
32
 is desired. However, the more the numbers of shutters 
32
, the more serious is the problem caused by scattering and diffraction. Scattering and diffraction will result in the difficulty in clarifying “ON” signal or “OFF” signal. Thus the receiver 
20
 to judge the received signal exactly. Hence it is difficult to increase the resolution without limits.
Referring to 
FIG. 2
, which depicts another conventional guidance type coder including an emitter 
10
, a receiver 
20
 and an optical shutter 
30
 made of transparent material. There are a plurality of gear-shaped projections 
33
 and a plurality of recesses 
34
 formed on the periphery of the optical shutter 
30
. Additionally, there are a plurality of refraction planes 
35
 formed on the inner portion of the optical shutter 
30
. While the optical shutter 
30
 is rotating, the light emitted by the emitter 
10
 may be refracted to projections 
33
 or recesses 
34
. As the light emitted by the emitter 
10
 is refracted to projections 
33
, the receiver 
20
 accepts an “ON” signal. Conversely, as the light emitted by the emitter 
10
 is refracted to recesses 
34
, the receiver 
20
 receives an “OFF” signal. Thus, a plurality of “ON” signals and a plurality of “OFF” signal constitute a continuous light-and-shade signal having a constant interval. The light-and-shade signal is received and then transferred into a digital logic signal for output.
The resolution of the guidance type coder is higher than that of the above-mentioned obstructing-type coder. However, the optical distance of the guidance type coder is longer than that of above-mentioned obstructing type coder because that the light is indirectly guided to the receiver 
20
. Moreover, before the receiver 
20
 the refracted light, the light has grown weaker already. In order to prevent the light guided to the receiver 
20
 from being attenuated, the intensity of the emitter 
10
 must be increased. More power consumption is needed and the lifetime of emitter 
10
 is shortened.
Referring to 
FIG. 3
, a traditional mechanical coder is depicted. The traditional mechanical coder consists of a signal-separating wheel 
40
, a common terminal 
54
, a first terminal 
52
 and a second terminal 
53
. Additionally, there are a first conductive portion 
41
, a plurality of second conductive portions 
42
, a plurality of third conductive portions 
43
 and an insulating portion 
43
 formed on a main surface of the signal-separating wheel 
40
 having a disk-shaped outline. It is worth noting that there are several ladders formed of one second conductive portion 
42
 and one third conductive portion 
43
. That is, for the first terminal 
52
 and the second terminal 
53
, each of second conductive portions 
42
 and each of third conductive portions 
43
 are not on the same level. However, the common terminal 
54
, the first terminal 
52
 and the second terminal 
53
 are placed on the same level and coupled to the main surface of the signal-separating wheel 
40
. While the signal-separating wheel 
40
 is rotating, the first terminal 
52
 and the second terminal 
53
, placed on the same level, continuously receive the “ON” signal or the “OFF” signal, respectively. The “ON” signal and the “OFF” signal constitute a digital logic signal.
The advantages of the traditional mechanical coder include lower power consumption, non-scattering, non-diffraction and longer lifetime. The traditional mechanical coder is generally employed in the wireless device, notebook or the device requiring lower power consumption. However, the disadvantages of the traditional mechanical coder are identified as follows.
(1) The signal-separating wheel is made from a general PCB (printed circuit board). Then the signal-separating wheel is etched or stamped. Thus the thickness of the first conductive portion, the second conductive portion and the third conductive portion may be slightly different from that of the insulating portion. That is, there is an altitude formed between the conductive portion and the insulating portion. This will result in bounce of the terminal, which leads to unstable signal and errors in receiving the signal.
(2) Because the signal-separating wheel is etched or stamped, there are many sharp teeth formed on the boundary of the conductive portion and the insulating portion. This will cause an unstable signal and errors in receiving the signal.
(3) The required precision is high and the extra work is difficult to do, so the yield is low.
(4) The common terminal, the first terminal and the second terminal are placed on the same level, and they are coupled to the main surface of the signal-separating wheel, so they suppress the rotation of the signal-separating wheel.
SUMMARY OF THE INVENTION
The present invention discloses a mechanical coder including a signal-separating wheel. The signal-separating wheel is manufactured in the following manner. First, a gear-shaped portion made of conductive material is formed. Then the recess of the gear-shaped portion is filled with insulating material to completely form the signal-separating wheel having a smooth disk-shaped outline. Thus the bounce of the terminal, caused by the altitude formed between the conductive portion and the insulating portion, is avoided.
The present invention also includes a first terminal, a second terminal and a common terminal. The first terminal and the second terminal are coupled to the opposite sides of the signal-separating wheel, respectively, rather than being placed on the main surface of the signal-separating wheel. This arrangement prevents the suppression of the rotating of the signal-separating wheel.
The first terminal, the second terminal and the common terminal are combined to form a terminal module. Thus the assembling time and the production cost are reduced effectively. Additionally, the yield is improved.
REFERENCES:
patent: 2974316 (1961-03-01), Guidal et al.
patent: 3024990 (1962-03-01), Magnuson
patent: 3206740 (1965-09-01), Maclay
patent: 4240069 (1980-12-01), Hullein et al.
Le Don Phu
Tokar Michael
LandOfFree
Mechanical coder does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Mechanical coder, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Mechanical coder will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2546398