Electrical pulse counters – pulse dividers – or shift registers: c – Applications – Measuring or testing
Reexamination Certificate
2001-01-10
2002-08-20
Wambach, Margaret R. (Department: 2816)
Electrical pulse counters, pulse dividers, or shift registers: c
Applications
Measuring or testing
C377S015000, C377S016000
Reexamination Certificate
active
06438193
ABSTRACT:
TECHNICAL FIELD OF THE INVENTION
The invention relates to monitoring rotation of a pneumatic tire, with Telemetry apparatus disposed in the tire.
BACKGROUND OF THE INVENTION
MONITORING TIRE CONDITIONS
It is known to remotely monitor conditions of pneumatic tires of motor vehicles. For example, telemetry devices comprising an RF transmitter and one or more condition sensors may be disposed in each of the tires. A transponder and associated conditions sensors (e.g., pressure, temperature) may also be disposed in pneumatic tires of motor vehicles. A “transponder” is an electronic device capable of both receiving and transmitting radio frequency (RF) signals. These transponders transmit a RF wave, with or without variable data (e.g., pressure, temperature) and/or fixed data (e.g., tire ID) to outside the tire, and receive RF signals, with or without data, from outside the tire. A separate transponder is typically associated with each tire of a motor vehicle to monitor and transmit tire-related data. Typically, a single “interrogator” having both transmitting and receiving capabilities is used to communicate with the plurality of transponders. The interrogator may be “hand-held”, or mounted “on-board” the vehicle, or positioned along or in a roadway (e.g., “drive-over”, or “drive by”).
“Active” transponders have their own power supply (e.g., a battery). They transmit signals, and are typically also capable of receiving signals to control their functionality.
“Passive” transponders are powered by the energy of an incoming RF signal, such as from an interrogator. Passive transponders fall into two general categories, those having only passive circuitry, and those having some active circuitry. In the main, transponders which are passive transponders having some active circuitry are discussed herein.
Transponder systems including a plurality of transponders and a single interrogator are well known and disclosed, for example, in U.S. Pat. No. 5,339,073 (Dodd, et al.; 1994), incorporated in its entirety by reference herein, which shows that both the interrogator and the individual transponders may comprise microprocessors. An example of a device for monitoring, storing and telemetering information such as temperature, pressure, tire rotations and/or other operating conditions of a pneumatic tire, along with tire identification information, can be found in U.S. Pat. No. 5,573,611 (Koch, et al.; 1996), incorporated in its entirety by reference herein.
FIG. 1A
illustrates a typical tire pressure monitoring system
100
of the prior art installed on a motor vehicle
102
(shown in dashed lines) having four pneumatic tires
104
a
. . .
104
d
installed on four respective wheels (not shown). A transponder (“TAG”)
106
a
. . .
106
d
is disposed within each of the tires
104
a
. . .
104
d
, respectively. The transponders
106
a
. . .
106
d
are preferably passive transponders which obtain their operating power from an RF signal such as is typically generated by an on-board interrogator
108
which is mounted within the vehicle. A sensor (not shown), such as a pressure sensor or a temperature sensor, is typically associated with each transponder
106
a
. . .
106
d.
The interrogator
108
comprises an RF transmitter
112
(e.g., for powering passive transponders), an RF receiver
114
, control logic
116
which may include a microprocessor (&mgr;P) , and a display device
118
such a visual display and optionally including an audible alarm. Antennas (“ANT”)
110
a
. . .
110
d
are disposed on the vehicle
102
, preferably adjacent the tires
104
a
. . .
104
d,
respectively, such as in the wheel wells of the vehicle. The antennas
110
a
. . .
110
d
are suitably ferrite loopstick antennas.
The use of multiple vehicle antennas
110
a
. . .
110
d,
each at a fixed position on the vehicle adjacent a respective tire
104
a
. . .
104
d
is well known and preferred, and is disclosed in U.S. Pat. Nos. 3,553,060; 3,810,090; 4,220,907; 5,541,574; and 5,774,047, all of which are incorporated in their entirety by reference herein.
In use, the interrogator
108
powers the transponders
106
a
. . .
106
d
which, in turn, transmit data indicative of a measured condition (e.g., air pressure) back to the interrogator. In any such system, it is desirable to have efficient and effective coupling of signals between the fixed antennas
110
a
. . .
110
d
(alternatively, one centrally-located fixed antenna) and the moving (i.e., when the vehicle is in motion) transponders (each of which has its own antenna, not shown).
FIG. 1B
illustrates, generally, the physical arrangement of a transponder
106
(representative of any one of the transponders
106
a
. . .
106
d
) disposed within a pneumatic tire
104
(representative of any one of the tires
104
a
. . .
104
d
). The transponder
106
is mounted in any suitable manner to an inner surface
105
of the tire
104
. An antenna
110
(representative of any one of the antennas
110
a
. . .
110
d
) is disposed on the vehicle near the tire
104
such as in a wheel well, to provide electromagnetic radiation to power the transponder
106
(in the case of a passive transponder) , as well as to receive signals from the transponder
106
.
REVOLUTION COUNTERS
In many industries there exists a need for a device capable of automatically counting revolutions of a rotating element, storing a data count, and transferring the data to a computing device for manipulation. The degree of accuracy (or resolution, required varies from a count of complete revolutions or rotations (low resolution) to a measurement of partial revolutions in very small increments (high resolution). Monitoring revolutions of vehicle tires is of particular interest with regard to the present invention.
U.S. Pat. No. 3,613,075 (Griffiths; 1971), incorporated In its entirety by reference herein, discloses monitoring tire inflation by sensing the angular movement of a wheel by counting revolutions of the wheel and comparing the count with a count from another wheel or a reference to determine whether or not the wheel has the proper diameter (hence, proper inflation). For counting revolutions of a wheel, a block of metal is mounted for rotation on the brake drum of the wheel and projects radially outwardly to pass in close proximity to a pickup which may be a normally open switch which is held closed by the attraction of a permanent magnet forming a part of the switch mechanism. Counting circuits are disclosed in this patent. See also U.S. Pat. No. 3,691,524 (Frost, et al. 1972).
U.S. Pat. No. 5,524,034 (Srygley, et al.; 1996), incorporated in its entirety by reference herein, discloses an automatic revolution counting and data transmission device in the form of a hub-odometer for measuring rotations of a wheel on a vehicle. The use of reed switches (
9
) and a magnet (
14
) for detecting rotation is described. The switches provide signals which relate directly to the revolution of the hub unit. These signals are processed into a suitable machine-readable format for use by a microcontroller (7) As noted in the patent (column
3
, lines
28
-
30
), “the signal must be lengthened, de-bounced, and output at the correct signal level. The signal conditioner (
8
) takes care of this task.” The possibility of using optical sensors, gear tooth sensors, Hall effect devices, and contact sensors in lieu of the reed switches and magnets for sensing rotation is disclosed.
U.S. Pat. No. 4,862,486 (Wing, et al.; 1989), incorporated in its entirety by reference herein, discloses a revolution counter that is attached to the vehicle tire. As aptly noted in this patent, a problem with mechanical counters attached to the axle or wheel hub is that by not being mounted to the tire itself, the counter must be changed or separate records must be maintained whenever the tire is changed to maintain a proper count for a given tire. This patent describes revolution-counting apparatus comprising a piezoelectric polymer sensor (
5
) which senses a change in stress as a given section of a tire is stressed with each
Ko Wen H.
Xie Huijun
Cohn Howard M.
Wambach Margaret R.
LandOfFree
Self-powered tire revolution counter does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Self-powered tire revolution counter, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Self-powered tire revolution counter will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2897749