GB2425841A - Electronic environment sensing instrument having an analog indicator - Google Patents
Electronic environment sensing instrument having an analog indicator Download PDFInfo
- Publication number
- GB2425841A GB2425841A GB0509042A GB0509042A GB2425841A GB 2425841 A GB2425841 A GB 2425841A GB 0509042 A GB0509042 A GB 0509042A GB 0509042 A GB0509042 A GB 0509042A GB 2425841 A GB2425841 A GB 2425841A
- Authority
- GB
- United Kingdom
- Prior art keywords
- gear
- front panel
- environment sensing
- sensing instrument
- microprocessor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
- G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
- G01D2213/00—Indexing scheme relating to constructional details of indicators
- G01D2213/10—Drivers for gauges
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Arrangements For Transmission Of Measured Signals (AREA)
Abstract
An electronic environment sensing instrument having an analog indicator has a casing having a front panel with a scale, an electromic sensing and driving assembly 20 mounted in the casing, a needle 15 and a DC power supply. The electronic driving indicator assembly 20 has a detecting and driving circuit to sense and measure an environmental parameter outside the casing and to generate a control signal, a drive unit to receive the control signal and to rotate a specific amount in a specific direction based on the control signal and a gear assembly 30, 31, 32, 33 , 34 connected to and driven by the drive unit 40. The needle 15 is attached to and driven by the gear assembly 30, 31, 32, 33, 34 and points to a specific value on the scale corresponding to the sensed environmental parameter.
Description
ELECTRONIC ENVIRONMENT SENSING INSTRUMENT HAVING
AN ANALOG INDICATOR
1. Field of the Invention
The present invention relates to an electronic environment sensing instrument and more particularly to an electronic environment sensing instrument having an analog indicator that points to a specific point on a scale corresponding to a sensed environmental parameter such as temperature, humidity or the like.
2. Description of Related Art
Two types of conventional environmental sensing instruments are available in the market and include thermometers, hygrometer, anemometers and the like. One is a mechanical instrument, and the other is an electronic instrument. The mechanical instrument has an analog indicator that indicates the current reading and can drive indicators to mark high and low readings for a given period. The digital instrument provides a precise digital readout of the current reading.
With reference to Fig. 9, a conventional mechanical thermometer has a panel (90), a Borden tube assembly (70) and an indicator set (80).
The panel (90) has a front face (not numbered), a scale (not numbered) a through hole (91) and optional high and low indicators (not shown). The scale is on the front face (not numbered), is printed or etched and is a temperature scale, a relative humidity scale or the like. The high and low indicators are pivotally attached to the front face of the panel (90) and respectively indicate high and low readings on the scale.
The Borden tube assembly (70) has a base (71), a copper C-ring (72) and a transmission shaft (73). The base (71) has a front surface (not numbered) and a pivot hole (711). The hole (711) is defined in the front surface of the base (71). The copper C-ring (72) has a proximal end (not numbered) and a distal end (not numbered), is connected to the base (71) and expands or contracts depending on the temperature. The transmission shaft (73) is connected to distal end of the copper ring (72) and has an L-shaped distal end (731).
The indicator (80) is L-shaped and has a shaft (81), a needle (82) and a connector (83). The shaft (81) is mounted through the through hole (91) in the panel (90), rotatably mounted in the hole (711) in the base (71) and has a distal end (not numbered). The distal end protrudes through the through hole (91) in the panel (90). The needle (82) is connected to the distal end of the shaft (81), pivots the high and low indicators on the front face of the panel (90) and indicates the current temperature on the scale on the panel (90). The connector (83) is attached to the shaft (81) and has a mounting hole (831). The mounting hole (831) rotatably holds the L-shaped distal end (731) of the transmission shaft (73) that rotates the shaft (81) in the pivot hole (711) in the base (71) to indicate the current temperature on the scale on the panel (90) when the copper C-ring (72) expands or contracts.
Because the specific current environmental parameter has to be interpolated from the scale on the panel (90) of the device, electronic instruments were designed to provide a precise digital readout of the current sensed environmental parameter. Even though the electronic instruments provide precise instantaneous readings of the current environmental parameter, the electronic environment sensing instrument cannot provide high and low readings without a significant increase in the electronics or the software.
Therefore, the present invention provides an electronic environment sensing instrument that has an analog indicator to obviate or mitigate the problems with conventional mechanical and electronic environment sensing instruments.
The main objective of the present invention is to provide an electronic environment sensing instrument having an analog indicator. The electronic environment sensing instrument precisely senses an instantaneous environmental parameter such as temperature, humidity or the like and points an indicator to the exact value of the instantaneous environmental parameter on a scale on a panel.
The electronic environment sensing instrument has a casing, an electronic sensing and driving assembly, a needle and a DC power supply. The casing has a front panel with a scale. The electronic sensing and driving assembly is mounted in the casing and has a sensing and driving circuit, a drive unit and a gear assembly, a needle and a DC power. The detecting and driving circuit senses and measures an environmental parameter outside the casing and generates a control signal. The drive unit receives the control signal from the detecting and driving circuit and rotates a specific amount in a specific direction based on the control signal. The gear assembly is connected to and driven by the drive unit. The needle is attached to and driven by the gear assembly and points to a specific value on the scale on the front panel of the casing corresponding to the sensed and measured environmental parameter.
The DC power supply is mounted in the casing and is attached to the electronic sensing and driving assembly.
IN THE DRAWINGS
Fig. I is a front view of an embodiment of an electronic environment sensing instrument having an analog indicator in accordance with the present invention implemented as a thermometer; Fig. 2 is a perspective rear view of the electronic environment sensing instrument in Fig.l; Fig. 3 is an exploded perspective view of an electronic driving assembly in an electronic sensing and driving assembly in the electronic environment sensing instrument in Fig. 2; Fig. 4 is a cross sectional perspective view of the electronic driving assembly in Fig. 3; Fig. 5 is a top view of the electronic driving assembly in Fig. 3; Fig. 6 is a functional block diagram of a first embodiment of a sensing and driving circuit in the sensing and driving assembly in Fig. 2; Fig. 7 is a functional block diagram of a second embodiment of a sensing and driving circuit in the sensing and driving assembly in accordance with the present invention; Fig. 8 is an operational perspective view of a second embodiment of an electronic environment sensing instrument having an analog indicator in accordance with the present invention; and Fig. 9 is an exploded perspective view of a conventional mechanical
thermometer in accordance with the prior art.
With reference to Figs. 1, 2 and 8, an electronic environment sensing instrument (10) in accordance of the present invention has a casing (11), an electronic sensing and driving assembly (20), a needle (15) and a DC power supply (16).
The casing (11) has a front panel (12). The front panel (12) has a front face, a rear face, a central through hole (13) and optional multiple indicator holes (14). The front face has at least one scale corresponding to a sensed and measured environmental parameter.
With further reference to Fig. 3, the electronic sensing and driving assembly (20) is attached to the rear face of the front panel (12) and has a detecting and driving circuit (50), a drive unit (40), a gear assembly, an optional driving assembly casing (35) and an optional remote sensing unit (57).
In a first embodiment of the electronic environment sensing instrument (10), the entire electronic sensing and driving assembly (20) is attached to the rear face of the casing (11). In a second embodiment of the electronic environment sensing instrument (10), sensing elements of the electronic sensing and driving assembly (20) are mounted remotely from the casing (11) and communicate with wireless elements.
With reference to Figs. 3, 4 and 5, the gear assembly has a main gear (30), a decelerating gear set (31), a linking gear (32) and a connector (33).
The main gear (30) is connected to the drive unit (40). The drive unit (40) rotates the main gear (30). The decelerating gear set (31) has multiple gear elements (31l--313), each of which has a small drive gear (311b313b) and a large driven gear (31 1a-3 13a). The linking gear (32) has a central axis and a central hole defined coaxially in the linking gear (32).
In the first embodiment, the decelerating gear set (31) has a first gear element (311), a second gear element (312) and a third element (313). The large driven gear (311 a) of the first gear element (311) engages the main gear (30), and the small drive gear (31 ib) engages the large driven gear (3 12b) of the second gear element (312). The small drive gear(312a) of the second gear element (312) engages the large driven gear (313a) of the third gear element (313). The small drive gear (313b) of the third gear element (313) engages the linking gear (32). The center axis of the linking gear (32) is connected to the connector (33). With further reference to Fig. 1, the connector (33) is mounted in the through hole (13) in the casing (11) to hold the needle (15) outside the front face. Based on the connection of the main gear (30), the decelerating gear set (31), the linking gear (32), the connector (33) and the needle (15), the needle (15) will be precisely rotated in small increments when the main gear (30) is driven by the drive unit (40).
The drive unit (40) has a clockwise winding (41), a counterclockwise winding (42) and a ring magnet (43). The clockwise winding (41) and counterclockwise winding (42) are mounted on the rear face perpendicular to each another. Each winding (41, 42) has a U-shaped yoke (411, 421) and a coil (412, 422) wound around the yoke (411,421). Each yoke (411, 421) has an opening and two opposite arms. The coils (412, 422) are wound around one arm respectively of the yokes (411, 421) and are connected to the detecting and driving circuit (50). The openings of the yokes (411, 421) respectively on the clockwise winding (41) and counterclockwise winding (42) are perpendicular to each another. The ring magnet (43) is mounted rotatably in the two openings and attached securely to the main gear (30). When the detecting and driving circuit (50) outputs a voltage to one of the coils (412, 422), a magnetic field is generated in the corresponding yoke (411, 421) to rotate the ring magnet (43).
When the voltage is input to the coil (412) of the clockwise winding (41), the ring magnet (43) is rotated clockwise. If the ring magnet (43) rotates counterclockwise, the will be input to the coil (422) of the counterclockwise winding (42). Therefore, the rotating direction of the needle (15) is confrolled by the detecting and driving circuit (50).
Further, to minimize space required for the gear assembly and the drive unit (40), a board (34) is mounted on the rear face of the of the front panel (12) and corresponds to the central through hole (13) in the front panel (12). The board (34) is mounted on multiple posts (341) formed on the rear face, so a gap is formed between the rear face and the board (34) . The board (34) has an upper face, a magnet recess (342), a pin hole (343) and at least one drive gear hole (344). The magnet recess (342) is formed on the upper face of the board (34) and rotatably holds the ring magnet (43). The pin hole (343) is formed through the board (34) and corresponds to the central through hole (13) in the front panel (12). At least one drive gear hole (344) is defined through the board (34) to allow the main gear (30) or a small drive gear (31 ib, 3 12b, 3 13b) to extend through the board (34) and engage a corresponding large driven gear (3lla, 3l2a, 3l3a) or the linking gear (32). Since the main gear (30) is connected to the ring magnet (43), the decelerating gear set (31) is mounted on the upper face of the board (34), and the linking gear (32) is mounted under the board (34). To allow the third gear element (313) to engage the linking gear (32), the small drive gear (31 3b) passes through the drive gear hole (344) and engages the linking gear (32) under the board (34). The second gear element (312) further has a pin (314) coaxially mounted in the small drive gear (3 12b).
The pin (314) is mounted rotatably in the pin hole (343).
To implement the electronic sensing and driving assembly (20) as a module, a driving assembly casing (35) can be added to hold the electronic sensing and driving assembly (20). The driving assembly casing (35) is directly attached to the rear face of the casing (11).
With further reference to Fig. 6, a first embodiment of the detecting and driving circuit (50) has a microprocessor (51), a sensor (53), a signal converter (531), a motor driver (52) and an optional status indicator (54). The microprocessor (51) calculates a value for a sensed environmental parameter, generates a control signal and has multiple inputs and outputs. The sensor (53) can be a temperature sensor, humidity sensor or the like, senses and measures an appropriate environmental parameter, such as temperature, humidity or the like, outside the casing (11), is connected to the inputs of the microprocessor (51) through the signal converter (531) and sends a sensed signal to microprocessor (51). The signal converter (53 1) is connected to an input of the microprocessor (51), can be an analog to digital converter, receives a sensed parameter from the sensor (53), converts the sensed parameter and sends the converted sensed parameter to the microprocessor (51). The motor driver (52) is connected to an output of the microprocessor (51), receives a control signal from the microprocessor (Si) and sends a corresponding voltage to the appropriate coil (412, 422) of the winding (41, 42) to rotate the needle (15) to the correct value on the scale on the front panel (12). The status indicators (54) are connected to outputs of the microprocessor (51) and indicate the status of selected elements. The status indicator (54) can be an LED set or a LCD. The status indicator (54) may be an LED set having three different color LED elements. Each LED element is mounted in a corresponding indicator hole (14) on the front face of the front panel (12). The front face of front panel (12) may have different symbols for various parameters such as battery voltage, signal searching, etc. The symbols correspond respectively to the LED elements.
With reference to Fig. 7, a second embodiment of the detecting and driving circuit in accordance with the present invention has a wireless detector (57) and a controller (60). The wireless detector (57) has a sensor (53), a wireless signal transmitter (55) and a DC power supply (58). The sensor (53) detects the instantaneous environmental parameter and generates a detection signal. and sends the detection signal to the wireless signal transmitter (55).
The wireless signal transmitter (55) connected to the sensor (53), receives the detection signal from the sensor (53), converts the detection signal to a wireless detection signal and transmits the wireless detection signal.
The controller (60) has a microprocessor (51), a wireless signal receiver (56), a motor driver (52) and an optional status indicator (54).
The wireless signal receiver (56) is connected to an input of the microprocessor (5 1), receives the wireless detection signal transmitted by the wireless signal transmitter (55) and outputs the detection signal to the microprocessor (51). Therefore, the wireless detector (58) is separated from the detecting and driving circuit to implement to an independent sensing instrument. With reference to Fig. 8, the wireless detector (58) can be mounted anywhere, and the needle points to a value on the scale on the front panel (12) corresponding to the value of the sensed environmental parameter outside the wireless detector.
The DC power supply (16) is attached to the rear face of the casing (11) and connected to the drive unit (40) and the detecting and driving circuit (50) to provide them DC power. The DC power supply (16) can use a battery set. Ii
Claims (10)
- CLAIMS: 1. A electronic environment sensing instrument having an analogindicator, comprising: a casing (11) having a front panel (12) with a front face having at least one scale; a rear face; and a central through hole(13); an electronic driving indicator assembly (20) attached to the rear face of the front panel (12) and having a detecting and driving circuit (50); a drive unit (40); and a gear assembly, wherein the drive unit (40) is connected between the gear assembly and the detecting and driving circuit (50); a needle (15) connected to the gear assembly of the electronic driving indicator assembly (20) outside the front face of the front panel (12); and a DC power supply (16) attached to the rear face of the casing (11) and connected to the drive unit (40) and the detecting and driving circuit (50).
- 2. The electronic environment sensing instrument as claimed in claim 1, wherein the gear assembly comprises: a main gear (30) connected to the drive unit (40); a decelerating gear set (31) having multiple gear elements (311-313), each of which mainly has a small drive gear (3 11 b-3 1 3b) and a large driven gear (311 a3 13 a), wherein the gear elements (3 11 -3 13) sequentially engage each other, and a first gear element (311) engages the main gear (30); a linking gear (32) engaging a last gear element of the decelerating gear set (31) and having a center axis; and a connector (33) connected coaxially to the linking gear (32), passing through the central through hole (13) in the front panel (12) and holding the needle (15).
- 3. The electronic environment sensing instrument as claimed in claim 1, wherein the drive unit (40) comprises: a clockwise winding (41) and a counterclockwise winding (42) mounted on the rear face of the front panel (12) perpendicular to each another, each winding (41, 42) having a Ushaped yoke (411, 412) with an opening and two opposite arms and a coil (412, 422) wound around one arm of the yoke (411,412), wherein the coils (412, 422) are connected to the detecting and driving circuit (50), and the two openings are perpendicular to each another; and a ring magnet (43) mounted in the two openings and connected to the main gear (30).
- 4. The electronic environment sensing instrument as claimed in claim 3, wherein the gear assembly further comprises a board (34) mounted on the rear face of the front panel (12), corresponding to the central through hole (13) in the front panel (12) and having an upper face; a magnet recess (342) formed on the upper face of the board (34) to hold the ring magnet (43); a pin hole (343) formed through the board (34) and corresponding to the central through hole (13) in the front panel (12), wherein one of the gear elements (312) is mounted in the pin hole (343) and rotates on the board (34); and at least one drive gear hole (344) defined on the board (34), through which a small drive gear extends to drive an adjacent driven gear; and multiple posts (341) formed on the rear face of the front panel (12) on which the board (34) is mounted to form a gap between the rear face and the board (34); and a case (35) attached to the rear face of the front panel (12) to hold the electronic driving indicator assembly (20).
- 5. The electronic environment sensing instrument as claimed in claim 1, wherein the detecting and driving circuit (50) comprises: a microprocessor (51) calculating a value for a sensed environmental parameter, generating a control signal and having multiple inputs and outputs; a sensor (53) sensing and measuring an appropriate environmental parameter outside the casing (11); a signal converter (531) connected to an input of the microprocessor (51), receiving a sensed parameter from the sensor, converting the sensed parameter and sending the converted sensed parameter to the microprocessor (51); and a motor driver (52) connected to an output of the microprocessor (51) and the coils (412, 422), receives the control signal from the microprocessor (51) and sending a corresponding voltage to the appropriate coil (412,422) of winding (41, 42) to rotate the needle (15) to the correct value on the scale on the front panel (12).
- 6. The electronic environment sensing instrument as claimed in claim 1, wherein the detecting and driving circuit (50) comprises: a wireless detector (57) having a sensor (53); a wireless signal transmitter (55) connected to the sensor (53); and a DC power supply (58) connected to the sensor (53) and the wireless signal transmitter (55); and a controller (60) having: a microprocessor (51) having multiple inputs and outputs; a wireless signal receiver (56) connected to the inputs of the microprocessor (51); and a motor driver (52) connected between the outputs of the microprocessor (51) and the coils (412, 422) of he windings (41, 42).
- 7. The electronic environment sensing instrument as claimed in claims or 6, further comprising a status indicator (54) connected to the outputs of the microprocessor (51).
- 8. The electronic environment sensing instrument as claimed in claim 5 or 6, wherein the sensor (53) is a temperature sensor.
- 9. The electronic environment sensing instrument as claimed in claim 5 or 6, wherein the sensor (53) is a humidity sensor.
- 10. The electronic environment sensing instrument as claimed in claim or 6, wherein the signal converter (531) is an analog to digital converter.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB0509042A GB2425841B (en) | 2005-05-04 | 2005-05-04 | Electronic environment sensing instrument having an analog indicator |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB0509042A GB2425841B (en) | 2005-05-04 | 2005-05-04 | Electronic environment sensing instrument having an analog indicator |
Publications (3)
Publication Number | Publication Date |
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GB0509042D0 GB0509042D0 (en) | 2005-06-08 |
GB2425841A true GB2425841A (en) | 2006-11-08 |
GB2425841B GB2425841B (en) | 2008-03-26 |
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ID=34674282
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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GB0509042A Expired - Fee Related GB2425841B (en) | 2005-05-04 | 2005-05-04 | Electronic environment sensing instrument having an analog indicator |
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GB (1) | GB2425841B (en) |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4008618A (en) * | 1974-03-25 | 1977-02-22 | Edo-Aire Mitchell Industries, Inc. | Flight instrument |
US4314146A (en) * | 1978-11-21 | 1982-02-02 | Jean-Claude Berney | Analog display device |
GB2164152A (en) * | 1984-06-02 | 1986-03-12 | Citizen Watch Co Ltd | Pointer type measuring instrument |
EP0632351A1 (en) * | 1993-06-30 | 1995-01-04 | Casio Computer Co., Ltd. | Electronic applicance equipped with sensor capable of visually displaying sensed data |
DE20101505U1 (en) * | 2001-01-30 | 2002-06-13 | Wallrafen Werner | Device for displaying weather data on a screen |
JP2003294779A (en) * | 2002-03-29 | 2003-10-15 | Koshin Denki Kogyo Kk | Wind direction and wind speed indicating device |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0736689B2 (en) * | 1986-07-21 | 1995-04-19 | キヤノン株式会社 | Step Motor |
DE19504387A1 (en) * | 1995-02-11 | 1996-08-22 | Dufa Deutsche Uhrenfabr Gmbh | Stepper motor |
-
2005
- 2005-05-04 GB GB0509042A patent/GB2425841B/en not_active Expired - Fee Related
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4008618A (en) * | 1974-03-25 | 1977-02-22 | Edo-Aire Mitchell Industries, Inc. | Flight instrument |
US4314146A (en) * | 1978-11-21 | 1982-02-02 | Jean-Claude Berney | Analog display device |
GB2164152A (en) * | 1984-06-02 | 1986-03-12 | Citizen Watch Co Ltd | Pointer type measuring instrument |
EP0632351A1 (en) * | 1993-06-30 | 1995-01-04 | Casio Computer Co., Ltd. | Electronic applicance equipped with sensor capable of visually displaying sensed data |
DE20101505U1 (en) * | 2001-01-30 | 2002-06-13 | Wallrafen Werner | Device for displaying weather data on a screen |
JP2003294779A (en) * | 2002-03-29 | 2003-10-15 | Koshin Denki Kogyo Kk | Wind direction and wind speed indicating device |
Also Published As
Publication number | Publication date |
---|---|
GB2425841B (en) | 2008-03-26 |
GB0509042D0 (en) | 2005-06-08 |
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Legal Events
Date | Code | Title | Description |
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PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 20130504 |