CA2061154A1 - I.v. alert system - Google Patents
I.v. alert systemInfo
- Publication number
- CA2061154A1 CA2061154A1 CA002061154A CA2061154A CA2061154A1 CA 2061154 A1 CA2061154 A1 CA 2061154A1 CA 002061154 A CA002061154 A CA 002061154A CA 2061154 A CA2061154 A CA 2061154A CA 2061154 A1 CA2061154 A1 CA 2061154A1
- Authority
- CA
- Canada
- Prior art keywords
- intravenous
- alert system
- counter
- signal
- audio frequency
- 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.)
- Abandoned
Links
Abstract
ABSTRACT OF THE DISCLOSURE
An intravenous alert system that uses CMOS circuitry. An infrared transmitter and receiver detects drops as they fall through a drip chamber. Each passing drop retriggers a counter.
If the counter is not retriggered after a certain set delay time an alarm signal is sent out. The device uses both audio and visual alarms. A special adjustable housing contains all of the electronic components of the alert system.
An intravenous alert system that uses CMOS circuitry. An infrared transmitter and receiver detects drops as they fall through a drip chamber. Each passing drop retriggers a counter.
If the counter is not retriggered after a certain set delay time an alarm signal is sent out. The device uses both audio and visual alarms. A special adjustable housing contains all of the electronic components of the alert system.
Description
-` 2 ~ 4 TITLE OF THE INVENTION
I.V. ALERT SYSTEM
BACKGROUND OF THE INVENTION
FIELD OF THE INVENTION
The present invention relates to the field of alar~ devices usinq CMOS (Complimentary Metal O~ide Semiconductor) di~ital circuitry. More sPecifically it is a driP I.V. alarm used to alert the user that an intravenous infusion therapy has been comPleted. The invention has Photovoltaic cells to detect each drop in an I.V. chamber. Each successive droD retriggers a counter. A lon~ pause after a drop will set off alarm circuitrY
to warn of the comPleted I.V. infusion.
DESCRIPTION OF THE PRIOR ART
The followinq is a discussion of Patents felt to be related in the field of the Present invention. but do not disclose, whether sinqly or in combination, the aPplicants' unique construction.
U.S. Patent No. 4.681.569 issued to StePhen Coble discloses a batterv-operated rate meter used for monitorin~ the fluid flow of an intravenous feedin~ sYstem which comprises a housin~ havin~
li~ht emitters Positioned opposite one another about the base of the drip chamber. The said rate meter calculates the passa~e of drops usin~ photo-detectin~ properties therein and disPlays the detected inPut throu~h LED indicator means.
U.S. Patent No. 4,014,010 issued to Walter Jinotti discloses a device similar to the patent described above in that the intravenoUs ystem flo~ meter ComDrisinq liqht detector means and electronic circuitrY therein is used in combination with an alarm circuit havinq audio si~naling means to warn the oPerator of fluid flow drippinq below the set level.
SUMMARY OF THE INVENTION
The present invention is a small. portable I.V. alarm system. The alarm circuitry consists of CMOS di~ital electronics. The detector com~rises an infrared photocell chamber having an emitter side and a receiver sids. The emitter and receiver are positioned on either side of an I.V. drip chamber. Drops that Pass through the emitter beam interrupt the constant volta~e sent by the receiver. A volta~e comparator sends a si~nal to tri~qer a counter, which counts up to a certain set delay time. If the counter is not retri~ered bY another drop at the end of the countin~ sequence. an alarm oscillator is set in action to operate an alarm buzzer and a visible LED (Ei~ht Emittin~ Diode). The device can be set in terms of the len~th of i allowable time delay for the counter and the alarm can be turned off after an initial si~nal to reset the system as a whole.
Accordin~lY, it is an ob~ject of the present invention to ~rovide a Portable I.V. drip alarm system.
Another obiect of the present invention is to Provide an I.V. alarm system usinq CMOS circuitry.
It is a further obiect of the present invention to provide an I.V. alarm system usin~ infrared Photovoltaic cells.
It is still another ob~ect of the present invention to Drovide an I.V. alarm system with an user-ad~ustable timin~
circuit.
These and other obiects of the present invention will 2 ~
readily become aPDarent uPon review of the attached drawings and sPecification.
BRIEF DES~RIPTION OF THE DRAWINGS
Fig. 1 shows a perspective view of the portable I.V. alarm system with the driP chamber in outline.
Fig. 2 shows a top view of the I.V. alert system.
Fig. 3 shows a bottom view of the I.V. alert system.
Fig. 4 shows a rear view of the I.V. alert system.
Fig. 5 shows a side view of the I.V. alert system.
Fig. 6 shows a circuit diagram for the I.V. alert system.
Similar reference characters denote corresponding parts throughout the drawings.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Fig. 1 shows the Packaged alarm system 10 having a plastic casing 11, reset switch 12, alarm sPeaker 37 and an LED indicator 38. The system has two seParate housing or containment sections 1la and 11b that are Placed on either side of an I.V. drip cham-ber 23. A plurality of arms 13 slide through a bracket 14 having separate passages 14a for each arm 13, as shown in Fig. 4, allow-ing the width of the ~aP between the channels 11c,11c on the two sections 11a, 11b to be ad~iusted in order to accommodate differ-ent sized driP chambers 23. The whole outer housing assembly 11 can be constructed from a relatively soft, resilient plastic which would allow arms 13 and brackets 14 to have an easily slidable friction fit.
Recharger contacts 18 and battery door 17. shown in Figs. 3 and 5. are provided on the side and on the bottom of housing section 11a. Also included on the housing 11 are 5 or more DIP
(Dual Inline Packaqe) switches 34 that ad~just the alert period between drops 24 in the drip chamber 23. and an on-off switch 39.
To connect the various components in the two housin~s 11a,11b a connecting line(not shown) would be sent throu~h or ad~iacent to the arm 13 and bracket 14 assemblY. The alarm system 10 is small enough to fit within a normal shirt pocket, bein~ no more than 4 inches by 2 1/8 inches by 7/8 inches thick.
The photovoltaic cell is shown in Fi~s. 1, 2, 3 and 6. The cell consists of a singular emitter 21 and receiver 22 spaced opposite each other in the channels 11c of sections 11a and 11b.
The sPecific device used to emit is an infrared diode 21 which emits a beam of infrared light through a clear I.V. drip chamber 23 to an infrared detector 22. The advanta~e of usin~ infrared li~ht instead of visible light is that there will be less inter-ference from the outside visible light sources around the device.
The receiver 22 receives a constant si~nal from the emitter 21 until a droP 24 intercepts the path between emitter 21 and re-ceiver 22. The interDosing of the drop 24 between the emitter diode 21 and the receiver 22 changes the receiver's incomin~
si~nal. The receiver 22 is constantly sending out a signal to the alarm circuitry. This receiver output is chan~ed accordingly and causes a reaction in the alarm circuitry as will be detailed below.
The alarm circuitry contains a power source for the whole device. Nickel-cadmium batteries ~0 of 7.2 volt type are used because of their long life. These types of batteries are also easily rechargeable. hence the rechargin~ ports 18 consistin~ of a common DC port connectable to a conventional batterY recharger 54 which is operable to rechar~e batteries 50 only when on-off switch 59 is in the off position and the alarm system is not being used~ as is well known in the battery recharging art.
These batteries 50 should keeP the alarm device functional for about 5 hours as the device has low power requirements with CMOS
~circuitry.
Fiq. 6 shows the circuit diagram for the device. Sensor blocl; 31 consists of an emitter and receiver 21.22. A voltaqe comparator 32 is constantlY checking for voltage fluctuations.
If it detects one, a signal uulse is sent to a counter 33 (4541 type) which begins a countinq sequence. Should another pulse be sent bY the comparator 32. the counter 33 will be retriggered to start at the beginnin~. A five-position DIP switch 34, also shown in Fig. 3, allows the user to set the maximum drop delay time for the counter 33. Should the counter 33 reach this maxi-mum delaY count without beinq retriggered bY a comparator Pulse~
the counter 33 outPuts a Pulse to an AF (Audio Frequency~ 1/2 556C tYpe) oscillator 35, which will in turn output a pulse to an astable modulating oscillator (1~2 556C tYpe) 36. The modulating oscillator 36 is connected to a Piezo audio transducer or speaker 37 which produces the alarm sound. The two oscillators 35~36 are capable of producin~ a variety of sounds. A modulated single tone ~on-off-on-off)~ a modulated dual tone (hi~h-low-high-low) or an unmodulated sin~le tone. The type of tone can be selected by the user of the device 10.
A low power visual alarm LED 38 is connectQd to the outPut of another CMOS timer/multivibrator 52 (555C type) similar to oscillator 36 which is also controlled by the reset pulse of the driP sensing comparator 32. Oscillator timings of 100 ms are good for viewin~. Reset switch 12 would send a pulse back to the 2 ~ J ~l counter 33 to retri~qer its sequence separately of the voltage comparator 32.
In use the maximum desired delay time is about 20 seconds.
The five-position DIP switch 34 can select a range between 20 seconds and zero time between droPs in the I.V. chamber 23. The DIP switch 34 could have a variable amount of positions. Five are taken as a good sampling of driP times.
It is to be understood that the Present invention is not limited to the sole embodiment described above, but encompasses any and all embodiments within the scoPe of the following claims.
I.V. ALERT SYSTEM
BACKGROUND OF THE INVENTION
FIELD OF THE INVENTION
The present invention relates to the field of alar~ devices usinq CMOS (Complimentary Metal O~ide Semiconductor) di~ital circuitry. More sPecifically it is a driP I.V. alarm used to alert the user that an intravenous infusion therapy has been comPleted. The invention has Photovoltaic cells to detect each drop in an I.V. chamber. Each successive droD retriggers a counter. A lon~ pause after a drop will set off alarm circuitrY
to warn of the comPleted I.V. infusion.
DESCRIPTION OF THE PRIOR ART
The followinq is a discussion of Patents felt to be related in the field of the Present invention. but do not disclose, whether sinqly or in combination, the aPplicants' unique construction.
U.S. Patent No. 4.681.569 issued to StePhen Coble discloses a batterv-operated rate meter used for monitorin~ the fluid flow of an intravenous feedin~ sYstem which comprises a housin~ havin~
li~ht emitters Positioned opposite one another about the base of the drip chamber. The said rate meter calculates the passa~e of drops usin~ photo-detectin~ properties therein and disPlays the detected inPut throu~h LED indicator means.
U.S. Patent No. 4,014,010 issued to Walter Jinotti discloses a device similar to the patent described above in that the intravenoUs ystem flo~ meter ComDrisinq liqht detector means and electronic circuitrY therein is used in combination with an alarm circuit havinq audio si~naling means to warn the oPerator of fluid flow drippinq below the set level.
SUMMARY OF THE INVENTION
The present invention is a small. portable I.V. alarm system. The alarm circuitry consists of CMOS di~ital electronics. The detector com~rises an infrared photocell chamber having an emitter side and a receiver sids. The emitter and receiver are positioned on either side of an I.V. drip chamber. Drops that Pass through the emitter beam interrupt the constant volta~e sent by the receiver. A volta~e comparator sends a si~nal to tri~qer a counter, which counts up to a certain set delay time. If the counter is not retri~ered bY another drop at the end of the countin~ sequence. an alarm oscillator is set in action to operate an alarm buzzer and a visible LED (Ei~ht Emittin~ Diode). The device can be set in terms of the len~th of i allowable time delay for the counter and the alarm can be turned off after an initial si~nal to reset the system as a whole.
Accordin~lY, it is an ob~ject of the present invention to ~rovide a Portable I.V. drip alarm system.
Another obiect of the present invention is to Provide an I.V. alarm system usinq CMOS circuitry.
It is a further obiect of the present invention to provide an I.V. alarm system usin~ infrared Photovoltaic cells.
It is still another ob~ect of the present invention to Drovide an I.V. alarm system with an user-ad~ustable timin~
circuit.
These and other obiects of the present invention will 2 ~
readily become aPDarent uPon review of the attached drawings and sPecification.
BRIEF DES~RIPTION OF THE DRAWINGS
Fig. 1 shows a perspective view of the portable I.V. alarm system with the driP chamber in outline.
Fig. 2 shows a top view of the I.V. alert system.
Fig. 3 shows a bottom view of the I.V. alert system.
Fig. 4 shows a rear view of the I.V. alert system.
Fig. 5 shows a side view of the I.V. alert system.
Fig. 6 shows a circuit diagram for the I.V. alert system.
Similar reference characters denote corresponding parts throughout the drawings.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Fig. 1 shows the Packaged alarm system 10 having a plastic casing 11, reset switch 12, alarm sPeaker 37 and an LED indicator 38. The system has two seParate housing or containment sections 1la and 11b that are Placed on either side of an I.V. drip cham-ber 23. A plurality of arms 13 slide through a bracket 14 having separate passages 14a for each arm 13, as shown in Fig. 4, allow-ing the width of the ~aP between the channels 11c,11c on the two sections 11a, 11b to be ad~iusted in order to accommodate differ-ent sized driP chambers 23. The whole outer housing assembly 11 can be constructed from a relatively soft, resilient plastic which would allow arms 13 and brackets 14 to have an easily slidable friction fit.
Recharger contacts 18 and battery door 17. shown in Figs. 3 and 5. are provided on the side and on the bottom of housing section 11a. Also included on the housing 11 are 5 or more DIP
(Dual Inline Packaqe) switches 34 that ad~just the alert period between drops 24 in the drip chamber 23. and an on-off switch 39.
To connect the various components in the two housin~s 11a,11b a connecting line(not shown) would be sent throu~h or ad~iacent to the arm 13 and bracket 14 assemblY. The alarm system 10 is small enough to fit within a normal shirt pocket, bein~ no more than 4 inches by 2 1/8 inches by 7/8 inches thick.
The photovoltaic cell is shown in Fi~s. 1, 2, 3 and 6. The cell consists of a singular emitter 21 and receiver 22 spaced opposite each other in the channels 11c of sections 11a and 11b.
The sPecific device used to emit is an infrared diode 21 which emits a beam of infrared light through a clear I.V. drip chamber 23 to an infrared detector 22. The advanta~e of usin~ infrared li~ht instead of visible light is that there will be less inter-ference from the outside visible light sources around the device.
The receiver 22 receives a constant si~nal from the emitter 21 until a droP 24 intercepts the path between emitter 21 and re-ceiver 22. The interDosing of the drop 24 between the emitter diode 21 and the receiver 22 changes the receiver's incomin~
si~nal. The receiver 22 is constantly sending out a signal to the alarm circuitry. This receiver output is chan~ed accordingly and causes a reaction in the alarm circuitry as will be detailed below.
The alarm circuitry contains a power source for the whole device. Nickel-cadmium batteries ~0 of 7.2 volt type are used because of their long life. These types of batteries are also easily rechargeable. hence the rechargin~ ports 18 consistin~ of a common DC port connectable to a conventional batterY recharger 54 which is operable to rechar~e batteries 50 only when on-off switch 59 is in the off position and the alarm system is not being used~ as is well known in the battery recharging art.
These batteries 50 should keeP the alarm device functional for about 5 hours as the device has low power requirements with CMOS
~circuitry.
Fiq. 6 shows the circuit diagram for the device. Sensor blocl; 31 consists of an emitter and receiver 21.22. A voltaqe comparator 32 is constantlY checking for voltage fluctuations.
If it detects one, a signal uulse is sent to a counter 33 (4541 type) which begins a countinq sequence. Should another pulse be sent bY the comparator 32. the counter 33 will be retriggered to start at the beginnin~. A five-position DIP switch 34, also shown in Fig. 3, allows the user to set the maximum drop delay time for the counter 33. Should the counter 33 reach this maxi-mum delaY count without beinq retriggered bY a comparator Pulse~
the counter 33 outPuts a Pulse to an AF (Audio Frequency~ 1/2 556C tYpe) oscillator 35, which will in turn output a pulse to an astable modulating oscillator (1~2 556C tYpe) 36. The modulating oscillator 36 is connected to a Piezo audio transducer or speaker 37 which produces the alarm sound. The two oscillators 35~36 are capable of producin~ a variety of sounds. A modulated single tone ~on-off-on-off)~ a modulated dual tone (hi~h-low-high-low) or an unmodulated sin~le tone. The type of tone can be selected by the user of the device 10.
A low power visual alarm LED 38 is connectQd to the outPut of another CMOS timer/multivibrator 52 (555C type) similar to oscillator 36 which is also controlled by the reset pulse of the driP sensing comparator 32. Oscillator timings of 100 ms are good for viewin~. Reset switch 12 would send a pulse back to the 2 ~ J ~l counter 33 to retri~qer its sequence separately of the voltage comparator 32.
In use the maximum desired delay time is about 20 seconds.
The five-position DIP switch 34 can select a range between 20 seconds and zero time between droPs in the I.V. chamber 23. The DIP switch 34 could have a variable amount of positions. Five are taken as a good sampling of driP times.
It is to be understood that the Present invention is not limited to the sole embodiment described above, but encompasses any and all embodiments within the scoPe of the following claims.
Claims (10)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. An intravenous alert system comprising:
infrared photovoltaic drop sensing means, placed on either side of an intravenous drip chamber to detect drops as they Pass by;
comparator means to detect a change in an output voltage that is sent by said drop sensing means, said comparator means sending a trigger signal when said drop sensing means detects a drop;
counter means to time the interval between drops in said drip chamber, said counter means receiving and being restarted by each new trigger signal from said comparator means, said counter means sending a signal when said counter means reaches a prede-termined value;
audio frequency oscillator means to receive said signal from said counter means, said audio frequency oscillator means sending out an audio frequency oscillator signal upon receiving said signal from said counter means;
astable modulating oscillator means to receive said audio frequency oscillator signal from said audio frequency oscillator means, said astable modulating oscillator means sending an as-table modulated oscillator signal;
audio alarm means to receive said astable modulated oscillator signal and to signal discontinuance of intravenous dripping;
containment means for said drop sensing means, comparator means, counter means, audio frequency oscillator means, astable modulating oscillator means and said alarm means;
power means to provide current to said intravenous alert system:
switch means to switch said Power means on or off: and CMOS circuitry being used to construct said comparator means, counter means, audio frequency oscillator means and astable modulating oscillator means, said CMOS circuitry provid-ing a small size to the intravenous alert system allowing ease of use and portability.
infrared photovoltaic drop sensing means, placed on either side of an intravenous drip chamber to detect drops as they Pass by;
comparator means to detect a change in an output voltage that is sent by said drop sensing means, said comparator means sending a trigger signal when said drop sensing means detects a drop;
counter means to time the interval between drops in said drip chamber, said counter means receiving and being restarted by each new trigger signal from said comparator means, said counter means sending a signal when said counter means reaches a prede-termined value;
audio frequency oscillator means to receive said signal from said counter means, said audio frequency oscillator means sending out an audio frequency oscillator signal upon receiving said signal from said counter means;
astable modulating oscillator means to receive said audio frequency oscillator signal from said audio frequency oscillator means, said astable modulating oscillator means sending an as-table modulated oscillator signal;
audio alarm means to receive said astable modulated oscillator signal and to signal discontinuance of intravenous dripping;
containment means for said drop sensing means, comparator means, counter means, audio frequency oscillator means, astable modulating oscillator means and said alarm means;
power means to provide current to said intravenous alert system:
switch means to switch said Power means on or off: and CMOS circuitry being used to construct said comparator means, counter means, audio frequency oscillator means and astable modulating oscillator means, said CMOS circuitry provid-ing a small size to the intravenous alert system allowing ease of use and portability.
2. The intravenous alert system according to Claim 1, including:
recharger means connected to said power means, when said power means is switched off by said switch means! to recharge said Power means,
recharger means connected to said power means, when said power means is switched off by said switch means! to recharge said Power means,
3. The intravenous alert system according to Claim 1, wherein:
said infrared photovoltaic drop sensing means comprises an infrared emitter and an infrared receiver,
said infrared photovoltaic drop sensing means comprises an infrared emitter and an infrared receiver,
4. The intravenous alert system according to Claim 1, including:
visual alarm means connected to said astable, modulating oscillator means.
visual alarm means connected to said astable, modulating oscillator means.
5. The intravenous alert system according to Claim 1, wherein:
said predetermined value is able to be varied by a means to vary operation by the user of said intravenous alert system.
said predetermined value is able to be varied by a means to vary operation by the user of said intravenous alert system.
6. The intravenous alert system according to Claim 5. wherein:
said means to vary said predetermined value are a series of DIP switches located on said containment means.
said means to vary said predetermined value are a series of DIP switches located on said containment means.
7. The intravenous alert system according to Claim 1. wherein:
said audio alarm means is a piezo audio transducer.
said audio alarm means is a piezo audio transducer.
8. The intravenous alert system according to Claim 4 wherein:
said visual alarm means is an LED.
said visual alarm means is an LED.
9. The intravenous alert system according to Claim 1 wherein:
said containment means comprises two separate sections disposed on opposite sides of said drip chamber said sections are connected by at least one elongated arm on one of said sections being disposed through a receiving slot on the other of said sections. said arm and slot being laterally offset from said sections and said drip chamber and having a sliding adjustable fit to accommodate various sized drip chambers.
said containment means comprises two separate sections disposed on opposite sides of said drip chamber said sections are connected by at least one elongated arm on one of said sections being disposed through a receiving slot on the other of said sections. said arm and slot being laterally offset from said sections and said drip chamber and having a sliding adjustable fit to accommodate various sized drip chambers.
10. The intravenous alert system according to Claim 9 wherein:
each said section has a semi-cylindrical channel on a side of each said section. said semi-cylindrical channels are disposed opposite each other such that an I.V. drip chamber can be disposed therebetween.
each said section has a semi-cylindrical channel on a side of each said section. said semi-cylindrical channels are disposed opposite each other such that an I.V. drip chamber can be disposed therebetween.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA002061154A CA2061154A1 (en) | 1992-02-13 | 1992-02-13 | I.v. alert system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA002061154A CA2061154A1 (en) | 1992-02-13 | 1992-02-13 | I.v. alert system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2061154A1 true CA2061154A1 (en) | 1993-08-14 |
Family
ID=4149248
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002061154A Abandoned CA2061154A1 (en) | 1992-02-13 | 1992-02-13 | I.v. alert system |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA2061154A1 (en) |
-
1992
- 1992-02-13 CA CA002061154A patent/CA2061154A1/en not_active Abandoned
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Discontinued | ||
| FZDE | Discontinued |
Effective date: 19950813 |