System for monitoring trash compactors

1 2

location deactivates the trash container and activates a SYSTEM FOR MONITORING TRASH trash compactor having an empty container.

COMPACTORS Another such system sold and used heretofore in

cludes compactor controllers manufactured by PetroCROSS-REFERENCE TO RELATED 5 Vend, Inc., for Waste Management, Inc. In that system,

APPLICATION a compactor controller including a microprocessor at

This application is a continuation-in-part of U.S. pa- eac* tTasl\ comPacftor is TMSed for HTMting ac_cess t0

tent application Ser. No. 07/959,709 filed Oct. 13, 1992 authorized users, for monitoring usage of such trash

(pending), and assigned commonly herewith. in compactor by each authorized user and by all autho

lu nzed users, for recording data concerning such usage,

TECHNICAL FIELD OF THE INVENTION and for transmitting data concerning such usage to a

This invention pertains to a system for monitoring, computer at a central location, via a modem and tele

from a computer at a remote, central location or from a phone connections.

r ■ -t J. J. ill ii Various embodiments of such a system are disclosed

facsimile machine at a remote, central location, a plural- i< ." , TT „ ~" ,n„" ,

■t . . , . - . • • ♦ v m Neumann et al. U.S. Pat. No. 5,016,197. In each em

lty of trash compactors of a type comprising a trash ... . • j' • t_ i_ * i_

„ t ■ „ i? bodiment, a sensmg unit associated with each trash

container, a ram operative m compacting strokes for A' .6 . , ^ .

_ ,• , ... iU „ . j . compactor transmits data to a computer at a central

compacting trash within the container, and means for , K . ^ , , .. _ v , ^

, . c . , , . , T »i. location, via telephone lines. The computer determines

applying force to advance and retract the ram. In the ... r , f , f *\. , .„ ,

, °,„ r. . f , * , fullness- of each trash compactor from the transmitted

system, fullness of the container of each trash compac- 20JiT t_j- , 1 , -^jj^-ij

/.' ■ . r r ■ ii.- i data. In one embodiment, the transmitted data include

tor is determined from a series of signals having values , . ,= * >. , t

, t. , r . . ,. data relating to instantaneous pressures and to actuation

representative of the sensed force at successive times e .. °.i , T iV r , ,. ^ ^ ,.

, r. . , . A, of a limit switch. In another embodiment, the transmit

dunng a compacting stroke, by comparing the maxi- ^jj.-ij r

° , ... ... ... ... i J ted data include sequences of instantaneous pressure

mum value to a threshold value. In one contemplated Jir i.- i_ + -i j . I r

, ,. x , . , . j. data, from which the computer compiles a database for

embodiment, the unit comprises a modem for sending a 25 ... ^ ctor ^ ^ determines fuli.

facsimile message to a remotely located facsimile ma- ngss ffom ^ ... fa Qther embodimentS) the trans.

chine when fullness of the container of a trash compac- mined data ... data rdati t0 ram work> cha

tor has been determined. • ^ . ^ ■

m pump motor current, or increases in container

BACKGROUND OF THE INVENTION 30 weight.

In shopping malls, office buildings, apartment build- SUMMARY OF THE INVENTION

ings, and other properties having multiple occupants, it BrQadl tWs invention ides a unit for monitoring

is common to provide a plurality of trash compactors of a {rash com actor of a type comprising a container, a

a type comprising a trash container, a hydraulic ram fam operative in compacting strokes for compacting

operative in compacting strokes for compacting trash tfash m the container> ^ means for appiying force to

wuhin the container, and a hydraulic pump operative drive the ram Broadly) the unit comprises means for

for advancing and retracting the ram in such manner sensing force app]ied t0 the ram during each compact.

that hydraulic pressure is capable of being sensed be- ing stroke and means for determining fullness of the

tween the pump and the ram. Frequently, arrangements ^ container by generating a series of signals having values

are made for a hauler to empty the containers of specific representative of the sensed force at successive times

ones of the trash compactors on a periodic basis, or during such compacting stroke, determining which

whenever the hauler is contacted by a manager. Com- generated value is the maximum generated value, and

monly, the hauler charges similar hauling fees whether comparing the maximum generated value to a threshold

the containers are filled partially or completely. There 4J vaiue indicative of fullness of the container. Preferably,

is a need, therefore, for managers of such properties to the threshold value is user-definable from a remote

receive current information concerning which of the computer. Herein, references to fullness are intended to

trash compactors require and do not require emptying. refer to empty, partially full, and completely full condi

As exemplified in Clar U.S. Pat. No. 3,336,861, Clar tions of the container.

U.S. Pat. No. 3,534,678, Woyden U.S. Pat. No. 50 Commonly, such a trash compactor comprises a con

3,636,863, and Brown U.S. Pat. No. 4,603,625, it is tainer, a hydraulic ram operative in compacting strokes

known to provide a trash compactor with pressure- for compacting trash within the container, and a hy

sensing or other means for determining when the con- draulic pump operative for applying hydraulic pressure

tainer of the trash compactor is full. The Woyden pa- to advance and retract the ram during each compacting

tent discloses an arrangement of such means wherein 55 stroke of the trash compactor. The sensing means may

telephone lines are used to send an alarm signal to a be then arranged for sensing hydraulic pressure be

central office when an abnormal condition is sensed. tween the pump and the ram during each compacting

Various systems have been disclosed for monitoring a stroke and for generating a frequency signal representa

plurality of trash compactors of the type noted above tive of the sensed pressure. Moreover, the fullness

from a central location. 60 determining means may be then arranged for determin

An early example of such a system is disclosed in ing fullness of the container by generating a series of

Budoff U.S. Pat. No. 4,044,664. In that system, each pressure signal values from the frequency signal, deter

trash compactor has a detector including a pressure mining which generated pressure signal value is the

switch for detecting increased pressure in the hydraulic maximum pressure signal value, and comparing the

fluid driving a hydraulic ram in such trash compactor 65 maximum pressure signal value to a threshold value,

when the container of such trash compactor has become The generated pressure signal values are representative

packed. Moreover, when the container of a trash com- of the sensed pressure at successive times during such

pactor becomes packed, a station selector at a central compacting stroke.

DETAILED DESCRIPTION OF ILLUSTRATED
EMBODIMENTS

3 4

Thus, the fullness-determining means may be advan- processor arranged-to receive pressure signals from the tageously arranged for comparing the maximum pres- transducer, and a modem, which is arranged to send sure signal value to a minimum threshold value indica- status signals to a remote computer, tive that the trash compactor has a substantially empty FIGS. 2A and 2B are respective sections of a logical container, determining that such compacting stroke 5 diagram showing various processing steps performed occurred with the trash compactor having a substan- by the microprocessor receiving pressure signals from tially empty container if the maximum pressure signal the transducer. Exemplary values, from a preferred value is less than the minimum threshold value in each embodiment, are indicated on the logical diagram, of a specified number of successive instances with a FIG. 3 is a schematic diagram of a system including a delay time of a specified duration between the first and 10 plurality of monitoring units similar to the monitoring second instances, comparing the maximum pressure unit of FIG. 1 for monitoring a plurality of trash comsignal value to a maximum threshold value indicative of pactors similar to the trash compactor of FIG. 1 from a the trash compactor having a substantially full con- remote, central computer arranged to receive status tainer if the maximum pressure signal value is not less signals from the microprocessors of such units, via the than the minimum threshold value, and determining 15 modems of such units.

that such compacting stroke occurred with the trash FIG. 4 is a schematic diagram of a trash compactor compactor having a substantially full container if the comprising a trash container, a hydraulic driver includmaximum pressure signal value is compared to and ing a cylinder and a ram, a hydraulic pump, and related exceeds the maximum threshold value. components, as associated with a monitoring unit ac

Also, the fullness-determining means may be advanta- 20 cording to a second embodiment of this invention. The geously arranged for generating a status signal when- monitoring unit includes a pressure transducer, a microever a specified number of compacting strokes with the processor arranged to receive pressure signals from the trash compactor having a substantially full container transducer, and a modem, which is arranged to send have been determined to have occurred, for generating facsimile messages to a remotely located facsimile maa status signal whenever a specified number of compact- 25 chine, ing strokes with the trash compactor having a substantially empty container have been determined to have occurred, or for both functions.

In a first embodiment of this invention, the unit may As shown diagrammatically in FIG. 1, a monitoring comprise -means for transmitting the status signal or 30 unit M according to a first embodiment of this invention status signals to a computer at remote location when the is combined with a trash compactor C of the type noted status signal or status signals are generated. above. The trash compactor C comprises a trash con

In a second embodiment of this invention, the unit tainer 10 and a hydraulic driver 12, which includes a comprises means for sending a facsimile message from ram 14 operative for compacting trash within the conthe unit to a facsimile machine at a remote location 35 tainer 10, and which includes a hydraulic cylinder 16. when the fullness-determining means has determined The cylinder 16 is arranged to receive hydraulic fluid at that the container of the trash compactor is substantially a first connection 18 for advancing the ram 14 relative full, as when a status signal indicating that the container to the container 10 and to receive hydraulic fluid at a of a trash compactor associated therewith is generated. second connection 20 for retracting the ram 14 relative

This invention also provides a system comprising a 40 to the container 10. plurality of the monitoring units noted above for moni- The trash compactor C also comprises a reservoir 22 toring a plurality of trash compactors of the type noted for hydraulic fluid, a shuttle valve 24, and a hydraulic above from a central computer. Each monitoring unit is pump 26. The shuttle valve 24 is operative selectively in associated with a respective one of the trash compac- a ram-advancing mode for directing hydraulic fluid tors. 45 from the pump 26 to the first connection 18 and for

In a system based on the first embodiment noted returning hydraulic fluid from the second connection 20 above, the system comprises means for sending the to the reservoir 22 and in a ram-retracting mode for status signals to a central computer at a remote location. directing hydraulic fluid from the pump 26 to the seeIn a system based on the second embodiment noted ond connection 20 and for returning hydraulic fluid above, the system comprises means for sending a fac- 50 from the first connection 18 to the reservoir 22. The simile message from each monitoring unit to a facsimile pump 26 is operative for receiving hydraulic fluid from machine at a remote location when the fullness-deter- the reservoir 22 and for directing hydraulic fluid to the mining means has determined that the container of the shuttle valve 24 so as to apply hydraulic pressure to the trash compactor is substantially full, as when a status ram 14, via the shuttle valve 24 and the cylinder 16. signal indicating that the container of a trash compactor 55 Thus, the pump 26 may be also considered as applying associated with such monitoring unit is generated. hydraulic force to the ram 14, via the shuttle valve 24

These and other objects, features, and advantages of and the cylinder 16. The trash container 10, the hydrauthis invention are evident from the following descrip- lie driver 12, the reservoir 22, the shuttle valve 24, the tion of a preferred embodiment of this invention with pump 26, and other components of the trash compactor reference to the accompanying drawings. 60 C may be conventional components, details of which

are outside the scope of this invention. The monitoring unit M comprises a pressure transFIG. 1 is a schematic diagram of a trash compactor ducer 30 arranged for sensing hydraulic pressure or comprising a trash container, a hydraulic driver includ- hydraulic force, as applied by the pump 26 to the ram ing a cylinder and a ram, a hydraulic pump, and related 65 12, via the shuttle valve 24 and the cylinder 16. The components, as associated with a monitoring unit ac- transducer 30 is connected to a hydraulic line between cording to a first embodiment of this invention. The the pump 26 and the shuttle valve 24. The pressure monitoring unit includes a pressure transducer, a micro- transducer 30 is connected to the hydraulic line in a

BRIEF DESCRIPTION OF THE DRAWINGS

7 8

If the microprocessor 40 determines that the maxi- preferably plural, three as an example. The micromum pressure value is less than the minimum threshold processor 40 takes no action if it determines that the full pressure, the microprocessor 40 determines whether the compaction count is less than the full compaction time delay defined by the time delay counter is over and threshold number.

takes no action if it determines that the time delay is not 5 If the microprocessor 40 determines that the full cornover. Effectively, the microprocessor 40 takes no action paction count equals the full compaction threshold unless it determines that the maximum pressure value is number, the microprocessor 40 determines and generless than the minimum threshold pressure, in each of a ates a status signal indicating that the container of the specified number of successive instances with a time trash compactor is substantially full and transmits the delay of a specified duration between the first and sec- 10 status signal to the remote computer 42, via the modem ond instances. The time delay is a short delay, three 44 and telephone connections.

seconds as an example, which is defined by a user enter- Since a single value may represent an abnormal coning parameters into the microprocessor 40. The time dition, it is preferred for the full compaction threshold delay is intended to avert a false determination by the number to be a plural number, whereby a determination microprocessor 40 that an empty compaction has oc- 15 by the microprocessor 40 that the container of the trash curred from the hydraulic pressure that is sensed just as compactor is substantially full tends to be more reliable the ram 14 begins to advance. than the determination would be if the full compaction

If the microprocessor 40 determines that the time threshold number were one.

delay is over after determining that the maximum pres- A user enters certain parameters noted above into the

sure value is less than the minimum threshold pressure, 20 microprocessor 40, from the remote computer 42,

the microprocessor 40 increments an empty compaction namely the reference pressure value, the minimum

count by one. Whenever the empty compaction count is threshold pressure value, the duration of the time delay,

incremented, the microprocessor 40 compares the the empty compaction threshold number, the maximum

empty compaction count to an empty compaction threshold pressure value, and the full compaction

threshold number, which is defined by a user entering 25 threshold number. It may be then necessary for the user

parameters into the microprocessor 40. Preferably, the to enter, for each microprocessor 40, different parame

empty compaction threshold number is a plural number, ters appropriate for the trash compactor C associated

two as an example. If the microprocessor 40 determines with such microprocessor 40. When the microprocessor

that the empty compaction count is less than the empty 40 is initialized, the maximum pressure value recorded

compaction threshold number, the microprocessor 40 30 by the microprocessor 40 is set initially to a null value,

takes no action, except that the microprocessor 40 resets and the reading, compaction, empty compaction, and

the time delay. full compaction counts are set initially to zero.

If the microprocessor 40 determines that the empty The microprocessor 40 is programmed to perform its compaction count equals the empty compaction thresh- various functions noted above. Moreover, the microold number, the microprocessor 40 determines and gen- 35 processor 40 and the computer 42 may be also proerates a status signal indicating that the container of the grammed to enable the computer 42 to poll the microtrash compactor is substantially empty. Also, the micro- processor 42 at any time for data, such as the maximum processor 40 transmits the status signal to the remote pressure value and the compaction count, computer 42, via the modem 44 and telephone connec- As shown in FIG. 3, such a computer 42 may be tions. 40 advantageously used as a remote, central computer in a

Since a single value may represent an abnormal con- system for monitoring a plurality of such trash compac

dition, it is preferred for the empty compaction thresh- tors C, each being associated with such a monitoring

old number to be a plural number, whereby a determi- unit M comprising such a pressure transducer 30, such a

nation by the microprocessor 40 that the container of microprocessor 40, and such a modem 44, as described

the trash compactor is substantially empty tends to be 45 above.

more reliable than the determination would be if the In a second embodiment of this invention, as illus

empty compaction threshold number were one. trated in FIG. 4, a monitoring unit M according to a

If the microprocessor 40 determines that the -maxi- second embodiment of this invention is combined with

mum pressure value is not less than the minimum a trash compactor C of the type noted above. Except as

threshold pressure value, the microprocessor 40 com- 50 illustrated in the drawings and described herein, the

pares the maximum pressure value to a maximum second embodiment of this invention is similar to the

threshold pressure value. The microprocessor 40 takes first embodiment of this invention and operates simi

no action if it determines that the maximum pressure larly, particularly as to the microprocessor 40 determin

value is not more than the maximum threshold pressure ing and generating a status signal indicating that the

value. As defined by a user entering parameters into the 55 container 10 of the trash compactor is substantially full,

microprocessor 40, the maximum threshold is a rela- In the second embodiment illustrated in FIG. 4, the

lively high pressure value, 1000 psig as an example, modem 44 is a facsimile modem, which is capable of

above which the container 10 of the trash compactor C sending facsimile messages over ordinary telephone

is considered to be substantially full. lines to a conventional, remotely located, facsimile ma

If the microprocessor 40 determines that the maxi- 60 chine 46. The remote computer 42 is used to download

mum pressure value is more than the maximum thresh- a facsimile image, as a file, to the microprocessor 40.

old pressure value, the microprocessor 40 increments a The microprocessor 40 stores the facsimile image, as a

full compaction count by one. After the full compaction file, until the -microprocessor 140 is commanded to

count has been incremented, the microprocessor 40 send a facsimile message corresponding to the facsimile

compares the full compaction count to a full compac- 65 image to the facsimile machine 46.

tion threshold number, which is defined by a user enter- For use in the second embodiment, a modem suitable

ing parameters into the microprocessor 40. The full for the modem 44 is a VIVA Tm Model 2496if Modem

compaction threshold number is a counting number, available commercially from Computer Peripherals,