WO2009115514A1

WO2009115514A1 - Refuse control system for refuse chutes

Info

Publication number: WO2009115514A1
Application number: PCT/EP2009/053131
Authority: WO
Inventors: David Culleré Vidal
Original assignee: Ros Roca, S. A.
Priority date: 2008-03-17
Filing date: 2009-03-17
Publication date: 2009-09-24
Also published as: PT2268561T; EP2268561A1; ES2838149T3; EP2268561B1

Abstract

It comprises sensing means (100; 200) for detecting each time a refuse package (10) is passed within a refuse chute (20), counting means for providing a count on the number of refuse packages (10) that have been passed through said portion (25) and actuation means for sending a command for emptying the refuse chute (20) when a predetermined number of refuse packages (10) is present within said refuse chute (20). Sensing means may be a mechanical sensor (100) which can be moved by packages (10) passing through said portion (25), or signal emitting and detecting means (210, 220).

Description

Refuse control system for refuse chutes

Field of the invention

The present invention relates to a refuse control system that is intended to be applied to refuse chutes in a refuse collection system. Refuse chutes are adapted for receiving waste products therein in packages such as refuse bags or the like. Waste products may be, for example, inorganic refuse, organic refuse and the like.

The main object of the refuse control system of the invention is to determine the volume of refuse inside the corresponding refuse chute, i.e., counting the refuse packages that are present therein. When a certain value of the volume of refuse inside a particular refuse chute is reached, said refuse chute is caused to be emptied. Detection of volume of refuse within a refuse chute is carried out by sensing means adapted for detecting each time a refuse package is successively passed through a sensing portion within the refuse chute. Counting means, such as a counter device, may be used for providing a count on the number of refuse packages that have been passed through said sensing portion of the refuse chute.

The invention further relates to a method for controlling the volume of refuse that is present within a refuse chute.

BACKGROUND ART

Refuse collection systems typically comprise a number of refuse chutes arranged in a network where refuse is to be selectively disposed. Refuse chutes are each connected to waste pipes leading to a common transport pipe system through corresponding discharge valves. Waste products are driven by a transport pipe system (for example by an air stream, usually at vacuum conditions) that drives them to at least one collection station for treating, recycling, disposal, etc.

Discharge valves associated with each refuse chute at a lower portion thereof are provided. Such valves can be actuated for emptying a corresponding refuse chute (that is, discharging the refuse packages into the collection station) when said refuse chute is considered to be full, that is, when a certain volume of refuse (a given number of refuse packages) is detected within the corresponding refuse.

Detection of the volume of refuse (number of refuse packages) within a particular refuse chute is carried out typically by using level sensor devices that are associated to each refuse chute such that a level indication signal can be sent to actuation means for opening the corresponding discharge valve when the refuse chute is considered to be full.

Examples of sensor means used for this purpose are disclosed in GB2282956 and EP1482285. The sensor means in GB'956 comprise an impulse reflection level sensor (ultrasound or piezoelectric transducer) which detects the distance from the sensor (at the top of the refuse container) to the refuse (after each deposit, or constantly at a specific time interval) that heaps within the container. A level indication signal is sent to a actuation means and from there to transport vehicle. The sensor means disclosed in EP'285 is an ultrasonic sensor for real time measuring of refuse level within a refuse container.

GB2321518 provides a refuse receptacle inside of which sensing means for sensing the introduction of an object into the receptacle are provided. The sensing means comprise two light emitters and corresponding light detectors. Emitters cooperate with two mirrors reflecting the emitted light back and forth creating upper and lower webs of radiation, the obstruction of which are determined when the object is passed.

None of the above disclosed prior art sensor means is adapted for causing refuse chutes in a refuse chute network of a waste disposal system to be emptied when a particular refuse chute contains a given number of refuse packages.

SUMMARY OF THE INVENTION

The present invention provides a control system for refuse chutes in a refuse collection system. The refuse control system comprises sensing means for detecting each time a refuse package is successively passed through an inner sensing portion in the refuse chute and counting means for providing a count on the number of refuse packages that have been passed through said sensing portion of the refuse chute.

The term "package" as used herein stands for any covering wrapper or container inside of which waste is received, such as for example a waste plastic bag or the like. The term "waste" as used herein stands for any inorganic material (paper, plastics, metals, rubber, leather, textiles), organic material (food scraps, wood, and household refuse containing organic matter) and the like.

For emptying the refuse chutes in a refuse collection system it is useful to know the volume of refuse that is present inside the refuse chute, above the refuse discharge valve. For this purpose, the refuse control system of the invention further includes actuation means adapted for causing the refuse chute to be at least partially emptied based on said count of refuse packages within the refuse chute. Emptying of the particular refuse chute is carried out b said actuation means by sending a command for operating the corresponding discharge valve associated with said refuse chute for causing it to be emptied (i.e. discharging the refuse packages received within) when a predetermined number of refuse packages is found to be present within said refuse chute.

In a first embodiment of the invention, the sensing means may comprise a movable arm (e.g. a pivotable lever) arranged in the sensing portion within the refuse chute. This arm may be arranged such that it can be moved (i.e. rotated) by refuse every time a refuse package is successively passed through said refuse chute sensing portion. As the movable arm is rotated by a refuse package, a switch associated therewith is activated thus causing the presence of refuse to be detected and said count to be increased (for each cycle of rotational movement of the arm). When the count reaches a maximum value, a command is sent by the actuation means for emptying the refuse chute concerned. The length of the arm may be varied depending on the desired resolution for the sensing means. Longer arms may be preferred particularly in great height refuse chutes as the signal becomes amplified as the time during which the refuse package is passed through the refuse chute inner sensing portion is increased. In a second embodiment, the sensing means may comprise signal emitting means and signal detecting means. The emitting means may be adapted for emitting a signal through a sensing portion within the refuse chute such that when refuse is successively passed therethrough the signal is interrupted during a period of time causing the presence of refuse to be detected and said count to be increased. As in the first embodiment, when a maximum value of the count is reached, a command is sent by the actuation means for emptying the refuse chute concerned.

In this second embodiment, both the emitting and the sensing means operate with either ultrasound or light signals although other types of signals can be used provided they can be managed by communications modules.

In any case, the signal emitting and sensing means may be provided either substantially in line to each other or arranged such that a line mutually joining the signal emitting and sensing means forms an angle to the horizontal, for example ranging from 0 to 60 degrees, with 45 degrees being preferred. The angled arrangement of the sensing means is preferred particularly in great height refuse chutes since the signal to be detected by the sensing means is amplified as the signal interrupt time is increased. "Signal interrupt time" as used herein refers to the period of time during which the signal is interrupted as the refuse package is passing through the refuse chute sensing portion. The increase in the signal interrupt time involves a higher resolution sensing means.

The signal emitting and sensing means may be located distant to each other, e. g. in opposite locations in the refuse chute cross-section, or they may be arranged proximate to each other. In the latter case (both emitting and sensing means arranged proximate to each other) reflexive sensors may be used in which light is emitted bouncing on the refuse package. In this case, the emitting means and the sensing means are formed in a single assembly.

Electronic circuitry (such as a RC circuit) may be provided for increasing the signal interrupt time in such an extent that they can be read by a communications modules or PLC. The RC circuit may be adapted for causing signal interrupt time becomes longer to be efficiently measured by control electronics.

With the control system of the invention the number of refuse packages within a refuse chute can be determined and consequently the volume percentage occupied by the refuse packages therein. The volume inside the refuse chute can be precisely known from the number of the refuse packages and the size of each of said refuse packages. In addition, the size of each refuse package that is disposed within the refuse chute can be determined as well.

The invention further relates to a method for controlling the volume of refuse that is present within a refuse chute consisting in detecting each time a refuse package is successively passed through a sensing portion within the refuse chute by sensing means; increasing a count through a counting means concerning the number of refuse packages that have been passed through said sensing portion and sending a command for causing the refuse chute to be at least partially emptied based on said count of refuse packages within the refuse chute.

BRIEF DESCRIPTION OF THE DRAWINGS

A particular embodiment of a refuse control system for refuse chutes according to the present invention will be described in the following, only by way of non-limiting example, with reference to the appended drawings, in which:

Fig. 1 is an elevational fragmentary view of a first embodiment of the sensing means in a control system of the invention fitted in a refuse chute;

Fig. 2 is an elevational fragmentary view similar to Fig. 1 in which a second embodiment of the sensing means are shown in which reflexive cell sensors are provided; and

Fig. 3 is an elevational fragmentary view similar to Fig. 2 showing a second embodiment of the sensing means shown in which an angled sensor arrangement is provided. DETAILED DESCRIPTION OF PARTICULAR EMBODIMENTS

A refuse chute 20 comprises a tubular body provided with an inlet upper opening 21 through which refuse packages 10 are disposed into the refuse chute 20. The refuse chute 20 has a discharge valve 30 at the bottom portion thereof suitable for emptying the refuse packages 10 therein when a certain volume percentage is being taken up by the refuse packages 10 in the refuse chute 20. A control system is further provided having sensing means 100; 200 associated with each refuse chute 20, several embodiments of which are disclosed in the figures.

The purpose of the sensing means 100; 200 associated with each refuse chute 20 is detecting each time a refuse package 10 is successively passed through an inner sensing portion 25 within the refuse chute 20. The refuse control system further comprises counting means for providing a count on the number of refuse packages 10 that have been passed through said sensing portion 25 of the refuse chute 20 over a given period of time.

Counting of the refuse packages 10 inside a refuse chute 20 is useful for determining the volume of refuse that is present inside a particular refuse chute 20, above the refuse discharge valve 30. For this purpose, actuation means are also provided suitable for sending a command for operating the discharge valve 30 and causing said refuse chute 20 to be emptied. This occurs when the count is found by the actuation means to be equal to a preset number of refuse packages 10.

In a first embodiment of the sensing means 100 shown in Fig. 1 , they comprise a pivotable lever 110 arranged in said sensing portion 25 within the refuse chute 20. The pivotable lever 110 is arranged such that it can be rotated as refuse packages 10 are falling down within the refuse chute 20 passing successively through said refuse chute sensing portion 25 where the lever 110 is arranged. Rotation of the pivotable lever 110 (as shown in two different angular positions in Fig. 1 ) causes a switch associated therewith (not shown) to be actuated. Each time the switch is actuated by rotation of the pivotable lever 110 as one refuse package 10 is passed therethrough the count is increased by one unit. When said count associated with said refuse chute 20 reaches a value matching a preset maximum value, said particular refuse chute 20 is considered by the actuation means as ready to be emptied and therefore a command is sent by the actuation means for emptying said refuse chute 20.

Signal interrupt time t is herein defined as the time taken by refuse package 10 for traveling a distance D between two defined points D1 , D2 in the same refuse package 10 but in two different moments, as shown in Fig. 1 : a first moment when the refuse package 10 just before passing through the sensing means 100 and a second moment when said refuse package 10 has just left passing through the sensing means 100.

In the embodiment herein disclosed, the pivotable lever 110 is in the form of a rotatable bar the length L of which may be varied depending on the desired resolution for the sensing means 100. Longer pivotable levers 110 may be preferred particularly in refuse chutes 20 of great height H. In the following, H will be used for indicating the distance between the point from which the refuse packages 10 are disposed into the refuse chute 20 (i.e. upper inlet 21 ) and the upper portion of the discharge valve 30 at the bottom of the refuse chute 20. A longer lever 110 will be rotated during a longer period of time as the particular refuse package 10 is falling down. This will result in an amplified output signal as the time during which the refuse package 20 is passed through the refuse chute inner sensing portion 25 will be increased.

In a second embodiment of the sensing means 200 shown in Fig. 2, they comprise signal emitting means 210 for emitting a signal to a signal detecting means 220 through a sensing portion 25 within the refuse chute 20. When a refuse package 10 is successively passed through that sensing portion 25 within the refuse chute 20, the signal is interrupted during a signal interrupt time t as said refuse package 10 is passing. This causes the count to be increased. As in the first embodiment, when the count has a value matching a preset value, a command is sent by the actuation means to the discharge valve 30 associated with said particular refuse chute 20 for emptying it.

In this second embodiment, both the emitting and the sensing means 210, 220 operate with light signals. However, other types of signals can be used provided that can read by communications modules, such as ultrasound signals. In said Fig. 2 embodiment, the signal emitting and sensing means 210, 220 are provided substantially in line to each other (see line indicated at m,n in said Fig. 2). However, an angled arrangement such as shown in Fig. 3 may be preferred, that is, with both signal emitting and sensing means 210, 220 arranged at an angle α to each other, for example 45 degrees to the horizontal. The angled arrangement of the sensing means as shown in Fig. 3 is preferred for great height refuse chutes as the signal to be sent and detected by the emitting and sensing means 210, 220 is amplified as the signal interrupt time t is increased and therefore the sensing means 200 have a higher resolution. Said signal interrupt time t may range from 0.02 s to 0.1 s depending on the height h (in the example of Figs. Being of the order of 900 mm). In the following, h will be used for indicating the distance between the point from which the refuse packages 10 are disposed into the refuse chute 20 (upper inlet 21 ) and the sensing means 200. One example of said signal emitting and sensing means 210, 220 could be barrier photocells, optoelectric or reflexive cell sensors.

In this embodiment, the signal interrupt time t is defined as above, that is the time taken by refuse package 10 for traveling a distance D between two defined points D1 , D2 in the same refuse package 10 but in two different moments, that is, with D1 corresponding to a first moment when the refuse package 10 just before passing through the sensing means 200 and with D2 corresponding to a second moment when said refuse package 10 has just left passing through the sensing means 200. The signal interrupt time t can be further defined as the time during which the signal is interfered (i.e. interrupted) by the refuse package 10.

The signal emitting and sensing means 210, 220 may be located distant to each other, e. g. in opposite locations in the cross-section of the refuse chute inner sensing portion 25 as shown in the embodiments in Figs. 2 and 3. Although not shown in the drawings, the signal emitting and sensing means 210, 220 may be alternatively arranged proximate to each other in which case reflexive type sensors are preferably used where light is emitted on the refuse package 10 bouncing thereon, with both the emitting means 210 and the sensing means 220 being arranged proximate to each other forming a single assembly. In order to allow signal interrupt time t to be read by a communications module, electronic circuitry (such as a RC circuit -not shown-) may be provided for increasing said signal interrupt time t so that they can be read more accurately by, for example, a PLC.

An idea of the magnitude of signal interrupt time t could be as follows: for example, in the case in which the height h (distance from the sensing means 200 to the inlet upper opening 21 where the refuse package is dropped down) is 1 m, a 30 I refuse package 10 will actuate the sensing means 200 for about 0,067 s while a 50 I refuse package 10 will actuate the sensing means 200 for about 0,082 s. If a 45° angled sensing means 200 arrangement is used, signal interrupt times t will be longer: the 30 I refuse package 10 will actuate the sensing means 200 during about 0,092 s while the 50 I refuse package 10 will actuate the sensing means 200 during about 0,106 s. If a mechanical sensor (e.g. pivotable lever 110) is used, signal interrupt times t will be still longer: the 30 I refuse package 10 will actuate the pivotable lever 110 for about 0,138 s while the 50 I refuse package 10 will actuate the pivotable lever 110 for about 0,152 s.

The most preferred embodiment of the sensing means 200 could comprise barrier optical sensors with the line m joining signal emitting and sensing means 210, 220 at an angle α to the horizontal n. A value of 45 degrees is preferred for said angle α. This makes the signal interrupt time t to be longer (increased by about 41 %).

The greater the angle α is, and/or the bigger each refuse package 10 is, the longer the signal interrupt time t would be. Apart from this, the height h from which the refuse packages 10 fall down into the refuse chute 20 is taken into account by the refuse control system of the invention. Fall speed v of a body 10 varies with the height h and it is increased according to:

V²= 2-a-h

with h being the distance from the inlet opening 21 (from which a refuse package 10 is disposed into the refuse chute 20) to the sensing means 100; 200; and a being the acceleration of gravity. Therefore, signal interrupt time t is as follows:

wherein b is the size (diameter) of the refuse package 10. The height h and the angle α associated with the sensing means 100; 200 are both constant in a refuse chute 20.

The value corresponding to the signal interrupt time t is given by the actuation means. With these three parameters (α, h, t) the refuse package size b can be determined as follows:

b = (2 - a - h)^υ2 - t + - - a - t²

which derives from the equation V²= 2-a-h above and the equation of the uniformly accelerated motion x=x_o+v-t+1/2-a-t² wherein x-x_o=b and with B being the real refuse package size.

Furthermore, cos α= b/B and therefore B= cos-α-b.

The above calculations are the same when reflexive cell sensors are used as sensing means 200. In this particular case, the cell inclination given by α has the same effect on the refuse package size b. The package fall speed v is also the same when using reflexive cell sensors.

Similar calculations for determining the refuse package size b can be made in the event of using a mechanical sensor 100 such as the pivotable lever 110 in Fig. 1. In this case, the signal interrupt time t depends on the refuse package size b, the lever length L and the refuse package fall speed v determined as above by v²⁼ 2-a-h.

The real reuse package size B can be determined from the following formulae: -L² + R² + b²

B =

L + b h = - - a - t²

2

wherein L is the lever length and R is the radius of the refuse chute 20.

These calculations have been provided herein only as theoretical such that for example no package-air-chute coefficients of friction as well as package weight have been taken into consideration.

For example, given refuse chutes 10 of 500 mm in diameter and H= 2 m (with H being the height from inlet upper opening 21 to top portion of the discharge valve 30), there will be ten 30 I refuse packages 10 (that is, household-size packages 10 of 32x30x32 cm when full) involving 300 liters of refuse within the refuse chute 20. For 50 I refuse packages 10 (such as those used in restaurants, shops, etc. of 46x37x50 cm when full) there will be five of such refuse packages 10 involving 250 liters of refuse within the refuse chute 20. Of course, other sizes (such as 20 I, for the refuse packages 10 used in supermarkets, etc) could be measured within a refuse chute 20.

With these sizes B and the height H from which the refuse packages 10 are dropped into the refuse chute 20 (for example, 2 m herein) the number of refuse packages 10 within a refuse chute 20 can be precisely and effectively determined by the present refuse control system. Consequently, the volume percentage occupied by the refuse packages 10 within a refuse chute 20 can be determined as well as the size b of each refuse package 10 disposed therein.

The number of refuse packages 10 is compared by the refuse control system with a preset number of refuse packages 10 such that when a package count matches with a preset count representing a full refuse chute, an output signal is sent for causing the corresponding discharge valve 30 to be operated for emptying the respective refuse chute 20.

Claims

1 - Refuse control system for refuse chutes (20) that comprises sensing means (100; 200) for detecting each time a refuse package (10) is successively passed through a sensing portion (25) within the refuse chute (20), counting means for providing a count on the number of refuse packages (10) that have been passed through said sensing portion (25), and actuation means for causing the refuse chute (20) to be at least partially emptied based on said count of refuse packages (10) within the refuse chute (20), characterized in that said signal detecting means (220) are at an angle (α) to the signal emitting means (210).

2- Refuse control system as claimed in claim 1 , wherein said angle (α) lies in the range of 0 to 60 degrees.

3- Refuse control system as claimed in claim 1 or claim 2, wherein the sensing means (200) comprise signal emitting means (210) and signal detecting means (220), said emitting means (210) being adapted for emitting a signal through said sensing portion (25) within the refuse chute (20) such that when refuse packages (10) are successively passed therethrough the signal is interrupted causing the presence of a refuse package (10) to be detected and count to be increased.

4- Refuse control system as claimed in any of the preceding claims, wherein said signal emitting and sensing means (210, 220) are distant to each other.

5- Refuse control system as claimed in any of the claims 1 to 3, wherein said signal emitting and sensing means (210, 220) are proximate to each other.

6- Refuse control system as claimed in any of the preceding claims, wherein the signal is an optical signal.

7- Refuse control system as claimed in any of the preceding claims, wherein the signal is an ultrasound signal.

8- Refuse control system as claimed in claim 1 , wherein the actuation means further include signal relay means. 9- Refuse control system as claimed in claim 1 or claim 2, wherein the sensing means (100) comprise a pivotable lever (110) arranged in said sensing portion (25) such that it can be moved every time a refuse package (10) is successively passed through said refuse chute inner sensing portion (25) thus causing the presence of refuse to be detected and said count to be increased.

10- Refuse control system as claimed in claim 1 , wherein the actuation means are adapted to determine the size (b) of each refuse package (10) that is disposed within a refuse chute (20).

11 - A method for controlling the volume of refuse that is present within a refuse chute (20) comprising the steps of:

a) detecting each time a refuse package (10) is successively passed through a sensing portion (25) within said refuse chute (20) by sensing means (100; 200); b) increasing a count through a counting means concerning the number of refuse packages (10) that have been passed through said sensing portion

(25) and determining the volume of refuse inside the corresponding refuse chute (20); and c) sending a command for causing the refuse chute (20) to be at least partially emptied based on said volume of refuse within the refuse chute (20).