EP0234652B1

EP0234652B1 - Automatic water transfer installation for the equipment used to wash the refuse bodies

Info

Publication number: EP0234652B1
Application number: EP87200249A
Authority: EP
Inventors: Mario Cataldo
Original assignee: Calabrese Veicoli Industriali SpA
Current assignee: CALABRESE VEICOLI INDUSTRIALI S.P.A.
Priority date: 1986-02-24
Filing date: 1987-02-17
Publication date: 1990-07-25
Anticipated expiration: 2007-02-17
Also published as: IT8667138A0; IT1203537B; EP0234652A1; DE3763858D1

Description

This invention relates to an automatic transfer installation for the equipment used to wash the refuse bodies according to the preamble of claim 1.
Generally, the collection of the refuses is carried out by means of refuse bodies which are periodically emptied by special vehicles which carry out automatically the transfer of the refuses from the refuse body to the loading space of the vehicle.
In addition to the problem of the collection exists also an hygienic problem, inasmuch as the refuse bodies, in consideration of their function, have to be washed disinfected periodically; also this function is carried out automatically by special vehicle which withdraw the empty body, wash the interior and the exterior thereof by means of high pressure jets of water or a disinfectant solution and, once the washing has been terminated, depose again the refuse body on its place.
DE-A 2 536 774 shows one of said vehicles, called refuse body washers; these vehicles are generally formed, in the portion inherent to their function, by a caisson, mounted on the chassis of the vehicle, which is divided into sections containing both the washing liquid and the liquid pumping systems and, in the rear portion, by a washing water collecting chamber and by a refuse body lifting and overtuning mechanism disposed within said washing chamber.
A disadvantage of the above and the other known refuse body washers consists in that the transfer of the water from the washing chamber to the reservoir is carried out by means of centrifugal impeller pumps, of the self-priming or other type, which have the disadvantage of easily becoming clogged because of the continuous passage of water with the solid bodies suspended therein.
In addition, for a good operation of the pump it is necessary to have a certain quantity of water in the washing chamber, so as to avoid problems of cavitation at the suction mouth of the pump.
The presence of this water gives than rise to problems at the moment of the braking of the refuse body washing vehicles because of the subsequent lapping within the washing chamber.
US-A-4 525 277 discloses a method and an installation for cleaning a septic tank comprising a vacuum pump together with valves provided on a motor vehicle to create a vacuum within a compartment for sucking sludges or water into a compartment.
The installation of this document, however, does not provide a washing chamber for the washing of refuse collecting bodies in which the most important problem is to provide automatic means for controlling, actuating and driving the vacuum pump and the valves independently from the washing of the refuse bodies.
The object of the device according to the invention is to provide a mechanism of easy maintenance and non-critical use by means of which it will be possible to avoid the disadvantages of delicacy and assiduous maintenance due to the transfer methods described with reference to document DE-A 2 536 774, and which, in addition, will attain the object of completely discharging the water which collects on the bottom of the washing chamber.
To attain this and further objects which will be more clearly apparent from the following description, the invention proposes to provide an automatic water transfer installation according to claim 1.
The device according to the invention is described hereunder in a preferred, but not limiting, embodiment thereof, with reference to the annexed drawing which is a partially sectional sideview of the refuse body washing vehicle according to the invention.
Fixed to the chassis 1 of a motor vehicle are a high pressure pump 2 for washing the refuse bodies 21, and a vacuum pump 3; the reservoir 4, mounted on the chassis 1, is divided into three compartments: two side compartments 5 and 7 for clean water and a central compartment 6 for the recovery of the water used for the washing.
Situated within the central compartment is the mouth 8 of a sucking conduit 9 which extends to the vacuum pump 3; situated above said compartment 6 is a maximum safety valve 10 for the vacuum.
Above the compartment 7 for the clean water there is situated a pneumatically controlled floot- gate in the form of a spherical cock 11 which regulates the inflow of the washing water, coming from the washing chamber 13, through the conduit 12, into the compartment 6.
An end 14 of the conduit 12 debouches into the compartment 6, and the other end 15 grazes the bottom of the washing chamber 13; the washing water is filtered in respect of the more coarse deposits by the filtering grid 24 disposed within the chamber 13.
The washing chamber has a lower port 16 and an upper port 17, hinged in its rear portion.
Disposed adjacent the hinge of port 17 is a switch 18 connected to the floodgate 11.
Situated on the compartment 7 is a control station 19 into which there is inserted a double calibration (minimum and maximum) vacuostat 20, also connected to the floodgate 11; the vacuostat is apt to measure and regulate the vacuum within preselected limits.
The operation of the device according to the invention described hereinabove is as follows.
At the beginning of the service, within the central compartment 6 there is the atmospheric pressure; the vacuostat puts into action a hydraulic motor which actuates the vacuum pum 3. thus initiates to the creation of the vacuum in the interior of the central compartment 6 of the reservoir 4.
Said compartment 6 is connected to the washing chamber 14 through the stainless steel pipe 12 intercepted by the spherical floodgate 11 which, during the development of the vacuum, obviously remains closed.
Once a suitable vacuum value, of about 40%, has been attained, which value is more than sufficient for the application required and which does not give to structural problems, to the polycentrical reservoir of the refuse body washer, the vacuostat 20, suitably calibrated for said value, stops the vacuum pump and closed the contact which consents the opening of the spherical floodgate 11; however, this consent is intercepted by the switch 18 which maintains open the circuit as long as the shutter remains closed.
This requirement is justified by the fact that otherwise, after all the water present at that time within the washing chamber 13 has been sucked, a vacuum would be created within this latter which would give rise to serious structural problems.
After the termination of the washing of the refuse body 21, the switch 18 is closed by simply opening the upper port 17; at this point, the electric consent signal may prosecute and, by means of the pneumatic electric valve, the spherical cock 11 is opened, thus starting the transfer of the washing water which is sucked into the compartment 6.
The pressure within the compartment 6 begins to increase till, after the minimum calibration of the vacuostat 20 has been attained, the vacuum has been re-established and the cycle begins again.
This system, in addition to the advantages described hereinabove, has the advantages of being completely automatic, since it is independent from the stages of washing of the refuse bodies, and above all absolutely safe since it depends only on the calibrations set on the vacuostat.
Furthermore, there being no possibility of clogging, the installation does not require any particular maintenance.
In addition, said installation may be applied and realized on a conventional refuse body washer equipment, without requiring modifications of the original equipment and, therefore, without requiring additional cost.

Claims

1. An automatic water transfer installation for the washing of refuse collecting bodies, mounted on a motor vehicle (1) having, in its front portion, a reservoir (4) and, in its rear portion, a washing chamber (13) for washing the refuse bodies (21), said reservoir (4) being divided into compartments (5, 6, 7) for recovering the washing water and collecting the clean water intended to be used for the washing, characterized in that the installation provides: a vacuum pump (3), to create a vacuum in the interior of the washing water recovery compartment (6), and a vacuostat (20) operatively connected via a motor to said vacuum pump (3), and to a floodgate (11) inserted along a connection pipe (12) between the water recovery compartment (6) and the washing chamber (13); the vacuostat (20) actuating the vacuum pum (3), by means of said motor, and closing the floodgate (11) when the atmospheric pressure is attained in the recovery compartment (6) and, subsequently, closing the vacuum pump (3) and opening the floodgate (11) when the pre-established vacuum is attained in the recovery compartment (6).

2. An installation as claimed in claim 1, characterized in that the command sent by the vacuostat (20) to the floodgate (11) is intercepted by a switch (18) which habilitates the opening of the floodgate (11) only when a shutter (17) of the washing chamber (13) is open.

3. An installation as claimed in claim 1, characterized in that the vacuostat (20) is of the type with a double calibration (maximum and minimum).

4. An installation as claimed in claim 1, characterized in that the water recovery compartment (6) is provided with safety means (10) which are apt to take part in exceeding the pre-established maximum of the vacuum within the compartment (6) in case of a failure of the vacuostat (20).

5. An installation as claimed in claim 1, characterized in that the end (15) of pipe (12) inserted into the washing chamber (13) draws on the bottom of this latter.