Patent Document

DESCRIPTION 
     The present invention relates to a hydraulic supply device for a closed-circuit installation. 
     The present invention also relates to such an installation. 
     The installations targeted by the invention are in particular heating and/or cooling installations in which a heat transfer fluid flows along a closed circuit in order to pass successively through a heat or coldness production equipment, a utilising device, a pump, a buffer tank, a filter, etc. 
     It can be a heating installation, a cooling installation, or else an installation which can operate either as a heating or as a cooling installation, the thermal source then consisting of e.g. a reversible refrigerating machine, that is to say one capable of operating either as a heating means or as a cooling means. 
     The object of the present invention is to rationalise installations of the said type with regard to their components other than their utilising devices. 
     According to the invention, the hydraulic supply device for an installation using a heat transfer fluid in a closed circuit, this device comprising the following components for the heat transfer fluid: 
     a tank having a return orifice and a feed orifice, 
     a filter, 
     a pump, 
     an expansion vessel, is characterised by furthermore comprising an enclosure which houses at least part of said components while bringing them together in order to form a hydraulic unit. 
     Preferably, the enclosure is substantially fluid-tight. In this way substantial entries of water vapour into the enclosure and consequently the problems of condensation on the outside face of the wall of the tank are prevented. 
     It is also preferred that the enclosure should carry on its inside face a heat insulating lining. Such an internal lining is much easier to produce than external lagging on components having complex shapes such as tanks, pumps and their interconnecting pipes. The enclosure being thus internally insulated makes it possible to dispense with heat insulation on the components housed in the enclosure. 
     In particular, if the enclosure is substantially fluid-tight, the heat insulating lining can be made from a material which is not intrinsically fluid-tight, such as rock wool. Such a material is inexpensive and easy to apply. Thanks to the fluid-tightness of the enclosure there is no risk of it being saturated with water. 
     Preferably, between the inside face of the heat insulating lining and the outside face of the components housed in the enclosure, there is a space filled with air which constitutes additional insulation. 
     The arrangement of components inside the enclosure is such that possible condensates can flow without wetting the insulating lining. 
     According to an important feature of the invention, the filter is fitted inside the tank like a permeable partition subdividing the inside of the tank into a return chamber connected to the return orifice and a feed chamber connected to the feed orifice. This arrangement has multiple advantages. It eliminates the necessity of providing a location and a fitting for the filter in the circuit outside of the tank. Furthermore, in the tank, the filter has a large diameter and thus offers a negligible head loss. Similarly, for a closed circuit installation, where clogging prominently occurs just after the first operation, a filter of such size proves capable of stopping the initial impurities and then of continuing to allow normal operation without having to be cleaned. 
     If the return chamber is in the low position under the feed chamber, the impurities in any case have a tendency to fall to the bottom of the return chamber instead of remaining suspended on the bottom surface of the filter. 
     One of the important optional features of the present invention consists in fitting certain of the components such that they traverse the wall of the enclosure. In particular the pump or pumps are preferably fitted in such a way that the motor is outside of the enclosure. In this way the motor is ventilated better and the heat dissipated by the motor is prevented from heating up the inside of the enclosure, which is undesirable when the function of the installation is to cool the utilising devices. 
     It is also possible to fit the expansion vessel such that it traverses the wall of the enclosure in such a way that its adjustment device is accessible from outside of the enclosure. 
     It is also possible chat a flow-regulating valve installed downstream of the pump be so mounted that said valve extends through the wall of the enclosure. 
     It is advantageous that all of the components thus fitted such that they traverse the wall of the enclosure are grouped on one and the same side of the enclosure forming the back of a compartment adjacent to the enclosure itself. 
     Such a compartment can assume the form of a cabinet in which the electrical box is also installed. 
     If the return and feed orifices of the tank are oriented at about 90° with respect to each other, the feed path, making a 90° turn because of the usual geometry of pumps such as centrifugal ones, can exit on the same side of the enclosure as that through which the return path passes. This favours a rational connection with the rest of the installation. 
     According to a second subject of the invention, the heating and/or cooling installation comprising, along a closed circuit of heat transfer fluid: 
     a hydraulic supply device, 
     at least one thermal source, 
     at least one utilising device, 
     is characterised in that the supply device conforms with the first aspect. 
    
    
     Other features and advantages of the invention will furthermore emerge from the following description, given with reference to non-limitative examples. 
     In the appended drawings: 
     FIGS. 1 and 2 are two diagrams relating to two variants of an installation according to the invention; 
     FIG. 3 is a side view of the supply device according to the invention, with a vertical cross-section of the enclosure and tear-aways of the tank; 
     FIG. 4 is a top view of the supply device of FIG. 3, with a horizontal cross-section of the enclosure; 
     FIG. 5 is a view of a detail of FIG. 3, in a larger scale; 
     FIG. 6 is a view similar to FIG. 2, but relating to another embodiment; 
     FIG. 7 is a view similar to FIG. 3, but relating to a possible embodiment of the supply device of FIG. 6; and 
     FIGS. 8 and 9 are two plan-view diagrams relating to two other embodiments of the hydraulic supply device. 
    
    
     In the example shown in FIG. 1, the thermal conditioning installation comprises a device for supplying heat transfer fluid  1 , an equipment  2  forming a thermal source, and utilising devices  3 . These elements  1 ,  2 ,  3  are interconnected by a pipe  4  going from the source  2  to a return pipe  6  of the supply device  1 , a pipe  7  connecting a feed path  8  of the supply device  1  with the utilising devices  3 , and a pipe  9  extending from the utilising devices  3  to the inlet  11  into the thermal source  2 . 
     The installation therefore forms a closed circuit for the heat transfer fluid going from the supply device  1  to the utilising devices  3  and then to the thermal source  2  from where the fluid returns to the supply device  1 . The utilising devices  3  are connected in parallel between the pipes  7  and  9  which serve them. 
     In the example shown, each utilising device  3  is illustrated in the form of an exchanger  12  with the ambient air  13 . Each utilising device  3  tends to vary the temperature of the heat transfer fluid in the sense opposite to that of the temperature variation produced by the thermal source  2 . 
     The thermal source  2  is illustrated in the form of a refrigeration machine in which one of the thermally active constituents  16  is in a heat-exchange relationship with the heat transfer fluid closed circuit. 
     The example shown in FIG. 2 will be described only where it differs in comparison with that of FIG.  1 . 
     In this example, the feed path  8  of the supply device  1  is connected by a pipe  17  to the inlet  11  of the thermal source  2  and the return path  6  of the supply device  1  is connected by a pipe  14  to the outlets of the utilising devices  3 . A pipe  19  connects the outlet  18  of the thermal source  2  with the inlets of the utilising devices  3 . 
     The supply device  1  will now be described in more detail referring principally to FIGS. 3 and 4. 
     The supply device  1  comprises a tank  21  of generally cylindrical shape disposed along a vertical axis in the example shown. The tank  21  comprises a return orifice  22  which connects with the return path  6  and a feed orifice  23  which connects with the feed path  8 . The tank  21  forms part of the closed circuit for the heat transfer fluid. The return path  6  and the feed path  8  are connected with each other only by the tank  21  which, in service, is filled with heat transfer liquid. At its top the tank  21  has an automatic bleed device  24  for the automatic elimination of possible gas pockets. The tank  21  has the function of a thermal accumulator preventing sudden variations of temperature in the heat transfer fluid when the thermal source is started or stopped manually or automatically and when the consumption of the utilising devices  3  varies suddenly. 
     The supply device  1  furthermore comprises an expansion vessel  31  comprising a liquid chamber connected with the inside of the tank  21  by a pipe  32 . In a conventional manner, the vessel  21  encloses a moving partition (not shown) separating the liquid chamber from a gas chamber whose pressure can be regulated through an access  33 . In this way the pressure of the liquid in the tank  21  is at the same time regulated in a way which is independent of the variations in the volume of the liquid contained in the closed circuit of the installation. 
     The feed path  8  comprises pumping means produced in the shown example in the form of two centrifugal pumps  41  connected in parallel. The use of two pumps  41  is intended to avoid the risk of failure of the whole installation in the event of one of the pumps failing. Each pump  41  has an axial intake  42  connected to a respective feed orifice  23  of the tank  21 . Each pump  41  also has a radial delivery orifice  43  connected to a common delivery pipe  44 . In a way which is not shown, between each delivery orifice  43  and the delivery pipe  44  there is a non-return valve preventing one pump  41  in operation from delivering into another pump  41  which is stopped. 
     The delivery pipe  44  is equipped with a valve  51  for regulating the flow of the heat transfer liquid delivered by the pumps  41 . 
     The tank  21  is installed in an enclosure  61  of generally parallelepipedic shape supported by a base  62  upon which stands a support  26  of the tank. The enclosure  61  comprises an outer shell  63 , for example made of sheet steel. Against the inside face of the shell  63  is fixed a heat insulating lining  64  which covers it completely along the four lateral walls, under the top panel as well as over the frame  62 . Additional lining  66  is provided inside the support  26 . An air gap  67  is formed between the inside face of the lining  64  and the whole outside face of the tank  21 . One of the side walls of the enclosure  61  comprises an opening  67  for an inspection hatch  68  which is also made thermally insulating. 
     The enclosure is made substantially fluid-tight in order to prevent as far as possible the entry of atmospheric water vapour and consequently the formation of a large quantity of condensation on the surface of the tank  21  and of the other cold parts located inside the enclosure. It is not possible however to avoid small entries of vapour and consequently the formation of a small quantity of condensation which runs towards the bottom of the enclosure. For this reason, there is provided in the bottom of the enclosure, above the lining  64  of the bottom, a collecting receptacle  68  equipped with an evacuation orifice  69 . 
     A filter  81  is installed inside the tank  21  like a partition which is permeable to the heat transfer liquid, subdividing the interior of the tank  21  into a return chamber  27  connecting with the return orifice  22  and an feed chamber  28  connecting with the feed orifices  23 . The filter  81  is for example made in the form of a grid of substantially circular shape, flat or preferably dish-shaped in order to resist the pressure difference between the chambers  27  and  28  by a vault effect. The filter  81  is welded all around its periphery to the inside face of the peripheral wall of the tank  21 . The filter  81  is disposed in a horizontal plane. 
     The wall of the tank  21  is also traversed by two openings  29 , one of them located just below and the other one just above the filter  81 . As shown in FIG. 4, these openings  29  allow the fitting of heating elements  82  each one in the form of a rod which protrudes radially inside the tank  21  and are secured against the outer face of the wall of the tank  21  by a flange  83  which is extended outwardly by an electrical connection device  84 . Such elements are intended to serve as a complementary source of heating in addition to the thermal source  2  if the latter is insufficient when it is operating as a heat source, or else is substituted for the thermal source  2  when the latter for example consists of a refrigeration machine which is not reversible as a heat pump, so that, despite this, the installation can operate as a heating installation for example during the winter period. The orifices  29  are oriented towards the inspection hatch  68 . 
     Furthermore, an electrical heating mat  86  is secured against the outer face of the wall of the tank  21  in the vicinity of the feed orifices  23  because as this zone comprises many walls separating the heat transfer fluid from the gaseous space  67  inside the enclosure  63 , it is more exposed to the risk of freezing. 
     The pumps  41 , the expansion vessel  31 , and the valve  51  are installed in a fluid-tight manner in appropriate openings of the enclosure  61 , while extending through a same wall  71  of that enclosure. Said wall  71  simultaneously forms the back of a compartment  87  configured as a technical cabinet also housing the electrical box  88 . 
     The power supply cable  89  (FIG. 4) of the heating mat  86  extends through the wall  71  of the enclosure in a fluid-tight manner and is connected to the electrical box  88 . In a way which is not shown, the power supply cable of each element  82  can connect the connecting device  84  with the electrical box  88  via a cable which is for example grouped with the cable  89  for traversing the wall  71 . 
     The assembly is such that the pump body  46  of each of the pumps  41  is inside the enclosure  61  whilst the motors  47  of the pumps  41  protrude into the compartment  87 . The delivery path of the pumps  41  from the delivery orifices  43  and passing through the body  52  of the valve  51  extends in a plane parallel with the wall  71  traversed by the components  31 ,  41  and  51 , close against the inside lining of this wall  71 . The actuating device  53  of the valve  51  protrudes into the compartment  87  so that it is accessible and allows adjustment of the valve  51  from this compartment. 
     The expansion vessel  31  is installed in such a way that the cover  33  providing access to the adjustment means is in the compartment  87  to allow adjustment of the pressure of the tank  21  from the compartment  87 . 
     The return pipe  6  and the delivery pipe  44  leave the enclosure through two orifices  72  formed through the same lateral wall  73  of the enclosure  61 . The wall  73  is adjacent to the wall  71  through which the components  31 ,  41 ,  51  are mounted, and opposite the wall  74  equipped with the hatch  68 . The return pipe  6  is a short pipe oriented radially with respect to the tank  21  and ending directly at the return orifice  22  located immediately behind the wall  73 . The feed path  8  forms, as seen from above (FIG.  4 ), a 90° bend inside the pump body  46 . The feed orifices  23  are oriented towards the wall  71 , substantially at 90° to the return orifice  22  about the vertical axis of the tank  21 , so that after the 90° turn in the pumps the feed path  8  ends at the same wall  73  as the return path  6 , as has been described. The axis of the pumps  41  is horizontal and radial with respect to the tank  21 . The inlet pipes  42  of the pumps  41  are very short straight pipes directed radially with respect to the axis of the tank  21 . The delivery pipe  44  is also straight. If a single pump  41  were provided, all the pipes provided for the heat transfer fluid in the supply device  1  could be strictly straight. In the example shown, this very advantageous condition could not be achieved entirely due to the necessary connection between the deliveries of the two pumps  41 . 
     As shown in detail in FIG. 5, the wall  71  can, for the mounting of the components  31 ,  41 ,  51 , have a large window  76  obturated by a heat insulating shield  77  through which the components  31 ,  41 , and the valve  51  (not shown in FIG. 5) are mounted. 
     The operation and use of the supply device  1  will now be described. 
     When at least one of the pumps  41  is operating, the heat transfer liquid is taken in through the return orifice  22 , enters into the tank  21  in the return chamber  27 , passes through the filter  81  into the feed chamber  28  which it leaves through at least one of the feed orifices  23 . 
     The impurities stopped by the filter  81  tend to drop spontaneously to the bottom of the tank  21  where they are in no way harmful. The temperature inside the enclosure  61  is close to that of the heat transfer liquid, which is generally regulated where it passes in contact with the thermal source  2  (FIGS.  1  and  2 ). The heat dissipated by the motors  47  remains outside. 
     If this temperature becomes close to 0, the heating mat  86  can be put into operation automatically in order to prevent freezing at the intakes of the pumps. 
     Such a supply device can operate for years without necessitating any maintenance inside the enclosure  61 . If it is desired to clean the inside of the tank  21 , the latter is drained through a bottom tap which is not shown, the two elements  82  are removed and a suction nozzle is introduced through the corresponding openings  29  in order to unclog the return chamber  27  and the feed chamber  28  respectively, including both sides of the filter  81 . This operation is facilitated by the fact that the openings  29  are opposite the hatch  68 . 
     The supply device is particularly economic to manufacture, very practical in use and minimises maintenance and head losses undergone by the heat transfer fluid. 
     The example shown in FIG. 6 will be described only where it differs with respect to the one in FIG.  1 . 
     In this example, a section  101  of the thermal source  2  is an integral part of the hydraulic supply device  1  and is integrated inside the enclosure  61  and in particular inside the volume surrounded by the heat insulating lining  64 . 
     More particularly, the section  101  of the thermal source  2  which is inside the enclosure  61  comprises the refrigeration compressor  103 , a refrigeration fluid tank  106 , a refrigeration fluid pressure relief device  107  and a device  116  serving as an evaporator for the refrigeration fluid and as a cooling exchanger for the heat transfer liquid. The pipe  17  is now entirely inside the enclosure  61  between the delivery of the pump  41  and the inlet into the evaporator-exchanger  116 . The outlet  118  of the evaporator-exchanger  116  consists of a pipe which emerges outside of the enclosure  61  through the same face of the enclosure  61  as that on which the connector  6  for return to the inside of the tank  21  is located. 
     As regards the refrigeration circuit, the delivery  108  of the compressor  103  consists of a pipe which traverses the wall of the enclosure  61  and then is connected to the inlet of the condenser  104  which constitutes the essential element of the section  102  of the thermal source  2  which is located outside of the enclosure  61 . An outlet pipe  109  of the condenser  104  also passes through the enclosure  61  and is then connected to the refrigeration fluid tank  106 . The region  106 f of the tank  106  which is located below the liquid level in this tank is connected through the pressure relief device  107  with the inlet of the evaporator section of the evaporator-exchanger  116 . The outlet of this evaporator section is connected by a pipe  111  with the inlet of the compressor  103 . 
     The advantage of this embodiment is that the parts of the refrigeration machine and more generally of the thermal source which also need to be heat insulated are also grouped inside the insulated enclosure  61 . In this way the problems of heat insulation in the installation are greatly simplified, a major portion of the technical components of the installation are grouped inside a same enclosure and external insulation is dispensed as regards elements such as the compressor or the evaporator, which makes these elements more accessible for maintenance. 
     Thermodynamically speaking, the compressor operates for compressing the refrigeration fluid up to a temperature which can be rather high. Practically however, the compressor nevertheless constitutes a cold section of the installation because it is usually maintained at low temperature by a cooling system using the vapour coming from the evaporator of the refrigeration circuit just before its inlet into the compression chamber of the compressor. 
     In a way which is not shown, inside the enclosure  61  there are also the regulating devices, if any, of the refrigeration machine, such as the regulation of the throttle carried out by the pressure relief device  107  for the refrigeration fluid flowing therethrough. 
     Independently from the above, the embodiment of FIG. 6 also distinguishes from that of FIG. 3 in that there is mounted inside the enclosure  61 , a different filter  181  of cylindrical shape having an annular edge  182  surrounding the return orifice  6  and, at the opposite end, an annular edge  183  surrounding an inspection orifice  184  formed in the wall of the tank  21 , and normally obturated by a closing plate. When the pump  41  is operating, it produces a depression inside the tank  21 . The cylindrical shape of the filter  181  has an excellent resistance to the bursting stress which results from this depression, particularly when the filter is clogged. At the same time, the production of a cylindrical filter is inexpensive. The inspection hole  184  conveniently allows insertion of a heating element, or of a suction nozzle for cleaning purposes, or else allows replacement of the filter  181 . 
     In the embodiment shown in FIG. 7, the condenser  104 , instead of being physically separated from the enclosure  61 , is secured to the latter, on the outside of the heat insulation lining  64 . 
     Furthermore there can be seen on this figure, better than in FIG. 6, the particular embodiment of the refrigeration tank  106  in the form of an elongated bottle with a substantially vertical upper region  106   g,  intended to contain the gaseous phase and a lower region  106   f  intended to contain the liquid phase and which forms an obtuse angle of about 100°, thereby to be virtually horizontal. The region  106   f  is integral with supports  121  which extend upwards in order to also support the evaporator-exchanger  116  and the compressor  103 . Another support  122  of the compressor  103  stands solely on the tank  106 . FIG. 6 shows that the gaseous region  106   g  is connected to the delivery  108  of the compressor  103  by a connecting pipe  123 . 
     In the example shown in FIG. 8, the thermal source  2  is no longer a refrigeration machine but a system of heat exchange with the water  131  of a swimming pool  132  having a water treatment device  133 . Such a treatment device takes water from the swimming pool  132  and subjects it to cleaning and filtration treatments etc. The water is then returned to the swimming pool  132 . In this version of the invention, the water flowing through the treatment device  133  is diverted into the enclosure  61  through an inlet pipe  134  and then returns to the treatment device  133  through a return pipe  136 . In the enclosure  61 , the water from the swimming pool flows through a heat exchanger  141  whose other path is traversed by the delivery  17  of the pump  41  upstream of the orifice  118  for feeding the heat transfer fluid out of the enclosure  61 . 
     Starting from the orifice  118 , the heat transfer fluid can go directly to the utilising devices or can pass through a refrigeration machine intended to further lower its temperature. 
     In the example shown in FIG. 9, the heat transfer fluid has two separate circuits. A first circuit simply provides for the circulation of the heat transfer fluid from the tank  21  through the pump  41  to the utilising devices and the return through the inlet orifice  6  into the tank  21 . The other circuit comprises a second pump  148  with an intake  149  in the tank  21 , and a delivery  151  into the thermal source  2  which can, as shown, be at least partly located inside the enclosure  61 . From the source  2 , the heat transfer fluid returns directly to the tank  21  through a pipe  152 . 
     This invention is not of course limited to the examples shown and described. 
     In particular, the device can, with minor modifications, be installed in such a way that the axis of the tank  21  is horizontal. The filter  81  is then, without disadvantage, disposed in a vertical plane.

Technology Category: 2