The invention relates to the control, or management, of a condensate removal pump. More specifically, the invention relates to the detection of condensate levels, in a container, and the control of a pumping system according to these levels.
Such condensate removal pumps are implemented in particular in air conditioning systems, refrigeration systems, ventilation systems or heating systems.
A number of techniques for producing a device for detecting condensate levels and controlling the pump are already known. It is particularly known to provide a float, floating in a container, and cooperating with detection and/or actuation means, according to the condensate level in the container.
The invention relates, according to one aspect, to a liquid level detection device of this type, comprising a float intended to be placed in a container, capable of moving according to the level of liquid in the container, and an actuation element driven by said float.
A removal pump can, in particular, be used in an air conditioning system in which it is desirable to regularly remove, by pumping, the liquid (or condensate) resulting from condensation of the water vapor present in the ambient air that is cooled and which is collected in a container. This enables overflow of said container to be avoided and the amount of stagnant water in said container to be limited.
Thus, in an air conditioning system including a detection device of the type mentioned above, when the height of the liquid rises to the maximum level allowed, the float rises and drives the actuation element. According to one approach, this actuation element can act on a monostable microswitch, having a pushbutton. For example, when the level reached is a maximum level (Ma) at which point the pump should be turned on, the actuation element can be arranged so as to press or release said pushbutton of the microswitch. The microswitch then changes states and controls the turning on of a pump that pumps the liquid into the container. The pump then generally moves this liquid to a wastewater line.
The problem of this solution is that, once the liquid level is at a level slightly lower than the maximum level Ma, the pushbutton returns to its previous state and stops the pump. The container empties therefore very few, and the pump is very often activated and stopped, in the vicinity of the maximum level Ma (i.e. between the maximum level and a substantially lower level).
This solution is of course not optimal, for reasons of safety, efficacy and durability. For this reason, known removal pump control systems distinguish, in addition to the maximum level Ma, a minimum level Mi. The pump is stopped only when this minimum level is reached, thereby enabling substantially regular cycles to be defined (allowing the definition of a delta of pumping, i.e. the difference between the maximum level and the minimum level, that is optimized).
This cannot therefore be achieved efficiently with a monostable microswitch (i.e. capable of adopting a stable position, by default, for example stopping the pump, and an unstable position, when a force is applied on the pushbutton, for example actuating the pump), unless accepting a very low delta of pumping. It is of course possible to use a bistable microswitch. However, they are more expensive, and it would then be necessary to provide a specific actuation in order to control the stopping of the pump, when the minimum level is reached.
In condensate removal pumps, numerous constraints must be taken into account. They must be inexpensive, easy to assemble and, depending on the case, easy to adjust, have a low profile and require little or no intervention or maintenance.
Moreover, in this type of system, it is possible for example for the pump to be clogged or unserviceable, for a line to be clogged or pinched, for the first microswitch to be unserviceable, or for the inflow of liquid into the container to be abnormally high. In this type of situation, the liquid is no longer pumped, or not pumped quickly enough, and the height of the liquid inside the container rises beyond the maximum level allowed. The liquid then risks overflowing from the container.
Specific detection of a safety or danger level, above the maximum level, is therefore generally provided.
The invention is intended in particular to propose a device for controlling a condensate removal pump that is safe, simple, reliable and/or inexpensive.
In particular, the invention is intended to propose such a control device capable of detecting at least three distinct levels (minimum level, maximum level and safety level).
The invention relates, according to one of its aspects, to a device for controlling a condensate removal pump, comprising:
According to the invention, said actuation element is configured and mounted so as to act selectively on a first and a second microswitch respectively having a first and a second pushbutton mobile between two positions, so as to define three distinct states:
Said actuation element can in particular be configured and mounted so that said device switches:
Thus, with only two microswitches, the invention enables the pump to be controlled so that it remains on between the maximum level (the starting of the pump having been engaged when said level was reached) and the minimum level. Conversely, the pump, stopped when the minimum level has been reached, remains stopped until the maximum level is again reached. The detection of the alarm level is also ensured.
Said microswitches can in particular be monostable microswitches, wherein said first position is a stable position and said second position is an unstable position.
Said actuation element can have stabilization means cooperating with at least said first pushbutton in order to hold it in its unstable position while said condensate level falls, and is above said predefined minimum level (Mi).
Thus, the pushbutton remains pressed, while the level falls. There is therefore a decorrelation between the movement of the float and the actuation element, while the condensate level falls. In other words, the correlation between the movement of the float and that of the actuation element is not permanent, but instead selective.
The stabilization means can, for example, comprise a friction surface, ensuring that the actuation element remains in a substantially fixed transient position, while the condensate level falls.
The stabilization means can, alternatively or in combination, comprise at least one magnet.
Said first and second microswitches can be mounted so that said actuation element is held, when the device is in the active state, by said pushbuttons.
The safety action can be chosen among at least one of the followings: stopping of the machine producing condensate, generation of an alarm, for example a sound or visual alarm, and activation of a second pump. This list is non-limiting.
According to a specific embodiment, the actuation element can pivot around a pivot and includes a first arm portion located on a same side of said pivot.
The first and second microswitches can define, between their pushbuttons, a gap, and the first actuation element portion may be housed in this gap.
The first and second pushbuttons can be arranged opposite one another.
The first and second microswitches can be identical or quasi-identical.
The device for controlling a condensate removal pump can include two stop elements apart at a distance from one another and separated by an empty space in which a second portion of the actuation element is located, and these stop elements are driven by the movement of the float and in turn drive the actuation element.
The invention also relates, according to another aspect, to an air conditioning or heating system including a liquid collection container, equipped with a device for controlling a condensate removal pump as defined above.
Other features and advantages of the invention will appear in the following detailed description of specific embodiments of the invention provided by way of non-limiting examples. This description refers to the appended drawings in which:
This device can in particular be implemented in the liquid pumping system of
in which:
Thus, when the height of the liquid rises beyond the maximum level allowed, the float rises and drives the pivoting arm, which presses or releases the second pushbutton. Once the safety level has been reached, the second microswitch changes states and controls the activation of the safety system.
When used in an air conditioning system, the safety system can, for example, warn a person of the risk of overflow of the container and/or cut off the arrival of cold water in the heat exchanger of the air conditioning system and/or cut off the electrical power supply of the air conditioning system. The risk of overflow of the liquid is thus considerably reduced.
In addition, the same pivoting arm is used to press on the first and second pushbuttons and cause the states of the first and second microswitches to be changed. This has the advantage of limiting the number of parts of the device and therefore of limiting the cost and bulk of same.
According to an embodiment, the device is such that:
This particular arrangement has the advantage of further limiting the bulk of the device.
According to an embodiment, the pushbuttons of the microswitches are arranged opposite one another.
This particular arrangement has the advantage of further limiting the bulk of the device, as well as of balancing the forces exerted on each side of the pivoting arm, thus reducing the force exerted on the float by the pivoting arm.
According to an embodiment, the first and second microswitches are identical or quasi-identical (they can, for example, be different colors), thereby enabling one to manage only a single set of microswitches in the production of the device, enabling this production to be simplified by limiting the risks of assembly error (by preventing problems of inversion of the first and second microswitches) and enabling the cost of the device to be limited in principle.
According to an embodiment, the pumping system is such that:
According to an embodiment of the invention, the detection device includes two stop elements at a distance from one another and separated by an empty space in which a second portion of the pivoting arm is located, in which these stop elements are driven by the movement of the float and in turn drive the pivoting arm.
The two stop elements at a distance from one another enable, when the pump is activated and the level of liquid in the container falls, the movement of the float (which follows the liquid level) to be prevented from immediately driving the pivoting arm and therefore the actuation of the first microswitch and the stopping of the pump. Conversely, these two stop elements enable, when the pump stops and the level of liquid in the container rises, the movement of the float to be prevented from immediately causing the activation of the pump. The mode of operation of these two stop elements is described in detail and illustrated below.
The two stop elements are fully effective if the pivoting arm is capable of remaining in a transient position when it is not driven by one of the stop elements. However, the pivoting arm is generally subjected to disruptive forces, in particular its own weight, which move the pivoting arm away from this transient position. It is noted that to limit the influence of the weight of the pivoting arm, this arm is advantageously made of a lightweight material.
To oppose these disruptive forces, according to an embodiment, the device includes stabilization means enabling the pivoting arm to be stabilized in a transient position.
Said stabilization means can have various shapes and various modes of action.
According to an embodiment, the stabilization means slow the movement of the pivoting arm by generating frictional forces. When the pivoting arm is in a transient position, these frictional forces opposite said disruptive forces. For example, the stabilization means include a material with a high friction coefficient arranged between the pivoting arm and the pivot of said arm, so as to generate frictional forces between the arm and its pivot.
According to another embodiment, the stabilization means generate anchoring forces that opposite said disruptive forces when the pivoting arm is in a transient position. For example, the stabilization means include a magnet arranged at the level of said transient position and the pivoting arm is magnetic or has a magnet.
It is noted that the frictional forces or the anchoring forces mentioned above must be capable of being overcome by the driving forces exerted by the stop elements on the pivoting arm.
The detection device and the pumping system of the invention can be used in various systems and, in particular, in an air conditioning system or in a heating system such as a condensing boiler.
The invention also relates to a heating or air conditioning system including a liquid or condensate collection container equipped with a system for pumping this liquid according to the invention.
Generally, in air conditioning or heating systems, the space allocated to the pumping system is restricted for reasons of overall bulk of the system and/or for aesthetic reasons. One will therefore understand the benefit of having a low-profile pumping system (in particular owing to its vertical movement) like that of the invention.
The system 10 includes:
The device 100 includes:
Below, the horizontal direction of reference is that of the level of liquid in the container 20, shown with a dotted line in
The float 102 is secured by a rod 104, guided vertically in translation by at least one guide element. In the example, this guide element is a guide sleeve 106 outside the rod 104. The guide element can also be a rail, or a slide. The rod 104 has two stop elements remote from one another according to the vertical direction: a bottom stop element 107 and a top stop element 108. These stop elements 107, 108 mutually define an empty space, or a gap 109.
The pivoting arm 130 pivots around a cylindrical pivot 132. It has a general āLā shape with a small branch 133 and a large branch 134 substantially perpendicular to one another. The small branch 133 is more vertically oriented and the large branch 134 is therefore more horizontally oriented. The pivot 132 passes through the central portion of the small branch 133. The pivoting arm 130 has a first arm portion 135 located on the same side as the pivot 132 above it. This first arm portion 135 belongs to the small branch 133. The pivoting arm 130 also has a second arm portion 136 located between the stop elements 107 and 108, in the gap 109. This second arm portion 136 corresponds to the end portion of the large branch 134.
The small branch 133 is made of a material with a high friction coefficient, for example rubber, so that frictional forces appear when the pivoting arm 130 moves with respect to the pivot 132, thereby slowing the movement of the pivoting arm 130 and enabling it to be stabilized in a transient position when it is not driven by one of the stop elements 107 or 108. The small branch 133 of the pivoting arm 130 therefore forms stabilization means in the sense of the invention, due to the fact that it is made of a material with a high friction coefficient.
The first and second microswitches 110, 120 are both mounted on a plate 101 made in one piece with said guide element (i.e. the guide sleeve 106). These microswitches 110, 120 are arranged so as to define a gap 111 between their pushbuttons 112, 122. The first arm portion 135 is housed in this gap. The pushbuttons 112, 122 of the first and second microswitches 110, 120 are arranged opposite one another, the first arm portion 135 being centered with respect to its microswitches when it is in a substantially vertical position. Concretely, in reference to
In the example, when the first arm portion 135 is vertically oriented, it is in contact with the two pushbuttons 112, 122. In other words, the distance between the two pushbuttons 112, 122, when they are both in their raised position, is shorter than the width of the first arm portion 135.
The first microswitch 110 is connected to the electric motor 13 and controls the activation of the motor 13, and therefore of the pump 12, when the first pushbutton 112 switches to the pressed position. In addition, it controls the stopping of the motor 13, and therefore of the pump 12, when the first pushbutton 112 switches to the raised position.
The second microswitch 120 controls the activation of the safety system 30 when the second pushbutton 122 switches to the raised position.
In reference to
When the liquid level N rises, the float 102 rises and the bottom stop element 107 pushes the second portion 136 of the pivoting arm 130 upward. As the force exerted by the stop element 107 is greater than the frictional forces between the pivoting arm 130 and its pivot 132, the arm 130 pivots. The first portion 135 of the pivoting arm 130 then moves to the left (in reference to
It is noted that, over time, the first portion 135 of the pivoting arm 130 releases the pressure exerted on the second pushbutton 122 which rises spontaneously to its raised position under the effect of return means working in compression, housed in the housing 123, but it does not release this pushbutton 122 enough for the second microswitch 120 to change states.
With the pump 12 activated, the liquid level N and the float 102 go back down. Insofar as the top stop element 108 does not come into contact with the arm portion 136, the pivoting arm 130 remains in the position that it occupied, this position being a transient position in the sense of the invention. This is possible owing to the frictional forces between the arm 130 and its pivot 132, which oppose, in particular, the weight of the arm 130. In addition, it is noted that the forces exerted by the pushbuttons 112 and 122 on the arm 130 oppose one another, at least partially, thereby enabling the disrupting effect of these forces to be limited.
When the top stop element 108 pushes the second portion 136 of the pivoting arm 130 downward, the force exerted by the stop element 108 is greater than the frictional forces and the arm 130 pivots. The first portion 135 of the pivoting arm 130 then moves to the right (in reference to
The liquid level N will then rise, with the pivoting arm 130 remaining in a transient position, insofar as it is not driven by the bottom stop element 107. A new filling/pumping cycle begins.
As indicated above, it is possible for a malfunction to occur (i.e. no pumping, or insufficient pumping with respect to the volume of liquid arriving in the container) causing the liquid level N to rise above the maximum level allowed Ma. In such a case, the float 102 and the bottom stop element 107 push the second arm portion 136 upward so that the arm 130 pivots. The first arm portion 135 thus moves to the left and increasingly releases the second pushbutton 122, which then spontaneously moves back up to its raised position. When the liquid level N reaches a safety level Ns, the first arm portion 135 sufficiently releases the pushbutton 122 so that the second microswitch 120 changes states and controls the activation of the alarm 30.
To pump the condensation liquid 6, the air conditioning system 1 is equipped with a pumping system 10 like that of
It is noted that the pumping system 10 can be placed directly in the collection vat 4, which, in this case, would be considered to be a container in the sense of the invention.
In this example, the safety system 30 is a system for cutting off the electric power supply of the air conditioning system, enabling the fan 3 in particular to be stopped. This safety system 30 is integrated in the air conditioning system 1. This safety system 30 can be associated with or replaced by other types of safety systems and, in particular, by a light or sound alert system and/or a system for cutting off the fluid supply of the exchanger 2.
It should be noted that in the figures, a pushbutton can be in the pressed state when it ranges from being slightly pressed to being fully pressed. In this pressed state of the pushbutton, the associated microswitch is in the unstable state. Simply in order to facilitate the reading and understanding of
In
When the float 102 rises to a level N=Ma, the condensate level having risen, the branch 134 of the actuation element 130 is constrained by the bottom stop element 107 and the actuation element 130 pivots around the pivot 132 so as to press the first pushbutton 112, while the second pushbutton 122 remains in the pressed state. The switching of the first pushbutton 112 from the raised state to the pressed state enables the activation of the pump to be controlled so that the condensate level decreases in the container. The device is then in an active state (the pump is on).
During this decrease in condensate volume, the actuation element remains in the actuation position of the first pushbutton 112, as shown in
When the level of the float 102 (or condensate) reaches a level N equal to around Mi, the top stop element 108 forces the actuation element 130 to pivot so as to return to a position shown in
During normal operation of the device and the pump, the second microswitch is not activated.
In the event of a malfunction of the device and/or the pump, the condensate level continues to rise in the container. When it reaches a level Ns, as shown in
As indicated above, the stabilization means can be formed by something other than a friction surface.
Also in this example, shown in
It is also noted that the microswitches 110 and 120 are placed perpendicularly to those of
Also in this horizontal direction, two microswitches 110 and 120 of another device shown in
A device similar to that of
According to other embodiments, not shown, the rod 104 can act directly on the pushbuttons, without the means of a lever. Depending on the case, the size of the float can then be increased, to provide sufficient force to act on the pushbuttons. The rod 4 can, for example, have a ring capable of sliding, remaining immobile while the level falls, until the minimum level is reached. A stop mounted on the rod can then drive the ring, thereby causing the pump to stop.
It is also possible for the rod to be suitable by itself for ensuring the actuation of the pump in the manner desired, for example with a relief suitable for defining cams, acting on pushbuttons according to the level (the distinct actuation between the direction of rising and falling of the level can be ensured by controlled rotation, via these cams, of the rod).
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