Thermostatic assembly, including thermostatic cartridge

Abstract

Thermostatic assembly, in particular thermostatic cartridge. This thermostatic assembly (1) comprises a casing (10) delimiting a mixing chamber (11), a hot fluid inlet (14), a cold fluid inlet (15), and a mixed fluid outlet (16). Within the chamber, a spool (20) for regulating the temperature of the mixed fluid is movable along an axis (XX) of the chamber so as to close, in inverse proportions, a hot fluid passage and a cold fluid passage. A thermostatic element (30) comprises a body (31), arranged within the chamber to be in contact with the mixed fluid and to be linked to the spool during movement, and a piston (32), connected to the casing and centered on the axis. The piston is received in the body in a movable manner under the action of a thermodilatable material (33) of the body, by being mounted axially sliding in a guide (34) of the body, from which the piston emerges outside the body.A sealing sleeve (37), coaxially mounted around the guide and piston to seal their sliding assembly, comprises a first part, fixedly attached to the guide along the axis, and a second part applied against the piston all around the axis in sliding contact along the axis. Figure for the abbreviation: Figure 1.

Description

Title of the invention: Thermostatic assembly, in particular thermostatic cartridge

[0001] The present invention relates to a thermostatic assembly, in particular a thermostatic cartridge.

[0002] To regulate the temperature of a mixture of a hot fluid and a cold fluid, particularly a mixture of hot and cold water in a sanitary installation, it is known to use a thermostatic element and a spool, which are arranged in a hollow outer casing, typically a cartridge body to be inserted into a valve body. The thermostatic element comprises a piston, which is normally fixed relative to the casing, and a body, which contains a thermodilatable material and relative to which the piston is displaceable in translation along an axis under the action of the thermodilatable material during its expansion. The body includes a guide, from which the piston emerges outside the body and in which the piston is mounted to slide along the axis.The spool is connected to the body so that it moves along its axis within a chamber in the casing. This allows it to close, in inverse proportions, two passages: a first passage, axially delimited between the spool and the casing and supplied with hot fluid from a hot fluid inlet delimited by the casing, and a second passage, axially delimited between the spool and the casing and supplied with cold fluid from a cold fluid inlet delimited by the casing. The hot and cold fluids that the spool allows to pass through these two passages to reach the chamber mix within the chamber and form, downstream of the spool, a mixed fluid. This mixed fluid then exits the casing, flowing along the body of the thermostatic element to act thermally on the thermodilatable material.By changing the position of the piston relative to the casing, usually by means of a dedicated control mechanism, the thermostatic control temperature can be set; that is, the equilibrium temperature around which the temperature of the mixed fluid is regulated. An example of this type of cartridge is provided by FR 2 921 709.

[0003] The sliding assembly of the piston in the guide of the thermostatic element body must be sealed to prevent hot, cold, and / or mixed fluids from entering the body and / or to prevent lubricants intended for the sliding assembly from escaping from the thermostatic element. To this end, the thermostatic element generally incorporates a sealing bellows, which surrounds the sliding assembly and whose opposite ends along the axis are respectively fixed to the body and the piston. In practice, this bellows The seal is satisfactory but occupies a substantial amount of space inside the aforementioned casing, partially filling the chamber. This can impede fluid flow within the chamber and limit its maximum flow rate, and may also necessitate reinforcing the bellows' connection to the piston to withstand the fluid flow within the chamber. The assembly between the thermostatic element body and the spool is also complicated, as it is generally necessary to temporarily detach the bellows to allow for this assembly, before repositioning the bellows once the spool is connected to the body.

[0004] The object of the present invention is to propose a new thermostatic assembly in which the sliding mounting of the piston in the guide of the body of the thermostatic element is sealed in an improved, in particular less restrictive way.

[0005] To this end, the invention relates to a thermostatic assembly, comprising:

[0006] - an envelope in which are delimited:

[0007] - a chamber, which defines an axis and in which a hot fluid and a cold fluid mix to form a mixed fluid,

[0008] - a hot fluid inlet through which the hot fluid enters the chamber from outside the envelope,

[0009] - a cold fluid inlet through which the cold fluid enters the chamber from outside the envelope, and

[0010] - a mixed fluid outlet through which the mixed fluid contained in the The room emerges from the envelope.

[0011] - a temperature control valve for the mixed fluid, the valve being movable along the axis inside the chamber so as to close, in inverse proportions, a hot fluid passage and a cold fluid passage, each axially delimited between the spool and the casing, the hot fluid passage being supplied by the hot fluid from the hot fluid inlet while the cold fluid passage is supplied by the cold fluid from the cold fluid inlet, and

[0012] - a thermostatic element comprising:

[0013] - a body, which contains a thermodilatable material and which is at least partially arranged in the chamber to be in contact with the mixed fluid and to be connected to the spool so as to cause the spool to move along the axis inside the chamber,

[0014] - a piston, which is connected to the casing by being centered on the axis and which is partially received in the body in a movable manner along the axis under the action of the thermodilatable material during an expansion of the thermodilatable material, the piston being mounted to slide along the axis in a guide of the body, from which the piston emerges outside the body, and

[0015] - a sealing sleeve, which is attached coaxially around the guide and the piston so as to seal the sliding assembly of the piston in the guide, which sealing sleeve includes a first part, which is fixedly attached to the guide along the axis, and a second part which is applied against the piston all around the axis in sliding contact along the axis.

[0016] One of the ideas underlying the invention is to replace the bellows seal mentioned above with a sealing sleeve, which is fixed coaxially around the guide along its axis and coaxially around the piston, not fixedly but in sliding contact with it along its axis. This sealing sleeve is thus applied in a scraping manner against the piston all around its axis, ensuring a tight seal between it and the piston, even during axial movements of the piston relative to the body. The sealing sleeve is advantageously flexible, exhibiting in particular elastic resilience which is used to ensure a substantially radial application of the sealing sleeve against the piston.In all cases, the sealing sleeve has the advantage of being able to be dimensioned along its axis in a particularly compact manner, especially compared to the sealing bellows mentioned above. Thanks to this axial compactness of the sealing sleeve, the fluid flow in the chamber is less, or even not at all, disturbed around the piston, which does not alter the performance of the thermostatic assembly according to the invention in terms of maximum permissible flow rate. The assembly between the body of the thermostatic element and the spool is advantageously facilitated by the sealing sleeve, in that the latter can be dimensioned sufficiently compactly so that, while remaining in place on the body and opposite the moving piston, it does not interfere with the spool during this assembly, as explained in more detail below.More generally, the sealing sleeve of the thermostatic assembly according to the invention makes it possible to improve the performance of this thermostatic assembly, in relation to, among other things, its assembly, its thermostatic regulation capabilities, its cost, etc., also as detailed below.

[0017] According to additional advantageous features of the thermostatic assembly according to the invention, taken individually or in all technically possible combinations:

[0018] - The drawer is provided with a passage, which crosses the drawer axially from one side to the other, in being centered on the axis, and which receives the guide in a complementary way, the maximum outside diameter of the sealing sleeve being less than the minimum inside diameter of the passage.

[0019] - The guide and the passage cooperate through complementary forms to link in de- placement along the axis of the body and the drawer.

[0020] - The second part of the sealing sleeve is axially juxtaposed to the guide.

[0021] - The second part of the sealing sleeve is axially juxtaposed to the guide.

[0022] - The maximum axial dimension of the sealing sleeve is less than maximum outside diameter of the guide region, by which the first part of the sealing sleeve is fixed along the axis to the guide.

[0023] - When the piston is fully retracted into the body, the piston emerges axially of the sealing sleeve over an axial extent that is less than or equal to one millimeter.

[0024] - The second part of the sealing sleeve is applied against the piston of in a manner substantially radial to the axis by the effect of elastic resilience of the sealing membrane.

[0025] - The piston is externally smooth on at least all of its part that emerges from the guide when the piston is fully extended relative to the body.

[0026] - The thermostatic assembly further comprises a control mechanism for the temperature of the mixed fluid, this mechanism being carried by the casing and connecting the piston to the casing so as to adjust the position of the piston along the axis.

[0027] - The thermostatic assembly forms a thermostatic cartridge adapted to be fitted in one piece into a tap body.

[0028] The invention will be better understood upon reading the following description, given solely by way of example and made with reference to the drawings in which: - [Fig.1] The [Fig.1] is a longitudinal section of a thermostatic assembly according to the invention, made in the form of a thermostatic cartridge; - [Fig. 2] Fig. 2 is a larger-scale view of the detail in box II on the [Fig.l] ; - [Fig. 3] Fig. 3 is an elevational view of a thermostatic element belonging to the thermostatic assembly of Figures 1 and 2, shown alone; and - [Fig.4] The [Fig.4] is a longitudinal section of the circled detail IV on the [Fig.3]

[0029] Figures 1 and 2 show a thermostatic cartridge 1 arranged around and along an axis XX. This thermostatic cartridge 1 is suitable for equipping a mixer tap to be supplied with hot and cold water, not shown as such in the figures, or, more generally, for equipping an installation supplied with a hot fluid and a cold fluid to be mixed.

[0030] The thermostatic cartridge 1 comprises, as its main external component, a hollow casing 10. This casing 10 is intended to be sealed and mounted within the body of the aforementioned mixer tap.

[0031] The casing 10 internally delimits a chamber 11 which is cylindrical and centered on the XX axis. The hot and cold water to be regulated by the thermostatic cartridge 1 are intended to mix inside chamber 11, forming mixed water.

[0032] For convenience, the rest of the description is oriented with respect to the XX axis, in the sense that the terms "upper" and "top" correspond to an axial orientation turned towards the upper part of figures 1 to 4, while the terms "lower" and "bottom" correspond to an axial direction in the opposite direction.

[0033] In the embodiment shown in the figures, and as clearly visible in Figures 1 and 2, the casing 10 comprises two separate housings, namely a lower housing 12 and an upper housing 13, which are fixedly joined to one another. The chamber 11 is jointly delimited by the lower housing 12 and the upper housing 13, being formed by an internal volume of the upper housing 13 within which the lower housing 12 is arranged in a sealed manner, without the latter completely occupying the aforementioned internal volume. The embodiment of the casing 10, combining here the lower housing 12 and the upper housing 13, is not limiting.

[0034] Whatever its embodiment, the casing 10 has a hot water inlet 14, a cold water inlet 15 and a mixed water outlet 16, each of which connects, separately from each other, the outside of the casing 10 to the chamber 11. The outlet of the hot water inlet 14 in the chamber 11 and the outlet of the cold water inlet 15 in the chamber 11 are axially offset from each other, being separated from each other by a lateral wall 17 of the chamber 11, centered on the axis XX.The embodiment of the hot water inlet 14, the cold water inlet 15 and the mixed water outlet 16 is not limiting as long as the hot water inlet 14 constitutes an inlet through which hot water enters chamber 11 from outside the casing 10, the cold water inlet 15 constitutes an inlet through which cold water enters chamber 11 from outside the casing 10, and the mixed water outlet 16 constitutes an outlet through which the mixed water contained in chamber 11 exits the casing 10.

[0035] In the embodiment shown in the figures, the hot water inlet 14 and the cold water inlet 15 extend from chamber 11 radially to axis XX. The mixed water outlet 16 extends from chamber 11 parallel to axis XX, and is even substantially centered on this axis. Furthermore, the upper casing 13 includes the side wall 17 of chamber 11 and delimits both the hot water inlet 14 and the cold water inlet 15, while the lower casing 12 delimits the mixed water outlet 16.

[0036] The thermostatic cartridge 1 also includes a drawer 20, which is visible on the Figures 1 and 2. The drawer 20 is mounted inside chamber 11 in a movable manner along the axis XX between two extreme positions, namely:

[0037] - an extremely low position, in which a seat 20A of the drawer 20, which is located at a lower axial end of this drawer, is axially supported against a seat 10A of the casing 10, which is located, along the axis XX, substantially at the level of the hot water inlet 14 inside the chamber 11, and

[0038] - an extremely high position, in which a seat 20B of the drawer 20, which is located at an upper axial end of the drawer 20, is supported against a seat 10B of the envelope 10, which is located, along the axis XX, substantially at the level of the outlet of the cold water inlet 15 inside the chamber 11.

[0039] In the embodiment shown in the figures, the seat 10A of the casing 10 is formed by the lower housing 12, more precisely by an upper end edge of the latter, while the seat 10B of the casing is formed by the upper housing 13, more precisely by an internal shoulder of the latter. As for the seats 20A and 20B of the drawer 20, they are formed by the lower and upper end edges, respectively, of the drawer 20.

[0040] In all cases, the axial dimension of the spool 20, separating its opposite seats 20A and 20B, is less than the axial distance separating the seats 10A and 10B of the casing 10. Thus, the seat 20A of the spool 20 and the seat 10A of the casing 10 define between them, along the axis XX, a hot water passage PI into which the hot water inlet 14 opens into the chamber 11. Similarly, the seat 20B of the spool 20 and the seat 10B of the casing 10 define between them, along the axis XX, a cold water passage P2 into which the cold water inlet 15 opens into the chamber 11.

[0041] It is understood that, when the spool 20 is in its lowest position, the spool closes the hot water passage PI and therefore completely closes, except for leaks, the hot water inlet into chamber 11, while simultaneously opening the cold water inlet into this chamber to its maximum via the open cold water passage P2. Conversely, when the spool 20 is in its highest position, the spool closes the cold water passage P2 and therefore completely closes, except for leaks, the cold water inlet into chamber 11, while simultaneously opening the hot water inlet into this chamber to its maximum via the hot water passage PI.Naturally, depending on the position of the spool 20 along the axis XX between these extreme high and low positions, the respective closures of the hot water passage PI and the cold water passage P2 vary inversely, which is equivalent to saying that the quantities of hot and cold water admitted into the chamber 11 are regulated, in inverse proportions, by the spool 20 according to its axial position. In Figures 1 and 2, the spool 20 occupies the extreme high position.

[0042] According to an advantageous arrangement, which is implemented in the embodiment considered here, the hot water passage PI and the cold water passage P2 each run around the axis XX, optionally through 360°. To this end, the seats 10A, 10B, 20A and 20B each run completely around the axis XX. In this way, the distribution of hot and cold water in the hot water passage PI and the cold water passage P2 around the axis XX is improved.

[0043] The drawer 20 is mounted inside the chamber 11 by sealing the hot water inlet 14 and the cold water inlet 15 to each other outside the drawer. For this purpose, in the embodiment considered here, the drawer 20 is provided with a peripheral seal 21, which runs all around the outer side face of the drawer and which is pressed, radially to the axis XX, against the side wall 17 of the chamber 11, so as to form a seal against hot and cold water between the hot water inlets 14 and cold water inlets 15. In addition, so that the cold water admitted into the chamber 11 via the cold water inlet 15 can join and mix with the hot water admitted into the chamber via the hot water inlet 14, to form the mixed water flowing downstream of the drawer 20 to the mixed water outlet 16, the drawer 20 has drainage orifices 22, which are indicated only by dashed lines on the [Fig.2] and which connect the opposite axial faces of the drawer to each other. It should be noted that the features of the drawer 20, such as the seal 21, which allows the hot water 14 and cold water 15 inlets to be sealed against each other outside the drawer, as well as the features of the drawer, such as the drain holes 22, which allow the cold water to flow through the drawer to join the hot water, are not limiting.

[0044] To drive the drawer 20 in translation along the axis XX, the cartridge 1 includes a thermostatic element 30, which is visible in all the figures, being shown alone in Figures 3 and 4. The thermostatic element 30 includes a body 31 and a piston 32, which, in the assembled state of the cartridge 1, are substantially centered on the axis XX, the piston 32 being partially received in the body 31. The thermostatic element 30 is designed so that its body 31 and its piston 32 move relative to each other along the axis XX, this relative movement being controlled by a temperature variation applied to the body 31, which can therefore be described as a thermosensitive body. To this end, the body 31 contains a thermodilatable material 33, which is shown schematically only in [Fig.l] : during its expansion, the thermodilatable material 33 causes the piston 32 to move relative to the body 31, while during its contraction, the thermodilatable material 33 allows the piston to retract relative to the body.

[0045] In order to guide the relative movement along the axis XX between the body 31 and the piston 32, the body 31 includes a guide 34 in which the piston 32 is slidably mounted along the axis XX, while emerging axially from this guide 34. The guide 34 thus forms an upper terminal portion of the body 31. Furthermore, here, the guide 34 has a tubular shape, which is centered on the axis XX and whose inner bore receives the piston 32 in a complementary manner, with a sliding clearance. In practice, the sliding assembly of the piston 32 in the guide 34 is advantageously made smooth by lubricating agents, not visible in the figures, and placed at the interface between the piston 32 and the guide 34.

[0046] In the embodiment shown in the figures, the body 31 also includes a cup 35 extending downwards from the guide 34, thus forming a lower end portion of the body 31. In practice, the guide 34 and the cup 35 are fixedly joined to each other by any suitable means. The cup 35 advantageously contains the thermodilatable material 33, being made of a thermally conductive material, typically metallic. In the assembled state of the cartridge 1, the cup 35 is arranged to be in contact with the mixed water contained in the chamber 11.More generally, whatever the embodiment of the body 31, the latter is arranged to be in contact with the mixed water within the cartridge 1, by being at least partially disposed in the chamber 11 and, where applicable, in the mixed water outlet 16: in this way, the thermodilatable material 33 is thermally sensitized by the mixed water from the chamber 11, so that the relative axial displacement between the body 11 and the piston 32 is controlled by the temperature of this mixed water.

[0047] In all cases, in the assembled state of the cartridge 1, the body 31 is connected to the drawer 20 so as to drive the drawer 20 in movement along the axis XX inside the chamber 11, so that the drawer 20 closes, in inverse proportions, the passages of hot water PI and cold water P2 as explained previously. In the embodiment shown in the figures, the body 31 and the drawer 20 are fixedly joined to each other by screwing, here centered on the axis XX: for this purpose, the guide 34 of the body 31 is externally provided with a thread 36, here centered on the axis XX, while the drawer 20 is internally provided with a tapped hole 23, which is complementary to the thread 34 and which is arranged coaxially in a passage 24 of the drawer 20. The passage 24 passes axially through the drawer 20, being centered on the axis XX, and, in the assembled state of the cartridge 1, internally receives the guide 34 in a complementary manner.In practice, other embodiments than screwing the thread 36 into the tapped hole 23 are conceivable for linking the body 31 and the drawer 20 in movement along the axis XX, in particular by means of cooperation by complementarity of shapes between the guide 34 and the passage 24: as an example, the guide 34 is externally smooth and is received in a complementary way in the internally smooth passage 24, being fixed axially in position relative to the body 31 by a . added component such as a nut, a circlip, etc.

[0048] As regards the piston 32, the latter is, in the assembled state of the cartridge 1, connected to the envelope 10, here by a mechanism 40 acting on the axial position of the piston 32 with respect to the envelope 10, this mechanism 40 being detailed further on.

[0049] Assuming that the mechanism 40 maintains the position of the piston 32 fixed along the axis XX relative to the casing 10, the temperature of the mixed water at the outlet of the cartridge 1 is regulated thermostatically by the spool 20 and the thermostatic element 30. Indeed, in this assumption, the temperature of the mixed water results directly from the respective quantities of hot and cold water admitted into the chamber 11 via respectively the hot water passage PI and the cold water passage P2 more or less obstructed by the spool 20, as explained previously.If the supply of hot and / or cold water to the cartridge is disrupted and, for example, the mixed water temperature rises, the piston 32 extends axially relative to the body 31, causing the body 31 and therefore the spool 20 to move downwards. The proportion of hot water flowing through the hot water passage P1 decreases, while conversely, the proportion of cold water flowing through the cold water passage P2 increases, resulting in a drop in the mixed water temperature. The opposite reaction occurs when the mixed water temperature decreases. A compression spring 50 is provided to bring the body 31 and piston 32 back together, effectively causing the piston 32 to retract into the body 31 during a contraction of the thermodilatable material 33.In the embodiment shown in the figures, this return spring 50 is axially interposed between, on the one hand, the casing 10, here the lower housing 12, and, on the other hand, the body 31, here with an interposed plate. The corrections to the temperature of the mixed water result in a regulating equilibrium for this mixed water temperature, and this at a thermostatic regulating temperature which depends on the position, imposed by the mechanism 40, of the piston 32 along the axis XX.

[0050] The mechanism 40 allows the thermostatic control temperature to be adjusted, thus controlling the mixed water temperature, by acting on the axial position of the piston 32. In the embodiment considered here, the mechanism 40 is supported by the housing 10, here by the upper casing 13, and includes a stop 41, against which the upper end of the piston 32 is axially pressed and which is slidably mounted, along the axis XX, inside a nut 42, with an overtravel spring 43 interposed axially between the stop 41 and the nut 42. The axial position of the nut 42 inside the housing 10, and therefore the height of the stop 41, can be modified by an adjusting screw 44, which is centered on the axis XX and whose upper end emerges from the upper casing 13 in order to be rotationally linked with a control lever, not shown in the figures. At its lower end, The adjusting screw 44 is screwed into the nut 42, the latter being rotationally connected around the axis XX to the upper housing 13, typically by splines. Thus, when the screw 44 is rotated about the axis XX, the nut 42 translates along this axis, which causes the corresponding movement of the stop 41 via the overtravel spring 43, it being noted that this overtravel spring 43 is substantially stiffer than the return spring 50.

[0051] The structure and operation of the adjustment mechanism 40 will not be described further here, it being understood that the reader may refer to FR 2 869 087 for this purpose. It should be noted that the embodiment of this mechanism 40 is not limiting to the invention: other embodiments are known in the art, for example in FR 2 921 709, FR 2 774 740 and FR 2 870 611. Furthermore, as an alternative not shown, if the ability to adjust the temperature at which the slide 20 regulates the mixing of hot and cold water is waived, the mechanism 40 can be removed from the thermostatic cartridge 1, the piston 32 then being fixedly connected to the casing 10.

[0052] Returning now to the description of the thermostatic element 30, it should be noted that the latter includes a sealing sleeve 37 which, as clearly visible in Figures 1 to 4, is coaxially positioned around both the guide 34 of the body 31 and the piston 32 of the thermostatic element 30, so as to seal the sliding assembly of the piston 32 in the guide 34. The sealing sleeve 37 thus prevents the mixed water contained in the chamber 11, as well as any particles potentially present in this mixed water, such as limescale particles, from entering the thermostatic element 30 and reaching the sliding assembly of the piston 32 in the guide 34, at the risk of damaging this sliding assembly. The sealing sleeve 37 also prevents the aforementioned lubricating agents from escaping from the thermostatic element 30, by escaping from the sliding assembly of the piston 32 in the guide 34.

[0053] The sealing sleeve 37 has an overall tubular shape, which is substantially centered on the axis XX and runs continuously around the axis XX. As shown in [Fig.4], the sealing sleeve 37 thus includes three distinct tubular parts along the axis XX, namely a lower part 37.1 and an upper part 37.2, which are opposite each other along the axis XX, as well as an intermediate part 37.3 which connects the lower part 37.1 and upper part 37.2.

[0054] The lower portion 37.1 is fixedly connected to the guide 34 along the axis XX by any suitable means. In the embodiment shown in the figures, the guide 34 is externally provided with a peripheral groove 38 in which the lower portion 37.1 of the sealing sleeve 37 is fitted to be fixedly connected along the axis XX this lower part 37.1 to the guide 34. Of course, other forms of embodiment are conceivable as long as the sealing sleeve 37 is, by its lower part 37.1, fixedly linked to the guide 34 along the axis XX.

[0055] The upper portion 37.2 of the sealing sleeve 37 is applied against the piston 32 all around the axis XX in sliding contact along this axis. In the embodiment shown in the figures, the upper portion 37.2 of the sealing sleeve 37 forms a ring that is tightly fitted all around the piston 32, in particular by being tightly fitted all around the piston 32, while allowing relative axial sliding between this ring and the piston 32. Of course, other embodiments are conceivable as long as the sealing sleeve 37 is, by its upper portion 37.2, applied in contact, both tight and sliding along the axis XX, with the piston 32 all around the axis XX. During the movement of the piston 32 relative to the body 31, and in both possible opposite directions, the piston 32 slides against the upper part 37.2, without changing the axial position of this upper part 37.2 in relation to envelope 10, nor modify the total axial dimension of the sealing sleeve 37. .

[0056] According to a particularly advantageous arrangement which improves the sealing performance at the level of the upper part 37.2 of the sealing sleeve 37, this upper part 37.2 is applied against the piston 32 substantially radially to the axis XX by the elastic resilience effect of the sealing sleeve 37, in particular its intermediate part 37.3. For this purpose, the sealing sleeve 37 has an elasticity which tends to make the sealing sleeve return to its rest shape, so that by subjecting the upper part 37.2 to a radial stress oriented opposite to the axis XX by the presence of the piston 32 arranged coaxially through the upper part 37.2, the sealing sleeve 37, in particular its intermediate part 37.3, generates by elasticity an opposing radial stress which presses the upper part 37.2 against the piston 32.For this purpose, the sealing sleeve 37 is, for example, made of an elastomeric material, such as rubber or EPDM.

[0057] According to another particularly advantageous arrangement, which can be combined with the above, the piston 32 is externally smooth over at least its entire upper portion that emerges from the guide 34 when the piston 32 is fully extended relative to the body 31. In practice, it is possible to make the piston externally smooth over its entire axial dimension. The piston 32 then has the advantage of being inexpensive and easy to assemble to the rest of the thermostatic element 30.

[0058] Without compromising its sealing performance with respect to the sliding mounting of the piston 32 in the guide 34, the sealing sleeve 37 is advantageously dimensioned in a compact manner, both transversely to the axis XX and along this axis XX.

[0059] Thus, with regard to the dimensioning, transverse to the axis XX, of the sealing sleeve 37, the maximum outside diameter of the sealing sleeve 37, denoted D37 in [Fig. 2], is advantageously smaller than the minimum inside diameter of the passage 24, denoted D24. In the embodiment shown in the figures, this implies that the maximum outside diameter D37 of the sealing sleeve 37 is smaller than the diameter of the crest of the threaded hole 23 in the passage 24. In this way, the insertion of the guide 34 into the passage 24 during the assembly of the cartridge 1 is possible while leaving the sealing sleeve 37 in place on the guide 34 and the piston 32. In particular, it is then not necessary to partially or completely disengage the sealing sleeve 37, or, where applicable, also remove the piston 32, to assemble the slide 20 and the thermostatic element 30.

[0060] With regard to the axial dimensioning of the sealing sleeve 37, the total axial dimension of the sealing sleeve 37 is advantageously limited as much as possible, in particular to prevent the sealing sleeve 37 from occupying a substantial space in the chamber 11, which would impede the flow of water and limit the maximum permissible flow rate through the cartridge 1. To this end, according to a first advantageous dimensional aspect, the upper part 37.2 of the sealing sleeve 37 is axially juxtaposed with the guide 34, as can be clearly seen in [Fig. 4]: in other words, the upper part 37.2 of the sealing sleeve covers the upper end of the guide 34, directly covering the upper end edge of the guide 34, with only an axial clearance. According to a second advantageous dimensional aspect, the maximum axial dimension of the sealing sleeve 37, denoted L37 in [Fig. 4], is limited to a certain axial clearance.4], is less than the maximum outside diameter, denoted D34, of the region of the guide 34, by which the lower part 37.1 of the sealing sleeve 37 is fixed to the guide 34. .

[0061] Following on from the preceding considerations regarding the axial compactness of the sealing sleeve 37, an additional advantage concerns the piston 32, in that, somewhat similarly to the sealing sleeve 37, the upper terminal portion of the piston 32 can be axially dimensioned. It is then the thermostatic element 30, considered as a whole, that proves to be particularly compact along the axis XX. To this end, it is advantageously provided that, when the piston 32 is fully retracted into the body 31, the piston 32 protrudes axially from the sealing sleeve 37 over a non-zero axial extent, denoted e32 in [Fig. 3], which is less than or equal to one millimeter. In this way, the risk of the piston 32 jamming in the guide 34 is significantly reduced.

[0062] Finally, various modifications and variations to the thermostatic cartridge 1 described so far are also conceivable. By way of example:

[0063] - materials other than those mentioned above are conceivable for the sealing sleeve 37, for example silicone; and / or

[0064] - rather than the casing 10, the drawer 20, the thermostatic element 30 and the spring of return 50, as well as, where applicable, the mechanism 40, are assembled together in the form of a thermostatic cartridge capable of being brought together in one piece into a tap body, such as the thermostatic cartridge 1 envisaged so far, the slide 20 and the thermostatic element 30, as well as, where applicable, the mechanism 40 and the return spring 50, can be installed directly into a tap body, the latter then forming an envelope functionally similar to the envelope 10.

Claims

Claims

1. Thermostatic assembly (1), comprising: - an envelope (10) in which are delimited: - a chamber (11), which defines an axis (XX) and in which a hot fluid and a cold fluid mix to form a mixed fluid, - a hot fluid inlet (14) through which the hot fluid enters the chamber (11) from outside the casing (10), - a cold fluid inlet (15) through which the cold fluid enters the chamber (11) from outside the casing (10), and - a mixed fluid outlet (16) through which the mixed fluid contained in the chamber (11) leaves the casing (10), - a slide (20) for regulating the temperature of the mixed fluid, the slide being movable along the axis (XX) inside the chamber (11) so as to close, in respective inverse proportions, a hot fluid passage (PI) and a cold fluid passage (P2) which are each delimited axially between the slide (20) and the casing (10), the hot fluid passage (PI) being supplied by the hot fluid coming from the hot fluid inlet (14) while the cold fluid passage (P2) is supplied by the cold fluid coming from the cold fluid inlet (15), and - a thermostatic element (30) which comprises: - a body (31), which contains a thermo-expandable material (33) and which is at least partially arranged in the chamber (11) to be in contact with the mixed fluid and to be connected to the slide (20) so as to cause the slide to move along the axis (XX) inside the chamber, - a piston (32), which is connected to the casing (10) by being centered on the axis (XX) and which is partially received in the body (31) in a movable manner along the axis (XX) under the action of the thermodilatable material (33) during an expansion of the thermodilatable material, the piston being mounted sliding along the axis in a guide (34) of the body (31), from which the piston emerges outside the body, and - a sealing sleeve (37), which is coaxially attached around the guide (34) and the piston (32) so as to seal the sliding mounting of the piston in the guide, which sealing sleeve (37) includes a first part (37.1), which is fixedly connected to the guide (34) along the axis (XX), and a second part (37.2) which is applied against the piston all around the axis in sliding contact along the axis.

2. Thermostatic assembly according to claim 1, in which the slide (20) is provided with a passage (24), which passes axially through the slide from one side to the other, being centered on the axis (XX), and which receives the guide (34) in a complementary manner, and in which the maximum external diameter (D37) of the sealing sleeve (37) is less than the minimum internal diameter (D24) of the passage (24).

3. Thermostatic assembly according to claim 2, in which the guide (34) and the passage (24) cooperate by complementarity of shapes to link in movement along the axis (XX) the body (31) and the drawer (20).

4. Thermostatic assembly according to one of claims 2 or 3, in which the body (31) and the slide (20) are fixedly secured to each other by screwing a thread (36) of the guide (34) into a tapping (23) of the passage (24).

5. Thermostatic assembly according to any one of the preceding claims, in which the second part (37.2) of the sealing sleeve (37) is axially juxtaposed to the guide (34).

6. Thermostatic assembly according to any one of the preceding claims, in which the maximum axial dimension (L37) of the sealing sleeve (37) is less than the maximum external diameter (D34) of the region of the guide (34), by which the first part (37.1) of the sealing sleeve is fixed along the axis (XX) to the guide (34).

7. Thermostatic assembly according to any one of the preceding claims, in which, when the piston (32) is retracted as far as possible into the body (31), the piston emerges axially from the sealing sleeve (37) over an axial extent (e32) which is less than or equal to one millimeter.

8. Thermostatic assembly according to any one of the preceding claims, in which the second part (37.2) of the sealing sleeve (37) is applied against the piston (32) substantially radially to the axis (XX) by elastic resilience effect of the sealing membrane.

9. A thermostatic assembly according to any preceding claim, wherein the piston (32) is externally smooth over at least all of its portion which emerges from the guide (34) when the piston is deployed to the maximum in relation to the body (31).

10. Thermostatic assembly according to any one of the preceding claims, in which the thermostatic assembly (1) further comprises a mechanism (40) for controlling the temperature of the mixed fluid, this mechanism (40) being carried by the casing (10) and connecting the piston (32) to the casing so as to adjust the position of the piston along the axis (XX).

11. A thermostatic assembly according to any preceding claim, wherein the thermostatic assembly forms a thermostatic cartridge (1) adapted to be fitted integrally into a tap body.

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