EP0781970A1 - Thermostatic expansion valve for air conditioning circuit, especially of motor vehicle - Google Patents

Thermostatic expansion valve for air conditioning circuit, especially of motor vehicle Download PDF

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Publication number
EP0781970A1
EP0781970A1 EP96120353A EP96120353A EP0781970A1 EP 0781970 A1 EP0781970 A1 EP 0781970A1 EP 96120353 A EP96120353 A EP 96120353A EP 96120353 A EP96120353 A EP 96120353A EP 0781970 A1 EP0781970 A1 EP 0781970A1
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EP
European Patent Office
Prior art keywords
cap
expansion valve
thermostatic expansion
thermostatic
bore
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP96120353A
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German (de)
French (fr)
Inventor
Guy Montaille
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Valeo Climatisation SA
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Valeo Climatisation SA
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Filing date
Publication date
Application filed by Valeo Climatisation SA filed Critical Valeo Climatisation SA
Publication of EP0781970A1 publication Critical patent/EP0781970A1/en
Withdrawn legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B41/00—Fluid-circulation arrangements
    • F25B41/30—Expansion means; Dispositions thereof
    • F25B41/31—Expansion valves
    • F25B41/33—Expansion valves with the valve member being actuated by the fluid pressure, e.g. by the pressure of the refrigerant
    • F25B41/335—Expansion valves with the valve member being actuated by the fluid pressure, e.g. by the pressure of the refrigerant via diaphragms
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2341/00—Details of ejectors not being used as compression device; Details of flow restrictors or expansion valves
    • F25B2341/06—Details of flow restrictors or expansion valves
    • F25B2341/068—Expansion valves combined with a sensor
    • F25B2341/0683—Expansion valves combined with a sensor the sensor is disposed in the suction line and influenced by the temperature or the pressure of the suction gas

Definitions

  • the invention relates to a thermostatic expansion valve suitable for being part of an air conditioning circuit which can be used, for example, in a motor vehicle air conditioning installation.
  • the thermostatic expansion valve of the invention is of the type comprising a metal body traversed by a first duct controlled by an adjustable valve and by a second duct housing a thermostatic sensor controlling the valve, and in which the thermostatic sensor is held by a cap housed in a body bore.
  • thermostatic expansion valve is intended to be part of an air conditioning circuit traversed by a refrigerant and further comprising a compressor, a condenser and an evaporator.
  • the first conduit is then connected between the outlet of the condenser and the inlet of the evaporator to cause a drop in pressure of the refrigerant in liquid phase and under high pressure from the condenser and to obtain a refrigerant in vapor phase and in liquid phase at low pressure sent to the evaporator.
  • the second conduit is connected between the outlet of the evaporator and the inlet of the compressor so as to be traversed by the refrigerant, in vapor phase at low pressure, which comes from the evaporator and which is sent to the compressor.
  • the valve is opened more or less depending on various parameters, namely the pressure of the thermostatic sensor (which depends in particular on the temperature of the evaporated refrigerant), the pressure of the evaporator and the pressure of an antagonistic spring acting on the valve.
  • the metal body of a thermostatic expansion valve of this type is usually produced in the form of a solid block, generally made of aluminum, machined to form the respective inlets and outlets of the first and second ducts and to further form an internal housing to receive the thermostatic sensor as well as various components linked to the valve.
  • the cap used to hold the thermostatic sensor is held by a retaining ring of the "circlip" type engaged in an annular peripheral groove machined at the periphery of the aforementioned bore.
  • this cap is located between the second duct through which the refrigerant in vapor phase and at low pressure, on the one hand, and the external medium, on the other hand, condensation forms due to an exchange of temperature.
  • This condensation can cause corrosion of the retaining ring and can therefore lead to the release of the cap and failure of the regulator.
  • the object of the invention is in particular to overcome the aforementioned drawbacks.
  • thermostatic expansion valve of the type defined in the introduction, in which the cap is held in position by crimping points formed in the metal body at the periphery of the bore and bearing on the periphery of the cap.
  • the maintenance of the cap is ensured by crimping points formed in the metal body itself and not by a retaining ring as in the prior art, which makes it possible to reduce the overall cost of the regulator.
  • the crimp points are preferably regularly spaced around the periphery of the bore.
  • the regulator comprises four crimping points arranged at 90 ° from each other relative to the center of the bore.
  • the body of the thermostatic expansion valve is advantageously made of aluminum or an aluminum-based alloy.
  • the cap it is advantageously made of aluminum or aluminum alloy, or else of copper or of a copper-based alloy, such as brass.
  • an O-ring seal is interposed between the cap and the bore of the metal body.
  • FIG. 1 shows a thermostatic expansion valve D part of an air conditioning circuit which further comprises a compressor CP, a condenser CD and an evaporator E, these various components being traversed by a refrigerant in the direction indicated by the arrows.
  • the thermostatic expansion valve D comprises a metal body 10 produced in the form of a solid block of substantially parallelepiped shape, for example of aluminum.
  • This body comprises an inlet 12 suitable for being connected to the outlet of the condenser CD and an opposite outlet 14 suitable for being connected to the inlet of the evaporator E.
  • the inlet 12 and the outlet 14 constitute the two ends of a first conduit forming expansion chamber and the passage of which is controlled by a valve 16 here constituted by a ball movable along an axis XX.
  • the valve 16 is disposed in a valve body 18 placed in an axial housing 20 which extends on the axis XX and which opens out by a circular bore 22 on an upper face 24 of the body 10.
  • the valve body 18 includes an axial passage 26 and a transverse passage 28 which communicate between them the inlet 12 and the outlet 14.
  • the aforementioned passages 26 and 28 communicate with the inlets 12 and 14 by different bores of known structures, not described in detail.
  • the valve 16 is biased towards a valve seat 30 by means of a helical spring 32 interposed between a valve support 34 and an adjustment screw 36 for adjusting the pressure of the spring which acts on the valve 16 in the closing direction.
  • the valve body 18 is held inside the bore 20 by two O-rings 38 and 40, arranged on either side of the transverse passage 28.
  • the valve 16 undergoes the antagonistic action of a rod 42 forming a pusher which extends in the direction of the axis XX.
  • This rod is guided in the valve body 18 successively by an O-ring 44, a washer 46, a spring 48 and a ring 50.
  • the rod 42 is biased by a diaphragm 52 via a disc 54.
  • This diaphragm 52 is part of a thermostatic sensor 56, also called a "bulb", which is located in a conduit the two ends of which are respectively formed by an inlet 58 connected to the outlet of the evaporator E and an outlet 60 connected to the inlet of the compressor CP.
  • the sensor 56 comprises a lower cup bearing on the valve body 18 and an upper cup 64. These two cups hold together the diaphragm 52 and a retaining member 66.
  • the upper cup 64 has, at its top, an axial passage 68 in which a capillary tube 70 is engaged.
  • the thermostatic sensor 56 internally houses a gas and also contains activated carbon 72.
  • On the top of the upper cup 64 is supported a sleeve 74, one end of which engages in a blind hole 76 formed in a cap 78 of circular shape.
  • This cap 78 is housed in the aforementioned bore 22 with the interposition of an O-ring seal 80 engaged in a peripheral groove 82 of said cap 78.
  • the latter is formed from a metallic material, for example aluminum, an aluminum alloy, copper or a copper alloy.
  • thermostatic expansion valve As described above, is generally known.
  • the cap 78 is held in its housing, that is to say in the bore 22, by four crimping points 84 ( Figures 1 and 2) formed directly in the material of the body 10 at the periphery of the bore. These four crimp points are regularly spaced and arranged at 90 ° from each other with respect to the center of the bore, as can be seen in FIG. 2. These four bore points project radially towards the center of the cap. (axis XX) and rest on the circumference of the cap to hold it in position. These crimping points can be obtained by suitable tools, in particular by hammering or hammering tools.
  • the four crimping points can be formed either successively or preferably simultaneously, using the same tool which is actuated in the direction of the axis XX to deform the material of the body 10 and obtain the crimping points.
  • the refrigerant in the vapor phase is compressed by the compressor CP and sent to the condenser CD where it condenses in the liquid phase under high pressure.
  • the refrigerant is then expanded in the regulator D under the action of the valve 16 to give a mixture in liquid phase and in vapor phase under low pressure. This is then sent to the evaporator and leaves it in the vapor phase under low pressure.
  • the vapor phase fluid then passes through the second conduit between the ends 58 and 60 by acting on the thermostatic sensor 56, before returning to the compressor CP.
  • the condenser CD is crossed by an air flow which is heated on contact with it, while the evaporator E is crossed by an air flow which is cooled on contact with it and which is intended to serve, in the example, the air conditioning of a motor vehicle.
  • the regulator D creates a pressure drop in the liquid phase refrigerant which passes through the body 10 between the inlet 12 and the outlet 14. As the liquid is incompressible, the regulator D maintains the "overheating" which ensures the gaseous state refrigerant at the inlet of the CP compressor.
  • the expansion valve D controls the flow rate of the refrigerant as a function of the heat load absorbed by the evaporator E, which varies according to the different operating conditions. Thus, only the necessary quantity of refrigerant is injected for maximum use of the exchange surface.
  • the temperature at the thermostatic sensor 56 (bulb) increases, the pressure P1 rises and causes an increase in opening. The same is true for a pressure drop P2 in the evaporator. On the other hand, a drop in temperature at the thermostatic sensor 56 and a rise in pressure in the evaporator E act in the closing direction.
  • condensation tends to form, by temperature exchange, outside the cap 78.
  • this cap is here held by crimping points formed directly in the material of the body 10, in the example aluminum, it will not corrode and allow the cap to escape and lead to a detector failure.
  • thermostatic detector of the invention is intended to be used mainly in air conditioning installations of motor vehicles.

Abstract

The thermostatic regulator has a either an aluminium or aluminium based body or copper based body (10) through which passes a first pipe(12,14), controlled by an adjustable valve(16). A second pipe(58,60) is fitted a thermostat sensor(56) which drives the valve(16). The sensor(56) is fixed in place by a cap(78) located in a circular slot(22) in the body(10). The cap(78) is maintained in position by four clamping points(84) made by deforming the soft metal in the body(10) at the edges of the circular slot(22) so that they press against the upper surface of the cap(78). A seal(80) is fitted between the cap(78) and the circular slot(22).

Description

L'invention concerne un détendeur thermostatique propre à faire partie d'un circuit de climatisation pouvant être utilisé, par exemple, dans une installation de climatisation de véhicule automobile.The invention relates to a thermostatic expansion valve suitable for being part of an air conditioning circuit which can be used, for example, in a motor vehicle air conditioning installation.

Le détendeur thermostatique de l'invention est du type comprenant un corps métallique traversé par un premier conduit contrôlé par un clapet réglable et par un second conduit logeant un capteur thermostatique pilotant le clapet, et dans lequel le capteur thermostatique est maintenu par un capuchon logé dans un alésage du corps.The thermostatic expansion valve of the invention is of the type comprising a metal body traversed by a first duct controlled by an adjustable valve and by a second duct housing a thermostatic sensor controlling the valve, and in which the thermostatic sensor is held by a cap housed in a body bore.

Un tel détendeur thermostatique est destiné à faire partie d'un circuit de climatisation parcouru par un fluide frigorigène et comprenant en outre un compresseur, un condenseur et un évaporateur.Such a thermostatic expansion valve is intended to be part of an air conditioning circuit traversed by a refrigerant and further comprising a compressor, a condenser and an evaporator.

Le premier conduit est alors relié entre la sortie du condenseur et l'entrée de l'évaporateur pour provoquer une chute de pression du fluide frigorigène en phase liquide et sous haute pression issu du condenseur et obtenir un fluide frigorigène en phase vapeur et en phase liquide à basse pression envoyé à l'évaporateur.The first conduit is then connected between the outlet of the condenser and the inlet of the evaporator to cause a drop in pressure of the refrigerant in liquid phase and under high pressure from the condenser and to obtain a refrigerant in vapor phase and in liquid phase at low pressure sent to the evaporator.

De son côté, le second conduit est relié entre la sortie de l'évaporateur et l'entrée du compresseur de manière à être traversé par le fluide frigorigène, en phase vapeur à basse pression, qui est issu de l'évaporateur et qui est envoyé au compresseur.For its part, the second conduit is connected between the outlet of the evaporator and the inlet of the compressor so as to be traversed by the refrigerant, in vapor phase at low pressure, which comes from the evaporator and which is sent to the compressor.

Le clapet est ouvert plus ou moins en fonction de différents paramètres, à savoir la pression du capteur thermostatique (qui dépend notamment de la température du fluide frigorigène évaporé), la pression de l'évaporateur et la pression d'un ressort antagoniste agissant sur le clapet.The valve is opened more or less depending on various parameters, namely the pressure of the thermostatic sensor (which depends in particular on the temperature of the evaporated refrigerant), the pressure of the evaporator and the pressure of an antagonistic spring acting on the valve.

Le corps métallique d'un détendeur thermostatique de ce type est réalisé habituellement sous la forme d'un bloc massif, généralement en aluminium, usiné pour former les entrées et sorties respectives du premier et du second conduit et pour former en outre un logement interne destiné à recevoir le capteur thermostatique ainsi que différents composants liés au clapet.The metal body of a thermostatic expansion valve of this type is usually produced in the form of a solid block, generally made of aluminum, machined to form the respective inlets and outlets of the first and second ducts and to further form an internal housing to receive the thermostatic sensor as well as various components linked to the valve.

Dans les dispositifs connus de ce type, le capuchon servant au maintien du capteur thermostatique est maintenu par un anneau de retenue du type "circlip" engagé dans une gorge périphérique annulaire usinée à la périphérie de l'alésage précité.In known devices of this type, the cap used to hold the thermostatic sensor is held by a retaining ring of the "circlip" type engaged in an annular peripheral groove machined at the periphery of the aforementioned bore.

Toutefois, comme ce capuchon se trouve situé entre le second conduit traversé par le fluide frigorigène en phase vapeur et à basse pression, d'une part, et le milieu extérieur, d'autre part, il se forme une condensation due à un échange de température.However, as this cap is located between the second duct through which the refrigerant in vapor phase and at low pressure, on the one hand, and the external medium, on the other hand, condensation forms due to an exchange of temperature.

Cette condensation peut provoquer une corrosion de l'anneau de retenue et peut donc conduire à la sortie du capuchon et à une défaillance de fonctionnement du détendeur.This condensation can cause corrosion of the retaining ring and can therefore lead to the release of the cap and failure of the regulator.

Pour éviter cet inconvénient il est nécessaire d'utiliser un anneau de retenue en matériau inoxydable, donc coûteux.To avoid this drawback, it is necessary to use a retaining ring made of stainless material, which is therefore expensive.

Au surplus, la mise en place d'un tel anneau de retenue nécessite un outillage particulier qui n'est pas toujours compatible avec les chaînes de fabrication automatisées.In addition, the installation of such a retaining ring requires special tools which are not always compatible with automated production lines.

Enfin, la présence de cet anneau de retenue nuit à une bonne intégration du capuchon dans le corps métallique.Finally, the presence of this retaining ring affects good integration of the cap into the metal body.

L'invention a notamment pour but de surmonter les inconvénients précités.The object of the invention is in particular to overcome the aforementioned drawbacks.

Elle propose à cet effet un détendeur thermostatique du type défini en introduction, dans lequel le capuchon est maintenu en position par des points de sertissage formés dans le corps métallique à la périphérie de l'alésage et prenant appui sur le pourtour du capuchon.To this end, it offers a thermostatic expansion valve of the type defined in the introduction, in which the cap is held in position by crimping points formed in the metal body at the periphery of the bore and bearing on the periphery of the cap.

Ainsi, le maintien du capuchon est assuré par des points de sertissage formés dans le corps métallique lui-même et non pas par un anneau de retenue comme dans la technique antérieure, ce qui permet de diminuer le coût global du détendeur.Thus, the maintenance of the cap is ensured by crimping points formed in the metal body itself and not by a retaining ring as in the prior art, which makes it possible to reduce the overall cost of the regulator.

De tels points de sertissage ne sont pas sensibles à la corrosion et ne risquent pas de conduire à une sortie accidentelle du capuchon et à une défaillance du détendeur thermostatique.Such crimping points are not susceptible to corrosion and are unlikely to lead to accidental release of the cap and failure of the thermostatic expansion valve.

En outre, la réalisation de ces points de sertissage est particulièrement aisée.In addition, the realization of these crimping points is particularly easy.

Les points de sertissage sont de préférence régulièrement espacés à la périphérie de l'alésage.The crimp points are preferably regularly spaced around the periphery of the bore.

Dans une forme de réalisation préférée de l'invention, le détendeur comprend quatre points de sertissage disposés à 90° les uns des autres par rapport au centre de l'alésage.In a preferred embodiment of the invention, the regulator comprises four crimping points arranged at 90 ° from each other relative to the center of the bore.

Ces points de sertissage sont avantageusement obtenus par matage ou martelage, c'est-à-dire par façonnage à l'aide d'un outil du type marteau.These crimping points are advantageously obtained by hammering or hammering, that is to say by shaping using a hammer-type tool.

Le corps du détendeur thermostatique est avantageusement réalisé en aluminium ou en alliage à base d'aluminium.The body of the thermostatic expansion valve is advantageously made of aluminum or an aluminum-based alloy.

Quant au capuchon, il est avantageusement réalisé en aluminium ou alliage d'aluminium, ou encore en cuivre ou en alliage à base de cuivre, tel que du laiton.As for the cap, it is advantageously made of aluminum or aluminum alloy, or else of copper or of a copper-based alloy, such as brass.

Selon une autre caractéristique de l'invention, un joint d'étanchéité torique est interposé entre le capuchon et l'alésage du corps métallique.According to another characteristic of the invention, an O-ring seal is interposed between the cap and the bore of the metal body.

Dans la description qui suit, faite à titre d'exemple, on se réfère au dessin annexé, sur lequel :

  • la figure 1 représente une vue en coupe d'un détendeur thermostatique selon l'invention, ainsi que les différents composants d'un circuit de climatisation; et
  • la figure 2 est une vue de dessus, à échelle réduite, du détendeur thermostatique représenté à la figure 1.
In the description which follows, given by way of example, reference is made to the appended drawing, in which:
  • Figure 1 shows a sectional view of a thermostatic expansion valve according to the invention, as well as the various components of an air conditioning circuit; and
  • FIG. 2 is a top view, on a reduced scale, of the thermostatic expansion valve shown in FIG. 1.

La figure 1 montre un détendeur thermostatique D faisant partie d'un circuit de climatisation qui comprend en outre un compresseur CP, un condenseur CD et un évaporateur E, ces différents composants étant parcourus par un fluide frigorigène dans la direction indiquée par les flèches.Figure 1 shows a thermostatic expansion valve D part of an air conditioning circuit which further comprises a compressor CP, a condenser CD and an evaporator E, these various components being traversed by a refrigerant in the direction indicated by the arrows.

Le détendeur thermostatique D comprend un corps métallique 10 réalisé sous la forme d'un bloc massif de forme sensiblement parallélépipédique, par exemple en aluminium. Ce corps comprend une entrée 12 propre à être reliée à la sortie du condenseur CD et une sortie opposée 14 propre à être reliée à l'entrée de l'évaporateur E. L'entrée 12 et la sortie 14 constituent les deux extrémités d'un premier conduit formant chambre de détente et dont le passage est contrôlé par un clapet 16 constitué ici par une bille déplaçable suivant un axe XX. Le clapet 16 est disposé dans un corps de clapet 18 placé dans un logement axial 20 qui s'étend sur l'axe XX et qui débouche par un alésage circulaire 22 sur une face supérieure 24 du corps 10.The thermostatic expansion valve D comprises a metal body 10 produced in the form of a solid block of substantially parallelepiped shape, for example of aluminum. This body comprises an inlet 12 suitable for being connected to the outlet of the condenser CD and an opposite outlet 14 suitable for being connected to the inlet of the evaporator E. The inlet 12 and the outlet 14 constitute the two ends of a first conduit forming expansion chamber and the passage of which is controlled by a valve 16 here constituted by a ball movable along an axis XX. The valve 16 is disposed in a valve body 18 placed in an axial housing 20 which extends on the axis XX and which opens out by a circular bore 22 on an upper face 24 of the body 10.

Le corps de clapet 18 comprend un passage axial 26 et un passage transversal 28 qui font communiquer entre elles l'entrée 12 et la sortie 14. Les passages 26 et 28 précités communiquent avec les entrées 12 et 14 par différents alésages de structures connues, non décrits en détail. Le clapet 16 est sollicité en direction d'un siège de clapet 30 par l'intermédiaire d'un ressort hélicoïdal 32 interposé entre un support de clapet 34 et une vis de réglage 36 permettant de régler la pression du ressort qui agit sur le clapet 16 dans le sens de la fermeture.The valve body 18 includes an axial passage 26 and a transverse passage 28 which communicate between them the inlet 12 and the outlet 14. The aforementioned passages 26 and 28 communicate with the inlets 12 and 14 by different bores of known structures, not described in detail. The valve 16 is biased towards a valve seat 30 by means of a helical spring 32 interposed between a valve support 34 and an adjustment screw 36 for adjusting the pressure of the spring which acts on the valve 16 in the closing direction.

Le corps de clapet 18 est maintenu à l'intérieur de l'alésage 20 par deux joints toriques 38 et 40, disposés de part et d'autre du passage transversal 28.The valve body 18 is held inside the bore 20 by two O-rings 38 and 40, arranged on either side of the transverse passage 28.

Le clapet 16 subit l'action antagoniste d'une tige 42 formant poussoir qui s'étend dans la direction de l'axe XX. Cette tige est guidée dans le corps de clapet 18 successivement par un joint torique 44, une rondelle 46, un ressort 48 et une bague 50.The valve 16 undergoes the antagonistic action of a rod 42 forming a pusher which extends in the direction of the axis XX. This rod is guided in the valve body 18 successively by an O-ring 44, a washer 46, a spring 48 and a ring 50.

Du côté opposé au clapet 16, la tige 42 est sollicitée par un diaphragme 52 par l'intermédiaire d'un disque 54. Ce diaphragme 52 fait partie d'un capteur thermostatique 56, encore appelé "bulbe", qui est situé dans un conduit dont les deux extrémités sont formée respectivement par une entrée 58 reliée à la sortie de l'évaporateur E et une sortie 60 reliée à l'entrée du compresseur CP. Le capteur 56 comprend une coupelle inférieure prenant appui sur le corps de clapet 18 et une coupelle supérieure 64. Ces deux coupelles maintiennent entre elles le diaphragme 52 et un organe de retenue 66.On the side opposite to the valve 16, the rod 42 is biased by a diaphragm 52 via a disc 54. This diaphragm 52 is part of a thermostatic sensor 56, also called a "bulb", which is located in a conduit the two ends of which are respectively formed by an inlet 58 connected to the outlet of the evaporator E and an outlet 60 connected to the inlet of the compressor CP. The sensor 56 comprises a lower cup bearing on the valve body 18 and an upper cup 64. These two cups hold together the diaphragm 52 and a retaining member 66.

La coupelle supérieure 64 comporte, à son sommet, un passage axial 68 dans lequel est engagé un tube capillaire 70. Le capteur thermostatique 56 loge intérieurement un gaz et contient aussi du charbon actif 72. Sur le sommet de la coupelle supérieure 64 prend appui un manchon 74 dont une extrémité s'engage dans un trou borgne 76 ménagé dans un capuchon 78 de forme circulaire. Ce capuchon 78 est logé dans l'alésage 22 précité avec interposition d'un joint torique d'étanchéité 80 engagé dans une gorge périphérique 82 dudit capuchon 78. Celui-ci est formé d'un matériau métallique, par exemple de l'aluminium, un alliage d'aluminium, du cuivre ou un alliage de cuivre.The upper cup 64 has, at its top, an axial passage 68 in which a capillary tube 70 is engaged. The thermostatic sensor 56 internally houses a gas and also contains activated carbon 72. On the top of the upper cup 64 is supported a sleeve 74, one end of which engages in a blind hole 76 formed in a cap 78 of circular shape. This cap 78 is housed in the aforementioned bore 22 with the interposition of an O-ring seal 80 engaged in a peripheral groove 82 of said cap 78. The latter is formed from a metallic material, for example aluminum, an aluminum alloy, copper or a copper alloy.

La structure générale du détendeur thermostatique, telle qu'elle vient d'être décrite jusqu'à présent, est généralement connue.The general structure of the thermostatic expansion valve, as described above, is generally known.

Conformément à l'invention, le capuchon 78 est maintenu dans son logement, c'est-à-dire dans l'alésage 22, par quatre points de sertissage 84 (figures 1 et 2) formés directement dans le matériau du corps 10 à la périphérie de l'alésage. Ces quatre points de sertissage sont régulièrement espacés et disposés à 90° les uns des autres par rapport au centre de l'alésage, comme on le voit sur la figure 2. Ces quatre points d'alésage font saillie radialement en direction du centre du capuchon (axe XX) et prennent appui sur le pourtour du capuchon pour le maintenir en position. Ces points de sertissage peuvent être obtenus par des outils appropriés, en particulier par des outils de matage ou de martelage du type marteau.According to the invention, the cap 78 is held in its housing, that is to say in the bore 22, by four crimping points 84 (Figures 1 and 2) formed directly in the material of the body 10 at the periphery of the bore. These four crimp points are regularly spaced and arranged at 90 ° from each other with respect to the center of the bore, as can be seen in FIG. 2. These four bore points project radially towards the center of the cap. (axis XX) and rest on the circumference of the cap to hold it in position. These crimping points can be obtained by suitable tools, in particular by hammering or hammering tools.

Les quatre points de sertissage peuvent être formés soit successivement, soit de préférence simultanément, à l'aide d'un même outil qui est actionné dans la direction de l'axe XX pour déformer le matériau du corps 10 et obtenir les points de sertissage.The four crimping points can be formed either successively or preferably simultaneously, using the same tool which is actuated in the direction of the axis XX to deform the material of the body 10 and obtain the crimping points.

On rappellera maintenant le fonctionnement du circuit de climatisation de la figure 1.We will now recall the operation of the air conditioning circuit of Figure 1.

Le fluide frigorigène en phase vapeur est comprimé par le compresseur CP et envoyé dans le condenseur CD où il se condense en phase liquide sous haute pression.The refrigerant in the vapor phase is compressed by the compressor CP and sent to the condenser CD where it condenses in the liquid phase under high pressure.

Le fluide frigorigène est ensuite détendu dans le détendeur D sous l'action du clapet 16 pour donner un mélange en phase liquide et en phase vapeur sous basse pression. Celui-ci est ensuite envoyé à l'évaporateur et en ressort à l'état de phase vapeur sous basse pression. Le fluide en phase vapeur traverse alors le second conduit entre les extrémités 58 et 60 en agissant sur le capteur thermostatique 56, avant de regagner le compresseur CP.The refrigerant is then expanded in the regulator D under the action of the valve 16 to give a mixture in liquid phase and in vapor phase under low pressure. This is then sent to the evaporator and leaves it in the vapor phase under low pressure. The vapor phase fluid then passes through the second conduit between the ends 58 and 60 by acting on the thermostatic sensor 56, before returning to the compressor CP.

Le condenseur CD est traversé par un flux d'air qui est échauffé à son contact, tandis que l'évaporateur E est traversé par un flux d'air qui est refroidi à son contact et qui est destiné à servir, dans l'exemple, à la climatisation d'un véhicule automobile.The condenser CD is crossed by an air flow which is heated on contact with it, while the evaporator E is crossed by an air flow which is cooled on contact with it and which is intended to serve, in the example, the air conditioning of a motor vehicle.

Le détendeur D crée une chute de pression dans le fluide frigorigène en phase liquide qui traverse le corps 10 entre l'entrée 12 et la sortie 14. Comme le liquide est incompressible, le détendeur D maintient la "surchauffe" qui assure l'état gazeux du fluide frigorigène à l'entrée du compresseur CP.The regulator D creates a pressure drop in the liquid phase refrigerant which passes through the body 10 between the inlet 12 and the outlet 14. As the liquid is incompressible, the regulator D maintains the "overheating" which ensures the gaseous state refrigerant at the inlet of the CP compressor.

En outre, le détendeur D contrôle le débit du fluide frigorigène en fonction de la charge calorifique absorbée par l'évaporateur E, laquelle varie suivant les différentes conditions de fonctionnement. Ainsi, seule la quantité nécessaire de fluide frigorigène est injectée pour une utilisation maximale de la surface d'échange.In addition, the expansion valve D controls the flow rate of the refrigerant as a function of the heat load absorbed by the evaporator E, which varies according to the different operating conditions. Thus, only the necessary quantity of refrigerant is injected for maximum use of the exchange surface.

Le fonctionnement du détendeur D est déterminé par l'équilibre de trois pressions :

  • la pression P1 du capteur thermostatique 56 dépendant de la température du fluide réfrigérant évaporé, et donc de la nature de la charge que contient le capteur thermostatique. Cette pression agit dans le sens de l'ouverture du clapet 16.
  • La pression P2 de l'évaporateur E qui, dans l'exemple, est prise en sortie de l'évaporateur. Cette pression agit dans le sens de la fermeture du clapet 16.
  • La pression P3 du ressort 32, dont la valeur est fixée pour le réglage de la surchauffe. Cette pression agit dans le sens de la fermeture.
The operation of the regulator D is determined by the balance of three pressures:
  • the pressure P1 of the thermostatic sensor 56 depending on the temperature of the evaporated refrigerant, and therefore on the nature of the charge contained in the thermostatic sensor. This pressure acts in the direction of opening of the valve 16.
  • The pressure P2 of the evaporator E which, in the example, is taken at the outlet of the evaporator. This pressure acts in the direction of closing the valve 16.
  • The pressure P3 of the spring 32, the value of which is fixed for adjusting the overheating. This pressure acts in the closing direction.

Tant que les trois pressions s'équilibrent, le passage du fluide frigorigène au travers du premier conduit reste ouvert.As long as the three pressures balance, the passage of the refrigerant through the first duct remains open.

Si l'évaporateur E n'est pas assez alimenté en fluide frigorigène, la température au niveau du capteur thermostatique 56 (bulbe) augmente, la pression P1 monte et entraîne une augmentation d'ouverture. Il en est de même pour une baisse de pression P2 dans l'évaporateur. Par contre, une baisse de température au niveau du capteur thermostatique 56 et une hausse de pression dans l'évaporateur E agissent dans le sens de la fermeture.If the evaporator E is not supplied with sufficient refrigerant, the temperature at the thermostatic sensor 56 (bulb) increases, the pressure P1 rises and causes an increase in opening. The same is true for a pressure drop P2 in the evaporator. On the other hand, a drop in temperature at the thermostatic sensor 56 and a rise in pressure in the evaporator E act in the closing direction.

Dans un tel dispositif, une condensation a tendance à se former, par échange de température, à l'extérieur du capuchon 78. Comme ce capuchon est ici maintenu par des points de sertissage formés directement dans le matériau du corps 10, dans l'exemple de l'aluminium, celui-ci ne risque pas de se corroder et de laisser échapper le capuchon et de conduire à une défaillance du détecteur.In such a device, condensation tends to form, by temperature exchange, outside the cap 78. As this cap is here held by crimping points formed directly in the material of the body 10, in the example aluminum, it will not corrode and allow the cap to escape and lead to a detector failure.

Le détecteur thermostatique de l'invention est destiné à être utilisé principalement dans les installations de climatisation de véhicules automobiles.The thermostatic detector of the invention is intended to be used mainly in air conditioning installations of motor vehicles.

Claims (7)

Détendeur thermostatique pour circuit de climatisation, comprenant un corps métallique (10) traversé par un premier conduit (12, 14) contrôlé par un clapet réglable (16) et par un second conduit (58, 60) logeant un capteur thermostatique (56) pilotant le clapet (16), et dans lequel le capteur thermostatique (56) est maintenu par un capuchon (78) logé dans un alésage (22) du corps (10),
caractérisé en ce que le capuchon (78) est maintenu en position par des points de sertissage (84) formés dans le corps (10) à la périphérie de l'alésage (22) et prenant appui sur le pourtour du capuchon (78).Thermostatic expansion valve for air conditioning circuit, comprising a metal body (10) through which a first duct (12, 14) controlled by an adjustable valve (16) and by a second duct (58, 60) housing a thermostatic sensor (56) driving the valve (16), and in which the thermostatic sensor (56) is held by a cap (78) housed in a bore (22) of the body (10),
characterized in that the cap (78) is held in position by crimping points (84) formed in the body (10) at the periphery of the bore (22) and bearing on the periphery of the cap (78). Détendeur thermostatique selon la revendication 1, caractérisé en ce que les points de sertissage (84) sont régulièrement espacés à la périphérie de l' alésage (22).Thermostatic expansion valve according to claim 1, characterized in that the crimp points (84) are regularly spaced around the periphery of the bore (22). Détendeur thermostatique selon l'une des revendications 1 et 2, caractérisé en ce qu'il comprend quatre points de sertissage (84) disposés à 90° les uns des autres par rapport au centre de l'alésage (22).Thermostatic expansion valve according to one of claims 1 and 2, characterized in that it comprises four crimping points (84) arranged at 90 ° from each other relative to the center of the bore (22). Détendeur thermostatique selon l'une des revendications 1 à 3, caractérisé en ce que les points de sertissage (84) sont obtenus par matage ou martelage.Thermostatic expansion valve according to one of claims 1 to 3, characterized in that the crimping points (84) are obtained by hammering or hammering. Détendeur thermostatique selon l'une des revendications 1 à 4, caractérisé en ce que le corps (10) est en aluminium ou alliage à base d'aluminium.Thermostatic expansion valve according to one of claims 1 to 4, characterized in that the body (10) is made of aluminum or an aluminum-based alloy. Détendeur thermostatique selon l'une des revendications 1 à 5, caractérisé en ce que le capuchon (78) est réalisé dans un matériau métallique choisi parmi l'aluminium, un alliage d'aluminium, le cuivre et un alliage de cuivre.Thermostatic expansion valve according to one of claims 1 to 5, characterized in that the cap (78) is made of a metallic material chosen from aluminum, an aluminum alloy, copper and a copper alloy. Détendeur thermostatique selon l'une des revendications 1 à 6, caractérisé en ce qu'un joint torique d'étanchéité (80) est interposé entre le capuchon (78) et l'alésage (22).Thermostatic expansion valve according to one of claims 1 to 6, characterized in that an O-ring seal (80) is interposed between the cap (78) and the bore (22).
EP96120353A 1995-12-27 1996-12-18 Thermostatic expansion valve for air conditioning circuit, especially of motor vehicle Withdrawn EP0781970A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR9515577A FR2743138B1 (en) 1995-12-27 1995-12-27 THERMOSTATIC REGULATOR FOR AIR CONDITIONING CIRCUIT, PARTICULARLY A MOTOR VEHICLE
FR9515577 1995-12-27

Publications (1)

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EP0781970A1 true EP0781970A1 (en) 1997-07-02

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EP (1) EP0781970A1 (en)
JP (1) JPH09296971A (en)
FR (1) FR2743138B1 (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19719251A1 (en) * 1997-05-07 1998-11-12 Valeo Klimatech Gmbh & Co Kg Distribution / collection box of an at least double-flow evaporator of a motor vehicle air conditioning system
DE19926570A1 (en) * 1999-06-11 2000-12-14 Behr Gmbh & Co Expansion valve for motor vehicle air conditioning system has valve rod with 2 sub-rods connected by element of expansion material, heated by electrically controlled heater
EP1128138A2 (en) * 2000-02-22 2001-08-29 TGK Co., Ltd. Expansion valve
EP1195546A1 (en) * 2000-10-03 2002-04-10 Kabushiki Kaisha Kobe Seiko Sho Valve device
EP1416236A1 (en) * 2002-10-29 2004-05-06 Fujikoki Corporation Expansion valve

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2327542A (en) * 1941-06-02 1943-08-24 Gen Controls Co Refrigerant control valve
US2551489A (en) * 1945-08-30 1951-05-01 George B Scarlett Diaphragm chamber
US2755025A (en) * 1952-04-18 1956-07-17 Gen Motors Corp Refrigeration expansion valve apparatus
US3139903A (en) * 1961-02-21 1964-07-07 Itt Expansion valve with adjustable metering orifice
US3388864A (en) * 1966-09-23 1968-06-18 Thomas E. Noakes Cartridge type expansion valve
US4819443A (en) * 1987-06-30 1989-04-11 Fujikoki America, Inc. Expansion valve
EP0438625A2 (en) * 1990-01-26 1991-07-31 TGK CO., Ltd. Expansion valve
DE4131385A1 (en) * 1991-09-20 1993-04-01 Bayerische Motoren Werke Ag Retention of washer in hole in workpiece - by means tool which deforms metal of wall of hole

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2327542A (en) * 1941-06-02 1943-08-24 Gen Controls Co Refrigerant control valve
US2551489A (en) * 1945-08-30 1951-05-01 George B Scarlett Diaphragm chamber
US2755025A (en) * 1952-04-18 1956-07-17 Gen Motors Corp Refrigeration expansion valve apparatus
US3139903A (en) * 1961-02-21 1964-07-07 Itt Expansion valve with adjustable metering orifice
US3388864A (en) * 1966-09-23 1968-06-18 Thomas E. Noakes Cartridge type expansion valve
US4819443A (en) * 1987-06-30 1989-04-11 Fujikoki America, Inc. Expansion valve
EP0438625A2 (en) * 1990-01-26 1991-07-31 TGK CO., Ltd. Expansion valve
DE4131385A1 (en) * 1991-09-20 1993-04-01 Bayerische Motoren Werke Ag Retention of washer in hole in workpiece - by means tool which deforms metal of wall of hole

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
"METAL STAKING", PRODUCT ENGINEERING, 4 September 1961 (1961-09-04), pages 354 - 358, XP002012816 *
H. EDER: "FEINWERKTECHNISCHE VERBINDUNGEN DURCH PLASTISCHES VERFORMEN", FEINWERKTECHNIK, vol. 65, no. 4, April 1961 (1961-04-01), pages 135 - 152, XP000617738 *

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19719251A1 (en) * 1997-05-07 1998-11-12 Valeo Klimatech Gmbh & Co Kg Distribution / collection box of an at least double-flow evaporator of a motor vehicle air conditioning system
DE19719251C2 (en) * 1997-05-07 2002-09-26 Valeo Klimatech Gmbh & Co Kg Distribution / collection box of an at least double-flow evaporator of a motor vehicle air conditioning system
DE19926570A1 (en) * 1999-06-11 2000-12-14 Behr Gmbh & Co Expansion valve for motor vehicle air conditioning system has valve rod with 2 sub-rods connected by element of expansion material, heated by electrically controlled heater
EP1128138A2 (en) * 2000-02-22 2001-08-29 TGK Co., Ltd. Expansion valve
EP1128138A3 (en) * 2000-02-22 2002-01-02 TGK Co., Ltd. Expansion valve
EP1195546A1 (en) * 2000-10-03 2002-04-10 Kabushiki Kaisha Kobe Seiko Sho Valve device
US6533245B2 (en) 2000-10-03 2003-03-18 Kabushiki Kaisha Kobe Seiko Sho Valve device
EP1416236A1 (en) * 2002-10-29 2004-05-06 Fujikoki Corporation Expansion valve
US6896190B2 (en) 2002-10-29 2005-05-24 Fujikoki Corporation Expansion valve
CN100422666C (en) * 2002-10-29 2008-10-01 株式会社不二工机 Expansion valve

Also Published As

Publication number Publication date
JPH09296971A (en) 1997-11-18
FR2743138B1 (en) 1998-02-13
FR2743138A1 (en) 1997-07-04

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