FR2640315A1 - INTERNAL COMBUSTION COOLING DEVICE - Google Patents

Abstract

The present invention relates to a liquid cooling device for an internal combustion engine which comprises a main cooling circuit comprising a radiator 4 connected to the engine 1 and a thermostatic valve 6 capable of interrupting the circulation of the liquid when the temperature of this is less than a given value, at least one secondary cooling circuit mounted in parallel with the main circuit and comprising a degassing chamber 14 of small volume connected to the engine 1 by a liquid inlet pipe 17 and a pipe starting point 18, and means 2 for circulating the liquid between the engine 1 and the degassing chamber 14, and an expansion tank 8 connected to one of the cooling circuits. According to the invention, the expansion vessel 8 is connected to the main cooling circuit and one of the walls of the degassing chamber 14 has an orifice 20 connected to the expansion vessel 8 by means of a valve 21 or 26 arranged to open when gas is present in chamber 14.

Description

The cooling circuit of an internal combustion engine shall

  necessarily include a device for degassing because it can not ensure an absolute seal

  between the inside of the cylinders and the water chambers.

  The engine itself can be degassed. But we increase

  then significantly the volume of heating fluid

  as soon as the engine is started, as this involves heating the liquid contained in the expansion tank as soon as it is switched on; we are delaying the rise

  temperature of this engine and its cooling circuit

  This increases the external pollution caused by

  prolonged use of enrichment systems

  consequently, also increases the fuel consumption and, in the case of a vehicle engine, harms the heating of the passenger compartment

of the vehicle.

  It is also possible to degas the radiator. But always

  in order to arrive quickly at normal temperatures

  When the engine is running, the coolant is not circulated in the radiator as soon as the engine is started. For example, it is possible to use a thermostatic valve which prevents the circulation of the

  when the temperature of the latter is below

  than a given value. This circulation does not

  therefore, that after the start-up period and the

  zage intervenes only at this time, which is a disadvantage. French Patent 2,317,489 discloses a liquid cooling device of a combustion engine

  internal circuit which ensures a degassing of the cooling circuit

  at the start of the market while minimizing

  setting the coolant volume to heating

  iron after this start. This system of

  cooling has a main cooling circuit

  a radiator connected to the engine by

  a liquid inlet duct and a return duct

  turn, ways to circulate the liquid between

  the engine and the radiator, and a thermostatic valve

  that is suitable for interrupting the circulation of the liquid - 3 - when the temperature of the latter is less than

  a given value, a secondary cooling circuit

  discharge connected in parallel with the main circuit and comprising a low volume degassing chamber connected to the motor by a liquid inlet duct

  and a starting line, and means for cir-

  the liquid between the engine and the

  gassing, and an expansion vessel connected to one of the

baked cooling.

  The present invention relates to an improvement

  brought to this cooling device. According to the

  vention, the cooling device is characterized

  in that the expansion vessel is connected to the cir-

  cooked main cooling and in that one

  walls of the degassing chamber comprises a

  fice connected to the expansion vessel via a valve arranged to open when gas is present in the chamber; when the valve opens, the gas from the degassing chamber thus escapes to

the expansion tank.

  In an advantageous embodiment of the invention, the degassing chamber is disposed under the vessel

  the orifice and allows for a di-

  between the upper part of the chamber of de-

  gassing and the lower part of the expansion vessel.

- 4 -

  We have described hereinafter, by way of nonlimiting example,

  various embodiments of the device according to the

  tion, with reference to the accompanying drawings in the-

  which: Figure 1 is the diagram of this cooling device; Figure 2 is a sectional view of the degassing chamber along II-II of Figure 1; Figure 3 shows another embodiment of the valve;

  Figure 4 shows a third mode of

flap valve;

  Figure 5 shows a fourth mode of

  flap valve; Figure 6 is a schematic view illustrating

  an achievement in which the chamber of

  zage is removed from the expansion vessel and connected to

this one by a conduit.

  In Figure 1, there is shown an internal combustion engine 1 which has a main cooling circuit

comprising a pump 2.

  The liquid flows through the motor and comes out of it

  ci by several circuits, namely: - - A main circuit which comprises a radiator 4 connected to the engine 1 by an inlet duct 5 and a return duct 3. This circuit comprises a valve or a thermostatic valve 6 which is closed when the coolant temperature is below a given value. The return duct 3 is connected, via a duct 7, to the lower part of an expansion tank 8. The latter is closed at its upper part by a calibrated plug 9

  and it is connected to a degassing device 10 of the

diateur 4.

  - Two secondary circuits in which the liquid circulates continuously:

  (a) a circuit used for heating the dwelling

  including a heat exchanger 11

  linked to the motor by a supply duct 13 and a return duct 12;

  (b) a pipe for heating the organs

  nexes 16 such as starter, idle circuit, etc ...

  as well as degassing of the engine. It consists of ducts 15,17,18 and a degassing chamber

  14. The liquid leaving the engine passes successively

  in the duct 15, the organ or members 16,

  the conduit 17, the chamber 14 and returns to the

  drawing of the pump 2 through the conduit 18.

264O315

- 6 -

  As seen in Figure 2, the degassing chamber 14 has a circular section and the ducts 17 and 18 are of small section, lower than that of the ducts

  3 and 5, and open tangentially.

  The degassing chamber 14 is placed under the vase

  8 and attached to it by its upper part.

  the upper wall of the chamber constituting

  a part of the lower wall 19 of the vase; she

  door has a small section 20 through which it can communicate directly with the expansion tank and which can be closed by a valve 21. The apparent density of the valve is slightly less than or equal to the density of the coolant. It is connected at its upper part by an arm 22 to retaining arms 23 which limit its stroke downwards.

  by coming up against the partition 19.

  However, we would not go beyond the scope of the invention

  using the configuration of Figure 6 in the-

  the chamber 14 is remote from the expansion vessel 8.

  In this case, the arms 23 of the valve 21 are in

  a chamber 28 communicating with the degassing chamber

  ge 14 through the orifice 20, the chamber 28 being in communication

  nication with the expansion vessel 8 via a conduit 29.

  This makes it possible to mount the device of the invention on

  a cooling system for a vehicle already in existence

  7 - so much. When the cold engine starts, the valve 6 is closed,

  so that there is no circulation in the radia-

  4. The only liquid that passes through the expansion vessel 8 is the one that passes through the orifice 20. Given that

  the small dimensions of this orifice and the weak

  pipe 17, the pressure P in the vase of ex-

  pansion 8 is virtually identical to the pressure of

  piration. On the other hand, the pressure P 'in the chamber 14 is intermediate between the pressure in the engine before the valve 6, itself close to the delivery pressure of the pump 2, and the suction pressure of this pump. The pressure P 'in the chamber 14 is

  therefore greater than the pressure P in the vase of expan-

  if we. Under the effect of the pressure difference (P '- P)

  and the buoyancy of Archimedes due to its light density-

  less than that of the liquid, the valve 21 comes to rest on its seat practically as soon as

engine running.

  When gas has accumulated in the chamber 14, it is concentrated in the area where the valve 21 is located because of the rotation of the liquid in this chamber. The

  Archimedes' thrust on valve 21 decreases and

  as soon as the following inequality is verified: p> (pl - p) s -8 -

  p being the weight of the float less the thrust of Ar-

  chimed and s the section of the orifice 20.

  If this inequality is not verified in a certain embodiment, we can increase the volume of the valve, so its weight, decrease the section s or the difference

  P '- P, this reduction can be obtained by modifying

  relying on the internal dimensions of the ducts 15, 17 and 18,

  by increasing the head losses upstream of the chamber

  14, for example by providing a diaphragm on one

  ducts 15 and 17, or by decreasing the loss of

  In Figures 1 and 2, the valve 21 is constituted by a spherical body, which can be retained by the arms 23 which it is integral and the orifice 20 is formed in a flat portion of the partition 19. But in the embodiment of Figure 3, the orifice 20 is formed in a spherical portion 19a of the partition 19 and the valve 21 is retained by arms 24 integral with the

  partition. A stilling grid 25 may be

  to be provided under the flapper.

  In the embodiment of Figure 4, the valve is constituted by a cylindrical mass 26 which carries at its upper part a finger 27 clean to close

  the orifice 20 which is formed in a truncated portion

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  or spherical 19b of the partition 19. The mass 26 is guided and retained by the arms 24 secured to the partition 19. The stilling grid 25 hooked

  24 is also provided in this embodiment.

  tion. Figure 5 illustrates an embodiment similar to that of Figure 4. As previously, the valve 30

  is mobile in a limited space by a truncated part

  19 It is composed of a body 31 extended by an upper portion 32 and a lower portion 33 of smaller dimensions. The portion 32 carries the finger 27 and is guided by centering arms 34. The lower portion 33 is cross-shaped and passes through an orifice 35.

  of the grid 25. The lower face of the body 31 presents

  a part 36 in the form of a truncated cone to avoid

  an accidental collage on the grid 25.

  It goes without saying that the present invention should not be

  considered limited to the various modes of

  described and represented, but covers, on the contrary,

re, all variants.

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Claims (12)

claims   1. Liquid cooling device of a type   internal combustion engine which includes a main circuit   cooling member comprising a radiator (4)   linked to the engine (1) via an inlet duct (5) of the   quide and a return duct (3), means (2) for   circulate the liquid between the engine (1) and the   diator (4), and a thermostatic valve (6) suitable for   interrupt the circulation of the liquid when the temperature   of the latter is less than a given value, at least one secondary cooling circuit connected in parallel with the main circuit and comprising a low volume degassing chamber (14) connected to the motor (1) by an inlet duct (17) liquid and a flow line (18), and means (2) for circulating the liquid between the motor (1) and the degassing chamber (14), and an expansion vessel (8) connected to one of the cooling circuits, characterized in that the expansion tank (8) is connected to the main cooling circuit and in that one (19) of the walls of the degassing chamber (14) has a orifice (20) connected to the expansion vessel (8) via a valve (21 or 26) arranged to   open when gas is present in the chamber (14). - he -   2. Cooling device according to the claim   1, characterized in that the degassing chamber (14) is arranged under the expansion vessel (8) and in that the orifice (20) allows direct communication between the upper part of the degassing chamber (14). )   and the lower part of the expansion vessel (8).   3. Cooling device according to the claim   1, characterized in that the degassing chamber (14) is remote from the expansion vessel (8), said orifice (20)   being connected thereto by a conduit (29).   4. Cooling device according to one of the   1 to 3, characterized in that the degassing chamber (14) is   of circular section and that the ducts of   trea (17) and exit (18) are tangentially   is lying. 5. Cooling device according to any one Claims 1 to 4,   characterized in that the valve (21, 26 or 30) has a   density at most equal to that of the coolant   ment. 6. Cooling device according to any one of the preceding claims, - 12 -   characterized in that the conduits (17 and 18) connecting   the degassing chamber (14) to the engine (1) have a   less than the connecting ducts (3 and 5) the radiator (4) to this engine (1).   7. Cooling device according to any one   than the preceding claims,   characterized in that the valve (21) comprises at its   upper part of the retaining arms (23) which   try to race down against the partition (19) of the chamber (14).   8. Cooling device according to any one Claims 1 to 6,   characterized by retaining arms (24) integral with the wall (19) and limiting the travel of the valve (21) down.   9. Cooling device according to any one of the preceding claims,   characterized in that the valve (21) is spherical.   10. Cooling device according to one of the   preceding claims, characterized in that the orifice (20) is provided in a flat part of the wall (19).   11. Cooling device according to any one that claims 1 to 9,   Characterized in that the orifice (20) is formed in   a spherical portion (19a) of the wall (19).   12. Cooling device according to any one that claims 1 to 8,   characterized in that the valve (26) is constituted by a cylindrical mass which carries at its upper part a clean finger to close the orifice (20) formed in   a frustoconical portion (19b) of the partition (19).