KR20060046371A - Cooled valve seat ring - Google Patents

Abstract

The present invention provides a cooling valve for a cylinder head of an internal combustion engine having a valve controlled inlet and an exhaust port, having a hollow space through which a cooling medium flows and which can be connected to a cooling medium circulation circuit of an internal combustion engine via an appropriate passage. Relates to a seat ring. Such a valve seat ring exhibits excellent cooling properties and can be manufactured simply technically, and the valve seat ring is fixedly assembled and joined to the annular flow channel 6 so that its receiving area in the cylinder head is protected from corrosion. Two or more ring parts (4, 5; 21, 22) enclosing the annular flow channel (6) after the valve seat ring is pressed into the cylinder head (1) forming an interference fit surface. Measures are taken to allow integration into the cooling medium circulation circuit of the internal combustion engine via inlet and outlet holes 10 in the ring component.

Description

Cooled Valve Seat Ring {COOLED VALVE SEAT RING}

1 is a schematic partial cross-sectional view of a cylinder head of a water-cooled internal combustion engine having an intake port or an exhaust port, in which a first embodiment of a valve seat ring according to the invention is disposed;

2 is a schematic partial cross-sectional view as in FIG. 1 according to a second embodiment of a valve seat ring according to the invention;

<Explanation of symbols for the main parts of the drawings>

1: cylinder head

3, 20: valve seat ring

4, 5, 21, 22: ring parts

6, 23: annular flow channel

10, 24: inlet and outlet holes

25: fixed part

26: valve seat

27: middle section

29: round sealing ring

The present invention provides a cooling valve for use in a cylinder head of an internal combustion engine having a valve controlled inlet and an exhaust port, having a hollow space through which a cooling medium flows, and connected to a cooling medium circulation circuit of an internal combustion engine via an appropriate passage. Relates to a seat ring.

In particular, it is known to cool the valve seat of the exhaust valve of an internal combustion engine, especially the valve seat ring subjected to a high thermal load. In the region of the exhaust valves of internal combustion engines, attempts to achieve good heat dissipation by bringing the coolant jacket as close to the valve seat ring as possible. In a practical multi-valve cylinder head of an internal combustion engine with a diesel direct injection device and a centrally positioned injection nozzle, the tight water situation makes the coolant jacket unable to play a satisfactory role.

Cooled valve seat rings of the type mentioned for example at the outset are known from DE 43 28 904 C2.

Typically, cooling of the valve seat ring is done by a cooling channel between the valve seat ring and the cylinder head and with cooling water flowing through it at a sufficiently high speed. In order to reach the coolant as close as possible to the valve seat, ie the contact surface between the valve seat ring and the lifting valve, it is necessary to remove and remove the fixing part of the valve seat ring. Since that requires a free passageway for the machining tool, the flow cross section of the cooling channel will be larger than necessary to achieve the desired flow rate. Thereby, a filling ring is provided in the center region of the valve seat ring to reduce the flow transverse cross section of the processed cooling channel. However, such technically complex configurations place stringent requirements that are undesirable for manufacturers.

In addition, various measures are known for improving the heat release from the valve, in particular here, the heat release from the valve seat. Also included is a cooled valve seat of the type mentioned at the outset, which encloses the approximately annular cooling space with the part of the cylinder head surrounding it, in which the cooling medium is operated in the operation of the internal combustion engine with the valve. Will flow through. Known cooled valve seats of that type have a valve seat ring, such as a valve seat ring of the type mentioned at the outset, which is press-fitted into the inlet of each channel, which valve seat ring is more particularly after a long operating time of the internal combustion engine. It may become looser and thus result in loss of sealability and hence leakage of coolant into the cylinder of the internal combustion engine, for example.

In order to eliminate or avoid the problem of such a loss of sealability of the pressurized valve seat ring, it is known to use an O-ring-shaped packing of a special heat-resistant material, for example, to be fitted when the valve seat ring is pressed into the recess. . It complicates the manufacture and assembly of the valve seat on the one hand and on the other hand still leads to a loss of sealing in the cooling system of the valve seat ring due to the relatively high thermal load on the packing ring too. .

For that reason, cooling in such areas becomes inefficient.

The object of the present invention, including an internal combustion engine with a cooled valve seat ring of the type mentioned at the outset, shows good cooling characteristics, can be produced simply technically, and its receiving area in the cylinder head is protected from corrosion. To provide a valve seat ring of that type.

Such an objective is technically made up of two or more ring parts, in which the valve seat ring is fixedly assembled and enclosed in an annular flow channel, and the annular flow channel is formed after the valve seat ring is pressed into the cylinder head forming an interference fit face. This is accomplished by measures that allow integration into the cooling medium circulation circuit of the internal combustion engine via inlet and outlet holes in one or more ring parts.

The water-cooled internal combustion engine formed according to such a technical idea has the advantage that the valve seat ring is optimally cooled.

By integrating the cooling channel into the valve seat ring, the receiving area of the cylinder head is effectively protected from corrosion.

Another advantage is that the valve seat ring can be manufactured technically simply by a simple machining and solder joint method.

In order to assemble and bond the above-mentioned parts, various kinds of tungsten-inert gas welding (WIG), metal-inert gas welding (MIG), metal-active gas welding (MAG), or beam welding by laser or electrode beams can be used. Welding methods can be considered. However, such a joining method is complicated and expensive. In addition, a welded joint cannot be made without indentation.

Therefore, it is preferable to form the joining joint of components by a solder joint method. Such measures enable, on the one hand, the joining of parts of the same or different materials, and on the other hand provide a high strength of the joining. In addition, thereby, a joining seam without nicking is obtained.

In particular, high temperature soldering provides bonds with very high heat resistance. Hot soldering is a method of bonding and coating with solder in a vacuum or protective gas whose liquidus temperature is above 900 ° C. In that case, the mainly used solders are nickel-based solders, gold / nickel-based solders, and other precious metal solders and copper and copper-based solders.

The material selection of the part depends on the thermal load. The thermal expansion of the bonding partner should be approximately equal.

In particular, the joining by high temperature vacuum soldering makes it possible to produce an integral valve seat ring incorporating a cooling channel directly by its excellent reproducibility. Such high temperature vacuum soldering enables an indentation-free coupling as compared to the above-described weld bonding, and can bond various materials to each other.

Hereinafter, the present invention will be described in more detail based on two examples.

According to FIG. 1, in the cylinder head 1 of a water-cooled internal combustion engine (not shown), intake and exhaust valves are usually arranged for each cylinder and inserted into corresponding intake and exhaust channels 2 in the cylinder head 1.

At the inlet of such a channel 2 is inserted a valve seat ring 3 which can seal the channel 2 with respect to the cylinder space together with the valve head. Such a valve seat ring 3 consists of two ring parts 4, 5, namely a seat ring upper part and a seat ring lower part, in which the cooling annular space 6 is integrated in the assembled and bonded state. Form an integral valve seat ring. In that case, the valve seat ring 3 is inserted or pressed into the annular recess 7 of the intake or exhaust channel 2 of the cylinder head 1. The cooling annular space 6 has a flow communication path 10 through the inlet or outlet opening 8 of the cooling medium, where the side forming the interference fit face 9 defines the inlet or outlet hole 10. Equipped.

That is, the ring parts 4 and 5 fixedly assembled and joined are formed by a cylindrical interference fitting face 9 toward the cylinder head 1, and are connected to the valve-controlled intake and exhaust openings 2 of the cylinder head 1. It is in close contact with the flat surface 11 of the recess 7.

As the outer diameter of the valve seat ring is not cylindrical, a permanent interference fit is realized. Thereby, a markedly improved heat dissipation via the cylinder head 1 is obtained. That is, the temperature in the valve seat 3a is further lowered. Sealing by the circular sealing ring can be omitted.

The integrated cooling channel 6 can be formed variably, thereby allowing a small gap to the valve seat 3a as desired.

By closing the annular cooling channel integrated into the valve seat ring 3, the receiving zone in the cylinder head 1 is protected from corrosion and good heat transfer is provided by the relatively large interference fit face 9.

Figure 2 shows another embodiment of a valve seat ring according to the invention. Parts corresponding to those in FIG. 1 are given the same reference numerals.

The first ring part 21 of the valve seat ring 20 is formed with an annular cooling channel 23 which is open towards the cylinder head 1. The relatively thin walled sleeve-like second ring part 22 which concentrically surrounds the first ring part 21 has a first ring part 21 such that the annular cooling channel 23 is closed towards the cylinder head 1. Is fixedly assembled to and joined to, in which case an inlet or outlet hole 24 is provided in the sleeved ring part 22 which connects the cooling channel 23 to the cooling medium circulation circuit 8.

The seat ring of the first ring component, ie the valve seat ring 20, is provided with a fixing portion 25, a valve seat 26 for receiving the valve, and an intermediate section 27, which are sleeve-like second ring components 22. ) Seals the intermediate zone, ie the cooling channel 23 against the cylinder head 1, and makes an interference fit to the cylinder head 1.

The cooling channel 23 is made by removing the fixing part 25, and the sleeve-shaped second ring part 22 is at least partially removed from the fixing head 25 by the leg 28. Shield against.

The intermediate zone 27 is formed with a short outer diameter in contrast to the fixing part 25. Due to such a short outer diameter, it is necessary to seal between the cylinder head 1 and the valve seat ring 20 by the circular sealing ring 29. Therefore, a circular sealing ring 29 is provided between the cylinder head 1 and the second ring component 22. In this embodiment also the casting material of the cylinder head 1 is protected from corrosion by the sleeved ring part 22 as a shield of the cooling channel 23. The circular sealing ring 29 is sandwiched between the sleeve 22 and the cylinder head, preferably in the cold material of the cylinder head 1, so that it additionally cools from the inside via the thin-walled sleeve 22. Will be. Thus, the endurance life of the circular sealing ring 29 can be significantly long.

The present invention consists of two or more ring components in which the valve seat ring is fixedly assembled to surround the annular flow channel, and the annular flow channel is one or more rings after the valve seat ring is pressed into the cylinder head while forming an interference fit surface. By allowing the components to be integrated into the cooling medium circulation circuit of the internal combustion engine via the inlet and outlet holes in the parts, the valve seat ring is optimally cooled, and the cooling channel is integrated into the valve seat ring and closed to accommodate the cylinder head. The zone will be effectively protected from corrosion. Another advantage is that the valve seat ring can be manufactured technically simply by a simple machining and solder joint method.

Claims (9)

A cooled valve seat ring for a cylinder head of an internal combustion engine having a valve controlled inlet and an exhaust port, having a hollow space through which a cooling medium flows and connected to a cooling medium circulation circuit of an internal combustion engine via an appropriate passage. The valve seat rings 3, 20 consist of two or more ring parts 4, 5; 21, 22 which are fixedly assembled and joined to surround the annular flow channels 6, 23, with the valve seat rings being tightly fitted. After being pressed into the cylinder head 1 while forming the face 9, the annular flow channels 6; 23 pass through the inlet and outlet holes 10, 24 in the one or more ring parts. Cooled valve seat ring, characterized in that it can be incorporated into. 2. The valve seat ring (3) according to claim 1, wherein the valve seat ring (3) occupies approximately half spaces (6a, 6b), respectively, and forms an integral valve seat ring in which the cooling channel (6) is integrated in the assembled state, and the interference fit face Cooling valve seat ring, characterized in that it consists of two ring parts (4, 5) having inlet or outlet holes (10) on its side to form a. 2. The ring-shaped cooling channel (23) according to claim 1, wherein an annular cooling channel (23) is formed in the first ring part (21), which opens towards the cylinder head (1), and has a relatively thin wall that concentrically surrounds the first ring part (21). The sleeved second ring part 22 is fixedly assembled and joined to the first ring part 21 so that the annular cooling channel 23 is closed toward the cylinder head 1, and the cooling channel 23 is connected to the cooling medium circulation circuit. A cooled valve seat ring characterized in that an inlet or outlet hole (24) for connecting to (8) is provided in the sleeve-like ring part (22). 4. The first ring component (21) according to claim 3, wherein the first ring component (21) is provided with a fixing portion (25), a valve seat (26) for receiving the valve, and an intermediate section (27). A cooled valve seat ring, characterized in that an intermediate zone (27) with cooling channels (23) is sealed against the cylinder head (1) and an interference fit to the cylinder head (1) is achieved. The cooling channel (23) according to claim 3 or 4, wherein the cooling channel (23) is made by removing the fixing part (25) and the sleeved second ring part (22) is fixed by the leg part (28). Cooling valve seat ring at least partially shielding the cylinder head (1). 6. The intermediate zone (27) according to claim 4 or 5 has a short outer diameter as opposed to the fixing part (25), and a circular sealing ring (c) between the cylinder head (1) and the sleeve-shaped second ring part (22). 29) provided with a cooled valve seat ring. The ring component 4, 5 which is fixedly assembled and joined is provided with a cylindrical interference fitting face 9 towards the cylinder head 1, and the valve controlled intake of the cylinder head 1. And a close contact with the flat face (11) of the recess (7) in the exhaust opening (2). Cooling valve seat ring according to any of the preceding claims, characterized in that the ring parts (4, 5; 21, 22) are fixedly joined to each other by a solder joint method. Cooling valve seat ring according to claim 8, characterized in that the ring parts (4, 5; 21, 22) are fixedly joined to each other by hot vacuum soldering.

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