CN105240077A - Air valve with screw cavity charged with sodium and with screw blade - Google Patents

Abstract

The invention discloses an air valve with a screw cavity charged with sodium and with a screw blade. The screw blade extending in the axial direction of an air valve head is arranged on the outer side wall of the air valve head. A screw runner is arranged in an air valve rod and charged with sodium. A chromium coating is arranged on the surface of the air valve rod. A ring groove is formed in the circumferential direction of the air valve head. An overlaying layer is arranged in the ring groove in a covering manner, and the surface of the overlaying layer is a conical surface. According to the air valve with the screw cavity charged with sodium and with the screw blade, heat accumulated at an air valve neck and the center of the end face of the air valve head can be conducted away well, and therefore the air valve is uniform in heat dissipation.

Description

Helical chamber flush sodium valve with helical blades

technical field

The invention relates to the field of engine parts, in particular to a helical cavity flush sodium valve with helical blades.

Background technique

In the past, the gasoline engine exhaust valve was made of solid exhaust valve, the head of the exhaust valve was made of high temperature resistant austenite material, the rod was made of martensite material, and then processed by welding, surface treatment and other processes. Exhaust valves of this structure and process can only be used on naturally aspirated gasoline engines whose exhaust temperature does not exceed 750°C. In a supercharged engine, due to the use of compressed air intake technology (specifically turbocharging, supercharging and dual supercharging), the combustion explosion pressure in the cylinder is higher than that of natural suction, and the temperature in the cylinder is also higher than that of natural gas. When the intake is high, the temperature of the exhaust valve rises accordingly. Therefore, the temperature at the exhaust valve often exceeds the allowable temperature of the material of the exhaust valve, thereby reducing the service life of the exhaust valve and reducing the heat dissipation performance. In order to solve this problem, people drill a hole in the valve stem of the exhaust valve to form a cavity. The melting point of metal sodium is 97.81°C. Under the premise of a reasonable hollow cavity volume, when the valve is working, the temperature rises rapidly. Metal sodium changes from solid to liquid at high temperature, and moves up and down in the hollow cavity to continuously scour the valve face and valve stem, effectively transfer the heat load at the end of the valve face to the valve stem, and then cool the exhaust valve through the water passage in the cylinder head , which improves the heat dissipation of the exhaust valve and effectively reduces the heat load on the valve surface. In addition, the specific gravity of metal sodium is small, the overall mass of the valve becomes smaller, and the stiffness of the valve becomes stronger. Under the same conditions, the deformation of the valve is less Small; however, there is a problem with the existing hollow sodium-filled exhaust valve: the heat at the center of the valve neck and the end face of the valve head is not easy to be smoothly conducted away, and it is the place where the temperature gathers, which will affect the heat dissipation uniformity of the exhaust valve , reducing exhaust valve life.

Therefore, in order to solve the above problems, it is necessary to conduct the heat accumulated at the center of the valve neck and the end surface of the valve head, so that the valve head can dissipate heat evenly.

Contents of the invention

In view of this, the purpose of the present invention is to overcome the defects in the prior art, and to provide a helical valve that can better conduct away the heat accumulated at the center of the valve neck and the end surface of the valve head, so that the exhaust valve can dissipate heat evenly. The helical cavity of the blade flushes the sodium valve.

The spiral cavity flushing sodium valve with spiral blades of the present invention comprises a valve head and a valve stem. The outer wall of the valve head is provided with a spiral blade extending axially around it. There is sodium, the surface of the valve stem is provided with a chrome-plated layer, and the valve head is provided with a ring groove along its circumference. The ring groove is covered with a surfacing layer and the surface of the surfacing layer is a conical surface;

Further, the contact surface between the ring groove and the surfacing layer is an arc surface;

Further, the bottom surface of the valve head is provided with a circular groove coaxial with the valve head;

Further, the length of the valve guide that cooperates with the helical sodium valve with helical blades is S ₁ , the stroke of the helical sodium valve with helical blades relative to the valve guide is S ₂ , and the surface of the valve stem is chrome-plated The axial length of the layer is S ₁ +S ₂ ;

Further, a circular groove is provided on the cylindrical surface near the top end of the valve stem along the circumference, and the diameter of the bottom of the groove is smaller than the inner diameter of the valve lock clip.

The beneficial effect of the present invention is: the spiral chamber with the spiral blade of the present invention flushes the sodium valve, and the spiral blade on the valve head can be driven by the discharged air flow to wash the spiral blade to drive the valve to rotate, which can not only improve the circulation of the gas, but also increase the number of valves. The rigidity, and more importantly, reduce the carbon deposition of the valve and valve seat, so as to ensure the good sealing and long life of the valve. The spiral flow channel is conducive to guiding the spiral flow of metal sodium. Compared with the existing cylindrical flushing sodium As far as the valve of the cavity is concerned, the flow path of the spiral flow channel of the present invention is longer, which can enhance the heat exchange rate between the metal sodium in the cavity and the valve head; will be reduced, and the chrome-plated layer on the surface of the valve stem can make up for the mechanical strength of the valve stem, and at the same time improve its heat resistance; Effectively improve the wear of the valve head.

Description of drawings

The present invention will be further described below in conjunction with accompanying drawing and embodiment:

Fig. 1 is a structural representation of the present invention;

Fig. 2 is a partial enlarged view of place A in Fig. 1;

Fig. 3 is a structural schematic diagram of the spiral blade of the present invention.

detailed description

Fig. 1 is a schematic structural view of the present invention, and Fig. 2 is a partial enlarged view of A in Fig. 1, as shown in the figure, the helical chamber flush sodium valve with helical blades in this embodiment includes a valve head 3 and a valve stem 5 The outer wall of the valve head 3 is provided with a spiral blade 4 extending axially around it, the inside of the valve stem 5 is provided with a spiral flow channel 9, the spiral flow channel 9 is filled with sodium, and the surface of the valve stem 5 is provided with a chrome-plated layer 6, The valve head 3 is provided with an annular groove 8 along its circumference, and the inner groove 8 is covered with a surfacing layer 2 and the surface of the surfacing layer 2 is a conical surface; the spiral flow channel 9 in the valve stem 5 can guide the spiral flow of liquid metal sodium, compared with For the existing valve that uses a cylindrical cavity for sodium flushing, the spiral flow channel 9 of the structure of the present invention can extend the flow length of the flow channel and can enhance the heat exchange rate between the metal sodium in the cavity and the valve head 3 In addition, the surfacing layer 2 arranged in the circumferential direction of the valve head 3, which cooperates with the valve seat ring, can effectively improve the wear of the valve head 3, and the chrome-plated layer 6 on the surface of the valve stem 5 can improve the mechanical strength of the valve and heat resistance.

In this embodiment, the contact surface between the annular groove 8 and the overlay layer 2 is an arc surface 11, and the arc surface 11 can increase the contact area between the overlay layer 2 and the valve head 3, ensuring that the overlay layer 2 and the valve head Head 3 is firmly connected.

In this embodiment, the bottom surface of the valve head 3 is provided with a circular groove 1 coaxial with the valve head 3. This circular groove 1 is used as a part of the combustion chamber of the engine. By adjusting the size of the circular groove 1, the engine can be adjusted within a certain range. compression ratio.

In this embodiment, the length of the valve guide that cooperates with the helical sodium valve with helical blades is S ₁ , and the stroke of the helical sodium valve with helical blades moving relative to the valve guide is S ₂ , the valve The axial length of the chrome-plated layer on the surface of the rod 5 is S ₁ +S ₂ , as shown in Figure 1, the dot-dash line frame area is the chrome-plated layer 6, which is used to slide and cooperate with the valve guide to reduce wear and improve The utilization rate of the chrome-plated layer 6 saves cost. The axial length of the chrome-plated layer 6 used in this embodiment is the sum of the length of the valve guide and the valve stroke, so as to ensure that the contact surface of the valve stem 5 and the valve guide is even in the process of reciprocating motion. It is covered with a chrome layer 6, which enhances its wear resistance.

In this embodiment, the cylinder surface near the top of the valve stem 5 is provided with a lock clip groove 7 along the circumference, and the bottom diameter of the lock clip groove 7 is smaller than the inner diameter of the valve lock clip, so as to ensure the reliable connection between the valve stem 5 and the valve.

Finally, it is noted that the above embodiments are only used to illustrate the technical solutions of the present invention without limitation. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be carried out Modifications or equivalent replacements without departing from the spirit and scope of the technical solution of the present invention shall be covered by the claims of the present invention.

Claims (5)

1. a helical cavity with helical blade rushes sodium valve, comprise valve head and valve stem, it is characterized in that: described valve head outer side wall is provided with around its axially extended helical blade, and described valve stem inside is provided with spiral flow channel, in described helical flow path, punching has sodium; Described valve stem surface is provided with chromium coating; Described valve head is circumferentially with annular groove along it; Overlay cladding is coated with and overlay surface is conical surface in described annular groove.

2. the helical cavity with helical blade according to claim 1 rushes sodium valve, it is characterized in that: the surface of contact of described annular groove and overlay cladding is arc surface.

3. the helical cavity with helical blade according to claim 2 rushes sodium valve, it is characterized in that: described valve head bottom surface is provided with the circular groove coaxial with valve head.

4. the helical cavity with helical blade according to claim 3 rushes sodium valve, it is characterized in that: the length that the helical cavity having helical blade with this rushes the valve guide bushing that sodium valve coordinates is S ₁, it is S that this helical cavity with helical blade rushes sodium valve relative to the stroke that valve guide bushing moves ₂, the axial length of described valve stem plated surface layers of chrome is S ₁+ S ₂.

5. the helical cavity with helical blade according to claim 4 rushes sodium valve, it is characterized in that: described valve stem is circumferentially provided with rod slot on the cylndrical surface on its top and rod slot diameter is less than valve collet internal diameter.