US2093771A

US2093771A - Method of making copper cooled valves

Info

Publication number: US2093771A
Application number: US518666A
Authority: US
Inventors: Archie T Colwell
Original assignee: Thompson Products Inc
Current assignee: Northrop Grumman Space and Mission Systems Corp
Priority date: 1931-02-27
Filing date: 1931-02-27
Publication date: 1937-09-21
Anticipated expiration: 1954-09-21

Description

Sept. 21, 1937. A. T. COLWELL METHOD OF MAKING COPPER COOLED 'VALVES Filed Feb. 27, 1931 Patented Sept. 21, 1937 UNITED sTATEs PATENT OFFICE METHOD F MAKING COPPER COOLED` VALVES Archie T. Colwell, Cleveland, Ohio, assignor to Thompson Products, Incorporated, Cleveland, Ohio, a corporation of. Ohio Application February 27, 19131, Serial No. 518,666

9 Claims. (Cl. 29-156.7)

chambers of automotive engines closely approximate the temperatures to which the metals used in the manufacture of valves are heated in such manufacture. The gases which pass the exhaust valves maintain` the exhaust passageway at a temperature of around 1600 F. for ordinary engine speed. These gases'have a very destructive effect on the valves, causing corrosion and warping and producing a destructive change in the metal of the valve. Since these gases are directed against a portion of the valve which includes the upper portion of its stemand the lower portion of the head, it has been a problem for valve mar :facturers to devise a means of cooling this portion of thevalve.

This cooling has been accomplished in several Ways such as providing a shield about this portion and also by filling the stem of the valve'with a cooling medium which will draw the heat to a portion of the valve which may be cooled by outside means.' The first of these methods is'objectionable because its effect depends upon the formation of a dead air space between the protecting shield and the valve. In this type of valve the heat being directed against the protecting shield will have a destructive action on the shield and will in time eliminate the dead air space. The other method of cooling the valve, as heretofore practiced, while more permanent in nature, 35 has been found not entirelyl satisfactory for the reason that it involves a considerable expense and careful planning or else the cooling medium ls not very eective.

According to the present invention, a simple 40 and inexpensive means for cooling the portion of the valve against which the exhaust gases. are directed is provided.

It is an object of the present invention to produce a metallic cooled valve by a method which is inexpensive, expedient and adapted for use in large scale production of valves.

' It is a further object of this invention to produce a cooled valve by a ymethod which involves the insertion of the cooling medium in the valve 50 blank and theforming of the valve with the insert therein.

It is a particular object of this invention to produce a metallic cooled valve by a method which includes inserting a metallic cooling medium in 55 the valve blank and extruding the composite blank to form the valve.

This invention (in a preferred form) is illustrated in the drawing andhereinafter more fully described.

On the drawing:

Figure lvi's a sectional view of Aa metal blankl with an insert therein and a plate welded thereto. Figure 2 is a sectional view of a' modified form of a blank. p

Figure 3"is a sectional view of a further modified form of a blank.

Figure 4 is a sectional view of a valve formed by extruding the blank of Figure 2.

Figure 5 is a fragmentary sectional view of the end of a valve formed by extruding the blankv of Figure 1.

Figure 6 is a sectional view of the valve showing the end of the stem in final form.

Figure 'I is a fragmentary sectional view of the end of the stem of a valve showing a modification in which the insert extends through the. end of the valve.

As shown on the drawing:

In carrying out this invention, a blank i is formed as by casting or by cutting a slug from a bar of rolled stock. A suitable recess 2 is drilled into the blank i. drical and concentric with the blank i, extending through one end of the blank and for .a sub-- stantial distance within the blank. An insert 3 is then placed in the recess 2 and forced to the inner end thereof so that when the valve is formed, in a. manner hereinafter to appear, the insert will extend throughout the stem and a short distance into the-head portion.

In Figure 1, the insert 3 is shown as completely filling the recess 2 and a plate l is Welded to the end of the blank through which the recess 2 extends over the end of the insert. The purpose` of the plate il is to preventY oxidation of the insert 3 when the blank is heated preparatory to the forming of the valve.

The blank i is formed of any suitable valve material, such as tungsten steel, or nickelchromium steel. The insert 3 is made of any suitable metal such as copper which has a relatively greater rate of heat conductivity than that of the metal of the blank. The plate '6 may be made of any suitable material which will forma bond with the metal of the blank. but is preferably made of a steel having great weary resistance qualities, as this part of the blank 'is formed into the portion of the -stem which contacts with the operating mechanism.

Figures 2 and 3 show slightly modified forms of the blank. In Figure 2, the metal plat 4 is 'I'he recess is preferably \cylinprovided with a nipple or stud 5 which fits into The composite metal blank thus formed is heated to a forging temperature and extruded through a suitable die. In this operation, the blank may be extruded through a die which will 5 rform the article shown in Figure 4, orin the preferred way, the metal blank is extruded so as to form a stem and a head portion thereon so as to somewhat resemble a finished valve. This intermediate blank is then nished to shape l by any of the known methods.

In either case the extruding process Icauses the formation of a head l and a stem 8. The insert 3 is drawn out so as to form the elongated core 9 within the stem 8. The absence of oxygen or l air together with the high temperature and subsequent extruding, forms a bond or welded joint between the stem 8 and core 9 which has a' rate of heat conductivity closely approximating that of the metal itself whereas an ordinary joint oifers material resistance to the flow of heat.

A portion Il) of the core 9 extends into the head 1.

The metal of the plate 4 is incorporated into the end of the stem as shownat Il.. This portion Il may be finished off and provided with an annular groove I2 as shown in Figure 6.

Figure 5 shows the end of the stem as it is formed when there is but a small plug 6 of metal in the blank, as shown in Figure 3.

Figure 7 shows a modified way of producing the end of the stem. In this case, a length of metal at the end of the stem is removedso that the insert 9 extends through the end of the valve as shown at I3.

l It will be seen that this invention, provides a '55, method of making a valve having an insert of great heat conducting properties which `is economical, simple, and adapted for use in large scale production.'

Many changes may be made in the design and proportion of the parts and I'dorrnot wish to be limitedvotherwisev than is necessary by the prior art and the scope of the appended claims.

I claim as my invention: e

1. The method of making a cooled valve which 45 comprises forming a metal blank with a recess extending longitudinally thereof, inserting a metal having a relatively high rate of heat conductivity in said recess, welding a metal plate to said blank over the end of said recess so as to exclude air from the recess, heating the composite'blank thus formed to a forging temperature and extruding the blank through a suitable die to form a head and stem thereon, the operation being carried out so that the plate forms a portion of the stem and the insert is disposed longitudinally of the stem.

2. The method of making a cooled valve, which comprises forming a blank of a suitable steel for making a valve, drilling a recess in said 60 blank, placing a copper insert in said recess,

welding a metal plate to said blank over the end\ of said recess so as to exclude oxygen from the contacting copper and steel surfaces, heating the composite metallic blank thus formed to forging G5 temperature and extruding the blank through a suitable die to form a head and stem thereon with the copper extending throughout the stem and into the head, the extruding operation being carried out so that the plate forms a portion of the stern and the insert is disposed longitudinally of the stem.

into the stem.

3. 'Ihe method of sealing a metal cooled valve. which comprises heating a valve blank having a recess therein partially filled with a metal of relatively high heat conductivity, inserting a metallic plug in the end of the recess of said blank 5 and extruding the blank to form a valve with the metal of the plug incorporated in the stem of the valve to form a part of the valve stem.

4. 'I'he method of making a cooled valve which comprises forming a recess in a metal blank, 10 placing a metallic insert in the blank, welding a metal plate to the blank over the end of the recess so as to exclude air from the recess, and extruding the blank to form a head and a stem thereon'with the insert extending down the stem 15 and spread out in the head and with the plate forming a portion of the stem.

5. The method of making a cooled valve which comprises forming a metal blank with a recess extending longitudinally from one end thereof into close proximity to the other end, placing a copper insert into said recess, welding a metal plug to said blank at the end of the recess so as to exclude air from the recess, heating the composite blank thus formed to a forging temperature and extruding the blank through a suitable die to form a head and stern thereon with the copper spread out into the head and extending down into the stem and the plug incorporated into the blank metal Vto form a portion of 30 the stem;

6. The method of making a poppet valve having a metal insert of high heat conductivity therein, which comprises providing a metal blank having a recess extending from one end thereof intospaced relation from the other end thereof, placing a metal having high heat conductivity characteristics in said recess and shaping the composite blank thus formed to provide a head and stem thereon withvthe insert metal spread out into the head and .extending into the stem.

7 The method of making a metalcooled valve which comprises providing a metal blank having an axial blind bore therein, placing an insert metal having high heat conductivity characteristics in the bore and shaping the composite blank thus formed to provide a head and stem thereon with the insert metal encased in the blank metal and spread out into the head of the valve and extending axially down the valve stem.

8. 'Iy'he method of making a copper cooled valve which comprises providing a metal blank having a recess therein, filling the recess with copper and shaping the blank to provide a head and Vstem thereon with the copper spread out `into the head to form a mushroom-shaped copper lling encased in the headand extending down the stem. i Y Y 9. The method of making a metal cooled valve which comprises providing a metal blank having ARCI-IIE T. COLWELL.