US1655821A

US1655821A - Valve grinder

Info

Publication number: US1655821A
Application number: US168531A
Authority: US
Inventors: George R Rich
Original assignee: Individual
Current assignee: Individual
Priority date: 1927-02-16
Filing date: 1927-02-16
Publication date: 1928-01-10
Anticipated expiration: 1945-01-10

Description

Jan. 10, 1928. 1,655,821

G. R. RICH VALVE GRINDER File Fe'b. 16, 1927 2- 'j' Patented Jan. 10, 1928.

UNITED STATES GEORGE B. RICH, OFBATTLE CREEK, MICHIGAN.

VALVE GBINDEB.

Application led February 16, 1987. Serial No. 168,531.

This invention relates to valve grinders' and more particularly to the clutch thereof which holds the poppet valve during the process of grinding 'its tapered seating face. Tapered face poppet valves of internal combustion engines seat upon correspondingly tapered valve seats formed in the cylinder blocks of the engines and unless the valves seat perfectly, leaks occur bet-Ween the valves and their seats, thereby causing poor compression with a corresponding loss of power. A poppet valve of this kind is provided with a stem and a disc like head, which is formed with a vtapered seating face as is well understood. In many cases it is preferred to grind the valve stem on a centerless grindf er, because of the great accuracy which is obtained in the method of grinding valve stems with a centerless grinder. The difficulty in holding a valve during the process of grinding .its 'tapered seating face is that of preventing the valve from rotating out of its true axis, and from wabbling or chattering. When held in the ordinary chuck of a valve grinding fixture, the valve is apt to be held ofi center because of the wear on the jaws of the collet and because the stem is sometimes not ground true`- One of the 'objects of my invention is to provide a chuck of novel form for holding the valve stem rigidlyagainst any vibration and for rotating it upon its true axis whereby the tapered seating face thereof may be accurately ground into a true circle. With these ends in view this invention relates to a valve grinderihaving a chuck providedwith a collet for gripping the end of the valve stem and a valve centering collar or collet in which the valve stem is accurately centered and held by a ti ht iit, whereby when the valve is rotated y the chuckit is caused to rotate'on its true center and its tapered seating face may therefore be ground accurately and true. The invention further consists in the several novel features herein` after fully set forth and ciaimed.

The invention is clearly illustrated in the accompanying drawing, in which:

Fig. 1 is a plan of a valve grinder embodying a simple form of the present invention, and showing a valve heid in grinding position therein, certain parts of the fgrindini7 member being broken away; Fig. 2 is tical, longitudinai section taken on 2-2 of Fig. upon a siightiy enier,- ig. 3 is a deta'd sectionai view, in

of the end of the chuck, which contains the st em gripping collar and Fig. 4 is an end view oo ing in the direction of the arrow 4 in Fig. 3 with the valve removed.

Referring to said drawing, the reference character 5 designates the grinding member ofthe machine, which member embodies a grlnding wheel 6 mounted Ona shaft 7, which is journaled in bearings, one of which is seen at 8, and having a belt pulley 9 mounted thereon, belted to a suitable drive pulley, by means of which the grinding wheel may be rotated. These parts comprise the grinding tool of the grinding member, and as usual it is capable of being moved 1n lines parallel with the axis of the shaft and in lmes at right angles thereto whereby the rinding wheel may be fed to and across t e taperedf seating face of the valve A, which is to be ground.

Mounted adjacent to the grinding member is a chuck fixture 10, having a base portion 11 upon which is mounted a head 12. The head is bored longitudinall and the axis of the bore is set at a suitab e an le with respect to the grinding face of t e grinding Wheel 6, an angle of 45 degrees belng here shown, inasmuch as that angle is one of the standard angles of tapered seating faces of poppet valves for internal combustion engines.

Secured in the bore of the head 12 is a bearing bushin 13, in which is rotatively mounted the hollow spindle 14 of the chuck. uo A belt pulley 15 is mounted on the hollow spindle 14.- and is belted to a suitable drive pulley and furnishes the means for rotating` the hollow spindle 14. A. flange 16 on the hollow spindle 14 bears against one end of es the bushing 13, and a collar 17 mounted upon said hollow spindle bears against the other end of said bushing. Nuts 18 threaded upon the outer end of the hollow spindle and bearing against the collar 17, are loe provided for securing the hollow spindie against endafise movement in the bushin in the hollow of the hoilovv spindle A is xediy secured a sieeve 19, which has an interiorly-tapered front end that engages with ion the tapered outer side of the 52,@ of a stem gripping ceiiet 2i. coiiet is adapted to grip the stem e, of the valve A, 'niiet ground. rEhe coilet 2i c i $55,

H i L wise direction by lingers 23 mounted upon a support 2A, which is threadedly secured upon the outer end of the tubular member 22. A. finger actuatinfr collar 2G is slidably mounted on' the hollow spindle 14: and has a tapered end, which engages with the lingers 23 and said collar is arranged to spread the ends ot said lingers apart when forced towards said tin ers to thereby cause said lingers to move t e tubular member 22 in an endvvise outward direction to thereby clamp the jaws of the collet 21 upon the valve stein a. A hand lever 27 fulcrunied upon an arm 28 of-the base 11 and provided with a fork, having pins arranged to engage in a circumferential groove in-the collar 26 provides means for shitting the collar 26 and thus operating the collet 21.

rthe collet 21 is located at a considerable distance away from the outer end ot' the hollow spindle 14C instead of being located at its outer end and isarranged to `grip the valve stem at a place distantly removed from the valve head al, and means are pro- `vided at the extreme outer end ot the hollow spindle 14: for centering and gripping the valve stein at a place adJacent the valve head ai. and said means will now be del scribed.

Fixedly secured in the outer end of the hollow spindle 1li is a bushing 30, which contains a central bore 31 through which the valve stem may be inserted into the collet 21. Said bushing is provided with an externally threaded lange 32 on which is screwed a nut 33 that may be screwed against the outer Ytace ot one ot the clamp nuts 18 to Withdraw the bushing 30 :from the hollow spindle la. rlhe outer end of the bushing 30 is bored out to torni a cavity 34: in Which is secured a valve centering collar or collet 35, Whichhis termed with faws 36 and the jaw portion of the collar 35 is accurately bored to tit the stein (t9 ot the poppet valve. A nut 37 is threadedly secured upon the externally threaded end 38 ot the bushing' 30 and said nut is formed with a tapered inner face 39 'which fits the tapered outer tacos ot the javvs 3@ of the collar 35. Set screws i0 threadedly secured in the nut 37 are arranged to bear against the outer 'faces ci: the collar jaws 3S and provide means whereupon any or all ot said may be adjusted toward or away from the axis oi rotation of the chucl-. Vfhen poppet valves are Lcfrtrund on a centerless stein grinder a very slight taper or 'daring part Lil is ground upon the end et the valve stem adjacent the head.

ot the tion is Wl en ohneA e. d

valve., which tapered ordering porconcentric the asis of the valve. valve is inserted into oecoines tightlv wedged into the *r collar or collet stern is gripped by the collet 21 and the chuck is rotated the valve will therefore be rotated upon the true axis ot the valve stem and any wabbling or chattering thereof is eliminated. lt' desired the collar or collet 35 may be omitted and the bore 3l may extend to the front end ot the bushing 30. ln this case the flaring ground end of the valve stem Wedges directly in the bore ot' the bushing.

inasmuch as the valve stem sometimes becomes tightly wedged in the collar or the collet, means have been provided for freeing thevalve stem from the collets. A simple torni of means has been shown in the drawing and comprises a stem 42 contained in the tubular member 22 and having a reduced end portion t3 of the same diameter or a diameter slightly less than that of the valve stein and arranged to he struck against the saine. rl`he other end of the stern ll2 projects beyond ythe rear end oit' the hollow spindle 14 and is secured to a yoke member elli, as tor instance by nuts i5 threaded on the threaded end ot the stein l2 and grippino' the yoke member between them. Said yo e lll is connected Wit-h the forks of the hand lever 27 by nuts 47. An adjustable collar i6 is threadedly secured upon the outer end et the stern 42 and is adapted to be forcibly brought into contact with the rear end el the tubular member 22 to thereby jar the collet 21 tree in case it may become wedged tightly on the valve stein.

lrthe operation et this device, the stem ot the valve to be ground is inserted through the collar 35 and into the collet 21 and the hand lever 2'? thereupon moved in the direction to clamp the collet 2l upon the valve stein. ln inserting the valve stein into the chuck the attendant torcibly presses the tapered or daring end el ot' the valve stern into a vvedging contact with the collar or collet 35 so as to rnalre a tight ht between the two. lt Will be understood that both the grinding Wheel andthe chuck are in constant rotation. The attendant then moves the grinding Wheel up to the rough beveled seating tace ol the valve head and accomplishes the= grinding operation in the usual grinding away suficien't material to produce a smooth surface. When linished, the tendant moves the hand lever 2'? hack thereby releasing; the collet 2l from the valve stein and in doing; so the yoke del is draivn lorivard su'ilieiently to the forward end of the reduced portion d3 ot the valve ejectsteni. l2 into engagement with the end of he valve and thereby releasing it :troni ts wedged condition with the collet or col- -2 me. f7.1.;

f1 ceive the flaring act form of the construction shown and described, but intend, in the following claims, to point out all of the invention disclosed herein,

I claim as new, ters Patent:

l. In a valve grinder for grinding the tapered seating face of poppetvalves, a rotary valve stem holding chuc t, having an endwise movable collet therein, arranged to grip one end of the valve stem, collet actuating mcans, and a stein centering collar stationarily secured in thel outer end of the chuck, said collar having a cylindrical bore adapted to rehead end of a valve stem and the collet being movable in a direction to wedge the flaring head end of the valve in the cylindrical bore of the collar, whereby the two `ends of the valve stem are tightly held in `centered position in the collar and collet.

2. In a. valve grinder for grinding the tapered seating face of poppet valves. a rotary,

and desire to secure by Letvalve stem holding chuck, having chuck clos.

ing means, a stem gripping collet in said chuck, a collar stationarily secured at the end of the chuck, said collar being formed with radially adjustable endwise engageable centering jaws, and means for radially adjusting the jaws of the collar independently of the chuck closing means.

3. In a valve grinder for grinding the tapered seating face of poppet valves, the combination of a rotary, valve stem holding chuck, having a stem gripping collet therein, collet actuating means, a stem centering member at the end of the'clluck and having a cylindrical bore into which the flaring head end of the valve stemv is moved into a tight y fit by said collet and its actuating means, a

valve ejecting spindle, a single hand lever and operative connections between said hand lever and the collet actuating means and between said hand lever and the valve ejecting spindle whereby the collet actuating means and valve ejecting spindle are actuated simultaneously.

GEORGE R. RICH.