US2262075A - Valve seat grinding stone, sleeve, and pilot - Google Patents

Description

Y h/I TNESS Nov. 11, 1941. c, w gb5 2,262,075

VALVE SEAT GRINDING STON E, SLEEVE, AND PILOT Filed April 10, 1941 2 Sheets-Sheet l GLEN/v Cf IA/ILHIDE ilk/1mm v Nov. 11, 1941. e. CFWILHIDE Y VALVE SEAT GRINDING STONE, SLEEVE, AND PILOT 2 Sheets-Sheet 2 Filed April 10, 1941 GLENN C; MAI-ll Patented Nov. 11, 1941 UNITED STATES PATENT OFFICE VALVE SEAT GRINDING STONE, SLEEVE,

PILOT Application April 10, 1941, Serial No. 387,793

AND

Claims.

The invention relates to valve seat grinding. In accordance with the existing practice which involves rotation of a grinding member or stone in contact with the valve seat, the stone is mounted on a sleeve which rotates and slides on a pilot in the form of a shaft or stud secured in fixed relation to the valve stem guide and aligned with the axis of the guide and seat. The sleeve and the stone are driven by a driving tool which is usually portable and power operated.

While this type of pilot and stone sleeve have been in extensive use for a considerable period there is at the high speeds now employed an excess of friction and wear between the pilot and the inner bearing of the sleeve and these conditions are aggravated by particles of steel and emery dirt which enter between the two surfaces. A large proportion of the valve seats thus treated are formed in hardened valve seat inserts which are of frequent occurrence in modern practice in the construction of. internal combustion motors.

While the provision of an inner sleeve mounted on the pilot with anti-friction bearings between the inner and outer sleeves gives an improved operation, there is a tendency to rotation of the inner sleeve on the pilot due to the drag of the anti-friction bearing with resulting wear between the inner sleeve and the pilot which is increased by the presence of particles of steel and emery dirt which is difficult to exclude from this area. The high speeds of 10,000 to 12,000 revolutions per minute at present employed in this work result, particularly in the presence of the steel dust and emery dirt referred to, in a comparatively short period of use, in wear sufiicient to throw the stone and sleeve off center to the detriment of the quality of work produced.

The construction to be illustrated and described provides an improved mounting of the. inner sleeve on the pilot whereby rotation of the inner sleeve is prevented and steel particles and emery dirt more thoroughly excluded. This improved construction also provides increased freedom of motion of the sleeve and stone in the direction of the pilot and valve guide axis which maximum of efficiency in view of the short sleeve seat 2,

lengths which conditions permit, the axial alignment of the outer and inner sleeves and of the stone with the valve guide.

It is notable that all wear due to rotation of the stone sleeve and the inner sleeve is confined to these bearings, which, due to the improved arrangement, show practically nowear and no loss of alignment or increased play.

While the sleeve is particularly adapted for use with a valve seat grinding stone, it is also adapted for use with a valve seat reamer and the stone or reamer may be referred to as a valve seat surfacing member. I

In the accompanying drawings, I have illustrated two forms of stone sleeve and pilot embodying the features of my invention.

In the drawings:

Fig. 1 is a vertical section on the axis of the stone sleeve and stone and valve seat being ground, the pilot being illustrated partly in sec tion and partly in elevation.

Fig. 2 is a horizontal section on the lineZ-Z in Fig. 1.

Fig. 3 is a top plan view.

Fig, 4 is a view similar to Fig. 1 but illustrating a modified form of the invention.

Fig. 5 is a section on the line 55 in Fig. 4 looking downwardly.

Fig. 6 is a top plan view of the construction shownin Fig. 4.

Referring to the drawings by numerals, each of which is used to indicate the same or similar parts in the different'figures, and having particular reference to Figs. 1, 2, andB', the construction shown includes in Fig. 1 a fragmentary portion of cylinder casting I of an internal combustion motor, the fragment illustrated having a valve seat 2v which may be either an intake or exhaust valve seat. The illustration also includes the valve stem guide 3 bushed in the usual man- The valve seat grinding apparatus shown also comprises a pilot 4 secured in stationary. position in the guide 3 in any suitable manner whereby the axis of the pilot is held in alignment or as closely as possible in alignment with the axis of the valve stem guide and valve seat.

The upper end of this pilot located at 5 is grooved or splined at 6 on opposite sides or in any suitable manner, the grooves as shown being parallel to the axis and of outwardly flaring crosssection and extending downwardly toward the grinding stone 1 which is mounted. in any suitable manner in grinding relation with thevalve alent socket II.

In the form shown there is an inner sleeve 8 mounted on the upper end of the pilot, this sleeve is provided with balls 9 held in radial pockets or holes l arranged or spaced in circumferential direction in conformance with the arrangement of the grooves or splines 6. These balls are held in the pockets and the pockets are closed at their outer ends by means of a band or ring II which fits closely about the sleeve engaging a suitable seat thereon at 12. The ring or band H may be positioned as to its lower edge M by means of an upwardly disposed shoulder on the inner sleeve 8. The inner sleeve 8 is thus restrained from rotation on the pilot 5, a free frictionless rolling motion in the direction of its axis being provided, variation of details being contemplated.

The outer sleeve l6 which is mounted on the inner sleeve 8 and carries the stone in a manner to be described, is provided at its upper end in any suitable manner with a hexagonal or equiv- This socket may, for example, be formed in a block I8 threaded into the upper end of the stone sleeve [6 or otherwise secured as ball bearings 22.

In the form of the invention shown the block or socket member 18 is screwed down onto a circular plate 20 which is thus forced downwardly against the outer race 2| of the ball bearing 22 which race is positioned by internal peripheral shoulder 22. The inner race of said bearing as shown is formed on the upper end of the inner sleeve 8. To give better alignment of the sleeves and more permanent centering, the upper ball bearing 22, in the form of the invention shown,

may be provided with two sets of balls 24 and 25, one above the other, and said bearing 22 is preferably located at or near the upper or outer ends of the sleeves 8 and IS.

The lower end of the outer sleeve I6 is supported and accurately centered on and with the inner sleeve 8 in any suitable manner. In the form shown, there is an anti-friction bearing in the form of a needle roller bearing 26 comprising an outer race 21 resting against the inner surface of the outer sleeve l6, the outer surface of the inner sleeve 8 serving as the inner race, providing for reduced diameter at this end of sleeve Below the roller bearing 26 the outer sleeve is closed in a suitable manner as by the inwardly projecting peripheral shoulder 28 Which, in the form shown, may be grooved internally at 29 to provide for any suitable sealing device.

In valve seat grinding, perfect alignment or an alignment as nearly perfect as possible of the grinding axis with the valve stem guide is a primary essential and is dependent on the alignment of the stone sleeve axis with the pilot axis.

The radial type of air craft engine motors where the cylinders and valve chambers are in one piece presents an instance of extreme difficulty in that the pilot must be inserted from within the cylinder, and the stone sleeve must be passed over the pilot an angle type of driving tool being used. It is necessary when working on such motors, because of the relatively small diameter of the cylinders to have the stem of the pilot and the stone sleeve itself of extremely short length in order to conform to these conditions. This naturally reduces the overall length of the bearing between the pilot and stone sleeve and increases the chance of misalignment. In the stone sleeve illustrated and described, the maximum amount of overall bearing length available in proportion to the overall length of sleeve and pilot has been attained together with the most accurate and permanently maintained alignment between the inner and outer sleeve that can be had within these dimensions. Thi is accomplished by placing the lower bearing as close to the lower end of the sleeve as possible, the said bearing being, in the form shown, extended downwardly to a point near the bottom of the stone and placing the upper bearing, i. e., the one remote from the stone at or near the upper end of the inner sleeve. The roller type of bearing permits reduction of the diameter of the outer sleeve at its lower end 38" for insertion in the stone.

In the form shown in Fig. 1, the lower end of the outer sleeve is threaded at 30 and the stone 1 is provided with an insert 3| having a corresponding internal thread at 32, the stone being tightened up against a downwardly disposed shoulder 33 on the outer sleeve l6. Above the flange 33' are flattened surfaces 33" for engagement by a Wrench.

The inner surface 34 of the inner sleeve 8 should be fitted as closely to the outer surface 35 of the pilot 4 as freedom of axial motion'of the sleeve on the pilot will permit, thus contributing to the accurate centering of the stone and alignment of the axis of the same with the valve guide axis and excluding grit.

It may be noted that in the construction thus described the outer rotary sleeve is, except for the details, as the insert or block I8, which provides for the driving engagement, shown in the form of socket H and the outer race 2| of the ball bearing 22 with its cover plate 28 formed in a single piece.

The valve seat grinding stone sleeve indicated in a general Way by reference character 23 consists of the outer sleeve 16 and. inner sleeve 8 the latter mounted for free axial motion on the pilot to permit lifting of the stone but being restrained against rotary motion and accurately centered on thepilot. It is also of importance inits contribution to the result that the bearings whereby the outer sleeve 16 is rotatively mounted on the inner sleeve 8 are as Widely spaced or extended in the direction of the axis as the overall length of the outer sleeve will permit. The bearings are completely enclosed and closely seated to exclude dirt and steel dust.

In Figs. 4, 5 and 6, I have illustrated a form of the stone sleeve 40 which is at present regarded as the preferred form. This consists of an outer sleeve 4| and an inner sleeve 42 which is nonrotatively mounted on the' pilot 43 to slide in the direction of the pilot axis. The inner sleeve may have any suitable non-rotative and axially sliding connection with the pilot. The form of inner sleeve mounting, shown in Figs. 4, 5 and 6, is similar to that illustrated in Fig. 1, in that it includes splines or grooves 6 inthe pilot and balls 9 seated in the inner sleeve and rolling in the said grooves or splines 6.

These figures of the drawings, as distinguished from the construction previously described, show the outer sleeve 4| as made in two sections -44 and 45 which are threaded together at 46,

the upper section 44 being the external section and being tightened downwardly against a shoulder 4'! formed on the lower or inner section45.

.The inner section 45 in turn bears at its upper end 48 against the outer ball race 49 which is forced upwardly against a downwardly disposed.

f shoulder 50 on the inside of the upper or outer section 44. The said outer race also supports the plate which is forced upwardly against a second shoulder 52 also on the inside of the outer or upper section 44 of the outer sleeve.

The shoulders 50 and 52 just referred to are peripherally arranged and it may be noted that.

the driving connection shown in the form of a hex socket 54, any suitable driving connection being usable, is formed in or on a block or other member 55 which may be pressed into the opening 56 formed in the upper end of the outer sleeve,

the details being capable of wide variation.

A further distinction between the two forms shown resides in the provision at the lower end of the inner sleeve 42 between the same and the outer sleeve 4| of bearing rollers 51 shown as having journals 58. These rollers may be described as adapted to be assembled loosely within the casing and held in place by upper and lower rings 59 and 60 shown as provided with inner peripheral flanges 6| which may engage the journals 58. The rings 59 and 60 are pressed into the casting, the ring 69 being used to complete the assembly, 1. e., to seal the bearings and thespace 63 between the inner and outer sleeves and below the inner sleeve. It may be noted that ing to seal the outer sleeve beyond and below the corresponding end of the inner sleeve 42 whereby the sleeves 'are held in assembled relation and the space between the pilot and the outer sleeve at its lower end is completely closed and'all bearings are protected.

.. Any suitable packing or sealing means may be used between the rings 59 and 60, the upper and lower rings 59 and 60 being relied upon as dust "sealing members as well as retaining members for the bearing.

"The roller bearings 51 are spaced in an axial direction as far from the upper bearing or ball bearing 64 as the permissible over-all length of the stone sleeve 40 determined by conditions to be encountered in operation will permit.

The construction shown in Figs. 4, 5 and 6 provides an improved dust seal between the outer sleeve and pilot and below the inner sleeve wherebyall bearings are protected and the separable feature of the outer sleeve provides for convenient assembly of this sealing feature as well as the bearings and for easy replacement of all "parts.

The operation of the construction shown in Figs. 4, 5, and 6 is closely similar to and substantially identical with that of Figs. 1, 2 and 3.

According to the usual practice described in the Neldner Reissue Patent No. 19,013 and Preston Patent #2,056,483 the pilot is secured in the valveguide, extending upwardly through the 'seat and the sleeve assembly 23 with the stone attached is-passed downwardly over the upper end of the pilot providing a non-rotative sliding engagement of the inner sleeve with the pilot,

the stone is thus brought to rest on the seat. ,Suitable grinding motion of the stone is provided by a rotative device to be connected in driving relation with the outer sleeve inanysuit- Letters Patent is:

able manner, lifting at intervals as described being desired.

The advantages, accomplishment and pur- I understood, however, the specific terms herein are used in a descriptive rather than in a limiting sense, the scope of the invention being defined in the claims.

What I claim as new and desire to secure by 1. In a valve seat surfacing apparatus for poppet valve seats the said apparatus having a pilot adapted to be secured in axial alignment with the valve stem guide, an inner sleeve adapted to surround and to be mounted on the pilot and means whereby said sleeve is non-rotatively connected to the pilot with freedom of movement in an axial direction, an outer sleeve mounted on the inner sleeve and having means for securing a valve seat surfacing member thereto and bearings whereby the outer sleeve is rotatively. supported on the inner sleeve.

2. In a valve seat surfacing apparatus for poppet valve seats the said apparatus having a pilot adapted to be secured in axial alignment with the valve stem guide, an inner sleeve adapted to surround and to be mounted on the pilot and means whereby said sleeve is non-rotatively connected to the pilot, an outer sleeve mounted on the inner sleeve and having means for securing a valve seat surfacing member thereto and bearings whereby the outer sleeve is rotatively supported on the inner sleeve, having freedom of movement in an axial direction.

3. In a valve seat surfacing apparatus for poppet valve seats the said apparatus having a pilot adapted to be secured in axial alignment with the valve stem guide, an inner sleeve adapted to surround and to be mounted on the pilot and means whereby said sleeve is non-rotatively connected to the pilot with freedom of movement in an axial direction, an outer sleeve mounted on the inner sleeve and having means for securing a valve seat surfacing member thereto at one end and bearings whereby the outer sleeve is supported on the inner sleeve, said bearings being spaced apart and located adjacent the opposite axial ends of said sleeves respectively.

4. In a valve seat surfacing apparatus for poppet valve seats the said apparatus having a pilot adapted. to be secured in axial alignment with the valve stem guide, an inner sleeve adapted to surround and to be mounted on the pilot and means whereby said sleeve is non-rotatively connected to the pilot with freedom of movement in an axial direction, an outer sleeve mounted on the inner sleeve and having means for securing a valve seat surfacing member thereto at one end and bearings whereby the outer sleeve is supported on the inner sleeve, said bearings being spaced apart and located adjacent the opposite axial ends of said sleeves respectively, the outer sleeve being of reduced diameter at one end which is adapted to be inserted in the surfacing member, the bearing at said end being a roller bearing to provide for such reduced diameter.

5. In a valve seat surfacing apparatus for poppet valve seats the said apparatus having a pilot adapted to be secured in axial alignment with the valve stem'guide, an inner sleeve adapted to be mounted on the pilot and means whereby said sleeve is non-rotatively connected to the pilot, u

an outer sleeve mounted on the inner sleeve and having a driving connection .at one end and -means' for securing a valve seat surfacing memberonand surrounding the outer stem near the :opposite end and bearings adjacent the opposite ends of said sleeve whereby the outer sleeve is supported on the inner sleeve, one of said bearings being within the surfacing member and of small diameter roller type and the other bearing being a relatively large diameter ball bearing.

6. In a valve seat surfacing apparatus for poppet valve seats the said apparatus having a pilot adapted to be secured in axial alignment with the valve stem guide, an inner sleeve adapted to be mounted on and to surround the pilot and having means whereby this sleeve is non-rotatively connected to the pilot, an outer sleeve mounted on the inner sleeve and having means for securing a valve seat surfacing meme :ber thereto and bearings whereby the outer sleeve; 'is supported on the inner sleeve, said bearings :being widely spaced in the direction of the length of the inner sleeve and comprising a relatively large diameter bearing of the double race ball type remote from the surfacing. member and a bearing in the form of a small roller bearing adjacent the surfacing member providing for a reduced diameter of the outer sleeve where it engages the said member, the outer sleeve carry- ;ing said member having freedom of movement in an axial direction.

7. In a valve seat surfacing apparatus for poppet valve seats the said apparatus having a pilot adapted to be secured in axial alignment with the valve stem guide, an inner sleeve adapted to be mounted on the pilot and means whereby this sleeve is non-rotatively connected to the pilot with freedom of movement in an .axial direction, an outer sleeve mounted on the ;-inner sleeve and having a driving connection at one end and means for securing a valve seat surfacing member thereto near the other end and bearings whereby the outer sleeve is rotatively supported on the inner sleeve and means for sealing the outer sleeve with the pilot said seal- .ing means being beyond the inner sleeve at the end where said member is located.

8. In a valve seat surfacing apparatus for poppet valve seats the said apparatus having a pilot adapted to-be secured in the valve stem guide, an inner sleeve adapted to be mounted on the pilot and means whereby this sleeve is nonrotatively connected to the pilot with freedom of movement in an axial direction, an outer sleeve, mounted on the inner sleeve and having a driving connection and means for securing a valve seat surfacing member to said outer sleeve and bearings whereby the outer sleeve is supported on the inner sleeve, said bearings comprising a ball bearing near said driving connection and a bearing of small diameter near the opposite end of said inner sleeve and the outer sleeve being inserted in and being of reduced diameter within the surfacing member the outer sleeve being in two sections, one section entering Within the other, one section containing the ball bearing and the other section containing the roller bear- 9. In a valve seat surfacing apparatus for poppet valve seats the said apparatus having a pilot adapted to be secured in axial alignment with the valve stem guide, an inner sleeve adapted to be mounted on the pilot, said-pilot being-grooved in the direction of its axis and anti-friction ballsseated in said inner sleeve and operating in said grooves, an outer sleeve enclosing and-rotatively mounted on said inner sleeve and having a driving connection at one end and means for mounting a valve seat surfacing member on said-outer sleeve at a location remotefrom said driving connection. 10. In a valve seat surfacing apparatus fo poppet valve seats the said apparatus having a pilot adapted tobe secured in axial alignment with the valve stem guide, an inner sleeve adapted to-be' mounted on the pilot, said pilot being grooved in the direction of its axis and -anti-friction-balls seated in said inner sleeve and rolling in said grooves, an outer sleeve enclosing and rotatively mounted on said inner sleeve and "having a driving connection at one end and means for mounting a valve seat surfacing member on said outersleeve at a location remote from said driving connection, said rotati-ve mounting of the outer sleeve on the inner sleeve comprising anti-friction bearings spaced in the direction of the axis in correspondence with the length of the inner sleeve.

11. In a valve seat surfacing-apparatus for poppet valve seats having a pilot adapted to be secured in axial alignment with a valve seat guide, an inner sleeve with means securing the sleeve in free sliding non-rotative engagement with the pilot, an outer sleeve having bearings at its opposite ends whereby it is supported on the inner sleeve, one end having a driving connection and 'a large .diameter bearing, the opposite end having a small diameter bearing of reduced diameter and adapted for insertion in a valve seat surfacing member whereby the latter is secured to the sleeve, the outer'sleeve consisting of inner and outer sections engaged in telescopic relation.

12. In .a valve seat surfacing apparatus for .poppet valve seats having a pilot adapted to be secured in axial alignment with a valve seat guide, an inner sleeve with means securing the :sleeve in free sliding non-rotative engagement with the pilot, an outer sleeve having bearings at its opposite ends whereby it is supported on the inner sleeve, one said end having a driving connection and a larg diameter bearing, the opposite end having a small diameter bearing of .reduced diameter and adapted for insertion in a valve seat surfacing member whereby the lat-' .ter is secured to the sleeve, the outer sleeve consisting of inner and outer sections engaged in telescopic relation, the large diameter bearing being in the outer section and the small diameter bearing in the inner section and a member of the large diameter bearing being secured between the inner and outer sections.

13. In a valve seat surfacing apparatus for poppet valve seats the said apparatus having a pilot adapted to be secured in axial alignment with' the valve seat, an inner sleeve mounted on the pilot and an outer sleeve mounted on themner sleeve, and having means for securing a valve seat surfacing member thereto and bearings whereby the outer sleeve is rotatively supported on the inner sleeve in axial alignment with the valve seat and means for excluding dust and grit from said bearings, said outer sleeve and valve seat surfacing member having freedom of movement in an axial direction relatively to the valveseat.

stone, said latter means having a driving connection for said stone.

15. In a valve seat grinding apparatus for poppet valve seats, a pilot and means whereby it may be secured in the valve stem guide with its axis aligned with the valve axis, said pilot having a groove parallel to its axis for non-rotative engagement with a sleeve mounted to slide on the guide and adapted to provide a rotary 10 support for a valve seat grinding stone.

GLENN C. WILHIDE.

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