US1725672A - Pull rod - Google Patents

Description

H Aug. 20, 1929; A. PEGL-AR PULL ROD Filed Jan. 17, 192

INVENTOR A? 4 Pf'Al/Q ATTORNEY Patented Aug. 20, 1929.

UNITED STATES RICHARD A. PEGLAR, OF TORONTO, ONTARIO, CANADA.

PULL B01).

Application filed January 17, 1928.

My invention relates to improvements in operating mechanisms for overhead valves, used on internal combustion engines, and it consists in the combinations, construct-ions, and arrangements herein described and claimed.

An object of my invention is to provide a device of the type described, consisting of a single, integral main operating pull rod, and a novel adjusting mechanism attached to the pull rod, for efficient operation of the valve.

A further object of my invention is to provide a noiseless valve construction in which the valve actuating mechanism is rigidly attached to the valve stem and in which the effective length of the valve stem may be ad justed.

Another object of my invention is to provide a novel lubricating means for the main body of the pull rod.

Other objects and advantages will appear in the following specification, and the novel features of the invention will be particularly pointed out in the appended claims.

My invention is illustrated in the accompanying drawings, forming a part of this application in which Figure 1 is a sectional view of an engine with my improved valve-operating mechanism applied thereto,

Figure 2 is an enlarged detail view of a portion of the valve operating'mechanism,

Figure 3 is a fragmentary sectional view taken substantially on the line 33 of Figure 2,

Figure 4: is a sectional view taken on the line 4--4 of Figure 1.

In the drawings 6' indicates a' cylinder block, of a conventional internal combustion engine, which is supported by a crank case 7, an oil pan 8 is attached to the crank case 7 in the usual manner.

The cylinder block 6 is provided with a vertical rectangular groove 9 in which a pull rod 10 of square cross section is placed. The pull rod 10 is constructed of a single piece of material, and is bent at each end to form horizontal arms 11 and 12. I provide a narrow strip 13 having a groove 14 in which a portion of the pull rod 10 is placed. The strip 13 has apertures through which bolts 15 extend, and the latter screw into the cylinder block 6 thereby holding the pull rod 10 in position.

The arm 11 of the pull rod 10 carries ad- Serial No. 247,396.

justing mechanism for the poppet valve 16, and in order that this mechanism, which will be described in detail later, may function properly, part of the underside of the arm 11 is cut away from the point 17 to the end thereof. Threads 18 are placed on the end of the stem 19 of the poppet valve 16, and are adapted to receive semi-spherical nuts 20, in such a manner that the bases of the nuts abut. The arm 11 carries an adjustable support 21 through which an aperture 22 extends.

The support 21 is attached at one end to the arm 11, of the pull rod 10 by a pair of links 23 and 2 1, which are pivotly mounted on the pins 25 and 26, and at the other end is held by a yoke 27. A thumb screw 28 passes through the yoke 27 and bears upon the arm 11 for adjusting the support 2 relative to the arm 11, thereby securing the nuts 20 between the arm 11 and the support 21. tion of one of the nuts 20 rests upon the support 21, while the other nut bears against the underside of the arm 11, holding the valve 16 correctly adjusted, yet these nuts may roll slightly on the support 21 to insure proper seating of the valve 16. The support 21 is notched on its underside at 29 to form a recess in which a rounded portion 30 of the yoke 27 rests.

A spring 31 is placed under tension between the arm 11 and the engine block 6 for holding the valve 16 normally in its seat.

A strip of felt 32 is interposed between the pull rod 11 and the strip 13 for lubricating the pull rod. Lubricant is splashed by a crank shaft 33 upon the lower end of the pull rod 10 and is rubbed against the felt when the device is operating. Oil may also be forced through the felt from the top of the groove 14;.

The crank shaft 33 drives a train of gears 84c, which in turn drives a cam shaft 35 upon which a cam 36' is mounted forengaging the upper side of the arm 12, when in operation. The cylinder block has a removable head 37 in which a screw threaded plug 38 is placed, and when it is desired to inspect the valve 16, the plug may be removed for this purpose without taking off the cylinder head.

From the foregoing description of the various parts of the device, the operation there: of may be readily understood. When removing the valve 16 from the cylinder 6, the thumb screw 28 is unscrewed and the yoke 27 is removed over the ends of the arm 11 and The rounded porthe support 21, permitting the support 21 to swing downwardly on the pins 26 and the nuts 20 to be removed. The plug 37 is unscrewed from the cylinder head 38 and the valve may be withdrawn for inspection. 7

When the engine is started the train of gears 34 rotates, causing the cam 36 to bear against the arms 12 of the pull rod 10, thereby giving the pull rod a downward thrust, which compresses the spring 31, and unseats the valve 16 allowing the charge to enter the combustion chamber of the engine. As the bearing surface of the cam moves away from the arm 12 the valve is urged into its seat due to the expansion of the spring 31 which was compressed on the downward thrust of the cam 36.

In addition to the advantages mentioned above there is another advantage that is of prime importance. It will be noted that the connection of the valve stem 19 to the arm 11 is such as to obviate the objection which is usually found in valve mechanisms of this type in that there is no hammer action with the resultant noise. The valve stem moves in unison with the arm 11 and is not struck by it. At the same time provision is made for adjusting the effective length of the valve stem 19. In order to do this the nuts 20 may be turned to the proper position and then the yoke 27 may be drawn up by means of the thumb screw 28 so as to hold the nuts in their adjusted position between the arm 11 and the support 21, while at the same time providing a slight roll to insure proper seating of the valve. I

It will be noted that the strip 13 has a lateral bend 13 at the bottom thereof which is secured to the crank case by means of bolts, such as that shown at 13". This lateral strip 13 covers a slot 13 and the strip may be taken off and the pull rod removed without taking down the engine.

I claim:

1. A valve operating mechanism for internalcombustion engines including a cylinder block, a valve disposed in the upper end of the block and having a valve stem projecting therethrough, said valve stem being threaded at one end, a pair of semi-spherical nuts having their fiat'sides in contact with one another andarranged to fit on said threaded end for varying the effective length of said rod, a pull rod slidably carried by the block and having a laterally extending arm, a support having an opening arranged to receive the valve stem, one end of the support being pivotally connected to said arm, and means for adjusting and securing the opposite end of the support whereby the valve stem is held in close contact with the arm.

2. A valve operating mechanism for internal combustion engines including a cylinder block, a valve disposed in the upper end of the block and having a valve stem projecting therethrough, said valve stem being threaded at one end, a pair of semi-spherical nuts having their flat sides in contact with one another and arranged'to fit on said threaded end for varying the effective length of said rod, a pull rod slidably carried by the block and having a laterally extending arm, a support having an opening arranged to receive the valve stem, one end of the support being pivotally connected to said arm, means for adjusting and securing the opposite end of the support whereby the valve stem is held in close contact with the arm, said last-named means comprising a yoke arranged to receive one end of the arm and one end of the support, and means carried by the yoke for forcing the support toward the arm.

3. In a valve operating mechanism, a movable arm, a valve stem threaded at one end, a pair of semi-spherical nuts having their fiat sides in contact with one another and arranged to fit on said threaded end, a supporting member having an opening arranged to receive the stem, links for pivotally connecting said supporting member to said arm at one end, and means carried by the arm for drawing the opposite end of the supporting member toward the arm. 7 j

4. In a valve operating mechanism, a movable arm, a valve stem threaded at one end, H

a pair of semi-spherical nuts having theirflat sides in contact with one another and arranged t0 fit on said threaded end, a support ing member having an opening arranged to receive the stem, links for pivotally connecting said supporting member to said arm at one end, a yoke carried by the arm and arranged to receive the opposite end of the support, and a set screw carried by the yoke and arranged to bear on the arm for drawing one end of the supporting member toward the arm.

Signed at Toronto in the county of York and Province of Ontario, Canada, this 28th day of December A. D. 1927.

RICHARD A. PEGLAR.

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