US2308413A - Valve guide remover - Google Patents

Description

Jan. 12, 1943.v H. A. BERKMAN yVALVE GUIDE` REMovER Filed May 22, 1941 .fffm

Patented Jan. 12, 1943 'rss-r "ALVE GUIDE REMOVER Herbert A. Berkman, Chicago, Ill., assignor to Zim Manufacturing Company, a corporation of .Illinois Application `May 22, 1941, Serial No. 3945593 (Cl. .Z9-86.3)

2 Claims.

In a common-type of `automobile engine the intake and exhaust valves for the cylinders seat downwardly upon-portions ofthe engine block lying beside the cylinders, and have valve stems extending down through long guides or bushings positioned at a substantial distance below the .valves when the latter are closed; the bushings having downward extensions arranged within the coil springs by means of which the valves are closed. In order to remove the vvalves it is necessary to remove the bushings along with the valves; this being done by lifting the entire valve unit, including the bushing and the valve spring, out of the engine block. When such a valve unit is installed, it is secured, against being so lifted,

vby means of a key in the form of a flat washer having a section removed at one side to permit the washer to kbe slipped laterally upon a neck lportion of reduced diameter on the bushing. This key is normally seated within a recess in the lower face of that portion of the cylinder block through which the valve extends, and cannot be removed without first forcing the bushing down. In service, thesebushings are subjected to ysuch severe conditions that they become frozen to the surrounding metal of the cylinder blocks, so that considerable force is needed to move them. There are several ways in which the bushings Vcan be driven down far enough topermit the 'keys to be withdrawn, but even then it is very difficult to drive the bushingsup; this being due to the restricted character ci the space in which a lifting tool must operate, particularly in V-typey engines.

The object of the present invention is toproduce a simple and novel tool forforcing the valve guides or bushings upwardly land outwardly from their working positions, after the removal of the keys that hold them down, to freefthem and the valves with which they are associated from the cylinder block.

The type of engine to whichmy improved tool is especially adapted is one of the `V-type in which the valves are arranged along opposite t sides of a valley in the cylinder block. In accordance with my invention, the body of the tool comprises two sturdy arms hinged togetherat one end and long enough toextend from a point in the cylinder block adjacent to the lower end of one of the valve stems out through the valley along the The freeends .of the larmsare provided `with jaws to embrace the valve spring, and one of the jaws is provided with what may be termed'an auxiliary jaw, overlying the same and adapted to be slipped between the coils of the spring underneath the lower end of the guide or bushing. A long operating lever is hinged at one end to the upper of two arms, near the jaw end of Ythe latter, and is provided with a cam to exert a powerful spreading force on the arms when the lever is pulled backward toward the hinge end of the arms. By shaping the parts so that the lever may stand aboutA at right angles to the arms when the jaws engage with each other, it is vpossible to insert the tool in the valley of the cylinder block so as to rest at one end in the bottom of the valley, while the lever extends out through thetop of the valley close to the valve which is to be removed; .thereby providing a firm support for the inner end of the tool and suilcient room for a full sweep of the lever across the valley toforce the bushing up and out.

The various features of novelty whereby my invention is characterized will hereinafter be pointed out with particularity in the claims; but, for a full understanding of my invention and of its objects and advantages, reference maybe had to the following detailed description taken in connection with the accompanying drawing, wherein:

Figure 1 shows my improved tool inside elevation in operative relation to a valve bushing mounted in a V-type cylinder block', a portion of which is shown in section; Fig. 2 is a section on line 2-.2 of Fig. 3, on a much larger scale than Fig. 1, the tool being shown in the same condition as in Fig. 1, and fragments of the valve device and cylinder block being shown; Fig. 3 is a top plan view of the tool, the operating lever being shown in section; and Fig. 4 is a bottom plan view of the jaw end of the lower arm of the device.

Referring to the drawing, I represents a -fragment of the cylinder block of a V-type internal combustion engine containinga valley 2 opening out of the top thereof. The walls of the valley overhang the latter at the top, as indicated at 3 and 4 and, through each Yof these cverhanging portions extends a row `of valves. Only a single valve is shown, as will be understood that this may represent one row while the second row lies on the opposite side of the valley at an angle of ninety degrees or more to the plane of the rst row. It will be seen that the part3 contains a bore 5 extending entirely through the same from top to bottom. Fitted within this bore isavalve stemguide. or bushing 6 .divided longitudinally into two sections. The top of the bore is adapted to be alternately opened and closed by a valve 'I whose stem 8 extends down through the bushing or guide. Surrounding the part of the valve stem below the bushing, as well as the reduced lower portion of the bushing that extends down below the member 3, is a compression spring 9. The usual valve-actuating tappet I0 is mounted in the cylinder block below and in axial alignment with the valve stem. As will hereinafter appear, I employ the shoulder II on the cylinder block around the top of the tappet as one resting point for my tool, while the other resting point I2 is at the top of the valley and on the inner edge of the overhang 4. All of these parts are of well known construction and have been illustrated and described simply to explain the purpose and manner of use of the tool constituting the present invention.

Since the valve guides or bushing become rusted to the cylinder blocks so as to form almost an integral part of the latter, great force is required to press them out through the topof the block. Consequently, a tool for this purpose must be very rugged. My improved tool is therefore formed of two heavy, sturdy arms I4 and i5, respectively. The upper arm has a long central slot extending from a point near one end out through the opposite end, and the lower arm has one end reduced in width so as to fit into the open end of the slot. A hinge pin I6 extends through the inter-engaged ends of the two arms, thereby permitting the arms to swing relatively to each other. At the free end of each arm is a jaw, indicated at Il and I8, respectively. These jaws overlie each other and may be alike since their purpose is to embrace the lower end of the spring 9 while the jaw on the arm I4 is resting on the shoulder II and the body of the arm is resting on the shoulder l2 near the hinge end of the tool. Overlying the upper jaw and xed thereto is a thin steel plate I9 provided in the front edge with a notch that is only large enough to embrace the valve stem. To do this, the plate must be inserted between adjacent coils of the spring, as shown in Figs. 1 and 2.

The parts are so proportioned that after the guide or bushing has been driven down far enough to permit the withdrawal of the key (not shown), from the groove I3 in the bushing, the I tool may be slipped in place with the plate I9 lying below and in engagement with the lower end of the bushing. If now a force is exerted tending to spread the free ends of the arms apart, only the upper arm can move because the lower arm rests solidly on the cylinder block and, therefore, when the force becomes great enough, the bushing is pushed up out of its seat. The power for spreading the arms is provided by a long lever 2| which extends down into the slot in the upper arm toward the free end of the latter and is secured by a sturdy hinge pin 22 passing through the arm and the lever. The extreme lower end of the lever is in the form of a cam 24 which rests on top of the lower arm. This cam is so shaped that the lever may stand at about right angles to the upper arm when the two jaws are engaged with each other, as in Figs. 1 and 2; thus permitting the tool to be inserted in the Valley of the cylinder block and leaving the lever free to make a complete working stroke. It will be seen that the distance between the fulcrum of the cam and the outer end of the handle is greater than the distance between the hinge pin 22 and the outer end of the handle, so that one arm of the lever comprises the entire length of the handle device and cam, while the length of the other arm is very short, equalling the distance between a hinge pin and a line drawn at right angles to a line extending from the fulcrum to the outer end of the handle. This provides for an enormous multiplication of the operating force applied to the free end of the handle. The lower arm is preferably provided in the top thereof with a deep depression 25 about as wide as the thickness of the cam and of suliicient length so as not to obstruct. the movements of the cam. This produces an interlock between the two arms to prevent relative sidewise movements which might otherwise take place upon the application of pressure to the tool. Furthermore, I prefer to place in the bottom of this depression a wearing plate 26 upon which the cam rides, thereby protecting the body portion of the arm against the wear which would otherwise take place.

The two arms of the tool are preferably yieldingly connected together so that the jaws will remain in contact until forcibly spread apart. This can conveniently be accomplished by means 0f a small tension spring 2l extending down through the forward end of the slot in the upper arm and into an underlying hole 28 in the lower arm. The upper end of the spring may be connected to a pin 29 fixed in the upper arm, while the lower end of the spring may be provided with a hook 30 engaged in alittle hole 3! sunk into the metal of the arm beside the large hole or opening 28. Also, for the sake of ease of manufacture, the upper arm of the tool is preferably made in two parts symmetrically disposed on opposite sides of a longitudinal vertical plane. In this way the slot is obtained by cutting away the inner sides of the two halves from the rear end to a point near the jaw portion so that, when the two halves are secured together, the rearwardly-extending bars thereof are spaced far enough apart to receive the rear end of the lower arm. With this arrangement, the hinge pin serves to secure together the rear ends of the two halves of the upper arm, so that only a single screw, such as indicated at 32, is needed near the front end to complete the attachment of the two halves to each other.

The manner of using the tool will now be clear. In Fig. l the bushing is shown as having been driven down far enough to have permitted the withdrawal of the key from the groove I3 in the bushing. The tool is shown as having been placed in working position with respect to the valve unit, including the bushing. All that need now be done is to pull the lever in the clockwise direction and thus force the jaw I8, and with it the entire valve unit, up until the main part of the bushing is lifted above its seat or bearing in the bore 5. When this has been done, the valve unit may be lifted out bodily.

While I have illustrated and described with particularity only the single preferred form of my invention, I do not desire to be limited to the exact structural details thus illustrated and described; but intend to cover all forms and arrangements which come within the definitions of my invention constituting the appended claims.

I claim:

1. A tool for the purpose described composed of two sturdy arms hinged together at corresponding ends, the free ends of the arms being in the form of jaws large enough to embrace the spring surrounding a valve stem in an internal combustion engine, a steel plate thin enough to be inserted between adjacent coils of said spring overlying and xed to the top of the upper jaw, said plate having in the forward edge a central notch large enough to receive the valve stern, the upper of said arms containing a long longitudinal slot extending through the same from top to bottom, the lower arm having in the top a recess extending lengthwise thereof, a long lever having its lower end extending through the forward end of said slot and into said recess so as to contact with the lower arm at the bottom of the recess, a hinge pin connecting the lever to the upper arm, the lower end of the lever being in the shape of a cam that spreads the jaw ends of the arms apart when the lever is pulled rearwardly.

2. A tool for the purpose specied comprising a pair of sturdy arms hinged together at one end and having registering jaws at the other end, a long handle hinged at one end to one of the arms near said jaws, the hinged end of the handle being in the shape of a cam curving around said hinge axis, the second jaw having a longitudinal groove about as wide as the thickness of the cam in the upper edge thereof, said cam resting on said second arm at the bottom of the groove, and the point of contact between the cam and said second arm being farther away from the outer end of the handle than is the hinge axis of the cam.

HERBERT A. BERKMAN.

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