US1900518A - Self-adjusting valve lifter, or tappet - Google Patents

Description

March 3- A. L. PEARSON ET AL 0 5 8 SELF ADJUSTING VALVE LIFTER OR TAPPET Filed April 2, 1931 QOJMUMW MD fi777EZ- L P95754727 :[c/I 557775727 Patented Mar. 7, 1933 r I I I m i j a UNITED STATES PAT w AMEL nrnnnsoii Annzrncos a. ennnannr; or MADISON, WISCONSIN SELF-ADJUSTING VALVE LIFTER, OR 'IAPPET Application filed April 2, 1931., Serial No. 527,180.

This invention relates to improvements in Slidably mounted within the guide 1 is a self-adjusting valve lifters, or tappets. 1 cylinder member 5, the lower end of which One of the objects of the present invention is provided with a closed head 6 having an is the provision of a. self-adjusting valve annular flange 7. The head 6 normally lifter or tappet which positively eliminates engages the cam 8 on the camshaft 9. 5 5 clearance between the lower end of the stem The upper endofthe cylindrical member of areciprocatingvalve, or push rod, andi's 5.extends up into the receptacle 3 to a point positioned between the valve stem or push adjacent the upper end 21 of guide sleeve rod and the actuating cam for, the same. when valve of engineis on its seat, and 10 Another object of the present invention slidably mounted within the cylinder 5 is 160 is the provision of a valve litter of the above a" plunger 10 provided with a longitudinal type which is maintained in an adjusted bore 11 opening into an enlarged chamber position at all times, through the-action of a at the lower end, a The major portion of suitable fluid which' will automatically take the enlarged chamber 12 is :formed within '15 up any looseness in the m'echanism,so that a reduced part 13, supporting-fa transverse 65 the usual valve will be operated at the pin 14 which retains the ball valve 15 in proper time through engagement of the place. p I

lifter with the usual cam for actuating the Theupper end of the bore 11 opens into valve, thus eliminating the necessity of a transverse borel6, while the lower end adjusting the valve lifters: at various opens into the. chamber 12. Normally enintervals. gagingthe upper'end of the plunger 10 is p A further object of the present invention the lower end of the valve stem or push rod is the provision of a self-adjusting valve 17, which is connected to the usual poppet lifter, which is supplied with a suitable valve, and engaging the lower end of $116- 2 fluid from the regular lubricating lines of plunger 10, is a coil spring 18 which emthe engine, so that the supply of fluid to the braces the reduced part 13, as shown, while valve lifter will be maintained constant at h l w r nd Of th c il spring rests on all times to assure the proper working of the the l s d b m 2 0f the cylinder 5- A lifter. chamber 23 is thus formed between the lower 30 With th ab v and ther objects'i iew end 24 of plunger 10 and closed bottom 22 the invention consists in the novel features of cylinder 5. of construction, the combination and ar- The guide sleeve 1 c n be supported in. the rangement of parts hereinafter more fully Crank Case or on cylinder block of engine set forth, pointed out in the claim and in any suitable manner and communicating 35 shown in the accompanying drawing wherewith the interior of the receptacle 3 is a conin: duit 19, which is preferably connected up Figure 1 is a vertical sectional view With the oil pump of the engine, so that this through a valve lifter constructed in accordreceptable-will be normally filled with fluid. ance with our invention, with adjacent parts In the operationof the device, after the 40 thereof in elevation; and, valve tappet has been assembled and the Figur 2 i a transverse ection on the motor of the vehicle has started .to rotate line 22 of Figure 1. the camshaft, the high'point 20 of the Referring to the drawing, 1 indicates a cam8 will engage the head 6 of the cylinder guide sleeve of the valve lifter, provided 5, raising the cylinder and compressing 45 with a reduced end portion 2 adapted to be spring 18 therein. -At thesame time, the 5 fitted within a suitable opening in the top airin the chamber 23 in the lower end of of the crank case. The upper end of the cylinder 5 will be forced-out through the guide is provided with an upstanding tubuclearance. between the plunger 10 and the lar portion 3 which forms a receptacle for cylinder 5. A 5o fluid as indicated at 4. As the cam continues to rotate, the-closed bottom 22 of the cylinder 5 engages the lower end 24 of the plunger 10 which in turn engages the lower end of valve stem or push rod 17, as shown in-Figure 1, this amount of movement opening valve of engme.

As the cam continues to rotate, moving the high point 20 away from the head 6 of cylinder 5,'the valve of the engine will return to its seat, due to the tension of the usual poppet valve spring, and the tension of the spring 18 will hold the plunger 1O stationary in contact with the lower end ofthe valve stem or push rod '17, forcing the cylinder 5 downwardly with the head 6, following the cam to its lowest point. This movement will create a partial vacuum in the chamber 23 of the cylinder 5, whereby the oil or other fluid in the receptacle 8will be forced into this chamber, through atmospheric pressure, the fluid entering the transverse bore 16 of the plunger 10, passing downwardly through the bore 11 and the enlarged chamber 12 and into the chamber 23 of the cylinder 5.

Previous to the above operation, it will be apparent that the receptacle 3 has been filled with oil when assembled, and the oil in this receptacle is maintained at a constant level by connecting the conduit 19 with the usual oil pumps of an engine. After the head has reached the low point of the cam,

the chamber in the bottom of the cylinder 5 will be filled with a non-compressible fluid, and as the high point of the cam again engages the head 6, the cylinder 5 and the plunger 10 will be raised as a unit, due to the fact that the ball valve 15 will automatically engage the seat 15 to prevent any escape of the oil up through the bore 11.

If any clearance, or slack, in the mechanism begins, due to'a slight leakage of oil from the chamber in the lower end of the cylinder 5 between the plunger and the cylinder, the device will readily adjust itself to its proper length to open and close the valve of the engine at the proper time, by

In the accompanying drawing, We have illustrated a single valve mechanism. However, these devices ma be used as a single unit, or a group assem ly.

It will be apparent from the foregoing that we have provided a very simple and inexpensive valve lifter wherein the device is self-adjusting at all times and the leakage takes care of any expansion of parts due to heat, and assures the positive opening and closing of the valves at the proper time. The device is very simple in construction, comprising few parts and can be manufactured and placedon the market at a very low cost.

We claim:

In a device of the guide having an oil reservoir on the upper end thereof, a cylinder slidably mounted in the guidehaving its lower end provided with a head and its upper end open and extendin into-the oil reservoir, a cam for engagingsaidhead and operatlng said cylinder,

a plunger slidably mounted in the cylinder having a longitudinal bore and a chamber opening out of its lower end and communicating with the bore, said'plunger also having lateralports adapted to] extend into the oil reservoir at certain times", the chamber defining a. valve seat at its upper end, a valve in the chamber, the lower end of the plunger beingreduced to define a shoulder, and an expansion coil spring fitted around the reduced portion of the plunger and confined between the shoulder and the head of the cylinder. 7

In testimony that we claim the foregoing we have hereunto set our hands at Madison, in the county of Dane and State of VVisconsin.

AMEL L. PEARSON. JACOB J.- GERI-IARDT.

taking in the proper amount of oil at each 3 due to heat, as oil in the chamber 23 at the lower end of cylinder 5 will not be replenished until proper action between the plunger and cylinder occurs. Any surplus oil discharged into the receptacle 3 will overflow into the crank case, lubricating the cam shaft, the cams and other parts adjacent thereto.

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