US2991065A

US2991065A - Tandem rocker mount

Info

Publication number: US2991065A
Application number: US3860A
Authority: US
Inventors: Robert A Jewell; Johnny T Watters
Original assignee: Individual
Current assignee: Individual
Priority date: 1960-01-21
Filing date: 1960-01-21
Publication date: 1961-07-04
Anticipated expiration: 1978-07-04

Description

July 4, 1961 R. A. JEWELL ET AL TANDEM ROCKER MOUNT Filed Jan. 21, 1960 INVENTORS JkfiiAJW/l ATTORNEYS United States Patent j 2,991,065 r TANDEM ROCKER MOUNT Robert A. Jewell and Johnny T, Watters, both of P.(). Box 1007, Savannah, Ga. r Filed Jan. 21,1960, Ser. No. 3,860 6JClaims. (Cl. 267-19) This invention relatesto tandem wheel assemblies, and

particularly to the equalizing rockers of such assemblies and a novel mount therefor.

As is well known, it is common practice-to providean equalizing rocker between adjacent ends of a pair of springs in a conventional tandern wheel mount, so that shoclgs to one axle will be transmitted through its spring to the rocker and from the ro c ker to the other,springof the mount to transfer part of the shock to the other axle so as to equalize the shock between the axles and: permit one axle to compensate for movement of the other. In conventional practice, the rocker is freely pivoted in a hanger which is secured to the vehicle frame. :Although,

ture wherein the rocker is mounted-so as to absorb, shocks and, to some extent, cushion load transference from one axle to. the other. i a

Another object istoprovide a. rocker mount which will bias the rocker to its nonnahinoperative position and provide torque resistance to movement from that position.

i A further object is the provision of stnlcture. of this nature which produces unique interaction between the pivot pin and rockerand in which, a resilient interconnection between thetwo. is made byinsertion of the pin in the rocker. I

Still another object is to provide a resilient interconnection as set' out above in which, during assembly, the resilient member of-the assembly will be automatically pre-stressed to the properdegree.

Yet another object is to providearocker mount of the type described above which will substantiallyel iminate noise and rattle during operation ofrocker.

Other objects of the invention will become apparent from the following description of one practical embodiment thereof, when taken in conjunction with the drawings which accompany, and form part of, this specification.

In the drawings:

FIGURE 1 is a side elevation of a portion of a vehicle frame, showing the rocker arm and its mounting bracket and associated structure;

FIGURE 2 is a vertical, transverse section through the structure shown in FIGURE 1, and is taken on the line 2-2 of FIGURE 1;

FIGURE 3 is a horizontal section taken on the line 33 of FIGURE 2; and

FIGURE 4 is a vertical section taken on the line 44 of FIGURE 2.

In general, the invention consists in a rocker arm provided with a resilient bushing and a pivot pin which is secured to the bushing and hold against rotative movement, whereby rocking movement of the rocker results in, and is resisted by, torque action of the bushing, and the bushing acts as a shock absorber for the rocker arm. The invention also concerns the novel arrangement of the parts and their assembly.

r t A more specific object is the provision of such strucg ice Referring to the drawings in detail, there is shown a portion of a bottom side rail, or frame member 1 of a vehicle, with a bracket 2 bolted, or otherwise secured, to the rail. The bracket has an upper web 3' which fits flush against the vehicle frame and is secured to it, and a bifurcated lower section 4providing transversely spaced, depending legs 5. The legs have, axially aligned aper tured bosses 6;to receive, a pivot pi n 7. The legs S are in the form of rearwardly curving horns and have at their tips another pair ofaxially aligned apertured bosses 8:

which receive-a pivot pin 9 to fasten one end of a radius Y rod 10, to the bracket. The opposite end of the rod will i be connected to the rear. axle of the vehicle, as is well known.

Anfequalizing rocker 11 is mounted on the pivot pin 7. The rocker has an opening 12 in its central section to receive the pivot pin. The rocker has arms 13 extending from thecentral portion, from which spaced flanges project inwardly to, define a channel 14 into which the endsof adjacent springs 15 are 'slidably mounted. I

In accordance with the present invention, the opening. 12 in the rocker arm is somewhat larger thanthe diameter of the pivot pin. This permits the use of a bushing .16 in the opening 12, which serves as a shock-absorbing shield between the pivot pin and rocker and, at; the same,

ly oversize for the hole 12 in the rocker so that it must.

be compressed slightly to fit into the hole, causing the. areuate sections. of the ring to move closer toward one another.

Pivot pin 7 has a diameter. approximating that of the :H inside of the metal ring. before the rubbersleeve is compressed by pressing into the opening. of the. rocker. arm.

It is necessary, therefore, to provide a tapcredleading end, 21 on thepin to enter between the ring sections. to;

move them apart to the; diameter of the body. of the pin.

The pin is provided with diametrically opposed grooves 22 .to receive the guide flanges 2Q of the ring. sections. As the sections were pressed together by insertion of the.

bushing in the rocker arm, the pairs of flanges2li fwill. be relatively closely spaced and will enter freely the grooves 22 on the tapered area of the pin, as the pin is inserted. As the pin spreads the ring sections, the flanges 20 will come into contact with the side walls of the grooves and the sections will be tightly gripped about the curved walls of the pin. The spreading of the metal ring will further compress the rubber sleeve so that it will be firmly compacted, and its outer surface will be tightly bound frictionally to the inner wall of the rocker arm opening 12. Thus, the outer surface of the bushing will be held to the rocker arm and the metal ring will be fixed to the pivot pin, so that no rocking movement of the rocker relative to the pin can take place unless the rubber sleeve is tortionally twisted. This means that the torque of the rubber sleeve will resist all rotative movement of the rocker. It is to be noted that the amount of ultimate compression of the resilient bushing, and thereby the degree of pre-stressing of the bushing, may be predetermined by the relative diameters of the rocker arm opening 12, the inner and outer diameters of the bushing 16, and the diameter of the pin 7. Thus, the amount of compression of the bushing and the degree of pre-stressing can be accurately predetermined, and the insertion of the Batentecl July 4, 1961 pin 7 in the bushing will compress the resilient member thedetermined amount and thus automatically accomplish the desired prestressing without need for additional adjustment. t

In order to hold the pivot pin stationary, the bosses 6 of the bracket 2 are provided with keys 23 which project into the pivot pin openings and'which are positioned to fit into the grooves 22 of the pin. As the keys are provided at both bosses, the pin will be held at both ends and completely rigid and stationary. The pin is held, against endwise movement by cap plates 24 which are bolted to the bosses 6 to overlie the pivot pin ends. The pin is beveled at its bottom at each end, as at 25, and the end plates have wedges 26 which enter the openings in the bosses, engage the beveled surfaces 25 of the pivot pin, and lift the pin to bring the bottom sides of the grooves into tight engagement with the keys 23. This will compensate for play and hold the pin immovable. All noise, rattle and movement will be removed by this arrangement.

It will be seen from the above that the rocker will be mounted upon an immovable pin with a bushing of rub-- ber interposed between the pin and rocker. The bushing is frictionally held against rotative movement relative to the rocker, and positively held by the flanges of the split ring to the pin. All rocking movement of the rocker arm will be resisted by the rubber sleeve, and shocks to the rocker will be absorbed by the rubber sleeve. This arrangement will greatly stabilize the rocker arm action, reduce shocks, and substantially eliminate rocker arm noise.

While in the above one practical embodiment of the invention has been disclosed, it will be understood that the details of structure shown and described are merely for purposes of illustration, and the invention may take other forms within the scope of the appended claims.

What is claimed is:

'1. A mounting for a tandem rocker arm comprising, a mounting bracket having a pair of spaced legs provided with openings in axial alignment, keys in the openings with the keys of the openings of two legs aligned with one another, a rocker arm having an opening intermediate its ends, a rubber sleeve frictionally held within the opening in the rocker arm, a split ring fixed to the inner surface of the rubber sleeve and havingflanges at the edges of the split ring extending inwardly toward the center of the ring, a pin extending through the openings in the bracket legs and rocker arm pivotally mounting the-rocker arm between the bracket legs, said pin having a groove lengthwise of its surface into which the keys of the bracket legs seat to hold the pin against rotation and into which the flanges of the split ring seat to lock the split ring to the 2. A mounting for a tandem rocker arm as claimed in claim 1' wherein the rubber bushing has an outer diameter larger than the opening in the rocker arm so that the bushing is compressed within the rocker arm opening for tight frictional surface engagement between the bushing and the rocker arm, and the pin has a tapered end for insertion within the split ring to spread the ring and compress the rubber bushing.

3. A mounting for a tandem rocker arm as claimed in claim 2 wherein cap plates are secured to the bracket legs overlying the pin ends to prevent endwise movement of the pin, the pins are beveled at opposite ends,

, and the caps carry wedges fitting between the beveled ends of the pin and the inner surfaces of the bracket openings to bind the pins in the bracket leg openings.

4. A mounting for a tandem.- rocker arm as claimed in claim 3 wherein the keys in each bracket leg opening 7 are oppositely opposed, the pin has a second groove diametrically opposite the first, and the split ring is in two in claim 4 wherein the split ring sections are bonded to the rubber bushing.

' silient sleeve and a split ring bonded to the inner surface of the sleeve, means carried by'the split ring engaging the pin to lock the split ring to the pin, and cap plates secured to the brackets overlying the openings inthe brackets to prevent endwise movement of the pin, the pin having beveled ends and the cap plates carrying wedges fitting between the beveled ends of the pin and the inner surfaces of the bracket openings to lift the pin and bind it in the bracket openings.

I References Cited in the file of this patent UNITED STATES PATENTS 1,961,536 Thiry June 5, 1934 2,240,709 Mead May 6, 1941 2,749,141 Mal-tin June 5, 1956 2,900,197 Hutchens Aug. 18, 1959 FOREIGN PATENTS 140,267 Australia Feb. 16, 1951