Patent Description:
Metal cans are often produced as two-piece cans which comprise a cylindrical can body with an integral bottom wall and a can top. The can is typically made from aluminum. Typically, curved sections are formed at the bottom and top of the can to increase its structural integrity.

The beverage can fabrication industry utilizes a variety of aluminum bending and shaping machines that have very demanding requirements. A typical beverage can fabrication plant runs <NUM> hours per day and can produce upwards to <NUM> cans per minute across <NUM> to <NUM> several fabrication lines. A can making machine, sometimes referred to as a necker, forms the curved sections of the can by progressively squeezing, i.e. necking, the can body between opposing ram bodies which squeeze the can. The ram typically includes one or more cam followers extending therefrom. The cam followers ride on a cam that is mounted on a cylinder. As the ram rotates about the cylinder, the cam follower rides on the cam, which is configured to move the ram back and forth.

One of the operations in the line is called the necking station. These machines consist of rotating high-speed turrets that feed the can in and gradually form a neck and a flange at the top of the can that will eventually mate with the lid after filling. Stud mounted cam followers are a vital part of the mechanism in the necking station allowing the cans to enter, get worked, and exit.

Automated greasing systems are required to keep the cam followers lubricated and able to provide sufficient service life. Machine design complexity and maintenance is greatly reduced if these cam followers are designed to be maintenance free.

<CIT>) discloses an air-conditioning compressor provided with a casing, with a shaft able to rotate about an axis, and with a torque-transmitting device comprising a pulley, a rolling bearing positioned inside the pulley and comprising an inner ring, an outer ring and at least one row of rolling elements, and a torque-transmitting member equipped with an external part angularly connected to the pulley, with an internal part fixed to the shaft and with at least two arms connecting the external part and the internal part. Empty spaces are formed between the arms, the bore of the inner ring having a radius greater than the distance between the axis of rotation and an internal end of the empty spaces so as to allow the insertion of a crimping tool. Local plastic deformations of the casing interfere with a transverse face of the inner ring, the local plastic deformations being positioned in axial alignment with the said empty spaces in at least one relative angular position between the torque-transmitting member and the inner ring.

<CIT>) <FIG> discloses a cam follower assembly <NUM> including two rows of rollers <NUM> and <NUM> surrounding and in rolling engagement with exterior bearing surfaces <NUM> and <NUM> of a stud or shaft <NUM>. The stud <NUM> has an outwardly protruding shoulder <NUM> that is integral with the stud <NUM>. A first outer ring <NUM> surrounds the first row of rollers <NUM>; and a second outer ring <NUM> surrounds the second row of rollers <NUM>. A first end plate <NUM> is swaged <NUM> onto the stud <NUM> at a distal end 130D of the stud <NUM>. The first end plate <NUM> and the shoulder <NUM> axially retain the first row of rollers <NUM> therebetween.

<CIT> discloses a cam follower for a ram of a metal can necker machine. The cam follower has an outer ring and an inner ring coaxially disposed in the outer ring. A plurality of rolling elements is disposed in an annular cavity between the outer ring and the inner ring. The plurality of rolling elements is disposed between a first seal and a second seal. A shaft is received in a bore in the inner ring and is fixed relative thereto about the shaft axis. The outer ring is received in a tire. The tire has a thickness and a crown radius.

Therefore, there is a need for improved maintenance free cam followers that are creep free and that also include optimized ball bearing internal clearance reduction for maximum service life.

Disclosed herein is an axial retainment system for a shaft. The axial retainment system includes a cylindrical body or shaft extending from an outboard end or first axial end to an inboard end or second axial end thereof, and a swaged ridge extending radially outward from the shaft proximate the first axial end. The swaged ridge has an outboard axial surface facing toward the first axial end and extending radially outward and terminating at a radially outward facing circumferential surface. The swaged ridge has an inboard axial surface facing toward the second axial end and extending radially outward from the shaft and terminating at the radially outward facing circumferential surface.

In one example, the outboard axial surface is recessed axially inward from the first axial end.

In one example, the outboard axial surface is substantially flat.

In one example, the first axial end of the shaft includes a torque transmission aperture extending axially inward therefrom. The torque transmission aperture has a radially inward facing engagement surface. The outboard axial surface is spaced apart from the engagement surface by a neutral zone that extends a predetermined radial distance from the engagement surface to the radially innermost portion of the outboard axial surface, to prevent deformation of the engagement surface when forming the swaged ridge.

In one example, the inboard axial surface is swaged against, conforms in shape to, and is compressed against a component to be axially retained on the shaft.

In one example, the inboard axial surface is substantially flat.

In one example, the inboard axial surface is arcuate.

In one example, the inboard axial surface is beveled.

In one example, the shaft has an outboard diameter as measured proximate the first axial end, and the swaged ridge has a swage diameter as measured at the radially outward facing circumferential surface. The swage diameter is greater than the outboard diameter.

In one example, the swage diameter is about <NUM>% to about <NUM>% greater than the outboard diameter.

In one example, the system further includes a circumferential flange extending radially outward from the shaft between the swaged ridge and the second axial end. The flange has a shoulder extending axially outward toward the first axial end on an outboard axial surface of the flange.

In one example, the system further includes a component being axially retained and compressed between the shoulder of the flange and the inboard axial surface of the swaged ridge.

In one example, the component includes at least one ball bearing. The at least one ball bearing has a plurality of rolling elements disposed between an inner ring and an outer ring. The inner ring axially abuts the inboard axial surface of the swaged ridge and the shoulder of the flange.

The invention disclosed herein relates to a cam follower according to claim <NUM>, that includes an outer ring that has an outer ring bearing surface and an exterior surface, and an inner ring that is coaxially disposed in the outer ring. The inner ring has an inner ring bearing surface and a bore extending therethrough. A plurality of rolling elements is disposed in an annular cavity between the outer ring bearing surface and the inner ring bearing surface. The plurality of rolling elements is in rolling engagement with the outer ring bearing surface and the inner ring bearing surface such that the outer ring is rotatable relative to the inner ring about a shaft axis. A shaft is received in the bore in the inner ring so that the shaft is fixed relative to the inner ring about the longitudinal axis of the shaft. The shaft has a first end and a second end. The shaft has a circumferential flange extending radially outward from the shaft and located between the first axial end and the second axial end. The shaft has a swaged ridge formed at the first axial end extending radially outward and extending circumferentially around the shaft. The inner ring is axially retained on the shaft by the swaged ridge and the flange.

In one embodiment, the outer ring is received in a tire. The tire has a thickness and a crown radius. The crown radius has an apex. The inner ring and the outer ring are axially centered with respect to the apex. The composition of the tire includes at least one of a metallic material, a plastic material, and a non-metallic material. The tire has a groove formed therein. The groove extends radially outward and extends circumferentially therearound. The outer ring is axially retained by a clip disposed at a depth in the groove.

In one embodiment, the swaged ridge impacts an axial compressive force on the inner ring to retain and compress the inner ring between the swaged ridge and the flange.

In one embodiment, the ratio of the depth to the tire thickness is between <NUM> and <NUM>.

In one embodiment, a first distance is defined between an exterior surface of the outer ring and the longitudinal axis of the shaft, and a second distance is defined between the longitudinal axis of the shaft and an interior surface of the tire. A ratio of the first distance to the second distance is between <NUM> and <NUM>.

In one embodiment, the plurality of rolling elements is a plurality of spherical balls.

In one embodiment, the cam follower has a duty cycle and a bearing load capacity is selected based on the duty cycle.

In one embodiment, the swaged ridge is formed by swaging the first axial end of the shaft with a swage die. The swage die includes a body having a first end configured to be mounted to a pressing device and a second end opposite the first end. The second end has a cylindrical extension extending from the second end away from the first end. The cylindrical extension has an end surface with a cylindrical punch cavity therein configured to engage and swage the first axial end of the shaft.

In one embodiment, the swaged ridge has a first axial surface facing toward the first end of the shaft and extending radially outward from the shaft and terminating at a radially outward facing circumferential surface. The swaged ridge has a second axial surface facing toward the second end of the shaft and extending radially outward from the shaft and terminating at the radially outward facing circumferential surface.

In one embodiment, the first axial surface of the swaged ridge is recessed axially inward from the first end of the shaft.

In one embodiment, the first axial surface of the swaged ridge is substantially flat.

In one embodiment, the first axial end of the shaft includes a torque transmission aperture extending axially inward therefrom. The torque transmission aperture has a radially inward facing engagement surface. The first axial surface of the swaged ridge is spaced apart from the engagement surface by a neutral zone that extends a predetermined radial distance from the engagement surface to the radially innermost portion of the first axial surface, to prevent deformation of the engagement surface when forming the swaged ridge.

In one embodiment, the second axial surface of the shaft is swaged against, conforms in shape to, and is compressed against the inner ring.

In one embodiment, the second axial surface is substantially flat.

In one embodiment, the second axial surface is arcuate.

In one embodiment, the second axial surface is beveled.

In one embodiment, the circumferential flange has a shoulder extending axially outward toward the first end of the shaft on a first axial surface of the flange. The inner ring is axially retained and compressed between the shoulder of the flange and the second axial surface of the swaged ridge.

There is also disclosed herein a cam follower that includes a shaft extending from a first axial end to a second axial end, a tire defining an interior area, a first ball bearing, and a second ball bearing. The shaft has a swaged ridge proximate to the first axial end, and a shoulder formed on the shaft between the swaged ridge and the second axial end. The tire has a flange extending radially inward from one axial end of the tire proximate the first axial end of the shaft, and an axial retainment feature at a second axial end of the tire. The first ball bearing has a first plurality of rolling elements disposed between a first inner ring and a first outer ring. The second ball bearing has a second plurality of rolling elements disposed between a second inner ring and a second outer ring. The first outer ring and the second outer ring extending at least partially into the interior area of the tire. The first inner ring axially abuts the second inner ring and the swaged ridge. The second inner ring axially abuts the shoulder and the first inner ring. The first outer ring axially abuts the second outer ring and the flange. The second outer ring axially abuts the first outer ring and the axial retainment system. The swaged ridge axially retains the first inner ring and the second inner ring on the shaft between the swaged ridge and the shoulder.

In one embodiment, the swaged ridge imparts an axial compressive force on the first inner ring and the second inner ring to retain and compress the first inner ring and the second inner ring between the swaged ridge and the shoulder.

In one embodiment, the cam follower further includes a first seal extending radially between the first inner ring and the first outer ring, a second seal extending between the first inner ring and the first outer ring, a third seal extending between the second inner ring and the second outer ring, and a fourth seal extending between the second inner ring and the second outer ring proximate to the axial retainment system. The second seal and the first seal sealing a first lubricant therebetween and the third seal and the fourth seal sealing a second lubricant therebetween.

In one embodiment, the flange extends radially inward from the first axial end of the tire a first radial distance, and the axial retainment feature includes an angled abutment shoulder extending radially inward from the second axial end of the tire a second radial distance. The second radial distance is less than the first radial distance.

In one embodiment, the angled abutment shoulder includes an outboard sloped abutment surface extending radially and axially inward from an interior surface of the tire to a radially inward facing surface of the angled abutment shoulder, and an inboard sloped relief surface extending radially inward and axially outward from the second axial end of the tire to the radially inward facing surface of the angled abutment shoulder.

In one embodiment, the axial retainment system includes a groove extending radially outward at the second axial end of the tire.

In one embodiment, a clip is disposed at a depth in the groove. The tire has a thickness and a crown radius. The crown radius has an apex. The first inner ring and the second inner ring are axially centered with respect to the apex. The composition of the tire includes at least one of a metallic material, a plastic material, a non-metallic material, and combinations thereof.

In one embodiment, a ratio of the depth of the groove to the tire thickness is between <NUM> and <NUM>.

In one embodiment, a ratio of the tire thickness to a pitch radius of at least one of the bearings is between <NUM> and <NUM>.

In one embodiment, a first distance is defined between an exterior surface of the first outer ring and the shaft axis, and a second distance is defined between the shaft axis and an interior surface of the tire. The ratio of the first distance to the second distance is between <NUM> and <NUM>.

In one embodiment, the shaft includes a hollow portion.

In one embodiment, the first end of the shaft includes a torque transmission aperture extending axially inward therefrom. The torque transmission aperture has a radially inward facing engagement surface. The first axial surface of the swaged ridge is spaced apart from the engagement surface by a neutral zone that extends a predetermined radial distance from the engagement surface to the radially innermost portion of the first axial surface, to prevent deformation of the engagement surface when forming the swaged ridge.

In one embodiment, the cam follower includes a first cam follower segment and a second cam follower segment.

In one embodiment, the first cam follower segment has a first duty cycle and a first bearing load capacity being selected based on the first duty cycle.

In one embodiment, the second cam follower segment has a second duty cycle and a second bearing load capacity being selected based on the second duty cycle.

There is further disclosed herein a method of assembling a cam follower according to claim <NUM>. The method includes the steps of: providing a shaft extending from a first axial end to a second axial end thereof, the shaft having a circumferential shoulder extending radially outward from the shaft and being located between the first axial end and the second axial end; providing at least one bearing, the at least one bearing having an inner ring defining a bore, an outer ring coaxially disposed on the inner ring, and a plurality of rolling elements disposed between the inner ring and the outer ring; providing a swage die comprising a body having a first end configured to be mounted to a pressing device and a second end opposite the first end, the second end having a cylindrical extension extending from the second end away from the first end, the cylindrical extension having an end surface with a cylindrical punch cavity therein; inserting the first axial end of the shaft through the bore of the at least one bearing; positioning the at least one bearing on the shaft such that a first axial end of the inner ring abuts the circumferential shoulder of the shaft; securing the shaft in a fixture with the first axial end extending outwardly from the fixture; placing the punch cavity of the swage die on the first axial end of the shaft; pressing the swage die against the first axial end of the shaft; and swaging a swaged ridge on the shaft with the swage die, the swaged ridge extending radially outward from the shaft at the first axial end of the shaft, the swaged ridge having a first axial surface facing toward the first axial end of the shaft and extending radially outward and terminating at a radially outward facing circumferential surface, the swaged ridge having a second axial surface facing toward the shoulder of the shaft and extending radially outward and terminating at the radially outward facing circumferential surface, the second axial surface of the swaged ridge conforms in shape to and compresses against a second axial end of the inner ring. The swaged ridge axially retains the inner ring on the shaft between the swaged ridge and the shoulder.

In one embodiment, the method further includes the steps of: providing a tire, the tire having a flange extending radially inward from a first axial end of the tire and a groove extending radially outward at a second axial end of the tire; providing a clip; securing the tire to the outer ring of the at least one bearing such that a first axial end of the outer ring abuts the flange; and inserting the clip into the groove of the tire such that a second axial end of the outer ring abuts the clip.

In one embodiment, the method further includes the steps of: providing a tire, the tire having a flange extending radially inward from a first axial end of the tire and an angled abutment shoulder extending radially inward from a second axial end of the tire; and securing the tire to the outer ring of the at least one bearing such that a first axial end of the outer ring abuts the flange and a second axial end of the outer ring abuts the angled abutment shoulder. The angled abutment shoulder includes an outboard sloped abutment surface extending radially and axially inward from an interior surface of the tire to a radially inward facing surface of the angled abutment shoulder, and an inboard sloped relief surface extending radially inward and axially outward from the second axial end of the tire to the radially inward facing surface of the angled abutment shoulder.

In one embodiment, the method further includes performing a visual inspection of the swaged ridge to determine that the swaged ridge has a swage diameter as measured at the radially outward facing circumferential surface. The swage diameter is about <NUM>% to about <NUM>% greater than an outboard diameter of the shaft as measured at the at least one bearing.

There is also disclosed herein a method of visually inspecting a cam follower. The method includes the steps of: providing a shaft extending from a first axial end to a second axial end thereof, the shaft having a swaged ridge extending radially and circumferentially outward from the shaft and being located proximate the first axial end, the shaft having a bearing positioned thereon such that a first axial end of the bearing abuts the swaged ridge, the swaged ridge having a first color and the bearing having a second contrasting color; providing a visual inspection system configured to scan a face of an object, differentiate between at least two contrasting colors of at least two adjacent surfaces of the object, and measure a distance along the face of the object; scanning the first axial end of the shaft using the visual inspection system; differentiating between the first color of the swaged ridge and the second contrasting color of the bearing; measuring a swage diameter D8 of the swaged ridge at a radially outward facing circumferential surface thereof.

In one embodiment, the method further includes confirming that the swage diameter D8 is about <NUM>% to about <NUM>% greater than an outboard diameter D4 of the shaft as measured at the bearing.

In one embodiment, the first color of the swaged ridge is darker relative to the second contrasting color of the bearing.

There is also disclosed herein a cam follower that includes an outer ring that has an outer ring bearing surface and an exterior surface; and an inner ring that is coaxially disposed in the outer ring. The inner ring has an inner ring bearing surface and a bore extending therethrough. A group of rolling elements is disposed in an annular cavity formed between the outer ring bearing surface and the inner ring bearing surface. The group of rolling elements is in rolling engagement with the outer ring bearing surface and the inner ring bearing surface such that the outer ring is rotatable relative to the inner ring about a shaft axis. The group of rolling elements have a pitch radius defined by a distance between a longitudinal axis of the shaft and a rolling element axis. A shaft is received in the bore in the inner ring so that the shaft is fixed relative to the inner ring about the longitudinal axis of the shaft. The shaft has a first groove formed therein. The first groove extends radially inward and circumferentially around the shaft. The group of rolling elements are disposed between a first seal and a second seal which seal a lubricant therebetween. The inner ring is axially retained by a first clip that is disposed at a depth in the first groove. The outer ring is received in a tire which has a thickness and a crown radius. The crown radius has an apex. The inner ring and the outer ring are axially centered with respect to the apex. The composition of the tire includes a metallic material, a plastic material, and/or a non-metallic material. The tire has a second groove formed therein, extending radially outward and extending circumferentially therearound. The outer ring is axially retained by a second clip that is disposed at the depth in the second groove.

In one embodiment, a ratio of the depth to the tire thickness is between <NUM> and <NUM>.

In one embodiment, a ratio of the tire thickness to the pitch radius is between <NUM> and <NUM>.

In one embodiment, a first distance is defined between an exterior surface of the outer ring and the longitudinal axis of the shaft and a second distance is defined between the longitudinal axis of the shaft and an interior surface of the tire, wherein a ratio of the first distance to the second distance is between <NUM> and <NUM>.

In one embodiment, the group of rolling elements is a group of spherical balls.

In one embodiment, the cam follower has a duty cycle and a bearing load capacity being selected based on the duty cycle.

There is also disclosed herein a cam follower that includes a shaft that extends from a first axial end to a second axial end. The shaft has a first groove proximate to the first axial end and a shoulder formed in the shaft between the first groove and the second axial end. A first clip is radially engaged in the first groove. The cam follower includes a tire that has an interior area and a flange that extends extending radially inward from the tire at an axial end of the tire. A second groove extends radially outward at another axial end of the tire. The cam follower includes a first ball bearing and a second ball bearing. The first ball bearing has a first group of rolling elements disposed between a first inner ring and a first outer ring. The second ball bearing has a second group of rolling elements disposed between a second inner ring and a second outer ring. The first outer ring and the second outer ring extend partially into the interior area of the tire. The first inner ring axially abuts the second inner ring and the first clip. The second inner ring axially abuts the shoulder and the first inner ring. The first outer ring axially abuts the second outer ring and the flange. The second outer ring axially abuts the first outer ring and a second clip which is engaged in the second groove. The first clip axially retains the first inner ring and the second inner ring on the shaft between the first clip and the shoulder.

In one embodiment, a first seal extends between the first inner ring and the first outer ring; a second seal extends between the first inner ring and the first outer ring; a third seal extends between the second inner ring and the second outer ring; and a fourth seal extends between the second inner ring and the second outer ring, proximate to the first clip. The second seal and the first seal sealing a first lubricant therebetween and the third seal and the fourth seal sealing a second lubricant therebetween.

In one embodiment, the first clip is disposed at the depth in a first groove and a second clip is disposed at the depth in a second groove and the first tire has a thickness and a crown radius that has an apex. The first inner ring and the second inner ring are axially centered with respect to the apex. The composition of the tire includes a metallic material, a plastic material, a non-metallic material, and combinations thereof.

In one embodiment, a ratio of the tire thickness to a pitch radius of the bearing is between <NUM> and <NUM>.

In one embodiment, a first distance is defined between an exterior surface of the first outer ring <NUM> and the longitudinal axis of the shaft and a second distance is defined between the longitudinal axis of the shaft and an interior surface of the tire and a ratio of the first distance to the second distance is between <NUM> and <NUM>.

In one embodiment, the first cam follower segment has a first duty cycle and a bearing load capacity being selected based on the first duty cycle.

In one embodiment, the second cam follower segment has a second duty cycle and a bearing load capacity being selected based on the second duty cycle.

There is further disclosed herein a cam follower that includes a shaft that extends from a first axial shaft end to a second axial shaft end. The shaft has a first groove located proximate to the first axial shaft end. The shaft has a shoulder formed in (extending radially outward from) the shaft and located between the first groove and the second axial shaft end. A first clip is radially engaged in the first groove. The cam follower includes two cam follower segments, namely a first cam follower segment and a second cam follower segment. The first cam follower segment includes a first tire that defines a first interior area. The first cam follower segment has a first ball bearing and a second ball bearing, both being partially disposed in the first interior area of the first tire. The second cam follower segment includes a second tire that defines a second interior area. The second cam follower segment has a third ball bearing and a fourth ball bearing, both being partially disposed in the second interior area. The cam follower includes a spacer disposed on the shaft between the second ball bearing and the third ball bearing. The first cam follower segment and the second cam follower segment are axially retained on the shaft by the first clip, the spacer and the shoulder.

In one embodiment, the first tire includes: (i) a first flange extending radially inward from the first tire and located at a first axial tire end of the first tire; (ii) a second groove extending radially outward into the first tire and located at a second axial tire end of the first tire; and (iii) a second clip is engaged in the second groove. The second tire includes: (i) a second flange extending radially inward from the second tire and located at an third axial tire end of the second tire; (ii) a third groove extending radially outward into the second tire and located at a fourth axial tire end of the second tire; and (iii) a third clip engaged in the third groove.

In one embodiment, the first ball bearing has a first inner ring disposed in a first outer ring and has a first group of rolling elements disposed between the first inner ring and the first outer ring. The second ball bearing has a second inner ring disposed in a second outer ring and has a second group of rolling elements disposed between the second inner ring and the second outer ring. The first inner ring axially abuts the second inner ring and the first clip. The first outer ring axially abuts the second outer ring and the first flange. The second outer ring axially abuts the second clip. The third ball bearing has a third inner ring disposed in a third outer ring and has a third group of rolling elements disposed between the third inner ring and the third outer ring. The fourth ball bearing has a fourth inner ring disposed in a fourth outer ring and has a fourth group of rolling elements disposed between the fourth inner ring and the fourth outer ring. The third inner ring axially abuts the fourth inner ring. The fourth inner ring axially abuts the shoulder. The third outer ring axially abuts the second flange and the fourth outer ring. The fourth outer ring axially abuts the third outer ring. The spacer abuts the second inner ring and the third inner ring.

In one embodiment, the first group of rolling elements is disposed between a first seal and a second seal. The first seal and the second seal contain (i.e., seal) a first lubricant therebetween. The second group of rolling elements is disposed between a third seal and a fourth seal. The third seal and the fourth seal contain (i.e., seal) sealing a second lubricant therebetween. The third group of rolling elements is disposed between a fifth seal and a sixth seal. The fifth seal and the sixth seal contain (i.e., seal) a third lubricant therebetween. The fourth group of rolling elements is disposed between a seventh seal and an eighth seal. The seventh seal and the eighth seal contain (i.e., seal) a fourth lubricant therebetween.

In one embodiment, the first seal is fixed to the first outer ring, the third seal is fixed to the second outer ring, the fifth seal is fixed to the third outer ring, and the seventh seal is fixed to the fourth outer ring.

In one embodiment, the second seal is fixed to the first outer ring, the fourth seal is fixed to the second outer ring, the sixth seal is fixed to the third outer ring, and eighth seal is fixed to the fourth inner ring.

In one embodiment, the first inner ring, the second inner ring, the spacer, the third inner ring, and the fourth inner ring define an axial stackup.

The examples of <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, and <FIG> do not form part of the invention but represent background art that is useful for understanding the invention.

As shown in <FIG> and <FIG>, a cam follower <NUM> for a ram of a necker machine is shown and is generally designated by the reference numeral <NUM>. The cam follower <NUM> includes a first ball bearing <NUM> and a second ball bearing <NUM>. The first ball bearing <NUM> and the second ball bearing <NUM> are configured in a tandem configuration. That is, they are positioned axially side to side, coaxially with a first axis of rotation A. In the example shown, an inner ring <NUM> of the first ball bearing <NUM> and an inner ring <NUM> of the second ball bearing <NUM> are axially and radially fixed relative to each other about the first axis of rotation A.

The first ball bearing <NUM> includes a first outer ring <NUM> that has a first outer race <NUM> (also referred to as a bearing surface) and a first exterior surface <NUM>. The first ball bearing <NUM> further includes the first inner ring <NUM> which has a first inner race <NUM> (also referred to as a bearing surface). The first inner ring <NUM> is coaxially disposed in the first outer ring <NUM>. A first plurality of rolling elements <NUM> are disposed between the first outer race <NUM> and the first inner race <NUM>. The first plurality of rolling elements <NUM> are, for example, spherical balls. The first plurality of rolling elements balls <NUM> are in rolling engagement with the first outer race <NUM> and the first inner race <NUM> such that the first outer ring <NUM> is rotatable relative to the first inner ring <NUM> about the first axis of rotation A.

The first ball bearing <NUM> includes a second seal <NUM> extending radially between the first outer ring <NUM> and the first inner ring <NUM> on one side of the first plurality of rolling elements <NUM>. The first ball bearing <NUM> further includes a first seal <NUM> that extends radially between the first outer ring <NUM> and the first inner ring <NUM> such that the first plurality of rolling elements <NUM> is sealingly positioned between the first seal <NUM> and the second seal <NUM>. The first seal <NUM> and the second seal <NUM> are configured to retain a lubricant <NUM> inside an annular cavity <NUM> formed between the first outer race <NUM> and the first inner race <NUM> in which the first plurality of rolling elements <NUM> is disposed. The seals <NUM>, <NUM> are made of a molded nitrile rubber, however, as can be appreciated by a person having ordinary skill in the art and familiar with this disclosure, the seals <NUM>, <NUM>, also referred to as shields, can employ different materials in alternate examples.

The lubricant <NUM> is selected to be maintenance free and to function for the useful life of the cam follower <NUM>. In some examples, the lubricant <NUM> is a general-purpose wide temperature range grease having anti-oxidation and anti-wear properties.

In the example disclosed in <FIG>, the second ball bearing <NUM> is similar in configuration to the first ball bearing <NUM>. The second ball bearing <NUM> includes a second outer ring <NUM> that has a second outer race <NUM> (also referred to as a bearing surface) and a second exterior surface <NUM>. The second ball bearing <NUM> further includes a second inner ring <NUM> that has a second inner race <NUM> (also referred to as a bearing surface). The second inner ring <NUM> is coaxially disposed in the second outer ring <NUM>. A second plurality of rolling elements <NUM> are disposed between the second outer race <NUM> and the second inner race <NUM>. The second plurality of rolling elements <NUM> are, for example, spherical balls. The second plurality of rolling elements <NUM> are in rolling engagement with the second outer race <NUM> and the second inner race <NUM> such that the second outer ring <NUM> is rotatable relative to the second inner ring <NUM> about the first axis of rotation A.

The second ball bearing <NUM> includes a third seal <NUM> that extends radially between the second outer ring <NUM> and the second inner ring <NUM> on one side of the second plurality of rolling elements <NUM>. The second bearing <NUM> further includes a fourth seal <NUM> that extends radially between the second outer ring <NUM> and the second inner ring <NUM> such that the second plurality of rolling elements <NUM> are sealingly positioned between the third seal <NUM> and the fourth seal <NUM>. The seals <NUM>, <NUM> are configured to retain the lubricant <NUM> inside an annular cavity <NUM> formed between the second outer race <NUM> and the second inner race <NUM>. The second plurality of rolling elements <NUM> are disposed in the annular cavity <NUM>. The seals <NUM>, <NUM> are made of a molded nitrile rubber, however, as can be appreciated by a person having ordinary skill in the art and being familiar with this disclosure, the seals <NUM>, <NUM>, also referred to as shields, can employ different materials in alternate examples.

In reference to the example shown in <FIG>, <FIG>, <FIG>, <FIG>, and <FIG>, although the cam follower <NUM> is shown having a first ball bearing <NUM> and a second ball bearing <NUM>, the present invention is not limited in this regard and, as will be appreciated by a person of ordinary skill in the art, many different configurations may be employed. For example, the present invention is practiced using a cam follower having a single row of roller or ball bearings. Or, for example, in one example the present invention is practiced using a cam follower having a ball bearing wherein a single continuous outer ring defines a first outer race and a second outer race, and a single continuous inner ring defines a first inner raceway and a second inner raceway.

In the example shown in in <FIG>, <FIG>, <FIG>, <FIG>, and <FIG>, the outer ring <NUM>, the outer ring <NUM>, the inner ring <NUM> and/or the inner ring, <NUM> are manufactured from a <NUM> steel that is through hardened. The first plurality of rolling elements <NUM> and the second plurality of rolling elements <NUM> also are manufactured from a <NUM> steel. As shown in <FIG>, each of the first plurality of rolling elements <NUM> are separated by a cage <NUM>; and each of the second plurality of rolling elements <NUM> are separated by another cage <NUM>. The cages <NUM> are manufactured from a low carbon soft steel. It should be understood that the present invention is not limited to using the cage <NUM> to separate adjacent rolling elements <NUM> from one another and another cage <NUM> to separate adjacent rolling elements <NUM>, as different spacers, or no spacers, may be employed between the balls in the first plurality of rolling elements <NUM> and as different spacers, or no spacers, may be employed between the balls in the second plurality of rolling elements <NUM>. It should also be understood that the present invention is not limited to balls, as other types of rolling elements may be employed with the present invention, for example, needle rollers.

Although specific materials are disclosed herein, a person of ordinary skill in the art and familiar with this disclosure will understand that the present invention is not limited in this regard, and that other materials may be used with the present invention.

In reference to in <FIG>, <FIG>, <FIG>, <FIG>, and <FIG>, the first inner ring <NUM> has a first bore <NUM> extending therethrough, and the second inner ring <NUM> has a second bore <NUM> extending therethrough. A shaft <NUM> is received through the first bore <NUM> and the second bore <NUM>. In the example shown in <FIG>, the shaft <NUM> is press fit in the first bore <NUM> and the second bore <NUM> such that the first inner ring <NUM> and the second inner ring <NUM> are fixed relative to the shaft about the first axis of rotation A. The shaft <NUM>, also referred to as a stud, extends between a first axial end <NUM> and a second axial end <NUM>. The shaft <NUM> has a first groove 93A formed therein. The first groove 93A extends radially inward into the shaft <NUM> and circumferentially around the shaft <NUM> (e.g., continuously around). The first groove 93A is located proximate the first axial end <NUM> of the shaft <NUM>.

The first ball bearing <NUM> and the second ball bearing <NUM> axially abut one another and are received on the shaft <NUM> proximate to the first axial end <NUM>, thereof. The shaft <NUM> has a shoulder <NUM> projecting radially outward from the shaft <NUM>. The shoulder <NUM> is located between the first axial end <NUM> and the second axial end <NUM>. Once assembled, the second inner ring <NUM> abuts the shoulder <NUM> to inhibit axial movement of the ball bearings <NUM>, <NUM> relative to the shaft <NUM>. A first clip <NUM> is fixedly received in the groove 93A on the shaft <NUM>, such that the first inner ring <NUM> of first ball bearing <NUM> and the second inner ring <NUM> of the second ball bearing <NUM> are disposed and retained axially between the first clip <NUM> and the shoulder <NUM>. A tire <NUM> extends circumferentially around the first outer ring <NUM> and the second outer ring <NUM>. A second groove 93C is formed in tire <NUM>. The second groove 93C extends circumferentially around and radially outward into the tire <NUM>. The second groove 93C is located proximate an inner axial end of the second outer ring <NUM>. The tire <NUM> has a radially inward projecting flange <NUM> located proximate an outer axial end of the first outer ring <NUM> proximate to the first axial end <NUM> of the shaft <NUM>. A second clip 93B is seated in the second groove 93C to axially retain first outer ring <NUM> and the second outer ring <NUM> between the second clip and the flange <NUM> and to inhibit axial movement of the ball bearings <NUM>, <NUM> relative to the shaft <NUM>. The first clip <NUM> engages the inner ring <NUM> of the first ball bearing <NUM> to axially secure the first ball bearing <NUM> on the shaft <NUM> and second clip 93B engages the outer ring <NUM> of the second ball bearing <NUM> to axially secure the second ball bearing <NUM> to the tire <NUM>. The second inner ring <NUM> abuts the shoulder <NUM> of the shaft <NUM> such that the first inner ring <NUM> and the second inner ring <NUM> are fixed relative to one another and fixed relative to the A axis along the shaft <NUM>. The first ball bearing <NUM> and the second ball bearing <NUM> are located symmetrically on opposing sides of an apex R' of the cam follower crown radius R such that the first ball bearing <NUM> and the second ball bearing <NUM> axially abut one another under the apex R' to optimize load distribution. To accomplish this symmetry, the first clip <NUM> and the second clip 93B are secured about the shaft <NUM> such that first clip <NUM> and the second clip 93B are equidistant from the center axis B. This allows for equalization of load sharing by the first ball bearing <NUM> and the second ball bearing <NUM> for improved performance compared to prior art cam followers.

As shown in <FIG>, the shaft <NUM> includes a face <NUM> at the first axial end <NUM> perpendicular to the first axis of rotation A. The face <NUM> has a recessed hexagonal socket <NUM> configured to receive a hex wrench, or the like, for rotating the shaft <NUM> about the first axis of rotation A. The shaft <NUM> further includes a plurality of threads <NUM> on a radial outside surface 97A of the shaft <NUM>. In this way, the shaft <NUM> can be received in a bore (not shown) comprising a complementary thread pattern or can similarly be received in a nut or the like having a complementary thread pattern. The shaft also included a hollow portion <NUM>. This allows for weight reduction of shaft <NUM> for efficiency of operation, thus allowing additional mass of a tire <NUM>, as described herein.

The first ball bearing <NUM> and the second ball bearing <NUM> are received in the tire <NUM>. In some examples, the tire <NUM> is made from a metallic material. In one example, the tire is made from steel. In a particular example, the tire <NUM> is made from carburized steel and includes an optional black oxide coating for maximum wear resistance. It should be appreciated that in alternate examples different tire materials and different tire sizes are used for the tire <NUM>. Further, the cam follower <NUM> is versatile in that in some examples the tires <NUM> are interchangeable with, for example, tires made of other metallic materials and tires made from elastomers, polymers or combinations thereof. The tire <NUM> has an exterior surface <NUM>, which includes a crown radius R and an apex R'. The crown radius R is bowed about the center axis B, which is substantially perpendicular to axis A. The tire <NUM>, includes a flange <NUM>. Flange <NUM>, in cooperation with the clip 93B, axially secures the first outer ring <NUM> and the second outer ring <NUM> to the tire <NUM> such that the tire is axially fixed to the first ball bearing <NUM> and the second ball bearing <NUM>. As shown in <FIG>, tire <NUM> has a thickness T1. The exterior surface <NUM> of the tire <NUM> engages the cam (not shown) during operating of the necker.

A pitch radius PR is defined as the distance between the midpoint of any one of the first plurality of rolling elements <NUM> and the axis A as shown in <FIG>. The pitch radius PR is also defined as the distance between the midpoint of any one of the second plurality of rolling elements <NUM> and the axis A as shown in <FIG>. The ratio of the thickness T1 of the tire <NUM> to the pitch radius PR (i.e., T1 divided by PR) is between about <NUM> and about <NUM>. Further, the ratio of the depth D1 of the second groove 93C (that the second clip 93B is disposed in) to the thickness T1 of the tire <NUM> (i.e., D1 divided by T1) is between about <NUM> and about <NUM>. The depth D1 of the second groove 93C is sized to provide a sufficient thickness of material to withstand axial forces and to axially retain the first outer ring <NUM> and the second outer ring <NUM> at a fixed axial position on the shaft <NUM> while allowing the first outer ring <NUM> and the second outer ring <NUM> to rotate around the shaft <NUM>. The <NUM> and about <NUM> ratio of the depth D1 of the first groove 93C to the tire thickness T1 also allows for minimization of the weight of the (e.g. metallic) tire <NUM> while maintaining sufficient material thickness of the tire <NUM> to meet strength and wear requirements for the tire <NUM>.

In reference to <FIG> and <FIG>, an example of a ram assembly <NUM> for a necker machine (not shown) is shown. In such a can making necker machine, a cam follower rides on a rotating cam <NUM> with the rotational axis AC parallel to the surface of the cam <NUM>. The ram assembly <NUM> extends between a first axial end <NUM> and a second axial end <NUM>. The ram assembly <NUM> includes a fixed bushing <NUM> having a bore extending therethrough between the first axial end <NUM> and the second axial end <NUM>. A ram piston <NUM> extends through both ends of the bore of the fixed bushing <NUM>. Proximate to the second axial end of the ram <NUM>, two cam followers (similar to the cam follower <NUM> illustrated in <FIG>, <FIG> and described in detail herein) extend radially therefrom. Referring to <FIG>, the cam followers <NUM>, including a first roller <NUM> and a second roller <NUM>, ride on a surface of a cam <NUM>, with one roller <NUM>, <NUM> located on each side of the cam <NUM>, as the rollers rotate around the rotational axis of the cam AC. The ram <NUM> is moved back and forth along the axis AR by the attached rollers <NUM>, <NUM> in an accelerating and decelerating movement following a profile of the cam <NUM>. Considerable radial force (i.e., force along the cam radial axis RC) is developed on the rollers <NUM>, <NUM> during the can necking operation.

Selection of the spherical ball (e.g. <NUM>, <NUM>) geometry for optimum service life via computer modeling of the bearing design was performed utilizing the load duty cycle of the necker machine as input. Necker machines can run <NUM> hours a day, <NUM> days a week and can process from about <NUM> cans per minute to about <NUM> cans per minute. Due to the unique geometry and corresponding efficiency, the instant cam follower design accommodates higher outputs of up to about <NUM> cans per minute.

The geometry of the first ball bearing and the second ball bearing <NUM> is selected to yield maximum load capacity and to allow the end user to stipulate the outer diameter of the tire <NUM>, as previously discussed. Specifically, the geometry of the rolling elements <NUM>, <NUM>, the inner rings <NUM>, <NUM>, and the outer rings <NUM>, <NUM> are adjusted to minimize the internal clearance C1, C2 in the respective bearing <NUM>, <NUM> thereby optimizing load distribution and service life. <FIG> depicts an internal clearance C1, C2 between the spherical ball <NUM> and the inner race <NUM> or outer race <NUM> of the first bearing <NUM>. <FIG> is also representative of the first bearing <NUM>', the second bearing <NUM>', the third bearing <NUM>", and the fourth bearing <NUM>'' as discussed herein with regards to <FIG>. Press fitting the interior surface <NUM> of the tire <NUM> over the outer rings <NUM>, <NUM> adjusts the internal clearance C1, C2. Generally, ball bearings have an industry standard internal clearance or looseness, which is reduced by the interference press fit of the outer rings <NUM>, <NUM> into the tire <NUM>. By reducing this internal clearance C1, C2, more rolling elements <NUM>, <NUM> within each bearing <NUM>, <NUM> share the applied load, thereby increasing and optimizing the bearing life. In some examples, the internal clearance is between about <NUM> and <NUM>. The applied load per duty cycle is discussed below with regards to <FIG> and <FIG>. A distance R1 is defined by the distance from the exterior surface <NUM>, <NUM> of the outer ring <NUM>, <NUM> to the shaft axis A. A distance R2 is defined by the distance from shaft axis A to an interior surface <NUM> of the tire <NUM>. The ratio of R1 to R2 is adjusted to optimize the load distribution. By maintaining a R1:R2 ratio between about <NUM> and about <NUM>, improved load sharing and longer bearing life is realized.

<FIG> depicts a duty cycle load chart for a first cam follower <NUM> ("Roller <NUM>" in <FIG>). <FIG> depicts a second duty cycle for a second cam follower <NUM> ("Roller <NUM>" in <FIG>). Roller <NUM> pushes a ram and a can into the work zone while roller <NUM> reacts the work load and returns the ram. Each duty cycle represents one revolution of the cam. The load is shown in the ordinate while the % of cycle is shown in the abscissa. With regard to <FIG>, the peak load for roller <NUM> occurs at between about <NUM>% and <NUM>% of the duty cycle (i.e. between about <NUM> degrees and <NUM> degrees of the <NUM>-degree duty cycle). Likewise, referring to <FIG>, the peak load for roller <NUM> occurs at between about <NUM>% and <NUM>% of the duty cycle (i.e. between about <NUM> degrees and <NUM> degrees of the <NUM>-degree duty cycle).

The resulting duty cycle life results for two rollers (e.g. <NUM>, <NUM>; see <FIG>) are shown in <FIG>. Roller <NUM> (<NUM>) and roller <NUM> (<NUM>) each have one of a ball bearing pairs identified as <NUM> and <NUM>. The <NUM> bearings are standard size, whereas the <NUM> bearings are packed more tightly due to having smaller diameters. Thus, load sharing is improved and the life tests demonstrate significantly improved results. Unfactored life, factored life and full factored life are shown in hours. Unfactored life is the most conservative prediction (no lubrication or special materials), factored life includes vacuum degassed steel and less conservative regarding predicted life, whereas fully factored prediction includes the effects of lubrication and steel properties, a more realistic and less conservative prediction. As shown, the fully factored life prediction for roller <NUM> improved from <NUM>,<NUM> hours for bearing pair <NUM> to <NUM>,<NUM> hours for bearing pair <NUM>. Likewise, an improvement from <NUM>,<NUM> hours (bearing pair <NUM>) to <NUM>,<NUM> hours (bearing pair <NUM>) was demonstrated for roller <NUM>. Thus, a significant and unexpected improvement in bearing life expectancy for a maintenance free cam follower has been demonstrated herein.

An alternate example includes two independently rotatable cam follower segments, for example first cam follower segment 10A' and second cam follower segment 10B', as depicted in <FIG>. The first cam follower segment 10A' and the second cam follower segment 10B' are mounted on a shaft <NUM>' that extends from a first axial shaft end <NUM>' to a second axial shaft end <NUM>'. The shaft <NUM>' has a first groove 93A' proximate to the first axial shaft end <NUM>'. The shaft <NUM>' has a shoulder <NUM>' formed thereon between the first groove 93A' and the second axial shaft end <NUM>'. A first clip <NUM>' is radially engaged in the first groove 93A'.

The first cam follower segment 10A' contains a first ball bearing <NUM>' and a second ball bearing <NUM>'. The first ball bearing <NUM>' includes a first inner ring <NUM>' and a first outer ring <NUM>'. A plurality of rolling elements in the form of a first plurality of spherical balls <NUM>' is disposed between the first inner ring <NUM>' and the first outer ring <NUM>'. A first seal <NUM>' extends radially between an axial end 50X' of the first inner ring <NUM>' and an axial end 40X' of the first outer ring <NUM>'. A second seal <NUM>' extends radially between an axial end 50Y' of the first inner ring <NUM>' and an axial end 40Y' of the first outer ring <NUM>'. The first seal <NUM>', the second seal <NUM>', an outer surface of the first inner ring <NUM>', and an inner surface of the first outer ring <NUM>' define a first annular cavity <NUM>'. The first plurality of spherical balls <NUM>' are retained radially between a first inner race <NUM>' of the first inner ring <NUM>' and a first outer race <NUM>' of the first outer ring <NUM>'.

The second ball bearing <NUM>' includes a second inner ring <NUM>' and a second outer ring <NUM>'. A plurality of rolling elements in the form of a second plurality of spherical balls <NUM>' is disposed between the second inner ring <NUM>' and the second outer ring <NUM>'. A third seal <NUM>' extends radially between an axial end 80X' of the second inner ring <NUM>' and an axial end 70X' of the second outer ring <NUM>'. A fourth seal <NUM>' extends radially between an axial end 80Y' of the second inner ring <NUM>' and an axial end 70Y' of the second outer ring <NUM>'. The third seal <NUM>', the fourth seal <NUM>', an outer surface of the second inner ring <NUM>', and an inner surface of the second outer ring <NUM>' define a second annular cavity <NUM>'. The second plurality of spherical balls <NUM>' are retained radially between a second inner race <NUM>' of the second inner ring <NUM>' and a second outer race <NUM>' of the second outer ring <NUM>'.

In the example depicted in <FIG>, the second axial shaft end <NUM>' engages a complementary bore in the housing <NUM>. A cylindrical shank surface 91A' of the shaft <NUM>' is defined between the first groove 93A' and the shoulder <NUM>' of the shaft <NUM>'. A first tire <NUM>' wraps around the first ball bearing <NUM>' and the second ball bearing <NUM>'. A first flange <NUM>' extends radially inward from a first axial tire end 100X' of the first tire <NUM>' and a second groove 93C' interrupts (e.g., extends radially outward into the tire and circumferentially therearound) a radially inward surface of the first tire <NUM>' proximate to a second axial tire end 100Y' of the first tire <NUM>'. The first flange <NUM>' axially abuts the axial end 40X' of the first outer ring <NUM>' and a second clip 93B', radially engaging the second groove 93C', axially abuts the axial end 70Y' of the second outer ring <NUM>'. An axial end 50X' of the first inner ring <NUM>' axially abuts the first clip <NUM>' and an axial end 80Y' of the second inner ring <NUM>' axially abuts a spacer <NUM>.

In one example, shown in <FIG>, the shaft <NUM> includes a lubrication passage <NUM> extending axially therethrough and having a branch connection 1000B extending radially outward therefrom. A plug 1000P is removably secured in the passage <NUM>, proximate the second end <NUM> of the shaft for sealing the passage <NUM>. The branch connection 1000B is configured for lubricating the housing <NUM> of portions of the necker machine. A grease fitting, such as a Zerk fitting (not depicted), is incorporated into the first axial shaft end <NUM>' to supply grease to the lubrication passage <NUM>.

The second cam follower segment 10B' contains a third ball bearing <NUM>" and a fourth ball bearing <NUM>''. The third ball bearing <NUM>" includes a third inner ring <NUM>" and a third outer ring <NUM>". A plurality of rolling elements in the form of a third plurality of spherical balls <NUM>" is disposed between the third inner ring <NUM>" and the third outer ring <NUM>". A fifth seal <NUM>" extends radially between an axial end 50X" of the third inner ring <NUM>" and an axial end 40X" of the third outer ring <NUM>". A sixth seal <NUM>" extends radially between an axial end 50Y" of the third inner ring <NUM>" and an axial end 40Y" of the third outer ring <NUM>". The fifth seal <NUM>", the sixth seal <NUM>", an outer surface of the third inner ring <NUM>", and an inner surface of the third outer ring <NUM>" define a third annular cavity <NUM>". The third plurality of spherical balls <NUM>" are retained radially between a third inner race <NUM>" of the third inner ring <NUM>" and a third outer race <NUM>" of the third outer ring <NUM>".

The fourth ball bearing <NUM>" includes a fourth inner ring <NUM>" and a fourth outer ring <NUM>". A plurality of rolling elements in the form of a fourth plurality of spherical balls <NUM>" is disposed between the fourth inner ring <NUM>" and the fourth outer ring <NUM>". A seventh seal <NUM>" extends radially between an axial end 80X" of the fourth inner ring <NUM>" and an axial end 70X" of the fourth outer ring <NUM>". An eighth seal <NUM>" extends radially between an axial end 80Y" of the fourth inner ring <NUM>" and an axial end 70Y'' of the fourth outer ring <NUM>". The seventh seal <NUM>", the eighth seal <NUM>'', an outer surface of the fourth inner ring <NUM>", and an inner surface of the fourth outer ring <NUM>" define a fourth annular cavity <NUM>". The fourth plurality of spherical balls <NUM>" are retained radially between a fourth inner race <NUM>" of the fourth inner ring <NUM>" and a fourth outer race <NUM>" of the fourth outer ring <NUM>''. The axial end 80X'' of the fourth inner ring <NUM>" axially abuts the axial end 50Y" of the third inner ring <NUM>" and the axial end 80Y" of the fourth inner ring <NUM>" axially abuts the shoulder <NUM>'. A second tire <NUM>" wraps around the third ball bearing <NUM>" and the fourth ball bearing <NUM>''. A second flange <NUM>" extends radially inward from a third axial tire end 100X" of the second tire <NUM>" and a third groove 93C" interrupts an inner surface of the second tire <NUM>" proximate to a fourth axial tire end 100Y". The second flange <NUM>" axially abuts the axial end 40X" of the third outer ring <NUM>" and a third clip 93B", radially engaging the third groove 93C", axially abuts the axial end 70Y" of the fourth outer ring <NUM>". An axial end 50X" of the third inner ring <NUM>" axially abuts the spacer <NUM> and an axial end 80Y" of the fourth inner ring <NUM>" axially abuts the shoulder <NUM>'. The spacer <NUM> is disposed on the shaft <NUM>' between and abutting the second inner ring <NUM>' and the third inner ring <NUM>". The first inner ring <NUM>', second inner ring <NUM>', the spacer <NUM>, the third inner ring <NUM>" and the fourth inner ring <NUM>" are axially fixed to the shaft <NUM>' by the first clip <NUM>' and the shoulder <NUM>.

In the example depicted in <FIG>, the first cam follower segment 10A' is spaced apart from the second cam follower segment 10B' by the spacer <NUM>. An axial stackup is defined as the total axial length of the first inner ring <NUM>', the second inner ring <NUM>', the spacer <NUM>, the third inner ring <NUM>", and the fourth inner ring <NUM>". The axial stackup is axially retained by the first clip 93A' engaging the first groove 93A' at one axial end and the shoulder <NUM>' at an opposite axial end.

In the example depicted in <FIG>, the first seal <NUM>' is fixed to the first outer ring <NUM>', the third seal <NUM>' is fixed to the second outer ring <NUM>', the fifth seal <NUM>" is fixed to the third outer ring <NUM>", and the seventh seal <NUM>" is fixed to the fourth outer ring <NUM>". The second seal <NUM>' is fixed to the first outer ring <NUM>', the fourth seal <NUM>' is fixed to the second outer ring <NUM>', the sixth seal <NUM>" is fixed to the third outer ring <NUM>", and eighth seal <NUM>" is fixed to the fourth outer ring <NUM>". While each of the seals is fixed to the respective outer ring, fixing each of the seals to the respective inner ring does not depart from the scope of the present disclosure.

In the example depicted in <FIG>, the geometry of the bearings <NUM>', <NUM>', <NUM>", <NUM>" is also selected to yield maximum load capacity for the end user's stipulated outer diameter of the tire <NUM>', <NUM>". The optimum load distribution and service life is obtained by controlling the internal clearance by press fitting the first tire <NUM>' over the first outer ring <NUM>' of the first bearing <NUM>' and the second outer ring <NUM>' of the second bearing <NUM>' and by press fitting the second tire <NUM>" over the third outer ring <NUM>" of the third bearing <NUM>" and over the fourth outer ring <NUM>" of the fourth bearing <NUM>".

In reference to <FIG>, an alternate example of a ram assembly <NUM>' for a necker machine has an inner follower <NUM>' and an outer follower <NUM>'. <FIG> depicts the inner follower <NUM>' and the outer follower <NUM>' riding on a rotating cam <NUM>'. The inner follower <NUM>' includes an outboard roller at a location marked with the arrow 11A' in the form of the first cam follower segment 10A' and an inboard roller at a location marked with the arrow 11B' in the form of the second cam follower segment 10B'. The outer follower <NUM>' includes an outboard roller at a location marked with the arrow 11C' in the form of the first cam follower segment 10A' and an inboard roller at a location marked with the arrow 11D' in the form of second cam follower segment 10B'. In the example depicted in <FIG>, the first cam follower segments 10A' and the second cam follower segments 10B' engage opposing surfaces of the rotating cam <NUM>'.

In <FIG>, 10C and 10D the increasing load is shown in the ordinate while the turret angle in degrees (e.g., cycle) is shown in the abscissa. <FIG> depicts the duty cycle load chart for the inboard roller or second tire 10B' of the inner follower <NUM>' wherein measured values of the inner inboard load as a function of turret angle is shown in the light solid line and the simplified inner inboard duty cycle is shown in the solid bold line. The simplified inner inboard duty cycle provides an efficient manner to analyze and/or utilize the measured inner inboard duty cycle and simplifies the life calculations. <FIG> depicts the duty cycle load chart for the inboard roller or fourth tire 10D' of the outer follower <NUM>' wherein measured values of the outer inboard load as a function of turret angle is shown in the light solid line and the simplified outer inboard duty cycle is shown in the solid bold line. The simplified outer inboard duty cycle provides an efficient manner to analyze and/or utilize the measured outer inboard duty cycle and simplifies the life calculations. <FIG> depicts the duty cycle load chart for the outboard roller or third tire 10C' of the outer follower <NUM>' wherein measured values of the outer outboard load as a function of turret angle is shown in the light solid line and the simplified outer outboard duty cycle is shown in the solid bold line. The simplified outer outboard duty cycle provides an efficient manner to analyze and/or utilize the measured outer outboard duty cycle and simplifies the life calculations. <FIG> depicts the duty cycle load chart for the outboard roller or first tire 10A' of the inner follower <NUM>' wherein measured values of the inner outboard load as a function of turret angle is shown in the light solid line and the simplified inner outboard duty cycle is shown in the solid bold line. The simplified inner outboard duty cycle provides an efficient manner to analyze and/or utilize the measured inner outboard duty cycle and simplifies the life calculations.

The resulting duty cycle life results for the rollers evaluated in <FIG> are shown in <FIG>. For the outer inboard roller or tire 10D', <FIG> illustrates an individual ball bearing life of <NUM>,<NUM> hours and a roller assembly life of <NUM>,<NUM> hours for a roller speed of <NUM> rotations per minute (RPM). For the outer outboard roller or tire 10C', <FIG> illustrates an individual ball bearing life of <NUM>,<NUM> hours and a roller assembly life of <NUM>,<NUM> hours for a roller speed of <NUM> rotations per minute (RPM). For the inner inboard roller or tire 10B', <FIG> illustrates an individual ball bearing life of <NUM>,<NUM> hours and a roller assembly life of <NUM>,<NUM> hours for a roller speed of <NUM> rotations per minute (RPM). For the inner outboard roller or tire 10A', <FIG> illustrates an individual ball bearing life of <NUM>,<NUM>,<NUM> hours and a roller assembly life of <NUM>,<NUM>,<NUM> hours for a roller speed of <NUM> rotations per minute (RPM).

<FIG> depict an axial retainment system <NUM> having a cam follower <NUM> for a ram of a necker machine according to an alternative embodiment of the present invention. As shown in <FIG>, the cam follower <NUM> includes a first ball bearing <NUM> and a second ball bearing <NUM>. The first ball bearing <NUM> and the second ball bearing <NUM> are configured in a tandem configuration. That is, they are positioned axially side to side, coaxially with a first axis of rotation A. In the embodiment shown, an inner ring <NUM> of the first ball bearing <NUM> and an inner ring <NUM> of the second ball bearing <NUM> are axially and radially fixed relative to each other about the first axis of rotation A.

As shown in <FIG>, he first ball bearing <NUM> includes a first outer ring <NUM> that has a first outer race <NUM> (also referred to as a bearing surface) and a first exterior surface <NUM>. The first ball bearing <NUM> further includes the first inner ring <NUM> which has a first inner race <NUM> (also referred to as a bearing surface). The first inner ring <NUM> is coaxially disposed in the first outer ring <NUM>. A first plurality of rolling elements <NUM> are disposed between the first outer race <NUM> and the first inner race <NUM>. The first plurality of rolling elements <NUM> are, for example, spherical balls. The first plurality of rolling elements <NUM> are in rolling engagement with the first outer race <NUM> and the first inner race <NUM> such that the first outer ring <NUM> is rotatable relative to the first inner ring <NUM> about the first axis of rotation A.

As shown in <FIG>, the first ball bearing <NUM> includes a second seal <NUM> extending radially between the first outer ring <NUM> and the first inner ring <NUM> on one side of the first plurality of rolling elements <NUM>. The first ball bearing <NUM> further includes a first seal <NUM> that extends radially between the first outer ring <NUM> and the first inner ring <NUM> such that the first plurality of rolling elements <NUM> is sealingly positioned between the first seal <NUM> and the second seal <NUM>. The first seal <NUM> and the second seal <NUM> are configured to retain a lubricant <NUM> inside an annular cavity <NUM> formed between the first outer race <NUM> and the first inner race <NUM> in which the first plurality of rolling elements <NUM> is disposed. The seals <NUM>, <NUM> are made of a molded nitrile rubber, however, as can be appreciated by a person having ordinary skill in the art and familiar with this disclosure, the seals <NUM>, <NUM>, also referred to as shields, can employ different materials in alternate embodiments.

The lubricant <NUM> is selected to be maintenance free and to function for the useful life of the cam follower <NUM>. In some embodiments, the lubricant <NUM> is a general-purpose wide temperature range grease having anti-oxidation and anti-wear properties.

In the embodiment disclosed in <FIG>, the second ball bearing <NUM> is similar in configuration to the first ball bearing <NUM>. The second ball bearing <NUM> includes a second outer ring <NUM> that has a second outer race <NUM> (also referred to as a bearing surface) and a second exterior surface <NUM>. The second ball bearing <NUM> further includes a second inner ring <NUM> that has a second inner race <NUM> (also referred to as a bearing surface). The second inner ring <NUM> is coaxially disposed in the second outer ring <NUM>. A second plurality of rolling elements <NUM> are disposed between the second outer race <NUM> and the second inner race <NUM>. The second plurality of rolling elements <NUM> are, for example, spherical balls. The second plurality of rolling elements <NUM> are in rolling engagement with the second outer race <NUM> and the second inner race <NUM> such that the second outer ring <NUM> is rotatable relative to the second inner ring <NUM> about the first axis of rotation A.

As shown in <FIG>, the second ball bearing <NUM> includes a third seal <NUM> that extends radially between the second outer ring <NUM> and the second inner ring <NUM> on one side of the second plurality of rolling elements <NUM>. The second bearing <NUM> further includes a fourth seal <NUM> that extends radially between the second outer ring <NUM> and the second inner ring <NUM> such that the second plurality of rolling elements <NUM> are sealingly positioned between the third seal <NUM> and the fourth seal <NUM>. The seals <NUM>, <NUM> are configured to retain the lubricant <NUM> inside an annular cavity <NUM> formed between the second outer race <NUM> and the second inner race <NUM>. The second plurality of rolling elements are disposed in the annular cavity <NUM>. The seals <NUM>, <NUM> are made of a molded nitrile rubber, however, as can be appreciated by a person having ordinary skill in the art and being familiar with this disclosure, the seals <NUM>, <NUM>, also referred to as shields, can employ different materials in alternate embodiments.

In reference to the embodiment shown in <FIG>, although the cam follower <NUM> is shown having a first ball bearing <NUM> and a second ball bearing <NUM>, the present invention is not limited in this regard and, as will be appreciated by a person of ordinary skill in the art, many different configurations may be employed. For example, the present invention is practiced using a cam follower having a single row of roller or ball bearings. Or, for example, in one embodiment the present invention is practiced using a cam follower having a ball bearing wherein a single continuous outer ring defines a first outer race and a second outer race, and a single continuous inner ring defines a first inner raceway and a second inner raceway.

In the embodiment shown in <FIG>, the outer ring <NUM>, the outer ring <NUM>, the inner ring <NUM>, and/or the inner ring <NUM> are manufactured from a <NUM> steel that is through hardened. The first plurality of rolling elements <NUM> and the second plurality of rolling elements <NUM> also are manufactured from a <NUM> steel. As discussed herein regarding <FIG>, which is also representative of the first bearing <NUM> and the second bearing <NUM> of the cam follower <NUM> shown and discussed herein regarding <FIG>, each of the first plurality of rolling elements <NUM> are separated by a cage <NUM>; and each of the second plurality of rolling elements <NUM> are separated by another cage <NUM>. The cages <NUM> are manufactured from a low carbon soft steel. It should be understood that the present invention is not limited to using the cage <NUM> to separate adjacent rolling elements <NUM> from one another and another cage <NUM> to separate adjacent rolling elements <NUM>, as different spacers, or no spacers, may be employed between the balls in the first plurality of rolling elements <NUM> and as different spacers, or no spacers, may be employed between the balls in the second plurality of rolling elements <NUM>. It should also be understood that the present invention is not limited to balls, as other types of rolling elements may be employed with the present invention, for example, needle rollers.

In reference to <FIG>, the first inner ring <NUM> has a first bore <NUM> extending therethrough, and the second inner ring <NUM> has a second bore <NUM> extending therethrough. A shaft <NUM> is received through the first bore <NUM> and the second bore <NUM>. The shaft <NUM> is press fit in the first bore <NUM> and the second bore <NUM> such that the first inner ring <NUM> and the second inner ring <NUM> are fixed relative to the shaft about the first axis of rotation A. The shaft <NUM> (also referred to as a stud) extends between a first axial end <NUM> (also referred to as an outboard end) and a second axial end <NUM> (also referred to as an inboard end). The shaft <NUM> has a swaged ridge <NUM> formed thereon. The swaged ridge <NUM> extends radially outward from the shaft <NUM> and circumferentially around the shaft <NUM> (e.g., continuously around). The swaged ridge <NUM> is located proximate the first axial end <NUM> of the shaft <NUM>.

As shown in <FIG>, the first ball bearing <NUM> and the second ball bearing <NUM> axially abut one another and are received on the shaft <NUM> proximate to the first axial end <NUM>, thereof. The shaft <NUM> has a flange <NUM> projecting radially outward from the shaft <NUM>. The flange <NUM> is located between the first axial end <NUM> and the second axial end <NUM>. The flange <NUM> extends radially outward from the shaft <NUM> and circumferentially around the shaft <NUM> (e.g., continuously around). The flange <NUM> has an outboard axial surface 392B having a shoulder 392A extending axially outward therefrom toward the first axial end <NUM>. Once assembled, the second inner ring <NUM> abuts the shoulder 392A to inhibit axial movement of the ball bearings <NUM>, <NUM> relative to the shaft <NUM>. The first inner ring <NUM> abuts an inboard axial surface 393B of the swaged ridge <NUM>, such that the first inner ring <NUM> of first ball bearing <NUM> and the second inner ring <NUM> of the second ball bearing <NUM> are disposed, compressed, and retained axially between the swaged ridge <NUM> and the shoulder 392A.

As shown in <FIG>, a tire <NUM> extends circumferentially around the first outer ring <NUM> and the second outer ring <NUM>. A groove <NUM> is formed in tire <NUM> proximate an inboard axial end <NUM> thereof. The groove <NUM> extends circumferentially around and radially outward into the tire <NUM>. The groove <NUM> is located proximate an inner axial end of the second outer ring <NUM>. An outboard axial end <NUM> of the tire <NUM> has a radially inward projecting flange <NUM> located proximate an outboard axial end of the first outer ring <NUM> proximate to the first axial end <NUM> of the shaft <NUM>. A clip <NUM> is seated in the groove <NUM> to axially retain first outer ring <NUM> and the second outer ring <NUM> between the clip <NUM> and the flange <NUM> and to inhibit axial movement of the ball bearings <NUM>, <NUM> relative to the shaft <NUM>. The swaged ridge <NUM> engages the inner ring <NUM> of the first ball bearing <NUM> to axially secure the first ball bearing <NUM> on the shaft <NUM> and clip <NUM> engages the outer ring <NUM> of the second ball bearing <NUM> to axially secure the second ball bearing <NUM> to the tire <NUM>. The second inner ring <NUM> abuts the shoulder 392A of the shaft <NUM> such that the first inner ring <NUM> and the second inner ring <NUM> are fixed relative to one another and fixed relative to the A axis along the shaft <NUM>. The first ball bearing <NUM> and the second ball bearing <NUM> are located symmetrically on opposing sides of an apex R' of the cam follower crown radius R such that the first ball bearing <NUM> and the second ball bearing <NUM> axially abut one another under the apex R' to optimize load distribution. To accomplish this symmetry, the swaged ridge <NUM> and the clip <NUM> are positioned about the shaft <NUM> such that the swaged ridge <NUM> and the clip <NUM> are equidistant from the center axis B. This allows for equalization of load sharing by the first ball bearing <NUM> and the second ball bearing <NUM> for improved performance compared to prior art cam followers.

As shown in <FIG>, a tire <NUM> according to an alternative embodiment of the present invention extends circumferentially around the first outer ring <NUM> and the second outer ring <NUM>. An outboard axial end <NUM> of the tire <NUM> has a radially inward projecting flange <NUM> located proximate an outboard axial end 340A of the first outer ring <NUM>. An inboard axial end <NUM> of the tire <NUM> has an angled abutment shoulder <NUM> proximate an inboard axial end 370B of the second outer ring <NUM>. The tire <NUM> has an interior surface <NUM> extending between the flange <NUM> and the angled abutment shoulder <NUM>.

As shown in <FIG>, the flange <NUM> has a first radial length H3 as measured from the interior surface <NUM> to a radially inward facing surface 612E of the flange <NUM>. The angled abutment shoulder <NUM> has a second radial length H4 as measured from the interior surface <NUM> to a radially inward facing surface 618E. In some embodiments, the first radial length H3 is about equal to an annular thickness H5 of the first outer ring <NUM> and the second outer ring <NUM>. In some embodiments, the second radial length H4 is less than the first radial length H3. In some embodiments, the second radial length H4 is less than about <NUM>% of the first radial length H3. In some embodiments, the second radial length H4 is less than about <NUM>% of the first radial length H3. In some embodiments, the second radial length H4 is less than about <NUM>% of the first radial length H3. In some embodiments, the second radial length H4 is less than the annular thickness H5. In some embodiments, the second radial length H4 is less than about <NUM>% of the annular thickness H5. In some embodiments, the second radial length H4 is less than about <NUM>% of the annular thickness H5. In some embodiments, the second radial length H4 is less than about <NUM>% of the annular thickness H5.

As shown in <FIG>, the angled abutment shoulder <NUM> has an outboard sloped abutment surface 618A that extends and slopes radially and axially inward from the interior surface <NUM> to the radially inward facing surface 618E. A portion of the outboard sloped abutment surface 618A abuts a portion of the inboard axial end 370B of the second outer ring <NUM>. The outboard sloped abutment surface 618A is sloped at a first angle θ1 measured away from (e.g., axially inwardly away) a first radial line R3. In some embodiments, the first angle θ1 is between <NUM> degrees and <NUM> degrees. In some embodiments, the first angle θ1 is between <NUM> degrees and <NUM> degrees. In some embodiments, the first angle θ1 is between <NUM> degrees and <NUM> degrees. In some embodiments, the first angle θ1 is between <NUM> degrees and <NUM> degrees. In some embodiments, the first angle θ1 is between <NUM> degrees and <NUM> degrees. In some embodiments, the first angle θ1 is less than <NUM> degrees. The outboard sloped abutment surface 618A has an axial width W6.

As shown in <FIG>, the angled abutment shoulder <NUM> has an inboard sloped relief surface 618B that extends and sloped radially inward and axially outward from the inboard axial end <NUM> to the radially inward facing surface 618E. The inboard sloped relief surface 618B is sloped at a second angle θ2 measured away from (e.g., axially outwardly away) a second radial line R4. In some embodiments, the second angle θ2 is between about <NUM> degrees and <NUM> degrees. In some embodiments, the second angle θ2 is between about <NUM> degrees and <NUM> degrees. In some embodiments, the second angle θ2 is between about <NUM> degrees and <NUM> degrees. In some embodiments, the second angle θ2 is between about <NUM> degrees and <NUM> degrees. The inboard sloped relief surface 618B has an axial width W7. The inboard sloped relief surface 618B and the outboard sloped abutment surface 618A are sloped and extend axially toward each other such that the radially inward facing surface 618E has an axial width W2 that is less than an overall axial width W3 of the angled abutment shoulder <NUM>.

As shown in <FIG>, the interior surface <NUM> has a first axial width W4 measured between: (<NUM>) a first junction 612X of the flange <NUM> and the interior surface <NUM>; and (<NUM>) a second junction 618X of the angled abutment shoulder <NUM> and the interior surface <NUM>. The tire <NUM> defines a second axial width W5 measured between: (<NUM>) an inboard surface 612B of the flange <NUM>; and (<NUM>) a third junction 618Y between the outboard sloped abutment surface 618A and the radially inward facing surface 618E.

The outboard sloped abutment surface 618A has utility in reducing or eliminating axial movement of the first outer ring <NUM> and the second outer ring <NUM> relative to the tire <NUM> by a compensating feature for stack-up tolerances. When a combined axial width W1 of the first outer ring <NUM> and the second outer ring <NUM> is less than the axial width W5, the first outer ring <NUM> and the second outer ring <NUM> will still engage a portion of the outboard sloped abutment surface 618A to axially compress the first outer ring <NUM> and the second outer ring <NUM> between the outboard sloped abutment surface 618A and the inboard surface 612B. The swaged ridge <NUM> engages the first inner ring <NUM> to axially secure the first ball bearing <NUM> on the shaft <NUM> and the sloped abutment shoulder <NUM> engages the second outer ring <NUM> to axially secure the second ball bearing <NUM> to the tire <NUM>. The second inner ring <NUM> abuts the shoulder 392A of the shaft <NUM> such that the first inner ring <NUM> and the second inner ring <NUM> are fixed relative to one another and fixed relative to the A axis along the shaft <NUM>. The first ball bearing <NUM> and the second ball bearing <NUM> are located symmetrically on opposing sides of the apex R' of the cam follower crown radius R such that the first ball bearing <NUM> and the second ball bearing <NUM> axially abut one another under the apex R' to optimize load distribution. To accomplish this symmetry, the swaged ridge <NUM> and the sloped abutment shoulder <NUM> are positioned about the shaft <NUM> such that the swaged ridge <NUM> and the sloped abutment shoulder <NUM> are equidistant from the center axis B. This allows for equalization of load sharing by the first ball bearing <NUM> and the second ball bearing <NUM> for improved performance compared to prior art cam followers.

The sloped abutment shoulder <NUM> has utility in the installation by press fitting of the first outer ring <NUM> and the second outer ring <NUM> into the tire <NUM>. For example, the radial length H4 is of a predetermined magnitude to allow radially outward deflection of the sloped abutment shoulder <NUM> to allow the first outer ring <NUM> and the second outer ring <NUM> to be pressed axially into the tire <NUM> without the need for special tools. The inboard sloped relief surface 618B and the axial width W7 thereof are configured to facilitate entry of the first outer ring <NUM> and the second outer ring <NUM> into the tire <NUM> and to provide sufficient support to maintain axial compression of the first outer ring <NUM> and the second outer ring <NUM> between the outboard sloped abutment surface 618A and the inboard surface 612B.

As shown in <FIG>, the shaft <NUM> includes a face <NUM> at the first axial end <NUM> perpendicular to the first axis of rotation A. The face <NUM> has a recessed hexagonal socket <NUM> (also referred to as a torque transmission aperture) configured to receive a hex wrench, or the like, for rotating the shaft <NUM> about the first axis of rotation A. As shown in <FIG>, the hexagonal socket <NUM> has a radially inward facing engagement surface 395A that is spaced apart from a radially innermost portion of an outboard axial surface 393A of the swaged ridge <NUM> by a neutral zone that extends a predetermined radial distance H1. In some embodiments, the radial distance H1 is about <NUM>% of an outboard diameter D4 of the shaft <NUM> as measured at the first bore <NUM> of the first bearing <NUM> and the second bore <NUM> of the second bearing <NUM> (i.e. the outboard diameter D4 is the diameter of the first axial end <NUM> of the shaft <NUM> before the formation of the swaged ridge <NUM>). This way, the neutral zone prevents deformation of the engagement surface 395A during formation of the swaged ridge <NUM>, as discussed below. The shaft <NUM> further includes a plurality of threads <NUM> on a radial outside surface 397A of the shaft <NUM>. In this way, the shaft <NUM> can be received in a bore (not shown) comprising a complementary thread pattern or can similarly be received in a nut or the like having a complementary thread pattern. In some embodiments, the shaft also includes a hollow portion <NUM> as discussed herein regarding <FIG>. This allows for weight reduction of shaft <NUM> for efficiency of operation, thus allowing additional mass of a tire <NUM>, as described herein.

<FIG> shows the swaged ridge <NUM> as depicted in Detail B of <FIG>. The swaged ridge <NUM> has an outboard axial surface 393A that faces toward the first axial end <NUM> of the shaft <NUM>. The outboard axial surface 393A extends radially outward from a first cylindrical surface 390A of the shaft <NUM> and terminates at a radially outward facing circumferential surface 393C. The swaged ridge <NUM> has an inboard axial surface 393B that faces toward the second axial end <NUM> of the shaft <NUM>. The inboard axial surface 393B extends radially outward from a second cylindrical surface 390B of the shaft <NUM> and terminates at the radially outward facing circumferential surface 393C. The shaft <NUM> has a swage diameter D8 as measured at the radially outward facing circumferential surface 393C. In some embodiments, the swage diameter D8 is about <NUM>% to about <NUM>% larger than the outboard diameter D4. The outboard axial surface 393A is recessed axially inward from the first axial end <NUM> an axial distance D2. In some embodiments, the axial distance D2 is between about <NUM> and <NUM>. In some embodiments, the axial distance D2 is about <NUM>. The outboard axial surface 393A is substantially flat and extends radially outward a radial distance H2 from the first cylindrical surface 390A. In some embodiments, the radial distance H2 is between about <NUM> and <NUM>. In some embodiments, the radial distance H2 is about <NUM>. The inboard axial surface 393B is swaged against, conforms in shape to, and is compressed against the first inner ring <NUM> of the first bearing <NUM>. Thus, depending on the shape of the first inner ring <NUM>, the inboard axial surface 393B is substantially flat, arcuate, beveled, or the like. For example, in the embodiment shown in <FIG>, the inboard axial surface 393B is arcuate. The swaged ridge <NUM> retains the ball bearings <NUM>, <NUM> on the shaft <NUM> such that an outboard axial surface 350A of the first inner ring <NUM> is positioned axially inward from the first axial end <NUM> of the shaft <NUM> an axial distance D3. In some embodiments, the axial distance D3 is about <NUM>% of the combined axial width W1 of the ball bearings <NUM>, <NUM>, as shown in <FIG>. In some embodiments, the axial distance D3 is between <NUM>% and <NUM>% of the combined axial width W1 of the ball bearings <NUM>, <NUM>.

<FIG> show a swage die <NUM> according to an embodiment of the present invention. The swage die <NUM> is used in a process of forming the cam follower <NUM> of the axial retainment system <NUM> discussed herein regarding <FIG>. The swage die <NUM> has a body <NUM> having a first end <NUM> and a second end <NUM> opposite the first end <NUM> along a longitudinal axis L. The first end <NUM> is mountable to a pressing device (e.g., a hydraulic press) via a bore <NUM> in the body <NUM>. The swage die has a cylindrical extension <NUM> that extends outward from the second end <NUM> away from the first end <NUM> along the longitudinal axis L. The cylindrical extension <NUM> has an end face <NUM> having a cylindrical punch cavity <NUM> therein. The punch cavity <NUM> forms the swaged ridge <NUM> on the shaft <NUM> when the end face <NUM> of the swage die <NUM> engages and presses against the first axial end <NUM> of the shaft <NUM>.

As shown in <FIG>, the punch cavity <NUM> is positioned radially inward a radial distance D5 from an outer edge <NUM> of end face <NUM>. The radial distance D5 corresponds to the radial distance H2 of the outboard axial surface 393A of the swaged ridge <NUM>. In some embodiments, the radial distance D5 is between about <NUM> and <NUM>. In some embodiments, the radial distance D5 is about <NUM>. The punch cavity <NUM> has an interior wall <NUM> and a recessed surface <NUM>. The recessed surface <NUM> is recessed an axial distance D6 from the end face <NUM>. The axial distance D6 corresponds to the axial distance D2 of the outboard axial surface 393A of the swaged ridge <NUM>. In some embodiments, the axial distance D6 is between about <NUM> and <NUM>. In some embodiments, the axial distance D6 is about <NUM>. The cylindrical extension <NUM> has a hollow portion <NUM> extending inward from an opening <NUM> centrally located in the recessed surface <NUM>. The opening <NUM> is positioned radially inward a radial distance D7 from the interior wall <NUM>. The radial distance D7 corresponds to the radial distance H1 of the first axial end <NUM> of the shaft <NUM>. In some embodiments, the radial distance D7 is about <NUM>% of the outboard diameter D4. The opening <NUM> corresponds in size to the torque transmission aperture <NUM> of the shaft <NUM> to further prevent deformation of the engagement surface 395A during formation of the swaged ridge <NUM>.

To form the swaged ridge <NUM> on the shaft <NUM>, the first axial end <NUM> of the shaft <NUM> is inserted through the bore <NUM> of the second bearing <NUM> and the bore <NUM> of the first bearing <NUM> such that the second inner ring <NUM> abuts the shoulder 392A, the first inner ring <NUM> abuts the second inner ring <NUM>, and the outboard axial surface 350A of the first inner ring <NUM> is positioned axially inward from the first axial end <NUM> of the shaft <NUM> the axial distance D3. The shaft <NUM> is secured in a fixture (not shown) with the first axial end <NUM> extending outwardly from the fixture. The punch cavity <NUM> of the swage die <NUM> is placed against the first axial end <NUM> of the shaft <NUM>. The swage die <NUM> is pressed against the first axial end <NUM> of the shaft <NUM> to mechanically upset the material of the shaft <NUM> to form the swaged ridge <NUM> on the shaft <NUM> such that the swaged ridge <NUM> has the outboard axial surface 393A, the radially outward facing circumferential surface 393C, and the inboard axial surface 393B that conforms in shape to and compresses against the first inner ring <NUM>, as discussed above. In some embodiments, a minimum pressing force of <NUM> tons is required to form the swaged ridge <NUM> on the shaft <NUM>. As shown in <FIG>, the swaging process described herein permits the first axial end <NUM> of the shaft <NUM> to be flush with, or recessed within, the outboard end of the tire <NUM>, which is required for successful operation of the flange forming station of a necker machine. The swaging process described herein also encourages the swaged material to flow radially outward (forming the swaged ridge <NUM>) rather than both radially outward and radially inward because the swaged material flowing radially inward risks deforming the engagement surface 395A of the torque transmission aperture <NUM> and reducing the functionality of the torque transmission aperture <NUM>.

A visual inspection system is used to verify that the swage diameter D8 is within an acceptable range (e.g., between about <NUM>% to about <NUM>% larger than the outboard diameter D4). The inventors have surprisingly discovered that a visual inspection system can be used to differentiate between the subtle distinctions in color between adjacent surfaces to measure the swage diameter D8. For example, in some embodiments, the shaft <NUM> is treated with a black oxide process such that its steel surfaces have a chemical conversion coating formed thereon that appears black, and the ball bearing <NUM> is not treated with the black oxide process such that its steel surfaces have a lighter-colored appearance relative to the black oxide coated shaft <NUM> (such as a gray-colored appearance) such that the visual inspection system scans the outboard face <NUM> and differentiates between the black-colored radially outward facing circumferential surface 393C of the swaged ridge <NUM> and the lighter-colored gray outboard axial surface 350A of the first inner ring <NUM> to measure the swage diameter D8. In some embodiments, the material of the shaft <NUM> displaced during the swaging process to form the swaged ridge <NUM> is discolored from its engagement with the swage die <NUM> and has a darker (almost black) appearance relative to the non-swaged lighter-colored machined material of the ball bearing <NUM> such that the visual inspection system scans the outboard face <NUM> and differentiates between the subtle color distinctions between the radially outward facing circumferential surface 393C and the inner ring <NUM> to measure the swage diameter D8. In some embodiments, a method of visually inspecting the shaft <NUM> is used to confirm the swage diameter D8 is within the acceptable range of about <NUM>% to about <NUM>% larger than the outboard diameter D4. The method includes a visual inspection system configured to scan a face of an object, differentiate between at least two contrasting colors of at least two adjacent surfaces of the object, and measure a distance along the face of the object. The method uses the visual inspection system to scan the first axial end <NUM> of the shaft <NUM>, differentiate between a first color of the swaged ridge <NUM> and a second contrasting color of the first bearing <NUM>, and measure the swage diameter D8 of the swaged ridge <NUM> at the radially outward facing circumferential surface 393C. In some embodiments, the first color of the swaged ridge <NUM> is darker relative to the second contrasting color of the first bearing <NUM>.

The first ball bearing <NUM> and the second ball bearing <NUM> are received in the tire <NUM> or the tire <NUM>. In some embodiments, the tires <NUM>, <NUM> are made from a metallic material. In one embodiment, the tires <NUM>, <NUM> are made from steel. In a particular embodiment, the tires <NUM>, <NUM> are made from carburized steel and includes an optional black oxide coating for maximum wear resistance. It should be appreciated that in alternate embodiments different tire materials and different tire sizes are used for the tires <NUM>, <NUM>. Further, the cam follower <NUM> is versatile in that in some embodiments the tires <NUM>, <NUM> are interchangeable with, for example, tires made of other metallic materials and tires made from elastomers, polymers or combinations thereof. The tires <NUM>, <NUM> each have an exterior surface <NUM>, <NUM>, which includes a crown radius R and an apex R'. The crown radius R is bowed about the center axis B, which is substantially perpendicular to axis A. The tires <NUM>, <NUM> each include a flange <NUM>, <NUM>. The flanges <NUM>, <NUM>, in cooperation with an axial retainment feature, such as the clip <NUM> disposed in the groove <NUM> of tire <NUM> or the angled abutment shoulder <NUM> of tire <NUM>, axially secure the first outer ring <NUM> and the second outer ring <NUM> to the tires <NUM>, <NUM> such that the tires <NUM>, <NUM> are axially fixed to the first ball bearing <NUM> and the second ball bearing <NUM>. As shown in <FIG>, tire <NUM> has a thickness T1. The exterior surfaces <NUM>, <NUM> of the tires <NUM>, <NUM> engage the cam (not shown) during operating of the necker in accordance with the present invention.

A pitch radius PR is defined as the distance between the midpoint C of any one of the first plurality of rolling elements <NUM> and the axis A as shown in <FIG>. The pitch radius PR is also defined as the distance between the midpoint of any one of the second plurality of rolling elements <NUM> and the axis A as shown in <FIG>. The ratio of the thickness T1 of the tire <NUM> to the pitch radius PR (i.e., T1 divided by PR) is between about <NUM> and about <NUM>. Further, the ratio of the depth D1 of the groove <NUM> (that the clip <NUM> is disposed in) to the thickness T1 of the tire <NUM> (i.e., D1 divided by T1) is between about <NUM> and about <NUM>. The outboard radial height H2 of the radially outward facing circumferential surface 393C of the swaged ridge <NUM> are sized to provide a sufficient thickness of material to withstand axial forces and to axially retain the first outer ring <NUM> and the second outer ring <NUM> at a fixed axial position on the shaft <NUM> while allowing the first outer ring <NUM> and the second outer ring <NUM> to rotate around the shaft <NUM>. The about <NUM> to about <NUM> ratio of the depth D1 of the groove <NUM> to the tire thickness T1 also allows for minimization of the weight of the (e.g. metallic) tire <NUM> while maintaining sufficient material thickness of the tire <NUM> to meet strength and wear requirements for the tire <NUM>. In some embodiments, the depth D1 of the groove <NUM> is determined by the length of the clip <NUM> such that the ratio of the depth D1 to the tire thickness T1 is smaller or larger than the about <NUM> to about <NUM> range discussed above.

In reference to <FIG> and <FIG>, a ram assembly <NUM> for a necker machine (not shown) in accordance with the present invention is shown. In such a can making necker machine, a cam follower rides on a rotating cam <NUM> with the rotational axis AC parallel to the surface of the cam <NUM>. The ram assembly <NUM> extends between a first axial end <NUM> and a second axial end <NUM>. The ram assembly <NUM> includes a fixed bushing <NUM> having a bore extending therethrough between the first axial end <NUM> and the second axial end <NUM>. A ram piston <NUM> extends through both ends of the bore of the fixed bushing <NUM>. Proximate to the second axial end of the ram <NUM>, two cam followers (similar to the cam follower <NUM> illustrated in <FIG> and described in detail herein) extend radially therefrom. Referring to <FIG>, the cam followers <NUM>, including a first roller <NUM> and a second roller <NUM>, ride on a surface of a cam <NUM>, with one roller <NUM>, <NUM> located on each side of the cam <NUM>, as the rollers rotate around the rotational axis of the cam AC. The ram <NUM> is moved back and forth along the axis AR by the attached rollers <NUM>, <NUM> in an accelerating and decelerating movement following a profile of the cam <NUM>. Considerable radial force (i.e., force along the cam radial axis RC) is developed on the rollers <NUM>, <NUM> during the can necking operation.

The geometry of the first ball bearing <NUM> and the second ball bearing <NUM> is selected to yield maximum load capacity and to allow the end user to stipulate the outer diameter of the tire <NUM>, as previously discussed. Specifically, the geometry of the rolling elements <NUM>, <NUM>, the inner rings <NUM>, <NUM>, and the outer rings <NUM>, <NUM> are adjusted to minimize the internal clearance C1, C2 in the respective bearing <NUM>, <NUM> thereby optimizing load distribution and service life, as discussed herein regarding <FIG>, which is also representative of the first bearing <NUM> and the second bearing <NUM> as discussed herein regarding <FIG>. Press fitting the interior surface <NUM> of the tire <NUM> over the outer rings <NUM>, <NUM> adjusts the internal clearance C1, C2. Generally, ball bearings have an industry standard internal clearance or looseness, which is reduced by the interference press fit of the outer rings <NUM>, <NUM> into the tire <NUM>. By reducing this internal clearance C1, C2, more rolling elements <NUM>, <NUM> within each bearing <NUM>, <NUM> share the applied load, thereby increasing and optimizing the bearing life. In some embodiments, the internal clearance is between about <NUM> and <NUM>. The applied load per duty cycle is discussed above with regards to <FIG>, which are also representative of the cam follower <NUM> discussed herein regarding <FIG>. A radial distance R1 is defined by the radial distance from the exterior surfaces <NUM>, <NUM> of the outer rings <NUM>, <NUM> to the shaft axis A. A radial distance R2 is defined by the radial distance from shaft axis A to an interior surface <NUM> of the tire <NUM>. The ratio of R1 to R2 is adjusted to optimize the load distribution. By maintaining a R1:R2 ratio between about <NUM> and about <NUM>, improved load sharing and longer bearing life is realized.

The design of the ball bearings disclosed herein adjusts the aforementioned internal clearance for optimum load distribution and service life. In some embodiments, the interference press fit into the cam follower wheel ranges from <NUM> to <NUM> of interference fit, resulting in an internal clearance at or near <NUM>.

Claim 1:
A cam follower (<NUM>) comprising:
an outer ring (<NUM>) having an outer ring bearing surface (<NUM>) and an exterior surface (<NUM>);
an inner ring (<NUM>) coaxially disposed in the outer ring (<NUM>) and having an inner ring bearing surface (<NUM>), the inner ring having a bore (<NUM>) extending therethrough;
a plurality of rolling elements (<NUM>) disposed in an annular cavity between the outer ring bearing surface (<NUM>) and the inner ring bearing surface (<NUM>), the plurality of rolling elements (<NUM>) being in rolling engagement with the outer ring bearing surface (<NUM>) and the inner ring bearing surface (<NUM>) such that the outer ring (<NUM>) is rotatable relative to the inner ring (<NUM>) about a shaft axis A;
a shaft (<NUM>) extending from a first axial end (<NUM>) to a second axial end (<NUM>) thereof, the shaft (<NUM>) being fixedly received in the bore (<NUM>) in the inner ring (<NUM>), the shaft (<NUM>) having a circumferential flange (<NUM>) extending radially outward from the shaft (<NUM>) and located between the first axial end (<NUM>) and the second axial end (<NUM>), characterized in
that the shaft (<NUM>) has a swaged ridge (<NUM>) formed at the first axial end (<NUM>) extending radially outward and extending circumferentially around the shaft (<NUM>),
that the inner ring (<NUM>) is axially retained on the shaft (<NUM>) by the swaged ridge (<NUM>) and the flange (<NUM>),
that the swaged ridge (<NUM>) extends radially outward from the shaft (<NUM>) and circumferentially continuously around the shaft (<NUM>), and
that the shaft (<NUM>) has an outboard diameter as measured proximate the first axial end, and the swaged ridge has a swage diameter as measured at the radially outward facing circumferential surface, whereby the swage diameter is greater than the outboard diameter.