JPS58174721A - Journal crossed member of universal joint and its manufacture - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a Cardan-type universal joint which includes a journal cross having a radially extending cylindrical trunnion for connecting bifurcated branches extending from paired rotating members. It is known that the device is equipped with a member. More specifically, the present invention relates to a lubrication system for a trunnion-bifurcated coupling device and a method of manufacturing the same.

The trunnions of such universal joints are usually supported in needle roller bearings, which in turn are supported in cup-shaped bearing races, and these races are mounted within their respective forked members to provide friction. are related. Each race has an annular body consisting of a needle bearing as described above physically interposed between the inner periphery of the race and the mating trunnion, so that there is virtually no friction between the trunnion and the bearing race. Exercise is taking place.

Conventional trunnion materials are ground to provide a highly polished finish for rolling contact with needle roller bearings. Such bearing systems, often referred to as anti-friction bearings, have very smooth surfaces, but these surfaces do not resist aggressive movement during limited oscillating or oscillatory movements of the type that occur when using universal joints. oil cannot be circulated satisfactorily. As is well known, anti-friction bearings tend to rely on continuous rotational movement of the bearing member to obtain adequate lubrication. Since the rotation of the bearing combined with the universal joint is only partial,
Less oil circulation than desired results in relatively unsatisfactory joint performance. Additionally, in unclean and/or corrosive environments, the lack of sufficient lubrication is critical and premature failure of bearing trunnion systems frequently occurs. humid and/or 11
□111 Under corrosive environments, erosive corrosion also occurs, further increasing wear and thus accelerating the deterioration of bearing trunnion couplings.

This invention relates to a type of anti-friction device that typically has a smooth and/or ground profile in a universal joint.
An improved lubrication system for bearing trunnion systems is provided.

A plurality of closely spaced and/or precisely spaced lands and lubricating groups are disposed circumferentially around each trunnion, the lands forming a contact surface of the sump of the needle roller bearing. The group provides a means for retaining lubricant between the bearing surface and the trunnion surface. In one preferred embodiment, the lands and groups are each uniformly and alternately spaced, and the lands and groups are oriented in a half plane approximately perpendicular to the longitudinal axis of the trunnion. It is attached. In another preferred embodiment, the lands and groups are partially and randomly discontinuous around the circumference of each trunnion.

The preferred method of manufacturing this improved cross member includes mechanical and heat treatment steps, without typical intermediate or final grinding steps. Another preferred method of manufacture includes roll parnising the trunnion lands prior to heat treatment.

Embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

A type of cross member aα used in a universal joint (not shown)
is shown in Figure 1. In this embodiment, the cross member 1IO1 comprises four modified trunnions α→, each trunnion extending along the longitudinal axis A-A or B-B of the central body portion (6).
Each trunnion extends radially outward along the
The needle roller bearing CIQ is covered. This bearing αQ consists of a plurality of needle roller bearings (24) housed in a cup-shaped bearing race (22). The cylindrical body part of the trunnion (14) is the bearing race (22)
It is provided with an end Oa that contacts and slides with the thrust surface (20) of the inner pair. The bearing (24) is a bearing race (22
) and the cylindrical outer surface of the trunnion 04. Within the bearing race (22), an elastomeric friction ring (26) is supported, as is well known, to ensure proper radial positioning of the needle roller bearing (24). Annular elastomeric sealing member (
28) serves to protect the shaft from dust and other contaminants from the outside world. The sealing member (28) also serves to retain lubricant within the bearing cavity (8).

FIG. 2 shows a part of an embodiment of the improved trunnion 04 of the cross member αα. The trunnion 04 has alternating spaced hills or lands (30) and groups (32) for retaining oil on its cylindrical surface. Run)” (30) and group (32) are shown with the suffix A, B in Figures 2 to 5 for clarity purposes.
, C, and D. Figures 4 and 5 more particularly show two preferred embodiments of lands (30) and groups (32). In both examples, the group (32)
lubricates the land (30) of the trunnion and the needle bearing (24) rolling over it, since the land (30) forms the actual contact surface of the bearing roller between the trunnion (14) and the needle bearing (24). The group (32) shown in FIG.
) is formed by a machine tool such as a lathe or a mill.
represents one embodiment. However, the group in Figure 5 (3
2) shows an example also formed by a similar machine tool, but in this case the bottom of the group -(2)
Roll burnishing is subsequently carried out in order to create projections (29) on both sides of the group (32) that slightly overlap 7).

As is well known, the needle roller bearing (24) does not move along the entire circumference of the trunnion in a universal joint environment. For example, as can be seen from Fig. 6, the needle bearing (24) U in this case moves from the position shown at (34) to the position shown at (36), and then returns to (34) after a swinging motion. Bearing (24) [moves only on a highly localized surface portion of the trunnion α→. Because of this movement, if the contacting surfaces are smooth, for example if they are precisely ground, the lubricant (38) will move between (34) and (36''). on the other hand, in the environment of most anti-friction roller bearings. The roller (24) is the trunnion 04
The lubricant wave (38) is in continuous motion around the circular trunnion α→. As a result, smooth ground surfaces in most anti-friction roller bearing environments are not prone to localized oil starvation problems.

Since this invention relates to proper lubrication under rocking or oscillatory motion, preferred embodiments of the invention are shown in FIGS. 2 and 3. The lands (30) form the roller contact surfaces for the needle bearing, and the valley lands (30) and grooves.

(32) U) Oriented in a thousand yen J approximately perpendicular to the axis of the lanion (14). In Figure 2, the lands (30) and groups (32) each form an annular passage around the body of the cylindrical trunnion. However, in the third position, the lands and grooves are on a helical path around the cylindrical trunnion α→.

In each case, for this land and group, the valley lands are equidistant from the next adjacent land, and each group is equidistant from the next adjacent group.

As seen in the off-figure, the lubrication of the contact area between the trunnion α→ and the needle bearing (24) is caused by the group (32)
By adding , the swing points between (34) and (36) are significantly improved. For off-diagrams, lubricant (38)
is not swept away from the contact path extending between points (34) and (36), but is instead retained within the group (32) between these points. The depth of the group (32) is represented by the space between the bottom of the group (32), indicated by the arc (40), and the top of the land (30), indicated by the arc (42). In contrast, in the conventional interface shown in Figure 6, the smoothly ground cylindrical contact area between the trunnion α→ and the roller (24) is replaced by the smoothly ground contact arc (41) of the trunnion α→. There is no tendency for lubricant to flow out of the contact path between points (34) and (36) along the line.

The preferred method for forming the lands (30) and groups (32) in the trunnion requires only rough machining of the trunnion and subsequent heat treatment, without the need for intermediate or final grinding and/or polishing steps. be. The cross member is typically a metal forging, but may alternatively be a metal casting, as is well known. Machining is 400 to 600
It is preferable to carry out the cutting at a cutting speed within the range of rpm. The feed rate of machine tools is 15/1,000 to 20/1 per revolution,
A range of 000 inches is good. Also, the suitable depth is 60/1
,000 to 90/1,000 inches.

If machining is carried out at the above feed rate and cutting depth,
A roughened surface is effectively achieved on typical metal trunnion members. In the helical case shown in FIG. 3, such surfaces are obtained by continuous tool contact along the entire longitudinal axis of the trunnion body. ° These preferred machining parameters are characterized by the fact that the tool forms lands (30) and groups (32) in a partially and randomly discontinuous manner around the circumference of each trunnion, at any time. In this way, the appearance shown in FIG. 8 is obtained. However, the discontinuities thus created do not destroy the improved lubrication performance of the present invention. For this 9th point, as mentioned in Figure 5, it should be 5/1,000 to 10/1,000 as much as possible.
The optional roll punching step may be performed using rolling members that sink into the lands to a surface depth within the inch degree centigrade range.

A preferred heat treatment step is about 1650°F to 17°F.
Mention may be made of subjecting the trunnion to four-char in a nitrogen atmosphere at a temperature of 50° F. and then quenching the trunnion in oil.

The invention described above provides a significantly improved lubrication mechanism for a trunnion for a universal joint and its associated needle roller bearing.

Also, although various modifications may be made to the embodiments described above, advantages other than retaining oil in the surface area of the trunnion are contemplated. For example, the annular group will also retain corrosion and other debris particles from the mating surfaces. This can also be formed on the cylindrical inner surface of the bearing race (22) as an alternative to reduce the detrimental effects caused by the presence of such particles along the contact interface of the rolling member.

[Brief explanation of the drawing]

FIG. 1 is a partially cut-away plan view of a cross member of a universal joint including the improved trunnion of the present invention, also showing the associated needle bearing and bearing race. FIG. 2 is a partial view of a preferred embodiment of the trunnion of the present invention, FIG. 3 is a partial view of another preferred embodiment of the trunnion of the present invention, and FIG. 4 is a cross section of a group and land of the preferred embodiment of the trunnion. figure,
FIG. 5 is a cross-sectional view of the groups and lands of another preferred embodiment of the same trunnion, FIG. 6 is a partial cross-sectional view of the trunnion-needle bearing interface of a conventional universal joint, and the off view is a cross-sectional view of the improved trunnion of the present invention. 6 is a partial cross-sectional view of the same interface as in FIG. 6 of a universal joint with A preferred embodiment is shown in which discontinuous arrangement is made. 8... Bearing cavity, lO... Cross member, 12... Center body portion, 14... Trunnion, 16... Needle roller bearing, 18... End of 14, 20... Thrust Surface, 22... Bearing race, 24... Needle roller bearing, 26... Friction ring, n... Bottom of 32, 28
...Sealing member, 4...32 protrusion, nod...14
Land, 32...Group of 14, 34-36...
Oscillation range, lubricant (oil wave), 40... arc (32
bottom of ), 41...14 contact arc, 42... arc (3
top of 0). FIG.

Claims (1)

Claims: (1) A journal cross member with radially extending cylindrical trunnions having a longitudinal axis and forming an annular cavity to receive one of the trunnions. In a universal joint comprising a pair of rotating members constituting a pivotably received bifurcated member and a plurality of needle roller bearings disposed between the bifurcated member and each tranio/ a plurality of spaced lands and lubrication groups disposed along the periphery around each trunnion, said group being arranged for rolling communication with said set of bearings of said needle roller bearing lubrication reservoir; forming a rolling contact surface for the bearing, the groups and lands being oriented in a plane substantially perpendicular to the longitudinal axis of the respective trunnion. (2) Each land is equidistant from the next adjacent land,
Universal joint according to claim 1, in which each group is equidistant from the next adjacent group. (3) Claims in which a plurality of lands and groups are arranged in a helical path around each cylindrical trunnion (
2) The universal joint described in 2). (4) Each land and group forms a respective annular passage around each cylindrical trunnion (
2) The universal joint described in 2). (5) The universal joint according to claim 13+ or (4), wherein the groups and lands are partially and randomly discontinuous around the periphery of each trunnion. (6) forming a radially extending cylindrical trunnion disposed in conjunction with the bifurcated members of the pair of rotating members, the trunnion having a plurality of radially spaced lands and groups disposed about the periphery thereof; A cross member for a universal joint that has a . (7) Claims in which a plurality of lands and groups are each equidistant from the next adjacent land and group (6
) The cross member described in ). (8) Claim (7) in which each land and group is arranged on a helical path around each cylindrical trunnion.
The cross member described in. 2°(9) Claims in which lands and groups form respective annular passages around a cylindrical trunnion (
The cross member described in 7). GO) The cross member for a universal joint according to claim 8 or 9, wherein the lands and groups are partially and randomly discontinuous around the periphery of each trunnion. ■ Forming a radially extending cylindrical trunnion arranged in conjunction with the forks of a pair of rotating members, the trunnion having a plurality of radially spaced lands and groups arranged around the periphery; A method of manufacturing a universal joint or a cross member having a trunnion, the method includes the steps of (a) machining lands and groups on the trunnion;
(b) A manufacturing method including the step of heat treating the trunnion. (6) The manufacturing method according to claim αD, characterized by the step of performing roll burnishing on the trunnion niland before the step of heat treating the trunnion. 03) Machining step at a cutting speed of 400 to 600 rpm and 15/1,000 to 20/1 per rotation.
Claim α1) carried out at a feed rate of 000 inches
Or the manufacturing method according to any one of (6). 04 Cutting depth by mechanical machining was 6071,000
and 90/1,000 inches, and the roll burnishing step is carried out by a rotating member that sinks into the land at a surface depth in the range of 571,000 to 10/1,000 inches. manufacturing method. αυ 1650°F' to 1750°F during heat treatment step
The manufacturing method according to claim α→, which comprises charring the trunnion in an atmosphere of nitrogen gas at a temperature within the range of 100 mL, and then quenching the trunnion in oil. 1. A member for a universal joint having an i number of alternatingly spaced lands and croup arranged approximately at right angles to the axis of the joint. A finishing method that includes (a) the step of rough machining the bearing surface and (b) the step of finishing this rough machined surface by heat treatment.Q81 Roll burnishing of the bearing surface prior to the heat treatment step. The finishing method according to claim .alpha., further comprising an additional step of machining the machining step at a cutting speed in the range of 400 to 600 rpm and 15/1,000 to 20 rpm per rotation. The finishing method according to any of claims αn or 081, carried out at a feed rate within the range of /1,000 inches. t2Q Machining within the range of 60/1,000 to 90/1,000 inches. A finishing method according to claim 0&, characterized in that the cutting depth and the roll burnishing step are each carried out by means of a rolling member that sinks into the surface to a depth of 571,000 to 10/1,000 inches. 21) 1650 c'F"fi L 1750
￥ 4 on the surface in a nitrogen gas atmosphere at a temperature within the range of 4.
A finishing method as claimed in claim 1, wherein the heat treatment step includes charcoalizing and then quenching the surface in oil.