CN206694521U - Bearing-like reducer - Google Patents

Abstract

The utility model discloses the Bearing-like reducer in mechanical transmission fields, including shell, retainer, eccentric wheel, bearing plate, shell is fixed on bearing plate, retainer is between shell and bearing plate, the top of retainer is along the circumferential direction uniformly placed with some interior row's ball/posts, and eccentric wheel is connected with interior row's ball/post；Retainer lateral wall is provided with some necks, and outer row's ball/post is provided with neck；The cross section contour of housing interior side-wall is the ripple wire class circular orbit for surrounding circle, and outer row's ball/post is in rolling contact with housing interior side-wall；The middle part outwardly convex of retainer, it is slidably connected between shell and bearing plate in the middle part of retainer, the bottom of retainer is provided with some connecting holes.This programme realizes that the rotating speed of input shaft slows down by the precision-fit between eccentric wheel, ball, race ring and corrugated contours line class circular orbit, and running noise is small, and generation heat is small, and abrasion is small, and gearratio is big, is more suitable for the accurate deceleration transmission of industrial robot.

Description

Bearing-like reducer

Technical field

It the utility model is related to mechanical transmission fields, and in particular to a kind of Bearing-like reducer.

Background technology

The reductor applied to robot field mainly has two kinds at present, and one kind is that Japanese Nabtesco Supreme Being people essence machine is public The Rotate Vector decelerators of department（Abbreviation RV decelerators）, another kind is Japanese Harmonic Drive harmonic speed reducer, They have almost monopolized the robot decelerator in the whole world.In joint of robot, because RV decelerators have higher rigidity And rotating accuracy, RV decelerators are typically placed on the heavy duty position such as support, large arm, shoulder, and harmonic speed reducer is put Put in forearm, wrist or hand.

The transmission of harmonic speed reducer is to realize that transformation of speed and power pass by the elastomeric radial of thin wall flexible gear Pass, thin wall flexible gear capacity and transmission stiffness are relatively low, while flexible gear also easily occurs because of cyclic deformation Fatigue damage, therefore the precision transmission system in being mainly used in, gently loaded, it is multi-purpose make industrial robot wrist, the precision of hand subtracts Speed transmission.

RV decelerators are combined by the transmission of one-level involute cylindrical planetary gear and one-level cycloid pinwheel planetary gear transmission system. The characteristics of in structure design is：After power is inputted by driver pinion, three are driven to turn by the uniform planetary gear of three circumferences Synchronously driving two panels is staggered the Cycloidal Wheels of 180 degree of bias cloth positions arm, and multiple tooth difference is formed between Cycloidal Wheel and pin tooth and is engaged, generation Output torque exported by rotating speed output mechanism.RV decelerators have that compact-sized, gearratio is big, bearing capacity is strong and passed Many advantages, such as dynamic stiffness is high.However, RV basic structure still has defect.On the one hand, due to being passed using involute gear It is dynamic, usually because contact tooth is few, flank of tooth active force is big and the reasons such as flank of tooth relative sliding velocity is big and produce tooth face agglutination, make Tooth form abrasion, cause to engage bad, there is excess fretting wear between tooth form, the problems such as producing noise and heating；On the other hand, by Engaged in Cycloidal Wheel with pin tooth using multiple tooth difference, although more under monodentate difference engagement situation compared with total number of teeth in engagement, not yet Reach full engagement, cause gap in the middle part of engagement process between minute hand tooth and Cycloidal Wheel profile be present, engagement hour hands tooth and pendulum Sliding friction is also easy to produce between line wheel, more serious abrasion can be caused to pin tooth and Cycloidal Wheel after long-term operating, produce noise and Fever phenomenon, decelerator failure is caused to be scrapped when serious.

To sum up, the existing reductor applied to robot field has that bearing capacity is low, and transmission stiffness is low more, and noise is big, The problems such as easily generating heat.

Utility model content

The utility model is intended to provide Bearing-like reducer, to solve the problems, such as that existing decelerator noise is big.

To reach above-mentioned purpose, basic technology scheme of the present utility model is as follows：Bearing-like reducer, including shell, holding Frame, input shaft and bearing plate, input shaft are connected with eccentric wheel, and the top of retainer is rounded to be uniformly placed with some interior row's rollings Pearl/post, the wheel face of eccentric wheel offset with interior row's ball/post；Retainer lateral wall is provided with some circumferentially equally distributed guarantors Plate is held, outer row's ball/post is provided between adjacent holding plate, race ring is provided between interior row's ball/post and outer row ball/post；Outside Shell madial wall is provided with some slots, and the cross section of slot is arc, arc transition between adjacent slots, and each outer row's ball/ Post is in rolling contact with housing interior side-wall.

During this programme practical application, the supporting construction of shell and bearing plate as body contours, shell and retainer are made For the main body supporting structure of reducing gear, holding plate can externally arrange ball/post and carry out positioning and spacing, prevent outer row's ball/ Post activity causes transmission failure, while stable support is provided for retainer and ball/post；Input shaft and eccentric wheel are as power Input, interior row's ball/post and outer row ball/post as power transmission unit, race ring as reduction of speed guard member, outer row's ball/ The quantity of post is more than the quantity of slot on housing interior side-wall, forms what is engaged entirely between housing interior side-wall and outer row's ball/post Movable tooth drive mechanism.

Input shaft is driven by external force, and the eccentric wheel on input shaft follows input shaft to rotate, and eccentric wheel wheel face rolls with interior row Friction between pearl/post arranges ball/post rotation in driving.Interior row's ball/post is in rolling contact with race ring, friction between the two Power rotates interior row's ball/post rotational band dynamic bearing circle, is in rolling contact between race ring and outer row ball/post, between the two Frictional force makes race ring rotate the outer row's ball of drive/post rotation, and race ring is arranged to enter between ball/post and outer row ball/post inside Row reduction of speed transmission, prevent interior row's ball/post from directly being contacted with outer row's ball/post, both high-speed frictions produce heating, ablation, mill The problems such as damage；Shell is fixed, and outer row's ball/post rolls on wall inside the shell while rotation, is set on housing interior side-wall There is the slot of arc transition, eccentric wheel, which rotates, causes interior row's ball/post, race ring and outer row ball/post to be extruded by bias, Rolled inside the shell between the slot on wall all the time so that arranging ball/post outside, outer row's ball/post when rolling by slot it Between arc surface stop, when eccentric wheel, which rotates, pushes outer row's ball/post, its circumferential rotatory force overcomes outer row's ball/post The resistance of arc surface, which rolls, to advance, and due to the quantity of the slot count and outer row's ball/post of shell, outer row's ball/post is simultaneously Contacted with housing interior side-wall, holding plate, race ring, therefore, outer row's ball/post produces circumferential mistake when being engaged with housing interior side-wall Tooth moves, and the extruding of outer row's ball/post promotes holding plate, makes holding plate promote retainer to rotate, and the rotation of input shaft passes through above-mentioned It is changed into the rotation of retainer after transmission, is realized during this by outer row's ball/transmission between post and housing interior side-wall The deceleration of power transmission.

The eccentric wheel, multistage Ball Transmission, some sections that this programme passes through circle are the mutual arc transition of slot of arc The Oscillating Tooth Gear Reducer structure that the class circular orbit composition of formation engages entirely, all the time in tight between ball and class circular orbit and eccentric wheel The tactile state of contiguity, mismatch error is small, and larger abrasion and noise will not be produced during use, and eccentric wheel is all when rotating Outer row's ball/post contacts to form full engagement with class circular orbit, and radial load is divided equally by outer row's ball/post and interior row ball/post, Internal stress equalization is avoided unbalance stress generation sliding friction and cause abrasion and noise；Made using ball in transmission process It is rolling friction between portion's part, fatigue failure caused by the glued phenomenon of tooth is not present in the tooth form engagement compared to prior art And wear-out defect, the abrasion of inner body is small, and service life is longer；Eccentric wheel input speed passes through interior row's ball/post, bearing The multistage decreasing transmission of circle, outer row ball/between post and shell, each ball/post both participate in deceleration transmission, and eccentric wheel rotates Multi-turn can just drive outer row's ball/post to promote retainer to turn an angle after being acted on shell so that gearratio is big；Holding plate The position of outer row's ball/post is limited, reduces the activity space of inside, while by close with outer row's ball/post, race ring etc. Contact make structure it is compacter, without stress weak link, strengthen the mechanical property of retainer, enable Bearing-like reducer bear compared with High load.To sum up, the utility model forms Oscillating Tooth Gear Reducer by interior row's ball/post, race ring, outer row ball/post and shell Structure, using full engagement pure rolling transmission, noise and the abrasion between inner body can be effectively reduced, have that noise is small, transmission Than the features such as big, service life is long, compact-sized, it is skillfully constructed, structure is novel, is more suitable for practicality compared to prior art.

Preferred scheme one, based on scheme a kind of improvement, the inwall of race ring offsets with interior row's ball/post, bearing The outer wall of circle offsets with outer row's ball/post.So connect between race ring and interior row ball/post and outer row ball/post and more may be used By stable, effectively power can be sent to outer row's ball/post by race ring when row's ball/post rotates in guarantee, and set Put race ring and be avoided that interior row's ball/post directly contacts with outer row's ball/post, prevent Relative friction violent between the two from producing Noise or high temperature cause ablation, operate Bearing-like reducer more reliable and more stable, service life is longer.

A kind of improvement of preferred scheme two, preferably one, input is fixed with the input shaft of eccentric wheel upper end Bearing, is fixed with lower input shaft bearing on the input shaft of eccentric wheel lower end, the inwardly protruding formation spacing ring in middle part of retainer inwall, Lower input shaft bearing is placed on spacing ring upper end.Input shaft bearing and lower input shaft bearing can carry out spacing centering to input shaft in setting And guiding, make input shaft more stable, set spacing ring to be easy to that lower input shaft bearing is mounted so that positioning assembling is more It is simple easy to add.

A kind of improvement of preferred scheme three, preferably two, the shell include circular side plate, side plate inwall Top extend inwardly to form annular shape upper head plate, the bottom of side plate outer wall stretch out to be formed annular shape bottom plate, under End plate is fixedly connected on bearing plate, and slot is located on the madial wall of upper head plate, all outer row's ball/posts with upper head plate Side wall is in rolling contact.Bottom plate is so set to be easy to carry out location and installation to shell, upper head plate and side plate are easy to enter retainer Row is spacing and protection, the madial wall of upper head plate set slot make it that the cross section contour of madial wall is the ripple close to cycloid shape The class circular orbit that line surrounds, outer row's ball/post move under the pushing of eccentric wheel along class circular orbit so that outside Bearing-like reducer Shell is vdiverse in function, reduces inner body, and integration degree is high, reduces complex degree of structure, reduces error band when more parts coordinate The influence come.

A kind of improvement of preferred scheme four, preferably two, the retainer include what is set gradually from top to bottom Input ring, mounting ring and output ring, the lateral wall for inputting ring is provided with some necks, neck be located at two neighboring holding plate it Between, the mounting ring is slidably connected between shell and bearing plate, and the bottom of output ring is provided with some equally distributed connections Hole.So power input bearing structure of the setting input ring as retainer, installation and positioning structure of the mounting ring as retainer, Power output structure of the output ring as retainer, it is power output to set delivery outlet to be used for the conversion of motion of retainer；If Spacing and protection can be provided for outer row's ball/post by putting neck, and outer row's ball/post intermittence is by interior during retainer use The extruding of ball/post and centre wheel housing is arranged, certain buffer gap can be provided for outer row's ball/post by neck, make outer row Ball/post can carry out elastic movement between adjacent holding plate, reduce outer row's ball/post and holding plate, interior row ball/post, Abrasion that larger sliding friction caused by rigidly being extruded between centre wheel housing is brought, the harmful effect such as noise；So that retainer Structure it is more reasonable, be more uniformly stressed, service life is longer.

A kind of improvement of preferred scheme five, preferably four, sets between the top of mounting ring and the bottom of upper head plate There is upper plain thrust bearing, lower plane thrust bearing is provided between the bottom of mounting ring and the top of bearing plate.By upper and lower Plain thrust bearing causes the upper and lower end of mounting ring to be contacted respectively between shell, bearing plate for rolling friction, mounting ring with Frictional resistance between side wall of outer shell is smaller, and the abrasion during use to mounting ring is small, and the rotation of retainer is more smooth, no Obvious noise can be produced.

A kind of improvement of preferred scheme six, preferably five, the upper end of the bearing plate are provided with the convex of annular shape Rib, the external diameter of fin is identical with the internal diameter of shell side plate, and the external diameter of lower plane thrust bearing is identical with the internal diameter of fin, output ring External diameter it is identical with the internal diameter of bearing plate.Set fin on the one hand can strengthen the intensity and non-deformability of bearing plate, separately On the one hand lower plane thrust bearing can be carried out positioning and spacing, makes the positioning of lower plane thrust bearing more accurate, operate more It is stable, make reductor operating more smooth.

A kind of improvement of preferred scheme seven, preferably two, the lateral wall of mounting ring and the madial wall of shell side plate Between be provided with output support ball/post.Set output support ball/post to carry out the outside of mounting ring spacing, while make installation Contacted between ring lateral wall and shell side plate for rolling friction, the frictional resistance between mounting ring and side wall of outer shell is smaller, uses During abrasion to mounting ring it is small, the rotation of retainer is more smooth, will not produce obvious noise.

Preferred scheme eight, based on scheme improve to a kind of any of preferred scheme seven, the top spiral shell of shell upper head plate Tethering and be connected to cover plate, the middle part of cover plate is provided with input hole, and input hole is arranged concentrically with input shaft, and the bottom of cover plate is stepped, The bottom of cover plate respectively with upper input shaft bearing, interior row ball/post, race ring, outer row ball/post, holding plate and shell top Offset.Set cover plate to block the bearing inside reductor, ball/post, prevent introduced contaminants, dust etc. from entering reductor Inside, avoid reductor inner inclusion impurity, dust influence reductor parts between transmission accuracy, reduce parts between Abrasion, further reduce noise.

Brief description of the drawings

Fig. 1 is the structural representation of the utility model embodiment；

Fig. 2 is the structural representation of retainer in the utility model embodiment；

Fig. 3 is the structural representation of shell in the utility model embodiment.

Embodiment

The utility model is described in further detail below by embodiment：

Reference in Figure of description includes：Bearing plate 1, fin 11, retainer 2, holding plate 21, interior row's roller 22nd, outer row's roller 23, input ring 24, mounting ring 25, output ring 26, neck 27, spacing ring 28, connecting hole 29, shell 3, upper flat Face thrust bearing 31, output supporting roller 32, lower plane thrust bearing 33, upper head plate 34, annular protrusion 341, side plate 35, groove 351st, bottom plate 36, slot 37, mounting hole 38, pilot hole 39, cover plate 4, eccentric wheel 5, upper input shaft bearing 51, lower input shaft bearing 52nd, race ring 6.

Embodiment is substantially as shown in Figure 1：Bearing-like reducer, including shell 3, retainer 2, input shaft, bearing plate 1, Shell 3 is fixedly connected on bearing plate 1 by screw, and retainer 2 is between shell 3 and bearing plate 1, one on input shaft Body formed to have circular eccentric wheel 5, being interference fitted on the input shaft of the top of eccentric wheel 5 has upper input shaft bearing 51, under eccentric cam Interference fit has lower input shaft bearing 52 on the input shaft of side.As shown in Fig. 2 retainer 2 includes integrally formed circular sheet Body, body include input ring 24, mounting ring 25 and the output ring 26 being sequentially distributed from top to bottom, input the top of ring 24 circumferentially Direction is uniformly placed with some interior row's rollers 22, and the bottom outwardly convex for inputting the inwall of ring 24 forms spacing ring 28, input shaft card It is connected on retainer 2, lower input shaft bearing 52 is connected to the top of spacing ring 28, and upper input shaft bearing 51 is located at the top of retainer 2, eccentric The wheel face of wheel 5 offsets with all interior row's rollers 22；The lateral wall of input ring 24 is provided with some circumferentially equally distributed cards Groove 27, integrally formed with holding plate 21 on the lateral wall of input ring 24 between adjacent neck 27, outer row's roller is provided with neck 27 23, each outer row's roller 23 is connected between two neighboring holding plate 21；The outside of interior row's roller 22 is provided with race ring 6, axle Circle 6 is held between interior row's roller 22 and outer row's roller 23, the inwall of race ring 6 offsets with all interior row's rollers 22, bearing The outer wall of circle 6 offsets with all outer row's rollers 23, interior row's roller 22, race ring 6, the upper end of outer row's roller 23 and holding plate 21 Flush.As shown in figure 3, shell 3 includes circular side plate 35, the top of the inwall of side plate 35 extends inwardly to form the upper of annular shape End plate 34, the bottom of the outer wall of side plate 35 stretch out to form the bottom plate 36 of annular shape, and the madial wall of upper head plate 34 is provided with Some sections are the slot 37 of arc, use arc transition between two neighboring slot 37 so that the madial wall of upper head plate 34 is Waveform, madial wall of all outer row's rollers 23 with upper head plate 34 offset, and form the similar contact relation engaged entirely, outer row's rolling The quantity of post 23 than slot 37 quantity more than one；The bottom of upper head plate 34 is provided with annular protrusion 341, the bottom of the inwall of side plate 35 Groove 351 provided with ring-type.Bearing plate 1 is annular shape, and the upper end of bearing plate 1 is provided with circular fin 11, fin 11 External diameter it is identical with the internal diameter of the side plate 35 of shell 3, the external diameter of bearing plate 1 is identical with the external diameter of the bottom plate 36 of shell 3, bottom plate 36 are provided with pilot hole 39, and bottom plate 36 is fixedly connected on to the upper end of bearing plate 1 at pilot hole 39 by screw.Installation Ring 25 is between upper head plate 34 and bearing plate 1, and interference fit has upper flat between the top of mounting ring 25 and annular protrusion 341 Face thrust bearing 31, interference fit has lower plane thrust bearing 33 between the bottom of mounting ring 25 and the top of bearing plate 1, under The external diameter of plain thrust bearing 33 is identical with the internal diameter of fin 11；It is interference fitted between the lateral wall and groove 351 of mounting ring 25 There is output supporting roller 32.Output ring 26 is located at the inner side of bearing plate 1, and the bottom of output ring 26 is provided with some connecting holes 29. The top of the upper head plate 34 of shell 3 is provided with mounting hole 38, and the inner bolt of mounting hole 38 is connected with cover plate 4, and the middle part of cover plate 4 is provided with input Hole, input hole are arranged concentrically with input shaft, and the bottom of cover plate 4 is stepped, the bottom of cover plate 4 respectively with upper input shaft bearing 51, Interior row's roller 22, race ring 6, outer row's roller 23, the top of holding plate 21 and the upper head plate 34 of shell 3 offset.

In the present embodiment, during practical application, Bearing-like reducer is fixedly mounted by bolt for bearing plate 1, exterior power Rotate input shaft, input shaft rotational band movable eccentric wheel 5 rotates, and the friction between eccentric wheel 5 and interior row's roller 22 rolls interior row Post 22 rotates, and realization delivers power to interior row's roller 22, and interior row's roller 22 is by the frictional force between race ring 6 by power Race ring 6 is transferred to, race ring 6 delivers power to outer row's roller 23 by the frictional force between outer row's roller 23, makes outer Arrange roller 23 to rotate in the neck 27, during this between eccentric wheel 5 and interior row's roller 22, interior row's roller 22 and race ring 6 Between, be in close contact between race ring 6 and outer row's roller 23, be between each other stable rolling friction, while arrange roller outside 23 roll under the contact relation engaged entirely similar with the madial wall of upper head plate 34 by track of the medial side wall profiles of upper head plate 34, Holding plate 21 is promoted to rotate retainer 2 during rolling, output ring 26 rotates output power.Upper and lower plain thrust bearing 33 and output supporting roller 32 mounting ring 25 is carried out it is spacing.Motor is by input shaft input power, the eccentric wheel 5 on input shaft Friction between wheel face and interior row's roller 22 drives interior row's roller 22 to rotate.Interior row's roller 22 is in rolling contact with race ring 6, both Between frictional force rotate the interior rotational band dynamic bearing circle 6 of row's roller 22, be in rolling contact between race ring 6 and outer row's roller 23, Frictional force between the two makes the rotation of race ring 6 drive outer row's roller 23 to rotate, row's roller 22 and outer row's roller including race ring 6 Reduction of speed transmission is carried out between 23, outer row's roller 23 rolls while rotation on the inwall of shell 3, and the madial wall of shell 3 is provided with circle The slot 37 of arc transition, eccentric wheel 5, which rotates, causes interior row's roller 22, race ring 6 and outer row's roller 23 to be extruded by bias, makes Outer row's roller 23 is rolled between the slot 37 on the madial wall of shell 3 all the time, outer row's roller 23 is when rolling by slot 37 Between arc surface stop, when eccentric wheel 5, which rotates, pushes outer row's roller 23, before outer row's roller 23 is overcome the resistance of arc surface Enter, due to the quantity of the quantity of slot 37 and the outer row's roller 23 of shell 3, outer row's roller 23 simultaneously with slot 37, holding plate 21st, race ring 6 contacts, and by the frictional force from different directions, therefore, outer row's roller 23 produces week when being engaged with slot 37 Moved to side set, the outer extruding of row's roller 23 promotes holding plate 21 to move, and rotates retainer 2, rotation direction rotates with input shaft In the opposite direction, the rotation rotated by being changed into retainer 2 after above-mentioned transmission of input shaft, realize that power transmits during this Deceleration.

Above-described is only embodiment of the present utility model, the general knowledge such as known concrete structure and/or characteristic in scheme Do not describe excessively herein.It should be pointed out that for those skilled in the art, before the utility model structure is not departed from Put, several modifications and improvements can also be made, these should also be considered as the scope of protection of the utility model, and these are all without shadow Ring effect and practical applicability that the utility model is implemented.This application claims protection domain should be with its claim Appearance is defined, and the record such as embodiment in specification can be used for the content for explaining claim.

Claims (9)

1. Bearing-like reducer, it is characterised in that including shell, retainer, input shaft and bearing plate, input shaft is connected with bias Wheel, the top of retainer is rounded to be uniformly placed with some interior row's ball/posts, and the wheel face of eccentric wheel offsets with interior row's ball/post； Some holding plates are evenly distributed with retainer lateral wall, outer row's ball/post, interior row's ball/post are provided between adjacent holding plate Race ring is provided between outer row's ball/post；Housing interior side-wall is provided with some slots, and the cross section of slot is arc, adjacent Arc transition between slot, each outer row's ball/post are in rolling contact with housing interior side-wall.

2. Bearing-like reducer according to claim 1, it is characterised in that：The inwall of the race ring and interior row's ball/post Offset, the outer wall of race ring offsets with outer row's ball/post.

3. Bearing-like reducer according to claim 2, it is characterised in that：It is fixed with the input shaft of eccentric wheel upper end defeated Enter bearing, lower input shaft bearing is fixed with the input shaft of eccentric wheel lower end, the inwardly protruding formation in middle part of retainer inwall is spacing Ring, lower input shaft bearing are placed on spacing ring upper end.

4. Bearing-like reducer according to claim 3, it is characterised in that：The shell includes circular side plate, side plate The top of inwall extends inwardly to form the upper head plate of annular shape, and the bottom of side plate outer wall stretches out to form the lower end of annular shape Plate, bottom plate are fixedly connected on bearing plate, and the slot is located on the madial wall of upper head plate, and all outer row's ball/posts are equal It is in rolling contact with upper head plate madial wall.

5. Bearing-like reducer according to claim 3, it is characterised in that：The retainer includes setting gradually from top to bottom Input ring, mounting ring and output ring, the lateral wall for inputting ring is provided with some necks, neck be located at two neighboring holding plate it Between, the mounting ring is slidably connected between shell and bearing plate, and the bottom of output ring is provided with some equally distributed connections Hole.

6. Bearing-like reducer according to claim 5, it is characterised in that：Between the top of mounting ring and the bottom of upper head plate Provided with upper plain thrust bearing, lower plane thrust bearing is provided between the bottom of mounting ring and the top of bearing plate.

7. Bearing-like reducer according to claim 6, it is characterised in that：The upper end of the bearing plate is provided with circular Fin, the external diameter of fin is identical with the internal diameter of shell side plate, and the external diameter of lower plane thrust bearing is identical with the internal diameter of fin, output The external diameter of ring is identical with the internal diameter of bearing plate.

8. Bearing-like reducer according to claim 7, it is characterised in that：The lateral wall of mounting ring and the inner side of shell side plate Output support ball/post is provided between wall.

9. Bearing-like reducer according to any one of claims 1 to 8, it is characterised in that：The top bolt of shell upper head plate connects Cover plate is connected to, the middle part of cover plate is provided with input hole, and input hole is arranged concentrically with input shaft, and the bottom of cover plate is stepped, cover plate Bottom respectively with being offseted at the top of upper input shaft bearing, interior row ball/post, race ring, outer row ball/post, holding plate and shell.