JP5668420B2 - Tapered roller bearing and method for manufacturing cage for tapered roller bearing - Google Patents

Description

  The present invention supports various rotating shafts that rotate in a state where a large radial load and thrust load are applied, such as a transmission shaft that constitutes an axle of a railway vehicle and a drive shaft, or a pinion shaft that constitutes a differential gear for an automobile. The present invention relates to an improved tapered roller bearing and a method of manufacturing a cage incorporated in the tapered roller bearing. Specifically, with regard to the invention of the tapered roller bearing, the durability in a poorly lubricated state is devised by devising the shape and structure of the cage that holds the plurality of tapered rollers constituting the tapered roller bearing in a freely rolling manner. It is intended to improve, i.e., to extend the time from the occurrence of poor lubrication to the inability to rotate due to seizure. Further, with respect to the method for manufacturing the tapered roller bearing retainer, the above-described retainer can be manufactured industrially efficiently.

  For example, a tapered roller bearing 1 as shown in FIG. 16 is incorporated in a rotation support portion for a rotating shaft that rotates while supporting a large radial load and thrust load, such as a pinion shaft of a differential gear. The tapered roller bearing 1 includes an outer ring 2 and an inner ring 3 that are arranged concentrically with each other, a plurality of tapered rollers 4 and 4, and a cage 5. Out of these, the outer ring 2 has a concave outer ring raceway 6 on the inner peripheral surface. The inner ring 3 is disposed on the inner diameter side of the outer ring 2 and has a partially conical convex inner ring raceway 7 on the outer peripheral surface. Further, a large-diameter side collar 8 is formed at the large-diameter end of the outer peripheral surface of the inner ring 3, and a small-diameter collar 9 is formed at the small-diameter end, respectively. It is formed in a protruding state. The tapered rollers 4, 4 are arranged so as to roll freely between the outer ring raceway 6 and the inner ring raceway 7, and the large-diameter side end surfaces (heads) 10 are respectively connected to the large ring ends 4. It is made to oppose with the axial inner surface 11 of the diameter side collar part 8. FIG. The cage 5 is for holding the tapered rollers 4 and 4.

  The cage 5 is arranged concentrically and spaced apart in the axial direction, and has a large-diameter side rim portion 12 and a small-diameter side rim portion 13 each having an annular shape, and both the rim portions 12, 13. A plurality of pillars 14 and 14 are provided between the two. And in order to hold | maintain each said tapered roller 4 and 4 so that rolling is possible, respectively, the part enclosed by these two rim | limb parts 12 and 13 and a pair of pillar parts 14 and 14 which adjoin each other in the circumferential direction. Pockets 15 and 15. Note that the cage 5 shown in FIG. 16 is formed by bending a metal plate, and by forming a bent plate portion 16 having an inward flange shape that is bent radially inward from the end portion on the small diameter side, The overall rigidity is secured.

  17 to 19 show a tapered roller bearing 1 incorporating a cage 5a having a different shape as a second example of a conventionally known tapered roller bearing. The cage 5a is integrally formed by injection molding a synthetic resin or by machining a metal material. The basic structure is similar to the cage 5 incorporated in the first example of the conventional structure shown in FIG. 16 described above, and is arranged on the large-diameter side rims each having an annular shape and spaced apart in the axial direction. Part 12a and a small-diameter side rim part 13a and a plurality of pillar parts 14a, 14a, and the four rims are surrounded by a pair of pillar parts 14a, 14a adjacent to each other in the circumferential direction. The portions are pockets 15a and 15a, respectively. In the case of this example, since both the rim portions 12a and 13a themselves can sufficiently secure rigidity, the bending plate portion 16 (see FIG. 16) like the cage 5 of the first example is not provided. A circular recess 20 is provided at the center of the large-diameter end face 10 of the tapered roller 4a.

  In any structure, when the tapered roller bearing 1 is operated, each of the tapered rollers 4 and 4a is caused by a large radial load applied from the partially tapered concave outer ring raceway 6 and the partially tapered convex inner ring raceway 7. It tends to be displaced to the larger diameter side of the tracks 6 and 7. As a result, during operation of the tapered roller bearing 1, the tapered rollers 4, 4 a are brought into contact with the large-diameter side end face 10 and the large-diameter side flange 8 with the relative rotation of the outer ring 2 and the inner ring 3. It rotates and revolves while making sliding contact with the axially inner side surface 11. In this case, the frictional state between the large-diameter side end face 10 and the axially inner side surface 11 of the large-diameter side flange 8 is almost sliding friction, so that wear resistance and seizure resistance are ensured. From the aspect of doing, it becomes very severe conditions. Therefore, conventionally, sufficient lubrication oil is supplied to the rotation support portion in which the tapered roller bearing 1 as described above is incorporated, so that the axially inner side surfaces of the large-diameter side end surface 10 and the large-diameter side flange portion 8 are supplied. 11 is configured such that a sufficient lubricating oil film is interposed on the sliding surface.

  In the normal state in which a sufficient amount of lubricating oil can be supplied to the rotation support portion in which the tapered roller bearing 1 is incorporated, the tapered roller bearing 1 having the conventional structure as described above does not cause any particular problem. However, regardless of the type of the rotation support device in which the tapered roller bearing 1 is incorporated, the possibility that the lubricating oil supplied to the tapered roller bearing 1 is insufficient or depleted due to some failure or poor maintenance is completely eliminated. You can't deny it. When the lubricating oil supplied to the tapered roller bearing 1 is insufficient or exhausted, first, sliding between the large-diameter side end surface 10 and the axially inner side surface 11 of the large-diameter side flange 8 is the most severe condition. Surface wear proceeds significantly. In a further remarkable case, the large-diameter side end face 10 and the axially inner side face 11 are adhered to each other, so that the tapered rollers 4 and 4a cannot be rotated and revolved. Further, the tapered rollers 4 and 4a The rolling contact surface and the outer ring raceway 6 adhere to each other, and so-called seizure is generated in which relative rotation between the outer ring 2 and the inner ring 3 becomes impossible.

  If such burn-in occurs, it becomes difficult to move the vehicle (railway vehicle or automobile) as well as normal operation of the vehicle, and problems such as delay in restoration of the railroad or traffic congestion are likely to occur. In addition, the inability to rotate the rotation support part causes a failure of other parts, and problems such as cost and time required for repair are likely to occur. As shown in FIG. 23, such a problem has a large contact angle, that is, the center axis of the outer ring raceway 6 formed on the inner peripheral surface of the outer ring 2 and the inner ring raceway 7 formed on the outer peripheral surface of the inner ring 3. In the case of the tapered roller bearing 1 in which the inclination angle between the rotation axis of each tapered roller 4a and the central axis of the outer ring 2 and the inner ring 3 is large, the inclination tends to be remarkable. For example, the tapered roller bearing 1 having a contact angle of 20 degrees or more has a large component force for displacing each tapered roller 4a to the large diameter side based on a large load (radial load and thrust load) applied during use. The surface pressure of the sliding contact portion between the large-diameter end surface 10 of the tapered roller 4a and the axial inner surface 11 of the large-diameter flange 8 formed on the outer peripheral surface of the inner ring 3 is increased. As a result, in a state of poor lubrication, the wear of the sliding contact portions between the both surfaces 10 and 11 tends to be remarkable. In particular, when the contact angle is 25 degrees or more, the tendency becomes remarkable.

  Note that the cage 5f incorporated in the tapered roller bearing 1 having a large contact angle as shown in FIG. 23 described above includes a diameter of the large-diameter side rim portion 12c and a small-diameter side rim as shown in FIGS. The difference with the diameter of the part 13b is large, and the inclination angle of the column parts 14b and 14b spanned between the rim parts 12c and 13b is large. Even when the cage 5f shown in FIGS. 24 to 25 or the cage 5a shown in FIGS. 18 to 19 is made of synthetic resin, the axial direction as shown in FIG. The injection molding is performed by a so-called axial draw using a mold apparatus 24 having a pair of molds 22 and 23 that move far and away from each other. That is, in a state where these molds 22 and 23 are abutted, a thermoplastic synthetic resin is heated and melted in a molding space (cavity) defined between the molds 22 and 23. The pressure is applied through a plurality of inlets called gates. Then, after the synthetic resin is cooled and solidified, the molds 22 and 23 are separated from each other, and the molded cage 5f (5a) is taken out.

Even in the tapered roller bearing 1 using the cages 5, 5 a, 5 f of any structure, as described above, there is a possibility that significant wear and seizure occur.
In view of such circumstances, in Patent Documents 1 and 2, a sliding contact portion between the large-diameter side end surface of each tapered roller and the axially inner side surface of the large-diameter side flange is provided in Patent Documents 1 and 2 effectively. The structure to be lubricated is described. 20 to 22 show two examples of the conventional structure described in Patent Document 1 among them.

  First, in the case of the first example of a known countermeasure structure shown in FIG. 20, this is done by bending the large diameter side end of the metal plate cage 5b inward in the radial direction. An oil retaining portion 17 is provided over the entire circumference at the end on the large diameter side of the inner peripheral surface of the cage 5b. In the first example of this conventional structure, the lubricating oil stored in the oil retaining portion 17 is applied to the sliding contact portion between the large-diameter side end surface 10 of the tapered roller 4 and the axially inner side surface 11 of the large-diameter side flange portion 8. It is intended to suppress wear during poor lubrication.

  Next, in the case of the second example of the known countermeasure structure shown in FIGS. 21 to 22, the cage 5c is bent by outwardly bending the small diameter side end portion of the cage 5c. An oil retaining portion 17a is provided at the end on the small diameter side of the outer peripheral surface of 5c. In addition, the oil retaining portion 17a is divided into a plurality of parts in the circumferential direction by the partition plates 18 and 18. The second example of this conventional structure prevents the lubricating oil from adhering to the outer peripheral surface of the cage 5c and reaching the small diameter end of the cage 5c. This is supplied to the sliding contact portion between the radial side end surface 10 and the axially inner side surface 11 of the large diameter side flange 8 so as to suppress wear during poor lubrication.

  In the case of two examples of countermeasures known from the past as described above, a small amount of lubricating oil can be obtained even though excellent durability can be obtained as compared with the unmeasured structures shown in FIGS. Cannot be efficiently supplied to the sliding contact portion between the large-diameter side end surface 10 and the axially inner side surface 11 (a small amount of lubricating oil can be effectively used). First, in the case of the structure of the first example shown in FIG. 20, the amount of lubricating oil that does not adhere to the large-diameter end face 10 of each tapered roller 4 while remaining in the oil retaining portion 17 increases. It is difficult to effectively use a small amount of lubricating oil. The structure of the second example shown in FIGS. 21 to 22 is also provided because the oil retaining portion 17a is provided in a portion that is greatly separated from the sliding contact portion between the large-diameter side end surface 10 and the axial inner surface 11. It is difficult to effectively use a small amount of lubricating oil for lubricating the sliding contact portion. In this way, a small amount of lubricating oil cannot be effectively used for lubrication of the sliding contact portion between the large-diameter side end surface 10 and the axially inner side surface 11. The same holds true even if the oil retaining portion 17 shown is provided with the partition plate portions 18 and 18 shown in FIG.

  In Patent Document 2, the lubricating oil guided along the inner peripheral surface of the cage is connected to the large-diameter side end surface of the tapered roller by an inward large-diameter side flange provided at the large-diameter side edge of the cage. A structure is described that leads to a sliding contact portion with the inner surface in the axial direction of the large-diameter side flange on the outer peripheral surface of the inner ring. In the case of the third example of the countermeasured structure described in Patent Document 2 as described above, a small amount of lubricating oil is applied to the large-diameter side end face even if superior durability can be obtained compared to the non-measured structure. There is room for improvement in terms of the surface that is efficiently supplied by the sliding contact portion between the inner surface and the axial inner surface.

  In view of the circumstances as described above, the present invention is a structure that can improve the durability in a poorly lubricated state, that is, a structure that can sufficiently extend the time until it becomes non-rotatable due to seizure after being in a poorly lubricated state, And it invented in order to implement | achieve an appropriate manufacturing method in order to obtain the holder | retainer for implement | achieving the said structure.

The tapered roller bearing that is the subject of the present invention includes an outer ring, an inner ring, a plurality of tapered rollers, and a cage, like the conventionally known tapered roller bearing.
Among these, the outer ring has a partially conical concave outer ring raceway on the inner peripheral surface.
Further, the inner ring is disposed concentrically with the outer ring on the inner diameter side of the outer ring. On the outer peripheral surface, a partially conical convex inner ring raceway, and a radial direction from a large diameter side end of the inner ring raceway. It has a large-diameter side flange projecting outward.
Further, each of the tapered rollers is disposed between the inner ring raceway and the outer ring raceway so as to be able to roll, and each large diameter side end face is opposed to the axial side surface of the large diameter side flange. .
The cage is made of a synthetic resin and is used to hold the tapered rollers.
The retainer is arranged concentrically and spaced apart in the axial direction, each having a ring-shaped large-diameter side rim portion and small-diameter side rim portion, and between these rim portions. And a plurality of pillars spanned. And it has the structure which used as the pocket for hold | maintaining each said tapered roller, respectively the part enclosed by the circumference | surroundings by these both rim | limb parts and a pair of pillar parts adjacent to the circumference direction.

In particular, in the tapered roller bearing according to the present invention, in the large-diameter side rim portion, the inner circumferential surface portion of the portion where the phase in the circumferential direction is aligned with each pocket is independent of the circumferential direction. In addition , the same number of oil retaining recesses as the pockets are provided in a state of being recessed radially outward.
Each of these oil retaining recesses has an arc shape in which a cross-sectional shape related to a virtual plane orthogonal to the axial direction of the cage is deepest in the center portion in the width direction in the circumferential direction.
Also, the portion which opens to the inner surface of each pocket of the bottom surface of each Hoyu recess, the large diameter side end face of the tapered roller held in the in each pocket (preferably, in the large-diameter end face It is made to oppose the recessed part formed. However, the concave portion on the end face on the large diameter side can be omitted.
Furthermore, a portion of the inner peripheral surface of the large-diameter side rim portion that is circumferentially disengaged from each oil retaining recess extends over the entire length in the axial direction, and is a cylindrical surface parallel to the central axis of the cage Or it is the inclined surface which inclined in the direction which goes to radial direction outward as it goes to each said pocket.

When implementing such a tapered roller bearing of the present invention, preferably, as in the invention described in claim 2, each of these oil retaining oils is provided on the outer end face side of the large diameter rim portion of each of the oil retaining recesses. A weir is provided that blocks the inside of the recess and the outer end surface of the large-diameter side rim portion (prevents the inside of each oil retaining recess and the outer end surface of the large-diameter side rim portion from penetrating in the axial direction). Specifically, each oil retaining recess is recessed radially outward from the inner peripheral surface of the large-diameter rim portion from the opening-side end portion on the pocket side to the back-end portion on the outer end surface side. Provide depth in the direction of entry. In other words, a step is provided between the back end portion of the bottom surface of each oil retaining recess and the inner peripheral surface of the large diameter rim portion.

Further, when practicing the present invention, preferably, as in the invention described in claim 3, toward the bottom of the oil-retaining recess, radially outward in accordance with the over the entire axial length toward each pocket Tilt in the direction .
In addition, the inner peripheral surface of the oil retaining recess formed in the large-diameter side rim portion can be a cylindrical surface parallel to the central axis of the cage .

Further, when the present invention is carried out, preferably, as in the invention described in claim 4 , the retainer is inserted into the molding space of the mold apparatus in a molten state with a synthetic resin having thermoplasticity. It shall be constructed by sending in a state where pressure is applied through the feeding port. Therefore, in the cage, there is a weld that is generated when a synthetic resin in a molten state, which is fed into the molding space from a different feeding port, abuts in the molding space. In the case of the invention described in the fourth aspect , the weld is present in a portion deviated from a continuous portion between the rim portions and the pillar portions.

When the present invention is carried out, it is preferable that the tapered roller bearing is driven by a self-propelled vehicle (not towed by a tractor or a locomotive, as in the invention described in claim 5). Of a rotary shaft constituting a vehicle drive system that is provided between a drive source and a drive wheel of the vehicle) and that transmits a rotational drive force of the drive source to the drive wheel. Used for support. As a rotating shaft constituting such a vehicle drive system, for example, a pinion shaft constituting a differential gear of an automobile, a power transmission shaft constituting an automobile transmission (including an automatic transmission, a manual transmission, and a transaxle) In addition, a power transmission shaft of a railway vehicle drive unit and the like are included.

According to a sixth aspect of the present invention, there is provided a method of manufacturing a tapered roller bearing as a mold apparatus for injection molding the synthetic resin cage described in the fourth aspect. A feeding port for feeding the resin is provided in each of the rim portion molding space portions for forming the rim portions in the molding space, and the installation positions of the feeding ports are formed in the rim portion molding portions. With respect to the circumferential direction of the space portion for use, those which are made to coincide with each other between the two rim portion forming space portions are used.

Further, in the method for manufacturing a tapered roller bearing according to claim 7, a die device that satisfies all of the following conditions (1) to (3) is used.
(1) An axial draw structure in which a pair of molds arranged concentrically with each other are moved in the axial direction.
(2) A molding concave portion is provided on the axial end surface of one of the axial end surfaces facing each other of the molds, and a molding convex portion is provided on the axial end surface of the other die. Yes.
(3) An oil retaining recess forming convex portion for forming the oil retaining recess is provided on the axial end surface of the one mold.
When carrying out the invention described in claim 7 , preferably, as in the invention described in claim 8 , as the one mold, a step portion is provided at the tip of the oil retaining recess forming convex portion. Use what exists.

The tapered roller bearing of the present invention configured as described above improves the durability in a poorly lubricated state by acting as follows, i.e., from the poorly lubricated state until it becomes non-rotatable due to seizure. The time can be extended more fully.
As in the case of general tapered roller bearings, the lubricating oil during operation of the rotary machine device incorporating the tapered roller bearing of the present invention is a pump based on the centrifugal force associated with the revolving motion of each tapered roller. By the action, the bearing inner space between the inner peripheral surface of the outer ring and the outer peripheral surface of the inner ring flows from the small diameter side to the large diameter side of the outer ring raceway and the inner ring raceway. When the supply amount of the lubricating oil is sufficient, the lubricating oil flowing through the bearing inner space in this way is connected to the large-diameter side end surface of each tapered roller and the axial inner surface of the large-diameter side flange of the inner ring outer peripheral surface. Also fully lubricate the sliding contact area. Further, in this state, a part of the lubricating oil flowing in the bearing inner space flows into the oil retaining recess formed on the inner peripheral surface of the large-diameter side rim portion while flowing from the opening on each pocket side. It is discharged to the outer edge side in the axial direction of the radial rim portion. In other words, the lubricating oil that has previously entered the oil retaining recess is pushed out of the oil retaining recess by the lubricating oil that newly flows from the opening. Accordingly, during normal operation in which the lubricating oil is sufficiently supplied, the lubricating oil always remains (exists) in the oil retaining recess.

  From this state, if the flow rate of the lubricating oil in the bearing inner space decreases or becomes zero due to, for example, a failure of the lubricating oil supply pump or leakage of the lubricating oil from the casing, the pocket side The feed of the lubricating oil from the opening of the oil into the oil retaining recess is reduced or stopped. In this way, in a state where the feeding of the lubricating oil from the opening is reduced or stopped, the lubricating oil that has already accumulated in the oil retaining recess is transferred from the oil retaining recess to the outer edge side of the large-diameter rim portion. It is not pushed out and stays in this oil retaining recess. Then, the lubricating oil remaining in the oil retaining recess enters the large diameter end surface portion of the tapered roller held in the pocket (preferably in the recess formed on the large diameter end surface), and this Along with the rotation of the tapered roller, it is sent to the sliding contact portion on the large diameter side end surface and the axially inner side surface of the large diameter side flange, and the sliding contact portion is lubricated. The lubricating oil remaining in the oil retaining recess when the failure or leakage occurs can use a large portion of the lubricating oil for lubricating the sliding contact portion. Therefore, it is possible to sufficiently lengthen the time from the occurrence of the poor lubrication state until the rotation becomes impossible due to seizure. For this reason, the vehicle can be operated to a place where it does not get in the way, and the time required for the restoration of the railway can be shortened, and it is difficult to cause traffic congestion. Furthermore, the poor lubrication makes it difficult to cause the rotation support portion to become unrotatable, and it is difficult to induce failure of other portions, and it is difficult to cause problems such as cost and time required for repair.

In the case of the tapered roller bearing of the present invention, the number of the oil retaining recesses is the same as the number of the pockets, and the oil retaining recesses provided independently of each other in the circumferential direction are respectively It opens toward the pocket. Therefore, it is necessary to secure the total amount of lubricating oil accumulated in all the oil retaining recesses (total amount of lubricating oil that can be accumulated in the entire cage), and to increase the time from the occurrence of poor lubrication to the inability to rotate. Is advantageous.
Although deviating from the technical scope of the present invention, if the oil retaining recess is formed in a portion aligned with at least a portion of the pocket, the end face on the large diameter side of the tapered roller held in the pocket (preferably, this Lubricating oil is supplied to the inner surface in the axial direction of the large-diameter side collar through the concave portion formed on the large-diameter end surface, and the sliding contact portion between this axial inner surface and the large-diameter end surface of another tapered roller Lubrication is also possible. Accordingly, the oil retaining recesses can be provided, for example, in one or two pocket portions in the circumferential direction.
Further, when the present invention is carried out, the oil retaining recess has a certain depth on the inner end surface side of the large diameter rim portion facing the large diameter end surface of the tapered roller, and is lubricated. If oil can be temporarily stored, the depth is zero on the outer end surface side of this large-diameter side rim (the depth gradually decreases from the inner end surface side to the outer end surface side. It may be a shape that disappears at the intermediate portion in the axial direction of the inner peripheral surface of the side rim portion.

However, as in the invention described in claim 2, if a weir is provided on the outer end surface side of the large-diameter side rim portion of the oil retaining recess, the volume of the oil retaining recess is increased and The amount of lubricating oil that can be stored in the oil retaining recess is increased, and when the lubrication is poor, the lubricating oil stored in the oil retaining recess is not washed away to the outer end surface side of the large-diameter side rim portion. It can be used more effectively for lubrication of the sliding contact portion between the large-diameter side end surface of the tapered roller and the axially inner side surface of the large-diameter side flange .

Further, like the invention described in claim 3, or the bottom of each Hoyu recess, it is inclined in a direction toward the radially outward in accordance with the over the entire axial length towards the respective pocket, the larger diameter the inner peripheral surface of the rim portion, or parallel to the center axis cylindrical surface of the retainer if the inclined surface inclined in a direction toward the radially outward toward the respective pocket, each Hoyu the recess In addition, the lubricating oil accumulated on the inner diameter and the lubricating oil adhering to the inner peripheral surface of the large-diameter side rim can be efficiently guided toward the large-diameter side end surface of each tapered roller. In particular, if an inclined surface is used, the lubricating oil that flows to the outer end surface side of the large-diameter side rim portion can be suppressed to zero or slightly, and the lubricating oil adhering to the inner peripheral surface can be used more efficiently. As a result, when a poor lubrication occurs, the lubricating oil remaining on the large-diameter end of the cage is removed from the large-diameter end surface of each tapered roller and the axial inner surface of the large-diameter flange. Can be effectively used for lubrication of the sliding contact portion, and the time from the occurrence of the poor lubrication state to the impossibility of rotation can be made longer.

Further, if the cage is made of a synthetic resin like the tapered roller bearing of the present invention, the cage can be reduced in weight and cost. That is, the cage can be made of a metal such as an iron-based alloy or a copper-based alloy , although this is outside the technical scope of the present invention . When building a metal cage, first, an annular material is cut or a plate material is bent by a press to obtain an intermediate material that does not have the oil retaining recesses. . Thereafter, the oil retaining recesses are cut to form the oil retaining recesses. The metal cage manufactured in this way can obtain great strength and rigidity, which is advantageous from the viewpoint of ensuring durability in a normal use state, but increases in weight and manufacturing cost. On the other hand, if the cage is made of synthetic resin, the weight can be reduced due to the small specific gravity of the material. If this cage is made by injection molding as described below, the oil retaining recesses can be molded simultaneously with other portions of the cage, and the manufacturing cost can be reduced.

When making a cage made of synthetic resin, it is possible to use injection molding, in which a thermoplastic synthetic resin is heated and melted, and is fed into the molding space (cavity) of the mold apparatus under pressure. In general, the manufacturing cost is reduced. In the case of synthetic resin injection molding, the synthetic resin fed into the molding space from a feeding port called a gate enters a predetermined part of the molding space from the opposite side and abuts at the predetermined part, and the part A portion called “weld” having a low strength against stress is generated. On the other hand, when the cage is used, each tapered roller held in each pocket presses each column portion that divides both sides in the circumferential direction of each pocket based on the difference in revolution speed of each pocket in the circumferential direction. There are things to do. As a result of this pressing, a stress in the bending direction is applied to the continuous portion between both end portions of each column portion and both the large-diameter side and small-diameter side rim portions. If such welds as described above are present in each of these continuous portions, damage such as cracks may occur in each of these continuous portions with use over a long period of time. On the other hand, according to the invention described in claim 4 , since there is no weld in each of the continuous portions, it is easy to ensure the durability of the cage. In other words, even if the cross-sectional area of the cage is not increased (the size of the cage is not increased), the required durability can be easily ensured.

Although the use part of the tapered roller bearing of this invention is not specifically limited, Like the invention described in Claim 5, it is preferable to use it for the rotation support part of the drive system of a self-propelled vehicle. In the case of a drive system for a self-propelled vehicle, it is difficult to supply lubricating oil from the outside. Grease enclosed in a tapered roller bearing, or lubricating oil (differential oil or mission oil) stored in a housing containing the rotation support portion. ) Is generally lubricated. In addition, the service period is often long, and the actual condition is that the lubrication state is not frequently monitored. For these reasons, there is a greater possibility that a lubrication failure may occur suddenly compared to, for example, a rotating support portion of a machine tool or an industrial machine. When damage such as seizure occurs due to poor lubrication, the influence (nuisance) on the surroundings is larger than that of the machine tool or industrial machine as described above. Therefore, if the tapered roller bearing of the present invention is used for the rotation support portion of the drive system of the self-propelled vehicle as described above, the effects of the present invention as described above can be remarkably obtained.

As in the invention described in claim 4 above, a cage made of synthetic resin in which the weld is present in a portion that is separated from a continuous portion between the two rim portions and the pillar portions is described in claim 6 . It can be easily obtained by carrying out the described invention. That is, among the rim part molding spaces, the synthetic resin in the molten state fed into the molding space of the mold apparatus from the feeding port provided in the portion where the phases in the circumferential direction coincide with each other, After flowing through the rim portion forming spaces in the circumferential direction, the respective column portion forming spaces are entered into the respective column portion forming spaces to form the respective column portions, and the respective column portion forming spaces are formed. At the middle of the working space, a weld is formed at that portion. Therefore, no weld is formed at the continuous portion between the end portion of each column portion and the rim portions. For this reason, the retainer which is easy to ensure durability as described in the said Claim 4 can be obtained at low cost.

Further, as in the invention described in claim 7 , it comprises one mold provided with an oil retaining concave forming convex part in a part of the molding concave part and the other mold provided with the molding convex part. If a mold apparatus having an axial draw structure is used, a synthetic resin cage having the oil retaining recesses can be efficiently produced with a relatively simple mold apparatus.
Further, as in the invention described in claim 8 , if one of the molds has a stepped portion at the tip of the oil retaining recess forming convex portion, it is described in claim 2. As in the above invention, it is possible to efficiently produce a cage made of a synthetic resin that can effectively use the lubricating oil. In addition, it is possible to ensure the sectional area of the tip portion of the oil retaining recess forming convex portion (so that the tip portion does not become thin) and to prevent the tip portion from being damaged, and to ensure the durability of the mold apparatus. .

The fragmentary sectional view of the tapered roller bearing which shows the 1st example of the reference example relevant to this invention . FIG. The perspective view shown in the state which took out the holder | retainer incorporated in the 1st example of the reference example, and was seen from the large diameter side and radial direction outer side. The B section enlarged view of FIG. The fragmentary sectional view of the tapered roller bearing which shows the 1st example of embodiment of this invention. The fragmentary sectional view of the tapered roller bearing which shows the 2nd example of the reference example relevant to this invention . FIG. 7 is an enlarged view of a portion C in FIG. 6. The perspective view shown in the state which took out the holder | retainer built in the 2nd example of the reference example, and was seen from the large diameter side and radial direction outer side. The D section enlarged view of FIG. The fragmentary sectional view of the tapered roller bearing which shows the 2nd example of embodiment of this invention. The fragmentary sectional view of the tapered roller bearing which shows the 3rd example . FIG. The perspective view shown in the state which took out the holder | retainer incorporated in the 3rd example of embodiment and was seen from the small diameter side and radial direction outer side. FIG. 14 is an enlarged view of a portion in FIG. 13. The partial cutting perspective view which shows a pair of metal mold | die which comprises the metal mold | die apparatus used when the holder which comprises each reference example and each embodiment is manufactured by the injection molding of a synthetic resin in the state mutually spaced apart. The partial cut perspective view which shows the 1st example of the general tapered roller bearing known conventionally. The fragmentary sectional view which shows the 2nd example. The perspective view similar to FIG. 3 which takes out and shows the holder | retainer integrated in this 2nd example. The G part enlarged view of FIG. The fragmentary sectional view which shows the 1st example of the conventional structure in which the countermeasure for the seizure prevention was completed. The fragmentary sectional view which shows the 2nd example. The perspective view shown in the state which took out some cages built in this 2nd example and was seen from the large diameter side and radial direction outer side. FIG. 4 is a partial cross-sectional view of a tapered roller bearing with a large contact angle that is likely to have a problem when lubrication is poor. The perspective view similarly shown in the state which took out the retainer and was seen from the large diameter side and radial direction outer side. FIG. 25 is an enlarged view of a part in FIG. 24. The partial cutaway perspective view which shows a pair of metal mold | die which comprises the metal mold | die apparatus used when the holder | retainer which comprises a conventional structure is manufactured by the injection molding of a synthetic resin in the state mutually separated.

[ First example of reference example related to the present invention ]
1 to 4 show a first example of a reference example related to the present invention . The features of the present invention, including the structure of this reference example , are characterized by the occurrence of poor lubrication by devising the shape and structure of the large-diameter end of the cage and the large-diameter end of each tapered roller. The purpose is to extend the time from the time until it becomes unrotatable. The other basic configuration of the tapered roller bearing is the same as that of the conventionally known tapered roller bearing shown in FIGS. 16, 20, and 21 described above. Thus, overlapping description will be omitted or simplified, and the following will focus on the features of this reference example and the portions that have not been described previously.

The cage 5d constituting the tapered roller bearing 1 of this reference example is a so-called saddle type cage which is integrally formed by injection molding synthetic resin or by machining a metal material. The whole is formed in a partial conical cylinder shape. The type of synthetic resin for injection molding is not particularly limited. For example, polyamide 66 (PA66), polyamide 46 (PA46), polyphenylene sulfide (PPS), and the like are generally used for injection molding of cages made of synthetic resin. Various synthetic resins that have been used can be used. Any synthetic resin can be used alone or mixed with a reinforcing fiber such as carbon fiber or glass fiber or a ceramic whisker for reinforcement. Moreover, as a metal material, iron-type alloys, such as steel materials and stainless steel materials, copper-type alloys, such as brass, etc. can be used.

  In any case, in the large-diameter side rim portion 12a, the portion between the column portions 14a, 14a adjacent to each other in the circumferential direction, in other words, the phase in the circumferential direction coincides with each pocket 15a, 15a (each of these Oil retaining recesses 19 and 19 are provided on the inner peripheral surfaces of the portions (aligned with the large-diameter side ends of the pockets 15a and 15a), respectively. Each of these oil retaining recesses 19 and 19 has a claw shape when viewed in the radial direction (from the inner diameter side) of the cage 5d, and the width in the circumferential direction is wider toward the pockets 15a and 15a. These pockets become narrower as they move away from the pockets 15a and 15a. Further, the depth of the oil retaining recesses 19 and 19 with respect to the radial direction (thickness direction) of the cage 5d is deeper toward the pockets 15a and 15a, and gradually decreases with increasing distance from the pockets 15a and 15a. To do.

The depths of the oil retaining recesses 19, 19 are zero at the outer edge portion of the large diameter rim portion 12a. Therefore, these oil retaining recesses 19 and 19 are opened only on the inner diameter side of the cage 5d and the pockets 15a and 15a, and are not opened on both sides in the circumferential direction and on the outer side in the axial direction. Of the oil retaining recesses 19 and 19, the bottom portion which is the deepest portion in the width direction in the circumferential direction in the circumferential direction is radially outward toward the pockets 15a and 15a. Is inclined by an angle θ _{1 with} respect to the central axis of the cage 5d. In short, the oil retaining recesses 19, 19 are made deeper toward the center in the width direction and further toward the pockets 15a, 15a at the center in the width direction (in the axial direction). , 15a is inclined in a direction toward the radially outward direction of the cage 5d. Accordingly, the cross-sectional shape of each of the oil retaining recesses 19, 19 with respect to a virtual plane orthogonal to the axial direction of the cage 5 d is an arc shape that is deepest in the width direction at the center in the width direction with respect to the circumferential direction. It is.

  Further, a recess 20 is formed at the center of the large-diameter end face 10 of each tapered roller 4a that is rotatably held in each of the pockets 15a, 15a. In the case of the illustrated example, the concave portion 20 is circular, but it may also be an annular shape (the central portion of the large-diameter side end face 10 is left without being recessed). In any case, the center of the recess 20 is positioned on the central axis of each tapered roller 4a. And the part opened to the inner surface of each said pocket 15a, 15a among the bottom surfaces of each said oil retaining recessed part 19 and 19 is the large diameter side end surface of the said tapered roller 4a hold | maintained in the said pocket 15a, 15a. 10 is made to face the recess 20 formed in 10. In addition, regarding the radial direction of each of these tapered rollers 4a, a portion (point X portion in FIG. 2) of the bottom of each of the oil retaining recesses 19 and 19 that opens to the inner surface of each of the pockets 15a and 15a It is located inside the outer peripheral edge of the recess 20. Accordingly, the inner surface side openings of the pockets 15 a and 15 a of the oil retaining recesses 19 and 19 are entirely opposed to the recess 20. For this reason, the lubricating oil which exists in each said oil retaining recessed part 19 and 19 and was pressed on the bottom part of each these oil retaining recessed parts 19 and 19 by the centrifugal force based on rotation of the said holder | retainer 5d has almost the whole quantity. , The pockets 15a and 15a tend to flow into the recess 20 through the openings on the inner surface side. The opening edge of each of the oil retaining recesses 19, 19 on the side of the pockets 15 a, 15 a is substantially flat on the flat portion of the large-diameter side end surface 10 that is located around the recess 20. Thus, they face each other through sliding contact or a minute gap. Accordingly, the lubricating oil that has flowed into the recess 20 flows outward in the radial direction of the tapered roller bearing 1 regardless of the centrifugal force based on the revolving motion of each tapered roller 4a or the rotational motion of the cage 5d. Hard to do.

During operation of the rotary machine device incorporating the tapered roller bearing of the present reference example configured as described above, the lubricating oil is pumped on the inner peripheral surface of the outer ring 2 by the pumping action based on the centrifugal force associated with the revolving motion of each tapered roller 4a. 1 flows from the small diameter side to the large diameter side of the outer ring raceway 6 and the inner ring raceway 7 (from the upper left to the lower right in FIG. 1). When the supply amount of the lubricating oil is sufficient, the lubricating oil flowing in the bearing inner space 21 in this way is the large diameter side end surface 10 of each tapered roller 4 a and the large diameter side of the outer peripheral surface of the inner ring 3. The sliding contact portion with the axially inner side surface 11 of the large-diameter side flange portion 8 provided at the end portion is sufficiently lubricated. In this state, a part of the lubricating oil flowing in the bearing inner space 21 is in the oil retaining recesses 19 and 19 formed at a plurality of locations on the inner peripheral surface of the large-diameter side rim portion 12a. While flowing in from the opening on the side of each pocket 15a, 15a, it is discharged to the outer edge side in the axial direction of the large-diameter side rim portion 12a. That is, the lubricating oil that has entered the oil retaining recesses 19 and 19 previously flows from the respective oil retaining recesses 19 and 19 by the lubricating oil newly flowing from the openings on the pockets 15a and 15a side. Extruded. Therefore, during normal operation in which the lubricating oil is sufficiently supplied, the lubricating oil is always accumulated (exists) in each of the oil retaining recesses 19 and 19.

  From this state, when the flow rate of the lubricating oil in the bearing internal space 21 decreases or becomes zero due to, for example, a failure of the lubricating oil supply pump or leakage of the lubricating oil from the casing, The feeding of the lubricating oil into the oil retaining recesses 19 and 19 from the openings on the pockets 15a and 15a side is reduced or stopped. In this way, when the feeding from the opening is reduced or stopped, the lubricating oil that has already accumulated in the oil retaining recesses 19, 19 is transferred from the oil retaining recesses 19, 19 to the large-diameter rim. It is not pushed out to the outer edge side of the part 12a, and remains in each of these oil retaining recesses 19 and 19. In this state, the lubricating oil in each of the oil retaining recesses 19 and 19 tends to be pressed against the bottom surface of each of the oil retaining recesses 19 and 19 due to the centrifugal force accompanying the rotation of the cage 5d. Since the bottom surfaces of the oil retaining recesses 19 and 19 are inclined with respect to the width direction and the axial direction as described above, most of the lubricating oil remaining in the oil retaining recesses 19 and 19 Of the recesses 20 formed in the large-diameter end surface 10 of the tapered rollers 4a held in the pockets 15a and 15a, the tapered roller bearing 1 enters an outer portion in the radial direction. Then, the lubricating oil that has entered the recess 20 is brought into contact with the sliding contact portion between the large-diameter side end surface 10 and the large-diameter side flange portion 8 in the axial direction along with the rotation of the tapered rollers 4a. It is sent (soaks into this sliding contact portion) and lubricates this sliding contact portion.

  As is clear from the above description, the lubricating oil remaining in each of the oil retaining recesses 19 and 19 at the time of occurrence of the failure or leakage is used for lubrication of the sliding contact portion. it can. Therefore, it is possible to sufficiently lengthen the time from the occurrence of the poor lubrication state until the rotation becomes impossible due to seizure. According to the seizure experiment by the oil dipping performed by the present inventor, the tapered roller bearing having the structure shown in FIGS. 1 to 4 is less depleted in lubricating oil than the conventional structure shown in FIGS. The time required for image sticking to be increased by about three times. For this reason, if measures such as detecting the occurrence of poor lubrication with sensors are taken, measures such as slowing down the operating speed or stopping in a safe state can be taken with sufficient margin before seizure occurs. It becomes possible. And before the burn-in occurs, the vehicle can be operated to a place where it does not get in the way, so that the time required for the restoration of the railway can be shortened and it is difficult to cause traffic congestion. Furthermore, the poor lubrication makes it difficult to cause the rotation support portion to become unrotatable, and it is difficult to induce failure of other portions, and it is difficult to cause problems such as cost and time required for repair.

[ First example of embodiment]
FIG. 5 shows a first example of an embodiment of the present invention corresponding to claims 1, 3 and 4 . In the case of this example, not only the bottom portion of the oil retaining recess 19 formed in the inner peripheral surface of the large-diameter side rim portion 12b and the portion that aligns with each pocket 15a, but also the circumferential disengagement from each of these oil retaining recesses 19. and the large diameter side rim portion 12b original inner circumferential surface also, in a direction toward the radially outward toward the respective pockets 15a, the center axis of the cage 5e, is inclined by an angle theta ₂ minutes. According to such a structure of the present example, not only the oil retaining recess 19 but also the lubricating oil adhering to the inner peripheral surface of the large-diameter side rim portion 12b, each retained in each pocket 15a. It can guide efficiently toward the large diameter side end face 10 of the tapered roller 4a. As a result, when a poor lubrication state occurs, the lubricating oil remaining at the large-diameter end of the cage 5e is transferred to the large-diameter end surface 10 of each tapered roller 4a and the large outer peripheral surface of the inner ring 3. It can be effectively used for lubrication of the sliding contact portion of the large-diameter side flange portion 8 provided at the radial side end portion with the axially inner side surface 11, and the time from the occurrence of the poor lubrication state to the impossibility of rotation becomes longer. it can.
Since the configuration and operation of other parts are the same as those of the first example of the reference example described above, overlapping illustrations and descriptions are omitted.

[ Second example of reference example related to the present invention ]
6 to 9 show a second example of a reference example related to the present invention . This reference example shows a case where the structure of the tapered roller bearing 1 in which the contact angle of each tapered roller 4a is larger than that of the first example of the reference example described above and the first example of the embodiment is adopted . As described above, the outer ring raceway 6 formed on the inner peripheral surface of the outer ring 2 and the inner ring raceway 7 formed on the outer peripheral surface of the inner ring 3 have a large inclination angle with respect to the central axis, and the rotation axis of each tapered roller 4a and the outer ring In the case of the tapered roller bearing 1 having an inclination angle with respect to the center axis of 2 and the inner ring 3 of 20 degrees or more, further 25 degrees or more, the problem tends to become remarkable even when lubrication is poor. In other words, the time from the occurrence of poor lubrication to the occurrence of serious damage such as seizure tends to be shortened.

On the other hand, a tapered roller bearing with a large contact angle can increase the thrust load capacity, and therefore may be used for a rotation support portion to which a large thrust load is applied. Therefore in the case of the present embodiment is the contact angle is related to the bearing 1 large tapered roller, even when the lubrication of the rotating support a large thrust load is applied becomes defective, before leading to serious damage such as seizure The time required can be lengthened. As described above, the cage 5g incorporated in the tapered roller bearing 1 having a large contact angle has a large difference between the diameter of the large-diameter side rim portion 12c and the diameter of the small-diameter side rim portion 13b. The column part 14b spanned between the two is used with a large inclination angle.
Since the configuration and operation of the other parts are the same as those in the first example of the reference example shown in FIGS. 1 to 4 described above, the same parts are denoted by the same reference numerals, and redundant description is omitted.

[ Second Example of Embodiment]
FIG. 10 shows a second example of an embodiment of the present invention corresponding to claims 1, 3 and 4 . Also in the case of this example, as in the case of the second example of the reference example described above, the tapered roller bearing 1 in which the contact angle of each tapered roller 4a is large is adopted , and the present invention is applied to such a tapered roller bearing 1. The case is shown. Along with this large contact angle, the difference between the diameter of the large diameter rim portion 12c and the diameter of the small diameter rim portion 13b constituting the cage 5h is increased, and the inclination angle of each column portion 14b is increased. Is the same as the second example of the reference example described above, and the inner peripheral surface of the inner peripheral surface of the large-diameter side rim portion 12c that is separated from each oil retaining recess 19 in the circumferential direction is formed in each pocket 15a. Since the point inclined in the radially outward direction as it goes is the same as in the case of the first example of the embodiment shown in FIG. 5 described above, overlapping illustration and description are omitted.

[ Third example of embodiment]
FIGS. 11 to 14 show a third example of the embodiment of the invention corresponding to claims 1 to 5 . In the case of this example, the oil retaining recesses 19a and 19a formed on the inner peripheral surface of the large-diameter side rim portion 12c constituting the cage 5i at the portions where the phases in the circumferential direction are aligned with the pockets 15a and 15a, respectively. The depth dimension of the oil retaining recesses 19a, 19a is also sufficiently large at the back end. In other words, on the outer end surface side (the right end side in FIGS. 11 to 12 and the lower end side in FIGS. 13 to 14) of the large-diameter side rim portion 12c, the insides of the oil retaining recesses 19a and 19a and the large-diameter side rim portion are provided. Weirs 25, 25 are provided to block the outer end surface of 12c so that the oil retaining recesses 19a, 19a and the outer end surface of the large-diameter side rim portion 12c do not penetrate in the axial direction. That is, the large-diameter side rim portion 12c extends from the opening-side end portion on the pocket 15a, 15a side to the back end portion on the outer end surface side of the large-diameter side rim portion 12c. The inner peripheral surface of each of the oil retaining recesses 19a, 19a and the inner peripheral surface of the large-diameter rim portion 12c. Steps 26 and 26 are provided between them. In the case of this example, the portion of the inner peripheral surface of the large-diameter side rim portion 12c that is out of the oil retaining recesses 19a, 19a is simply a cylindrical surface shape whose inner diameter does not change in the axial direction. Yes.

According to the structure of this example in which each of the oil retaining recesses 19a, 19a is provided for each of the pockets 15a, 15a, each having the shape as described above, the volume of each of the oil retaining recesses 19a, 19a is increased. Thus, the amount of lubricating oil that can be stored in each of these oil retaining recesses 19a, 19a can be increased. Further, the lubricating oil stored in each of the oil retaining recesses 19a, 19a at the time of poor lubrication does not flow out to the outer end surface side of the large diameter rim portion 12c, and the large diameter side end surface of each tapered roller 4a. 10 and lubrication of the sliding contact portion between the inner diameter side surface 11 of the large-diameter side flange 8 provided on the outer peripheral surface of the inner ring 3 can be more effectively used. As a result, the time from the occurrence of poor lubrication to the occurrence of a serious failure such as seizure can be further increased.
Since the configuration and operation of the other parts are the same as those in each of the reference examples and the embodiments described above, the same parts are denoted by the same reference numerals, and redundant description is omitted.

[ Fourth Example of Embodiment]
FIG. 15 shows a fourth example of the embodiment of the invention corresponding to claims 6-8 . This example is a conical structure in which a cage incorporated in the structure of each reference example and each embodiment described above (for example, a cage 5i incorporated in the fourth example of the above-described embodiment) is formed by injection molding of a synthetic resin. The present invention relates to a method for manufacturing a roller bearing cage. The basic configuration of the mold apparatus 24a used for carrying out this manufacturing method is the same as that of the mold apparatus 24 shown in FIG. That is, the mold apparatus 24a of the present example includes a pair of molds 22a and 23a that move far and away from each other in the axial direction while being concentrically arranged. Both the molds 22a and 23a define a molding space (cavity) inside the abutting portion in a state where the axial end surfaces facing each other are abutted against each other. Then, the thermoplastic synthetic resin heated and melted through a feeding port (gate) provided in one or both of the molds 22a and 23a is fed into the molding space in a state where pressure is applied, and the cage 5i. Is injection molded by an axial draw.

  A molding recess 27 is formed at the center of the axial end surface (lower surface in FIG. 15) of one of the molds 22a and 23a (upper side in FIG. 15) and the other (lower side in FIG. 15). A molding projection 28 is formed at the center of the axial end face (upper surface in FIG. 15) of the mold. The portions near the outer diameter of the axial end surfaces of the respective molds 22a, 23a, respectively, the portions surrounding the molding concave portion 27 or the molding convex portion 28 are in close proximity to each other (melted in the molding space). Flat surfaces 29a and 29b that can come into contact with each other (so that the synthetic resin does not leak out). The molding space is defined in a portion surrounded by the molding concave portion 27 and the molding convex portion 28 in a state where the flat surfaces 29a and 29b are in contact with each other. Yes.

  In particular, in the case of this example, the cage 5i to be injection-molded at a portion slightly closer to the inside in the radial direction than the peripheral edge of the opening of the molding recess 27 provided on the axial end surface of the one mold 22a. The oil retaining recess forming convex portions 30 and 30 are respectively provided in portions that match the pockets 15a and 15a (phases in the circumferential direction coincide with each other). These oil retaining recess forming convex portions 30 and 30 are provided with oil retaining recesses 19a, in portions aligned with the pockets 15a and 15a in the inner peripheral surface of the large diameter rim portion 12c constituting the retainer 5i. 19a is formed in a portion near the inner diameter of the large-diameter side rim portion forming space for forming the large-diameter side rim portion 12c. The front end surfaces (lower end surfaces) of the respective oil retaining recess forming convex portions 30 and 30 are flat surfaces, and are positioned in portions slightly recessed with respect to the axial direction (vertical direction) relative to the flat surface 29a. And the weirs 25 and 25 demonstrated in above-mentioned FIGS. 11-14 can be formed in the back end part of each said oil retaining recessed part 19a and 19a. Further, the cross-sectional area of the tip portions of the oil retaining recess forming convex portions 30 and 30 is ensured, in other words, the tip portions of the oil retaining recess forming convex portions 30 and 30 are thinly pointed. To prevent it. And the front-end | tip part of each oil-retaining recessed part shaping | molding convex part 30 and 30 is made hard to be damaged so that the durability of the said mold apparatus 24a can be ensured. In addition, a pair of molds is formed so that there is no so-called undercut portion in which the base end side portion is recessed in the radial direction in any part of both the molds 22a and 23a compared to the tip end side portion. An axial draw in which the cage 5i is injection-molded only by the molds 22a and 23a is possible.

  The molding is defined between the two molds 22a and 22b in a state where the flat surfaces 29a and 29b of the molds 22a and 22b are in contact with each other, each having the structure as described above. For example, molten synthetic resin can be fed into the working space through a feed port (not shown) provided in, for example, the one mold 22a (or the other mold 23a). Such an infeed port forms a large-diameter side rim portion molding space portion for molding the large-diameter side rim portion 12c of the retainer 5i and at least the small-diameter side rim portion 13b in the molding space. And a small-diameter-side rim portion forming space portion to be provided. Further, the installation positions of the respective inlets are made to coincide with each other between the two rim portion forming space portions with respect to the circumferential direction of the both rim portion forming space portions. Preferably, each of the infeed ports should be formed in a part of the large-diameter side rim portion molding space portion and a part of the small-diameter side rim portion molding space portion and the column portions 14b and 14b adjacent in the circumferential direction. Provided at each middle part.

  In order to injection-mold the retainer 5i by the mold device 24a having the above-described configuration, the mold device 24a can be formed from the feed ports provided in the large-diameter side and small-diameter side rim portion molding spaces. A molten synthetic resin is fed into the molding space. Then, this synthetic resin flows in the circumferential direction in both the rim part forming spaces, and then into each column part forming space for forming each column part, from both ends of each column part forming space. enter in. And it hits in the middle part of each of these column part forming space, and a weld is formed in the part concerned. Welds are not formed at the continuous portions between the end portions of the column portions 14b and 14b and the rim portions 12c and 13b on both the large diameter side and the small diameter side. For this reason, regardless of the use over a long period of time, damage such as cracks is unlikely to occur in each of the continuous portions, and the durability of the cage 5i is easily ensured. In addition, the synthetic resin in the molten state that has flowed from the inlets adjacent to each other in the circumferential direction toward the respective column part forming spaces merges at the inlet portion of each of these column part forming spaces, and then each of these column parts. Enter the molding space. At this entrance portion, the temperature of the synthetic resin is still sufficiently high, so that no weld is formed in the portion.

1 Tapered roller bearing 2 Outer ring 3 Inner ring 4, 4a Tapered roller 5, 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i Cage 6, 6a Outer ring raceway 7, 7a Inner ring raceway 8 Large diameter side flange 9 Small-diameter side flange portion 10 Large-diameter side end surface 11 Axial inner side surface 12, 12a, 12b, 12c Large-diameter side rim portion 13, 13a, 13b Small-diameter side rim portion 14, 14a, 14b Column portion 15, 15a Pocket 16 Bending plate Part 17, 17a Oil retaining part 18 Partition plate part 19, 19a Oil retaining recess 20 Recess 21 Bearing inner space 22, 22a Mold 23, 23a Mold 24, 24a Mold device 25 Weir 26 Step 27 Molding recess 28 Molding Convex part 29a, 29b Flat surface 30 Convex part for oil retaining recess molding

JP 2007-40512 A JP 2007-270851 A

Claims (8)

An outer ring having a conical concave outer ring raceway on the inner peripheral surface, a conical convex inner ring raceway on the outer peripheral surface and concentric with the outer ring on the inner diameter side of the outer ring, and a large diameter side end of the inner ring raceway An inner ring having a large-diameter side flange projecting outward in the radial direction from the portion, and is arranged to freely roll between the inner ring raceway and the outer ring raceway, and the respective large-diameter side end faces of the large-diameter side collar A plurality of tapered rollers opposed to the axial side surface of the portion, and a synthetic resin cage for holding each tapered roller, the cages being concentric with each other and spaced in the axial direction A large-diameter side rim part and a small-diameter side rim part, each of which is annular, and a plurality of column parts spanned between the two rim parts, both rim parts And the part surrounded by the circumference by a pair of pillars adjacent in the circumferential direction Each at the each tapered roller tapered roller bearings and has a pocket and structure for holding the said among the large diameter side rim portion, a portion where the phase in the circumferential direction is matched to the each pocket The inner peripheral surface portion is provided with the same number of oil retaining recesses as the respective pockets in a state of being recessed from each other in the circumferential direction and radially outward, and the shafts of the cages of the respective oil retaining recesses. The cross-sectional shape related to the virtual plane orthogonal to the direction is an arc shape that is deepest at the center in the width direction with respect to the circumferential direction, and is open to the inner surface of each pocket among the bottom surfaces of the oil retaining recesses. The part is opposed to the end face on the large diameter side of the tapered roller held in each pocket ,
Of the inner peripheral surface of the large-diameter side rim portion, a portion that is circumferentially removed from each oil retaining recess extends over the entire length in the axial direction, and is a cylindrical surface parallel to the central axis of the cage or the A tapered roller bearing characterized by an inclined surface that is inclined in a direction toward a radially outward direction toward each pocket . In each of the oil retaining recesses, from the opening side end of each pocket side to the back end of the outer diameter side of the large diameter rim portion, radially outward from the inner peripheral surface of the large diameter rim portion. by giving the direction of the depth of recessed, the outside end face of the large diameter side rim portion of the Hoyu recess, blocking the outer end face of the inner and the large diameter side rim portion of the Hoyu recess The tapered roller bearing according to claim 1, wherein a weir is provided. The cone according to any one of claims 1 to 2 , wherein a bottom portion of each oil retaining recess is inclined in a radially outward direction toward the respective pockets over the entire axial length. Roller bearing. The cage is made by feeding a synthetic resin having thermoplasticity in a molten state into a molding space of a mold apparatus through a plurality of inlets in a state where pressure is applied. , There is a weld that occurs when a synthetic resin in a molten state fed from different feed ports strikes, and this weld exists in a portion that is out of the continuous portion between the two rim portions and the column portions, The tapered roller bearing described in any one of Claims 1-3 . Is provided between the drive source of the vehicle and the driving wheels, is used to support part of the rotary shaft constituting the vehicle driving system for transmitting the rotational driving force of the driving source to the driving wheel, according to claim 1 The tapered roller bearing described in any one of? It is a manufacturing method of the holder | retainer integrated in the tapered roller bearing described in Claim 4 , Comprising: As the said mold apparatus, the feeding port for sending the synthetic resin of a molten state in the said molding space is this molding space. Among the rim portions forming space portions for forming the rim portions, and the positions of the feeding ports are set in relation to the circumferential direction of the rim portion forming space portions. A method for manufacturing a tapered roller bearing retainer, wherein the molding space portions are matched with each other. A method for manufacturing a tapered roller bearing retainer incorporated in a tapered roller bearing according to any one of claims 1 to 5 , wherein the mold device includes the following (1) to (3): A method for producing a tapered roller bearing retainer characterized by using a material that satisfies all the conditions.
(1) An axial draw structure in which a pair of molds arranged concentrically with each other is moved in the axial direction.
(2) A molding concave portion is provided on the axial end surface of one of the axial end surfaces facing each other of the molds, and a molding convex portion is provided on the axial end surface of the other die. Yes.
(3) An oil retaining recess forming convex portion for forming the oil retaining recess is provided on the axial end surface of the one mold. The method for manufacturing a tapered roller bearing retainer according to claim 7 , wherein a mold having a stepped portion at a tip of the oil retaining recess forming convex portion is used as the one mold.

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