JP2008045602A - Pin type cage and roller bearing equipped therewith - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pin type cage having improved durability, and to provide a roller bearing equipped therewith. <P>SOLUTION: A pin 13 is subjected to heat treatment or formed of a highly hard material (including heat treatment). A second ring 12 welded and fixed to the pin 13 is not subjected to heat treatment. On a female screw 15 of a first ring 11, a hardened face 15a is formed by induction hardening to reduce a property difference, particularly a hardness difference between the pin 13 subjected to heat treatment and/or formed of the highly hard material and itself. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a pin type cage for holding hollow rollers and a roller bearing provided with the pin type cage.

  In steelmaking facilities where large loads and impact loads are applied, hollow rollers are used as rollers for roller bearings in order to increase the capacity. In such roller bearings, they are arranged at predetermined intervals in the axial direction. There is used a pin-type cage composed of first and second rings and a plurality of pins spanned between both rings. To fix each pin and ring, on the first ring side, the male screw formed on the pin end is fixed to the female screw, and on the second ring side, the pin end is provided on the ring. It is set as welding fixation inserted in the fitting hole and welded.

In such a pin type cage, durability is important, and as a failure mode, the pin is often damaged on the welding fixing side. Therefore, Patent Document 1 discloses the second ring to be welded. It has been proposed to quench the fitting hole.
JP 2004-278694 A

  In the thing of the said patent document 1, although the quenching is performed to the ring of the welding fixed side, although the strength improvement of a failure generation part is possible by quenching, quenching is disadvantageous with respect to the crack at the time of welding. There is a problem that a sufficient durability improvement effect cannot be obtained.

  That is, such a pin type cage is subjected to a load or vibration from a roller on the pin where it is used in a place where sudden acceleration / deceleration is applied, such as for a reduction gear, or when external vibration is applied. Over a long period of time, looseness occurs in the screw fixing portion. The backlash of the screw fixing portion causes damage to the pin on the weld fixing portion side, and it is necessary to prevent this backlash.

  An object of the present invention is to provide a pin type cage having improved durability and a roller bearing provided with the pin type cage.

  A pin-type cage according to the present invention includes first and second rings arranged at predetermined intervals in the axial direction, and a plurality of pins spanned between the two rings. The pin-type holding is a screw fixing in which the male screw formed on the screw is screwed to the female screw, and on the second ring side, the pin end is inserted into a fitting hole provided in the ring and welded. The second ring to be welded and fixed is not heat-treated, and the male screw and the female screw fixed to the screw are heat-treated.

  The male thread is formed integrally with the pin end, and the female thread may be formed on the ring, or may be a nut that is a separate member from the ring.

  The heat treatment may be performed only on the male screw and the female screw by, for example, induction hardening, or the entire pin having the male screw and the entire ring or nut having the female screw may be quenched.

  In the conventional pin type cage, the ring is not heat-treated, and the pin is quenched or a high-hardness material (usually quenched) is used. Therefore, the pin is harder than the ring. Therefore, the present inventor has a large hardness difference between the pin and the ring, so that the female screw of the ring is worn by the pin, thereby causing looseness of the screw fixing portion, and the pin is in a cantilever state. Based on the inference that the pin is broken on the fixed side, the durability is improved by increasing the strength of the screw fixing side, which is the opposite side of the welding fixing side, which is the final failure site.

  The screw fixing is a configuration for connecting the pin and the first ring first, and the screw may be a straight screw or a taper screw. Of course, a female thread portion may be formed in the ring, but a through hole may be formed in the ring, and a nut may be tightened by inserting a male screw therethrough.

  Welding fixing is a configuration for connecting the pin and the second ring later, and of course, fitting the end into the fitting hole and welding the end to the fitting hole via a bush Then, welding may be performed, and further, a screw may be formed at the end of the pin and a nut may be fastened to the pin, and then the nut may be spot welded to prevent rotation.

  In the pin type cage according to the present invention, on the first ring side, the small diameter shaft portion formed at the pin end portion is inserted into the through hole formed in the first ring, and the small diameter shaft portion protruding from the first ring is provided. A screw may be formed in the portion, and a nut as a female screw may be screwed onto this male screw. In this case, it is preferable that the nut and the first ring are quenched.

  If it does in this way, since it can be contact-fixed in the surface (the step surface of a pin, the end surface of a nut, and the surface of the ring which contact | abuts this), coupling strength becomes large. At this time, the contact surface of the first ring needs not to be easily deformed, and it is preferable that the first ring is subjected to a quenching treatment with a degree of tempering. The same applies to the nut, and it is preferable to perform a quenching treatment of a tempering degree. Further, it is more preferable to perform welding so that the nut does not loosen.

  The roller bearing according to the present invention is a roller bearing comprising an outer ring, an inner ring, a plurality of rollers, and a pin type cage having a plurality of pins for holding the rollers, and the pin type cage is any of the above. It is characterized by.

  Examples of such roller bearings include cylindrical roller bearings, tapered roller bearings, and spherical roller bearings.

  According to the pin type cage of the present invention and the roller bearing equipped with the same, heat treatment is applied to the male screw and the female screw, respectively, so that the difference in hardness between the two is reduced. Screw wear is suppressed. Thereby, the backlash of the thread part which causes damage to the pin on the weld fixing part side is prevented, and durability is improved.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 shows a first embodiment of a pin type cage and a roller bearing according to the present invention.

  The pin type cage (10) is used in a cylindrical roller bearing (1) composed of an outer ring (2), an inner ring (3) and a cylindrical roller (4), and is arranged at a predetermined interval in the axial direction. The first and second rings (11) and (12) and a plurality of pins (13) spanned between the rings (11) and (12).

  On the first ring (11) side, the male screw (14) formed at the end of the pin (13) is formed on the first ring (11) and is therefore screwed to be screwed onto the screw (15). .

  On the second ring (12) side, the end (16) of the pin (13) is inserted into the fitting hole (17) formed in the second ring (12) and welded and fixed by the welded portion (18). ing. The end (16) of the pin (13) on the second ring (12) side has a tapered portion, and the pin (13) is screwed to the first ring (11) at the tip. An engaging portion (16a) to which a screwdriver for engaging is engaged is formed.

  Each pin (13) is heat treated or is made of a high hardness material (heat treated), and the female screw (15) of the first ring (11) is a pin (with heat treatment and / or made of a hard material ( In order to reduce the difference in characteristics from 13), in particular the hardness difference, induction hardening is performed to form a quenched surface (15a). Instead of induction hardening, the entire first ring (11) may be hardened to form the hardened surface (15a) of the female screw (15). The second ring (12) is not subjected to heat treatment because it may break during welding fixation.

  FIG. 2 shows a second embodiment of the pin type cage and roller bearing according to the present invention.

  The pin type cage (20) is used in a cylindrical roller bearing (1) composed of an outer ring (2), an inner ring (3) and a cylindrical roller (4), and is arranged at a predetermined interval in the axial direction. The first and second rings (21) and (22) and a plurality of pins (23) spanned between the rings (21) and (22).

  On the first ring (21) side, the small diameter shaft portion (24) formed at the end of the pin (23) is inserted into the through hole (25) formed in the first ring (21), and the first ring ( A screw (26) is formed in the portion of the small-diameter shaft portion (24) protruding from 21), and the nut (32) as a female screw is screwed onto the male screw (26).

  On the second ring (22) side, the end (28) of the pin (23) is inserted into a bush (30) fitted in a fitting hole (29) formed in the second ring (22). It is welded and fixed by the welding part (31). The end (28) of the pin (23) on the second ring (22) side has a tapered portion, and the pin (23) is screwed to the first ring (21) at the tip. An engaging portion (28a) to which a screwdriver for engaging is engaged is formed.

  Each pin (23) is heat treated or made of a hard material (heat treated), and is placed on the first ring (21) side and nut (32) screwed onto the male thread (26) of the pin (23) On the inner periphery, the entire nut (32) is quenched to reduce the characteristic difference, particularly the hardness difference, with heat-treated and / or high-hardness material pins (23). ) Is formed. The second ring (22) is not subjected to heat treatment because it may break during welding fixation.

  There is a step surface (27) between the small diameter shaft portion (24) of the pin (23) and the central portion of the pin (23) connected to this, and the first ring (21) has this step surface ( 27) and the nut (32). Therefore, the pin stepped surface (27), the nut (32), and the portion of the first ring (21) in contact with them become the main portions when receiving a load at the screw fixing portion. Therefore, the first ring (21) is subjected to quenching treatment in order to reduce the characteristic difference, particularly the hardness difference between the pin (23) and the nut (32), which are heat treated and / or made of a high hardness material. Yes. Further, spot welding (33) for preventing rotation of the nut (32) is applied between the first ring (21) and the nut (32).

  FIG. 3 shows a third embodiment of the pin cage and roller bearing according to the present invention.

  The pin type cage (40) is used in a cylindrical roller bearing (1) composed of an outer ring (2), an inner ring (3) and a cylindrical roller (4), and is arranged at a predetermined interval in the axial direction. It consists of a 1st and 2nd ring (41) (42) and several pins (43) spanned between both rings (41) (42).

  On the first ring (41) side, as in the second embodiment, a small diameter shaft portion (44) formed at the end of the pin (43) has a through hole (45) formed in the first ring (41). A screw (46) is formed in the portion of the small diameter shaft portion (44) protruding from the first ring (41), and a nut (51) as a female screw is screwed onto the male screw (46). Screw fixing.

  On the second ring (42) side, the end portion (48) of the pin (43) is formed of a tapered portion (48a) and a small-diameter male screw portion (48b) at the tip thereof, and is formed on the second ring (42). Inserted into the tapered fitting hole (49) and a small-diameter nut (48b) with a small-diameter nut within the large-diameter part (49a) formed at the tip of the tapered fitting hole (49). 52) are screwed together, and the small-diameter nut (52) is welded to the second ring (42) by the welded portion (50). This welded part (50) is used to prevent the small-diameter nut (52) from rotating, and it is not necessary to make the welded part as strong as in the first and second embodiments, and there are several spots in the circumferential direction. What is necessary is just welding. Note that an engagement portion (48c) is formed at the tip of the small diameter male screw portion (48b) to be engaged with a screwdriver for screwing the pin (43) to the first ring (41).

  Each pin (43) has a heat treatment or is made of a high hardness material (heat treatment), and the nut (51) arranged on the first ring (41) side and screwed to the pin (43) has a heat treatment. Hardened surface (51a) is formed by quenching the entire nut (51) in order to reduce the characteristic difference, especially the hardness difference, with the pin (43), which is present and / or a high hardness material. . The second ring (42) is not subjected to heat treatment because it may break during welding fixation.

  There is a step surface (47) between the small diameter shaft portion (44) of the pin (43) and the central portion of the pin (43) connected to the pin (43), and the first ring (41) has this step surface ( 47) and a nut (51). Therefore, the pin step surface (47), the nut (51), and the portion of the first ring (41) in contact with them become the main parts when receiving a load at the screw fixing portion. Therefore, the first ring (41) is subjected to quenching treatment in order to reduce the characteristic difference, particularly the hardness difference between the pin (43) and the nut (51), which are heat treated and / or made of a high hardness material. Yes. Further, spot welding (53) for preventing rotation of the nut (51) is performed between the first ring (41) and the nut (51).

  Although not shown, for example, in the first embodiment, the bush (29) may be used as in the second embodiment, and in the second and third embodiments, the screw fixing side is used. May be the same as in the first embodiment. The configuration on the screw fixing side may be a taper screw instead of the illustrated straight screw, and the configuration on the welding fixing side may be appropriately changed to a configuration other than that illustrated.

FIG. 1 is a longitudinal sectional view showing a pin-type cage according to the present invention and a roller bearing having the pin-type cage according to a first embodiment. FIG. 2 is a longitudinal sectional view showing a pin-type cage according to the present invention and a roller bearing having the same according to a second embodiment. FIG. 3 is a longitudinal sectional view showing a pin-type cage according to the present invention and a roller bearing provided with the same according to a third embodiment.

Explanation of symbols

(1) Cylindrical roller bearing
(2) Outer ring
(3) Inner ring
(4) Cylindrical roller
(10) (20) (40) Pin type cage
(11) (21) (41) First ring
(12) (22) (42) Second ring
(13) (23) (43) Pin
(14) (26) (46) Male thread
(15) Female thread
(15a) Hardened surface
(17) (29) (49) Mating hole
(18) (31) (50) Welding
(24) (44) Small diameter shaft
(25) (45) Through hole
(32) (51) Nut (Female thread)
(32a) (51a) Hardened surface

Claims (4)

The first and second rings are arranged at predetermined intervals in the axial direction, and a plurality of pins are provided between the two rings. On the first ring side, the female thread formed at the end of the pin is a female thread. In the pin type cage that is screwed to be screwed together, and on the second ring side, the pin end is inserted into a fitting hole provided in the ring and welded to be welded.
A pin type cage, wherein the second ring to be fixed by welding is not heat-treated, and the male screw and the female screw to be screw-fixed are respectively heat-treated.   On the first ring side, the small-diameter shaft portion formed at the pin end is inserted into the through-hole formed in the first ring, and a screw is formed at the portion of the small-diameter shaft portion protruding from the first ring. The pin type retainer according to claim 1, wherein a nut as a female screw is screwed onto the male screw.   The pin type retainer according to claim 2, wherein the nut and the first ring are heat-treated.   A roller bearing comprising an outer ring, an inner ring, a plurality of rollers, and a pin type cage having a plurality of pins for holding each roller, wherein the pin type cage is any one of claims 1 to 3. Roller bearing.

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