JP5500769B2 - Deformation correction device for ring-shaped products - Google Patents

Description

  The present invention relates to a ring-shaped product deformation correcting apparatus for correcting deformation of a ring-shaped product such as a bearing race.

  When a ring-shaped product such as a bearing ring or the like is quenched, roundness deviation due to thermal deformation occurs. Therefore, in general, after quenching, the outer periphery of the ring-shaped product is received by a forming roll and the mandrel is pressed against the inner periphery to correct the deformation.

  However, if deformation correction is performed in a separate process from quenching as described above, the number of steps in the production line for the ring-shaped product increases, so that as shown in FIG. It is also practiced to correct the deformation by cooling it in a container. Specifically, after heating the ring-shaped product W to the quenching temperature (about 850 ° C.), the ring-shaped product W is cooled to a temperature in the vicinity of the martensite transformation point (230 ° C.) without being constrained. The product W is put into the constraining die 40, cooled in that state to a certain temperature (about 110 ° C.), and if it is cooled to the same temperature, the ring-shaped product W is taken out from the constraining die 40 and then naturally cooled to room temperature. It is.

In addition, as a kind of deformation correction method using a constraining die, a vertical cylindrical constraining die that is long in the axial direction is used, and this vertical cylindrical constraining die is in the form of a ring in the quenching cooling process in order from the top. There has been proposed a method in which a product is pushed in, and thereby a ring-shaped product in a mold is pushed out in order from the lower side (Patent Document 1).
JP 09-176740 A

  However, the deformation correction method using the constraining die requires that a constraining die that is expensive to manufacture be prepared for each dimension of the ring-shaped product. Moreover, it takes time and effort to fit the ring-shaped product into the constraining die and to take out the ring-shaped product from the constraining die after quenching. In the case of the deformation correction method disclosed in Patent Document 1, it is not necessary to take out the ring-shaped product from the constraining mold, but this method holds the ring-shaped product in the mold by the frictional force between the constraining mold and the ring-shaped product. Therefore, in the case of a ring-shaped product having a large size, there is a possibility that it will fall from the restraint type by its own weight, and it can be applied only to a relatively small ring-shaped product.

  An object of the present invention is to correct deformation without increasing the number of steps of a ring-shaped product production line and cost and labor for thermal deformation generated in the heat treatment process of the ring-shaped product, An object of the present invention is to provide an apparatus for correcting deformation of a ring-shaped product that can be applied to a ring-shaped product of a size.

The deformation correction device for a ring-shaped article according to the present invention is a deformation correction apparatus that corrects deformation while cooling a heated ring-shaped article, and a placement table on which the ring-shaped product in a heated state is placed; through a pair of receiving rolls to each rollably contact with the outer peripheral surface of the ring-shaped article, a receiving roll distance changing mechanism for changing the distance between the pair of receiving rolls, the ring shaped article to the one pair of receiving rolls One pressure roll provided opposite to each other, and the pressure roll advancement / retraction to advance / retreat the pressure roll to a forward position pressed against the outer peripheral surface of the ring-shaped product and a backward position away from the outer peripheral surface a mechanism, characterized in that by the pressure roller advancing and retracting mechanism and a pressure roller rotation drive mechanism including a rotary motor for the pressure roll pressed against the ring-shaped article rotating driven. The ring-shaped product can be, for example, a bearing ring. The bearing ring of the bearing is formed by forging, and a raceway groove is formed on the inner peripheral surface or the outer peripheral surface by turning.

  According to this ring-shaped product deformation correction device, in the cooling process of quenching, a pair of receiving rolls are brought into rolling contact with the outer peripheral surface of the ring-shaped product, and a pressure roll is attached from the opposite side to the ring-shaped product. It is pressed against the outer peripheral surface of and rotated. The ring-shaped product is rotated between both rolls while being sandwiched by a pair of receiving rolls and one pressure roll from both sides with a predetermined load. This corrects the deformation and increases the roundness. Since the pressure roll can move forward and backward, the distance between the receiving roll and the pressure roll can be changed. Therefore, it can be applied to ring-shaped products having various diameters. The deformation correction of the ring-shaped product by this deformation correction apparatus does not use a constraining mold, so that the mold cost is not required, and the labor for fitting the ring-shaped product into the mold and the labor for removing it from the mold are not required. In addition, since the deformation correction apparatus performs deformation correction in the quenching cooling process, the deformation correction apparatus can be installed without increasing the number of steps in the ring-shaped product production line.

Before SL Ru provided receiving roll interval changing mechanism for changing the distance between the pair of receiving rolls. If the interval between the pair of receiving rolls can be changed, a wider range of ring-shaped products can be handled.
The receiving roll interval changing mechanism includes a receiving roll supporting member that supports each receiving roll, a guide that guides the receiving roll supporting member with respect to the arrangement table, and the arrangement of the receiving roll supporting member. The pressure roll rotation drive mechanism includes a rotary motor installed on a pressure roll support member that supports the pressure roll, an output shaft of the rotary motor, and the additional motor. Sprockets attached to the support shafts of the pressure rolls and chains wound around these sprockets may be used.

It is preferable that the time for performing deformation correction by pressing the pressure roll on the outer peripheral surface of the ring-shaped product is 40 seconds to 90 seconds. Here, the time for performing deformation correction is the time from the start of pressing the pressure roll to the end of pressing. The temperature of the ring-shaped article at the time of starting the deformity correction the presses the pressure roller on the outer peripheral surface of the ring-shaped product is to not 20 ° C. than the martensite varying state point temperature to the 50 ° C. higher temperatures good.
As a result of various tests, it was found that the time for performing deformation correction is preferably 40 seconds to 90 seconds. To complete the deformation correction to ensure the deformation correcting time during the cooling process of hardening, to no 20 ° C. than the martensite varying state point temperature may start the deformity correction from 50 ° C. higher temperatures.

It is preferable to provide a cooling oil tank and a deformation correction cooling mechanism that cools the ring-shaped product by immersing it in the quenching oil of the oil tank during the deformation correction. For example, the cooling mechanism during deformation correction includes a support unit that supports the placement table so that the placement unit on which the ring-shaped product is placed on the placement table can be tilted, and the support unit. And a tilting means for tilting the mounting table supported by the ring, and the ring-shaped product can be immersed in the quenching oil of the oil tank by tilting the mounting table by the tilting means.
By providing a cooling mechanism during deformation correction, deformation correction can be performed while cooling the ring-shaped product sufficiently. When the deformation correction cooling mechanism has the support means and the tilting means, the ring-shaped product can be reliably immersed in the oil in the oil tank and cooled while having a simple structure.

A ring-shaped article deformation correction device according to the present invention is a ring-shaped article deformation correction apparatus that corrects deformation while cooling a heated ring-shaped article, and an arrangement table on which a heated ring-shaped article is placed, a pair of receiving rolls to rollably contact respectively with the outer peripheral surface of the placing stand on the ring-shaped article, a receiving roll distance changing mechanism for changing the distance between the pair of receiving rolls, the ring receiving roll of the one pair One pressure roll provided opposite to each other via the shaped article, and this pressure roll is advanced and retracted to a forward position pressed against the outer peripheral surface of the ring-shaped article and a retracted position away from the outer peripheral face. to provide a pressure roll forward and reverse mechanism, and a pressure roll rotation driving mechanism including a rotating motor for the pressure roll pressed against the ring-shaped article rotating driven by the pressure roll forward and reverse mechanism, a ring-shaped article Heat of Against thermal deformation caused by the physical process, without increasing the number of steps of the manufacturing line of the ring shaped article, and can be the leveling without the cost and labor. It can also be applied to ring products of various sizes.

  An embodiment of the present invention will be described with reference to FIG. The deformation correction device 1 for a ring-shaped product includes an arrangement table 2 on which the ring-shaped product W is placed. A pair of receiving rolls 3 and a single pressure roll 4 are provided on the arrangement table 2. The receiving roll 3 is rotatably attached to a receiving roll support shaft 3 a that protrudes upward from the receiving roll support member 7. The pressure roll 4 protrudes upward from the pressure roll support member 11 and is attached so as to rotate integrally with a pressure roll support shaft 4 a that is rotatable with respect to the pressure roll support member 11. The ring-shaped product W is, for example, a bearing ring. The bearing ring of the bearing is formed by forging, and a raceway groove is formed on the inner peripheral surface or the outer peripheral surface by turning. The material of the bearing race is a steel material such as bearing steel.

  The upper surface of the mounting table 2 between the pair of receiving rolls 3 and one pressure roll 4 is a ring-shaped product placing portion 5, and one of the arrangement directions (Y direction) of the pair of receiving rolls 3. It is formed one step higher than the other from the end to the other end. The ring-shaped product placement portion 5 is formed with a notch 5a for avoiding interference with the pressure roll 4 and the pressure roll support member 11 described later when the pressure roll 4 described later advances. At the periphery of the arrangement table 2, a ring-shaped product W is loaded into the ring-shaped product mounting unit 5 from the direction of the arrow A and discharged from the ring-shaped product mounting unit 5 in the direction of the arrow B ( (Not shown) is provided.

  The pair of receiving rolls 3 can change the interval in the Y direction by a receiving roll interval changing mechanism 6. The receiving roll interval changing mechanism 6 includes the receiving roll support member 7, a guide 8 that guides the receiving roll support member 7 with respect to the arrangement table 2 so that the position of the receiving roll support member 7 can be changed in the Y direction, and the receiving roll support member 7. And fixing means 9 for fixing to. As the fixing means 9, for example, a bolt or a fixing tool that is fastened and fixed by frictional force can be used.

  The pressure roll 4 can be advanced and retracted in the direction connecting the intermediate point of the pair of receiving rolls 3 and the center point of the pressure roll 4 (X direction) by the pressure roll advance / retreat mechanism 10. The pressure roll advancing / retreating mechanism 10 includes a pressure roll support member 11 that rotatably supports the pressure roll 4 and a pair of guided portions 11a provided on the pressure roll support member 11 so as to be relatively movable. The X-direction guide shaft 12 and the advancing / retreating means 13 for advancing / retreating the pressure roll support member 11 with respect to the arrangement table 2 in the X direction. The guided portion 11a guides the guide shaft 12 by, for example, sliding guidance or rolling guidance. The advance / retreat means 13 is composed of, for example, a hydraulic cylinder.

  The pressure roll 4 is rotated in a predetermined direction by a pressure roll rotation drive mechanism 15. The pressure roll rotation drive mechanism 15 includes a rotation motor 16 installed on the pressure roll support member 11, a sprocket 17 attached to the output shaft of the rotation motor 16, and a sprocket 18 attached to the support shaft of the pressure roll 4. A chain 19 is wound around the chain.

  An oil tank 20 for cooling the ring-shaped product is installed below the ring-shaped product mounting portion 5 of the arrangement table 2, and the ring-shaped product on the ring-shaped product mounting portion 5 is contained in the quenching oil of the oil tank 20. W can be immersed. The deformation correction cooling mechanism 21 for that purpose tilts the placement table 2 supported by the support means 22 and the support means 22 that supports the placement table 2 so that the placement table 2 can be tilted so that the ring-shaped product placement unit 5 side is down. The tilting means 23 is used. In this embodiment, the support means 22 is configured such that a horizontal inclined central shaft 22a protruding outward from both sides in the Y direction of the arrangement table 2 is rotatably supported by a rotation support member 22b. Further, the tilting means 23 is composed of a hydraulic cylinder provided between the lower surface of the arrangement table 2 and the floor surface 24 located on the opposite side of the ring-shaped product placement portion 5 with respect to the tilt center shaft 22a. As shown by a solid line in FIG. 1B, the ring-shaped product W on the ring-shaped product mounting portion 5 is immersed in the oil in the oil tank 20 by driving the tilting means 23 and tilting the arrangement table 2. .

  The ring-shaped product deformation correction apparatus 1 is provided in the quenching apparatus shown in FIG. The quenching device 30 includes a heating unit 31, a primary cooling unit 32, a secondary cooling unit 33, a cleaning unit 34, and the like. The heating unit 30 heats the ring-shaped product W to a predetermined quenching temperature (for example, 850 ° C.) using a heating furnace or the like. The primary cooling unit 32 immerses the ring-shaped product W heated to the quenching temperature in the quenching oil in the primary cooling bath 32a, and primarily cools the ring-shaped product W to a temperature (for example, 290 ° C.) higher than the martensite transformation point. The secondary cooling unit 33 immerses the primarily cooled ring-shaped product W in the quenching oil of the oil tank 20 while correcting the deformation by the deformation correcting device 1, and performs secondary cooling to a certain temperature (for example, 110 ° C.). . The cleaning unit 34 cleans the secondary cooled ring-shaped product W and sends it to the subsequent process.

In this embodiment, the primary cooling tank 32a of the primary cooling section 32 has a U-shaped cross-section at the portion containing quenching oil, and the other end from the introduction section 32aa that is one end of the U-shape. The ring-shaped product W is conveyed by the elevator 32b to the discharge part 32ab which is an end part. Space 32c of the upper of the introduction portion 32aa is a sealed space filled with nitrogen gas N _2. An openable / closable door 32 d is provided between the space 32 c and the heating unit 31. For According to the configuration of the primary cooling bath 32a, the ring shaped article W heated by the heating unit 31, which is placed in the space 32c filled immediately with nitrogen gas N _2, followed by a dip in a quenching oil, Cooling can be performed without exposure to the atmosphere.

  Deformation correction by the deformation correction device 1 in the secondary cooling unit 33 will be described. The deformation correction device 1 stands by at a retracted position P <b> 1 where the pressure roll 4 is retracted with respect to the receiving roll 3 as indicated by a chain line in FIG. 1. At this time, the arrangement table 2 is in a horizontal state. The ring-shaped product W coming out of the primary cooling tank 32a is loaded into the ring-shaped product mounting portion 5 of the deformation correction device 1 in the standby state by a loading / discharging mechanism (not shown). When the ring-shaped product W is inserted, as shown by a solid line in FIG. 1, the advancing / retreating means 13 of the pressure roll advance / retreat mechanism 10 is driven to advance the pressure roll 4 to the advance position P2. As a result, the ring-shaped article W is sandwiched between the pair of receiving rolls 3 and one pressure roll 4 from both sides in the X direction. In this state, the rotary motor 16 of the pressure roll rotation drive mechanism 15 is driven to rotate the pressure roll 4 in a predetermined direction. The ring-shaped product W is rotated between the rolls 3 and 4 while being sandwiched between the pair of receiving rolls 3 and the pressure roll 4 from both sides with a predetermined load, so that the deformation is corrected and the roundness is improved. Rise.

  Also, before and after the deformation correction is started, that is, before and after the pressure roll 4 starts rotating, the tilting means 23 of the deformation correction cooling mechanism 21 is driven as shown by the solid line in FIG. The placement table 2 is tilted so that the ring-shaped product placement portion 5 is on the lower side. Thereby, the ring-shaped article W is immersed in the quenching oil of the oil tank 20, and is secondary-cooled. Since the insertion of the ring-shaped product W into the ring-shaped product placement unit 5, the advancement of the pressure roll 4, the rotation of the pressure roll 4, and the tilting operation of the arrangement table 2 are performed continuously, primary cooling and two Subsequent cooling takes place with little time. Therefore, quenching is performed well.

Temperature of the ring-shaped article W at the time of starting the deformation correction is to not 20 ° C. than the martensite varying state point temperature to 50 ° C. higher temperatures. Here, the time for performing deformation correction is the time from the start of pressing the pressure roll 4 to the end of pressing. The time for performing deformation correction is about 40 seconds to 90 seconds. When the ring-shaped product W having the above temperature is immersed in the quenching oil of the oil tank 20 for the above-mentioned time, the ring-shaped product W is cooled to a cooling target temperature (for example, 110 ° C.) of the secondary cooling. Therefore, deformation correction and secondary cooling are performed without time waste. When the deformation correction and the secondary cooling are completed, the arrangement table 2 is returned to the horizontal position, the rotation of the pressure roll 4 is stopped, the pressure roll 4 is moved back to the retreat position P1, and the ring-shaped product W is released. The released ring-shaped product W is discharged out of the placement table 2 from the ring-shaped product placement portion 5 of the placement table 2 by an input / discharge mechanism (not shown).

In the ring-shaped article deformation correcting device 1 having this configuration, the pressure roll 4 can be moved back and forth, so that the distance between the pair of receiving rolls 3 and the pressure roll 4 can be freely changed. Therefore, it can be applied to ring-shaped products W having various diameters. The interval between the pair of receiving rolls 3 may be changed by the receiving roll interval changing mechanism 6 according to the size of the ring-shaped product W.
The deformation correction of the ring-shaped product by the deformation correction device 1 does not use a constraining mold, so that a mold cost is not required, and the labor for fitting the ring-shaped product W into the mold or removing the mold from the mold is not required. In addition, since the deformation correction apparatus 1 performs deformation correction in the quenching cooling process, the deformation correction apparatus 1 can be installed without increasing the number of steps in the production line.

  A test was conducted to confirm the effect of deformation correction by the deformation correction apparatus 1. For the test, a bearing steel, an outer diameter of 280 mm, an inner diameter of 250 mm and a wall thickness of 15 mm was used. With respect to this ring-shaped product, the primary cooling pulling temperature and the pressure load of the pressure roll 4 were changed in stages, and the outer diameter change amount ΔD and the wall thickness change amount ΔT were measured. The outer diameter change amount ΔD is the difference between the outer diameter D1 before deformation correction B and the outer diameter D2 after deformation correction A (FIG. 3). The thickness change amount ΔT is the difference between the thickness T1 before deformation correction B and the thickness T2 after deformation correction A (FIG. 4). An average value x, a standard deviation value σ, and a maximum value Max were determined for each of the outer diameter change amount ΔD and the wall thickness change amount ΔT. Table 1 shows the test results.

From the test results, the following was found.
(1) Regarding the outer diameter change ΔD, good results were obtained when the primary cooling pull-up temperatures were 250 ° C. and 280 ° C. and the pressure load was 300 kgf. Also, good results were obtained when the primary cooling pulling temperature was 280 ° C. and the pressure load was 580 kgf.
(2) Regarding the wall thickness change ΔT, when the primary cooling pull-up temperature is 230 ° C., 250 ° C., and 280 ° C., and the pressurization load is 150 kgf, the primary cooling pull-up temperature is 250 ° C. and 280 ° C. When the load was 300 kgf, good results were obtained in each of the cases where the primary cooling pulling temperature was 230 ° C. and the pressure load was 580 kgf.
(3) From this, good results can be obtained for both the outer diameter change amount ΔD and the wall thickness change amount ΔT when the primary cooling pull-up temperatures are 250 ° C. and 280 ° C. and the pressurizing load is 300 kgf. I found out.

(A) is a top view of the deformation correction apparatus concerning embodiment of this invention, (B) is the front view. It is a figure which shows the conceptual structure of the hardening apparatus provided with the same deformation correction apparatus. It is explanatory drawing of the outer diameter variation | change_quantity of a ring-shaped goods. It is explanatory drawing of the thickness change amount of a ring-shaped article, and the IVB-IVB sectional view of the figure (A) is the figure (B). It is explanatory drawing which shows the method of the conventional deformation correction.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Deformation correction apparatus 2 ... Arrangement | positioning stand 3 ... Reception roll 4 ... Pressure roll 5 ... Ring-shaped article mounting part 6 ... Reception roll space | interval change mechanism 10 ... Pressure roll advance / retreat mechanism 15 ... Pressure roll rotation drive mechanism 20 ... Oil tank 21 ... Cooling mechanism 22 during deformation correction ... Support means 23 ... Tilting means W ... Ring-shaped product

Claims (7)

A ring-shaped product deformation correction device that corrects deformation while cooling a heated ring-shaped product, and a placement table on which the heated ring-shaped product is placed, and an outer peripheral surface of the ring-shaped product on the placement table. a pair of receiving rolls to rollably contact, provided opposite through a receiving roll distance changing mechanism for changing the distance between the pair of receiving rolls, the ring shaped article to the one pair of receiving rolls 1 A pressure roll, a pressure roll advance / retreat mechanism for moving the pressure roll forward and backward to a forward position pressed against the outer peripheral surface of the ring-shaped product and a retracted position away from the outer peripheral surface; deformation correcting device of the ring-shaped article, characterized in that it comprises a pressure roll rotation driving mechanism including a rotating motor for the pressure roll pressed against the ring-shaped article rotating driven by a mechanism. 2. The receiving roll interval changing mechanism according to claim 1 , wherein the receiving roll interval changing mechanism includes a receiving roll supporting member that supports each receiving roll, a guide that guides the receiving roll supporting member with respect to the arrangement table, and the receiving roll. A fixing means for fixing the support member to the arrangement table, and the pressure roll rotation drive mechanism includes the rotation motor installed on the pressure roll support member that supports the pressure roll, and the rotation motor a sprocket mounted to the output shaft and the pressure roll support shaft,-rings shaped article deformation correcting device having a wound a chain to sprockets.   The deformation correction apparatus for a ring-shaped product according to claim 1 or 2, wherein the time for performing deformation correction by pressing the pressure roll against the outer peripheral surface of the ring-shaped product is 40 seconds to 90 seconds. In any one of claims 1 to 3, the temperature of the ring-shaped article at the time of starting the deformity correction the presses the pressure roller on the outer peripheral surface of the ring-shaped article, from martensite varying state point temperature Deformation device for ring-shaped products that is 20 to 50 ° C higher.   5. The ring according to claim 1, further comprising: a cooling oil tank; and a deformation correction cooling mechanism that cools the ring-shaped product by immersing it in the quenching oil of the oil tank during the deformation correction. Deformation straightening device.   The deformation correction cooling mechanism according to claim 5, wherein the deformation correction cooling mechanism supports the arrangement table so as to be tiltable so that a ring-shaped product placement portion on which the ring-shaped product of the arrangement table is placed is on the lower side. An apparatus for correcting deformation of a ring-shaped product, comprising tilting means for tilting the placement table supported by the support means, wherein the ring-shaped product is immersed in the quenching oil of the oil tank by tilting the placement table by the tilting means.   The deformation correction device for a ring-shaped product according to any one of claims 1 to 6, wherein the ring-shaped product is a bearing ring.

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