JP2913182B2 - Partial quenching device for steel ring - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a partial quenching apparatus for a steel annular body, and more particularly, to an apparatus in which an outer diameter surface is in direct sliding contact with a mast member such as a mast roller / bearing. Apparatus for partially quenching an annular body whose quenching layer on the radial side needs to have a lower hardness than the quenching hardened layer on the inner diameter side, and for simultaneously processing at least two annular bodies in one quench About.

(Prior Art) The present applicant has disclosed Japanese Patent Application Laid-Open No.
As described in JP-B-163706 and JP-A-55-31102, as a device for implementing the same, a structure in which a cooling medium is injected at least to the inner and outer diameter surfaces of two annular bodies stacked vertically is adopted. An apparatus was provided for treating two toroids in a single quench. This double quenching apparatus has the advantage of increasing productivity in that it can perform double processing in one lot, but in any of the prior inventions, the inner side cooling liquid of the upper annular body impinges on the inner surface. After that, it falls directly below or diagonally downward, and this violently intersects with the horizontal injection of the coolant on the inner diameter side of the lower annular body, making the desired jet flow irregular, and as a result, the inner annular surface of the upper annular body and the lower side It has been found that there remains a problem of producing a quenching error (deviation) between the inner surface of the annular body and the inner surface of the annular body. There are various other types of partial quenching devices for such annular bodies, and all of them are devices that form a line-symmetrical quenching layer for a single annular body, all of which simultaneously partially quench a stacked annular body. Is absent except for the applicant.

(Problems to be Solved by the Invention) The object of the present invention is, therefore, to extend the partial quenching apparatus of the above-mentioned technical background, and the drop of the upper inner diameter side cooling liquid is reduced to the lower inner diameter side. It is an object of the present invention to provide a device that does not hinder the horizontal jet flow of the cooling liquid and has less variation in quenching of the inner diameter surfaces of the upper and lower annular bodies. In the present invention, the quenched and hardened layer at the stepped contact surface is shallow and does not extend to the contact surface. However, there is no particular problem in the use of the annular body (the hard quenched layer is formed on one side). (It does not have to be exposed on the end face but on the opposite end face).

(Means for Solving the Problems) The general concept of the present invention for achieving the above object is to divide a cooling zone for cooling the inner diameter surfaces of the upper and lower annular bodies into upper and lower parts separately, and to collect a total amount of the cooling liquid impinging on the upper annular body surface. Measures to prevent any interference with the lower coolant injection, and to provide separate drainage paths for the upper and lower coolants, and for the inner diameter surface of the stepped portion, both upper and lower annular bodies Two points are to take measures to prevent the injection of the cooling liquid.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of the present invention will be described below with reference to the drawings of a preferred embodiment; FIG. 1 is a partially cutaway front view showing an embodiment of the apparatus of the present invention, and FIG. FIG. 3 is a plan view, FIG. 3 is an explanatory view showing a quenched layer of an annular body obtained by the apparatus, FIG.
The figure shows a sectional hardness distribution diagram of the quenched layer.

As can be seen from the drawing, the present invention includes upper and lower partition members 30, which contact the upper and lower outer peripheral surfaces of at least two steel annular bodies 1, 2 which are heated to the quenching temperature and vertically stacked coaxially. Four
Upper and lower chuck means 3, 4 provided with zero and said set of annular bodies
A pair of upper and lower inner diameter side cooling nozzles 5, 6 arranged on the inner diameter side so that the coolant can be jetted onto the inner peripheral surfaces of each of 1, 2;
A coolant receiving member 7 disposed between the upper and lower inner diameter cooling nozzles 5 and 6 for receiving the coolant that has been injected from the upper inner diameter cooling nozzle 5 to the upper inner peripheral surface; Partial quenching of a steel annular body comprising: a drainage pipe 8 connected to the outer ring 7; and outer diameter side cooling nozzles 9 and 10 for injecting compressed air or mist to the outer peripheral surfaces of the stepped annular bodies 1 and 2. Related to the device.

In the above description, the upper and lower partition members 30 and 40 are for imparting different cooling effects to the annular bodies 1 and 2 to partition the annular bodies 1 and 2 into an inner diameter side and an outer diameter side.

(Example) The steel annular bodies 1 and 2 may be either bearing steel (SUJ type) or carbon steel for general structure (SC type). A typical product is a bearing that also serves as a mast roller of a forklift. A quench hardened layer (HRC60) is formed on the end face that is in sliding contact with the inner surface of the ball and a non-hardened hardened layer (HRC40-20) is formed on the outer circumferential surface that is in contact with the inner circumferential surface of the mast. (Detailed sectional hardness distribution will be described later). Upper and lower chuck means
Reference numerals 3 and 4 form a stepped annular body, which can be moved up and down by a lifting mechanism (not shown). The lower chuck means 4 is rotated by a rotating mechanism (not shown), and the upper chuck means 3 follows. Rotate.

The upper and lower cooling nozzles 5, 6 are formed by separate perforated cylinders 11, 11 'so that they can move integrally with the chuck means 3, 4 in a double pipe structure, and each has a cooling liquid supply pipe.
It is connected to a cooling liquid supply source (not shown) via 12, 12 '.

An annular coolant receiving (dish) member 7 having a cylindrical outer peripheral wall 70 is mounted on the top of the lower cooling nozzle 6, and this member 7 is connected to a drain passage 8 disposed inside a coolant supply pipe 12 '. It is connected to the. With this configuration, the cooling liquid 50 hit against the inner surface of the annular body 1 by the upper cooling nozzle 5 and kicked off is discharged from the member 7 to the drain passage 8.
Is discharged out of the system. On the other hand, the cooling liquid 60 hit against the inner surface of the annular body 2 by the lower cooling nozzle 6 and kicked off is the main pipe 13 connected to the lower portion of the lower chuck means 4 and the cooling liquid supply pipe.
It is discharged out of the system from the annular cavity 14 formed between the space 12 '. Coolant (water, etc.) sent into perforated cylinders 11, 11 '
Are injected in a substantially horizontal direction from the injection holes 111, 111 'of the peripheral body to form the upper and lower cooling nozzles 5, 6, respectively. The height of the outer wall 70 is such that the coolant 50 that has rebounded against the inner surface of the annular body 1 is the coolant.
Do not interfere with the hardenability of the annular body 2 by intermingling with 60 (although there is no injection hole at the corresponding location of the cylindrical body 11).
It is adjusted so as to be close to and cover the cross-section part a. The outer diameter side cooling nozzles 9 and 10 surround the outer sides of the stepped annular bodies 1 and 2 and supply compressed air or mist (a mixture of air and water) from the ejection ports 90 and 100 simultaneously with the inner diameter side cooling nozzles 5 and 6. Inject.

(Operation) In the above configuration, the lower chuck means 4 and the lower cooling nozzle 6
The steel annular bodies 1 and 2 heated to the quenching temperature by a heating device (not shown) are loaded into a place where is set in the state of FIG. 1, and the lower annular body 2 is seated on the lower partition member 40. The annular bodies 1 and 2 are double-stacked on the lower chuck means 4, and then the upper chuck means 3 descends together with the upper cooling nozzle 5 and the upper partition member 30.
The upper annular body 1 is chucked downward from above by
Set at a predetermined position as shown in the figure. Subsequently, the drive rotation of the lower chuck means 4 and the driven rotation of the upper chuck means 3 start, and at the same time, the injection of the cooling liquid from the upper and lower cooling nozzles 5, 6 and the compressed air or mist from the outer diameter side cooling nozzles 9, 10 Injection proceeds to cool both inner and outer diameters simultaneously. After the coolant from the upper cooling nozzle 5 hits the inner surface of the annular body 1, the coolant is immediately received by the coolant receiving member 7 and intersects with the jet of the coolant 60 from the lower cooling nozzle 6. The coolant 50 that is prevented from obstructing the flow and is received is discharged out of the system through the drain pipe 8. On the other hand, the lower annular body 2 from the lower cooling nozzle 6
The coolant 60 that has bounced off by hitting the inner diameter surface of the coolant is discharged from the annular cavity 14, and thus the coolants 50, 60 involved in vertical cooling.
Are eliminated along a separate and independent discharge path without any interference. The height of the outer surrounding wall 70 of the receiving member 7 is set so that the coolant 50 which has hit against the inner surface of the annular body 1 and rebounds does not intersect with the coolant 60 and hinder the hardenability of the annular body 2 (mostly, the cylindrical body 11).
Although the injection hole is not present at the corresponding position (1), it is adjusted so as to approach and cover the cross-section area a. After the quenching is completed, the rotation of the upper and lower chuck means 3 and 4 is stopped, and then the lower chuck means 3
Rises together with the upper cooling nozzle 5 and subsequently discharges the annular bodies 1 and 2 out of the system by a carrier (not shown). This gives 1
By the quenching process, partial quenching of the two annular bodies 1 and 2 is completed.

FIG. 3 shows the distribution of the quenched layer according to the present invention. The left end face in the figure corresponds to the upper and lower stacking part a, and the right end face is the annular body 1 in FIG.
Upper free end face (or the lower free end face of the annular body 2). The quench hardened layer a on the inner diameter side is exposed on the free end face and has a wide range extending into the outer diameter side, but does not reach the end face at the stepped portion a. This is because the application of the cooling liquids 50 and 60 is prevented to the stepped portion a. The non-quenching hardened layer b on the outer diameter side is exposed on the entire surface of the stepped portion a and ends at the corner at the free end surface. FIG. 4 shows the relationship between the hardness and the depth of the hardened layers (a) and (b) (cross-sectional hardness distribution). It can be seen from the figure that the hardened hardened layer a has a maximum HRC of about 60 and the non-hardened hardened layer B has an HRC of about 30.

In the present apparatus, the rebound of the cooling liquid 50 of the upper cooling nozzle 5 does not interfere with the injection of the cooling liquid 60 from the lower cooling nozzle 6, so that the cooling and hardening of the inner diameter surfaces of the upper and lower annular bodies 1 and 2 are uniformly maintained. It will be well understood that a uniform product which does not cause sagging and quenching is obtained.

The above has described only one embodiment of the apparatus of the present invention, and the present invention is not limited thereto. For example, a three-stage or four-stage product can be used instead of a two-stage product of an annular body. Further, the upper cooling nozzle 5 may be provided on the upper chuck means 3 side.

(Effect of the Invention) As is clear from the description above, the apparatus of the present invention is concerned with partial quenching of an annular body having at least a two-stage product by causing the upper coolant to interfere with the lower coolant, which has conventionally been a problem. A uniform quenched layer can be obtained without adversely affecting the cooling effect, productivity can be improved by a plurality of processes, a cooling liquid receiving member is provided between the upper and lower cooling nozzles, and a separate drain passage is provided for the receiving member. Achieved accurate drainage with a compact structure due to the formation in connection with the above, and abolished hard quenching of this part that has no significance in the use in the stepped part by the surrounding wall of the receiving member By doing so, it is possible to reduce the trouble of quenching management.

[Brief description of the drawings]

FIG. 1 is a front view of a partially cutaway longitudinal section showing an embodiment of the apparatus of the present invention, FIG. 2 is a plan view of a cooling liquid receiving member, and FIG. 3 is an illustration showing a quenched layer of an annular body obtained by the apparatus. FIG. 4 shows a sectional hardness distribution diagram of the quenched layer. (Explanation of reference numerals) 1,2: steel annular body, 3: upper chuck means, 4, lower chuck means, 30, upper partition member, 40 lower partition member,
5 ... upper cooling nozzle, 6 ... lower cooling nozzle, 50 ... upper cooling liquid, 60 ... lower cooling liquid, 7 ... cooling liquid receiving member, 70 ...
Outer surrounding wall, 8: drainage pipe, 14: annular cavity, a: stepped portion, a ... inner quenching hardened layer, b ... outer non-quenching hardened layer.

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. ⁶ , DB name) C21D 9/00-9/44 C21D 9/50 C21D 1/18 C21D 1/62-1/673

Claims (3)

(57) [Claims] 1. Upper and lower chucks provided with upper and lower partition members which respectively contact upper and lower outer peripheral surfaces of at least two steel annular bodies which are heated to a quenching temperature and vertically stacked coaxially. Means, a pair of upper and lower inner diameter cooling nozzles arranged on the inner diameter side so as to be capable of jetting a coolant on the inner peripheral surface of each of the pair of annular bodies, and disposed between the upper and lower inner diameter cooling nozzles. A cooling liquid receiving member for receiving the cooling liquid injected from the upper inner diameter side cooling nozzle to the upper inner peripheral surface, a drain pipe connected to the cooling liquid receiving member, and compressed air on the outer peripheral surface of the annular body Alternatively, a partial quenching device for a steel annular body, comprising an outer diameter side cooling nozzle for injecting mist. 2. The apparatus according to claim 1, wherein the outer peripheral surface of the stacked annular body with which the upper and lower partition members abut is an arc-shaped chamfer. 3. The upper and lower inner diameter side cooling nozzles are formed separately by a perforated cylindrical body, and the upper end of the upper inner diameter side cooling nozzle and the lower end of the lower inner diameter side cooling nozzle are connected to a cooling liquid supply pipe, respectively. The coolant receiving member is fixed to the upper end of the lower inner side cooling nozzle with a cylindrical outer peripheral wall having an upper opening, and the drain pipe is connected to the bottom of the coolant receiving member to supply the coolant. The cooling liquid injected into the inside of the pipe and injected from the upper cooling nozzle to the upper peripheral surface of the annular body is received by the cooling liquid receiving member and discharged from the drainage pipe, and is discharged from the lower cooling nozzle to the lower peripheral surface of the annular body. 2. The apparatus according to claim 1, wherein the injected coolant is discharged from a space outside the coolant supply pipe.