JPH0332513Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The disclosed technology belongs to the technical field of hardening the sliding portion of a cylindrical workpiece of a mechanical device component by hardening the surface thereof.

Therefore, this invention is a surface hardening treatment device that hardens the surface of a constant velocity joint of an automobile, such as a roller sliding portion of a cylindrical member, and hardens the hardened surface of a workpiece. The quenched water sprinkler is integrally joined to the other side, and the quenched coil is integrally joined to form one unit, and a predetermined number of units are arranged in the longitudinal direction, so that the quenched water sprinkler is quenched. This is a device for surface hardening of workpieces in which an incoming water jetting nozzle is provided at an angle to the hardened surface of the workpiece. In particular, the nozzle is installed on the surface of the hardened water sprinkler facing the hardened surface of the workpiece. at least one is formed, and
This invention relates to a surface hardening treatment device for a workpiece, which is formed to be inclined in the longitudinal direction and distributed in the opposite direction to the center of the workpiece toward the hardening surface.

<Prior art> As is well known, mechanical equipment parts have parts that slide relative to each other under high pressure, and these parts need to have sufficient wear resistance. Since precision and smoothness is required, there are surface hardening treatments as a technique to deal with this, and among these, quenching treatment is widely adopted.

Although such hardening treatment technology has been used for a long time, recently high-frequency induction heating methods have been used to improve work efficiency, reduce man-hours, and improve processing accuracy. A mode in which cooling is carried out by spraying quenching water from a nozzle of a quenching water sprinkler attached to the quenching coil immediately after heating and quenching has become popular.

As an example of a workpiece to be surface hardened,
For example, there are constant velocity joints in automobiles, and the performance requirements for these parts include wear resistance and torsional strength.

Therefore, in constant velocity joints, quenching is applied to the surface hardening of the ball sliding parts and shaft parts. Briefly,
In the embodiment shown in FIG. 8, a surface hardening treatment device 2 is inserted concentrically into the workpiece 1 of the constant velocity joint, and a predetermined number of stages of hardening coils 3 in the longitudinal direction (four stages in FIG. 8) are formed. 3..., a quenching water sprinkler 4 is installed inside them, the workpiece 1 is heated and quenched by each quenching coil 3, and then, from the nozzle of the quenching water sprinkler 4, each quenching coil 3, 3 is heated and quenched. Quenching water 5 was jetted out from between the holes to harden the steel.

<Problem to be solved by the invention> In this embodiment, each quenching coil 3 is provided close to the quenching surface 6 of the workpiece 1, and behind the quenching coil 3,
In other words, since the quenching water sprinkler 4 is installed on the rear side and sprays quenching water 5 from between each quenching coil 3, the heating efficiency of quenching is good, but the hardening process of the workpiece is The induced current tends to concentrate between the hardened coils 3, especially in the central part in the axial direction, and in particular, there is a high current density area where the clearance of the hardened coil 3 is small, resulting in a large hardening depth. There is a drawback that the distortion in hardening becomes large, and from this point, quenching unevenness such as so-called troostite is likely to occur.Also, since the quenching water 5 is ejected from the back of the quenching surface 6, that is, from the inside, By being ejected perpendicularly to the treated surface 6, the quenching water 5 becomes stagnant on the treated surface 6 and does not flow out smoothly, resulting in uneven cooling. The negative points were that the quenching hardness of 100% could not be obtained, and wear and impression formation occurred.

As a result, there were problems in that the hardness varied depending on the axial position of the processing surface 6, and the amount of lateral torsional deformation of the workpiece was not smooth and became large.

On the other hand, a surface hardening treatment device 2′ as shown in FIG.
In this case, the quenching coil 3 and the quenching water sprinkler 4 are integrally connected, and the quenching water sprinkler 4, which has many nozzles, faces the processing surface 6 of the workpiece 1. The shape is such that the quenching water 5 gushes out from the quenching coils 3, and the quenching water 5 tends to stagnate in the center of the quenching surface 6 between the quenching coils 3 as in the above-mentioned embodiment. , Due to the large number of nozzles, stagnation is likely to occur, and quenching unevenness such as troostite is likely to occur.
Furthermore, there is a disadvantage that deformation distortion such as lateral twisting cannot be avoided.

In both of the above-mentioned embodiments, the degree of freedom in the quenching conditions is narrow, and proper setting requires a lot of adjustment time, and skill is required, resulting in poor work efficiency. It was hot.

As a result, the product precision of the workpiece was not improved to the desired degree, and there were problems in that it was difficult to obtain wear resistance as designed.

Also, for example, the applicant's earlier application JP-A-58-144416
As shown in the above publication, there is a technique in which the number of nozzles of the quenching water sprinkler is reduced to prevent quenching water from stagnation on the quenching surface of the workpiece, but in this technique, the nozzles are connected to the quenching water sprinkler. Because it is installed obliquely at the bottom of the housing, it is not possible to shorten the distance to the hardened surface of the workpiece.
I was concerned that the cooling function could not be fully demonstrated.

The purpose of this invention was to solve the technical problem of the surface hardening treatment device having a hardened coil and hardened water sprinkler based on the above-mentioned conventional technology, and to achieve high product accuracy while maintaining sufficient wear resistance. We would like to provide an excellent surface hardening treatment device for workpieces that is easy to secure, easy to set hardening conditions, improves work efficiency, and is easy to manage. It is something to do.

<Means for solving the problem> In order to solve the above-mentioned problem, the structure of this invention, which is based on the scope of the above-mentioned utility model registration claim, is to solve the above-mentioned problem. The quenching water sprinkler on the quenching surface side set in multiple stages in the axial direction and the quenching coil on the opposite side are connected, and the nozzle of the quenching water sprinkler is installed at an angle with respect to the quenching surface of the workpiece. In the surface hardening treatment device for a workpiece, at least one nozzle provided on a surface of the quenching water sprinkler opposite to the quenching surface of the workpiece is inclined with respect to the quenching surface of the workpiece. This is a surface hardening treatment device for a workpiece, in which the inclinations of the nozzles of the quenching water sprinklers in each stage are distributed in opposite directions relative to the center in the longitudinal direction of the workpiece.

<Function> Therefore, the surface hardening treatment device is a compact joint type of a quenching coil and a quenching water sprinkler, with predetermined multiple stages in the longitudinal direction, and the quenching water sprinkler is placed facing the quenching surface of the workpiece. so that the quenching water is spouted from the nozzle onto the quenched surface.
Therefore, at least one nozzle for injecting quenching water provided on a surface of the quenching water sprinkler opposite to the quenching surface of the workpiece is distributed in a direction opposite to the center of the workpiece in the longitudinal direction, and is arranged in a predetermined direction. The quenching water spouted out smoothly flows out on the quenching surface and does not stagnate, so that the quenching effect is good and the heating efficiency is improved.
Technical measures have been taken to improve the quenching efficiency, thereby preventing uneven quenching and improving product precision.

<Example> Next, an example of this invention will be described below based on FIGS. 1 to 7. Note that the same parts as in FIGS. 8 and 9 will be described using the same reference numerals.

In the embodiment shown in FIGS. 1 and 2, 2'' is a surface hardening treatment device which constitutes the gist of this invention, and is inserted and set concentrically into a constant velocity joint 1 of an automobile as a workpiece. The work 1
quenched water sprinkler 4' for the quenched surface 6 of
It is an integrally joined type in which the hardening coils 3 are provided on the back side, that is, on the rear side, and the hardening coils 3 are arranged in four stages in the longitudinal direction of the workpiece 1. 3, 3... and quenched water sprinklers 4', 4'... are set.

In this embodiment, one nozzle for injecting quenching water 5 is provided at each corner of the surface facing the quenching surface 6 of each quenching water sprinkler 4' arranged in one row in the longitudinal direction. 7 is provided to shorten the distance to the quenched surface and to fully exert its cooling capacity, and as shown in FIG. 2, it has an inclination angle of θ with respect to the axial direction of the workpiece 1. Quenching water 5
The hole is machined so that it does not directly collide orthogonally with the hardened surface 6, that is, so that it flows out smoothly in the axial direction, and the inclined direction is perpendicular to the hardened surface 6.
The quenching water 5 is distributed in opposite directions symmetrically with respect to the center of the quenching water 5, so that the quenching water 5 flows out more smoothly and is prevented from stagnation.

In this way, by reducing the total number of nozzles 7 of each quenching water sprinkler 4' and forming the holes in an inclined manner, as shown in FIG. (not shown for convenience of illustration), if the conventional form does not involve machining a small number of inclined nozzle holes, the horizontal axis represents the induced current, and the vertical axis represents the axis of the workpiece 1, as shown in B. Considering the length in the direction, the distribution of induced current on the hardened surface 6 is such that high frequency current tends to flow between the hardened coils, so if the clearance between the hardened coils is small, parts with high current density will occur. As a result, a large and uneven distribution occurred between each quenching water sprinkler 4, which caused quenching unevenness such as troostite. However, in this design, as shown in B', It can be seen that the current distribution is clearly smoothed.

Furthermore, as shown in FIG. 2, since the nozzle 7 is inclined at a predetermined angle θ with respect to the quenched surface 6, the quenched water 5 collides orthogonally with the quenched surface 6. Therefore, the cooling effect is good by smoothly flowing through without stagnation, and therefore, quenching unevenness such as troostite does not occur.

The inclination angle θ of the nozzle 7 is designed to be shallower toward the center of the workpiece 1 and larger toward the distance from the center (distributed symmetrically in the opposite direction to the center of the hardened surface). should be determined appropriately based on theory and experimental data.

In that case, the quenching conditions should be such that the average heating distribution and cooling efficiency are achieved.

In the above configuration, the surface hardening treatment device 2'' is set on the workpiece 1, and each quenching coil 3 is energized to heat and harden the workpiece 1. After that, quenching water is supplied from each nozzle 7 of the quenching water sprinkler 4'. When the quenching water 5 is jetted out and cooled as shown by the arrow in FIG. ), the water flows smoothly and actively in the longitudinal direction without stagnation on the hardened surface 6 of the workpiece 1, and also faces the hardened surface 6 of the hardened water sprinkler 4'. Since the nozzle 7 is provided on the surface to be quenched, the distance between the quenching water and the quenching surface 6 is short, and a sufficient cooling effect is achieved. The input accuracy is as designed, at least
Achieved very close to design.

In this case, since the nozzle 7 of each quenching water sprinkler 4' is inclined at a predetermined angle in the length direction, and only one nozzle 7 is formed in each quenching water sprinkler 4', and as described above, the quenching process Since the distribution of the induced current generated on the surface 6 is smoothed as shown in FIG. 5B', these factors combine to prevent uneven hardening, and the heating efficiency is extremely high.

Furthermore, since the heating distribution and cooling distribution are uniform, the product accuracy is also good.

According to the experimental data, as shown in Fig. 6, the amount of deformation due to radial strain is shown in graph C in the conventional mode, where the vertical axis represents the deformation μ and the horizontal axis represents the axial displacement mm of the workpiece. Similarly, when the axial position of the workpiece deviates from the center position, the amount of deformation μ changes considerably, but in this invention, it is found that it is smoothed out as shown in the graph C'.

Regarding hardness, as shown in Fig. 7, if we take the hardness Hv (10Kg) on the vertical axis and the axial position mm from the center of the workpiece on the horizontal axis, in the conventional mode, graph D is obtained. As shown in graph D', the hardness of the product with changes becomes almost flat in this design, as shown in graph D'.As can be seen from both data, the product accuracy is improved in this design. It can be seen that the wear resistance and torsion resistance of the constant velocity joint are improved.

In addition, in the embodiment shown in FIG. 3, hardened coils 3, 3, 3 with three turns (the same applies if there are less than three turns) are connected to the corresponding hardened water sprinklers 4', 4', 4'. In this embodiment, a pair of nozzles 7, 7 inclined in opposite directions are provided on the surface of the quenching water sprinkler 4'' located at the center of the workpiece 1 on the quenching surface 6 side to sprinkle quenching water. 5 is not ejected perpendicularly to the hardened surface 6 of the workpiece 1, but easily flows in the longitudinal direction as in the above-mentioned embodiment. Therefore, the cooling efficiency is improved, and the distribution of induced current is also smoothed. It was designed so that

Further, the embodiment shown in FIG. 4 has hardened coils 3, 3
In this embodiment, the quenched water sprinkler 4'' at the center of the workpiece 1 has a pair of nozzles as in the case of the 3-volume sprinkler (below) shown in Fig. 3 above. 7,
7 is installed at a predetermined inclination angle, and the quenched water sprinklers 4' and 4' above and below each have only one nozzle 7 installed at an inclination, but the effect that they produce is essentially different. It's something that doesn't exist.

Therefore, in the surface hardening treatment equipment to be set, the quenching water sprinkler 4'' located at the center of the workpiece 1 has a pair of nozzles 7 facing the quenching surface 6, and the quenching water sprinklers above and below Only one nozzle 7 is provided for each of 4' and 4' to ensure that the quenching water 5 from the nozzle 7 does not collide perpendicularly with the quenching surface 6 of the workpiece 1. sprayed at an angle,
It is sufficient to allow it to flow smoothly without stagnation.

It goes without saying that the embodiments of this invention are not limited to the above-mentioned embodiments, and various embodiments can be adopted.

<Effects of the invention> As described above, according to this invention, basically, in an apparatus that performs surface hardening treatment on cylindrical workpieces, etc., the quenching coil and the quenching water sprinkler are integrally joined, and the quenching coil and the quenching water sprinkler are integrally connected, and the quenching coil and the quenching water sprinkler are integrated into a multi-stage structure in the longitudinal direction. At least one of the nozzles of the quenching water sprinkler set and facing the quenching surface of the workpiece has a predetermined inclination angle distributed in the opposite direction to the longitudinal center on the side facing the quenching surface. Firstly, the distribution of induced current generated on the hardened surface of the workpiece is smoothed, and secondly, the quenching water is not collided perpendicularly with the hardened surface. Therefore, it does not stagnate and flows out easily, making the heating distribution uniform, and the cooling effect is also sufficient and uniform.Therefore, the quenching efficiency is good, and quenching irregularities such as stites are prevented. The excellent effect is that a high-precision product with no defects can be obtained.

As a result, a product with a small amount of strain deformation, a uniform hardness distribution, and high wear resistance and torsional strength can be obtained.

In addition, since a quenching water sprinkler is integrally installed on the outside of the quenching coil, the distribution density of the induced current is uniform, and quenching water does not stagnate, resulting in almost no quenching unevenness or quenching distortion. Therefore, the range of appropriate quenching conditions can be widened, and the quenching conditions can be easily set during quenching, resulting in improved work efficiency. There is also.

[Brief explanation of the drawing]

Figures 1 to 7 are explanatory diagrams of embodiments of this invention. Figure 1 is a sectional view of the main part of one embodiment, Figure 2 is a sectional view of a quenched water sprinkler, and Figures 3 and 4 are sectional views of a quenched water sprinkler.
Figure 5 is a current density distribution diagram, Figure 6 is a graph of workpiece position and deformation amount, and Figure 7 is a graph of workpiece position and hardness from the center. , 8 and 9 are schematic cross-sectional views of a hardening treatment apparatus based on the prior art. 1...Workpiece, 6...Hardened surface, 4', 4''...
...Quenched water sprinkler, 3...Quenched coil,
2″...Surface hardening treatment device, 7...Nozzle, θ...
...angle of inclination.

Claims (1)

[Scope of utility model registration request] A quenching water sprinkler facing the quenching surface of the workpiece is set in multiple stages in the axial direction of the workpiece, and a quenching water sprinkler on the quenching surface side and a quenching coil on the opposite side are connected, and the nozzle of the quenching water sprinkler is connected to the quenching coil on the opposite side. In the surface hardening treatment device for a workpiece, which is installed at an angle with respect to the hardening treatment surface of the workpiece, at least one nozzle provided on the surface of the quenching water sprinkler that is provided opposite to the hardening treatment surface of the workpiece is connected to the workpiece surface hardening treatment device. The nozzles of the quenching water sprinklers at each stage are formed to be inclined with respect to the quenching surface of the workpiece, and the inclinations of the nozzles of the quenching water sprinklers at each stage are distributed in opposite directions relative to the center in the longitudinal direction of the workpiece. Features: Surface hardening treatment equipment for workpieces.