JPS6032107Y2 - Direct current induction hardening equipment - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a direct current induction hardening device.

Direct energization type induction hardening equipment is a device that conducts surface hardening by applying high frequency current directly to the metal member to be hardened, heating only the surface of the metal member, and then cooling it. Generally, It includes two contact elements configured to make substantially surface contact with the metal member to be hardened, and a high frequency current is applied between the contact elements while the contact elements and the metal member are pressed against each other. is now energized.

Therefore, in such a direct current induction type induction hardening device, current must be applied while the contact element and the metal member are in surface contact with each other.

However, in conventional direct current induction hardening equipment, each contact element is rigidly fixed with bolts or the like to a lead terminal member or support member connected to the high frequency current generator, and therefore the contact element It is difficult to appropriately adjust the position of the contact element relative to the metal member so that the contact surface of the element is in proper surface contact with the surface of the metal member to be hardened.

Therefore, if the metal parts are not supported properly,
When a contact element and a metal member make point contact and are pressed together, one or both of the contact element or the metal member may be damaged or deformed.

Furthermore, if current is applied between the contact elements in such a state where the contact is insufficient, sparks will occur between the contact element and the metal member, and as a result, not only will proper surface hardening and quenching not be carried out, but the contact Significant damage may occur to one or both of the elements or metal parts.

In view of the above-mentioned problems with conventional direct current induction hardening equipment, the present invention has developed a direct current induction hardening equipment that is configured so that the contact element can make proper surface contact with the metal member to be hardened. is intended to provide.

According to the present invention, this object has a contact surface at its tip that makes substantially surface contact with the surface of the article to be hardened, and is configured to directly apply a high frequency current to the article.
and a second contact element, first and second contact element support means for pivotally supporting the first and second contact elements at their root portions, and the first and second contact elements, respectively. This is achieved by a direct current induction type induction hardening apparatus characterized in that it includes current supply means for passing a high frequency current between the contact elements of the article through the article.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail with reference to preferred embodiments thereof, with reference to the accompanying drawings.

FIG. 1 is a partially cutaway view of one embodiment in which the direct energization type induction hardening device of the present invention is applied to surface hardening and hardening of rack teeth of a rack bar shaft used in an automobile steering device. Figure 2 is the line in Figure 1■
-■ is a horizontal cross-sectional view.

In these figures, reference numeral 1 denotes a first contact made of a substantially plate-shaped body, and a contact configured to make surface contact with the rack tooth 3 of the rack bar shaft 2 to be surface hardened and quenched at one end thereof. It has a surface 4.

The other end of the contact 1 has a substantially semicircular upper end surface 5 and is received in a contact receiver 7 provided with a semicircular recess 6 having a curvature substantially equal to the curvature of the upper end surface. ing.

Further, the contact 1 has a substantially semicircular projection 8 at the upper end of one side, and this projection 8 is a substantially semicircular projection 8 provided on the contact receiver 7 to prevent the contact 1 from falling off. It fits into the recess 9 which has a semi-circular arc shape.

Furthermore, a contact support 10 is arranged on the other side of the contact 1.

A very small gap is provided between the retaining parts of the contact 1, the contact receiver 7, and the contact support 10, so that the contact 1 can be attached to the contact receiver 7 and the contact support 10. In between, it can pivot 1 about the axis 11 of the semicircular recess 9.

The contact support 10 is removably fixed to the contact receiver 7 by bolts 12.

The contact receiver 7 is fixedly attached to a wedge-shaped recess 14 formed at one end of the support bar 13 via an insulator 15.

A second contact 16 similar to the first contact 1 is supported at the other end of the support bar 13 .

In this case, the second contact 16 is received directly in a semicircular recess 6' formed in the support bar 13.

The contactor 16 has a contactor support 10' having a structure similar to that of the contactor support 10 arranged on one side thereof,
Further, by fitting the semicircular arc-shaped protrusion 8' formed on one side of the support bar 13 into the semicircular arc-shaped recess 9' formed in the support bar 13, the axis line 17 of the recess 9' is prevented from falling off. It is designed to be able to pivot around.

These first and second contacts 1 and 16 are reciprocated by a cylinder-piston device (not shown), respectively, and are fixed to press the contact supports 10 and 10' against the respective contacts. Devices 18 and 18' allow for fixation in any pivot position.

Further, the contact receiver 7 and the support bar 13 are connected to a high frequency current generator 21 by lead wires 19 and 20, respectively.
and 16 can be supplied with high frequency current.

The rack bar shaft 2 to be surface hardened and hardened is driven by rack teeth 3 at both ends thereof by rack bar shaft drive devices 22 and 23, which are driven up and down in synchronization with each other by cylinder piston devices (not shown).
The first contactor 1 and the second contactor 16 are brought into contact with each other at the tooth groove portions of the contactor.

In operation, first the rack bar shaft 2
After being raised by the shaft drives 22 and 23 and pivoting the contacts 1 and 16 so that their contact surfaces are in proper surface contact with the surfaces of the tooth grooves of the rack teeth 3, the contact fixing devices 18 and 18
' are pressed against the contact supports 10 and 10', respectively, and the contacts are fixed in a predetermined pivot position.

Next, by operating the switch of the high frequency current generator 21, a high frequency current is passed between the first contact 1 and the second contact 16 via the rack bar shaft 2.

(Each rack tooth of the rack bar shaft is heated by a high frequency current, and then coolant is sprayed from a coolant spray nozzle (not shown in the figure) to appropriately harden and harden the surface.

In this case, as shown in FIG. 3, even if the rack bar shaft 2 to be surface hardened is not accurately supported in its predetermined state, the rack bar shaft is driven relative to the contact. When pressed by devices 22 and 23, contacts 1 and 16 move along their axes 11 and 17.
, thereby ensuring that their contact surfaces are in proper surface contact with the tooth spaces of the rack bar shaft.

Thus, with the direct current induction hardening device of the present invention, when the contact and the metal member to be surface hardened are pressed against each other, damage or deformation to either member can be avoided.

In addition, since the high-frequency current is applied while the contact surface of the contact and the contact surface of the metal member to be hardened are in proper surface contact, there is no spark between the contact and the metal member to be hardened. This prevents significant damage to one or both of the contacts or metal components due to
This not only makes it possible to increase the life of the contact, but also enables uniform heating of the metal member to be hardened, thereby improving the hardening quality.

In the above, one embodiment in which the direct current induction hardening device according to the present invention is applied to surface hardening of rack bar shafts has been described in detail. It will be appreciated that it is also applicable to case hardening of other similar metal parts other than shafts.

Also, in the illustrated embodiment, the contacts are configured to be pivotable about their axes, but the contacts may be adapted to suitably adjust their contact surfaces in any direction, e.g. with a ball-socket. It will be appreciated that it may be configured to be supported by other suitable pivoting means, such as.

[Brief explanation of drawings]

Fig. 1 is a partially cutaway view of one embodiment in which the direct energization type induction hardening device of the present invention is applied to surface hardening and hardening of the rack teeth of a rack bar shaft used in an automobile steering device. , Fig. 2 is a vertical cross-sectional view along the line ■-■ in Fig. 1, and Fig. 3 shows the operation of the direct current type induction hardening device according to the present invention when the rack bar shaft is not supported properly. This is the same space as in Figure 2. 1...First contactor, 2...Rack bar shaft, 3...Rack teeth, 4...
Contact surface, 5... Upper end surface, 6, 6'...
Recess, 7...Contact receiver, 8.8'...
・Protrusion, 9,9′・・・Recess, 10・・・・
...Contact support, 11... Axis, 12...
...Bolt, 13...Support bar, 14...
...Wedge-shaped recess, 15...Insulator, 16...
...Second contactor, 17...Axis, 18,
18'... Contact fixing device, 19, 20...
... Lead wire, 21 ... High frequency current generator, 22.23 ... Rack bar shaft drive device.

Claims (1)

[Scope of utility model registration request] first and second contact elements having contact surfaces at their tips that make substantially surface contact with the surface of the article to be hardened and configured to be able to directly apply a high frequency current to the article; and first and second contact element support means for pivotally supporting a second contact element at their root portions, respectively; 1. A direct current induction type induction hardening device, comprising a current supply means for supplying current.