JPH0413812A - Method and apparatus for quenching and tempering ball screw with high frequency shifting - Google Patents

Abstract

PURPOSE:To keep heating the temp. of a ball screw to the desired value and to prevent over-heating of the ball screw by adjusting heating electric power in the case of quenching and tempering. CONSTITUTION:The ball screw 1 forming ridges of (p)mm pitch is shifted to the longitudinal direction M thereof at Vmm/sec relative velocity with a heating coil 5 for high frequency quenching, an injection jacket 6 for rapidly cooling liquid and coil 11 for high frequency tempering set to the M direction, in order. At the same time, while rotating the ball screw 1 at N turns/sec rotating velocity as centering axis of the M direction, the quenching and the tempering are executed. In this method, V and N are selected so that the relation of (p/V)N=k (k is integer.) is satisfied. Further, temp. of each surface of the ball screw 1 heated with the coils 5, 11 is measured with infrared thermometers 10, 14 at each p/Vsec and according to this result, the heating electric powers with the coils 5, 11 are adjusted. By this method, the heating temps. for quenching and tempering of the ball screw 1 can be kept to the desired value.

Description

DETAILED DESCRIPTION OF THE INVENTION <Field of Industrial Application> The present invention relates to a method and apparatus for high-frequency transfer quenching and tempering of a ball screw.

<Conventional technology> Conventionally, when performing induction hardening and tempering on a ball screw, the movement quenching and tempering is performed while a preset constant power is applied to the induction hardening heating coil and the induction tempering coil. There is.

<Problems to be Solved by the Invention> Therefore, the induced power of the ball screw increases due to fluctuations in the input voltage of the high frequency moving quenching and tempering device, and the ball screw may be overheated during quenching and tempering.

The present invention has been devised in view of the above circumstances, and is a ball screw that can maintain the temperature of the ball screw at a desired value without overheating the ball screw during induction hardening or heating for tempering of the ball screw. The object of the present invention is to provide a method and apparatus for high frequency transfer quenching and tempering.

<Means for Solving the Problems> In order to solve the above problems, the high frequency moving quenching and tempering method of the present invention includes a ball screw in which threads with a pitch of pn++n are formed and sequentially arranged in the longitudinal direction of this ball screw. The ball screw or the heating coil for induction hardening, the quenching liquid injection jacket, and the induction tempering coil should be connected so that the relative velocity of the heating coil for induction hardening, the quenching liquid injection jacket, and the induction tempering coil is V mm 7 seconds. While moving the ball screw in the longitudinal direction, the ball screw is heated for hardening by an induction hardening heating coil while rotating the ball screw around an axis in the above direction at a rotational speed of N rotations for 7 seconds, and then a quenching liquid injection jacket is applied to the ball screw. In the method for high-frequency movement quenching and tempering of a ball screw, the pitch is characterized in that the ball screw is hardened by injecting a quenching liquid, and then the ball screw is heated for tempering by an high-frequency tempering coil to temper the ball screw. Between relative speed and rotational speed, (p/V)N=K (where K
is an integer), and select the above-mentioned Adjust the power of the required high-frequency heating to maintain the heating temperature for hardening the ball screw at the desired value, and also adjust the temperature of the surface of the ball screw subjected to high-frequency heating for tempering according to the results of measuring every p/V seconds. The electric power of the high-frequency heating for tempering is adjusted to maintain the heating temperature for tempering the ball screw at a desired value.

In addition, in order to solve the above problem, the high frequency moving quenching and tempering apparatus of the present invention provides a ball screw having threads with a pitch of pmm and rotating at a rotational speed of N rotations for 7 seconds with the longitudinal direction as an axis. A saddle-shaped semi-open heating coil for induction hardening and a quenching liquid injection jacket are arranged sequentially in the direction.
It comprises an induction tempering coil and a cooling liquid injection jacket, and is installed toward the ball screw between the induction hardening heating coil and the quenching liquid injection jacket and between the induction tempering coil and the cooling liquid injection jacket, respectively. comprising first and second non-contact directional temperature measuring devices, and a ball screw and an induction hardening heating coil;
A ball screw or heating coil for induction hardening, such that the relative velocity with the quenching liquid injection jacket, the induction tempering coil and the cooling liquid injection jacket is V mm 7 seconds.
, the cold liquid injection jacket, the induction tempering coil and the cooling liquid injection jacket are moved in the longitudinal direction of the ball screw, and between the pitch, relative speed and rotational speed, (p/V)N=K (where K is an integer), and the temperature of the ball screw heated for hardening by the induction hardening heating coil is measured every p/V seconds. Adjust the applied power to maintain the heating temperature for hardening the ball screw at a desired value, and apply power to the induction tempering coil in accordance with the result of measuring the temperature of the ball screw heated for tempering by the induction tempering coil. The electric power is adjusted to maintain the heating temperature for tempering the ball screw at a desired value.

<Function> A ball screw formed with threads with a pitch of pm, or a heating coil for induction hardening, a quenching liquid injection jacket, an induction tempering coil, and a cooling liquid injection jacket are moved in the longitudinal direction of the ball screw at a speed of V mm for 7 seconds. While moving the ball screw, the ball screw is rotated around the axis in the above direction at a rotational speed of N rotations for 7 seconds, and the ball screw is heated by an induction hardening heating coil, and then a cold liquid is injected from the jacket to cool the ball screw. , the ball screw is heated and tempered by an induction tempering coil, and then coolant is injected to perform aftercooling.

At this time, between the pitch of the threads formed on the ball screw, the moving speed and the rotating speed of the ball screw, as described above, the moving speed and the rotating speed are set so that the relationship of (p/V)N= is established. A first non-contact directional temperature measuring device installed toward the surface of the ball screw between the induction hardening heating coil and the quenching liquid injection jacket measures the hardening temperature every p/V seconds. Electric power is applied to the heating coil for induction hardening according to the temperature measurement results at points on the surface of the heated ball screw that are on a straight line parallel to the longitudinal direction of the ball screw and have an interval equal to the thread pitch of the ball screw. The heating temperature for hardening the ball screw is maintained at a desired value by adjusting the temperature. Similarly, the surface of the ball screw is heated for tempering every p/V seconds by a second non-contact directional temperature measuring device placed towards the surface of the ball screw between the induction tempering coil and the coolant injection jacket. Tempering the ball screw by adjusting the power applied to the high-frequency tempering coil according to the temperature measurement results at points located on a straight line parallel to the longitudinal direction of the ball screw and having an interval equal to the thread pitch of the ball screw. The heating temperature is kept at the desired value.

<Example> Hereinafter, an example of the present invention will be described with reference to the drawings. 1 and 2 are drawings for explaining a high-frequency movable hardening arm restoring device capable of realizing the high-frequency movable hardening arm restoring method for a ball screw according to the present invention, and FIG. 1 includes a ball screw. A schematic configuration diagram, FIG. 2 is an explanatory diagram of a ball screw and an infrared thermometer.

The high-frequency movable hardening arm restoring device of this embodiment is a device for hardening, hardening and after-cooling a ball screw 1, and as shown in FIG. Then, the quenching liquid injection jacket 6, the air nozzle 8, the induction tempering coil 11, the cooling liquid injection jacket 12, and the It is equipped with a contact-type directional infrared thermometer 10.14.

Elephant, the cold liquid injection jacket 6 sprays quenching liquid onto the heated ball screw 1 for quenching! , and the air nozzle 8 is a jacket that sprays the quenching liquid I attached to the surface 3 of the ball screw 1.
! , I is a nozzle that injects compressed air k that blows out. The cooling liquid jetting jacket 12 injects the cooling liquid 1 in order to cool the surface 3 of the ball screw 1 heated for tempering to room temperature.
It is a jacket that sprays 2.

The infrared thermometer 10 is installed facing the surface 3 of the ball screw l so as to be able to detect the temperature of the area between the induction hardening heating coil 5 and the quenching liquid injection jacket 6. Further, the infrared thermometer 14 is installed facing the surface 3 of the ball screw 1 so as to be able to detect the temperature of the area between the induction tempering coil 11 and the coolant injection jacket 12.

Note that the ball screw 1 is inserted in the longitudinal direction of the ball screw 1 (arrow M
a workpiece moving device (not shown) that moves the ball screw 1 at a speed of V mm 7 seconds in the direction of , and a work rotation device that rotates the ball screw 1 at a rotational speed of N rotations/second in the direction of arrow R around the longitudinal axis of the ball screw 1. A device (not shown) is provided.

A surface 3 of the ball screw 1 is formed with a spiral groove 2 having a substantially semicircular cross section and serving as a transfer surface for balls (not shown). By forming the groove 2, a screw thread 4, which is also spiral in shape and has a pitch of pm, is formed. Points A, 'B, C on thread 4 of ball screw 1
, D are on a straight line parallel to the longitudinal direction of the ball screw 1, and the interval between these points is equal to the pitch of the ball screw 1. In this embodiment, the point is selected as the center point of the width of the thread 4. Points A and B in Figures 1 and 2
, C, and D are shown, but there are similar points following the dots.

The induction hardening heating coil 5 and the induction tempering coil 11 are connected to high frequency power supplies 100 and 200 via lead wires 101 and 201, respectively. Also,
Infrared thermometers 10 and 14 are connected to high frequency power supplies 100 and 200 by signal lines 102 and 202, respectively, and output signals of infrared thermometers 10 and 14 are connected to high frequency power supplies 100 and 200 via signal lines 102 and 202, respectively. communicated.

9 is infrared rays emitted by the surface of the ball screw 1 heated by the induction hardening heating coil 5, and 13 is infrared rays radiated by the surface of the ball screw 1 heated by the induction tempering coil 11.

Next, the quenching and tempering and aftercooling operations of the ball screw 1 will be explained.

Moving speed V of ball screw 1 in the longitudinal direction of ball screw l
mm 7 seconds and rotated at a rotational speed of N revolutions/second about the longitudinal axis. In this state, a high frequency current is applied to the induction hardening heating coil 5 and the induction tempering coil 11 from the high frequency power sources 100 and 200, respectively, and from the quenching liquid injection jacket 6, the cooling liquid injection jacket 12 and the air nozzle 8, respectively. The cold liquid 28, the coolant 12, and the compressed air K are injected.

Then, the surface 3 of the ball screw 1 is heated by the induction hardening heating coil 5 and then heated by the quenching liquid I! , 1 and then adhered to the surface 3 by compressed air k! , 1 are blown away to dry the surface 3, and then the surface 3 is heated and tempered by the induction tempering coil 11, and then the cooling liquid I! , 2.

The temperature of the ball screw 1 is measured by infrared temperature change needles 10 and 14 after heating the ball screw 1 for quenching and after heating it for tempering, respectively. Using an infrared thermometer 10,
The above-mentioned point A on the heated surface for hardening of the ball screw 1,
By sequentially measuring the temperatures of B, C, D..., the temperature of the ball screw heated for quenching can be measured. That is, after measuring the temperature at a point with the infrared thermometer 10, when point B comes to the position where point B was, the temperature at point B is measured, and the temperature at point C, point D, etc. is similarly measured. measure.

However, the points after point B are point A where the temperature was measured.
In order to pass the position where , that is, to pass the aiming point of the infrared thermometer IO, 2, Jf −)
, t, shi1 (7) Hitachi pm+n, movement speed Vm
The following relationship needs to hold between m/sec and rotational speed N rotations/sec.

(p/V)N=K (1) However, K is an integer. Then, the moving speed of the ball screw 1 is V mm7
If the seconds and rotational speed N rotations/second are selected to satisfy equation (1), the points B, C1, D...
・sequentially come to the aiming point of the infrared thermometer 10, so this p
The infrared thermometer 10 detects points B, C1 and D every /V seconds.
It is possible to measure the temperature of...

The measured temperature signals at these points are sent to the lead wire 102.
is transmitted to the high frequency power source 100 through the high frequency power source 100.
The output voltage is adjusted according to the measured temperature value, and the magnitude of the high frequency current applied to the induction hardening heating coil 5 is adjusted, and the hardening heating temperature of the ball screw 1 is maintained at an appropriate value. It will be done.

Similarly, the high-frequency current is applied to the high-frequency tempering coil 11 based on the results of measuring the temperatures of points A'', B'', C'', D'', etc. heated for tempering using the infrared thermometer 14. is adjusted, and the tempering temperature of the ball screw 1 is maintained at an appropriate value.

In this example, point A1 point A'', point B, point B'', point C
1 point C11 point 5 point "..." was the center point of the thread width of the thread of the ball screw, but it is not limited to this, and these points may be placed in the groove 2, for example,
The point is that these points should be on a straight line parallel to the longitudinal direction of the ball screw 1 and spaced at intervals equal to the pitch of the threads of the ball screw 1.

In this embodiment, the case where the ball screw 1 is moved in the longitudinal direction of the ball screw 1 has been described. It may also be moved in the longitudinal direction.

<Effects of the Invention> As explained above, the method and apparatus for induction hardening of a ball screw of the present invention include a ball screw having threads formed with a pitch of p mm and induction hardening arranged sequentially in the longitudinal direction of the ball screw. The heating coil for induction hardening, the quenching liquid jetting jacket and the induction tempering coil are installed in the longitudinal direction of the ball screw or the induction hardening heating coil, the quenching liquid jetting jacket and the induction tempering coil so that the relative velocity with the heating coil, quenching liquid jetting jacket and induction tempering coil is V mm 7 seconds. At the same time, while rotating the ball screw around the axis in the above direction at a rotational speed of N rotations for 7 seconds, the ball screw is heated for hardening by an induction hardening heating coil, and then the quenching liquid is injected from the quenching liquid injection jacket. In a method for high frequency movement quenching and tempering of a ball screw, the pitch, relative speed and rotation are During the speed, (p/V)N=K (where K
is an integer), and the temperature of the surface of the ball screw subjected to high frequency heating for hardening is measured every p/V seconds. Adjust the power of the required high-frequency heating to maintain the heating temperature for hardening the ball screw at the desired value, and also adjust the temperature of the surface of the ball screw subjected to high-frequency heating for tempering according to the results of measuring every p/V seconds. The electric power of the high-frequency heating for tempering is adjusted to maintain the heating temperature for tempering the ball screw at a desired value.

Therefore, according to the method and apparatus for high-frequency transfer quenching and tempering of a ball screw of the present invention, the ball screw is not overheated when the ball screw is heated for induction hardening and when the ball screw is heated for tempering. The heating temperature of the ball screw can be maintained at a desired value.

[Brief explanation of drawings]

FIGS. 1 and 2 are drawings for explaining a high-frequency moving quenching and tempering device that can implement the high-frequency moving quenching and tempering method for a ball screw according to the present invention, and FIG. 1 includes a ball screw. A schematic configuration diagram, FIG. 2 is an explanatory diagram of a ball screw and an infrared thermometer. 1...Ball screw, 4...Screw thread, 5...
Heating coil for induction hardening, 6... Elephant, cold liquid injection jacket, 10.14... Infrared thermometer, 11... Induction tempering coil, 100.200... High frequency power supply. Patent applicant: Fuji Electronics Co., Ltd. Agent: Takaharu Ohnishi, patent attorney

Claims (2)

[Claims] (1) The relative speed between a ball screw with threads with a pitch of pmm and the induction hardening heating coil, quenching liquid injection jacket, and induction tempering coil arranged sequentially in the longitudinal direction of this ball screw is Vmm/sec. As is,
While moving the ball screw or the heating coil for induction hardening, the quenching liquid injection jacket, and the induction tempering coil in the longitudinal direction of the ball screw, and rotating the ball screw around the axis in the above direction at a rotational speed of N rotations/second,
After heating the ball screw for hardening using an induction hardening heating coil, quenching is performed by injecting a quenching liquid from a quenching liquid injection jacket, and then the ball screw is heated for tempering using an induction tempering coil. In the high-frequency movement quenching and tempering method for a ball screw characterized by tempering, there is a relationship between the pitch, relative speed and rotational speed of (p/V)N=K (where K is an integer). The above-mentioned V and N are selected so that the temperature of the surface of the ball screw subjected to high-frequency heating for hardening is p/V.
The power of the high-frequency heating for hardening is adjusted according to the results measured every second to maintain the heating temperature for hardening the ball screw at a desired value, and the temperature of the surface of the ball screw subjected to high-frequency heating for tempering is adjusted. High frequency moving quenching and tempering of a ball screw, characterized in that the heating temperature for tempering the ball screw is maintained at a desired value by adjusting the electric power of the high frequency heating for tempering according to the results measured every p/V seconds. Method. (2) A saddle-shaped semi-open heating coil for induction hardening arranged sequentially in the direction of a ball screw formed with threads with a pitch of pmm and rotating at a rotational speed of N revolutions/second with the longitudinal direction as an axis. , comprising a quenching liquid injection jacket, an induction tempering coil, and a cooling liquid injection jacket, and between the induction hardening heating coil and the quenching liquid injection jacket and between the induction tempering coil and the cooling liquid injection jacket. first and second non-contact directional temperature measuring devices respectively installed toward the ball screw, and
The ball screw or the heating coil for induction hardening, the quenching liquid jetting jacket, such that the relative speed between the ball screw and the heating coil for induction hardening, the quenching liquid jetting jacket, the induction tempering coil and the cooling liquid jetting jacket is Vmm/sec. While moving the induction tempering coil and the coolant injection jacket in the longitudinal direction of the ball screw, between the pitch, relative speed and rotational speed, (p/V)N=K
(However, K is an integer) The electric power applied to the heating coil is adjusted to maintain the heating temperature for hardening the ball screw at a desired value, and the induction tempering coil is heated according to the result of measuring the temperature of the ball screw heated for tempering by the induction tempering coil. An apparatus for high-frequency moving quenching and tempering of a ball screw, characterized in that the heating temperature for tempering the ball screw is maintained at a desired value by adjusting the electric power applied to the ball screw.