JPS6157144B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a processing device having a temperature control function, and its purpose is to make the temperature of the shaft head lubricating oil follow the temperature change of the cutting fluid that influences the temperature of the workpiece. The objective is to prevent positional errors in the center of the machined hole from occurring due to differences in thermal expansion.

Generally, when machining is performed using cutting fluid, the temperature of the workpiece is approximately the same as the temperature of the cutting fluid.
When this cutting fluid has a large volume, the temperature of the cutting fluid changes extremely slowly with respect to changes in room temperature.

For this reason, with conventional temperature control devices that allow shaft head lubricating oil to follow changes in room temperature, the temperature difference between the workpiece and the shaft head changes, causing a position error in the center of the machined hole due to thermal expansion. There was a problem.

As shown in FIG.
When machining, the machined hole pitch of the workpiece will match the spindle pitch of the shaft head, but due to thermal expansion between the machined hole pitches of the workpiece and the spindle pitch of the shaft head at the time of machining. If the thermal expansions are not equal, considerable dimensional errors will occur in the machined hole pitch at room temperature.

In addition, if the bottom surface of the workpiece is the mounting reference surface, the thermal expansion to the center of each machined hole relative to the mounting reference surface at the time of machining is equal to the thermal expansion to the spindle center relative to the top surface of the slide table. Otherwise, a dimensional error will occur between the workpiece mounting reference plane and the center of the machined hole at room temperature.

In order to correct this dimensional error, it is necessary to process the workpiece and the shaft head with the same amount of thermal expansion.
For this reason as well, it is important to make the temperature of the lubricating oil at the shaft head follow the temperature of the cutting fluid.

Embodiments of the present invention will be described below with reference to FIG. 10 is a processing device, 11 is a bed, 12 is a feed unit installed on the bed 11, 13 is a guide surface formed on this feed unit 12, and 14 is a slide slidably guided along the guide surface 13. moving table,
15 is a shaft head installed on the sliding table 14; 16;
17 is a spindle rotatably supported on the shaft head 15; 18 and 19 are spindles 16 and 1;
7 is a processing tool inserted, 20 is a gear box installed behind the shaft head 15 and rotationally connected to each spindle 16, 17, 21 is a drive motor connected to the input shaft of the gear box 20, 22 is a A jig main body is installed on the bed 11 facing the shaft head 15, 23 is a reference surface for positioning the workpiece, 24 is a clamping device for clamping the workpiece, 25 is a storage tank for cutting fluid, 26 is a cutting fluid supply pump, 27 is pump 2
6 is connected via a conduit 28 to a cutting fluid spouting nozzle provided on the jig body 22; 29 is a return pipe for recovering the cutting fluid supplied to the workpiece; 30 is a cutting fluid that is refluxed through the return pipe 29; A temperature sensor for detecting the liquid temperature; 31 is a storage tank for lubricating oil to be supplied to the shaft head 15; 32 is a lubricating oil supply pump; 33 is connected to the supply pump 32 at one end, and the other end is connected to the shaft head 15; 34 is a return pipe that returns the lubricating oil discharged from the shaft head 15 to the storage tank 31, 35 is a heater that heats the lubricating oil, 36 is a cooler that cools the lubricating oil, and 37 is a heating 38 is a temperature detector that detects the temperature of the lubricating oil returned to the storage tank 31 from the return pipe 34. The control circuit 36 is cut as shown in FIG. Temperature detector 30 for liquid and temperature detector 3 for lubricating oil
Arithmetic circuit 40 that calculates the difference Δt from the detected temperature of No. 8.
and a comparison circuit 42 that compares the calculated value of this calculation circuit 40 and the set value to set in the setting circuit 41.
and a switch circuit 43 that turns on and off the power to the heater 35 and cooler 36 in accordance with the control signal output from the comparison circuit 42. When the calculated value Δt compared in the comparison circuit 42 is smaller than the set value to, that is, when the temperature difference between the lubricating oil temperature and the cutting fluid temperature is lower than the set value, the heater 3
5 turns on and heats the lubricating oil. Also, the calculated value △t
When is larger than the set value to, that is, when the temperature difference between the cutting fluid temperature and the lubricating oil temperature is higher than the set value, the cooler 36 is powered on to cool the lubricating oil. If the calculated value Δt matches the set value to, it means that the temperature difference between the lubricating oil temperature and the cutting oil temperature has reached the set value, and both the heater 35 and the cooler 36 are stopped. The temperature of the cutting fluid gradually changes due to room temperature changes and heat generated during machining, and the temperature of the workpiece to which the cutting fluid is supplied also changes along with the temperature of the cutting fluid. The temperature of the lubricating oil is adjusted to follow changes in the temperature of the cutting fluid, and a nearly constant temperature difference is maintained throughout the day. Therefore, the difference in relative thermal expansion between the workpiece and the shaft head is reduced and machining accuracy is improved.

Note that it is possible to deal with cases where the linear expansion coefficients of the workpiece and the shaft head are the same and cases where they are different by changing the setting value of the temperature difference set in the setting circuit 41. For example, if the coefficient of linear expansion of the workpiece and the coefficient of linear expansion of the shaft head are the same, the set value can be reduced or set to zero, and if the coefficient of linear expansion of the workpiece is large, the difference in set temperature can be increased. By making the shaft head temperature higher than the workpiece temperature, it is possible to make the amount of thermal expansion of the workpiece and the shaft head approximately equal, thereby preventing the occurrence of machining errors.

According to the present invention, the temperature of the lubricating oil circulated within the shaft head follows the temperature change of the cutting fluid supplied to the workpiece during machining, so the temperature difference between the shaft head and the workpiece is reduced. always kept constant. For this reason, the difference in thermal expansion between the two does not change over time, which eliminates errors between machined hole pitches as well as dimensional errors between the workpiece mounting reference surface and the center of the machined hole, improving machining accuracy. Contribute to

Additionally, the temperature of the lubricating oil that is circulated within the shaft head is much smaller than that of the cutting fluid, so controlling the temperature of a small volume of lubricating oil consumes less energy. It has advantages such as easy temperature control.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; Fig. 1 is an explanatory diagram showing the relationship between the workpiece and the shaft head, Fig. 2 is a diagram showing the overall configuration of the processing device, and Fig. 3 is a block diagram of the control circuit. It is a line diagram. 10...Processing equipment, 11...Bed, 12...
Feed unit, 14...Sliding table, 15...Shaft head, 16, 17...Spindle, 18, 19...
Processing tool, 22... jig body, 23... reference surface,
24... Clamp device, 25... Cutting fluid reservoir,
27... Cutting fluid ejection nozzle, 30... Temperature detector, 31... Lubricating oil reservoir, 35... Heater, 3
6...Cooler, 37...Control circuit, 38...Temperature detector, W...Workpiece.

Claims (1)

[Claims] 1 In a processing device that processes a hole in a workpiece fixed to a jig body using a processing tool installed on a rotating spindle while supplying cutting fluid, a circulation device that circulates lubricating oil within the shaft head of the processing device. a temperature adjusting device that adjusts the lubricating oil temperature by heating or cooling the lubricating oil; and a temperature adjusting means that detects the temperature of the lubricating oil and the temperature of the cutting fluid and maintains the temperature difference between the two at a constant value. A machining device having a temperature control function, comprising: a control means for causing the temperature of the lubricating oil to follow changes in the temperature of the cutting fluid.