DEVICE AND METHOD FOR MEASURING END SURFACE TURNING TEMPERATURE

Abstract

The invention provides a device and method for measuring the temperature of end face turning, which belong to the technical field of cutting and are applicable for measuring the temperature of cutting area during end surface turning. The device comprises a thermocouple sensor, a slip ring and a specially designed experiment workpiece. The circular ribs designed on the experiment workpiece transform the end surface turning into cylindrical turning. The design of a through hole and a blind hole makes the thermocouple sensor reasonably buried in the workpiece, which improves the safety of the turning process and the stability of signals. At the same time, the interference between devices is eliminated by using the slip ring structure. A temperature signal is collected by a data collection card via the slip ring and transmitted to a computer, and finally, a relatively accurate end surface turning temperature is obtained. The present invention has simple structure and easy operation, and provides a good device and method for realizing accurate measurement of end surface turning temperature.

Claims

1. A device for measuring end surface cutting temperature, wherein the device comprises a thermocouple sensor, a slip ring, a temperature signal processing end and an experiment workpiece; the experiment workpiece has a cylindrical shape, with a clamping space reserved on the left side, the space equal to the width of a turning tool reserved on the right side, and the prominent circular ribs in the middle; each circular rib has two holes, one is a blind hole, and the other is a through hole; the central axes of the blind hole and the through hole are on the same line; a probe of the thermocouple sensor is arranged in the blind hole, and the other side of the thermocouple sensor is connected with a slip ring rotor through an input wire; the slip ring rotor is located outside the right side of the experiment workpiece, which are fixed on a rotor fixing groove through screws, and the slip ring rotor is maintained coaxial with the experiment workpiece to counteract centrifugal force; a slip ring stator is connected with the temperature signal processing end through an output wire, and at the same time, the slip ring stator is fixed on a fixing bracket through a baffle plate to prevent from rotating; and the cutting edge of the turning tool is used for turning the circular ribs.

2. The device in the claim 1, wherein the number of the circular ribs on the experiment workpiece is more than two; the height of the circular ribs is from 5 to 15 mm and is gradually reduced from left to right; the thickness of the circular ribs is not greater than the width of the cutting edge; and the grooves in the circular ribs are formed by a slotting cutter and maintained a certain width.

3. The device in the claim 1, wherein the blind hole and the through hole are processed by an electrical discharge drilling machine, the diameter of the through hole which is processed by one step is larger than that of the blind hole, and then the blind hole of which the diameter is equivalent to that of the probe of the thermocouple sensor is processed via the through hole; and the holes of each circular rib are distributed at a certain angle and perpendicular to the axial plane.

4. A measurement method for measuring end surface cutting temperature, comprising the following steps: (1) Installing the device; tightening and fixing the device; and connecting a signal output wire to a data collection card; (2) Aligning the cutting edge to the rightmost circular rib; setting the cutting parameters according to the data target; collecting data via the data collection card at the same time; and feeding the turning tool according to the set cutting feed until the probe of the thermocouple sensor is cut off and cannot collect temperature data; (3) Repeating the above operations to collect the temperature data obtained on each circular rib; (4) Processing the temperature data; taking the fluctuation data in the last several cycles of each set of temperature curves; eliminating obvious interference data; obtaining the maximum temperature value measured in each set; making intercomparsion; and taking the maximum value, thus a relatively accurate end surface turning temperature is obtained.

Description

DESCRIPTION OF DRAWINGS

[0015] FIG. 1 is a structural schematic diagram of the device of the present invention.

[0016] FIG. 2 is a structural schematic diagram of the device of the present invention from the right view.

[0017] FIG. 3 is a structural schematic diagram of the device of the present invention after experiment.

DETAILED DESCRIPTION

[0018] Specific embodiment of the present invention is further described below in combination with appended drawings and the technical solution.

[0019] As shown in FIG. 1, the device comprises a thermocouple sensor 5, a slip ring 9, a temperature signal processing end 16 and an experiment workpiece 1; the experiment workpiece 1 has a cylindrical shape, with a holding space reserved on the left side, a space equal to the width of a turning tool reserved on the right side, and the prominent circular ribs 2 in the middle. The number of the circular ribs 2 on the experiment workpiece 1 is more than two; the height of the circular ribs 2 is from 5 to 15 mm and is gradually reduced from left to right; the thickness of the circular ribs 2 is not greater than the width of the cutting edge 10, so that cylindrical turning process can be made equivalent to 90 end surface turning; and the grooves in the circular ribs 2 are formed by a slotting cutter and maintained a certain width. Each circular rib 2 has two holes, one is a blind hole 3, and the other is a through hole 4; the central axes of the blind hole 3 and the through hole 4 are on the same line. The blind hole 3 and the through hole 4 are processed by an electrical discharge drilling machine, the diameter of the through hole 4 which is processed by one step is larger than that of the blind hole 3, and then the blind hole 3 of which the diameter is equivalent to that of the probe of the thermocouple sensor 5 is processed via the through hole 4; this is mostly done to prevent the discharge interference of upper-layer through hole 4 when the blind hole 3 is processed. The holes of each circular rib (2) are distributed at a certain angle and perpendicular to the axial plane, which is convenient to install a thermocouple probe and balance the centrifugal force. A probe of the thermocouple sensor 5 is arranged in the blind hole 3, and the other side of the thermocouple sensor 5 is connected with a slip ring rotor 8 through an input wire 6; the slip ring rotor 8 is located outside the right side of the experiment workpiece 1, the they are fixed on a rotor fixing groove 12 through screws 7, and the slip ring rotor 8 is maintained coaxial with the experiment workpiece 1 to counteract the centrifugal force; a slip ring stator 9 is connected with the temperature signal processing end 16 through an output wire 15, and at the same time, the slip ring stator 9 is fixed on a fixing bracket 13 through a baffle plate 14 and prevented from rotating; and the cutting edge 10 of the turning tool 11 is used to cutting the circular ribs 2. The temperature signal processing end 16 is a processing end with relatively high collection frequency, and preferably a synchronous signal collection card.

[0020] The device is installed on a machine tool, and the left end of the device is clamped by a three jaw chuck. The machine tool is started at a speed; the circular ribs 2 are turned by the cutting edge 10 with a corresponding feed; the collected temperature signal is changed along with the change of the distance between the turning tool and the probe of the thermocouple sensor 5; the temperature signal presents a wave shape after being processed by the temperature signal processing end 16; as the cutting amount of the circular ribs is increased, when the distance to the probe gets small, the peaks rise in turn; when the cutting edge 10 cuts through the probe, the data measured at this moment is the closest to the real turning temperature.

[0021] Further, the probe of the thermocouple sensor 5 is damaged and does not accept temperature data any more. However, because of the existence of data collection frequency, the distances from the positions of the last data collection to the probe are different, so that the final signal values are different, and therefore it is necessary to perform analysis according to the data obtained from multiple circular ribs 2. The structure of the device after the turning process is as shown in FIG. 3.

[0022] Further, the several sets of data obtained are imported and sorted at a terminal, and the data is smoothed and fitted. In experiment, the fluctuation data in the last several cycles of each set of temperature curves is taken; obvious interference data is eliminated; the maximum temperature value measured in each set is obtained; intercomparsion is made; and the maximum value is taken, thus a relatively accurate end surface turning temperature is obtained.