JPS5833134A - Monitoring device for bearing temperature - Google Patents

Abstract

PURPOSE:To enable the previous protection of a bearing even if a pointer of a protector does not swing to a set point, by monitoring a bearing temperature based on a temperature rise gradient. CONSTITUTION:A bearing temperature detected and stored in a memory 4 through a given interval time generator 3 by a sensor 1 before it is processed by a converter 2, is stored in a memory 5, and the content of the memory 4 is renewed into a present detected temperature. A subtraction device 6 computes a temperature gradient, and if the temperature gradient exceeds a set value, an alarm is generated by an alarm unit 11 through a comparator 7. The use of a system, in which temperature is monitored based on the temperature gradient, permits the previous and reliable protection for the temperature rise of the bearing even if a pointer of a protector does not swing to a set point.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for preventing bearing seizing by ensuring reliable operation even when the bearing temperature rises rapidly.
The present invention relates to a bearing temperature monitoring device.

Conventionally, as a film preservation device for a bearing, a mercury expansion type thermometer, a thermometer using a thermocouple, a resistance temperature detector, etc. are used as a sensor, and a K IJ relay is installed.When the bearing temperature rises, this relay operates. It was common for the contacts to issue an alarm.

Conventional safety protection devices are set so that the relay operates when the temperature rises to a certain value to protect the bearing, but when the bearing suddenly starts to burn out, the scorched contacts Even if the temperature starts to rise rapidly, the temperature sensing N5 of the S
It takes time η・7D) for the heat to be transferred to
There were many cases where the bearing was already burnt out by the time the relay was activated.

This invention was made in order to eliminate the above-mentioned drawbacks of the conventional method, and instead of performing a protective operation of the bearing as a result of the temperature rising to the protection set point in the conventional method, the present invention detects the rising gradient of the temperature. An object of the present invention is to provide a bearing temperature monitoring device capable of protecting a bearing even if the pointer of the maintenance device does not swing at a set point cylinder.

Hereinafter, a detailed example of the bearing temperature monitoring device of the present invention will be explained based on the drawings. FIG. 1 is a block diagram showing the configuration of this embodiment. In FIG. 1, numeral 1 is a sensor that is a temperature sensing section, and numeral 2 is a converter that converts the temperature detected by this sensor 1 into an amount of electricity.

The (support) sword of this converter 2 is designed to send data to the memory device A4. The output of this memory A4 is the memory B5゜subtractor 6
The output of the fixed interval time generator 3 for controlling the operation timing is introduced into the memory A4, the memory B5 and the subtracter 6, respectively.

First, the storage device A4 is used to store the amount of electricity from the converter 2η, and the storage device B5 is used to re-store the amount of electricity stored in the storage device A4. The outputs of memory A4 and memory B5 are sent to a subtracter 6. Subtractor 6 calculates the amount of electricity in memory A4 and memory B5.
The output is sent to the comparator 7.

The output of the constant interval time generator 3 is introduced into the comparator 7, and the output of the crop rotation setting device 8 is also introduced through the contacts 9 and 10.

This comparator 7 compares the quantity of the operation setting device 8 and the quantity of electricity of the subtractor 6, and the output of this comparator 7 is output to the alarm generator 11. There is.

The contact 9 is a contact that is closed when the bearing is started, and the contact 10 is a contact that is closed when the bearing is operating in a steady state. The operation of the constructed bearing temperature monitoring device of the present invention will be explained. The temperature detected by the sensor 1 is converted into an electrical quantity by the converter 2, and stored in the memory A4.The stored content of the memory A4 is designated as To.

Next, the signal from the constant time generator 3 that is generated at regular intervals is Lv, and the contents of the memory A4 are transferred to the memory B5 (here, the memory content T is transferred to the memory B5). Become).

Next, 2 new converters were sent and 1! amount of electricity (T,
) is updated and stored in the memory A4 again.

Next, g! of the fixed interval time generator 3! The subtractor 6 subtracts the content of the comparator B5 from the content ρ of the memory A4. The amount of output from this subtraction profit ερ is T, -To/△
t, and if T, -70=△T, then △T/△t, which means the rising gradient of temperature.

How can I determine the amount of this upward slope by setting the operation setting device 8? Quantity and comparator? Compare with. Repeat this operation constantly. The comparator 7 compares the amount of machining installed in the operation setting device 8 with the amount of temperature rise gradient, and if the result is a match or the temperature rise gradient amount is λ,
An alarm is output from the comparator 7, and an alarm is issued from the alarm device 11≧.

Here, in order to facilitate understanding of this invention, [i.

This will be explained in further detail with reference to FIG. In FIG. 2, the horizontal axis is the time axis, and the vertical axis is the temperature axis. A portion 12 in FIG. 22 shows a state in which the temperature increases by L when the bearing is started from a state where it has been stopped for a long time and begins to operate.

Kayata. Reference numeral 13 indicates a state in which the bearing is in a steady operating state and the temperature of the bearing has settled down to one temperature. If you continue to operate in this condition, what kind of abnormality (t) will occur?

At point ), the direction ηλ from TaZ)λ to Tb is shown by the dark line.
Then the temperature begins to rise and it becomes a trap.

At this time, the sensor 1 detects the temperature rise with a delay of one hour, as shown by the dotted line. Considering this, when it is detected at 21 points, the bearing abnormality point is already considered to be Tb' (3), and at the alarm point indicated by 14, ρ ≥ L
In the case of a W protection device that is designed to operate in a similar manner, by the time the protection device issues an alarm temperature warning, the actual temperature at the abnormal point of the bearing is likely to be even higher.

Therefore, in the device of the present invention, in the region 13, the signal of the subtracter 6 in FIG. Although there is a delay time at time 1 of t,
It is possible to issue an alarm based on a change in temperature gradient, and it is possible to issue an alarm by predicting burnout. Therefore, a warning can be issued much faster than conventional devices.

In addition, the reason why the contacts 9 and 10 are divided into two parts in Fig. 1 is because the temperature gradient is different during startup and during steady operation, as shown in Fig. 2. This is because it is divided into two types: one for startup only and one for constant use.

Also, above! ! - In the example, we explained the case where the temperature rises to prevent burnout of the bearing, but it is a separate device from the bearing and the temperature is usually controlled at a constant level, so there is no η)
It can also be used as a device to prevent abnormal temperature drops due to

According to the above process, if the bearing temperature monitoring device of this invention is used,
The temperature of the bearing in normal operation is constantly monitored at fixed time intervals using the temperature rise (△T) as the differential amount (△T/Δt), and this value is adjusted to the preset value. If the differential amount matches or exceeds it, an alarm will be issued ↓, so even if the pointer of the maintenance device for one bearing does not swing at set point 1,
It is possible to protect the bearing to a certain extent.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of an example of the bearing temperature monitoring device of the present invention, and FIG. 2 is a diagram showing the relationship between time and temperature to explain the production of the bearing temperature monitoring device of the present invention. be. DESCRIPTION OF SYMBOLS 1...Sensor, 2...Converter, 3...-foot interval time generator, 4...Memory A, 5...Memory B, 6...
...Subtractor, 7...Comparator, 8...Production setting device, 9
, 10... Corrosion, 11... Alarm. Agent Shin Kuzuno −

Claims (1)

[Claims] A means for detecting the temperature of the bearing and converting it into an electrical quantity; a first memory for storing the electrical quantity converted by the means; a memory content of the first memory that is transferred and stored at each required time; A storage device for W42 that outputs W41 as a temperature increase gradient amount, a subtracter that outputs the above W41 as a temperature increase gradient amount, and a temperature increase gradient amount output from this subtractor η) and an operation set amount by the operation foot device are compared and both are calculated. It matched! ! Or a bearing temperature monitoring device comprising a comparator that activates an alarm when the temperature increase gradient amount exceeds the operating setting value Fλ.