JP3404778B2 - Monitoring device for lubrication device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lubricating device for supplying a lubricant to a plurality of supply points and monitoring the external leakage of the lubricant.

[0002]

BACKGROUND ART Conventionally, as a lubrication device for supplying a lubricant to a plurality of supply points, a plurality of distribution valves are provided in a pipe in which the lubricant is pumped from a pump, and a plurality of supply points are respectively supplied from the distribution valves. For example, some lubricants are supplied to bearings, but the lubricant may leak due to breakage of piping from the distribution valve to each supply point. If this leak cannot be detected, the bearing may be burned or damaged due to insufficient supply of the lubricant.

As a solution to this problem, the applicant of the present invention has proposed a monitoring device for a lubricating device as shown in FIGS. 3 and 4 (Japanese Patent Application No. 4-262935). As shown in FIG. 3, the lubricating device has a pump 10, and the lubricant pumped from the pump 10 is supplied to a supply means, for example, a progressive parent distribution valve 12. In the parent distribution valve 12, a plurality of spools contained in the valve body are sequentially operated, and a predetermined amount of lubricant determined by the spool diameter is supplied to another supply means, for example, progressive child distribution valves 14 and 16. Supplied.
Similarly to the parent distribution valve 12, the child distribution valves 14 and 16 sequentially operate the spools in the valve body to supply a predetermined amount of lubricant to the pipe 18,
Supply via 20 to a supply location, for example bearings 22, 24.

The monitoring device has a pressure sensor 2 in the vicinity of the outlets of the child distribution valves 14 and 16 in the pipes 18 and 20.
It has 6, 28. These pressure sensors 26 and 28 detect the pressure of the lubricant in the pipes 18 and 20, and these pressure detection signals are digitized by an A / D converter (not shown) and supplied to the microcomputer 30.

The microcomputer 30 stores reference pressure data for each of the pipes 18 and 20 in a built-in memory. These reference pressure data are determined based on the pressure detection signals of the pressure sensors 26 and 28 at a predetermined monitoring time Tm (second) in the normal operating state of the lubricating device. For example, as shown in FIG. 4A, the maximum value of the pressure sensors 26 and 28 at the monitoring time Tm (second) is set as the reference pressure data.

The microcomputer 30 determines each comparative pressure data based on the pressure detection signals of the pressure sensors 26 and 28 at the monitoring time Tm (second) in the normal operating state of the lubricating device. For example, FIGS. 3B and 3C
As shown in, the maximum value in the monitoring time Tm (second) is set as the comparative pressure data.

Further, the microcomputer 30 calculates the lower limit alarm pressure which is lowered by a predetermined drop rate X% from the reference pressure data. For example, as shown in FIG. 3 (c), the comparison pressure data is lower than the lower limit alarm pressure. When the value is small, an alarm is issued to notify that there is a pipe leak in the pipe 18 or 20 corresponding to this comparative pressure data, and
The fact is displayed on the CRT 32 attached to the microcomputer 30.

Further, the microcomputer 30 is shown in FIGS. 3 (a), 3 (b) and 3 (c) for each of the pressure sensors 26 and 28.
When the comparative pressure data is larger than the predetermined upper limit alarm pressure Pu as shown in FIG. 5, it is determined that the pipe provided with the pressure sensor that generated the comparative pressure data is blocked, and an alarm sound is generated. At the same time, that fact is displayed on the CRT 32.

As shown in FIG. 3 (b), when each comparative pressure data is located between the lower limit alarm pressure and the upper limit alarm pressure, the microcomputer 30 determines that each pipe 18 or 20 is normal. ,do nothing.

[0010]

However, in the case of comparing the lower limit alarm pressure based on the predetermined reference pressure data with each comparison data as described above, the reference pressure data is used as the lubricant after the start of the operation of the lubricating device. If the temperature is determined or the bearing temperature is not sufficiently increased, the value of the reference pressure data becomes higher than that when the reference pressure data is determined during normal operation. Therefore, since the lower limit alarm pressure is determined based on this reference pressure data, in this state the pipes 18, 20
Even if a leak occurs, there is a problem in that the comparative pressure data does not fall below the lower limit alarm pressure and the leak cannot be detected.

[0011]

In order to solve the above problems, the first aspect of the present invention provides a pump for pumping a lubricant and a lubricant pumped from the pump to a plurality of supply points. In a lubrication apparatus including a supply means, a pressure sensor provided between the supply means and the supply location, and during the operation time of the lubrication apparatus each time a predetermined time elapses And a comparison means for generating an output signal when the comparison value based on the output value of the pressure sensor is lower than the reference value, and the reference value is determined based on the past comparison values.

In a second aspect of the present invention, in the lubricating device as described above, a pressure sensor is provided, and the first aspect is based on the output value of the pressure sensor during a predetermined time in the reference operating state of the lubricating device. First comparison means for generating an output signal when the comparison value determined based on the output value of the pressure sensor decreases with the elapse of the predetermined time in the operating state of the lubricating device from the reference value, and the comparison Second comparing means for generating an output signal when the value is lower than the second reference value, and the second reference value is determined based on the past comparison value.

[0013]

According to the first aspect of the present invention, in the operating state of the lubricating device, the comparison value is determined based on the output value of the pressure sensor during this time each time a predetermined time has elapsed. The reference value is determined based on the comparison value determined before the determination. Then, when the comparison value becomes lower than the reference value, the comparison means generates an output signal.

According to the second aspect of the invention, in the operating state of the lubricating device, every time a predetermined time elapses, as in the case of the first aspect of the invention, a predetermined time elapses during this time. The comparison value is determined based on the output value of the pressure sensor, and the second reference value is determined based on the comparison value determined before the comparison value is determined. Then, when the comparison value becomes lower than the second reference value, the second comparison means generates an output signal. Further, the comparison value is compared with the first reference value determined based on the output value of the pressure sensor during the predetermined time in the reference operation state of the lubricating device. That is, the comparison value is the second reference value determined based on the previous comparison value,
Each is compared with the first reference value determined in the reference operation state.

[0015]

EXAMPLE The monitoring apparatus of this example is composed of pressure sensors 26 and 28 and a microcomputer 30 similarly to the monitoring apparatus shown in FIG. 3, and the pressure sensors 26 and 28 are a pump 10 and a distribution means which is a supply means. Valve 1
2, 14, 16 and the bearings 22, 24, which are the supply points, are provided in the lubricating device. Pressure sensor 26, 28
Are provided in the pipe 18 between the distribution valve 14 and the bearing 22 and in the pipe 20 between the distribution valve 16 and the bearing 24, respectively.

In this monitoring device, as shown in FIG. 1, first, the names of the bearings 22 and 24 to which the lubricant is supplied, and the pressure sensors 26 and 28 connected to these bearings 22 and 24 through pipes 18 and 20, respectively. Generated current,
For example, how much pressure 20 mA corresponds to is registered (step S2).

Next, the monitoring time Tm (second), the upper limit alarm pressure Pu (Kgf / cm ² ), the pressure drop rate X (%) and the automatic write cycle At (minute) are set (step S4).
The automatic write cycle At determines how many minutes each of the comparative pressure data generated each time the monitoring time Tm (second) elapses is stored. Based on the stored data, the bearings 22 and 24 are stored. It is used to display the pressure trend separately.

After the initial settings are completed in this way, the lubricating device is operated (step S6). After starting operation,
The output signals of the pressure sensors 26 and 28 change in a state where a plurality of peaks occur during the monitoring time Tm (seconds), that is, in a pulsating state, as shown in FIG.

The reference pressure data Pr is read in the state where the operation is started in this way, that is, in the reference operation state. The reading of the reference pressure data Pr is performed by the pressure sensors 26 and 28 generated in the section of the reference operation state shown in FIG.
The average value of the signals obtained by digitizing the pressure detection signals of is obtained, and these are calculated as the reference pressure data P of the pressure sensors 26 and 28.
It has been determined to be r (step S8). The reference pressure data Pr is stored in the microcomputer 30, and the reference pressure data Pr is stored in the pressure sensor 2.
The previous pressure data P1 of 6 and 28 are also stored in the microcomputer 30 (step S10).

In the normal operating state after the end of the reference operating state, the comparative pressure data P2 is read for each pressure sensor 26, 28 (step S12). The reading of the comparative pressure data P2 is also performed by setting the average value of the signals obtained by digitizing the pressure detection signal at the monitoring time Tm (second) in the normal operation state as the comparative pressure data P2 as shown in FIG.

It is judged whether or not the comparative pressure data P2 is smaller than the upper limit alarm pressure Pu (step S14). If the comparative pressure data P2 is larger than the upper limit alarm pressure Pu (step S14 is NO), the source of the comparative pressure data is generated. Since it is determined that the pipe 18 or 20 provided with the pressure sensor 26 or 28 is closed, an alarm sound is generated and the fact is displayed on the CRT 32 (step S16).

Comparative pressure data P rather than upper limit alarm pressure Pu
When it is determined that 2 is smaller (Yes in step S14), or following the alarm output and display in step S16, each reference pressure data Pr is multiplied by (1-X / 100) to determine the lower limit alarm pressure. Is determined and it is determined whether the comparative pressure data P2 is equal to or higher than the lower limit alarm pressure (step S18).

If this determination is yes, it can be determined that there is a leak in the pipes 18 and 20 provided with the pressure sensors 26 and 28 that generate the comparative pressure data P2. And an alarm sound is generated (step S20), and the pipe of the leak is stored in the memory of the microcomputer 30 (step S22).

If the comparative pressure data P2 is less than or equal to the lower limit alarm pressure (YES in step S18), or immediately after the memory is stored in step S22, the immediately preceding pressure data P1 is multiplied by (1-X / 100). Then, the immediately preceding lower limit alarm pressure is obtained, and it is determined whether the comparative pressure data P2 is equal to or higher than the immediately preceding lower limit alarm pressure (step S24).

If this judgment is YES, the temperatures of the lubricant and the bearing immediately after the standard operation are determined in the pipes 18 and 20 provided with the pressure sensors 26 and 28 generating the comparative pressure data P2. Since it can be determined that the leak is occurring in the state where the leak is not occurring, the fact is displayed on the CRT 32, and an alarm sound is generated (step S26), and the pipe of the leak is stored in the memory of the microcomputer 30. Yes (step S28).

When the comparative pressure data P2 is larger than the lower limit alarm pressure (YES in step S24), or after the memory is stored in step S28, the comparative pressure data P2 is stored as the immediately preceding pressure data P1 (step (S30), the first determination cycle is ended, the process returns to step S12, and the second determination cycle is started by repeating step S12 and subsequent steps. After that, the determination cycle is sequentially executed in the same manner.

In this way, since the comparative pressure data P2 is set to the immediately preceding pressure data P1 in step S30, and the steps from step S12 are repeated, for example, in the first determination cycle in the normal operation state of FIG. 2, the immediately preceding pressure data P2 is obtained. Although the reference pressure data Pr is used as the above, in the second determination cycle, the immediately preceding pressure data P2 is used.
The first comparison pressure data P1 is used for.

Therefore, in the second determination cycle, the lower limit alarm pressure Pr (1-X / 100) and the immediately preceding lower limit alarm pressure P1 (1-X / 100) are different values,
As shown in the second determination cycle, even if the second comparison pressure data P2 does not fall below the lower limit alarm pressure Pr (1-X / 100) despite the leak, the immediately preceding lower limit alarm pressure It is lower than P1 (1-X / 100), and it can be detected that a leak has occurred.

The n-th determination cycle is for the case where the pipe is closed, and the comparative pressure data P2 is equal to or higher than the upper limit alarm pressure Pu.

Although not shown in the flow chart, the pressure data stored in the memory can be saved every time the automatic writing cycle At elapses, and the saved data can be displayed on the CRT 32 or the pressure data can be displayed in a graph. It can be done.

In the above embodiment, only two bearings to which the lubricant is supplied are shown. However, the number of these bearings can be further increased, and only two child distribution valves are shown. The number of child distribution valves can also be increased.

Further, in the above embodiment, the lower limit alarm pressure P
r (1-X / 100) and immediately lower limit alarm pressure P1 (1-
X / 100), it is judged whether or not the comparative pressure data P2 is lower. In addition to this, it is lower than the drop rate X%, for example, by X / 2%, the reference pressure data Pr or the immediately preceding pressure. It may also be determined whether the comparative pressure data P2 is lower than the data P1. That is, the comparison pressure data P
A comparison of whether 2 is greater than or less than Pr (1-X / 200) and a comparison of greater than or less than P1 (1-X / 200) may be added.

Further, in the above embodiment, the comparative pressure data of the previous determination cycle is used as the immediately preceding pressure data of the next time, but the immediately preceding pressure data is not limited to the previous comparative pressure data, but the comparison pressure of the previous two times. The data may be used, or the data obtained by statistically processing the average value, the maximum value, the minimum value, or the like of the past comparative pressure data may be used.

[0034]

As described above, according to the first aspect of the present invention,
When the comparing means compares the reference value with the reference value based on the output value of the pressure sensor during the above-mentioned time every time a predetermined time in the operating state of the lubricating device elapses, and the comparison value becomes lower than the reference value. The output signal is generated, but the reference value is not a predetermined constant value but is determined based on the past comparison value, so the reference value that reflects the temperature change of the lubricant and the temperature change of the supply location such as the bearing. Has become. Therefore, it is possible to prevent the comparison value from being lower than the reference value, even though the lubricant leaks which may occur when a predetermined constant value is used as the reference value.

In the second aspect of the invention, as in the first aspect of the invention, the second comparing means outputs the output of the pressure sensor during the above-mentioned time each time a predetermined time in the operating state of the lubricating device elapses. In addition to comparing the comparison value based on the value with the second reference value determined based on the past comparison value, and generating an output signal when the comparison value becomes lower than the second reference value,
The first comparing means generates an output signal when the comparison value is lower than the first reference value based on the output value of the pressure sensor during a predetermined time in the reference operating state of the lubricating device. Therefore, for example, in the first invention alone, when the comparison value in the state of leakage is used as the reference value, it becomes impossible to monitor the occurrence of leakage thereafter, but in the second invention, Since the value is also compared with the predetermined first reference value, this can be monitored even in the state where the leakage continues.

[Brief description of drawings]

FIG. 1 is one of the monitoring devices for a lubrication device according to the present invention
It is an operation | movement flowchart of an Example.

FIG. 2 is a timing chart showing an operation state of the embodiment.

FIG. 3 is a piping system diagram of a conventional monitoring device and the above embodiment.

FIG. 4 is a diagram showing an operating state of a conventional monitoring device.

[Explanation of symbols]

10 pump 12 parent distribution valve 14 16 child distribution valve 22 24 bearing (supply point) 26 28 pressure sensor 30 microcomputer (first and second comparison means)

Claims (2)

(57) [Claims] 1. A lubrication apparatus comprising: a pump for pumping a lubricant; and a supply means for supplying the lubricant pumped from the pump to a plurality of supply points, respectively. Generates an output signal when the comparison value based on the output value of the pressure sensor during the above-mentioned time and the pressure sensor provided between and the predetermined time in the operating state of the lubrication device have decreased below the reference value A monitoring device for a lubricating device, characterized in that the reference value is determined based on a past comparison value. 2. A lubricating device comprising a pump for pumping a lubricant and a supply means for supplying the lubricant pumped from the pump to a plurality of supply points, respectively. The pressure sensor provided between the first and second reference values based on the output value of the pressure sensor during a predetermined time in the reference operating state of the lubricating device, and the predetermined time in the operating state of the lubricating device. And a first comparison means for generating an output signal when the comparison value determined based on the output value of the pressure sensor decreases each time, and an output signal when the comparison value decreases below the second reference value. And a second comparison means, wherein the second reference value is determined on the basis of the past comparison value.