JP2022187075A - Grease supply method and grease supply system - Google Patents

Abstract

To provide a grease supply method which enables improvement of durability of a slide bearing, and to provide a grease supply system.SOLUTION: In a grease supply method, grease 12 for replacing existing grease filling a clearance 11 between a rotary shaft 23 and a slide bearing 1 of the rotary shaft 23 is supplied. In the grease supply method, the clearance 11 and a supply pump P for sending the grease 12 to the clearance 11 communicate with each other through a supply pipe S with a chamber C provided in its middle part. A supply amount of the grease 12 is adjusted based on a measured internal pressure of the chamber C.SELECTED DRAWING: Figure 2

Description

The present invention relates to a grease supply method and a grease supply system.

Conventionally, there is a sliding bearing lubrication management method for construction machinery that intermittently supplies grease to sliding bearings provided in joints of a multi-joint front of construction machinery (Patent Document 1).

JP 2011-162944 A

However, the conventional greasing method is based on the premise of directly detecting the temperature of the sliding bearing using a special sliding bearing with an embedded temperature sensor.

An object of the present invention is to provide a grease supply method and a grease supply system capable of increasing the durability of a slide bearing.

The present invention has the following aspects.
(1) A grease supply method according to one aspect of the present invention is a grease supply method for supplying grease to replace existing grease filled in a clearance between a rotating shaft and a slide bearing of the rotating shaft, wherein the clearance and , a supply pump for sending the grease to the clearance is communicated with a supply pipe provided in the middle of the chamber, and the supply amount of the grease is adjusted based on the measured internal pressure of the chamber.
(2) A grease supply system according to one aspect of the present invention is a grease supply system that supplies grease to replace existing grease filled in a clearance between a rotating shaft and a sliding bearing of the rotating shaft, wherein the grease is a supply pump that delivers power to the clearance; a supply pipe that communicates between the clearance and the supply pump; a chamber provided in the middle of the supply pipe; a pressure gauge that measures the internal pressure of the chamber; a control device for controlling, wherein the control device controls the supply pump based on the internal pressure.
(3) In (2) above, the supply pump is a positive displacement pump that intermittently delivers the grease, and the control device controls that an increase in the internal pressure per delivery of the grease exceeds an increase threshold value. The amount supplied per delivery may be controlled so that there is no
(4) In (2) or (3) above, the supply pump is a positive displacement pump that intermittently delivers the grease, and the controller controls the maximum value of the internal pressure per one delivery of the grease. The amount delivered per delivery may be controlled so that the internal pressure threshold is not exceeded.
(5) In (2) above, the control device may control the supply flow rate of the grease so that the increase in the internal pressure does not exceed an increase threshold.

ADVANTAGE OF THE INVENTION According to this invention, the grease supply method and grease supply system which can improve durability of a slide bearing can be provided.

1 is an explanatory diagram of a grease supply system according to an embodiment; FIG. It is explanatory drawing of a slide bearing. FIG. 4 is a diagram showing the relationship between the temperature of the slide bearing and the internal pressure of the chamber;

[Embodiment]
A grease supply method and a grease supply system 100 according to an embodiment will be described below. FIG. 1 is an explanatory diagram of a grease supply system 100 according to an embodiment. FIG. 2 is an explanatory diagram of the slide bearing 1. FIG. FIG. 3 is a diagram showing the relationship between the temperature of the slide bearing 1 and the internal pressure of the chamber.

(Grease supply method)
As shown in FIG. 1, the grease supply method according to the embodiment can be applied to, for example, a pump 200 such as a water pump that pumps up fluid such as water against gravity.
The pump 200 includes a tube 20 through which fluid such as water flows, a rotating shaft 23 extending along a tube axis 21 of the tube 20 and having an impeller 22 , and a motor 24 for rotating the rotating shaft 23 . The rotary shaft 23 is rotatably supported by the plain bearing 1 . The clearance between the rotating shaft 23 and the slide bearing 1 is filled with existing grease. Hereinafter, the term "grease" refers to a semi-solid or solid material obtained by dispersing a soap-based or non-soap-based thickening agent in a raw material base oil.

As shown in FIGS. 1 and 2, the grease supply method according to the embodiment supplies grease 12 to replace the existing grease filled in the clearance 11 between the rotating shaft 23 and the sliding bearing 1 of the rotating shaft 23. be. In the grease supply method, first, the clearance 11 and the supply pump P for sending the grease 12 to the clearance 11 are communicated with each other through the supply pipe S provided with the chamber C in the middle.

Here, the relationship between the temperature of the slide bearing 1 and the internal pressure of the chamber C was investigated.
FIG. 3 is a diagram showing the relationship between the temperature of the slide bearing 1 and the internal pressure of the chamber C. As shown in FIG. In FIG. 3, the horizontal axis is time t (hours:minutes:seconds), the left vertical axis is the temperature rise amount ΔT (° C.), and the right vertical axis is the internal pressure of the chamber C (kPa). 3, the thick line represents the temperature of the plain bearing 1 (the temperature of the grease filled in the clearance 11), and the thin line represents the internal pressure of the chamber C. As shown in FIG.
The temperature of the grease filled in the clearance 11 of the slide bearing 1 is measured with a thermocouple while the rotating shaft 23 supported by the slide bearing 1 is rotated at a constant number of revolutions, and the internal pressure of the chamber C is measured by the Bourdon tube pressure. measured with a meter.
First, the supply amount of the grease 12 per delivery was set to the first supply amount (for example, 200 cc) by the supply pump P, which is a positive displacement pump, and delivery was started at 0:12:00 (S1). . Then, the grease 12 was intermittently delivered once every 6 minutes until 1 hour 42 minutes 00 seconds (S2). After that, the pressure was reduced (S3).
Next, the supply amount of the grease 12 per delivery was set to a second supply amount (for example, 400 cc) that is twice the first supply amount, and delivery was started from 2:12:00 (S4 ). Then, the grease 12 was intermittently delivered once every 6 minutes until 2:48:00 (S5). After that, the pressure was reduced (S6).
As a result, as shown in FIG. 3, it was confirmed that there is a positive correlation between the temperature of the slide bearing 1 and the internal pressure of the chamber C (or the maximum value of the internal pressure per delivery). It was also confirmed that when the first supply amount is supplied at a predetermined frequency, the temperature rise can be suppressed more than when the second supply amount is supplied at the same frequency.
Thus, it has been found that the temperature of the slide bearing 1 and the internal pressure of the chamber C have a positive correlation when the grease 12 is supplied to the clearance 11 filled with the existing grease. Therefore, it was found that the supply amount or supply flow rate of the grease 12 should be adjusted so that the internal pressure of the chamber C does not rise significantly in order to prevent the temperature of the slide bearing 1 from rising significantly.

Therefore, the grease supply method according to the embodiment adjusts the supply amount of the grease 12 based on the measured internal pressure of the chamber C. FIG. For example, when the internal pressure of the chamber C increases when supplying the grease 12, the temperature of the slide bearing 1 is high. The supply amount of the grease 12 is reduced by, for example, changing to one with a smaller supply amount (volume) of the grease 12 per unit.
Thus, in the grease supply method according to the embodiment, the supply amount of the grease 12 is adjusted based on the internal pressure of the chamber C, which has a positive correlation with the temperature of the slide bearing 1 . Therefore, it is not necessary to directly measure the temperature of the plain bearing 1 . Therefore, it is possible to simplify the structure and reduce the risk of failure without making the sliding bearing 1 into something special such as one with an embedded temperature sensor. Also, the grease 12 that replaces the existing grease filled in the clearance 11 can be adjusted to an appropriate amount and sent by the supply pump P. Therefore, it is possible to suppress adverse effects caused by the temperature rise of the sliding bearing 1, including seizure of the rotary shaft 23 and reduction in the life of the oil seal. Therefore, it is possible to provide a grease supply method capable of increasing the durability of the slide bearing 1 .

The supply amount of the grease 12 may be adjusted by changing the delivery frequency obtained by dividing the number of deliveries by time when the supply pump P is a positive displacement pump and the volume per delivery by the positive displacement pump is fixed.
If the supply pump P is a positive displacement pump and the frequency of delivery by the positive displacement pump is fixed, the amount of grease 12 supplied may be adjusted by changing the capacity per delivery by the positive displacement pump.
The supply amount of the grease 12 may be adjusted by changing the flow rate of the grease 12 when the supply pump P is a variable flow rate pump.

(Grease supply system)
Next, the grease supply system 100 according to the embodiment will be described.
As shown in FIG. 1, the grease supply system 100 according to the embodiment can be applied to, for example, a pump 200 such as a water pump that pumps up fluid such as water against gravity. The pump 200 includes a tube 20 through which fluid such as water flows, a rotating shaft 23 extending along a tube axis 21 of the tube 20 and having an impeller 22 , and a motor 24 for rotating the rotating shaft 23 .

As shown in FIGS. 1 and 2, the rotary shaft 23 is rotatably supported by the slide bearing 1. As shown in FIG. The slide bearing 1 receives radial force from the rotating shaft 23 . In addition to being supported by the slide bearing 1, the rotary shaft 23 may be supported by a bearing other than the slide bearing 1 as appropriate.

As shown in FIGS. 1 and 2, the grease supply system 100 supplies grease 12 to replace the existing grease filled in the clearance 11 between the rotating shaft 23 and the slide bearing 1 of the rotating shaft 23 . The grease supply system 100 includes a supply pump P that delivers the grease 12 to the clearance 11, a supply pipe S that communicates between the clearance 11 and the supply pump P, a chamber C provided in the middle of the supply pipe S, and the chamber C. A pressure gauge B for measuring the internal pressure and a control device 30 for controlling the supply pump P are provided.

The plain bearing 1 is arranged in a flow path inside a pipe 20 and is supported by the pipe 20 or the like. and a seal 15 that seals between both ends of the casing 13 in the axial direction and the rotating shaft 23 .

The casing 13 and the bush 14 each have a through hole 16 penetrating from the supply pipe S to the clearance 11 . A plurality of through holes 16 may be provided in the circumferential direction of the sliding bearing 1 at regular intervals, for example. When there are a plurality of through holes 16 , the supply pipe S may be branched from the chamber C to correspond to each through hole 16 .

Since the slide bearing 1 has the structure described above, the grease 12 supplied from the supply pipe S passes through the through hole 16 as indicated by the arrow in FIG. 23 , replaces the existing grease, and fills the clearance 11 .

The grease 12 is semi-solid or solidified by dispersing a soap-based or non-soap-based thickening agent in the raw material base oil. Grease 12 fills the passage from clearance 11 to chamber C. As shown in FIG.

The supply pipe S communicates with the chamber C and a through hole 16 provided in the casing 13 of the slide bearing 1 . A plurality of supply pipes S may be provided according to the number of through holes 16 . The supply pipe S may be branched into a plurality of branches according to the number of through holes 16 .

The chamber C is a chamber having an internal space that is continuous with the flow path of the supply pipe S. The chamber C is provided in the middle of the supply pipe S, that is, between the supply pump P and the plain bearing 1 .

A pressure gauge B measures the internal pressure of the chamber C. The pressure gauge B is, for example, a Bourdon tube pressure gauge. Since the pressure gauge B measures the internal pressure of the chamber C, it can measure the pressure of the grease 12 filled in the flow path from the clearance 11 of the slide bearing 1 to the chamber C. Data on the internal pressure of the chamber C measured by the pressure gauge B is sent to the controller 30 .

The supply pump P is a pump that supplies the grease 12 to the slide bearing 1 . Feed pump P may be, for example, a positive displacement pump, a non-displacement pump, or a variable flow pump. The supply pump P can change the supply amount or supply flow rate of the grease 12 by, for example, changing the structure of the supply pump P (capacity corresponding to the supply amount per delivery, etc.) and the supply speed (delivery pitch, rotation speed, etc.). can be adjusted. The supply pump P may be configured so that the supply amount or supply flow rate of the grease 12 can be controlled by the controller 30 .

The control device 30 controls the supply amount or supply flow rate of the grease 12 by controlling the supply pump P. FIG. The control device 30 has a memory and a CPU. In addition to the program, the memory stores preset internal pressure thresholds or incremental thresholds. The memory temporarily stores the internal pressure measured by the pressure gauge B at predetermined time intervals. According to the program, the control device 30 calls the internal pressure and the internal pressure threshold value or the incremental threshold value from the memory and compares the internal pressure with the internal pressure threshold value. Alternatively, the control device 30 compares the internal pressure increment ΔP and the increment threshold from the memory according to the program. Then, the control device 30 controls the supply pump P based on the result of the comparison. For example, when the internal pressure exceeds the internal pressure threshold, the drive of the supply pump P is stopped to stop the supply of the grease 12 . For example, when the internal pressure exceeds the internal pressure threshold and then falls below the internal pressure threshold, the supply pump P is driven again to restart the supply of the grease 12 .

Thus, the control device 30 controls the supply pump P based on the internal pressure of the chamber C. As shown in FIG.
That is, in the grease supply system 100 according to the embodiment, the controller 30 controls the supply pump P based on the internal pressure of the chamber C, which has a positive correlation with the temperature of the slide bearing 1 . Therefore, it is not necessary to directly measure the temperature of the plain bearing 1 . Therefore, it is possible to simplify the structure and reduce the risk of failure without making the sliding bearing 1 into something special such as one with an embedded temperature sensor. Also, the grease 12 that replaces the existing grease filled in the clearance 11 can be adjusted to an appropriate amount and sent by the supply pump P. Therefore, it is possible to suppress adverse effects caused by the temperature rise of the sliding bearing 1, including seizure of the rotary shaft 23 and reduction in the life of the oil seal. Therefore, it is possible to provide the grease supply system 100 that can improve the durability of the slide bearing 1 .

The supply pump P may be a positive displacement pump that intermittently delivers the grease 12 . Then, the controller 30 may control the supply amount per delivery so that the increment ΔP (see FIG. 3) of the internal pressure of the chamber C per delivery of the grease 12 does not exceed the increment threshold. For example, the increment threshold is set to 20 kPa in advance, and the control device 30 controls the supply amount of the grease 12 per feeding by the supply pump P so that the increment of the internal pressure of the chamber C does not exceed this increment threshold. to control. As a result, an appropriate amount of grease 12 can be supplied to the clearance 11 of the slide bearing 1 at an appropriate frequency while suppressing an increase in the temperature of the slide bearing 1 .

The supply pump P may be a positive displacement pump that intermittently delivers the grease 12 . Then, the controller 30 may control the supply amount per delivery so that the maximum value Pmax (see FIG. 3) of the internal pressure of the chamber C per delivery of the grease 12 does not exceed the internal pressure threshold. For example, the internal pressure threshold is set to 60 kPa in advance, and the controller 30 supplies the grease 12 per feeding by the supply pump P so that the maximum value Pmax of the internal pressure of the chamber C does not exceed this internal pressure threshold. control the amount. As a result, an appropriate amount of grease 12 can be supplied to the clearance 11 of the slide bearing 1 at an appropriate frequency while suppressing an increase in the temperature of the slide bearing 1 .

Also, the control device 30 may control the supply flow rate of the grease 12 so that the increase in the internal pressure of the chamber C does not exceed the increase threshold. Here, the supply flow rate is the supply amount supplied per unit time. For example, the increment threshold is set to 20 kPa in advance, and the control device 30 controls the supply flow rate of the grease 12 by the supply pump P so that the increment ΔP of the internal pressure of the chamber C does not exceed this increment threshold. As a result, regardless of the structure of the supply pump P, such as a displacement type, a non-displacement type, or a variable displacement type, the grease 12 can be supplied to the clearance 11 of the slide bearing 1 at an appropriate flow rate while suppressing the temperature rise of the slide bearing 1. can be supplied by

Although the embodiments have been described above with reference to the drawings, the present invention is not limited to the above. A plurality of features given as embodiments may be freely combined.

The grease supplying method according to the present embodiment supplies the grease 12 that replaces the existing grease filled in the clearance 11 between the rotating shaft 23 and the slide bearing 1 of the rotating shaft 23 . In the grease supply method, the clearance 11 and the supply pump P for delivering the grease 12 to the clearance 11 are communicated with each other through the supply pipe S with the chamber C provided in the middle. Then, based on the measured internal pressure of the chamber C, the supply amount of the grease 12 is adjusted. As a result, the sliding bearing 1 does not need to be made special such as having an embedded temperature sensor, so that the structure can be simplified and the risk of failure can be reduced. Also, the grease 12 that replaces the existing grease filled in the clearance 11 can be adjusted to an appropriate amount and sent by the supply pump P. Therefore, it is possible to suppress adverse effects caused by the temperature rise of the sliding bearing 1, including seizure of the rotary shaft 23 and reduction in the life of the oil seal. Therefore, it is possible to provide a grease supply method capable of increasing the durability of the slide bearing 1 .

A grease supply system 100 according to the present embodiment supplies grease 12 to replace existing grease filled in a clearance 11 between a rotating shaft 23 and a slide bearing 1 of the rotating shaft 23 . The grease supply system 100 includes a supply pump P that delivers the grease 12 to the clearance 11, a supply pipe S that communicates between the clearance 11 and the supply pump P, a chamber C provided in the middle of the supply pipe S, and the chamber C. A pressure gauge B for measuring the internal pressure and a control device 30 for controlling the supply pump P are provided. Then, the control device 30 controls the supply pump P based on the internal pressure. As a result, the sliding bearing 1 does not need to be made special such as having an embedded temperature sensor, so that the structure can be simplified and the risk of failure can be reduced. Also, the grease 12 that replaces the existing grease filled in the clearance 11 can be controlled to an appropriate amount and delivered by the supply pump P. Therefore, it is possible to suppress adverse effects caused by the temperature rise of the sliding bearing 1, including seizure of the rotary shaft 23 and reduction in the life of the oil seal. Therefore, it is possible to provide the grease supply system 100 that can improve the durability of the slide bearing 1 .

1 Bearing 11 Clearance 12 Grease 13 Casing 14 Bush 15 Seal 16 Through hole 20 Pipe 21 Pipe shaft 22 Impeller 23 Rotating shaft 24 Motor 30 Control device 100 Grease supply system 200 Pump B Pressure gauge C Chamber P Supply pump S Supply pipe

Claims (5)

A grease supply method for supplying grease to replace existing grease filled in a clearance between a rotating shaft and a slide bearing of the rotating shaft, comprising:
the clearance and a supply pump for sending the grease to the clearance are communicated with each other through a supply pipe having a chamber in the middle;
A grease supply method, comprising: adjusting the supply amount of the grease based on the measured internal pressure of the chamber. A grease supply system for supplying grease to replace existing grease filled in a clearance between a rotating shaft and a sliding bearing of the rotating shaft,
a supply pump that delivers the grease to the clearance;
a supply pipe communicating between the clearance and the supply pump;
a chamber provided in the middle of the supply pipe;
a pressure gauge that measures the internal pressure of the chamber;
a control device that controls the supply pump,
The grease supply system, wherein the controller controls the supply pump based on the internal pressure. The supply pump is a positive displacement pump that intermittently delivers the grease,
3. The grease supply system according to claim 2, wherein the control device controls the supply amount per delivery so that the increment of the internal pressure per delivery of the grease does not exceed an increment threshold. . The supply pump is a positive displacement pump that intermittently delivers the grease,
4. The controller according to claim 2 or 3, wherein the controller controls the supply amount per delivery of the grease so that the maximum value of the internal pressure per delivery of the grease does not exceed an internal pressure threshold value. Grease supply system as described. 3. The grease supply system according to claim 2, wherein the controller controls the supply flow rate of the grease so that the increment of the internal pressure does not exceed an increment threshold.

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