JP2003056574A - Solid lubrication bearing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solid lubrication bearing device whose service life can be accurately estimated without adding a special structure to the device or performing previous check, when assembling in the device a bearing to be lubricated by a solid lubricant. SOLUTION: A sensor head 41 for a particle counter 4 for counting particles dusted by contact between a roller 13, and a raceway surface is assembled in the vicinity of a position between the roller 13 of the solid lubrication bearing 1 and its raceway surface in accordance with a predetermined positional relation with respect to the roller 13 and its raceway surface. Thus, a certain relation, between the measurement result of a dusting amount by the particle counter 4 and the condition of the bearing, is established. Accurate information about the service life running short can be given to a user at this time, by merely assembling the bearing in the device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid lubricating bearing device which uses a solid lubricant to lubricate between rolling elements and their raceways. Here, the bearing device in the present invention includes not only a normal bearing device that rotatably supports a shaft, but also a so-called linear motion type bearing (linear bearing) and a ball screw that linearly move a member. Say

[0002]

2. Description of the Related Art In equipment used in a special environment such as a vacuum environment or a clean room, various solid lubricants such as a fluorine-based polymer lubrication thin film are used to lubricate the bearings of its rotating and linear motion parts. Agents are often used. Specifically, the rolling element surface and its raceway surface are coated with a thin film made of a solid lubricant.

By the way, in a normal rolling bearing or linear motion bearing which is lubricated with grease or oil, abnormal noise or vibration is usually generated before the tone of rotation is deteriorated. It is possible to detect that the life is approaching due to the occurrence. On the other hand, in the bearing lubricated by the solid lubricant as described above, the rotation may be suddenly disabled (locked state) without a sign of such abnormal noise or vibration, which makes it difficult to predict the service life. is there. Therefore, a device incorporating such a bearing may have an unexpected stop accident or breakage due to sudden locking, which makes maintenance difficult.

It is known that the life of a bearing lubricated by such a solid lubricant can be predicted from changes in the amount of dust generated.

That is, for example, JP-A-8-226446.
In the gazette, a rolling bearing and its raceway surface coated with a solid lubricant are coated with a fluorine-based polymer lubricating thin film to rotate a rolling bearing under a predetermined load in a casing, and the casing is removed except for a clean air inlet. There is an example of measuring the life of the rolling bearing, that is, the life of dust generation, by sealing with a magnetic fluid seal, sucking the atmosphere in the casing and guiding it to a particle counter, and observing the amount of dust generation of the rolling bearing over time. It is disclosed.

[0006]

By the way, measuring the dust generation life of a bearing lubricated by a solid lubricant as described above by using a particle counter is experimentally conducted as described in the above publication. However, there is a problem as described below in order to predict the life of the bearing by measuring the amount of dust generated in the actual usage state of the bearing. That is, in the device in which the bearing is installed,
It is not only necessary to add a structure for measuring the amount of dust generated by a particle counter, but also a structure for measuring the amount of dust generated, more specifically, the bearing and the measurement position of the amount of dust generated, and the sealing form. After deciding the bearing, the bearing life cannot be predicted unless the relationship between the dust generation amount and the bearing state is investigated in advance according to the positional relationship and the sealing form.Therefore, it is necessary to investigate this relationship for each device. There is. Further, since the above-mentioned investigation involves a bearing life test and measurement of the amount of dust generation, it requires a high level of skill, knowledge, time, and man-hours, which poses a problem that it is a great burden for general users.

The present invention has been made in view of the above circumstances, and when the bearing lubricated by the solid lubricant is actually incorporated and used in the apparatus, the structure change for measuring the dust generation amount as described above is performed. Another object of the present invention is to provide a solid lubrication bearing device capable of accurately predicting the life of the bearing without conducting a preliminary investigation or the like.

[0008]

In order to achieve the above object, a solid lubrication bearing device of the present invention comprises a rolling element and its raceway surface, and lubricates the rolling element and the raceway surface with a solid lubricant. In a solid lubricating bearing device configured to perform, in the vicinity of the rolling element and its raceway surface,
A sensor head of a particle counter for counting particles generated by the contact between the rolling element and the raceway surface is incorporated in a predetermined positional relationship with the rolling element and the raceway surface. (Claim 1).

Here, in the present invention, a configuration is provided in which the output of the particle counter is introduced and compared with prestored data to provide information about the life of the rolling bearing device (claim). 2) can be suitably adopted. The present invention intends to predict the life of a solid lubrication bearing device by utilizing the dust generation characteristics of the solid lubrication bearing device. Moreover, the sensor head for measuring the dust generation amount has a fixed positional relationship with the bearing. By incorporating it in advance, it is intended to achieve the intended purpose.

That is, in a bearing in which the surface of the rolling element and its raceway surface are covered with a solid lubricant, as shown in the graph qualitatively in FIG. By performing familiar operation, the amount of dust generated decreases, and the state of stable small amount of dust continues. Then, after a certain period of time has elapsed, the dust generation amount increases rapidly. Further, it is known that when the amount of dust generation increases, particles having a larger particle size than the dust particles generated so far are generated. This is because direct contact between the base materials due to the disappearance of the lubricating film, And the occurrence of wear. The phenomenon of increasing the amount of dust generation always appears before the rotational condition of the bearing deteriorates, and therefore, this phenomenon is called the dust generation life. Already known.

Here, the measurement result of the dust generation amount as described above,
That is, in order to predict the life of the bearing using the measurement result of the number of dust particles per unit time or per unit atmosphere volume, the dust amount of the bearing is measured at a certain position,
As described above, it is necessary to investigate the relationship between the measurement result and the state of the bearing.

Therefore, in the present invention, a sensor head of a particle counter for counting particles flying due to contact between the rolling element and the raceway is provided in the vicinity of the rolling element and the raceway of the solid lubrication bearing. By incorporating in the bearing device in advance with a predetermined positional relationship between the rolling element and the raceway surface, the relationship between the measurement result of the dust generation amount and the state of the bearing is always constant, and therefore the present invention is concerned. When incorporating the bearing device into the device, the user does not need to separately provide a structure for measuring the dust generation amount on the device side, it can be handled as easily as a normal rolling bearing, and the dust generation amount and bearing There is no need to investigate the relationship with the condition. Here, the above-mentioned predetermined positional relationship is a concept including a general mounting method that affects the measurement result by the sensor, such as the shape, mounting angle, and position of the sensor head.

According to the second aspect of the present invention, the output of the particle counter is compared with pre-stored data, for example, a threshold value, and based on the comparison result, information about the life, that is, the remaining life is short. It is possible to accurately know that the bearing has reached the replacement time by providing an informing means for informing, for example, by a lamp or the like whether or not the bearing has been replaced.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram of an embodiment of the present invention, and is a diagram in which a cross-sectional view showing a mechanical configuration of a main part and a block diagram showing an electrical configuration are shown together.

In this example, the present invention is applied to a solid lubrication rolling bearing 1 that supports a shaft 2. The inner ring 11, the outer ring 12, a plurality of balls 13, and each ball 13 are held at regular intervals in the circumferential direction. In the solid lubrication rolling bearing 1 including the cage 14, the raceways of the inner ring 11 and the outer ring 12 and the surface of each ball 13 are coated with a lubricating coating containing, for example, a fluoropolymer.

The outer ring 12 of the rolling bearing 1 is formed with a groove 12a on the outer diameter surface on one end surface side thereof, and the sensor holding member 15 is fixed to the groove 12a. The sensor holding member 15 has an annular shape as a whole, and has a substantially U-shaped cross section in which convex portions 15b and 15c are formed on the outer peripheral side and the inner peripheral side of the disc portion 15a, respectively.
5b is fixed by being fitted in the groove 12a of the outer ring 12. Further, the inner peripheral side convex portion 15c is the inner ring 1
The end faces of 1 are opposed to each other with a slight gap. The material of the sensor holding member 15 is not particularly limited,
For example, resin, rubber, or soft metal can be used.

Then, the sensor head 41 of the particle counter 4 is attached to the disk portion 15a of the sensor holding member 15.
Are fixed to the raceways of the inner and outer races 11 and 12 of the solid lubrication rolling bearing 1 and the rolling elements 13 in a fixed positional relationship. The particle counter 4 sucks a constant atmosphere per unit time into the particle counter main body 42 via the sensor head 41, and counts the number of particles within a preset particle size range among the particles contained in the atmosphere. The number of particles contained in a fixed volume of the sucked atmosphere is sequentially counted, and the counting result is output at fixed time intervals.

The counting output of the particle counter 4 at regular intervals is introduced to the comparator 5. In the comparator 5,
The count output is compared with a preset threshold value, and when the count output by the particle counter 4 exceeds the threshold value, a contact output is supplied to the notification lamp 6 to turn on the notification lamp 6. Is configured. The output of the comparator 5 can be supplied to the outside via the signal output unit 5a in addition to the notification lamp 6, and the output of the comparator 5 can be used for various controls of other devices and remote control. It is also possible to display different display means.

In the above embodiment, the solid lubrication rolling bearing 1 in which the sensor head 41 is integrally incorporated with the rolling bearing 1 in a prescribed positional relationship is subjected to a predetermined running-in operation. For example, in FIG. 4 described above, after the accustomed operation until the cumulative number of revolutions reaches n ₀ , the accumulator is incorporated into the equipment and put to practical use. Therefore, the amount of dust generated after being actually used is small and stable,
Immediately before reaching the end of its life, the amount of dust generation increases rapidly. In addition, the particle diameter range in which the amount of dust is particularly increased when the remaining life is short is the same in the solid lubrication rolling bearing having the same type of structure, and therefore the particle counter 4
The particle size range counted by is set to the particle size range. When the positional relationship between the solid lubrication rolling bearing 1 having the same structure and the sensor head 41 is constant, the amount of dust generated and the state of the bearing have a substantially constant relationship. The amount of dust can be investigated in advance by the bearing manufacturer, and the threshold value of the comparator 5 is set as a value corresponding to the level ε in the example of FIG. 4 based on the survey result.

Therefore, by merely incorporating the solid lubrication rolling bearing device according to the above-described embodiment of the present invention into the equipment, the notification lamp 6 is turned on immediately before the solid lubrication rolling bearing 1 reaches the end of its life. By replacing the solid lubrication rolling bearing 1 when 6 is turned on,
Can be prevented from falling into a non-rotatable state.

Here, in the above embodiment, an example of using the open type without a seal as the solid lubrication rolling bearing 1 has been shown, but the present invention also applies to a sealed type using a seal. Can be applied. In that case, since one end surface of the bearing 1 is substantially sealed by the sensor holding member 15, it suffices to mount a seal on the other end surface side, and it is sealed with the open type in the above-described embodiment. In the type, even if the sensor head 41 is incorporated under the same positional relationship, the measurement result of the dust generation amount is different. Therefore, the bearing manufacturer may set the threshold value of the comparator 5 by individually examining the relationship between the dust generation amount and the bearing state for each of the open type and the sealed type.

In the above embodiment, the present invention is applied to the solid lubrication rolling bearing that rotatably supports the shaft 2. However, the present invention shows that the linear motion bearing member that linearly moves is supported. It is equally applicable to bearings, an example of which is shown in FIG.
And shown in FIG. FIG. 2 is a configuration diagram of this embodiment and shows a side view showing a mechanical configuration and a block diagram showing an electrical configuration together. Further, FIG. 3 is a partially cutaway perspective view of the solid lubricating linear motion bearing 7 in this embodiment.

As shown in FIG. 3, the solid-lubricated linear motion bearing 7 in this example is mainly composed of a linear rail 71, a block 72 having a substantially U-shaped cross section, a plurality of balls 73, and a pair of side plates 74a and 74b. And the track surfaces of the balls 73 are formed on both side surfaces of the rail 71 and both inner side surfaces of the block 72, respectively.
On both sides of the rail, the track surface of the rail 71 and the block 7
It is installed so as to make rolling contact with both of the two raceway surfaces. Then, the same lubrication film made of the fluoropolymer as in the above-described embodiment is applied to the raceways of the rail 71 and the block 72 and the surface of each ball 73.

As shown in FIG. 2, a sensor support member 16 is fixed to one of the rails 71 of the solid-lubricated linear motion bearing 7 at the central portion in the longitudinal direction of the rail 71. The sensor head 41 of the particle counter 4 equivalent to that used in the embodiment is provided with the rail 71.
It is connected to the particle counter main body 42 while being fixed in a fixed positional relationship with respect to the orbital surface on one side. Also, the particle counter body 4
The counting output from 2 every fixed time is also introduced into the comparator 5 equivalent to the previous example and compared with the threshold value, and when the counting output exceeds the threshold value, the notification lamp 6 is turned on. Has become. Further, the signal can be supplied to the outside through the signal output unit 5a of the comparator 5, and the output thereof can display various controls of other devices and display means placed at a remote position. Has become.

Also in this example, the solid lubrication linear motion bearing 7 is used.
Is incorporated into the equipment after the familiar operation until the cumulative movement distance in FIG. 4 reaches n ₀ , maintains a small amount of dust generation at the beginning of operation of the equipment, and suddenly emits when the life becomes short. The amount of dust increases. The dust generation characteristics are investigated in advance by the bearing manufacturer with the sensor head 41 fixed under the above-described fixed positional relationship with the solid-lubricated linear motion bearing 7, and particularly when the life is short, The particle size range measured by the particle counter 4 is set in the particle size range where the amount of dust increases, and the comparator 5
The threshold value of is also preset to a value corresponding to the level ε in the example of FIG.

Therefore, also in this embodiment, the user simply installs the solid lubrication bearing device of this embodiment into the equipment, and the indicator lamp 6 is turned on when the life of the solid lubrication linear motion bearing 7 becomes short. As a result, it is possible to know that the solid lubricating linear motion bearing 7 has reached the replacement time.

In each of the above embodiments, the count output of the particle counter 4 is compared with the threshold value by the comparator 5, and the notification lamp 6 is turned on when the count output exceeds the threshold value. Although an example has been shown in which the bearing is urged to be replaced, the notifying means is not limited to a lamp, and any form can be used, and further, without using such a comparator and notifying means. , The particle counter 4 may be configured to display the counting result. In this case, the equipment administrator or the like may have to replace the bearing when the displayed value becomes larger than a predetermined limit. Can know that has arrived.

Further, the present invention can be equally applied to a ball screw having a rolling element and its raceway surface, as in the above-mentioned respective embodiments.

[0029]

As described above, according to the present invention, the sensor head of the particle counter is installed in the vicinity of the solid lubrication rolling bearing or the solid lubrication linear motion bearing in a predetermined positional relationship, and dust is generated from the bearing. Since the particles are counted at a fixed position, the relationship between the count result and the state of the bearing is always a fixed relationship, and the user simply installs the bearing device according to the present invention in the device, and based on the counting result by the particle counter. The life expectancy can be estimated.

As a result, the user cannot use the bearing-incorporating device without special processing or the like, and without conducting any prior investigation, without generating abnormal noise or vibration as in the conventional case. However, if you replace the solid lubrication bearing that had been replaced in a normal state because of the fear of it, the solid lubrication bearing should be accurately It became possible to exchange.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention, in which a cross-sectional view showing a mechanical configuration and a block diagram showing an electrical configuration are shown together.

FIG. 2 is a configuration diagram of another embodiment of the present invention, in which a side view showing a mechanical configuration and a block diagram showing an electrical configuration are shown together.

FIG. 3 is a partially cutaway perspective view of a solid lubrication direct acting bearing used in the embodiment of FIG.

FIG. 4 is a graph showing an example of dust generation characteristics of a solid lubrication bearing.

[Explanation of symbols] 1 Solid lubrication rolling bearing 11 inner ring 12 outer ring 13 balls 14 cage 15, 16 Sensor holding member 2 axes 3 housing 4 particle counter 41 sensor head 42 Particle counter body 5 comparator 5a Signal output section 6 Notification lamp 7 Solid lubrication linear motion bearing 71 rail 72 blocks 73 balls 74a, 74b side plates

Claims (2)

[Claims] 1. A rolling element and its raceway surface are provided, and
A solid lubrication bearing device configured to perform lubrication between the rolling element and the raceway surface by a solid lubricant, wherein dust is generated in the vicinity of the rolling element and the raceway surface due to contact between the rolling element and the raceway surface. A solid lubricating bearing device, characterized in that a sensor head of a particle counter for counting the number of particles formed is incorporated in a predetermined positional relationship with the rolling elements and the raceway surface. 2. An informing unit for informing the information about the life of the bearing device by introducing the output of the particle counter and comparing it with data stored in advance. The solid lubricating bearing device described.