JPS61149697A - Automatic oiling device - Google Patents

Abstract

PURPOSE:To discharge a designated quantity of lubricating oil at a fixed period at need by providing a piezoelectric device on a piston in a lubricating oil container, and applying designated voltage to the piezoelectric device to move the piston by a very small amount. CONSTITUTION:Designated voltage is applied to a fixing electric element 21 to be displaced in the diametral direction, and the fixing piezoelectric element 21 is fixed in a lubricating oil container 10. Subsequently, designated pressure is applied to a main power piezoelectric element 22 to be displaced in the axial direction, whereby to press a piston pressing piezoelectric element 23 brought into contact with the main power piezoelectric element 22. Whereupon, a piston 11 brought into contact with the piston pressing piezoelectric element 23 moves by a very small amount. This movement causes grease 13 sealed in below the piston 11 to be discharged from a lubricating oil discharge port 15.

Description

[Detailed description of the invention] [Technical field of invention] The present invention relates to a screw lower part provided in a lubricating oil container.

is moved by a small amount by the pressing means, and the movement of the piston □ causes the above rs? The present invention relates to an automatic oil supply device that discharges lubricating oil in an oil container from a lubricating oil outlet, and particularly relates to improvements in the above-mentioned pressing means.

[Technical Background of the Invention and Problems Therewith] Generally, rotating bearings such as ball bearings and O-La bearings are supplied with lubricating oil and grease. The above grease needs to be replaced depending on its lifespan.For example, in the case of the ball bearing, the replacement period T due to the lifespan of the grease is T-A (10S/N(τ)X(-18d)...(
1) is used as a guideline. In the above equation (1), A is a constant, N is the rotation speed, and d is the bearing inner diameter. For example, rotation speed N
For ball bearings with N-1800 rpm and bearing inner diameter d = 50 ai, the grease should be replaced after about 4000 hours.

When replacing the grease, new grease is normally supplied from the side of the bearing and old grease is discharged from the discharge port. At this time, the amount of grease supplied is smaller than that of the discharge layer, and may be about 1/2 of the bearing area. That is, for a ball bearing with a bearing inner diameter of d-50, the initial filling amount (at the time of assembly) is 500, whereas the replenishment amount is about 30°.

In addition, as a means of replenishing the grease, there is also a method of manually replenishing with a grease gun, but in areas where many rotating machines are used, such as in chemical plants, a piston in a grease container filled with grease is used. Automatic lubricating means is common, in which the grease is continuously discharged little by little over a long period of time by moving a small amount by increasing gas pressure due to a chemical change or by using a pressing means made of spring force.

FIG. 7 is a sectional view showing a state in which the conventional automatic oil supply device 1 is attached to a rotating machine. In FIG. 7, a bearing 3 fitted onto a shaft 2 of a rotating machine is supported by a bearing bracket 4. A seal bracket 5 for preventing oil leakage to the outside is provided on one surface of the bearing bracket 4, and a seal cover 6 for fixing the bearing is provided on the other surface. A IIIWI oil passage 7 is formed by the seal bracket 5 and the seal cover 6.

In this way, new grease supplied from the automatic lubrication device 1 passes through the me oil conduit 8 to the lubricating oil passage 7, and is supplied to the bearing 3 through this passage 7. On the other hand, the old grease filled in the bearing 3 is washed away by the pressure of new grease supplied from the automatic lubrication device 1, and is stored in the S oil reservoir 9 provided in the seal cover 6. It has become.

FIG. 8 is a sectional view showing the structure of the automatic refueling bag H1. In FIG. 8, there is a piston 1 in the lubricating oil container 10.
1 is provided, and the space between this piston 11 and the lubricating oil container 10 is sealed by an O-ring 12.

Grease 13 is sealed in the lower part of the piston 11, and a pressing mechanism 14 is provided in the upper part of the piston 11 to discharge the grease 13 little by little. The pressing mechanism 14 may include, for example, a piece of aluminum (Aj2) and a liquid that melts the AJ2 piece to generate gas, and the piston is slightly pushed by the gas pressure generated by the chemical change between the AJ2 piece and the liquid. The piston 11 is moved by a small amount, or a spring is provided and the piston 11 is moved by a small amount by the force of the spring. Thus, the grease 13 sealed in the lower part of the piston 11 in the lubricating oil container 10 is discharged from the lubricating oil outlet 15 by the piston 11 which is moved by a small amount by the pressing mechanism 14, and the grease 13 is discharged from the lubricating oil outlet 15, which is screwed into the The lubricating oil is supplied to the bearing 3 via a lubricating oil guide pipe 8.

By the way, when replacing the grease, it is preferable to periodically discharge a predetermined amount of grease depending on the life of the grease as shown in FIG. 9A. However, in the conventional automatic refueling device, as shown in FIG. 9B, the gas is continuously discharged, and as time passes, the gas pressure or spring force decreases due to chemical changes, so the discharge amount decreases accordingly. The drawback was that it could not withstand long-term use. Also, since remote control was not possible, efficiency was low. Furthermore, grease is supplied even when the bearing is not rotating, which is very uneconomical.

[Purpose of the invention]

The purpose of the present invention is to be able to periodically discharge a predetermined amount of lubricating oil when needed, to be able to withstand long-term use, to be very economical, to improve efficiency, and to be able to be controlled remotely from the outside. The purpose is to provide automatic refueling ljN.

[Summary of the invention]

In order to achieve the above object, the present invention is characterized by the following configuration. In other words, I! A fixing piezoelectric element is provided on the opposite side of the piston's IIl immersion oil outlet in the lW4 oil container, and a main power piezoelectric element is placed between the fixing piezoelectric element and the piston so as to be in contact with the fixing piezoelectric element. A piston-pressing piezoelectric element is provided between the main power piezoelectric element and the piston so as to be in contact with the main power piezoelectric element and the piston, and by applying a predetermined voltage to each piezoelectric element, each piezoelectric It is characterized in that the piston is moved by a minute amount by a minute displacement generated in the element.

[Embodiments of the invention]

FIG. 1 is a sectional view showing the configuration of an embodiment of the present invention.

Note that the same parts as in FIG. 8 are given the same reference numerals, and detailed explanations will be omitted. In FIG. 1, reference numeral 20 denotes a pressing means for moving the piston 11 by a minute amount, and this pressing means 20
Ha, rIJ81! A fixing piezoelectric element 21 provided above the piston 11 inside the oil container 1°, and this fixing piezoelectric element 2
1 and the piston 11, the fixing piezoelectric element 2
a main power piezoelectric element 22 provided so as to be in contact with 1;
A piston-pressing piezoelectric element 23 is provided between the main power piezoelectric element 22 and the piston 11 so as to be in contact with each other.

Note that the grease 13 sealed in the lower part of the piston 11
The amount of encapsulation is designed so that it can be changed according to the application.

FIG. 2(a) shows the cross-sectional shapes of the fixing piezoelectric element 21 and the piston pressing piezoelectric element 23, and FIG.
) indicates the cross-sectional shape of the main power piezoelectric element 22. The fixing piezoelectric element 21 and the piston pressing piezoelectric element 23 are displaced in the diametrical direction when a predetermined voltage is applied,
It is fixed to the lubricating oil container 10. Further, the main power piezoelectric element 22 is displaced in the axial direction when a predetermined voltage is applied, and presses the piston-pressing piezoelectric element 23, which is free without the predetermined voltage applied, downward. There is.

Next, the characteristics of the piezoelectric elements (the fixing piezoelectric element 21, the main power piezoelectric element 22, and the piston pressing piezoelectric element 23) will be explained. The piezoelectric element described above is widely used as an actuator because minute displacement can be obtained by an electric signal and it is mechanically simple. That is, in FIG. 3, when a DC voltage is applied from a power source 32 between the poles of a piezoelectric element 31 made of ceramic such as lead zirconate titanate, the piezoelectric element 3
1 expands. This extension l, that is, the displacement amount λ is λ-d33V (2
It is expressed as In the above formula (2), d33 is the pressure constant, and ■ is the applied DC voltage.

FIG. 4 is a diagram showing the relationship between the DC voltage V and the displacement amount λ. As is clear from FIG. 4, the amount of displacement λ of the piezoelectric element body 31 is obtained in proportion to the magnitude of the DC voltage .

On the other hand, if it is desired to roughly increase the displacement amount λ, a plurality of piezoelectric elements 31 may be stacked. For example, if n pieces are laminated, the total displacement λD is expressed as λB=-nλ (3). Therefore, if the piezoelectric strain constant d33 is 450 x 10°" [m/V], By stacking a plurality of layers 31, a displacement of several μm can be easily obtained.

In reality, the piston 11 needs to be displaced in several layers depending on the size of the bearing. For example, 30g of grease must be added to a ball bearing with an inner diameter of 50mm, but in order to do so, I! If the inner diameter of lubricant container 10 is 1100a, piston 11 needs to be displaced by about 4 am. At this time, the piston 11 requires a pressure of about 10 mm/cm2 to compensate for the load, that is, the pressure loss of the lubricating oil passing through the lubricating oil nipple, lubricating oil guide pipe, and bearing.

Next, the operation of this device will be explained. First, a predetermined voltage is applied to the fixing piezoelectric element 21 and the fixing piezoelectric element 21 is fixed to the lubricating oil container 10 by being displaced in the diametrical direction. Next, a predetermined voltage is applied to the main power piezoelectric element 22 to displace it in the axial direction and press the piston pressing piezoelectric element 23 that is in contact with the main power piezoelectric element 22. Then,
The piston 11 in contact with the piston pressing piezoelectric element 23 moves a small amount, and this movement causes the piston 1
Grease 13 sealed in the lower part of lubricating oil discharge port 15 is discharged from lubricating oil discharge port 15 . Thereafter, a predetermined voltage is applied to the piston pressing piezoelectric element 23, and the voltage supply to the fixing piezoelectric element 21 and the main power piezoelectric element 22 is stopped. Then, the piston pressing piezoelectric element 23 is displaced in the diametrical direction and fixed to the lubricating oil container 10, and at the same time, the fixation of the fixing piezoelectric element 21 is released. As a result, the fixing piezoelectric element 21 moves toward the piston pressing piezoelectric element 23 together with the main power piezoelectric element 22.

This type of operation has good frequency characteristics, so
Switching is possible by using high-speed switching semiconductor elements. Therefore, by repeating the above operation several times, the piston 11 can be moved several times, and a predetermined amount of grease 13 required for one replenishment can be discharged to the bearing.

The magnitude of the voltage applied to each of the piezoelectric elements 21 to 23 may be the same voltage as that of the piezoelectric elements 21 to 23, but the magnitude of the voltage applied to each of the piezoelectric elements 21 to 23 may be the same,
In the case of 3, it is possible to use a small voltage necessary for fixing it to the lubricating oil container 10, and in the case of the main power piezoelectric element 22, it is also possible to increase the displacement λ by increasing the applied voltage . be.

However, quantitatively, the displacement amount λa of the main power piezoelectric element 22 in one energization cycle, that is, the movement amount of the piston 11, is determined as follows.

FIG. 15 is a diagram showing the relationship curve between the displacement amount λ of the piezoelectric element and the load F, and the relationship curve ■ between the displacement amount λ of the piezoelectric element and the load on the piston 11. As shown in Figure 5, each of the above curves L
The balance point P above 15 and 2 is determined as the displacement amount λa of the main power piezoelectric element 22. In this way, the displacement λa of the main power piezoelectric element 22 is slightly smaller than the displacement λ of the piezoelectric element, but this can be easily estimated from the initial installation condition, and depending on the number of times the above operation is repeated, Thus, a predetermined grease supply amount can be obtained linearly.

As described above, according to this embodiment, by controlling the switching of the voltage supplied to each piezoelectric element 21 to 23 and the switching frequency by remote control, a predetermined amount of grease can be periodically supplied to the bearing when necessary. I can do it. Therefore, the period of use can be extended, and it is much more economical than conventional methods, and efficiency can also be improved. Moreover, it is applicable to bearings of any size or rotation speed.

Note that the present invention is not limited to the above embodiments. For example, in the embodiment described above, the piezoelectric element 23 for pressing the piston was provided so as to be in contact with the piston 11, but the piezoelectric element 23 for pressing and fixing the piston may be formed integrally with the piston 11. Further, in the above embodiment, the case where the grease 13 is supplied to the bearing is shown, but it is also applicable to the case where m's oil other than grease is supplied. Note that the number of stacked piezoelectric elements 21 to 23 is arbitrary, and the size of the lubricating oil container 10 can also be changed arbitrarily. It goes without saying that various other modifications can be made without departing from the gist of the present invention.

〔Effect of the invention〕

According to the invention, ilI! A fixing piezoelectric element is provided on the opposite side of the l1llft oil discharge port of the piston in the oil container, and a fixing piezoelectric element is provided between the fixing piezoelectric element and the piston so as to be in contact with the fixing piezoelectric element. A piston-pressing piezoelectric element is provided so as to come into contact with the main power piezoelectric element and the piston, and by applying a predetermined voltage to each piezoelectric element, the piston is moved by a minute amount by a minute displacement generated in each piezoelectric element. Therefore, the automatic lubrication system is capable of periodically discharging a predetermined amount of lubricating oil when needed, can withstand long-term use, is very economical, improves efficiency, and can be remotely controlled from the outside. can be provided.

[Brief explanation of drawings]

1 to 6 are diagrams showing one embodiment of the present invention, in which FIG. 1 is a sectional view showing the configuration, FIGS. 2(a) and 2(b) are front sectional views of each piezoelectric element, and FIG. Figures 3 and 4 are explanatory diagrams of the operation of the piezoelectric element alone, Figure 5 is a diagram showing the relationship between the pressure-displacement curve and the load-displacement curve of the piezoelectric element, and Figure 6 is the number of operations of the piezoelectric element and the amount of grease supplied. FIG. 7th
Figures to Figures 9 are diagrams showing conventional examples. Figure 7 is a cross-sectional view showing the state in which a conventional automatic oil supply device is connected to a rotating machine, Figure 8 is a cross-sectional view showing the configuration, and Figure 9 is a diagram showing the relationship between time and time. It is a figure which shows the relationship of the amount of oil supply. 10...l)! Oil container, 11... Piston, 12.
0 ring, 13... Grease, 20... Pressing mechanism, 21... Piezoelectric element for fixing, 22... Piezoelectric element for main power, 23... Piezoelectric element for pressing piston, 31...
・Single piezoelectric element. Applicant's representative Patent attorney Takehiko Suzue Figure 1 Figure 2 (a) (b) Figure 4 Figure 5 Figure 7

Claims (2)

[Claims] (1) A piston provided in the lubricating oil container is pressed by a pressing means to move a small amount, and the movement of the piston causes the lubricating oil in the lubricating oil container to be discharged from the lubricating oil outlet. In the automatic oil supply device, the pressing means includes a fixing piezoelectric element provided in the lubricating oil container on a side opposite to the lubricating oil outlet of the piston, and a fixing piezoelectric element provided between the fixing piezoelectric element and the piston. a piezoelectric element for main power provided so as to be in contact with the piezoelectric element for main power, and a piezoelectric element for pressing the piston provided so as to be in contact with the piezoelectric element for main power and the piston between this piezoelectric element for main power and the piston. An automatic oil supply device comprising: an element; and means for moving the piston by a minute amount by slight displacement of each piezoelectric element caused by applying a predetermined voltage to each piezoelectric element. (2) The automatic oil supply device according to claim (1), wherein the piston utilizes a piston-pressing piezoelectric element.