JPS58152929A - Bearing supporting device - Google Patents

Abstract

PURPOSE:To prevent damage of a bearing and destruction of a concrete wall, by flowing a coolant in radial and peripheral stays to decrease thermal elongation and thrust force of the radial stays in the radial direction. CONSTITUTION:A bracket disc 4a holding a bearing 2, radial stays 9 of hollow section radially protruded from this disc 4a to the outside and fixedly propped with the outside end to a concrete wall 8 through a base 7, and peripheral stays 10 of hollow section connecting the outside ends of these stays 9 are provided to flow a coolant in a coolant passage formed by mutually penetrating these stays 9 and both ends of the stays 10.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a bearing support device, and particularly to a bearing support device suitable for supporting a guide bearing (hereinafter referred to as a bearing) of a water turbine generator or the like.

In recent years, there has been a significant difference in electricity demand in Japan between day and night, and hydroelectric power generation facilities have been increasing in capacity in order to supply peak electricity and make effective use of surplus electricity at night. These large-capacity pumped storage power generation facilities are becoming faster in order to improve economic efficiency, and the conventional 3
In contrast to the 00 rpm class, recently a 700 rpm class is being planned. As machines become faster, problems that have never been seen before arise. One example of this is the failure of the concrete wall due to thermal expansion of the bearing support device and the bearing burnout due to the reduction of the bearing gap, which is the motivation for the present invention.

1 and 2 show a conventional example of a bearing support device. A bearing 2 arranged around the rotating shaft 1 is housed in a bearing support frame 3, and the bearing support frame 3 is further fitted with a bracket disc 4.
It is attached to the inside of a.

The bracket 4 having the bracket disc 4ae consists of a bracket, a disc 4a, and a radially protruding bracket arm 4b.A vibration isolation stay 5 is attached to the tip of the bracket arm 4b, and the surrounding concrete IJ-to-wall 8
It is tensioned and fixed via a leaf spring 6 to a pace 7 placed in the. The lateral rigidity of the bracket 4 with respect to the bending natural frequency of the rotating shaft 1 is determined by the plate spring 6'-! The radial strength of the composite material under radial compression is approximately determined by the radial strength of the composite material (denoted hereafter by k). However, such a bearing support device has the following drawbacks regarding the safety of the concrete wall 8 and the maintenance of the bearing gap, and is an obstacle to increasing the speed of the machine.

In the conventional device, a radial tensile force FB is generated in the concrete wall 8 due to thermal expansion of the bracket arm 4b during operation. This tensile force FR is determined by the above-mentioned radial synthetic agent k.
is proportional to. On the other hand, in order to increase the speed of the machine, it is necessary to increase the natural bending frequency of the rotary shaft 1, that is, to increase the synthetic material k. Therefore, as the speed of the machine increases, the radial tensile force FR of the concrete wall 8 inevitably increases. This tensile force FR will be supported by the concrete wall 8, but in the structure in which the bracket 4 is placed on the top of the machine (see Figure 1), the concrete wall 8 cannot be made unnecessarily thick due to the structure, so a large tensile force FR will be supported. FR cannot be absorbed, resulting in destruction of the concrete wall 8. On the other hand, in a structure (not shown) in which the bracket 4 is placed at the bottom of the machine, the tensile force FR is supported by a sufficiently strong concrete wall 8 or concrete foundation, but in this case, the plug/soto arm 4b The bearing 2 is conversely pushed inward by the elongation due to thermal expansion (hereinafter referred to as thermal elongation). When the diameter of the concrete foundation is large, that is, when the length of the bracket arm 4b is large, the amount of thermal expansion is also large, and the amount of thermal expansion far exceeds the required bearing clearance amount. Therefore, metal contact occurs between the surface of the bearing 2 and the surface of the rotating shaft 10, causing bearing burnout. As described above, the conventional bearing support device has the disadvantage that the concrete wall 8 is destroyed due to thermal expansion and the bearing 1 is easily burnt out due to metal contact due to a reduction in the bearing gap.

The present invention has been made in view of the above points, and its object is to provide a bearing support device that prevents bearing burnout and concrete wall destruction.

That is, the present invention includes: a bracket disk holding a guide bearing; a radius stay projecting radially outward from the bracket disk and having a hollow cross section whose outer end is fixed to a concrete wall through a pace; A peripheral stay having a hollow cross section is provided connecting the outer ends of these radius stays, and the refrigerant is made to flow through a refrigerant passage formed by mutually penetrating both ends of the radius stay and the peripheral stay. It is something to do.

The present invention will be explained below based on the illustrated embodiments. An embodiment of the present invention is shown in FIGS. 3-6.

Note that parts that are the same as those in the conventional model are given the same reference numerals, and therefore their explanations will be omitted. In this embodiment, there is a bracket disc 4a that holds the bearing 2, and a bracket disc 4a that protrudes radially outward, and its outer end is connected to a concrete wall 8 through a pace 7.
a radius stay 9 having a hollow cross section fixed to the radius stay 9;
A circumferential stay 10 having a hollow cross section is provided which connects the outer ends of these radius stays 9, and both ends of these radius stays 9 and circumferential stays 10 are formed so as to penetrate through each other.
, I turned on the refrigerant to flow the refrigerant into the refrigerant passage. In other words, the radius stay 9 and the circumferential stay 10 form a series refrigerant passage (see Fig. 5) or a parallel refrigerant passage (see Fig. 6), and the refrigerant passes through the radius stay 9 and the circumferential stay 10, which are the refrigerant passages. were made to flow in series or in parallel as indicated by the arrows in the figure. In the same figure, 11
is a flow stop. By doing this, the radius stay 9 is cooled by the refrigerant, and the amount of thermal expansion of the radius stay 9 in the radial direction during operation is relaxed and small, and becomes less than the required bearing clearance amount. Since the bearing 2 is no longer pushed inward by the thermal elongation of step 9, it is possible to prevent the bearing 2 from being burnt out. Furthermore, since the amount of thermal expansion of the radial stay 9 is reduced, the tensile force Fi in the radial direction of the concrete wall 8 is also alleviated, and destruction of the concrete wall 8 can be prevented. Furthermore, the lateral rigidity of the entire bearing support device can be increased as can be expressed by the following equation, since the bending rigidity of the radius stay 9 can be increased by the longitudinal rigidity of the circumferential stay 10.

If the radial rigidity eKr of the radius stay 9, the bending rigidity iK of the radius stay 9, and the number of radius stays 9 is n, and the bearing support frame 3 is a rigid body, then the lateral rigidity of the entire bearing support device is:
is given by K,=n/2 (in K,+). In this way, the radial stiffness Kr4 bending stiffness of the radius stay 9,
Both will contribute to the size of the lateral stiffness K, so
As described below, the lateral rigidity is greater than that of the known structural example. That is, radius stays 13 are made to protrude radially from the bearing support frame 12 shown in FIG. 7 to the concrete wall 8,
In a known device in which both ends of the radius stay 13 are fixed to the bearing support frame 12 and the concrete wall 8, the radius stay 13
The radial stiffness Kr of 3 is the bending stiffness K.

Since it is extremely large compared to , the lateral stiffness of the entire device is K.

is given by - to Ki=n/2. That is, since the bending rigidity of the radius stay 13 does not contribute to the magnitude of the lateral rigidity Kt, the lateral rigidity is small accordingly. A so-called type steel is used for the radius stay 13 shown in FIGS. 8 and 9, and the concrete IJ-to wall 8 is supported by a sliding support device 14, as shown in FIG. 10. The radius stay 13 is replaced with a single disc-shaped bracket 15, and the concrete wall 8 is supported by a sliding support device 14 in the same way as the concrete wall 8. The radius stay 13 shown in FIG. In these known examples of devices, such as one in which the radial stays 13 are supported by circumferential stays 16, and the concrete wall 8 is also supported by a sliding support device 14, the sliding support device 14 Since it is supported on the concrete wall 8, the radius stay 13 (or disc-shaped bracket 15)
The radial stiffness Kr of is almost zero and is significantly smaller than the bending stiffness, so the lateral stiffness of the entire device is KL
−n/2 K, given by That is, radius stay 1
3 (or the disc-shaped bracket 15) does not contribute to the lateral rigidity of the entire device, so the lateral rigidity is small accordingly.

Note that as the refrigerant, a liquid or gas whose temperature is appropriately controlled is used, but in an environment where the water temperature of the dam is constant, it is economical to use dam water.

Another embodiment of the invention is shown in FIGS. 12 and 13. In this embodiment, the stay 10 having a radius of 9° and a circumferential stay 10 is assembled into a three-dimensional toroidal shape. In this case, since it is assembled into a three-dimensional torus shape, it can also be used as a bracket, making it unnecessary to install a bracket.

As described above, in the present invention, since the refrigerant is made to flow through the radius stay and the peripheral stay, the radius stay is cooled by the refrigerant, and the amount of thermal expansion and thrust tension in the radial direction of the radius stay is alleviated. This makes it possible to prevent burning of the bearing and destruction of the concrete wall, thereby providing a bearing support device that prevents the burning of the bearing and the destruction of the concrete wall.

[Brief explanation of the drawing]

Fig. 1 is a vertical sectional side view of a generator surrounding a bearing of a conventional bearing support device, Fig. 2 is a sectional view taken along line A-A in Fig. 1, and Fig. 3
The figures are a vertical sectional side view of the bearing surroundings of an embodiment of the bearing support device of the present invention, FIG. 4 is a sectional view taken along the line B-B in FIG.
The figure is a plan view showing a refrigerant passage of one embodiment of the bearing support device of the present invention, FIG. 6 is a plan view showing a refrigerant passage of the same embodiment, and FIG. A plan view, FIG. 8 is a plan view of another example, and FIG. 9 is a plan view of another example.
10 is a plan view of still another example of the conventional bearing support device, FIG. 11 is a plan view of still another example, and FIG. 12 is a plan view of the bearing support device of the present invention. A plan view of another embodiment, FIG. 13, is a sectional view taken along line C-Q in FIG. 12. 1... Guide bearing, 4a... Bracket disc, 9...
・Radius stay, 10...peripheral stay. Kudzu 8m 15”I) tt figure

Claims (1)

[Scope of Claims] 1. A bracket disk holding a guide bearing, and a radius stay having a hollow cross section that projects radially outward from the bracket disk and whose outer end is fixed to a concrete wall through a pace. , a circumferential stay having a hollow cross section is provided which connects the outer ends of these radius stays, and the refrigerant is made to flow through a refrigerant passage formed by penetrating both ends of these radius stays and the circumferential stays. bearing support device. 2. The bearing support device according to claim 1, wherein the radius stay and the circumferential stay are combined into a three-dimensional torus shape. 3. The bearing support device according to claim 1, wherein the refrigerant passage is a series or parallel refrigerant passage. 4. The bearing support device according to claim 1, wherein the refrigerant is water led from a dam. 5. The bearing support device according to claim 1, wherein the refrigerant is a liquid or gas adjusted to a constant temperature.