JPH0223884Y2 - - Google Patents

Description

[Detailed description of the invention] This invention is a flywheel device, particularly a flywheel device configured to convert electrical energy into inertial energy of a rotating body, store it, and then convert it back to electrical energy and supply it when necessary. This is related to the improvement of.

Conventionally, there has been a device of this type as shown in FIG.

1 is a foundation made of reinforced concrete, 2 is a generator pit formed in this foundation, 3 is a flywheel pit formed below it, 4 is a ventilation duct that connects the two pits, and 5 is the generator The generator is installed in the pit 2 and is configured as follows. That is, 6 is a stator, 7 is a stator frame that supports the stator, 8 is an air cooler attached to this frame, 9 is a bracket, and 10
1 is an upper rotating shaft, 11 is a main rotating shaft connected to the upper rotating shaft, 12 is a rotor attached to the main rotating shaft, 1
Reference numeral 3 denotes a flywheel connected to the lower part of the main rotating shaft, and is constructed by overlapping four discs 14 of appropriate thickness and joining them together with bolts 15. 1
6 is a thrust collar attached to the lower part of the flywheel, 17 is a thrust bearing, 18 is a lower bracket, 19A and 19B are blowers provided at the entrance of ventilation duct 4, and 20A and 20B are provided at the upper part of bracket 9. Another blower.

The conventional flywheel device is configured as described above, and the disk 14 that constitutes the flywheel is
As shown in Fig. 2, ordinary bolts 15 having a circular cross section with a constant thickness in the longitudinal direction were used as bolts for joining the This is a bush that is attached to the bolt hole 14C of the disc 14 for the purpose of fixing the disc 15.

Therefore, even if the heat spread of each disk tends to be different due to the difference in temperature rise of each disk of the flywheel, the bolts 15 have a uniform thickness in the longitudinal direction, and each disk has a uniform thickness. Since the relative movement is restrained, the radial bending stress on the bolt 15 becomes extremely large in some cases, which is a drawback.

This invention was devised to eliminate these drawbacks, and is characterized by a cross section in which the section modulus between the bushings of the bolt that connects the discs of the flywheel is smaller than that of the bushings. It is something to do.

An embodiment of this invention shown in FIGS. 3 and 4 will be described below.

Figure 3 shows the structure of the tightening bolts that constitute the main part of this invention, and shows each disc 14A, 14B.
The section between the bushes 21A and 21B of the tightening bolt 15 that is inserted through the bushes 21A and 21B, for example, the C section or the D section, has a cross section such that its section modulus is smaller than that of the bushes 21A and 21B. The cross section taken from the line in Figure 3-- is shaped as shown in Figure 4, and when a radial restraining force is applied, the above C
It is designed to be able to bend flexibly at the part or D part.

Note that 21A and 21B in FIG. 3 are bushes for fixing the tightening bolts.

In such a configuration, disks 14A and 14
Assuming that there is a difference in temperature rise between B and a relative deviation δ between the two, the bending moment M applied to the tightening bolt 15 due to this deviation δ is: M=6EIδ/l ₂ (where E: Young's modulus of the material, I: second moment of area of the bolt, l: span shown in Figure 3). If the relative deviation δ is large, the above-mentioned bending moment M will also be large, and a large bending stress will act on the tightening bolt. However, if the part where a large bending moment acts, that is, the part C in Fig. 3, is shaped as shown in Fig. 4, the second moment of inertia in the radial direction becomes small, so the bending moment M becomes small, and the bending of the tightening bolt is reduced. It is something that can relieve stress.

In addition, as shown in Fig. 3, not only the C part but also
Further effects can be obtained if the other portion (portion D) is also configured in a similar manner.

This invention is constructed as described above, and the tightening bolt that connects the discs of the flywheel has a cross section where the section modulus between the bushings is smaller than that of the bushing part, so that it is easy to bend flexibly at that part. As a result, the bending stress in the radial direction of the tightening bolt can be effectively alleviated.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view showing the configuration of a conventional flywheel device, Fig. 2 is a schematic diagram showing the shape of a tightening bolt for connecting the flywheel in the conventional device, and Fig. 3 is an example of an embodiment of this invention. A schematic diagram showing the shape of the tightening bolt in Fig. 3.
A sectional view taken at - in the figure is shown. In the figure, 5 is a generator, 13 is a flywheel, 1
4 is a disk of the flywheel, 15 is a tightening bolt, and 21A, 21B are bushes. Note that the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims for Utility Model Registration] (1) In a flywheel device that converts electrical energy into inertial energy of a rotating body and stores it, a fastening method in which multiple discs are overlapped and each disc is inserted through a bushing. 1. A flywheel device, wherein the flywheel is integrally connected by bolts, and the tightening bolt has a cross section such that a section modulus between the bushes is smaller than that of the bush portion. (2) The flywheel device according to claim 1, wherein the portions having a reduced section modulus are formed at at least two locations on the tightening bolt.