JPS62148822A - Measuring instrument for thrust load on bearing - Google Patents

Abstract

PURPOSE:To measure a thrust load operating on a bearing speedily and accurately by providing cantilever type or both-end supported beam type load converting members which are arranged at almost equal intervals in the circumferential direction of a bearing support member and where a stain gauge is stuck. CONSTITUTION:A thrust load generated on a shaft 1 is transmitted as a distributed load from the shaft 1 to the bearing 2 to operated on the load point P of a load conversion member 9 through a flange 6 and a bolt 12, and transmitted from the strain inducing part 9a of the load conversion member 9 to a fixing bolt 10, and the load is further transmitted from the fixing bolt 10 to the bearing support member 8 and supported. The strain gauge 11 is displaced by the thrust load operating on the load conversion member 9 in the process of transmission of the thrust load and the displacement is converted into an electric signal proportional to the magnitude of the thrust load, so that the signal is led out through a lead line as the amount of information equivalent to an external force. Distributed loads operating on respective load conversion members 9 are detected from the led-out electric signal and the mean value is displayed and recorded as the thrust load.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a small and lightweight thrust load measuring device for accurately measuring the thrust load acting on a bearing.

[Prior Art] For example, when an excessive thrust load is applied to a bearing portion of a rotating machine such as an aircraft engine, a gas turbine, or an axial flow compressor, not only the bearing is damaged but also the entire machine is affected. Therefore, it is possible to prevent accidents and improve safety by measuring this thrust load and taking measures according to the value to bring the bearing to its original normal load state.

Therefore, various devices for measuring thrust loads have been studied.

[Problems to be solved by the invention] However, the area around the bearing is generally located in a narrow area,
Because the atmosphere is immersed in high-temperature oil, it is considered difficult to install a thrust load measuring device in this area, and the mechanism for detecting thrust load and the equipment equipped with this mechanism may become large. However, it is difficult to put it into practical use. Therefore, in the past, operations were carried out without a thrust load measuring device, double excuses were made during operation, and inspections of the degree of damage to bearings, etc. were determined based on guesswork and experience. The vehicle was operated in a sloppy manner, which was the biggest safety defect.

In view of the above-mentioned circumstances, the present invention has been made with the object of making it possible to quickly and accurately measure the thrust load acting on a bearing by installing a small and lightweight thrust load measuring device around the bearing. be.

Means for Solving Problems] The present invention provides a bearing support member disposed with a slight gap on the side of a flange fixed to the outer periphery of a bearing outer race fitted to a rotatable shaft; A cantilever-like or both-end supported beam-like load conversion member arranged at approximately equal intervals in the circumferential direction of the bearing support member and having strain gauges attached thereto, and a load conversion member that converts the thrust load acting on the bearing through the flange. A member for transmitting a load to the member, and a member attached to the bearing support member to support the tangential force due to the drag torque acting in the circumferential direction of the flange, and the thickness of the shaft in the axial direction is at least partially thinned. The structure includes a drag prevention fitting and a transmission member that transmits a tangential force due to a drag torque acting on the flange to the drag prevention fitting.

[Operation] Thrust load is transmitted from the shaft to the bearing, the flange of the bearing outer race, and the thrust load transmission member to the load conversion member, and by displacing the load conversion member, it is detected by the strain gauge and taken out to the outside. In addition, the tangential force due to the twisting torque that occurs as the shaft rotates is supported by the drag-preventing metal fitting.

[Example] Hereinafter, an example of the present invention will be described with reference to the accompanying drawings.

1 to 4 show a first embodiment of the present invention, in which an inner race 3 of a bearing 2 is fitted to a rotatable shaft 1 so as to be able to rotate integrally with the shaft 1, and the outer circumference of the inner race 3 is An outer race 5 is fitted through the balls 4, and a flange 6 is fixed to the outer periphery of the outer race 5. Also, the inner race 3 is tightened by the nut 7.
Fixed to 1.

A hollow cylindrical bearing support member 8 fixed to a casing (not shown) is disposed on the side of the flange 6 so that a required gap G1 is maintained between the bearing support member 8 and the flange 6. A plurality of load conversion members 9 arranged at approximately equal intervals in the circumferential direction are fixed in a cantilever shape by a plurality of fixing bolts 10 on the side opposite to the flange 6 of the load conversion members 9. Strain gauges 11 or 11' are attached to the upper and lower concave portions of the strain-generating portion 9a or to the inner surface of the circular hole portion as required.

A plurality of bolts 12 for thrust load transmission are installed at approximately equal intervals in the circumferential direction of the flange 6 so as to pass through the flange 6 in the longitudinal direction of the shaft 1. It penetrates through and its tip is fixed to the tip of the cantilever-shaped portion of the load converting member 9. The outer diameter of the bearing support member 8 of the bolt 12 is slightly smaller than the inner diameter of the through hole 13, and a gap G2 is maintained between the bolt 12 and the inner circumference of the through hole 13. 9
The diameter is larger than the outer diameter of the penetration part, and the step portions at both ends of the large diameter part abut on the side of the flange 6 and the side of the load conversion member 9, respectively,
When the bearing 2 receives a thrust load and the flange 6 deforms, the thrust load is not transmitted to the bearing support member 8 but is transmitted to the load conversion member 9 via the bolt 12.

A bolt 14 is installed in the circumferential direction of the flange 6 so as to be disposed between the load converting members 9°9 and to pass through the flange 6.The bolt 14 passes through the through hole 18 of the bearing support member 8, and The tip protrudes into a recess 15 provided in the bearing support member 8 . Further, both ends of the anti-tangling fitting 17 are fixed to the recess 15 by fixing bolts 16, and the tip of the bolt 14 is fixed to the center of the anti-tangling fitting 17. It is a centrally loaded beam with support at both ends. The outer diameter of the part where the bolt 14 passes through the bearing support member 8 is smaller than the inner diameter of the through hole 18.
A gap G3 is maintained between the inner periphery and the diameter is larger than the outer diameter of the penetration part of the flange 6 and the outer diameter of the penetration part of the anti-tangling fitting 17. When the bearing 2 receives a thrust load and the flange 6 deforms, the thrust load is not transmitted to the bearing support member 8 and is passed through the bolt 14 to the anti-slip fitting. 17. Also, the anti-tangling fitting 17 is attached to the shaft 1.
It has a thin plate structure where the thickness in the axial direction is at least partially thin, so that it can be easily displaced with an extremely small force when a thrust load shown in the Y direction in Fig. 1 is applied. The tensile and compressive stiffnesses are designed to be large against the tangential force due to the drag torque acting in the X direction.

The thrust load generated on the shaft 1 is transmitted from the shaft 1 to the bearing 2 as a distributed load, and from the bearing 2 to the flange 6 and the bolt 12.
It acts on the load point P of the load converting member 9 via the load converting member 9, is transmitted from the strain-generating portion 9a of the load converting member 9 to the fixing bolt 10, and is transmitted from the fixing bolt 10 to the bearing support member 8, where it is supported.

In the above-mentioned thrust load transmission process, the strain gauge 11 is displaced by the thrust load acting on the load conversion member 9, and this displacement is converted into an electric signal proportional to the magnitude of the thrust load and is transmitted by a lead wire to an electric signal equivalent to an external force. It is extracted as the amount of information. The distributed loads acting on each load conversion member 9 are detected from the extracted electrical signals, and the average value thereof is displayed and recorded as a thrust load.

If the thrust load acting on the shaft 1 is in the opposite direction, it is detected as a negative output. Since the gap G1 between the flange 6 and the bearing support member 8 is larger than the displacement of the load point P of the load conversion member 9, the flange 6 and the bearing support member 8 do not come into contact with each other due to the thrust load. There is no problem with measurement.

As the shaft 1 rotates, rotational torque is generated in the flange 6 of the bearing 2 in the X direction (tangential direction) in FIG. In this case, if there is no drag prevention fitting 17, the relative positions of the flange 6 and the bearing support member 8 in the circumferential direction will change,
The portion of the bolt 12 that passes through the bearing support member 8 may come into contact with the inner periphery of the through hole 13, increasing the frictional force between the bolt 12 and the through hole 13, and reducing the accuracy of thrust load measurement. However, in the present invention, the anti-entanglement fitting 17 is provided, and the anti-entanglement fitting 17 has a load direction along the tensile and compressive load axes in response to the tangential force due to the entangling torque, so that the tensile and compressive rigidity is reduced. This becomes a large value, and a reaction force that sufficiently opposes the tangential force is generated, making it possible to suppress the displacement in the tangential direction to a minute level. Further, the anti-dangle fitting 17 is displaced by an extremely small reaction force against a thrust load. Therefore, 90% or more of the thrust load is transmitted to the load conversion member 9.

5 to 8 show a second embodiment of the present invention. In the previous embodiment, the load conversion member 9 and the strain gauge 11 were installed outside the bearing support member 8, whereas in this embodiment, the load conversion member 9 and the strain gauge 11 were installed outside the bearing support member 8. A recess 19 is provided in the bearing support member 8, and a strain gauge 11 is installed in the recess 19.
The load conversion member 9 to which the
It is sealed by In the figure, 21 is a bolt that fixes N20 to the bearing support member 8. With such a configuration, it is possible to protect the load conversion member 9 and the strain gauge 11 from direct attack by lubricating oil and mist.

FIGS. 9 and 10 show a third embodiment of the present invention, and the first embodiment shown in FIG.
In the second embodiment, the load conversion member 9 was in the form of a cantilever beam, whereas in the present example, the load conversion member 9 is in the form of a beam supported at both ends, so that a concentrated load acts on the instep. . With such a configuration, it is possible to detect a thrust load larger than that in the first and second embodiments, and it is possible to detect twice as much load.

11 and 12 show a fourth embodiment of the present invention, in which the load conversion member 9 is shaped like a beam supporting both ends, and the bearing support part vJ8
A recess 19 is provided in the recess 19, and a load converting member 9 in the form of a support beam at both ends with strain gauges 11 attached thereto is accommodated, and the recess 19 is sealed with M2O.

With such a configuration, it becomes possible to measure large thrust loads, and the load conversion member 9 and the strain gauge 1
1 from direct attack by the lubricating oil mist.

Components in FIGS. 5 to 12 that are the same as those shown in FIGS. 1 to 4 are given the same reference numerals.

It should be noted that the present invention is not limited to the above-described embodiments, and it goes without saying that various changes can be made without departing from the gist of the present invention.

[Effects of the Invention] According to the bearing thrust load measuring device of the present invention, <I) No matter whether the thrust load is a repetitive force due to immersion in high-temperature oil, vibration, sudden load, or sudden release, the load converting member Because the load is transmitted quickly and reliably, highly accurate load detection is possible.<n> The load conversion member is attached to the bearing support member, and no special member is required to install the load conversion member, so the device The whole becomes smaller and lighter1.
<[1] To prevent abnormal loads from being applied to the bearing, it is possible to maintain it in a normal state during the assembly stage.
The safety of the equipment can be improved; ■ Damage to the bearing section is prevented, the burden on other mechanical parts is reduced, and other abnormalities can be detected early by stabilizing the area around the bearing. <V
＞ The load conversion member with strain gauges attached can be used repeatedly and is interchangeable, so it is easy to manufacture. Various excellent effects can be achieved, such as easy inspection of parts and easy replacement of load conversion members.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram of the first embodiment of the bearing thrust load measuring device of the present invention, Fig. 2 is a view taken in the ■-n direction of Fig. 1, and Fig. 3 is a view taken in the -■ direction of Fig. 2. Arrow view, Figure 4 is I of Figure 2
FIG. 5 is an explanatory view of the second embodiment of the bearing thrust load measuring device of the present invention, FIG. 6 is a view taken in the Vl-V1 direction of FIG. 5, and FIG. Fig. 6 is a view in the ■-v■ direction of Fig. 6, Fig. 8 is a view in the -v direction of Fig. 6, and Fig. 9 is an explanatory diagram of the third embodiment of the bearing thrust load measuring device of the present invention. , FIG. 10 is a view taken along the direction of arrows X-X in FIG. 9, and FIG.
The figure is an explanatory diagram of a fourth embodiment of the bearing thrust load measuring device of the present invention, and FIG. 12 is a view taken in the direction of Xl[-Xl[ of FIG. 11]. In the figure, 1 is a shaft, 2 is a bearing, 6 is a flange, 8 is a bearing support member, 9 is a load conversion member, 11.11' is a strain gauge, 13
is a through hole, 14 is a bolt, 17 is an anti-tangling fitting,
18 indicates a through hole.

Claims (1)

[Claims] 1) A bearing support member disposed at a slight gap on the side of a flange fixed to the outer periphery of a bearing outer race fitted to a rotatable shaft, and approximately equally spaced in the circumferential direction of the bearing support member. a load converting member in the form of a cantilever beam or a beam supported at both ends, which is arranged with a strain gauge attached thereto; a load transmitting member that transmits the thrust load acting on the bearing to the load converting member via the flange; and the flange. a drag prevention fitting that is attached to the bearing support member and has at least partially reduced thickness in the axial direction of the shaft to support the tangential force due to the drag torque acting in the circumferential direction of the shaft; A thrust load measuring device for a bearing, characterized in that it is provided with a transmission member that transmits tangential force due to circumferential torque to a tangling prevention fitting.