CN111386394B

CN111386394B - Liquid storage structure

Info

Publication number: CN111386394B
Application number: CN201880076135.2A
Authority: CN
Inventors: 平野秀一
Original assignee: Isuzu Motors Ltd
Current assignee: Isuzu Motors Ltd
Priority date: 2017-11-27
Filing date: 2018-11-22
Publication date: 2022-01-07
Anticipated expiration: 2038-11-22
Also published as: CN111386394A; JP6928215B2; JP2019094868A; PH12020550681A1; WO2019103096A1

Abstract

A liquid storage structure includes a liquid storage portion for storing liquid, an excitation source, and a baffle. The baffle plate has a lower surface including a recess opening downward, and a space defined by the liquid surface and the recess is formed when the liquid surface reaches the lower surface as the liquid surface level in the liquid storage portion rises. The recess is shaped so that the natural frequency of the liquid on the excited side, including the liquid reservoir and the inside of the liquid reservoir, does not coincide with the natural frequency of the excitation source.

Description

Liquid storage structure

Technical Field

The present disclosure relates to a liquid storage structure, and more particularly, to a technique for providing a baffle plate on an oil pan for storing engine oil.

Background

Generally, an oil pan for storing engine oil is provided at a lower portion of a cylinder block of an engine. The oil stored in the oil pan is pumped by an oil pump driven by the power of the engine, supplied to each sliding element of the engine, and then circulated to the oil pan (see, for example, patent document 1).

Prior art documents

Patent document

Patent document 1: japanese unexamined patent publication No. Hei 11-280547

Disclosure of Invention

Problems to be solved by the invention

However, as oil is sucked from the oil pump, vibration is transmitted to the oil pan and the engine oil stored in the oil pan. Therefore, when the natural frequency of an excitation source such as an oil pump matches the natural frequency of the excited side including the oil pan and the oil in the oil pan, noise may be generated due to these resonances. Such noise gives a driver or the like a sense of discomfort, and it is therefore desirable to effectively suppress the generation of noise.

The disclosed technology relates to a liquid storage structure that effectively suppresses the generation of noise.

Means for solving the problems

The disclosed technology is a liquid storage structure including: a liquid storage unit that stores liquid; an excitation source that applies vibration to the liquid storage unit and the liquid in the liquid storage unit; and a baffle. The lower surface of the baffle plate is opposite to the liquid surface of the liquid stored in the liquid storage part; the lower surface of the baffle plate includes a recess opening downward; when the liquid surface reaches the lower surface as the liquid surface level in the liquid reservoir portion rises, a space defined by the liquid surface and the concave portion is formed. The recess is shaped so that the natural frequency of the liquid on the excited side, including the liquid reservoir and the inside of the liquid reservoir, does not coincide with the natural frequency of the excitation source.

In the liquid storage structure, the shape of the concave portion may be set so that the natural vibration characteristic on the excited side is a frequency characteristic having maximum values of amplitudes in two frequency bands different from the natural vibration frequency of the excitation source due to the influence of the resonance frequency of the closed space.

In the liquid storage structure, the baffle plate may be provided with a through hole communicating with the recess and discharging air from the closed space, when any one of the maximum values coincides with the natural frequency of the excitation source, in accordance with the frequency characteristic on the excited side having maximum values of amplitude in two frequency bands due to the influence of the resonance frequency of the closed space.

In the above-described liquid storage structure, the concave portion may be formed by being defined by a plurality of reinforcing ribs provided on the lower surface of the baffle plate.

In the above-described liquid storage structure, the liquid storage portion may be an oil pan provided at a lower portion of the engine, the liquid may be oil stored in the oil pan, and the excitation source may be an oil pump that pumps the oil.

Effects of the invention

The technology according to the present disclosure relates to a liquid storage structure that can effectively suppress the generation of noise.

Drawings

Fig. 1 is a schematic view showing a liquid storage structure according to the present embodiment.

Fig. 2A is a schematic perspective view of the baffle of the present embodiment viewed obliquely from below.

Fig. 2B is a schematic perspective view of the baffle of the present embodiment as viewed obliquely from below.

Fig. 3 is a schematic diagram illustrating the natural vibration characteristics of the excited side of the liquid storage structure according to the present embodiment.

Fig. 4 is a schematic view showing a liquid storage structure according to another embodiment.

Fig. 5 is a schematic diagram illustrating the natural vibration characteristics of the excited side of the liquid storage structure according to another embodiment.

Detailed Description

Hereinafter, the liquid storage structure of the present embodiment will be described with reference to the drawings. The same components are denoted by the same reference numerals, and their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

Fig. 1 is a schematic diagram showing a liquid storage structure 1 of the present embodiment. The liquid reservoir structure 1 is a reservoir structure of oil that lubricates each sliding element of the engine E, for example, and includes an oil pan 10 and a baffle 20 fixed to a lower portion of a cylinder block (crankcase) CB.

The organic oil O is stored in the oil pan 10. An oil filter 11 for removing foreign matter contained in the oil O is immersed in the oil O in the oil pan 10. An oil pump 13 for pumping oil O is connected to the oil strainer 11 via a suction pipe 12.

The oil pump 13 is an example of an excitation source for giving vibration to the oil pan 10 and the oil O stored in the oil pan 10, and is driven by power taken out from a crankshaft, not shown, of the engine E, for example. The oil O pumped from the oil pan 10 by the driving of the oil pump 13 is supplied to each sliding element such as a valve mechanism, not shown, of the engine E, and then is circulated to the oil pan 10 through a return pipe, not shown.

The baffle 20 is a plate member that ensures the stability and rigidity of the liquid surface of the oil O stored in the oil pan 10, for example, and the peripheral edge portion thereof is fixed to the inner wall of the oil pan 10 or other portions of the engine E. Further, a plurality of concave portions 21 are formed in the lower surface of the baffle 10 facing the liquid surface L of the oil O.

Specifically, as shown in fig. 2A, the recess 21 is defined by a peripheral reinforcing rib 22 and a plurality of (2 in the illustrated example) inclined reinforcing ribs 23, the peripheral reinforcing rib 22 being formed in a substantially rectangular shape along the peripheral edge of the lower surface of the baffle plate 20, and the inclined reinforcing ribs 23 being provided so as to extend diagonally inside the peripheral reinforcing rib 22 and intersect with each other. As shown in fig. 2B, the concave portion 21 may be defined by a peripheral reinforcing rib 22 and a plurality of grid-like reinforcing ribs 24 provided in a grid-like manner in the peripheral reinforcing rib 22.

As shown in fig. 1, when the liquid surface L of the oil O rises according to the driving state of the oil pump 13 and reaches the lower surface of the baffle plate 20, the plurality of concave portions 21 form a sealed space S that seals air by the liquid surface L and the concave portions 21. That is, the baffle 20 is configured not to have a through hole or the like that communicates the lower surface with the upper surface or the side surface of the baffle 20 at least in the range where the recess 21 is formed.

When vibration is transmitted to the oil pan 10 and the oil O in the oil pan 10 due to oil suction by the oil pump 13, resonance may occur because the natural frequency of the oil pump 13 (hereinafter referred to as an excitation source) coincides with the natural frequency of the oil O in the oil pan 10 and the oil O in the oil pan 10 (hereinafter referred to as an excited side).

In the present embodiment, in order to prevent such resonance, values such as the spatial volume and the opening area of the recess 21 are set so that the natural vibration characteristic on the excited side changes from a characteristic line L1 having only one peak of amplitude, which is shown by a broken line in fig. 3, to a characteristic line L2 having maximum values P1 and P2 of amplitude in 2 different frequency bands, which are shown by a solid line, due to the influence of the resonance frequency of the closed space S. These numerical values such as the space volume and the opening area are not uniquely determined, and may be set appropriately by experiments according to the specification of the engine E, the capacity of the oil pump 13, the shape of the oil pan 10, and the like.

When the natural vibration characteristics of the excited side are changed in this manner, the natural vibration frequency of the excited side does not match the natural vibration frequency of the excitation source, and resonance of the natural vibration frequency and the natural vibration frequency is reliably prevented, whereby generation of noise, damage, and the like due to resonance can be effectively suppressed.

The present invention is not limited to the above-described embodiments, and can be implemented by being appropriately modified within a range not departing from the gist of the present invention.

For example, when the frequency characteristics on the excited side have maximum values P1 and P2 of amplitude in 2 different frequency bands due to the influence of the resonance frequency of the closed space S, and either one of these maximum values P1 and P2 matches the natural frequency of the excitation source, it is preferable that the baffle 20 be provided with through holes 25 that communicate with the recessed portions 21 and discharge the air in the closed space S, as shown in fig. 4. With this configuration, the characteristic of the excited natural vibration changes from the characteristic line L3 shown by the broken line in fig. 5 and having 2 maximum values P1 and P2 in amplitude to the characteristic line L4 shown by the solid line and having only one peak in amplitude, and the occurrence of noise due to resonance, breakage, and the like can be effectively prevented.

In the above embodiment, the case where the recess 21 is defined by the

reinforcing ribs

22, 23, and 24 to form a plurality of recesses has been described, but the number of the recesses 21 may be only 1, and may be defined by other projections or the like other than the reinforcing ribs.

The liquid storage structure 1 of the above embodiment has been described by taking the oil pan 10 of the engine E as an example, but can be widely applied to other liquid storage structures such as an oil pan of a transmission and a fuel tank.

The present application is based on the japanese patent application filed on 27/11/2017 (japanese application 2017-.

Industrial applicability

The invention relates to a liquid storage structure which can effectively inhibit the generation of noise.

Description of the reference numerals

1 liquid storage structure

10 oil pan

11 oil filter

12 suction pipe

13 oil pump

20 baffle

21 concave part

22 peripheral reinforcing rib

23 inclined stiffener

24 grid-shaped reinforcing rib

25 through hole

Claims

1. A liquid storage construction comprising:

a liquid storage part for storing liquid,

an excitation source that imparts vibration to the liquid storage section and the liquid in the liquid storage section, and

a baffle plate;

the lower surface of the baffle plate is opposite to the liquid surface of the liquid stored in the liquid storage part;

the lower surface of the baffle plate includes a recess opening downward;

forming a closed space defined by the liquid surface and the concave portion when the liquid surface reaches the lower surface as the liquid surface level in the liquid storage portion rises;

the recess is shaped so that the natural frequency of the liquid on the excited side, including the liquid reservoir and the inside of the liquid reservoir, does not coincide with the natural frequency of the excitation source.

2. The liquid storage construction as claimed in claim 1, wherein

The shape of the recess is set so that the natural vibration characteristic on the excited side is a frequency characteristic having maximum values of amplitudes in two frequency bands different from the natural vibration frequency of the excitation source due to the influence of the resonance frequency of the closed space.

3. The liquid storage construction as claimed in claim 1, wherein

The recess is formed by being defined by the lower surface of the baffle plate and a plurality of reinforcing ribs provided to the lower surface of the baffle plate;

the baffle plate does not allow a lower surface of the baffle plate to communicate with an upper surface of the baffle plate at least in a range where the recess is formed, and a closed space is formed by the liquid surface and the recess.

4. The liquid storage construction as claimed in claim 2, wherein

5. The liquid storage construction as claimed in claim 1, wherein

The baffle plate is provided with a through hole which communicates with the recess and discharges air from the closed space.

6. A liquid storage construction as claimed in any one of claims 1 to 5, wherein

The liquid storage portion is an oil pan provided at a lower portion of the engine, the liquid is engine oil stored in the oil pan, and the excitation source is an oil pump that pumps the engine oil.