JPH0560161A - Rotary damper - Google Patents

Abstract

PURPOSE:To improve the machinability and simplify the structure of a rotary damper CONSTITUTION:A vane 3 and a sliding shaft 1, whose diameters are different from each other, are fitted to each other, and side plates 4 and 5 are fitted to both end of a casing 2 and tightened by bolts 6. An oil retaining chamber 18 and each of oil chambers 7 to 10 are communicated through the passage 20 extending from the hollow part 1A formed on the sliding shaft 1 to each of the oil chambers 7 to 10 penetrating the vane 3 in the direction to cross the vane 3 in parallel with the sliding shaft 1, and a check valve 21 is provided in the opening of the passage 20 of the vane 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a rotary damper that damps a swinging motion.

[0002]

2. Description of the Related Art A rotary damper has, for example, a vane whose base end is supported by a swing shaft, accommodated inside a cylindrical casing, a vane, a partition wall provided inside the casing, and side plates located at both ends of the vane. Defines a plurality of oil chambers inside the casing.

When the swing shaft swings, these oil chambers expand and contract, and the working oil in the shrinking oil chamber flows into the expanding oil chamber through the gap between the vane and the casing and the gap between the vane and the side plate. Then, the flow resistance at that time generates a damping force to damp the swing of the swing shaft.

The oil chambers that expand and contract at the same time communicate with each other via a passage formed in one side plate. Also,
A passage provided with a check valve is formed in the side plate to supply the hydraulic oil in the oil reservoir to the oil chamber where the oil amount is insufficient.

[0005]

By the way, in the case of such a rotary damper, the swing shaft and the vane are machined from the same member having a large diameter, and it is necessary to form a passage also in the side plate. As a result, it is difficult to process each member and the manufacturing cost is high.

The present invention has been made in view of the above problems, and an object thereof is to improve the workability of the rotary damper and to simplify the structure.

[0007]

SUMMARY OF THE INVENTION According to the present invention, a vane is provided at a symmetrical position of a swing shaft concentrically arranged inside a cylindrical casing, and a partition wall is formed at a symmetrical position of an inner circumference of the casing. And the partition walls and the side plates located at both ends of the vane define four oil chambers inside the casing,
An oil sump chamber that generates a damping force for the swing of the swing shaft due to the flow resistance of the hydraulic oil that flows between these oil chambers via the vane sliding gap, and that also compensates for fluctuations in the amount of oil in these oil chambers. In a rotary damper equipped with a check valve for guiding the working oil in the oil reservoir to each oil chamber, the vane and the swing shaft are coupled by different diameter fitting, and the side plates are fastened to both ends of the casing with bolts. , The oil reservoir chamber and the oil chambers are communicated with each other through a hollow portion formed in the swing shaft and a passage extending from the hollow portion in the transverse direction through the swing shaft and the vane to reach the oil chambers, The check valves are provided at the openings of these passages in the vane.

[0008]

Since the vane, the swing shaft, the casing, and the side plate are formed as independent members, it is possible to easily process each member and select a material for each member. Further, since the oil reservoir and the oil chambers are communicated with each other without the side plate, the side plate can be easily processed.

[0009]

1 and 2 show an embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes a swing shaft that concentrically passes through a cylindrical casing 2 having both ends opened, and a vane 3 is spline-coupled to the outer circumference of the swing shaft 1.

The vane 3 comprises an annular cross section 3A covering the outside of the swing shaft 1 and a vane section 3B provided at a symmetrical position on the outer circumference of the annular cross section 3A. The vane portions 3B have their tips slidably contacting the inner circumference of the casing 2. On the other hand, a partition wall 2A, which is in sliding contact with the outer circumference of the annular cross-section portion 3A, is formed at a symmetrical position on the inner circumference of the casing 2.

As shown in FIG. 2, side plates 4 and 5 are fastened to both ends of the casing 2 by bolts 6 passing through the outside of the casing 2. These side plates 4
Thrust bearings 15 and 16 for axially supporting the vane 3 are attached to and 5.

In this manner, the vane 3, the partition wall 2A, and the side plates 4 and 5 define four oil chambers 7, 8, 9, and 10 inside the casing 2.

The tip of the swing shaft 1 is rotatably supported by a bearing 11 provided on the side plate 4. Further, the base end of the swing shaft 1 rotatably penetrates the side plate 5 via an oil seal 12, a bearing 13, and a dust seal 14.

A hollow portion 1A is formed at the tip of the swing shaft 1, and an oil reservoir chamber 18 communicating with the hollow portion 1A through an orifice 17 is attached to the side plate 4. A volume elastic body 19 that expands and contracts according to a pressure change is accommodated in the oil reservoir chamber 18.

The hollow portion 1A communicates with the oil chambers 7 to 10 through a passage 20 penetrating the swing shaft 1 and the vane 3.
Further, a plate-like check valve 21 is attached to the vane 3 so as to face the openings of these passages 20.

The passage 20 is composed of a through hole 20A penetrating the swing shaft 1 and the vane 3 in the axis transverse direction, and a port 20B formed in the vane portion 3A at a right angle to the through hole 2A.
Both ends of 0A are sealed by steel balls 22.

Further, the partition wall 2A is provided with a communication hole 23 for communicating the working oils flowing out from the oil chambers 7 to 10 through the gaps between the casing 2 and the side plates 4 and 5, respectively. An air bleeder 24 for bleeding air when injecting hydraulic oil is attached to the communication hole 23.

Next, the operation will be described.

When the swing shaft 1 swings, the vanes 3 that are splined to the swing shaft 1 swing together, and the oil chambers 7 and 9 and the oil chambers 8 and 10 simultaneously expand and contract.

For example, when the swing shaft 1 swings clockwise in FIG. 1, the oil chambers 7 and 9 contract and the oil chambers 8 and 10 expand.
Then, the hydraulic oil flows from the oil chambers 7, 9 to the oil chambers 8, 10 through the sliding gap of the vane 3, and the flow resistance at that time generates a damping force.

A part of this hydraulic oil flows out through the gap between the casing 2 and the side plates 4, 5 and communicates with each other through the communication hole 23.

When the hydraulic oil flowing into the expanding oil chambers 8 and 10 is insufficient, the hydraulic oil in the oil reservoir chamber 18 becomes the orifice 1.
7, hollow part 1A of swing shaft 1, passage 20 and check valve 2
It is supplied to these oil chambers 8 and 10 via 1. Therefore, the expanding oil chambers 8 and 10 do not become negative pressure.

When the swing shaft 1 swings counterclockwise, the oil chambers 8 and 10 contract, while the oil chambers 7 and 9 expand. In this case as well, the hydraulic oil circulates in the same circulation path as in the clockwise swing, and the same damping force is generated. If an orifice is provided in parallel with the check valve 21 between the oil chambers 8 and 10 and the port 20B, the generated damping force can be changed according to the swing direction of the swing shaft 1.

By the way, in this rotary damper,
Since the swing shaft 1 and the vane 3, the casing 2 and the side plates 4 and 5 are formed as independent members and are configured to be coupled at the time of assembly, the individual members are relatively simple in shape and easy to process. It is easy and can be formed by various methods such as sintering and aluminum die casting.

For this reason, for example, the swing shaft 1 is made of an iron-based material, while the vane 3 is made of an aluminum material having a higher thermal expansion property, and the casing 2 and the vane 3 are expanded by the expansion of the vane 3 due to the temperature rise. It is also possible to provide a function of compensating for a change in the damping force due to a change in the viscosity of the hydraulic oil by changing the clearance.

Further, the casing 2 and the side plate 4,
Since the structure in which 5 is coupled with the bolt 6 is adopted, the variation in the clearance between the vane 3 and the side plates 4, 5 is small.

[0028]

As described above, according to the present invention, since the vane and the swing shaft are coupled by the different diameter fitting and the side plates are fixed to the both ends of the casing with the bolts, these members are individually provided as independent members. Machining is possible, facilitating machining and selecting the material for each member.

Further, a hollow portion formed in the swing shaft and a passage penetrating the swing shaft and the vane in the transverse direction communicate the oil reservoir chamber and the oil chamber, and the check valve is opened in these passages of the vane. Since it is provided on the side plate, it is not necessary to form a passage in the side plate, and the side plate can be easily processed.

Therefore, the manufacturing cost of the rotary damper can be significantly reduced.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a rotary damper showing an embodiment of the present invention.

FIG. 2 is a composite view of an AOB arrow view and a CC arrow view in FIG.

[Explanation of symbols]

 1 rocking shaft 2 casing 3 vanes 4,5 side plate 6 bolts 7, 8, 9, 10 oil chamber 18 oil reservoir chamber 20 passage 21 check valve

Claims (1)

[Claims] 1. A vane is provided at a symmetrical position of an oscillating shaft that is concentrically arranged inside a cylindrical casing, and a partition is formed at a symmetrical position on the inner circumference of the casing. The vane and the partition and both ends of the vane are located. 4 oil chambers are defined inside the casing by the side plates, and the damping force against the swing of the swing shaft is generated by the flow resistance of the working oil flowing between these oil chambers through the vane sliding gap. In the rotary damper provided with an oil reservoir that compensates for fluctuations in the amount of oil in these oil chambers, and a check valve that guides the hydraulic oil in the oil chambers to the oil chambers, the vanes and the swing shaft are The side plates are coupled by different-diameter fittings, and the side plates are fastened to both ends of the casing with bolts, and a hollow portion formed in the swing shaft and the hollow portion and the swing shaft and the vane penetrate in the transverse direction to reach each oil chamber. Through the passage and the oil reservoir chamber A rotary damper characterized in that the check valve is provided at the opening of these passages of the vane while communicating with each oil chamber.