JPH08303512A - Rotary damper - Google Patents

Abstract

PURPOSE: To effectively eliminate cavitation generated in a hydraulic fluid chamber on the extension side, simplify the constitution of oil ways, and reduce the number of mandays for processing by keeping oil resistance for supply of hydraulic oil in a rotary damper low. CONSTITUTION: In a sealless type rotary damper 1, a back surface side of a partition wall member 12 closing side parts of hydraulic oil chambers 23, 24 is composed as an oil tank chamber 37, and check valves 39, 40 are respectively provided on the partition wall member 12 corresponding to the hydraulic oil chambers 23, 24 parted by a separation block and a wane, so the oil tank chamber 37 is directly communicated with the hydraulic oil chambers 23, 24 through the check valves 39, 40. The constitution of oil ways for supply of hydraulic oil can thus be simplified.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealless rotary damper which utilizes a swinging motion to damp a vehicle or other external vibration.

[0002]

2. Description of the Related Art Conventionally, as a sealless type rotary damper, for example, 1994 patent application publication 2009
The one disclosed in Japanese Patent No. 71 is known.

That is, in this device, side cases forming pressure resistant wall surfaces are respectively applied to openings at both ends of a cylindrical casing, and these side cases are fixed to the casing with bolts to close the openings at both ends. .

The rotor shaft is rotatably supported at the center of the casing through bearings provided on both side cases, and is integrally connected to a vane body having radial vanes by serration.

The outer protruding end portion of the rotor shaft is sealed by a seal interposed between the rotor shaft and the side case,
The inside of the casing is kept oil-tight by the seal, and the inside of the casing is divided into a plurality of hydraulic oil chambers by the separate block provided on the inner peripheral surface of the casing and the vanes extending radially from the rotor shaft side.

Thus, when a relative swing motion occurs between the casing and the rotor shaft, one of the hydraulic oil chambers located on both sides of the vane and the separate block is compressed and the other expands.

The hydraulic oil chambers on the compression side and the expansion side communicate with each other through a gap around the vane with respect to the casing and the side case, as well as a gap around the separate block with respect to the vane body and the side case.

Therefore, the hydraulic fluid pushed out from the hydraulic fluid chamber on the compression side toward the hydraulic fluid chamber on the expansion side flows through the above-mentioned gaps, and a damping force is generated by the flow resistance of the hydraulic fluid passing through the gaps.

On the other hand, in order to constantly fill the hydraulic oil chamber with hydraulic oil and to compensate for expansion and contraction of the hydraulic oil due to temperature changes, the inside of the rotor shaft is free pistoned into the gas chamber and the oil tank chamber. It is divided into

The oil tank chamber communicates with each hydraulic oil chamber through the gap between the rotor shaft and the vane body with respect to the bearing, and also communicates with the serration portion between the rotor shaft and the vane body.

Further, this serration portion is further communicated from the vane body and the vertical holes drilled over the vane to the respective hydraulic oil chambers through the lateral holes of the vane and the check valves provided at the outlet portions of these lateral holes. ing.

Thus, when the hydraulic oil is insufficient in the hydraulic oil chamber due to a decrease in temperature, the check valve is opened from the oil tank chamber through the clearance between the rotor shaft and the bearing, the serration portion, and the vertical and horizontal holes of the vane portion. On the contrary, the hydraulic oil is supplied to the hydraulic oil chamber,
When the hydraulic fluid in the hydraulic fluid chamber becomes excessive due to thermal expansion, the excess hydraulic fluid is absorbed by being pushed out from the gap between the bearing and the vane body to the oil tank chamber through the gap between the rotor shaft and the bearing.

When the rotary damper is operating,
If a shortage of hydraulic oil occurs in the hydraulic fluid chamber on the expansion side due to the hydraulic fluid pushed out from the hydraulic fluid chamber on the compression side through the above gap into the oil tank chamber, open the check valve through the same path as when the temperature dropped previously. The hydraulic oil is replenished into the hydraulic oil chamber on the expansion side while opening.

[0014]

As described above, in the above-mentioned conventional example, the excess amount of the hydraulic oil generated in the hydraulic oil chamber is compensated by the clearance around the bearing, and the shortage is compensated for by the vertical hole on the vane side. A check valve is provided at the lateral hole and at the outlet of the lateral hole to compensate.

Therefore, even during the normal operation of the rotary damper, a part of the pressure hydraulic oil in the hydraulic oil chamber on the compression side flows into the oil tank chamber through the clearance around the bearing for excess oil escape, Dynamic pressure is applied to the free piston in the rotor shaft.

Then, from the oil tank chamber, the equivalent amount of hydraulic oil passes through the vertical holes and the horizontal holes on the vane side, opens the check valve, and is supplied to the hydraulic oil chamber on the expansion side.

As a result, in particular, when the rotary damper oscillates at a high frequency, expansion is caused by a delay in the followability of the free piston and an increase in flow passage resistance due to the length of the oil passage structure for replenishing hydraulic oil. There will be a delay in replenishing hydraulic oil to the hydraulic oil chamber on the side.

This delay in replenishing the hydraulic oil causes cavitation in the hydraulic oil chamber on the expansion side, and reduces the initial damping force at the time of the subsequent reversal of the swing direction to disturb the damping force characteristics. become.

Not only that, but also in the construction of the oil passage, it takes a great deal of work to process the oil passage, and since it is necessary to close the tip of the vertical hole with a blind plug, the number of parts is large and the assemblability is high. Also brings the inconvenience of being bad.

Therefore, an object of the present invention is to remove the cavitation generated in the hydraulic fluid chamber on the expansion side by keeping the hydraulic fluid resistance for replenishing hydraulic fluid low, and at the same time, simplify the construction of the hydraulic fluid passage. To provide this type of rotary damper that can

[0021]

SUMMARY OF THE INVENTION In the present invention, the above-mentioned object is to configure an oil tank chamber on the back side of a partition wall member for partitioning the side of the hydraulic oil chamber, and to form each hydraulic oil chamber in the partition wall member. This is achieved by the first invention in which check valves are provided correspondingly and the oil tank chambers communicate with the respective hydraulic oil chambers through the check valves.

On the other hand, in the case where the damping force is changed in accordance with the swinging direction of the rotary damper, in addition to the first aspect of the present invention, the partition member further corresponds to one of the hydraulic oil chambers. This is achieved by the second invention in which an orifice for setting the expansion damping force ratio is provided in parallel with the check valve, and the one hydraulic oil chamber and the oil tank chamber communicate with each other through the orifice for setting the expansion damping force ratio. It

Further, a check valve is provided corresponding to one of the hydraulic oil chambers, and an orifice for setting the expansion / damping force ratio is provided corresponding to the other hydraulic oil chamber, and an oil tank chamber is provided through the check valve. The same can be achieved by the third invention in which one hydraulic oil chamber is communicated with the other hydraulic fluid chamber and the oil tank chamber is mutually communicated with each other through the orifice for setting the expansion damping force ratio.

Further, a check valve is provided corresponding to one of the hydraulic oil chambers, the oil tank chamber is communicated with the one hydraulic oil chamber through the check valve, and the one hydraulic oil chamber is connected in series to the vane. According to the fourth aspect of the present invention, which communicates with the other hydraulic oil chamber through the arranged extension force damping force ratio setting orifice and the check valve, the above object is achieved while changing the damping force according to the swing direction. be able to.

[0025]

In other words, according to the first and second aspects of the present invention, when the rotary damper is in operation, even if the hydraulic fluid in the hydraulic fluid chamber on the expansion side is insufficient, cavitation occurs. Even in this case, a check valve provided in the partition member is opened for the hydraulic oil chamber to supply the hydraulic oil directly from the oil tank chamber.

Therefore, since the hydraulic oil is supplied with almost no flow resistance, cavitation does not occur in the hydraulic oil chamber on the expansion side, and stable damping force characteristics are always exhibited.

Particularly, in the second invention, when the working oil chamber communicating with the oil tank chamber through the orifice for setting the expansion / damping force ratio is on the expansion side, the orifice is provided in parallel with the check valve. Not only is hydraulic oil replenished from the inside, but on the contrary, when the hydraulic oil chamber is on the compression side, the internal pressure hydraulic oil is pushed through the orifice into the oil tank chamber. Therefore, the damping force varies depending on the swinging direction of the rotary damper.

Also according to the third aspect of the invention, the hydraulic oil is replenished directly from the oil tank chamber through the check valve provided in the partition member or the orifice for setting the expansion / damping force ratio to the hydraulic oil chamber on the expansion side. To be done.

As a result, since the hydraulic oil is replenished with almost no flow path resistance, cavitation does not occur in the hydraulic oil chamber on the expansion side, and stable damping force characteristics are always exhibited.

Moreover, when the hydraulic oil chamber on the side having the orifice for setting the expansion damping force ratio is on the compression side, the pressure hydraulic oil in the hydraulic chamber is the orifice for setting the expansion damping force ratio. Is also pushed out toward the oil tank chamber, so that a difference in damping force occurs depending on the swinging direction of the rotary damper.

Further, according to the fourth aspect of the invention, the expansion of the hydraulic oil chamber on the expansion side is performed directly through a check valve provided on the partition member or at that time, from the hydraulic oil chamber on the compression side. The hydraulic fluid is supplied to the hydraulic fluid chamber on the expansion side through the orifice for setting the damping force ratio and the check valve.

As described above, since the hydraulic oil is replenished with almost no flow path resistance, cavitation does not occur in the hydraulic oil chamber on the expansion side, and moreover, depending on the swing direction of the rotary damper. There will be a difference in damping force.

[0033]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the drawings.

1 and 2 show one embodiment of a rotary damper to which the present invention is applied. FIG. 1 is a cut development view taken along the line BB of FIG. 2, and FIG. FIG. 2 is a sectional side view taken along the line AA in FIG. 1.

The rotary damper 1 is integrally connected to a main body portion 5 formed by covering the opening portions at both ends of a cylindrical casing 2 with side cases 3 and 4 through a spline 6, and to the main body portion 5. And a rotor portion 9 composed of a vane body 8 and rotatably mounted.

The casing 2 constitutes the outer peripheral pressure-resistant wall surface of the main body portion 5, and the inner peripheral surfaces at both ends thereof are cut out while leaving a predetermined size in the central portion, so that the both end portions are formed as thin portions 2a and 2b, respectively. Has been formed.

Further, there are two on the inner peripheral surface with a phase difference of 180 degrees (of course, there may be one or three or more).
The separate blocks 10 and 11 (see FIG. 2) are fixed, and these separate blocks 10 and 11 are configured such that their widths are adapted to a predetermined size in the central portion of the casing 2.

On the other hand, the side cases 3 and 4 cooperate with the casing 2 to form pressure-resistant wall surfaces on both sides of the main body portion 5, and rotatably support the rotor portion 9 with respect to the main body portion 5 through the rotor shaft 7. Play a role to do.

In the case of this embodiment, the side case 3 is a partition wall member 12 made of a thick disk which has a role as a bearing member for the rotor shaft 7 and a role as a thrust bush for bearing a thrust load. The thin cap 13 for sealing is divided into two members, respectively.

Similarly, the side case 4 also functions as a bearing member and a thick disk-shaped partition wall member 14 that also functions as a thrust bush that bears the thrust load.
And a thin cap 15 having a sealing seal 16 fitted therein.

The thin cap 13 is provided with a hydraulic oil injection hole 17, and the injection hole 17 is sealed with a steel ball 18 after the hydraulic oil is injected into the rotary damper 1.

As described above, the side cases 3 and 4 are composed of the bearing partition wall member 12 and the sealing thin wall cap 13 each having a simple shape, and the bearing partition wall member 14 and the sealing thin wall cap 15 similarly. As a result, it becomes possible to facilitate the processing and reduce the weight while ensuring the original role described above.

The outer peripheral portions of the partition members 12 and 14 on the back side are chamfered to form annular grooves with the thin caps 13 and 15, and seals 19 and 20 are fitted in the annular grooves. I am disguised.

The side cases 3 and 4 described above are inserted to the ends of the thin-walled portions 2a and 2b at both ends of the casing 2 with the partition members 12 and 14 inside.

Thereafter, the thin-walled portions 2a and 2b at both ends are bent along the thin-walled caps 13 and 15 and caulked, so that they are integrally attached to the casing 2.

Thus, the casing 2 and the side cases 3 and 4 cooperate with the rotor portion 9 including the rotor shaft 7 and the vane body 8 to define a sealed working chamber inside the main body portion 5. .

From the outer peripheral surface of the vane body 8, the casing 2
The same number of vanes 21, 22 (see FIG. 2) as the side separate blocks 7, 8 are projected with a phase of 180 degrees.

The vanes 21 and 22 are also adapted to the predetermined size of the central portion of the casing 2 like the separate blocks 10 and 11.

As shown in FIG. 2, the heights of the separate blocks 10 and 11 and the vanes 21 and 22 are such that the tips of the separate blocks 10 and 11 are in sliding contact with the outer peripheral surface of the vane body 8 and the inner peripheral surface of the casing 2. It is made in.

As a result, the separate blocks 10, 1
1 and the vanes 21, 22 cooperate with each other to divide the working chamber into four working oil chambers 23, 24, 25, 26, and
As the vane body 8 rotates, the hydraulic oil chambers 23 and 25 and the hydraulic oil chambers 24 and 26 are alternately compressed and expanded.

On the other hand, the rotor shaft 7 has the body portion 5 through the partition members 12 and 14 in the side cases 3 and 4.
It is rotatably supported by and is made hollow by using a pipe material.

One end of the rotor shaft 7 penetrates through the thin cap 15 of the side case 4 and extends to the outside, and a protruding portion thereof is oil-tightly sealed by a seal 16.

The other end of the rotor shaft 7 is
The side case 4 extends close to the thin cap 13 and opens in the thin cap 13.

An outer open end portion of the rotor shaft 7 is formed in a taper 27 tapering outwards to form a connecting portion 28, and a block 29 is formed at the connecting portion 28. It is fitted.

The block 29 is provided with a seal 30 on the outer periphery thereof to keep the hollow portion 31 in the rotor shaft 7 airtight to the outside, and the coupling portion 28 of the rotor shaft 7 is backed up from the inside to deform the portion. It also plays a role in blocking.

In addition to the above, a screw hole 32 is formed on the outer surface of the block 29, and the screw hole 32 is utilized when connecting the rotor shaft 7 to the outside.
It can be pulled outwards.

As a result, the block 29 pulled outwards cooperates with the taper 27 to ensure the sealing action of the hollow portion 31, and the spline formed on the outer peripheral surface by expanding the diameter of the connecting portion 28. It plays the role of eliminating 33 play.

When the rotary damper 1 having the above structure is used, one of the connecting portions 28 of the rotor shaft 7 in the casing 2 on the main body portion 5 side and the rotor portion 9 is attached to the external fixed portion, and the other is attached to the external vibrating body. I will attach it.

As a result, the casing 2 is separated from the external vibrating body.
Alternatively, when the reciprocating rocking motion is transmitted to the body portion 5 or the rotor portion 9 through the rotor shaft 7, the separate blocks 10 and 11 on the body portion 5 side and the vanes 21 and 22 on the rotor portion 9 side relatively rock about the axis. Exercise.

Along with that, the main body portion 5 sandwiched between the separate blocks 10 and 11 and the vanes 21 and 22.
The hydraulic oil chambers 23 and 25 therein and the hydraulic oil chambers 16 and 18 are alternately compressed and expanded.

Then, the working oil in the working oil chamber on the compressed side has a gap between the tips of the vanes 21, 22 and the casing 2, both side surfaces of the vanes 21, 22 and the partition member 12,
14 and the separate block 10, 1
It flows through the gap between the tip of 1 and the vane body 8 and the gap between both side surfaces of the separate blocks 10 and 11 and the partition members 12 and 14 into the hydraulic fluid chamber on the expanding side.

Thus, during the normal operation of the rotary damper 1, a damping force is generated by the flow resistance of the working oil flowing through these gaps, and this damping force passes through the casing 2 or the rotor shaft 7 to the external vibrating body. Acting,
The motion of the vibrating body will be suppressed.

On the other hand, in the rotary damper 1 of this type, the hydraulic oil chamber 2 is affected by the temperature change of the hydraulic oil, external leakage, and the like.
If excess or deficiency occurs in the hydraulic oil enclosed in 6 to 18,
It directly adversely affects the damping action of the rotary damper 1.

Therefore, in order to prevent this, the hollow portion 31 of the rotor shaft 7 is divided into a gas chamber 36 on the block 29 side and an oil tank chamber 37 on the open end side by a free piston 35 having a seal 34 on the outer circumference. The gas chamber 36 and the oil tank chamber 37 constitute an accumulator.

The oil tank chamber 37 of the accumulator is
It extends from the open end of the rotor shaft 7 to the back side of the partition member 12 through a space 38 formed between the partition member 12 and the thin cap 13.

On the other hand, in the partition member 12, the space 38 is formed.
The check valves 39, 40, 41, 42 are respectively provided between the hydraulic oil chambers 23, 24, 25, 26 (constituting a part of the oil tank chamber 37) and the respective hydraulic oil chambers 23, 24, 25, 26.
2 is provided so as to penetrate therethrough, and an oil passage 43 is formed on the bearing surface of the rotor shaft 7 in the partition member 14.

Check valves 39, 40, 41, 42
Have the same structure, and as shown in FIG. 3, by forming the case 44 by drawing, a check ball 45 and a check spring 46 are provided in the case 44.
The cartridges are housed in a cartridge structure.

Then, the check valves 39, 40, 41, 42 are fitted into the partition wall member 12 through the case 44 and press-fitted, so that the oil tank chamber 37 is set in each of the hydraulic oil chambers 23, 24, 25, 26. On the other hand, the check valves 39, 40, 41, 42 are directly communicated with each other.

As a result, when there is a shortage of the hydraulic oil sealed in the hydraulic oil chambers 23, 24, 25, 26 due to temperature change of the hydraulic oil, external leakage, etc., the check valve 39 provided on the partition member 12, While opening 40, 41, 42, the hydraulic oil in the oil tank chamber 37 is transferred to the hydraulic oil chambers 23, 24,
Inhale 25 and 26 to make up for this shortage.

On the contrary, when it becomes excessive, the working oil in each working oil chamber 23, 24, 25, 26 is passed through the gap between the vane body 8 and the rotor shaft 7 with respect to the partition member 12 to the oil tank chamber. It is pushed out to 37 and the excess of the above-mentioned hydraulic oil is removed to the oil tank chamber 37 and absorbed.

Thus, the relatively slow operating oil chambers 23, 24, 2 due to changes in operating oil temperature, external leakage, etc.
The excess or deficiency of the hydraulic oil in 5, 26 is compensated by the oil tank chamber 37 as described above.

Further, since the excessive amount of hydraulic oil is absorbed as described above, the rotary damper 1
Even during the normal operation of, the pressure hydraulic oil in the compressed hydraulic oil chamber tends to be pushed out into the oil tank chamber 37 through the gap between the vane body 8 and the rotor shaft 7 with respect to the partition member 12. .

However, with respect to such a rapid flow of hydraulic oil, the above-mentioned gap exerts a throttling effect to limit the flow and cut the dynamic pressure applied to the free piston 35 in the accumulator, In addition, the pressure hydraulic oil in the hydraulic fluid chamber on the compression side is pushed out to the hydraulic fluid chamber on the expansion side to prevent cavitation from occurring in the hydraulic fluid chamber on the expansion side.

That being said, as long as the above-mentioned gap exists, the pressure hydraulic oil in the hydraulic oil chamber on the compression side flows through the gap to the oil tank chamber, though it is a small amount. Cavitation may occur due to lack of hydraulic oil in the hydraulic oil chamber.

However, even in such a situation, the check valve provided in the partition wall member 12 opens to open the oil tank chamber 37, as in the case of the compensation effect when the operating oil is insufficient such as the temperature change of the operating oil or external leakage. The hydraulic oil inside is sucked into the hydraulic oil chamber on the expansion side.

The action of sucking the working oil into the working oil chamber on the expansion side is directly performed from the oil tank chamber 37 through the check valves 39, 40, 41 and 42 with almost no flow resistance.

As a result, in combination with the dynamic pressure cutting action on the free piston 35 in the accumulator, even if the rotary damper 1 oscillates at a high frequency, the expansion side hydraulic fluid chamber is Is immediately replenished with hydraulic oil.

This means that the cavitation generated in the hydraulic fluid chamber on the expansion side can be reliably eliminated, and the initial damping force drop at the time of the next reversal of the swing direction can be eliminated, so that a stable damping force characteristic can always be obtained. Will be secured.

In addition, these things make the oil tank chamber 37 pass through the check valves 39, 40, 41, 42 provided in the partition member 12 to the hydraulic oil chambers 23, 24, 25, 2 respectively.
This can be achieved with a simple oil passage configuration in which the communication with the No. 6 is made.

The hydraulic oil is injected into the rotary damper 1 through the injection hole 17 provided in the thin cap 13 on the side case 3 side.

That is, the hydraulic oil injected from the injection hole 17 into the rotary damper 1 pushes the free piston 35 while filling the oil tank chamber 37 and compresses the gas chamber 36 of the accumulator to increase its pressure.

When the hydraulic oil in the oil tank chamber 37 reaches a predetermined pressure, the check valve 3 provided in the partition member 12
9, 40, 41, 42 open and hydraulic oil chambers 23, 24, 2
The air in 5, 26 is pushed out into the oil tank chamber 37 through the gap between the vane body 8 and the rotor shaft 7 with respect to the partition wall member 12, and is replaced with hydraulic oil.

In parallel with this, the oil tank chamber 3
The hydraulic oil in 7 is also injected into the portion of the seal 16 from the gap between the rotor shaft 7 and the partition wall member 12 through the oil passage 43 of the spline 6 and the partition wall member 14 to prevent the accumulation of air in that portion.

The hydraulic oil chambers 23, 24, 2
The air pushed out from the portions of 5, 26 and the seal 16 to the oil tank chamber 37 is taken out of the oil tank chamber 37 through the hydraulic oil injector.

Then, the hydraulic oil injection hole 17 of the thin cap 13 is sealed by the steel ball 18.

As described above, in the embodiments shown in FIGS. 1 and 2, the rotary damper which exhibits the same damping force characteristic regardless of the swing direction has been described. However, the embodiment shown in FIG.
An example in which the damping force is changed according to the swing direction is shown.

In the embodiment shown in FIG. 4, the partition member 1 is provided corresponding to one of the hydraulic oil chambers 23 and 25 arranged diagonally.
In FIG. 2, orifices 47 and 48 for setting the compression damping force ratio are additionally arranged in parallel with the check valves 39 and 41, and the orifices 47 and 48 for setting the compression damping force ratio are also used to operate the hydraulic oil chambers 23 and 25 on one side. And the oil tank chamber 37 communicate with each other.

Therefore, according to this, as shown in FIG.
It can be easily understood that the same operation as that of the second embodiment can be performed based on the above description without needing to repeat the description here.

Moreover, in particular, according to this one, in addition to the above, when the hydraulic oil chambers 23, 25 having the orifices 47, 48 for setting the compression damping ratio are on the expansion side, the check valve 39 , 41, the hydraulic oil is replenished from the orifices 47, 48 for setting the expansion force damping force ratio.

Further, only when the hydraulic oil chambers 23 and 25 are, on the contrary, on the compression side, a part of the pressure hydraulic oil inside passes through the orifices 47 and 48 and the oil tank chamber 37.
When the rotary damper 1 swings in that direction, the decrease rate of the damping force is limited by the pressure loss of the orifices 47 and 48, and an appropriate difference is obtained between the damping force when swinging in the opposite direction. Will be given.

The embodiment of FIG. 5 also shows an example in which the damping force is changed according to the swinging direction of the rotary damper 1.

In FIG. 5, check valves 39 and 41 are provided in the partition wall member 12 corresponding to one of the hydraulic oil chambers 23 and 25 arranged diagonally, and these hydraulic oil chambers 23 and 2 are provided.
No. 5 arranged in series with the vanes 21, 22 and orifices 47, 48 for setting the expansion / damping force ratio and check valves 49, 5
It differs from the previous embodiment of FIG. 4 in that it communicates with the other hydraulic oil chamber 24, 26 through 0.

Also by this, the hydraulic oil chambers 23, 25
Is on the expansion side, the check valve 39 provided on the partition member 12,
The hydraulic oil is directly supplied from the oil tank chamber 37 through 41.

When the hydraulic oil chambers 24 and 26 are on the expansion side, the hydraulic oil chambers 23 and 2 which are on the compression side at that time are
5, hydraulic fluid is replenished through orifices 47 and 48 for setting the expansion / damping force ratio and check valves 49 and 50.

For this reason, since replenishment of these hydraulic oils is carried out with almost no flow path resistance, cavitation does not occur in the hydraulic oil chamber on the expansion side, and stable damping force characteristics are always exhibited.

Moreover, when the hydraulic oil chambers 23, 25 are on the compression side, a part of the pressure hydraulic oil in the hydraulic oil chambers 23, 25 is used for setting the expansion / damping force ratio orifices 47, 48 and the check valve 49. , Hydraulic fluid chamber 24 on the expansion side through 50,
Therefore, the damping force is different depending on the swinging direction of the rotary damper 1.

Furthermore, the embodiment of FIG. 6 also shows an example in which the damping force is changed according to the swing direction.

That is, in the embodiment of FIG. 6, the orifice 4 for setting the expansion / damping force ratio is set with respect to the partition member 12.
One hydraulic oil chamber 23, 25 in which 7, 48 are diagonally arranged
And corresponding to the other hydraulic oil chambers 24 and 26, only check valves 40 and 42 are provided.

As a result, even in this embodiment, when the hydraulic oil chambers 23 and 25 are on the expansion side, the hydraulic oil is directly supplied from the oil tank chamber 37 through the orifices 47 and 48 for setting the expansion force damping force ratio. Will be replenished.

On the other hand, when the hydraulic oil chambers 24 and 26 are on the expansion side, the check valves 40 and 42 provided in the partition member 12 directly pass through the oil tank chamber 37, as in the case of the embodiments of FIGS. Hydraulic oil is replenished.

Therefore, cavitation does not occur in the hydraulic fluid chamber on the expansion side, and stable damping force characteristics can always be exhibited.

When the hydraulic oil chambers 23, 25 are on the compression side, a part of the internal pressure hydraulic oil passes through the orifices 47, 48 for setting the expansion / damping force ratio, and the oil tank chamber 37.
Therefore, the damping force varies depending on the swinging direction of the rotary damper 1.

In the embodiments of FIGS. 4, 5 and 6, when the hydraulic oil chambers 23 and 25 are on the compression side, a low damping force is applied, and conversely, the hydraulic oil chambers 24 and 26 are compressed. It has been described that a high damping force is generated when it is on the side.

However, the arrangement of the check valves 39, 40, 41, 42 and the orifices 47, 48 for setting the expansion damping force ratio, and the operation of the check valves 49, 50 are not limited to these. By selecting the direction, a high damping force is generated when the hydraulic oil chambers 23 and 25 are on the compression side, and conversely, a low damping force is generated when the hydraulic oil chambers 24 and 26 are on the compression side. It goes without saying that you can do it.

[0105]

As described above, according to the first aspect of the present invention, the check valves in the oil passages that communicate the oil tank chambers with the respective hydraulic oil chambers are provided for the partition members, and the check valves are passed through these check valves. By connecting the oil tank chamber directly to each hydraulic oil chamber, while ensuring the workability of hydraulic oil injection and the temperature compensation function, the hydraulic oil on the expansion side is also operated during normal operation of the rotary damper. It is possible to reliably prevent even cavitation that occurs in the room and always exhibit stable damping force characteristics.

Further, in addition to the above, it is cut between the partition member and the rotor shaft that the hydraulic oil in the hydraulic oil chamber is transmitted as dynamic pressure to the oil tank chamber during normal operation of the rotary damper, and the hydraulic oil flows into the oil tank chamber. Since the flow rate of the working oil to be used can be limited, the oil tank chamber can be made compact.

Further, since the oil passage structure itself for communicating the oil tank chamber with each hydraulic oil chamber can be simplified, the assemblability is improved.

According to the invention of claim 2, in addition to the above effects, it is possible to make the damping force have a difference depending on the operating direction of the rotary damper.

Similarly, according to the third aspect of the present invention, it is possible to provide the damping force with a difference according to the operating direction of the rotary damper while securing the effect of the first aspect.

According to the invention of claim 4, the number of check valves can be reduced by half and the same effect as described above can be exhibited.

According to the fifth and sixth aspects of the present invention, the assembling property of the rotary damper can be further improved while ensuring the effects of the first, second, third and fourth aspects.

[Brief description of drawings]

FIG. 1 is a vertical sectional front view showing an embodiment of a rotary damper according to the present invention.

FIG. 2 is a vertical sectional side view of the same.

FIG. 3 is an enlarged sectional view showing only a check valve.

FIG. 4 is a vertical sectional side view showing another embodiment of the rotary damper.

FIG. 5 is also a vertical side view showing another embodiment of the present invention.

FIG. 6 is a vertical sectional side view showing still another embodiment of the rotary damper.

[Explanation of reference numerals] 1 rotary damper 2 casing 2a, 2b thin portion 3,4 side case 10,11 separate block 12,14 partition member 13,15 thin cap 21,22 vane 23,24,25,26 hydraulic fluid chamber 36 Gas chamber 37 Oil tank chamber 38 Space part which is a part of oil tank chamber 39, 40, 41, 42 Check valve 44 Check valve case 45 Check ball 46 Check spring 47, 48 Orifice damping force ratio setting orifice 49 , 50 check valves

Claims (6)

[Claims] 1. In a sealless type rotary damper, the rear surface side of a partition member that partitions the side of the hydraulic oil chamber is configured as an oil tank chamber, and each partition member is partitioned by a separate block and a vane. A rotary damper characterized in that a check valve is provided corresponding to each oil chamber, and the oil tank chamber is communicated with each hydraulic oil chamber through the check valve. 2. In a sealless type rotary damper, the rear surface side of a partition member that partitions the side of the hydraulic oil chamber is configured as an oil tank chamber, and each partition member is partitioned by a separate block and a vane. A check valve is provided in correspondence with the oil chamber, and an orifice for setting the expansion / damping force ratio is provided in parallel with the check valve in correspondence with one of the hydraulic oil chambers. A rotary damper, which communicates with the hydraulic oil chamber, and also allows the one hydraulic oil chamber and the oil tank chamber to communicate with each other through an orifice for setting the expansion / damping force ratio. 3. In a sealless type rotary damper, the rear surface side of a partition member that partitions the side of the hydraulic oil chamber is configured as an oil tank chamber, and each partition member is partitioned by a separate block and a vane. A check valve is provided corresponding to one hydraulic oil chamber of the oil chamber, the oil tank chamber is communicated with the one hydraulic oil chamber through the check valve, and the one hydraulic oil chamber is arranged in series with the vane. A rotary damper characterized in that it communicates with the other hydraulic fluid chamber through an orifice for setting the expansion / damping force ratio and a check valve. 4. In a sealless type rotary damper, the rear surface side of a partition member partitioning the side of the hydraulic oil chamber is configured as an oil tank chamber, and each partition member is partitioned by a separate block and a vane. A check valve corresponding to one hydraulic oil chamber in the oil chamber,
An orifice for setting the expansion damping force ratio is provided corresponding to the other hydraulic oil chamber, and the oil tank chamber is connected to one hydraulic oil chamber through the check valve, and the other hydraulic oil chamber and the oil tank chamber are connected. A rotary damper characterized in that they are communicated with each other through an orifice for setting the expansion force damping force ratio. 5. The rotary damper according to claim 1, wherein each check valve is individually housed in a case to form a cartridge structure, and the case of these check valves is press-fitted and fixed to a partition member or a vane. 6. The partition wall member is formed of a thick disk so that the partition wall member has a function as a bearing member of a rotor shaft, and a thin wall cap is applied to the back surface side of the partition wall member to form the partition wall member and the thin wall cap. And an oil tank chamber is formed between them, and the partition member and the thin wall cap are fitted into the thin wall portions formed on the inner peripheral surfaces of both ends of the casing and caulked and connected. 5
Rotary damper.