JP2837446B2 - Two-stage operation stay damper - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention is most suitable for assisting opening and closing operations of a back door in a hatchback vehicle, and furthermore, starts a contraction operation from its most extended state or its approximate state. The present invention relates to a two-stage operation damper which can sometimes temporarily prevent the contraction operation, and is most suitable for preventing the back door from flapping or an unexpected descent.

[Conventional technology and its problems]

Conventionally, the back door of a hatchback vehicle is provided with a stay damper for assisting the opening and closing operation of the hatchback vehicle.When the stay damper is fully extended, the back damper maintains the back door in a fully open state, such as snow cover and wind force. It is assumed that the back door is formed so as to be easily contracted by an external force so as not to operate the back door in the closing direction.

Therefore, a means for setting a high gas pressure inside the stay damper can be adopted so that a large contraction preventing force at the time of the maximum elongation, that is, a tension force can be exhibited, but a means for increasing the internal gas pressure is used. The adoption will unnecessarily increase the contraction operating force of the stay damper.

That is, in recent years, this type of stay damper is required to be formed so that the back door can be flipped high and the back door can be fully opened so as not to obstruct the loading and unloading of luggage. It is desired to increase only the holding force in the vicinity of the fully opened state without increasing the closing operation force. Conventionally, for example, between the rod body and the cylinder body through which the rod body is inserted in the expansion and contraction operation area. Then, the rod body side or the cylinder body side is rotated around the axis of the stay damper, or the member provided on the rod body side or the cylinder body side is rotated, etc. There are various proposals such as preventing protrusion or expansion and contraction of the cylinder body.

However, in the conventional two-stage operation stay damper as described above, the configuration for the two-stage operation requires a so-called stopper function from an external structural point of view, and the number of members is unnecessarily increased. And the stay damper itself is bulky.

The present invention has been made in view of the above-described circumstances, and the object thereof is to cause an unnecessarily increase in the number of members or to increase the size of the member itself.
An object of the present invention is to provide a two-stage operation stay damper which enables a two-stage closing of a back door in a hatchback vehicle, and can temporarily prevent the start of the contraction operation from the most extended state or the approximated state.

[Means for solving the problem]

In order to achieve the above object, a means of the present invention includes a cylinder body, and a rod body that is inserted into and retractable from the cylinder body via a piston portion, wherein the piston portion and the rod body are partitioned in the cylinder body. In the stay damper which is constantly urged in the extending direction by the gas pressure of the gas chamber, the cylinder body has a small diameter portion near the end to reduce the inner diameter, and is fixed to the rod body on the outer periphery of the rod body A stopper member,
A check seal sliding on the outer periphery of the rod body, a spring interposed between the stopper member and the check seal to urge the check seal toward the piston portion are provided, and the check seal is further provided on the outer periphery of the rod body. A bypass path is formed around the inner periphery of the small-diameter portion during the contraction operation in which the rod body is immersed from the maximum extension position in the cylinder body from the maximum extension position. The rod body contracts temporarily to prevent the contraction operation of the rod body, and when a large external force is applied to the rod body to cause contraction, the check seal opens the bypass passage and slides on the inner periphery of the small diameter portion to accompany the rod body. It is characterized by moving.

In this case, a free piston is slidably provided in the piston side oil chamber in the cylinder body, and a gas chamber partitioned by the free piston is provided, and the stay damper is moved by the gas pressure in the gas chamber. This is in support of the growing trend.

Similarly, when the piston slides inside the cylinder,
The piston portion is formed so as to generate a predetermined damping force.

Similarly, the small-diameter portion of the cylinder body is formed such that the thick portion in the vicinity of the opening end of the cylinder body is reduced in diameter from the outside, or the small-diameter portion is formed in the vicinity of the opening end of the cylinder body. It is formed by disposing a collar member around the circumference.

Further, the check seal and the spring are interposed directly on the outer periphery of the shaft portion of the rod body, or on the outer periphery of a collar member provided in parallel with the piston portion on the spigot portion of the rod body. Further, when the check seal is slid on the small-diameter portion, a chamber partitioned by the check seal is formed at the opening end side of the cylinder body in the rod-side oil chamber in the cylinder body, and hydraulic oil is provided in the chamber. Is formed so as to be able to stagnate.

Further, when the check seal is retracted by overcoming the urging force of the spring, a bypass passage formed in the outer periphery of the rod body or in the collar member of the outer periphery of the rod body is formed to be opened, and the opened passage is opened. The hydraulic oil in the rod-side oil chamber is formed to flow into the chamber via the bypass passage.

[Action]

When the back door of the hatchback vehicle is opened, the rod body projects from the cylinder body by the action of the urging force in the extending direction due to the gas pressure, and the extending operation becomes possible.

At the time of the above extension operation, the check seal disposed on the outer peripheral side of the rod body comes into sliding contact with the small-diameter portion formed on the cylinder body at a predetermined location, that is, in a specific stroke area. The extension operation is temporarily stopped by the sliding resistance at that time.

That is, when the check seal slides on the small-diameter portion, the flow of the hydraulic oil that has been free between the check seal and the inner circumference of the large-diameter cylinder body is prevented.

As a result, since the bypass passage is also closed, the hydraulic oil is temporarily stagnated in the chamber formed between the check seal and the opening end side of the cylinder body, and the extension operation of the stay damper is temporarily stopped. Is blocked. When an operating force in the extension direction is further applied to the rod body from this state, the check seal is tilted inward, and the operating oil in the chamber flows out through the gap between the check seal and the small diameter portion to the maximum extension position. Extend.

Further, when an external force in the contracting direction is applied to the rod body from the most extended state, the check seal slidably contacting the small diameter portion of the cylinder body retreats to open the bypass passage, and the hydraulic oil from the rod-side oil chamber side receives the hydraulic oil from the chamber. And the contraction operation of the stay damper is enabled.

That is, a two-stage operation can be performed when the stay damper is extended.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments.

As shown in FIG. 1, a two-stage operation stay damper according to one embodiment of the present invention includes a cylinder body 1, a rod body 2 that is inserted into and retractable from the cylinder body 1, and a tip end of the rod body 2. Piston part 3 which is provided continuously and slides inside cylinder 1
And

One cylinder has a small-diameter portion 10 whose inner diameter is reduced over an appropriate section at an arbitrary position near the opening end 1a, which is the left end in the drawing.

In this embodiment, the small-diameter portion 10 is formed such that the thick portion of the cylinder body 1 is reduced in diameter from the outside.

On the other hand, the cylinder 1 has a bearing member 7 and an oil seal 8 in series on the inner periphery of the opening end 1a so as to close the opening end thereof. The rod body 2 slidably penetrates the shaft core of the oil seal 8 and the oil seal 8.

The cylinder 1 has an annular stopper 9 caulked and fixed to the inner periphery near the opening end 1a.

The annular stopper 9 has an appropriate gap 9a between its inner periphery and the outer periphery of the rod body 2.
A stopper member 6 disposed on the rod body 2 side described later can be inserted therein.

By the way, the above-mentioned two-stage operation stay damper has a free piston slidably in a piston side oil chamber B in the cylinder body 1 except for a push-up type mounting in which the piston rod 2 is lower even when the piston rod 2 is opened and closed. And a gas chamber defined by the free piston. The gas pressure in the gas chamber urges the stay damper to extend.

And this two-stage operation stay damper is a cylinder body 1
When the piston portion 3 slides inside, a predetermined damping force can be generated by a damping valve 30 disposed in the piston portion 3.

On the other hand, in this embodiment, the rod 2
The check seal 4 is provided directly on the outer periphery of the second seal 2a, and a spring 5 for urging the check seal 4 in the forward direction, which is to the right in the drawing.

The distal end 5 a of the spring 5 is adjacent to the proximal end 4 a of the check seal 4, and the proximal end 5 b of the spring 5 is locked by the stopper member 6.

A tip 4b of the check seal 4 is formed in a substantially cylindrical shape between the valve stopper 31 of the piston 3 and the step 2b of the rod body 2 and is a stopper member which is clamped.
It is in contact with 32 freely.

Further, the outer peripheral lip portion 4c of the check seal 4 is
At the time of the extension operation in which the rod body 2 is protruded from the inside of the cylinder 1 and is in the most extended state shown in FIG. In this sliding contact, the repulsive force of the stay damper on the compression side is increased only in the sliding contact section.

Therefore, in the two-stage operation stay damper, when the outer peripheral lip portion 4c of the check seal 4 is slidably contacted with the inner periphery of the small diameter portion 10, the above-mentioned rod-side oil chamber A in the cylinder body 1 The chamber C defined by the check seal 4 is the cylinder body 1
Is formed on the side of the open end 1a, and is formed so that the operating oil is stagnated in the chamber C.

Further, as shown in FIG. 2, when the check seal 4 is retracted by overcoming the urging force of the spring 5, the two-stage operation stay damper has a bypass formed by a cutout groove 2c opened in the rod body 2. The portion L is formed to be opened, and the hydraulic oil in the rod-side oil chamber A is formed to flow into the chamber C via the opened bypass passage L.

Therefore, in the rod body 2 according to the present invention, it is assumed that the outer periphery of the shaft portion 2a is formed to have excellent slidability, and in this embodiment, it is assumed that the rod portion 2 is formed by chrome plating.

The stopper member 6 has a flange portion 6a for abutting the base end 5b of the spring 5, and has a notch hole 6b in the flange portion 6a to allow passage of hydraulic oil, and for example, ,
It is fixed to the outer periphery of the shaft portion 2a of the rod body 2 by an appropriate means such as projection welding.

Therefore, the two-stage operation stay damper according to the present invention formed as described above operates as follows.

For example, when the back door of a hatchback vehicle is opened or the like, the stay damper is extended, and the rod body 2 from inside the cylinder body 1 is actuated by the action of the urging force in the extending direction due to gas pressure at the stay damper. As a result, the extension operation is positively permitted.

At that time, the hydraulic oil from the rod-side oil chamber A in the cylinder body 1 passes through the piston portion 3 and flows into the piston-side oil chamber B in the cylinder body 1, and at this time, the damping in the piston portion 3 A predetermined amount of damping force is generated by the valve 30, and its relatively slow extension operation is enabled.

At this time, in the piston side oil chamber B, the gas chamber partitioned by a free piston (not shown) expands to move the free piston, and the piston side oil chamber B
Eliminate hydraulic oil shortage inside.

When the above-described extension operation is performed for a predetermined stroke, the check seal 4 provided on the outer periphery of the shaft portion 2a of the rod body 2 is used.
Comes into sliding contact with the small diameter portion 10 formed on the inner periphery of the cylinder body 1, and in the direction in which the stay damper is further extended, the outer peripheral lip portion 4 c of the check seal 4 is so-called inclining. A gap is formed between the outer circumference of the outer lip portion 4c and the inner circumference of the small-diameter portion 10, and the hydraulic oil stagnated in the chamber C through the gap flows into the rod-side oil chamber A. To allow further extension of the stay damper.

When the stay damper is in the most extended state, the first
As shown in the drawing, a stopper member 6 fixed on the outer periphery of the shaft portion 2a of the rod body 2 collides with a stopper 9 fixed on the cylinder body 1 side. Is prevented from elongating.

At this time, the check seal 4 is attached to the rod 2
, And the bypass passage L is kept closed, so that the stay damper is maintained in the most extended state.

On the other hand, when the direction of the operating force acts in the direction of contracting the stay damper from the most extended state of the stay damper shown in FIG. 1, the check seal 4 slidably contacting the small diameter portion 10 of the cylinder body 1. Of the outer peripheral lip portion 4c tends to be in close contact with the small-diameter portion 10, so that the chamber C
There is no replenishment of hydraulic oil from the rod-side oil chamber A side, so that a so-called negative pressure is generated in the chamber C, and the repulsive force of the sliding contact section with the small diameter portion of the stay damper increases. Become.

When the stay damper is contracted with a larger external force, as shown in FIG. 2, the check seal 4 retreats with respect to the rod body 2 and has been closed by the check seal 4 until then. The bypass passage L is opened to allow the hydraulic oil in the rod-side oil chamber A to flow into the chamber C, and the stay damper to contract.

In addition, the above-described contraction operation is performed by sliding the stay damper with the small-diameter portion even in a state where the stay damper is close to the most extended state, that is, in a half-open state before the back door of the hatchback vehicle is fully opened. This is possible if it is a contact section.

FIG. 4 shows the bypass path L formed in the rod body 2 in the above-described embodiment, and it is assumed that the bypass path L is formed by the cutout groove 2c. It may be composed of the notch 2d.

FIG. 5 shows a two-stage operation stay damper according to another embodiment of the present invention. The two-stage operation stay damper is basically the same as the embodiment of FIG. 1 described above. Is formed.

Accordingly, the same parts of the constituent members will be denoted by the same reference numerals in the drawings, and detailed description thereof will be omitted. Hereinafter, the different points will be mainly described.

That is, in the two-stage operation stay damper according to this embodiment, the small-diameter portion 10 formed on the cylinder body 1 side has the stopper 9 fixed to the inner periphery near the opening end 1a of the cylinder body 1. The extended portion 9b is formed by being provided on the inner peripheral side of the cylinder body 1.

That is, in the two-stage operation stay damper according to this embodiment, the small diameter portion 10 is formed without reducing the diameter of the cylinder body 1 from the outer peripheral side.

Further, in the two-stage operation stay damper according to this embodiment, as shown in FIG. 6, the bypass path L has a vertical hole 2e formed in the shaft core of the rod body 2, and a vertical hole 2e. 2c and a horizontal hole 2f communicating with the lower end side, which is the left end in the figure.

The upper end of the vertical hole 2e, which is the right end in the drawing, opens into the piston side oil chamber B in the cylinder body 1. On the other hand, the outer peripheral end of the horizontal hole 2f is inside the cylinder body 1. The check seal 4 is closed at the open end of the rod side oil chamber A.

The inner periphery of the upper end, which is the right end in the drawing, of the extending portion 9b is a so-called tapered surface 9c, and when the stay damper is in the most compressed state, the outer peripheral lip portion 4c of the check seal 4 is Care is taken to facilitate smooth entry into the small diameter portion 10 formed by the extension portion 9b.

Although the bypass passage L in this embodiment is formed by a vertical hole 2e and a horizontal hole 2f formed in the rod body 2, the bypass passage L is replaced with the embodiment shown in FIG. May be formed by the notch groove 2c or the notch portion 2d.

Therefore, in the case of this embodiment, since the small diameter portion 10 can be formed without reducing the diameter of the cylinder body 1 from the outer peripheral side, there is an advantage that the appearance of the cylinder body 1 does not need to be changed.

FIG. 7 shows a two-stage operation stay damper according to still another embodiment of the present invention. Even in the case of the two-stage operation stay damper, it is basically the same as the embodiment of FIG. They are formed similarly.

Therefore, in this embodiment, the same parts of the constituent members are denoted by the same reference numerals in the drawings, detailed description thereof will be omitted, and different points will be mainly described below.

That is, in the embodiment shown in FIG. 7, the check seal 4 and the spring 5 interposed on the outer periphery of the rod body 2 constituting the two-stage operation stay damper are provided with a piston part on the spigot part 2g of the rod body 2. It is characterized in that it is interposed on the outer periphery of the collar member 20 arranged in series with the collar member 3.

That is, the collar member 20 is formed in a tubular body with a flange, and has a flange portion 20b at the tip of the main body portion 20a abutting on the stepped portion 2b of the rod body 2, and the main body portion 20a It is assumed that a bypass path L including a cutout groove 20c and the like is provided on the outer periphery.

The flange 20b serves as a stopper, and the lower end face which is the left end face in the drawing is the stopper 9 which becomes the right end face in the drawing.
Is to be in contact with the upper end surface of the.

Further, the collar member 20 is locked to the piston portion 3 with its tip being guided into the stopper member 32, that is, at the spigot portion 2g of the rod member 2, Is sandwiched between the stepped portion 2b and the piston portion 3.

Therefore, in this embodiment, the shaft 2a of the rod body 2
Needless to say, the fixing of the stopper member 6 to the outer periphery is omitted.

A notch hole 20d is formed in the flange portion 20b,
An annular groove 2h is formed in the spigot portion 2g, and a main body portion 20a of the collar member 20 is provided in the annular groove 2h.
A seal 21 is provided in close contact with the inner periphery of.

By the way, even in this embodiment, the cylinder body 1
It is a matter of course that the small-diameter portion 10 is provided, but in this embodiment, the reduced-diameter portion for forming the small-diameter portion 10 extends to the open end 1a of the cylinder body 1. There are features.

However, in the two-stage operation stay damper according to the present invention, when it is intended to set the diameter of the rod body 2 to be large so as to reduce the negative pressure in the chamber C, the broken line diagram in FIG. As shown, the inner diameter of the opening end 1a side of the cylinder body 1 may be set to be larger than the inner diameter of the small-diameter portion 10, that is, the outer diameter of the opening end 1a may be larger than the outer diameter of the small-diameter portion 10. Of course it is good.

Therefore, according to this embodiment, since the bypass path L is formed on the outer periphery of the collar member 20, the collar member
By simply changing 20, the bypass path L can be changed. That is,
The characteristics of the subsequent stroke of the two-stage actuating stay damper according to the present invention can be changed, and by selecting the inner diameter of the opening end 1a of the cylinder body 1 and the diameter of the rod body 2, the magnitude of the so-called holding force at the time of extension / extension is extended. There is an advantage that can be selected.

(Effects of the Invention) As described above, according to the present invention, the stay damper for assisting the opening / closing operation of the back door in the hatchback vehicle can, of course, enable the back door to be closed in two steps. During manufacture, there is an advantage that the number of members is not unnecessarily increased and the stay damper itself is not bulky.

According to the present invention, when an external force such as snowfall or wind acts in a direction of contraction from the most extended state or an approximate state thereof, the outer peripheral lip portion of the check seal has a cylinder body. Therefore, there is no replenishment of hydraulic oil from the rod-side oil chamber side in the chamber, so that a so-called negative pressure is generated in the chamber, and the repulsive force of the sliding contact section There is an advantage that will be increased.

Further, according to the present invention, a small-diameter portion whose inner diameter is reduced is provided at an arbitrary position on the cylinder body side, and a check seal that slides on the small-diameter portion is disposed on the rod body side,
In particular, at the time of the extension operation, the check seal is slid in contact with the small-diameter portion, and the check oil temporarily stagnates the working oil in a chamber defined on the opening end side of the cylinder body by the check seal, whereby the stay damper is stopped. It is said that it is formed so as to increase the repulsive force at the time of contraction, so that when contracting the back door, the user etc. does not need so-called adjustment work, and the function of the internal mechanism is safe and reliable. There is also an advantage that a desired two-stage closing operation can be performed.

[Brief description of the drawings]

FIG. 1 is a partial longitudinal sectional view showing a main part of a two-stage operation stay damper according to an embodiment of the present invention, FIGS. 2 and 3 are half partial longitudinal sectional views showing an operating state thereof, and FIG. FIG. 5 is a partial longitudinal sectional view showing a main part of a two-stage operation stay damper according to another embodiment of the present invention, FIG. 6 is a transverse sectional view of the rod body, and FIG. FIG. 11 is a partial longitudinal sectional view showing a main part of a two-stage operation stay damper according to still another embodiment of the present invention. [Explanation of Symbols] 1 ... Cylinder body, 1a ... Open end 2 ... Rod body, 2a ... Shaft section 2g ... Inlay section, 3 ... Piston section 4 ... Check seal, 4a, 5b ... Base end 4b, 5a: Tip, 4c: Outer lip 5: Spring, 5a: Tip 6, 32: Stopper member 10: Small diameter portion, 20: Collar member A: Rod side oil chamber, B: piston-side oil chamber C: chamber, L: bypass passage

Claims (1)

(57) [Claims] The invention has a cylinder body and a rod body which is inserted into and retractable from a cylinder body via a piston part, and the piston part and the rod body are always extended by a gas pressure of a gas chamber partitioned in the cylinder body. In the stay damper urged in the direction, the cylinder body has a small-diameter portion near the end to reduce the inner diameter, and a stopper member fixed to the rod body and an outer periphery of the rod body are provided on the outer periphery of the rod body. A check seal that slides and a spring interposed between the stopper member and the check seal to urge the check seal toward the piston portion are provided, and the outer periphery of the rod body bypasses the check seal and performs a check. A bypass path closed to the maximum extension position by the seal is formed, and the outer peripheral lid of the check seal is contracted when the rod body is retracted from the maximum extension position in the cylinder body. The part is brought into close contact with the inner periphery of the small diameter part, and the contraction operation of the rod body is temporarily blocked. When a large external force is applied to the rod body to contract it, the check seal opens the bypass passage and closes the inner periphery of the small diameter part. A two-stage operation stay damper characterized by moving along with a rod body while sliding.