JPH0687742U - gas spring - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a gas spring that can safely maintain its state even when the fluid pressure in the tube cylinder is lowered in the most extended state. [Structure] An engagement pin (10) projecting from a piston rod (5) in the tube cylinder (1) and an engagement pin (10) disposed in the tube cylinder (1) at the time of maximum extension.
And a piston (4) having a vertical groove (9) into which is introduced and a locking groove (9A) notched in the circumferential direction from the vertical groove (9).
A gas spring comprising a stopper member (8) with which the abutting member abuts, and means (3) for rotatably supporting the tube cylinder (1) around a piston (4) and a piston rod (5).

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas spring, and more particularly, to a gas spring in which a reaction force of the gas spring maintains a state of maximum extension.

[0002]

[Prior art]

 As a conventional gas spring of this type, there is, for example, the one disclosed in FIG. 2 of Japanese Utility Model Laid-Open No. 4-56939. This conventional example is mounted on a back door of an automobile, and a cylinder is filled with gas and oil, and is defined by the piston member along with the movement of the piston member in the cylinder as the door is pulled up. First, the gas moves between the chambers, and then the oil moves, so that the piston member operates in the gas near the fully opened state of the door, that is, the most extended state of the gas spring. Incidentally, in the conventional gas spring of this type, which holds the door which is the opened / closed object in the fully opened state, the repulsive force of the compressed gas is the main.

[0003]

[Problems to be solved by the device]

 However, in the case where the open / closed object can be maintained in the fully open state only by the reaction force of the gas spring itself as in the above-mentioned conventional example, the gas enclosed in the cylinder may leak during long-term use. The reaction force decreases, and the force supporting the open / close object decreases.

The object of the present invention is to pay attention to such a conventional problem, and in order to solve the problem, it is possible to safely maintain even when the filling fluid pressure such as the gas pressure in the tube cylinder is reduced in the fully extended state. To provide a possible gas spring.

[0005]

[Means for Solving the Problems]

 In order to achieve such an object, the present invention provides an engagement pin projecting from a piston rod in a tube cylinder, a vertical groove arranged in the tube cylinder and into which the aforementioned engagement pin is introduced at the time of maximum extension, A stopper member having a locking groove notched in the circumferential direction from the vertical groove and contacting the piston at the time of the maximum extension, the piston rod in the tube cylinder, or the tube cylinder in the piston rod. And a means for rotatably supporting the engaging pin so that the engaging pin is guided from the vertical groove to the locking groove by rotating the piston rod or the tube cylinder at the time of the maximum extension. Is characterized by.

[0006]

[Action]

 According to the present invention, the engaging pin is guided to the vertical groove of the stopper member when fully extended, and the engaging pin is engaged with the vertical groove by rotating the piston rod or the tube cylinder. Since it can be guided to the stop groove, even if the reaction force is reduced, the operation in the compression direction can be stopped by the engagement of the engagement pin in the engagement groove.

[0007]

【Example】

 Embodiments of the present invention will be specifically described below with reference to the drawings.

FIG. 1 shows an embodiment of the present invention. Here, 1 is a tube cylinder whose one end is sealed by a plug member 2, in which high pressure gas and oil are sealed. The plug member 2 of this embodiment is fixed to the end of the tube cylinder 1 by press fitting, welding, etc., and its shaft portion 2A is rotatably fitted in the support hole 3A of the fixing bracket 3 and fixed. As shown in FIG. 2, the bracket 3 for use with the tube cylinder 1 is configured to allow rotation of the plug member 2 by an angle α °. In FIG. 2, 2B is an engagement pin projecting from the plug member 2 side toward the flange portion 3C side of the bracket 3, and 3B is formed by notching in the flange portion 3C of the fixing bracket 3, and the engagement pin 2B This is a restriction groove that restricts movement in the direction of movement within the range of angle α °.

Returning to FIG. 1, 4 is a piston member that moves while defining the inside of the tube cylinder 1 into two chambers 1A and 1B, 5 is a piston rod, and 6 and 7 are piston rods 5 of the tube cylinder 1 that penetrate. It is an oil seal and a guide member that are provided at the end on the side where it is closed. Here, FIG. 1 shows the most extended state of the gas spring, and 8 is a stopper member with which the piston member 4 abuts when fully extended. As shown in FIG. 3, the stopper member 8 is formed in a hollow cylindrical shape, and a vertical groove 9 is provided in the direction along the piston rod 5 from the side where the piston member 4 contacts. The stopper member 8 is fixed to the tube cylinder 1 by caulking 1C as shown in FIG.

Thus, at the time of normal expansion and contraction operation of the gas spring, the pin 10 protruding from the piston rod 5 in the radial direction is kept movably along the vertical groove 9 at the time of the maximum extension, and the vertical direction of the vertical groove 9 is also increased. A locking groove 9A that is cut out in the circumferential direction is formed on the bottom of the cylinder tube 1. By manually turning the cylinder tube 1 in the counterclockwise direction shown by the arrow in the most extended state shown in FIG. As shown in, the pin 10 can be introduced into the region of the locking groove 9A to restrain or restrict the operation in the compression direction. Further, the side of the vertical groove 9 on which the piston member 4 abuts is formed with a wide opening 9B so that the pin 10 provided on the piston rod 5 can be easily introduced into the vertical groove 9 at the time of maximum extension. Reference numeral 11 is a bracket attached to the other end of the piston rod 5, and is connected to the open / close object side via a pin (not shown).

Next, the operation of the gas spring thus configured will be described.

For example, the piston member 4 moves in the tube cylinder 1 with the opening operation from the most compressed state of the gas spring in which an open / close object such as a back door is kept in a closed state, and is pressed into the cylinder 1. The gas and oil that are present move from the chamber 1B to the chamber 1A via the communication passage 4A provided in the piston member 4, and then the two chambers are shut off by means not shown. The pin 10 provided on the piston rod 5 is guided into the vertical groove 9 of the stopper member 8 through the opening 9B before reaching the most extended state. Then, in the most extended state of FIG. 1 in which the piston member 4 contacts the stopper member 8, the pin 10 is located near the locking groove 9A formed in the vertical groove 9 of the stopper member 8.

Therefore, in such an extended state, the pin 10 is guided to the locking groove 9A as shown in FIG. 4 by rotating the tube cylinder 1 in the counterclockwise direction shown by the arrow in FIG. Even if there is a decrease in reaction force due to leakage of the enclosed gas, the operation of the gas spring in the compression direction can be restricted by locking the pin 10 in the locking groove 9A as shown in FIG. It is possible to prevent the door from closing due to its own weight due to the weakened reaction force of the gas spring.

In this embodiment, the locking groove 9A is provided from the bottom of the vertical groove 9 in the vertical direction along one circumferential direction, but the direction of formation is on either side in the circumferential direction. Alternatively, it may be formed bidirectionally. The point is that the pin 10 can be guided to the region of the locking groove by rotating the tube cylinder 1 in either direction in the most extended state so that the operation in the compression direction is restricted. Further, the space between the piston rod 5 and the bracket 11 may be rotatably supported.

[0015]

[Effect of device]

 As described above, according to the present invention, the engagement pin protruding from the piston rod in the tube cylinder and the vertical groove provided in the tube cylinder and into which the engagement pin is introduced at the time of maximum extension are provided. And a stopper member having a locking groove notched in the circumferential direction from the vertical groove and with which the piston abuts at the time of the maximum extension, the piston rod in the tube cylinder, or the tube cylinder in the piston rod. And a means for supporting the engaging pin so as to be rotatable around the shaft, and by rotating the piston rod or the tube cylinder at the time of the maximum extension, the engaging pin is guided from the vertical groove to the locking groove. The reaction force decreases due to leakage of the press-fitting fluid such as gas, and the holding force in the most expanded state is weakened, or a shock is applied in the compression direction via the opening / closing object. Even if the Unako, Ru can be safely maintained most extended state.

In addition, since the locking means for maintaining the most extended state is provided inside the tube cylinder, there is no protruding portion outside the cylinder, so that there is no obstruction or expansion or obstruction of the expansion / contraction operation. The configuration is simple and there is no fear of increasing costs.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example of the configuration of the present invention in a fully expanded state.

FIG. 2 is a sectional view taken along the line AA of FIG.

FIG. 3 is a sectional view taken along line BB of FIG.

FIG. 4 is an explanatory view showing a locking operation at the maximum extension according to the present invention.

FIG. 5 is an explanatory view showing a locked state when the reaction force is reduced at the maximum extension according to the present invention.

[Explanation of symbols]

 1 Tube Cylinder 1A, 1B Chamber 2 Plug Member 3,11 Bracket 4 Piston Member 5 Piston Rod 8 Stopper Member 9 Vertical Groove 9A Locking Groove 9B Opening 10 Pin

Claims (1)

[Scope of utility model registration request] 1. An engagement pin projecting from a piston rod in a tube cylinder, a vertical groove provided in the tube cylinder, into which the engagement pin is introduced at the time of maximum extension, and a notch circumferentially from the vertical groove. A stopper member having a locking groove formed therein, with which the piston comes into contact at the time of the maximum extension; and means for supporting the piston rod in the tube cylinder or rotatably supporting the tube cylinder around the piston rod. The gas spring is characterized in that the engagement pin is guided from the vertical groove to the locking groove by rotating the piston rod or the tube cylinder at the time of the maximum extension.