JPS644774Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to an improvement of an oil-filled shock absorber for elevators.

Elevators employ a number of electrical and mechanical safety devices to stop the elevator car before it reaches dangerous overspeed. Even if these safety devices do not work for some reason and the car passes the bottom floor and descends, shock absorbers are installed to support the car, alleviate collisions, and bring it to a safe stop. . Furthermore, the car does not stop even when it passes the top floor, and when it rises further, the counterweight is supported by a shock absorber installed directly below it. As the shock absorber, an oil-filled shock absorber is used for elevators with a car whose rated speed exceeds 60 m/min.

A conventional oil-filled shock absorber will be explained with reference to FIG. In Fig. 1, 1 is an elevator hoistway;
2 is a cylinder erected at the bottom 1a of the hoistway 1; 3 is a control rod erected at the bottom of the cylinder 2 and tapered so that the upper part gradually becomes narrower; 4
5 is a cylindrical plunger which is fitted into the cylinder 2 so as to be movable up and down and has an orifice 4a in its lower surface into which the control rod 3 is loosely inserted; 5 is a cap fixed to the upper end of the plunger 4; and 6 is the cylinder 1. A bush 7 is press-fitted to the upper end and through which the plunger 4 can slide, 7 is a fixing pin, and these pins 7 are drilled into the cylinder 2 and the bush 6 after the bush 6 is press-fitted into the cylinder 2. It's driven in. A spring seat 8 is fixed to a portion of the tip of the controller 3 protruding from the orifice 4a with a bolt 10, and a spring seat 9 is fitted into the hollow part of the plunger 4 and is interposed between the spring seat 8 and the cap 5. A return spring 11 that urges the plunger 4 toward the extraction side with respect to the cylinder 2 is oil filled in the cylinder 2.

Since the conventional oil-filled shock absorber for elevators was constructed as described above, the diameter of the plunger 4 had to be increased in order to make it easier to attach the spring seat 8 to the tip of the control rod 3 with the bolt 10. Also,
Hole 7a for inserting pin 7 for fixing bush 6 to cylinder 2 after inserting bush 6 into cylinder 2
Therefore, the wall thickness of the bush 6 must be made thick so that the hole 7a does not pass through the bush 6. For this reason, the diameter of the cylinder 2 must also be made considerably larger than the diameter of the plunger 4, and the oil-filled The disadvantage was that the buffer became larger.

Furthermore, as shown in Japanese Patent No. 144622, a plunger in which a return spring is disposed on the outer circumferential side is also known, but the diameter of the return spring is too small in relation to the spring force. Furthermore, since the return spring is supported on a thick pusher, the diameter of the cylinder cannot be made very small even if the return spring is provided on the outer circumferential side of the plunger.

This invention was made in order to eliminate the drawbacks of the conventional ones mentioned above, and its purpose is to improve the mounting structure between the plunger and cylinder and to make the oil-filled shock absorber for elevators more compact. be.

An embodiment of this invention will be described below with reference to FIG. In FIG. 2, the same reference numerals as in FIG. 1 indicate the same parts, and 12 is a threaded bushing. This threaded bushing 12 is screwed and fixed to the outer periphery of the upper end of the cylinder 2, and the plunger 4 slides through a hole in the center. We will guide you if possible. Reference numeral 13 denotes a holding pipe, and this pipe 13 is provided between the threaded bushing 12 and the bushing 6 which is fitted into the upper end of the cylinder 2 and whose lower surface is supported by a step provided on the inner peripheral surface of the cylinder 2. and press down on the bushing 6 to secure it. Further, the return spring 9 is disposed on the outer peripheral side of the plunger 4 and is interposed between the cap 5 and the upper end surface of the screw bush 12, and the lower end of the return spring 9 is integrally attached to the upper end surface of the screw bush 12. It is fitted into the formed protrusion. Note that in the embodiment shown in FIG. 2, the configuration other than those described above is the same as that of the conventional example shown in FIG. 1, so the explanation will be omitted.

In the oil-filled shock absorber constructed as described above, the diameter of the plunger 4 can be reduced, and the thickness of the bush 6 can also be made thinner because it does not need to be fixed with a pin 7 as in conventional ones, and the diameter of the cylinder 2 can be reduced. Also, the diameter of the plunger 4 can be made smaller than that of the conventional one. Furthermore, regarding the structure, since the spring seat 8 that was conventionally provided inside the plunger 4 is eliminated, the efficiency of assembly work can be improved.

As explained above, in the oil-filled shock absorber for an elevator of this invention, a screw bush 12 that presses the bush 6 in the cylinder 2 is screwed and fixed to the upper end of the cylinder 2, and a projection provided on the upper end surface of the screw bush 12 is provided. By fitting and supporting the lower end of the return screw 9 into the screw bushing 12, and by slidably fitting the plunger 4 into the hole in the center of the screw bushing 12, the fixing pin can be attached to the outer periphery of the cylinder, unlike conventional ones. Since it is not necessary to insert the bushing 6 in the radial direction from the side, the thickness of the bushing 6 inside the cylinder 2 can be made thinner, and the cylinder 2 can be made smaller in diameter.In addition, a projection is provided on the upper end surface of the threaded bush 12, and the threaded bushing 12 can be returned to the projection. Since the lower end of the spring is fitted, there is no need for a spring seat to prevent the spring from displacing in the radial direction, reducing the number of parts. Since it is,
The shape of the bush 6 inside the cylinder 2 can be simplified,
Coupled with the fact that the threaded bushing 12 also serves as a press for the bushing 6 in the cylinder 2, the structure is simple and assembly time can be reduced, making it possible to reduce the size and weight of the oil-filled shock absorber for elevators and to use materials. expenses,
This has the effect of reducing processing costs.

[Brief explanation of drawings]

Fig. 1 is a vertical cross-sectional view showing a conventional oil-filled shock absorber;
FIG. 2 is a longitudinal sectional view showing an oil-filled shock absorber according to an embodiment of this invention. 1...Hoistway, 1a...Bottom of the hoistway, 2...Cylinder, 4...Plunger, 6...Button, 9
...Returning spring, 12...Screw bush, 13...
…pipe. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Scope of utility model registration request] A cylinder 2 erected at the bottom 1a of the hoistway 1, and a bush 6 fitted and supported at the upper end of the cylinder 2.
an elevator oil comprising: a plunger 4 slidably penetrating the center of a bush 6 and fitted into the cylinder 2; and a return spring 9 urging the plunger 4 toward the extraction side with respect to the cylinder 2. In the shock absorber, a screw bush 12 that presses the bush 6 in the cylinder 2 is screwed and fixed to the upper end of the cylinder 2, and the lower end of the return spring 9 is attached to a protrusion provided at the center of the upper end surface of the screw bush 12. is fitted to support the return spring 9 on the upper end surface of the threaded bush 12, and a guide hole is formed in the center of the protrusion to penetrate into the cylinder and guide the sliding movement of the plunger 4. An oil-filled shock absorber for an elevator, characterized in that a plunger 4 is slidably fitted into the hole.