JP5452327B2 - Shock absorber for elevator - Google Patents

Description

  The present invention relates to an impact shock absorber for an elevator, which is installed at the bottom of an elevator hoistway and is used to alleviate an impact and stop safely when a car or a counterweight descends after passing over the lowest floor. .

  Conventionally, a cylinder attached to the pit bottom of the elevator hoistway so as to protrude upward, a plunger protruding upward from the upper end of the cylinder and extending and contracting in the axial direction with respect to the cylinder, and a top of the cylinder. A switch mounting arm that protrudes laterally, a plunger return confirmation switch that is mounted at the tip of this switch mounting arm, and a cam that protrudes and mounts on the top of the plunger in the same direction as the switch mounting arm 2. Description of the Related Art There is known an elevator shock absorbing device that includes a mounting arm and a rod-shaped switch cam that is vertically extended and attached to the tip of the cam mounting arm (see, for example, Patent Document 1).

In this elevator shock absorber, when the car or the counterweight is lowered for some reason and pushes down the plunger, the switch cam turns off the plunger return confirmation switch and the power is shut off. Stops safely while being buffered by the resistance of hydraulic oil.
Thereafter, the load on the plunger is removed when the car or the counterweight rises and returns to the steady position, so that it slides upward by the action of the helical spring in the plunger and returns to the original position.
At the same time, the switch cam also returns to the original position, and the plunger return confirmation switch is turned ON.

If the plunger does not return completely to the original position, the switch cam does not turn on the plunger return confirmation switch, and the power source remains cut off, so that the car is not operated.
Therefore, when the car or the counterweight falls for some reason and collides with the shock absorbing device, the stroke of the plunger for safely stopping the car or the counterweight can always be maintained.

Japanese Patent Laid-Open No. 2004-10327 (FIG. 10)

  However, in this case, since the helical spring generates a torsional stress when the plunger is pushed down and returned, the plunger moves downward while moving in the circumferential direction around the shaft center, and also moves upward. The relative position of the plunger return confirmation switch and the switch cam in the circumferential direction is shifted, and the plunger return confirmation switch does not operate normally.

  An object of the present invention is to solve the above-described problems, in which the displacement of the circumferential position of the switch cam with respect to the plunger return confirmation switch is prevented, and normal operation of the plunger return confirmation switch is prevented. It is an object to obtain an impact shock absorber for an elevator that is secured.

The elevator shock absorber according to the present invention includes a cylinder mounted to protrude upward at the pit bottom of the elevator hoistway, and protrudes upward from the upper end of the cylinder and along the axial direction with respect to the cylinder. And a plunger mounted on the top of the cylinder, a plunger return confirmation switch mounted on the switch mounting body, and a cam mounted on the top of the plunger so as to protrude from the plunger in the horizontal direction. A mounting arm, a rod-shaped switch cam that is attached to the end of the cam mounting arm and extends vertically downward to switch the plunger return confirmation switch, and a helical spring provided in the cylinder or the plunger And
After the elevator moves down the lower floor and collides with the plunger and pushes down the plunger, the elevator moves up and the load on the plunger is removed, and the plunger is stationary by the restoring force of the helical spring. When returning to the position, the switch cam also returns to the original position, and is an impact shock absorber for an elevator that switches the plunger return confirmation switch,
The switch mounting body is provided so as to surround a cylinder and is restricted from moving in the vertical direction with respect to the cylinder, and is capable of being displaced in the circumferential direction around an axis, and the switch cam is connected to the switch cam. And a cam guide provided around,
As the switch cam is displaced in the circumferential direction, the plunger return confirmation switch is also displaced in the circumferential direction together with the annular guide so as to face the switch cam.

  In the elevator shock absorber according to the present invention, the plunger return confirmation switch is also displaced in the circumferential direction together with the annular guide while facing the switch cam along with the circumferential displacement of the switch cam. The position shift is prevented, and the normal operation of the plunger return confirmation switch is ensured.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front view showing an elevator shock absorber according to Embodiment 1 of the present invention. FIG. 2 is a cross-sectional plan view of a main part of FIG. 1. It is a principal part perspective view of the shock absorber for elevators of FIG. It is an enlarged view of the site | part of the arrow A of FIG. It is a fragmentary sectional view of the site | part of the arrow B of FIG. It is a partial front view which shows the shock absorber for elevators of Embodiment 2 of this invention.

Embodiment 1 FIG.
1 is a front view showing an impact shock absorber for an elevator according to Embodiment 1 of the present invention, FIG. 2 is a sectional plan view of the main part of FIG. 1, and FIG. 3 is a perspective view of the main part of the impact shock absorber for elevator of FIG. 4 is an enlarged view showing a part indicated by an arrow A in FIG. 3, and a partial cross-sectional view showing a part indicated by an arrow B in FIG. 3 in FIG.
The impact shock absorber for an elevator includes a cylinder 1 attached so as to protrude upward from a pit bottom of an elevator hoistway, and protrudes upward from an upper end portion of the cylinder 1 and extends in an axial direction with respect to the cylinder 1. A plunger 2 that can be moved up and down, a switch mounting body 3 provided on the top of the cylinder 1, a plunger return confirmation switch (hereinafter abbreviated as a confirmation switch) 4 mounted on the switch mounting body 3, and a plunger. A cam mounting arm 5 which is attached to the top of 2 in a horizontal direction so as to protrude from the peripheral surface of the plunger 2, and a rod-shaped switch cam 6 which is attached to the tip of the cam mounting arm 5 so as to extend vertically downward. It has.
The confirmation switch 4 is connected with a control wire, but the control wire is not shown.

  1-3, the inside of the cylinder 1 is not shown, but a conical member is provided extending vertically from the bottom. This conical member faces the inside of the plunger 2 through a squirting hole formed at the bottom of the plunger 2. A helical spring that urges the plunger 2 upward is loosely inserted into the conical member. Further, the inside of the cylinder 1 is filled with hydraulic oil that reaches the inside of the plunger 2 through the oil jet holes.

The switch mounting body 3 includes a short piece portion 9a of an L-shaped restriction plate 9 which is fixed to a peripheral wall surface of the cylinder 1 with a screw 8 below the flange 7 of the cylinder 1, and a radial direction over the entire circumference. It is provided between the projecting flange 7, and the movement in the vertical direction is regulated by the flange 7 and the short piece portion 9 a of the regulation plate 9.
The annular guide 10 has a U-shaped cross section that is open in the radially outer direction, and shafts 11 are provided at equal intervals of 120 ° in the circumferential direction. Each shaft 11 is provided with a roller 12 that can roll on the peripheral surface of the cylinder 1. The roller 12 is, for example, nylon that is lightweight, does not rust, and is slippery.
The annular guide 10 is cut away at a portion facing the switch cam 6. This notch portion is applied to a switch mounting plate 14 fixed to the back surface with a screw 15.
A confirmation switch 4 is fixed to the switch mounting plate 14. A cam guide 13 surrounding the confirmation switch 4 and the switch cam 6 is fixed to the surface of the annular guide 10 with screws 16. The cam guide 13 is formed with a gap between both sides of the switch guide 6 in the circumferential direction and the opposite side of the confirmation switch 4.

In this elevator shock absorber, for example, the elevator car is lowered for some reason, the bottom surface of the elevator car collides with the receiving plate 18, and a push-down force acts on the plunger 2.
As a result, the hydraulic oil in the cylinder 1 is injected into the plunger 2 through the jet hole and the plunger 2 starts to descend.
At this time, a strong braking force acts on the plunger 2 due to the so-called orifice effect of the fountain hole, in which the hydraulic oil passes through the narrowed constriction gap between the inner wall surface of the fountain hole and the outer peripheral wall surface of the conical member. To do.
Since the conical member has a tapered shape, as the plunger 2 descends, the flow passage cross-sectional area of the throttle gap decreases, so that the braking force against the plunger 2 increases, and as a result, the descending speed of the car gradually decreases. And the car stops safely.

As the plunger 2 descends, the switch cam 6 also descends, but when the switch cam 6 begins to descend, the bent portion 6a formed at the tip of the switch cam 6 collides with the switch roller 17 of the confirmation switch 4, Due to the collision force, the switch cam 6 tries to rotate with the rotational force acting in the counterclockwise direction in FIG. 1, but this rotation is blocked by the cam guide 13.
Further, as the switch roller 17 rotates in the clockwise direction, the confirmation switch is turned off and the power supply is shut off.
Further, as the plunger 2 descends, a torsional stress of the helical spring in the cylinder 1 causes a circumferential displacement force to act on the plunger 2 around the axis, and the switch cam 6 is displaced in the circumferential direction together with the plunger 2. However, the displacement is transmitted to the annular guide 10 through the cam guide 13, the confirmation switch 4 follows the displacement in the circumferential direction of the switch cam 6, and the switch roller 17 always moves on the center line of the switch cam 6. .

Thereafter, when the car rises and returns to the steady position, the load on the plunger 2 is removed. Therefore, due to the elastic force of the helical spring in the cylinder 1, the plunger 2 moves upward and returns to the original position. Return.
Even when the plunger 2 is lifted, the torsional stress of the helical spring in the cylinder 1
A displacement force about the axis acts on the plunger 2, and even if the switch cam 6 is displaced in the circumferential direction together with the plunger 2, the displacement is transmitted to the annular guide 10 through the cam guide 13, and the confirmation switch 4 Following the circumferential displacement of the switch cam 6, the switch roller 17 always moves on the center line of the switch cam 6.
Therefore, at the same time when the plunger 2 returns to the original position, the switch roller 17 contacts the bent portion 6a of the switch cam 6 and turns on the confirmation switch.

  As described above, according to the elevator shock absorber of this embodiment, the confirmation switch 4 is also displaced in the circumferential direction together with the annular guide 10 so as to face the switch cam 6 as the switch cam 6 is displaced in the circumferential direction. Therefore, the displacement of the circumferential position of the switch cam 6 with respect to the confirmation switch 4 is prevented, and normal operation of the confirmation switch 4 is ensured.

Moreover, since the roller 12 which rolls on the surrounding wall surface of the cylinder 1 is rotatably provided in the annular guide 10, the annular guide 10 is smoothly displaced in the circumferential direction around the axis.
Moreover, since the plurality of rollers 12 are arranged at equal intervals in the circumferential direction, the annular guide 10 is displaced more smoothly with a small force in the circumferential direction around the axis.

  Further, since the annular guide 10 is provided with the cam guide 13 surrounding the switch cam 6, the switch cam 6 does not leave the switch roller 17.

Embodiment 2. FIG.
FIG. 6 is a front view of an essential part of an elevator shock absorber according to Embodiment 2 of the present invention.
In this embodiment, a reinforcing member 20 extending in the vertical direction is provided on one surface of the switch cam 6. The reinforcing member 20 has a maximum at the cam mounting arm 5 side and a narrow width along the tip side.
Other configurations are the same as those of the shock absorber for elevator according to the first embodiment.

In this embodiment, since the reinforcing member 20 extending in the vertical direction is provided on one surface of the switch cam 6, the rigidity of the switch cam 6 is improved.
In the case of a high-speed elevator, the total length of each of the cylinder 1 and the plunger 2 is several meters, and the total length of the switch cam 6 is increased accordingly.
When the reinforcing member 20 is not present, the entire length of the switch cam 6 is long, and a part of the pressing force whose tip end presses the switch roller 17 is consumed for the bending deformation of the switch cam 6 and is not easily transmitted to the switch roller 17 as it is. .
On the other hand, by providing the switch cam 6 with the reinforcing member 20, the pressing force of the switch cam 6 accompanying the downward movement of the plunger 2 is transmitted to the switch roller 17 as it is, and the normal operation of the confirmation switch 4 is ensured. The
Further, the reinforcing member 20 is wider at a portion where the bending moment with respect to the switch cam 6 is larger, and the weight of the reinforcing member 20 is minimized.
Note that the reinforcing material 20 may be provided on both surfaces of the switch cam 6.

In each of the above embodiments, the cylinder 1 is filled with hydraulic oil whose oil level reaches the inside of the plunger 2, and a helical spring that is compressed as the plunger 2 moves downward is housed. However, the present invention can also be applied to an impact shock absorber for an elevator in which hydraulic oil is filled in the cylinder and a helical spring is accommodated in the plunger.
The present invention can also be applied to a so-called spring-type elevator shock absorber.
Further, the present invention can naturally be applied to an impact shock absorber for an elevator that cushions an impact from a counterweight that is a lifting body.

  1 Cylinder, 2 Plunger, 3 Switch mounting body, 4 Plunger return confirmation switch, 5 Cam mounting arm, 6 Switch cam, 6a Bent part, 7 Flange, 8, 15, 16 Screw, 9 Restriction plate, 9a Short piece part, 10 Annular guide, 11 shaft, 12 roller, 13 cam guide, 14 switch mounting plate, 17 switch roller, 18 receiving plate, 20 reinforcing material.

Claims (5)

A cylinder mounted to protrude upward from the pit bottom of the elevator hoistway, a plunger protruding upward from the upper end of the cylinder and moving up and down along the axial direction with respect to the cylinder;
A switch mounting body provided at the top of the cylinder;
A plunger return confirmation switch mounted on the switch mounting body,
A cam mounting arm attached to the top of the plunger so as to protrude horizontally from the plunger;
A rod-shaped switch cam attached to the end of the cam mounting arm and extending vertically downward to switch the plunger return confirmation switch;
And a helical spring provided inside the cylinder or the plunger, and the elevator moves down the lowest floor, collides with the plunger and depresses the plunger, and then the elevator moves up and the plunger An elevator shock absorber that switches the plunger return confirmation switch when the plunger cam returns to the steady position by the restoring force of the helical spring and the switch cam also returns to the original position. ,
The switch mounting body is provided so as to surround a cylinder and is restricted from moving in the vertical direction with respect to the cylinder, and is capable of being displaced in the circumferential direction around an axis, and the switch cam is connected to the switch cam. And a cam guide provided around,
A shock absorber for an elevator in which the plunger return confirmation switch is also displaced in the circumferential direction together with the annular guide while facing the switch cam along with the displacement in the circumferential direction of the switch cam.   The elevator shock absorber according to claim 1, wherein a roller that rolls on a peripheral wall surface of the cylinder is rotatably provided in the annular guide.   The elevator shock absorber according to claim 2, wherein a plurality of the rollers are arranged at equal intervals in the circumferential direction.   The impact shock absorber for an elevator according to any one of claims 1 to 3, wherein the switch cam is provided with a reinforcing member extending in the vertical direction on at least one side.   The cylinder is filled with hydraulic oil whose oil level reaches the inside of the plunger, and the helical spring that is compressed as the plunger moves downward is housed. The shock absorber for elevators according to any one of claims 1 to 4.

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