GUIDE RAIL FOR ELEVATOR

Abstract

 It is an object to obtain an elevator guide rail for which a required amount of material is decreased while ensuring a desired strength, in other words, an elevator guide rail that requires a small amount of material with respect to the strength.
In order to achieve the object, a guide rail is formed in an approximate T-shape, configured with a platelike base portion and a rail portion rising therefrom, and formed so that the rail portion is engaged with a guide unit to guide up-and-down movement of an elevator car or its counterweight, a recess is formed in the midportion of the bottom side of the base portion, and the cross-sectional area of the recessed portion is redistributed to both edges of the base portion and the top of the rail portion.

Description

TECHNICAL FIELD

[0001] The present invention relates to elevator guide rails for guiding within an elevator hoistway up-and-down movement of the elevator car as well as the elevator counterweight.

BACKGROUND ART

[0002] An elevator is so configured that an elevator car and its counterweight suspended via the main rope within a hoistway vertically travel in a jig-back way. The elevator car and the counterweight are guided by guide rails. The guide rails are laid across the vertical travel paths via rail supporting members at a predetermined spacing on inside walls of the hoistway. As a conventional guide rail, a T-shaped rail defined in ISO standard or Japan Elevator Association Standard is used, which is formed in an approximate T-shape in which a rail portion rises from a platelike base portion. The base portion is mounted on the rail supporting members, and the elevator car and the counterweight are guided on the rail portion. (e.g., see Patent Document 1).

[0003] Patent Document 1: Japanese Laid-open Patent Publication 238045/2003 (Pages 3 and 4, and Figs. 1 and 2)

DISCLOSURE OF THE INVENTION

[Problem that the Invention is to Solve]

[0004] A guide rail, which guides an elevator car and a counterweight as described above, is subject to load from the elevator car or the counterweight by an earthquake or emergency stop. Therefore, the strength against the load is required. In addition, because the guide rails are laid across the vertical travel paths, the longer the vertical travel paths, the more a required amount of guide rail per elevator car. Moreover, as the capacity of the elevator car increases, the guide rail size also increases. For those reasons, for an elevator, guide rails in which the required amount of material is decreased while ensuring a desired strength, in other words, guide rails that require a small amount of material with respect to the strength are desired.

[0005] The present invention has been made to resolve such problems, and aims to achieve guide rails in which a required amount of material is decreased while ensuring a desired strength, in other words, guide rails that require a small amount of material with respect to the strength.

[Means for Solving the Problem]

[0006] An elevator guide rail relevant to the present invention is formed in an approximate T-shape composed of a platelike base portion and a rail portion rising therefrom, and formed so that the rail portion is engaged with a guide unit to guide up-and-down movement of an elevator car or its counterweight, and a recess is formed in the midportion of the bottom side of the base portion.

[Effects of the Invention]

[0007] According to the present invention, by redistributing from a recessed portion in the midportion of the bottom side of the base portion to both edges of the base portion and ,the top of the rail portion, elevator guide rails in which the strength is increased while controlling the required amount of material can be obtained.

BRIEF DESCRIPTION OF DRAWINGS

[0008] 

[Fig. 1] Fig. 1 is a diagram illustrating a cross-sectional view of a guide rail in Embodiment 1 of the present invention.

[Fig. 2] Fig. 2 is a diagram illustrating an example in which the guide rails in Embodiment 1 are applied to an elevator.

[Fig. 3] Fig. 3 is a diagram illustrating comparison of the guide rail in Embodiment 1 with a conventional guide rail.

[Fig. 4] Fig. 4 is a diagram illustrating a state in which the guide rail in Embodiment 1 is used.

[Fig. 5] Fig. 5 is a diagram illustrating a guide rail in another embodiment of the present invention.

[Description of the Symbols]

[0009] 1: guide rail; 2: base portion; 2a: sloping surface; 2b: arc-section recess; 2c: rectangular-section recess; 3: rail portion; 3a: rail head portion; 3b: rail neck portion; 4: elevator car; 5: guide units; 6: rail brackets; 7: rail clips; 8: bolts; 9: screw nuts; 10: guide rollers

BEST MODE FOR CARRYING OUT THE INVENTION

[0010] Hereinafter, a preferred embodiment of the present invention will be described in reference to the drawings.

Embodiment 1.

[0011] Fig. 1 through Fig. 3 are diagrams illustrating Embodiment 1 of the present invention. Fig. 1 is a cross-sectional view of a guide rail in the present embodiment; Fig. 2 illustrates an example in which the guide rails are applied to an elevator; Fig. 3 is a diagram comparing the guide rail in the present embodiment with a conventional guide rail; and Fig. 4 is a diagram illustrating a state in which the guide rail in the present embodiment is used. In Fig. 1, the guide rail 1 is configured such that a rail portion 3 is formed upright from a platelike base portion 2, to exhibit an approximate T-shapo. Sloping surfaces 2a are formed on the top face of the base portion 2, and an arc-section recess 2b is formed in the midportion of the bottom side. A flat portion of the bottom side of the base portion is fixed to unillustrated rail brackets, and the rail brackets are fixed to inside walls of the hoistway at a predetermined spacing, whereby the guide rails 1 are laid along the hoistway. The rail portion 3 includes a.rail head portion 3a for engaging with an unillustrated guide unit, and the rail head portion 3a is connected to the base portion via a rail neck portion 3b that is slimmer than the rail head width. There portions are integrally formed, to constitute the guide rail 1.

[0012] Here, the load applied to the guide rail 1 will be described: Fig. 2 illustrates an example in which the guide rails 1 are applied to an elevator. Fig. 2 (a) illustrates a top view, and (b) illustrates a front view. The guide units 5 are attached to four corners of the elevator car 4. The guide units 5 are engaged with the guide rails 1, and guide to the guide rails 1 the elevator car 4 for traveling vertically. The guide rails 1 are fixed at a predetermined spacing via rail brackets 6 on the inside walls of the hoistway.

[0013] If an earthquake or the like occurs while the elevator car 4 is between fixed points of the guide rails 1, or between fixed points of the rail brackets 6, the seismic force thereof acts on the guide rails 1 via the guide units 5 as a force Fx in the apical direction of the rail head portion 3a and a force Fy in the lateral-side direction thereof. Thus, the guide rails 1 are subject to bending moments by two-directional forces Fx and Fy due to an earthquake between the fixed points thereof, so that the guide rails require a desired strength against the bending moments.

[0014] Next, comparison of the guide rail 1 according to the present embodiment with a conventional guide rail will be described. Fig. 3 illustrates comparison with a conventional ISO-standard T-shaped rail, for example. Compared with the conventional ISO-standard T-shaped rail, the guide rail 1 according to the present embodiment is formed so that a recess 2b is formed in the midportion of the bottom side of the base portion 2, and the recessed portion in the midportion of the bottom side of the base portion 2 is redistributed to both edges of the base portion 2 and to the top of the rail head portion 3a so that the figure center A of the cross section is approximately the same position. In addition, the guide rail is formed so that the height H1 of the edge faces of the base portion 2 and the gradient angle of the sloping surface 2a of the base portion 2 are the same as those of the ISO-standard T-shaped rail, and the width B of the rail head portion 3a and the height H2 of the rail head portion 3a are the same as those of the ISO-standard T-shaped rail.

[0015] As described above; while the guide rail 1 according to the present embodiment has the same sectional area as the conventional ISO-standard T-shaped rail, by forming the recess 2b in the midportion of the base portion 2, the occupied area nearer to the figure center A of the cross section is decreased, and the recessed portion is redistributed to portions distant from the figure center A of the cross section (to both edges of the base portion 2 and the top of the rail head portion 3a), whereby the geometrical moment of inertia can be increased, and the section modulus can be increased as well. Accordingly, using the same required amount of material as the conventional ISO-standard T-shaped rail, the strength against bending moments in two directions (horizontal and vertical directions in Fig. 3) can be increased.

[0016] In addition, to the contrary, when a guide rail is formed so that the midportion of the bottom side of the base portion 2 is formed in a recessed form as described above so as to have the same geometrical moment of inertia as the conventional ISO-standard T-shaped rail, the cross-sectional area can be decreased, and the required amount of material can be reduced.

[0017] Next, an example in which the guide rail 1 according to the present embodiment is used will be described. Fig. 4 illustrates the example of use. Rail clips 7 are fixed to a rail bracket 10 by the sloping surface 2a of the base portion 2 being fastened with bolts 8 and screw nuts 9, whereby the guide rail 1 is fixed to the rail bracket 10. Then, guide rollers 11 serving as a guide unit are engaged with both the side faces and the edge of the rail head portion 3a. The guide rollers guide up-and-down movement of an unillustrated elevator car or counterweight equipped with a guide unit.

[0018] As described above, the guide rail 1 is the same as a conventional ISO-standard T-shaped rail in the height of the edge faces of the base portion 2, the gradient angle of the sloping surface 2a of the base portion 2, the width of the rail head portion 3a, and the height of the rail head portion 3a. Therefore, regarding the rail clips 7 for fixing the guide rail 1 and the guide rollers 10 serving as a guide unit, existing conventional parts can be used. Accordingly, without using new parts, the guide rail 1 of high strength, for which a required amount of material is small, can be applied to an elevator, which is economical.

[0019] It should be noted that, although in the present embodiment an arc-section recess 2b is formed in the midportion of the base portion 2, it is not so limited. For example, a rectangular-section recess 2c can be formed in the midportion of the base portion 2 as in Fig. 5. However, an arc-section recess is more effective, because the smaller the area of components close to the figure center of the cross section and the larger the area of components distant from the figure center, the greater the geometrical moment of inertia with the same required amount of material.

INDUSTRIAL APPLICABILITY

[0020] As described above, an elevator guide rail 1 relevant to the present invention is suitable to be used for apparatuses guiding up-and-down movement of an elevator car or its counterweight along a hoistway.

Claims

1. An elevator guide rail formed in an approximate T-shape, comprising a platelike base portion and a rail portion rising therefrom, the rail portion being engaged with a guide unit to guide up-and-down movement of an elevator car or counterweight, and the midportion of the bottom side of the base portion being recessed.

2. An elevator guide rail according to claim 1, characterized in that the recess in the midportion of the bottom side of the base portion is formed to have an arc contour.

3. An elevator guide rail according to claim 1 or claim 2, characterized in that
the elevator guide rail exhibits a form which is that of the ISO or Japan Elevator Association standard for T-shaped rails;
the width of the rail portion where it engages with the guide unit, the height of both edge faces of the base portion, and the gradient angle of sloping surfaces formed from both edges of the base portion toward the rail portion are identical with the standard; and
the cross-sectional area of the recessed portion in the midportion of the bottom side of the base portion is redistributed to the top of the rail portion and both the edges of the base portion.

Drawing