JPH06271236A - Position detector for elevator car - Google Patents

Abstract

PURPOSE:To provide a position detector for an elevator car wherein no- maintenance for a long period and stable accuracy after operating an elevator are embodied by protecting a pulse generator from oil adhering to a guide rail. CONSTITUTION:Since a roller 3a of a pulse generating means 3 is provided between an upper part guide piece 5 set up in the upper part and a lower part guide piece 7 set up in the lower part, of an elevator cage 1, the roller 3a is rolled on a guide rail 2, where dust or the like is cleaned by the guide pieces 5, 7, to eliminate changing a roller diameter due to sticking the dust or the like, and since a rotational speed of the roller 3a is not changed, a high accurate pulse is generated. Thus by improving accuracy of detecting a position and a speed of the elevator car 1, control of high reliability of the elevator car 1 can be performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an elevator position detecting device for detecting the position of an elevator car, and more particularly to an elevator position detecting device having an encoder.

[0002]

2. Description of the Related Art As a technique relating to an elevator position detecting device which is provided in a conventional elevator car and detects the position of the elevator car, there is a technique described in JP-A-61-277573. A conventional position detecting device for an elevator car will be described.

FIG. 7 is an enlarged front view showing the configuration of the main part of the elevator position detecting device. In the figure, 50 is an elevator car, 51 is a guide rail provided in the hoistway to guide the elevator car 50, and 52 is a guide rail 51.
A roller 52a that abuts with a pulse generator 52b that has a pulse generator 52b that generates a pulse proportional to the amount of movement of the outer circumference of the roller 52a as main members; 53a is a mounting shaft of the pulse generating means 52; The pulse generating means 52 is axially supported by the frame body 53b, and a spring 53d whose pressing force is adjusted by an adjusting screw 53c is arranged between the pulse generating means 52 and the frame body 53b. That is, the mounting shaft 53a, the frame 53b, the adjusting screw 53c, the spring 5
The attaching means 53 of the pulse generating means 52 is constituted by 3d. The attachment means 53 is fixed to the upper portion of an upper guide 54 that engages with the guide rail 51 and guides the elevator car 50. A lower guide (not shown) is installed at the bottom of the elevator car 50. 55 is a signal transmission cable for transmitting the signal emitted from the pulse generating means 52.

The operation of the conventional elevator car position detecting device configured as described above will be described. Since the roller 52a of the pulse generating means 52 is rotatably attached about the attachment shaft 53a pivotally supported by the frame 53b,
The compression amount of the spring 53d that presses the pulse generating means 52 is adjusted by the adjusting screw 53c, and the roller 52a that is in contact with the guide rail 51 is kept in an elastic contact state so as not to run idle. In addition, the roller 52 pressed by the guide rail 51
Since a is accurately rotated in proportion to the amount of vertical movement of the elevator car 50, the pulse generator 52b coupled to the roller 52a generates a pulse signal proportional to the rotation of the roller 52a, and the amount of vertical movement of the elevator car 50 is increased. Outputs a pulse signal proportional to. This pulse signal is input to a central processing unit (not shown), and the phase rotation direction of a drive motor (not shown) is detected from the pulse signals having a phase difference to detect the ascending or descending direction of the elevator car 50. To do. Then, the pulse signal input to the central processing unit (not shown) is processed into an acceleration command, a deceleration command, etc. of the elevator car 50 by a calculation process to control the speed of the elevator car 50 and the traveling position of the elevator car 50. Is detected and signal control such as position display is performed.

[0005]

However, the position detecting device for the elevator car disclosed in the above publication has the elevator car 50 guided by the upper guide 54 and the lower guide.
However, in order to reduce the frictional resistance between the guide rail 51 and the upper guide element 54 and the lower guide element, the contact surface between the guide rail 51 and the upper guide element 54 and the lower guide element is lubricated. Is the upper guide 5 on the guide rail 51
4 and the lower guider are attached to the running surface.

As described above, in the conventional position detecting device attached to the elevator for supplying oil to the contact surfaces of the guide rail 51, the upper guide 54 and the lower guide, the roller 52a is mounted on the guide rail 51 to which oil is attached. Will roll around. Moreover, once dust, dust, etc. floating in the hoistway adheres to the oiled guide rail 51, the dust, dust, etc. are hardened by the oil and adhere to the guide rail 51. When the roller 52a rolls on this lump of dust or dust, the dust or dust adheres to the roller 52a, and the diameter of the roller 52a gradually increases. As the roller 52a becomes larger, the rotation speed of the pulse generating means 52 becomes smaller. That is, when dust or a mass of dust adheres to the roller 52a,
When no dust or the like is attached, the rotation speed of the pulse generating means 52 changes due to the difference in the diameter of the roller 52a. When the rotation speed of the pulse generating means 52 changes, the acceleration command and the deceleration command of the elevator controlled by the pulse signal change, the start and stop shocks of the elevator increase, and the traveling position changes, so the elevator stop position changes. Is crazy.

When the roller 52a rolls on the lubricated guide rail 51, the roller 52a is oiled, and the amount of oil adhering to the roller 52a is gradually increased, so that the roller 52a is increased.
Not only the rolling surface of a, but also the side surface of the oil will be dripping. If this oil is not removed, the oil will travel along the shaft connecting the pulse generating means 52 and the roller 52a, enter the inside of the pulse generating means 52, and cause the failure of the pulse generating means 52.

Therefore, it is an object of the present invention to provide a position detecting device for an elevator car, which reduces the amount of dust and the like adhering to the rollers, can be maintained for a long period of time, and can obtain stable accuracy after the elevator is operated. It is what

[0009]

According to a first aspect of the present invention, there is provided an elevator car position detecting device which is guided by a guide rail which is vertically fixed to a hoistway and which travels in the hoistway. Upper and lower guide elements that are engaged with rails and that are disposed on the upper and lower portions of the elevator car; and rollers that are disposed between these guide elements and that abut on the guide rails and rotate. The pulse generator is connected to the roller and generates a pulse proportional to the amount of movement of the outer circumference of the roller.

According to a second aspect of the present invention, there is provided an elevator car position detecting device which is guided by a guide rail which is erected and fixed in a hoistway, and which is connected to the rollers together with the elevator car traveling in the hoistway. Pulse generating means for generating a pulse proportional to the amount of movement of the roller, a roller rotating in contact with the guide rail, and a pulse generator connected to the roller for generating a pulse proportional to the amount of movement of the outer circumference of the roller. However, a rotating member is arranged between the roller and the pulse generator.

According to a third aspect of the present invention, there is provided an elevator car position detecting device which is guided by a guide rail which is vertically installed and fixed to a hoistway, and which is connected to the roller together with the elevator car traveling in the hoistway and the outer circumference of the roller. A pulse generator that generates a pulse proportional to the amount of movement of the roller, a roller that contacts the guide rail and rotates, and a pulse generator that is connected to the roller and that generates a pulse that is proportional to the amount of movement of the outer circumference of the roller. Then, a sheet made of a material that absorbs and holds oil is attached to the side surface of the roller.

According to a fourth aspect of the present invention, there is provided an elevator car position detecting device which is guided by a guide rail which is vertically erected in a hoistway and which is connected to the roller together with the elevator car traveling in the hoistway. A pulse generator that generates a pulse proportional to the amount of movement of the roller, a roller that contacts the guide rail and rotates, and a pulse generator that is connected to the roller and that generates a pulse that is proportional to the amount of movement of the outer circumference of the roller. Further, it further comprises a rotating member arranged between the roller and the pulse generator, and a sheet made of a material that is attached to the side surface of the rotating member and absorbs and holds oil. .

[0013]

According to the first aspect of the present invention, the rollers are arranged so as to contact the guide rails between the guides arranged at the upper part and the lower part of the elevator car. Therefore, each time the elevator car moves up and down, The guides installed in the upper and lower parts remove dust and dirt adhering to the guide rails, and the rollers roll on the guide rail surfaces cleaned by the upper and lower guides. No dust or dirt will adhere.

In the present invention, the rotating member is fixed to the shaft connecting the roller and the pulse generator so that the oil supplied to the rotating member is transmitted from the side surface of the roller to the pulse generator through the shaft. Acts as a baffle to cut off.
Also, the oil that is cut off by the rotating member adheres to the rotating member,
Since the rotary member is connected to the shaft of the roller, the elevator car is rotated by the up-and-down motion of the elevator car, and the centrifugal force thus obtained causes the oil adhering to the rotary member to be blown off and the oil not to be transmitted to the pulse generator.

According to a third aspect of the present invention, an oil adsorbing sheet made of a material that absorbs and absorbs oil is attached to the side surface of the roller, so that when the oil attached to the guide rail travels along the side surface of the roller. It is absorbed and held by the oil adsorption sheet. This can prevent the oil from being transmitted from the roller side surface to the shaft, and as a result, the oil can be prevented from entering the pulse generator. Further, the oil adsorption sheet can be replaced by reattaching it.

According to the present invention, the oil adsorbing sheet is attached to the flat surface of the rotating member provided on the shaft between the roller and the pulse generator, so that it cannot be removed by the centrifugal force due to the rotation of the roller, so The oil remaining on the member is absorbed and held by the sheet attached to the rotating member, and can be removed by replacing the oil adsorption sheet.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the position detecting device for an elevator car according to the present invention will be described below. <First Embodiment> A first embodiment of the position detecting apparatus for an elevator car according to the present invention will be described. 1, 2 and 3
1 shows an elevator position detecting device constituting a first embodiment of the present invention. FIG. 1 is an overall configuration diagram, FIG. 2 is an enlarged perspective view of an essential part, and FIG. 3 is an essential part taken along a section line XX. The expanded sectional view is shown.

In the figure, 1 is an elevator car, 2 is a guide rail for guiding the elevator car 1, 3 is a roller provided in the hoistway, and 3 is a roller 3a which is in contact with the guide rail 2.
The pulse generating means is composed of a pulse generator 3b that generates a pulse proportional to the amount of movement of the outer circumference of the roller 3a. A sliding piece 5a made of a low-wear material is inserted into the contact portion of the upper guide 5 with the guide rail 2. Reference numeral 6 is a signal transmission cable for transmitting the signal emitted from the pulse generating means. Reference numeral 7 denotes a lower guide fixed to the lower portion of the elevator car 1 and engaged with the guide rail 2. The lower guide 7 has the same low wear as the upper guide 5 inserted into the contact portion with the guide rail 2. A sliding piece (not shown) made of a flexible material (hereinafter, referred to as 7a for convenience, is structurally the same as the sliding piece 5a). Further, the roller 3 a of the pulse generating means 3 is arranged between the upper guide piece 5 and the lower guide piece 7, and is arranged so as to make elastic contact with the guide rail 2. 8 is a guide rail 2
An oil feeder that supplies lubricating oil for reducing frictional resistance between the upper and lower sliders and is attached to the upper portion of the upper guide element 5. 9 is a mounting base for mounting the upper guide 5 fixed to the upper frame 1a of the elevator car 1, 10 is a pin projectingly fixed to the mounting base 9 so as to keep a certain distance from the guide rail 2, and 11 is a pin 9. It is an attachment metal of the pulse generating means 3 which is rotatably supported, and has a through hole 11a for inserting a cylindrical connecting shaft 12 that connects the roller 3a and the pulse generator 3b. Reference numeral 13 is a weight fixed to the mounting metal 11 on the opposite side on which the pin 10 is arranged.

Next, the operation will be described. In the elevator car position detecting device configured as described above, the pressing force of the roller 3a that contacts the guide rail 2 is
a, the pulse generator 3b, the attachment metal 11, the weight of the coupling shaft 12 and the weight 13, and the roller 10a which is orthogonal to the pin 10 and is horizontal, the pulse generator 3b, the attachment metal 11, the coupling shaft 12 and the weight 13. It is obtained from the rotation moment about the pin 10 generated by the distance to the position of the center of gravity. Due to this pressing force and the frictional force generated between the roller 3a and the guide rail 2, the roller 3a does not run idle and the elevator car 1
The rotation amount of the roller 3a proportional to the amount of vertical movement of is transmitted to the pulse generator 3b via the connecting shaft 12.

The sliding pieces 5a and 7a fixed to the upper guide piece 5 and the lower guide piece 7 are kept in contact with each other in order to restrict the lateral movement of the elevator car 1. Further, the sliding pieces 5a and the sliding pieces 7a wipe off large dust or dust particles adhering to the guide rail 2 each time the elevator car 1 moves up and down. Therefore, the upper guide 5 and the lower guide 7
The traveling surface on the guide rail 2 located between the positions can maintain a relatively small amount of dust and dirt, and can also maintain a state without large dust and lumps of dust. Therefore, the roller 3a disposed between the upper guide piece 5 and the lower guide piece 7 and in contact with the guide rail 2 rolls on the running surface on the guide rail 2 which is small in dust and the like.

As described above, the position detecting device for the elevator car according to the present embodiment has the guide rails 2 fixed to the hoistway and the elevator car 1 guided by the guide rails 2 and traveling in the hoistway. And guides 5, 7 which are engaged with the guide rail 2 and are arranged in the upper and lower parts of the elevator car 1, and between the upper guide 5 and the lower guide 7, A roller 3a that abuts on the rail 2 and rotates, and a roller 3a that is linked to the roller 3a.
And a pulse generator 3b for generating a pulse proportional to the amount of movement of the outer circumference of the pulse generator 3b, which can be an embodiment of the invention of claim 1.

By the way, the upper guide piece 5 and the lower guide piece 7 for carrying out the present invention are not necessarily provided with a sliding piece 5a made of a low-wear material at the contact portion with the guide rail 2. It is not necessary that the guide rail 2 be held in a low friction state and the close contact state be maintained.

<Second Embodiment> FIG. 4 is an explanatory view showing a second embodiment of the present invention, which is a cutting line X- of the first embodiment of the present invention.
It is an equivalent view of a cross-sectional view by X. In the drawings, the same reference numerals and symbols as those in the first embodiment show the same or corresponding components as those of the first embodiment, and therefore, duplicated description will be omitted here.

In the figure, reference numeral 20 is a rotating member which is located between the roller 3a and the pulse generator 3b and is fixed concentrically to the connecting shaft 12. Next, the operation of the position detecting device for the elevator car according to the second embodiment will be described. Lubricator 8
When the oil supplied from (see FIG. 2) to the guide rail 2 reaches the connecting shaft 12 along the side surface of the roller 3a pressed by the guide rail 2 and advances toward the pulse generating means 3, the oil is transferred to the roller 3a. Is blocked by the rotary member 20 fixed on the connecting shaft 12 of the pulse generator 3b. When the elevator car 1 moves up and down, the roller 3a rotates in accordance with the movement of the elevator car 1, and the connecting shaft 12 also rotates. At this time, since the rotary member 20 fixed to the connecting shaft 12 also rotates, the oil blocked by the rotary member 20 is scattered by the centrifugal force and does not reach the pulse generator 3b.

As described above, the position detecting device for the elevator car according to the present embodiment has the guide rail 2 fixed to the hoistway and the elevator car 1 guided by the guide rail 2 and traveling in the hoistway. A pulse generator 3b that is connected to the roller 3a to generate a pulse proportional to the amount of movement of the outer circumference of the roller 3a; a roller 3a that rotates by contacting the guide rail 2; The rotary member 20 is provided between the rotary member 20 and the container 3b, and this can be an embodiment of the invention of claim 2.

<Third Embodiment> FIG. 5 is an explanatory view showing a third embodiment of the present invention, which is a cutting line X- of the first embodiment of the present invention.
It is an equivalent view of a cross-sectional view by X. In the drawings, the same reference numerals and symbols as those in the first embodiment show the same or corresponding components as those of the first embodiment, and therefore, duplicated description will be omitted here.

In the figure, 30 is an oil adsorption sheet attached to the side surface of the roller 3a on the pulse generator 3b side,
It is composed of felt and porous fibers. Further, the oil adsorbing sheet 30 is coated on one side with an adhesive that can be easily peeled off, and has a structure that can be easily attached and detached.

Next, the operation of the oil adsorption sheet 30 will be described. When the oil supplied from the oil supply device 8 to the guide rail 2 reaches the side surface of the roller 3a pressed by the guide rail 2, the oil is absorbed and held by the oil adsorption sheet 30 attached to the side surface of the roller 3a, and Pulse generator 3b
The oil does not reach the connecting shaft 12 connecting the. Therefore, oil does not enter the pulse generator 3b. Further, since the oil adsorption sheet 30 is configured to be detachable, the oil adsorption sheet 30
If the oil adsorbing sheet 30 is replaced before the oil holding capacity is exceeded, it is possible to completely prevent the oil from moving from the roller 3a to the pulse generator 3b.

As described above, the position detecting device for the elevator car according to the present embodiment is provided with the guide rail 2 which is vertically installed and fixed in the hoistway, and the elevator car 1 which is guided by the guide rail 2 and travels in the hoistway. A roller 3a which contacts the guide rail 2 to rotate, a pulse generator 3b which is connected to the roller 3a and generates a pulse proportional to the amount of movement of the outer periphery of the roller 3a, and a side surface of the roller 3a. It is provided with an oil adsorbing sheet 30 made of a material that absorbs and holds oil, and this can be an embodiment of the invention of claim 3.

<Fourth Embodiment> FIG. 6 is an explanatory view showing a fourth embodiment of the present invention, which is a cutting line X- of the first embodiment of the present invention.
It is an equivalent view of a cross-sectional view by X. In the drawings, the same reference numerals and symbols as those in the first embodiment show the same or corresponding components as those of the first embodiment, and therefore, duplicated description will be omitted here.

In the figure, reference numeral 40 is an oil adsorbing sheet attached to the side surface of the rotary member 20 on the side of the pulse generator 3b, which is made of felt or porous fiber. Further, the oil adsorbing sheet 40 is coated with an adhesive that can be easily peeled off on one side, and has a structure that can be easily attached and detached. Next, the operation of the rotating member 20 and the oil adsorption sheet 40 will be described. The oil attached on the guide rail 2 reaches the rotating member 20 via the connecting shaft 12, and most of the oil is removed by the centrifugal force of the rotating member 20. The remaining oil is absorbed and held by the oil adsorbing sheet 40 attached to the pulse generator 3b side of the rotating member 20 when the elevator car 1 is stopped, so that even when the elevator car 1 is stopped. The oil can be prevented from being transmitted to the pulse generator 3b. The oil adsorbing sheet 40 of the fourth embodiment of the present invention is adhered to the pulse generator 3b side, but the same effect can be obtained by adhering it to the opposite side of the pulse generator 3b. You can But in this case,
The amount of oil adsorbed on the oil adsorbing sheet 40 increases, and the replacement timing becomes shorter.

As described above, the position detecting device for the elevator car according to the present embodiment has the guide rails 2 fixed to the hoistway and the elevator car 1 guided by the guide rails 2 and traveling in the hoistway. A roller 3a that contacts the guide rail 2 and rotates; a pulse generator 3b that is connected to the roller 3a and generates a pulse proportional to the amount of movement of the outer circumference of the roller 3a; and the roller 3a and the pulse generator. The rotating member 20 disposed between the rotating member 20 and the container 3b, and an oil adsorbing sheet 40 made of a material that absorbs and retains an oil component and is attached to a side surface of the rotating member 20. It can be an embodiment of the invention.

Although the rotating member 20 of the second and fourth embodiments of the present invention has a disc shape, its outer circumference is bent in the opposite direction to the pulse generator 3b side, or the pulse is generated. By bending so that the generator 3b is built in, the movement of oil can be interrupted. In particular, in the case where the pulse generator 3b is bent so as to be built in, the breaking efficiency can be increased. In each of the above embodiments, the pressing force for contacting the roller 3a of the pulse generator 3 with the guide rail 2 is determined by the gravity of the components of the pulse generator 3 and the weight 13 and the distance between the pin 10 and the center of gravity of the pin 10. Although it is obtained from the rotational moment generated, it is not always necessary to adopt this configuration, and for example, a spring as shown in the conventional example may be used to press the roller 3a.

[0034]

As described above, in the position detecting device for an elevator car according to the first aspect of the present invention, the rollers roll on the guide rails between the guides arranged on the upper and lower parts of the elevator car. Therefore, the roller rolls on the guide rail that has been cleaned of dust and dirt by the sliding piece of the guide element, and dust and dirt adhere to the contact surface of the roller with the guide rail. Since it is possible to eliminate the above problem and maintain a clean state at all times, the diameter does not change due to dust or dirt adhering to the roller. As a result, the rotation of the roller does not change, and a highly accurate pulse signal can be generated.
This highly accurate pulse signal improves the detection accuracy of the position and speed of the elevator and enables highly reliable elevator control.

In the elevator car position detecting device according to the second aspect of the present invention, since the rotating member is arranged in the connection between the pulse generator and the roller, the oil supplied to the guide rail is supplied to the pulse generator. The transmission is blocked, and the centrifugal force of the rotation of the rotating member associated with the lifting movement of the elevator car causes the oil to be scattered and removed. As a result, oil can be prevented from entering the pulse generator, and failure of the pulse generator due to oil intrusion can be eliminated.

In the elevator car position detecting device according to the third aspect of the present invention, the oil transmitted from the guide rail to the roller is adhered to the side surface of the roller on the pulse generator side by attaching an oil absorbing sheet for absorbing oil. Since it is absorbed and held by the oil suction sheet on the side surface of the roller, it is possible to prevent oil from entering the pulse generator. Further, by replacing the oil adsorbing sheet attached to the side surface of the roller before the oil holding capacity of the oil adsorbing sheet is exceeded, it is possible to prevent the oil from entering the pulse generator if the oil adsorbing sheet is replaced.

In the elevator car position detecting apparatus according to the invention of claim 4, the rotating member is attached to the rotating member disposed between the pulse generator and the roller, whereby the rotating member is attached. It is possible to prevent oil from entering the pulse generator by absorbing and holding the oil that cannot be completely removed by the centrifugal force caused by the rotation of the oil by the oil adsorbing sheet and replacing the oil adsorbing sheet.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram showing a position detecting device for an elevator car according to a first embodiment of the present invention.

FIG. 2 is an enlarged perspective view of a main part of a position detecting device for an elevator car according to the first embodiment of the present invention.

FIG. 3 is an enlarged cross-sectional view of a main part taken along a section line XX of the overall configuration diagram of the elevator car position detection device according to the first embodiment of the present invention.

FIG. 4 is a cross-sectional view of the position detecting device for an elevator car according to the second embodiment of the present invention, taken along the line XX in FIG.

FIG. 5 is a sectional view of the position detecting device for an elevator car according to the third embodiment of the present invention, taken along the line XX in FIG.

FIG. 6 is a sectional view of the position detecting device for an elevator car according to the fourth embodiment of the present invention, taken along the line XX in FIG.

FIG. 7 is an enlarged view of a main part showing the configuration of a conventional elevator car position detection device.

[Explanation of symbols]

 3 pulse generating means 3a roller 3b pulse generator 5 upper guider 7 lower guider 5a, 7a sliding piece 12 connecting shaft 20 rotating member 30, 40 oil adsorption sheet

Claims (4)

[Claims] 1. A guide rail fixedly installed upright in a hoistway, an elevator car guided by the guide rail and traveling in the hoistway, and an upper part and a lower part of the elevator car engaged with the guide rail. And a roller disposed between the upper guide element and the lower guide element and rotating in contact with the guide rail, and a roller that is connected to the roller and is proportional to the movement amount of the outer circumference of the roller. A position detecting device for an elevator car, comprising: a pulse generator that generates a pulse. 2. A guide rail fixedly installed upright in the hoistway, an elevator car guided by the guide rail and traveling in the hoistway, disposed in the elevator car, and contacting the guide rail. A rotating roller, a pulse generator that is connected to the roller and generates a pulse proportional to the amount of movement of the outer circumference of the roller, and a rotating member that is arranged between the roller and the pulse generator. A position detecting device for an elevator car. 3. A guide rail that is vertically installed and fixed to a hoistway, an elevator car that is guided by the guide rail and travels in the hoistway, and an elevator car that is disposed in the elevator car and contacts the guide rail. A rotating roller, a pulse generator that is connected to the roller and generates a pulse proportional to the amount of movement of the outer circumference of the roller, and an oil adsorption sheet made of a material that is attached to the side surface of the roller and absorbs and retains oil. A position detecting device for an elevator car, comprising: 4. A guide rail fixedly installed upright in the hoistway, an elevator car guided by the guide rail and traveling in the hoistway, the elevator car being disposed in the elevator car, and contacting the guide rail. A rotating roller; a pulse generator connected to the roller to generate a pulse proportional to the amount of movement of the outer circumference of the roller; a rotating member disposed between the roller and the pulse generator; And an oil adsorbing sheet made of a material that absorbs and holds an oil component, the position detecting device for an elevator car.