JPH09301531A - Movable skid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reliably guide and raise a detecting means to the position in which it is raised from the evacuating position by the large stroke by preventing interference of a guide part with a rolled coil or an external conveying means in an attaching structure for the detecting means in a movable skid. SOLUTION: A first movable member 63 so guided as to be freely raised and lowered by the specified first stroke (a) is provided on a pair of guide parts 61 of a movable frame 5, a second movable members 68 so guided as to be freely raised and lowered by the specified second stroke (b) approximately equal to the first stoke (a) are provided on a pair of guide shafts 66 of the first movable member 63, sensor units 8, 9 are fixedly attached to the tips of the second movable members 68, and the sensor units 8, 9 are reliably guided from the evacuating position to the detecting position in which they are raised by the total stroke (a)+(b) of the first and second strokes so as to be raised and lowered.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a movable skid capable of transferring an object to be conveyed, which is conveyed by an external conveying means such as a crane, to a predetermined position, and more particularly to a movable skid for detecting the object to be conveyed. The present invention relates to an improved mounting structure for detecting means.

[0002]

2. Description of the Related Art Conventionally, various coil transfer devices or movable skids capable of transferring rolling coils carried by a crane are provided at predetermined stations in hot and cold rolling coil carrying equipment. . For example, JP-A-57-
In the coil transfer device disclosed in Japanese Patent No. 1111, a carriage that can move a predetermined distance, a lifting body that has a support portion that can be inserted into a hole of a rolling coil and that is guided up and down by the carriage, and an actuator that drives the lifting body up and down. , Having a sensor or the like for detecting the rolling coil, moving the carriage to the side of the rolled coil that has been conveyed, and inserting the support portion into the hole of the rolling coil,
After the rolling coil is detected by the sensor and the carriage is stopped, the elevating body is lifted so that the rolling coil is supported by the supporting portion and transferred. However, this type of coil transfer device is not configured to transfer the rolling coil to and from the transport carriage.

On the other hand, in a movable skid capable of transferring a rolling coil to and from a carrier vehicle, generally, there is a main body frame, and a mounting portion for supporting the rolling coil supported horizontally on the main body frame. The movable frame, a moving drive mechanism for moving and driving the movable frame in the horizontal direction, a detection means for detecting the rolling coil, and the like are provided.
The horizontal position of the rolling coil conveyed to the upper part of the placing part is detected by an external conveying means such as a crane, and based on the position, the movable drive mechanism horizontally moves the movable frame, and then the rolling coil is moved. When it is lowered, it can be placed at a predetermined position of the placing section, and then the rolling coil can be transferred from the movable skid to the transfer vehicle by a predetermined operation of the transfer device provided in the transfer vehicle.

Conventionally, in the mounting structure of the detecting means in the movable skid, the detecting means is fixedly provided at the tip of the movable member guided by the guide portion of the movable frame so as to be movable up and down by a predetermined stroke. It is mounted so as to be able to move up and down through a retracted position lowered to a lower limit position via a movable member and a detection position raised by the predetermined stroke. When detecting the rolling coil, raise the detecting means to the detecting position, and then, when placing the rolling coil on the mounting part, in the retracted position to prevent interference with the rolling coil or external conveying means. However, in order to reliably detect the rolling coil by the detection means, it is necessary to set the detection position at a position where the detection means is moved up a large stroke from the retracted position.

[0005]

However, in the conventional mounting structure of the detecting means in the movable skid, the detecting means is surely guided and moved up and down between the retracted position and the detected position raised by a large stroke from the retracted position. In order to do so, it is necessary to provide a guide portion that guides the movable member so as to largely project upward from the movable frame, but there is a problem that the rolling coil or an external conveying means interferes with the guide portion, while the guide portion If the guide portion is provided while preventing interference with the rolling coil or the external conveying means, the detecting means cannot be surely guided and moved up and down from the retracted position to the detected position set to the high position.

It is an object of the present invention to prevent interference between a guide part for guiding a movable member and a rolling coil or an external conveying means, and a detecting position which is a retracted position and a detection position which is raised by a large stroke from the retracted position. That is, it is necessary to reliably guide and raise and lower, and to reduce the mounting structure of the detection means with respect to the lifting stroke of the detection means.

[0007]

A movable skid according to claim 1, wherein the movable frame has a main body frame, a movable frame which is horizontally movably supported by the main body frame and has a mounting portion for mounting an object to be conveyed, and the movable frame. In a movable skid having a movement drive mechanism for horizontally moving and driving, a first movable member guided by a guide portion of a movable frame so as to be able to move up and down by a predetermined first stroke, and a first stroke in a guide portion of the first movable member. A second movable member which is guided to move up and down by a predetermined second stroke, which is substantially equal to the second movable member, a detection unit which is fixedly provided at the tip of the second movable member, and which detects an object to be conveyed, and a detection unit. The retracted position lowered to the lower limit position via the first and second movable members, and the first and second retracted positions from the retracted position.
It is provided with an elevating and lowering driving means for elevating and lowering the detection position which is raised by the total stroke of the strokes.

When an object to be conveyed, which is conveyed by an external conveying means such as a crane, is transferred to the movable skid, first, the elevating and lowering drive means elevates the detecting means from the retracted position to the detecting position. The movable member is guided by the guide portion of the movable frame to move upward by a predetermined first stroke,
The movable member is guided by the guide portion of the first movable member and moves upward by a predetermined second stroke, and the detection means attached to the tip end portion of the second movable member passes through the first and second movable members.
The retracted position is switched to the detection position which is raised by the total stroke of the first and second strokes. Next, the horizontal position of the object to be conveyed is detected by the detection means, and based on the position, the movable drive mechanism moves the movable frame in the horizontal direction, and then the elevating drive means moves the detection means from the detection position to the retracted position. When the transport target is lowered by the transport means, the transport target is placed at a predetermined position of the mounting portion of the movable frame.

That is, in this movable skid, the first movable member guided by the guide portion of the movable frame so as to be movable up and down by a predetermined first stroke, and the predetermined stroke substantially equal to the first stroke by the guide portion of the first movable member. Since the second movable member guided so as to move up and down the second stroke is provided and the detecting means is fixedly provided at the tip end portion of the second movable member, the guide portion for guiding the first movable member is moved upward from the movable frame. Since it does not have to be provided so as to be largely protruded, it is possible to prevent interference between the guide portion of the movable frame and the object to be conveyed or the external conveying means, and the detecting means is moved to the retracted position via the first and second movable members. It is possible to reliably guide and ascend and descend from the retracted position to the detection position where a large stroke has been raised. It can be reduced in size.

A movable skid according to a second aspect is provided at a predetermined station in a hot / cold rolling coil transfer facility, and includes a main body frame and a rolling coil that is supported by the main body frame so as to be horizontally movable and is an object to be transferred. In a movable skid having a movable frame having a mounting portion for mounting and a moving drive mechanism for moving and driving the movable frame in a horizontal direction, a first skid which is guided up and down by a predetermined first stroke by a guide portion of the movable frame. A first movable member, a second movable member guided by a guide portion of the first movable member so as to be movable up and down by a predetermined second stroke substantially equal to the first stroke, and a second movable member
From a retracted position fixed to the tip of the movable member for detecting the rolling coil and a retracted position in which the detector is lowered to the lower limit position via the first and second movable members, Elevating and lowering drive means is provided for raising and lowering the detection position raised by the total stroke of the first and second strokes.

That is, in this movable skid, the movable skid provided at a predetermined station in the hot / cold rolling coil transport facility is guided by the guide portion of the movable frame so as to be movable up and down by the predetermined first stroke. A first movable member and a second movable member, which is guided in a guide portion of the first movable member so as to be movable up and down by a predetermined second stroke, which is substantially equal to the first stroke, are provided, and the detection means is fixed to the tip of the second movable member. Since the guide portion for guiding the first movable member does not have to be provided so as to largely project upward from the movable frame, interference between the guide portion of the movable frame and the rolling coil or the external transfer means is prevented. It is possible and, through the first and second movable members, reliably guides the detection means between the retracted position and the detection position which is raised by a large stroke from the retracted position. It can be raised and lowered Te, further, very can be downsized mounting structure of the detection means with respect to the ascending and descending stroke of the detecting means.

According to a third aspect of the invention, in the movable skid according to the first or second aspect of the invention, the detecting means has an ultrasonic sensor capable of detecting the position of the object to be conveyed. That is, the position of the object to be conveyed can be reliably detected by the ultrasonic sensor. Other claim 1 or claim 2
It has the same function as.

A movable skid according to a fourth aspect of the present invention is the movable skid according to the third aspect of the invention, wherein the raising / lowering drive means has an actuator for directly raising / lowering the second movable member. That is, it is possible to raise and lower the first movable member by directly raising and lowering the second movable member, and it is not necessary to provide an actuator for directly raising and lowering the first movable member, which is advantageous in manufacturing cost. The other operation is the same as that of the third aspect.

A movable skid according to a fifth aspect of the present invention is the movable skid according to the fourth aspect of the invention, wherein the actuator is an electric cylinder. That is, when detecting the objects to be conveyed of various sizes by the detection means, the detection means can be easily and reliably positioned at an arbitrary position between the retracted position and the detection position. The other operation is the same as that of the fourth aspect.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. The present embodiment is a movable skid provided at a predetermined station in a hot / cold rolling coil transfer facility and configured to transfer the rolling coil to / from a transfer vehicle. This is an example.

As shown in FIGS. 1 to 4, the movable skid 1
Is provided at a predetermined station in the hot / cold rolling coil C transport facility, and is supported by the pair of left and right body frames 3, 4 and the pair of body frames 3 and 4 so as to be movable in the left and right directions. A pair of movable frames 5, 6, a pair of left and right sensor units 8, 9 provided to detect the rolling coil C, a moving drive mechanism 7 for horizontally driving the pair of movable frames 5, 6; A pair of guide mechanisms 10 and 11 for guiding the pair of sensor units 8 and 9 to move up and down,
It is composed of a pair of elevating and lowering drive mechanisms 12 and 13 for elevating and lowering a pair of sensor units 8 and 9, and a pair of rails 14 on which a carriage 15 travels between a pair of left and right body frames 3 and 4. Are laid in the front-back direction.

Since the pair of main body frames 3 and 4 and the pair of movable frames 5 and 6 have a symmetrical structure, the same reference numerals are given to the same parts, and the right side main body frame 4 and the movable frame 6 are shown. The description of the main body frame 3 and the movable frame 5 on the left side will be omitted. The main body frame 4 has a structure in which a pair of front and rear H-shaped steels 20 extending in the left-right direction are supported by a plurality of steel materials including four columns 21, and the movable frame 6 has a pair of four guide wheels 27. The H-shaped steel 20 is rotatably supported on the inner surface of the H-shaped steel 20 so as to be movable in the left-right direction. In addition, on the inner surface portions of the pair of H-shaped steels 20 facing each other,
Guide member 22 having a smooth surface on which the guide wheel 27 rolls
Is stuck.

The movable frame 6 has a frame main body 25 in which a plurality of steel materials are connected in a substantially frame shape, and a support frame 26 connected to the left end portion of the frame main body 25. A wheel 27 is attached. The upper end of the support frame 26 is formed with a pair of front and rear inclined surfaces 26a inclined toward the center in the front-rear direction, and a pair of pad members 28 are fixed to the pair of inclined surfaces 26a, respectively.
The upper surfaces of these pad members 28 do not have a mounting portion 28c on which the rolling coil C is mounted.

The movement drive mechanism 7 includes a hydraulic cylinder 30 provided on the right side of the main body frame 4, a shaft member 31 disposed below the movable frame 6 in the front-rear direction and rotated by the hydraulic cylinder 30, and a shaft member. 31 and movable frame 6
And a link mechanism 32 for moving the movable frame 6 in the left-right direction through the rotation of the shaft member 31 and the movable frame 5.
A shaft member 33 disposed in the front-rear direction on the lower side of the
The right side shaft member 31 provided on the rear side of the body frames 3 and 4
Transmission mechanism 3 for transmitting the rotation of the shaft to the shaft member 33 on the left side
4. The shaft member 33 and the movable frame 5 are connected to each other to connect the shaft member 33.
It is composed of a link mechanism 35 for moving the movable frame 5 in the left-right direction through the rotation of the.

The right shaft member 31 is rotatably supported by a pair of bearing members 36 and 37 fixed to the body frame 4, and an output rod 38 extending from the hydraulic cylinder 30 is fixed to the shaft member 31. It is pin-connected to the moving member 39. The link mechanism 32 has a structure similar to that of the left-side link mechanism 35. The swing mechanism 40 is fixed to the shaft member 31, one end of which is pin-coupled to the tip of the swing member 40 and the other end of which is the movable frame 6. The link plate 41 is pin-connected to the lower surface of the plate via a bracket 42.

The left shaft member 33 is rotatably supported by a pair of bearing members 43 and 44 fixed to the main body frame 3, and the rotation transmission mechanism 34 has a rear end portion of the pair of shaft members 31 and 33. A pair of connecting members 45, 46 fixed to the
And a connecting shaft member 47 that rotatably connects the pair of connecting members 45 and 46. In the movement drive mechanism 7, when the hydraulic cylinder 30 is driven, the shaft member 31 rotates to move the movable frame 6 in the left-right direction via the link mechanism 32, while the rotation transmission mechanism 34 causes the left shaft member 33 to move. Also rotates to move the movable frame 5 in the left-right direction via the link mechanism 35 to drive the pair of movable frames 5, 6
Are synchronously driven in the left-right direction.

Each of the pair of left and right sensor units 8 and 9 has an ultrasonic sensor 50 for detecting the horizontal position of the rolling coil C, and the ultrasonic sensor 50 causes the rolling coil C to move.
A position detection sensor 51 for detecting a position at which the ultrasonic sensor 50 and the position sensor 51
Is mounted on the upper surface of the sensor mounting bracket 53,
The ultrasonic sensor 5 is provided by the pair of left and right position detection sensors 51 (light emitting device and light receiving device) of the pair of sensor units 8 and 9.
The position where the rolling coil C can be detected is detected by 0, and the horizontal position of the rolling coil C is detected by measuring the distance between them and the pair of left and right ultrasonic sensors 50. It

Since the pair of guide mechanisms 10 and 11 and the pair of lift drive mechanisms 12 and 13 have the same structure, the left guide mechanism 10 and the lift drive mechanism 12 will be described with the same reference numerals. As shown in FIGS. 5 to 8, in the guide mechanism 10, the first movable member 63 guided by the guide portion 61 of the movable frame 5 so as to be able to move up and down by a predetermined first stroke a, and the first movable member 63. A pair of guide shafts 66 (corresponding to guide portions) has a second movable member 68 that is vertically movable and has a predetermined second stroke b substantially equal to the first stroke a. The electric cylinder 70 is mounted on the movable frame 5 via the sensor mounting bracket 53, and the distal end of the piston rod 72 is connected to the sensor mounting bracket 53 so that the second movable member 68 is directly moved up and down via the sensor mounting bracket 53. Is configured.

The guide portion 61 of the movable frame 5 is made of steel material 5.
The plate-shaped member 60 fixed to the left end portion of a has a stopper 62 fixed to the upper end of the guide portion 61, and a pair of block members 64 fixed to the guide portion 61 to the first movable member 63. Slidably engaged with the first movable member 63
Is guided by the guide portion 61 so as to be vertically movable. Further, a second movable member 68 is externally fitted to a guide shaft 66 provided on the left end side of the first movable member 63 via a bracket 65, and is guided so as to be vertically movable in the second stroke b.

The transport carriage 15 will now be described. As shown in FIG. 2, the transport carriage 15 includes wheels 16 rolling on the rails 14, drive motors 17 for rotationally driving the wheels 16, and movable skids 1. By having the transfer device 18 and the like for transferring the rolling coil C set to, and raising the mounting member 19 between the movable frames 5 and 6 by a predetermined operation of the transfer device 18, The rolling coil C set at a predetermined position of the mounting portion 28a is transferred to the transport carriage 15.

The operation of the movable skid 1 will be described.
When the rolling coil C that is supported and conveyed by the coil tongs A (see FIG. 2) of the crane is transferred to the movable skid 1, first, the pair of sensor units 8 and 9 is raised from the retracted position to the detection position. At this time, when the piston rod 72 is driven to move forward by the electric cylinder 70, the second movable member 68 is moved from the state shown in FIG. 6 to the first movable member 63 as shown in FIG. Is guided by the guide shaft 66 to move up by the first stroke a, and the upper guide body 68 of the second movable member 68 comes into contact with the upper bracket 63 of the first movable member 63. continue,
As shown in FIG. 8, the first guide member 63 is guided by the guide portions 61 of the movable frames 5 and 6, and the first and second movable members 63 and 68 are integrally lifted by the second stroke b,
The sensor units 8 and 9 are elevated from the retracted position by the total stroke a + b of the first and second strokes a and b, and are switched to the detection position.

After that, the pair of sensor units 8 and 9 detect the horizontal position of the rolling coil C that has been conveyed to a position above the placing portion 28a by the crane, and drive the movement based on the position of the rolling coil C. After the pair of movable frames 5 and 6 are moved and driven by the mechanism 7 in the left-right direction, the elevating and lowering drive means 12 and 13 lower the sensor units 8 and 9 at the detection position to the retracted position, and then the rolling coil C is moved to the crane. When it is lowered by
The rolling coil C is placed at a predetermined position of a, and then the rolling coil C of the movable skid 1 is transferred to the transport carriage 15 by a predetermined operation of the transfer device 18 of the transport carriage 15.

That is, according to the movable skid 1, the predetermined first stroke a is applied to the guide portion 61 of the movable frames 5 and 6.
Since the first movable member 63 guided up and down and the guide shaft 66 of the first movable member 63 are provided with the predetermined second stroke b substantially equal to the first stroke a and the second movable member 68 guided up and down. Since the guide portions 61 of the movable frames 5 and 6 for guiding the first movable member 63 do not have to be provided so as to largely project upward from the movable frames 5 and 6, the guide portion 61 and the transfer coil C or the coil tongs of the crane are provided. The interference with A can be prevented.

Moreover, the sensor units 8 and 9 are surely guided and moved up and down through the first and second movable members 63 and 68 between the retracted position and the detection position which is raised by a large stroke from the retracted position. Furthermore, the mounting structure of the sensor units 8 and 9 can be made extremely small with respect to the lifting stroke of the sensor units 8 and 9. Further, since the ultrasonic sensor 50 capable of detecting the position of the rolling coil C is provided in the sensor units 8 and 9, the position of the rolling coil C can be reliably detected.

Further, in the lifting drive mechanisms 12 and 13,
Electric cylinder 70 for directly raising and lowering the second movable member 68
Since the second movable member 68 is directly moved up and down, the first movable member 63 can be moved up and down.
Since it is not necessary to provide an actuator for directly moving the movable member 63 up and down, manufacturing cost is advantageous. Further, by providing an electric cinder on the lifting drive mechanisms 12 and 13, the sensor units 8 and 9 are placed between the retracted position and the detected position, for example, when the sensor units 8 and 9 detect rolling coils of various sizes. It can be easily and reliably positioned at any position.

The above embodiment is merely an example, and those skilled in the art can apply the present invention to movable skids having various structures without departing from the scope of the present invention, and various mechanisms and devices described above can be used. Of course, changes can be added and implemented.

[0032]

According to the movable skid of the first aspect, the first movable member guided by the guide portion of the movable frame so as to be movable up and down by the predetermined first stroke, and the guide portion of the first movable member has substantially the first stroke. A second movable member that is guided to move up and down by an equal predetermined second stroke, a detection unit fixedly provided at the tip of the second movable member for detecting an object to be conveyed, and first and second moving units. Since the elevating and lowering drive means is provided for elevating and lowering over the retracted position that is lowered to the lower limit position through the member and the detected position that is elevated by the total stroke of the first and second strokes from the retracted position, the first movable unit is provided. Since the guide part for guiding the member does not have to be provided so as to largely project upward from the movable frame, it is possible to prevent interference between the guide part of the movable frame and the object to be conveyed or the external conveying means, and Through a second movable member, it can be reliably guided to lift over the detecting means from the retracted position and the retracted position to the detection position obtained by the large stroke increases,
Furthermore, the mounting structure of the detection means can be made extremely small with respect to the lifting stroke of the detection means.

According to the movable skid of claim 2, the hot skid
In a movable skid provided at a predetermined station in a cold rolling coil transfer facility, a first movable member guided by a guide portion of a movable frame so as to be able to move up and down by a predetermined first stroke, and a first movable member at a guide portion of the first movable member. A second movable member, which is guided to move up and down by a predetermined second stroke, which is approximately equal to one stroke, a detection unit fixedly provided at the tip of the second movable member for detecting the rolling coil, and a first detection unit. Since the elevating and lowering drive means is provided to elevate and lower over the retracted position lowered to the lower limit position via the second movable member and the detected position raised by the total stroke of the first and second strokes from the retracted position. Since the guide part for guiding the first movable member does not have to be provided so as to largely project upward from the movable frame, the guide part of the movable frame and the rolling coil or outside Interference with the conveying means can be prevented, and the detecting means is surely guided and moved up and down through the first and second movable members between the retracted position and the detected position raised by a large stroke from the retracted position. Further, the mounting structure of the detecting means can be made extremely small with respect to the lifting stroke of the detecting means.

According to the movable skid of claim 3, the same effect as that of claim 1 or 2 can be obtained, but the detecting means is
Since the ultrasonic sensor that can detect the position of the object to be conveyed is included, it is possible to reliably detect the position of the object to be conveyed.

According to the movable skid of claim 4, the same effect as in claim 3 can be obtained, but since the elevating and lowering drive means has an actuator for directly elevating and lowering the second movable member,
By directly raising and lowering the second movable member, the first movable member can be raised and lowered, and it is not necessary to provide an actuator for directly raising and lowering the first movable member, which is advantageous in manufacturing cost.

According to the movable skid of claim 5, the same effect as that of claim 4 can be obtained, but since the actuator is an electric cylinder, it is possible to detect the object to be conveyed of various sizes by the detecting means. The means can be easily and surely positioned at any position between the retracted position and the detection position.

[Brief description of drawings]

FIG. 1 is a plan view of a movable skid according to an embodiment of the present invention.

FIG. 2 is a front view of the movable skid.

3 is a sectional view taken along line III-III in FIG.

4 is a sectional view taken along line IV-IV in FIG.

FIG. 5 is an enlarged plan view of a main part of the movable skid.

6 is a sectional view taken along line VI-VI of FIG.

FIG. 7 is an enlarged sectional view of a main part of the movable skid (when the sensor unit first stroke a is raised).

FIG. 8 is an enlarged cross-sectional view of a main part of the movable skid (when the sensor unit first and second total strokes a + b rise).

[Explanation of symbols]

 C Rolling coil 1 Movable skid 3,4 Main body frame 5,6 Movable frame 7 Movement drive mechanism 8,9 Sensor unit 10,11 Guide mechanism 12,13 Lifting drive mechanism 28c Mounting part 50 Ultrasonic sensor 51 Position detection sensor 61 guide Part 63 First movable member 66 Guide shaft 68 Second movable member 70 Electric cylinder

Claims (5)

[Claims] 1. A main body frame, a movable frame having a mounting portion for supporting an object to be conveyed which is supported by the main body frame so as to be horizontally movable, and a movement drive mechanism for moving and driving the movable frame in the horizontal direction. In the movable skid, a first movable member guided by a guide portion of the movable frame so as to be able to move up and down by a predetermined first stroke, and a predetermined second stroke that is substantially equal to the first stroke by a guide portion of the first movable member. Second guided by
A movable member, a detection unit fixedly provided at the tip of the second movable member for detecting an object to be conveyed, and the detection unit lowered to the lower limit position via the first and second movable members. The retracted position and the first and second from the retracted position
A movable skid comprising: an elevating and lowering drive means for vertically ascending and descending over a detection position raised by a total stroke. 2. A hot / cold rolling coil transfer facility, which is provided at a predetermined station, is provided with a main body frame and a rolling coil which is supported by the main body frame and is horizontally movable so as to be an object to be transferred. A movable frame having a mounting portion, and a movable skid having a movement drive mechanism for moving and driving the movable frame in a horizontal direction, wherein a first movable member guided by a guide portion of the movable frame so as to be vertically movable up and down by a predetermined first stroke, A second guide which is vertically movable by a predetermined second stroke substantially equal to the first stroke in the guide portion of the first movable member.
A movable member, a detection unit fixedly provided at the tip of the second movable member for detecting the rolling coil, and the detection unit lowered to the lower limit position via the first and second movable members. The retracted position and the first and second from the retracted position
A movable skid comprising: an elevating and lowering drive means for vertically ascending and descending over a detection position raised by a total stroke. 3. The movable skid according to claim 1, wherein the detection unit has an ultrasonic sensor capable of detecting the position of the object to be conveyed. 4. The movable skid according to claim 3, wherein the lifting drive means has an actuator that directly drives the second movable member up and down. 5. The movable skid according to claim 4, wherein the actuator is an electric cylinder.