WO2008075897A1

WO2008075897A1 - Rail type transportation apparatus

Info

Publication number: WO2008075897A1
Application number: PCT/KR2007/006658
Authority: WO
Inventors: Seong-Jong Han; Jong-Ung Choi; Young-Jun Park; Dong Bae Lee
Original assignee: Samsung Heavy Ind. Co., Ltd.
Priority date: 2006-12-19
Filing date: 2007-12-18
Publication date: 2008-06-26
Also published as: CN101563270A; JP2010513136A; KR20080056916A; JP5027248B2; CN101563270B; KR101302208B1

Abstract

A rail type transportation apparatus is used in transporting various kinds of automated equipments for performing different tasks with respect to heat insulators attached to the inner wall surfaces of a ship cargo compartment. The apparatus includes a pair of rails removably secured to the heat insulators and a carriage assembly mountable to and movable along the rails. The carriage assembly includes a carriage frame, a driving unit mounted to the carriage frame and provided with travel wheels, a pressing unit mounted to the carriage frame, a support wheel unit movable toward and away from the rails for engagement and disengagement with the rails and a travel brake device for stopping movement of the carriage assembly. The apparatus further includes a controller for controlling operations of the carriage assembly.

Description

RAIL TYPE TRANSPORTATION APPARATUS

Technical Field

[1] The present invention is directed to a rail type transportation apparatus that transports various kinds of automated equipments for performing different tasks with respect to heat insulators attached to the inner wall surfaces of a ship cargo compartment. Background Art

[2] In general, several thousands or several ten thousands of panel type heat insulators

(e.g., insulation panels) are attached to the inner wall surfaces of a ship cargo compartment in an effort to thermally insulate the internal space of the cargo compartment. It is the current situation that the task of attaching the heat insulators is performed manually for the most parts and partly performed by means of an automated machine. Particularly, the conventional automated machine for performing tasks within a ship cargo compartment is designed and manufactured for use with a specified panel, thus posing a number of problems noted below.

[3] The term specified panel refers to a kind of panel formed into a generally rectangular parallelepiped shape and exclusively used in a specified cargo compartment. The panel includes a heat insulating layer and a plywood layer overlaid on the heat insulating layer. A slit is formed outside the juncture between the plywood layer and the heat insulating layer. A plurality of the specified panels is arranged on the inner wall surfaces of the cargo compartment in conformity with the technical standards regarding the cargo compartment. Inter-insulator channels are formed between the neighboring panels to extend in lattice-like directions. In view of this, the conventional automated machine for performing tasks within the ship cargo compartment makes use of a driving method in which the machine is moved along the inter-insulator channels by using a frictional force generated when pressing the side surface of the plywood layer as a support base. In particular, the conventional automated machine includes a driving unit which moves in a state that a guide mechanism such as a ski or the like is inserted into and supported by the slit.

[4] Since the driving unit of the conventional automated machine needs to be moved while pressing the plywood layer of the panel, however, there is a fear that the side surface region of the plywood layer is broken by the excessive force applied thereto.

[5] Furthermore, a slit of specified shape must be left underneath the plywood layer of the panel and a guide mechanism inserted into the slit has to be mounted to the conventional automated machine, which entails a technical difficulty. In this regard, the guide mechanism inserted into the slit serves as a kind of safety device that prevents the driving unit from being dropped or removed from the inter- insulator channels during upward, downward, left and right movement of the driving unit.

[6] Particularly, due to the arrangement characteristics of the panel, regions where the plywood layer does not exist are created here and there in the inter-insulator channels. Thus, it is necessary to additionally employ a plurality of connectors for bridging the regions where the plywood layer is absent. Setting aside the inconvenience encountered in installing the connectors, it is difficult for the conventional automated machine to secure accurate moving performance in case the connectors are additionally installed in the plywood layer lacking regions.

[7] In addition, insulation panels are manually attached in the prior art. Therefore, gaps are left in the junctures between the plywood layers of the respective panels, even if a worker having a plenty of experience makes every effort to accurately arrange and attach the panels to the inner wall surfaces of the cargo compartment. The presence of gaps makes it difficult for the wheels of a machine to roll along an accurate way. Disclosure of Invention Technical Problem

[8] In view of the above-noted problems, it is an object of the present invention to provide a rail type transportation apparatus that transports various kinds of automated equipments for performing different tasks with respect to heat insulators attached to the inner wall surfaces of a ship cargo compartment, which apparatus is easy to install and capable of increasing the efficiency of tasks performed with respect to the heat insulators and exhibiting accurate travel performance while protecting the heat insulators from damage. Technical Solution

[9] With the above objects in view, the present invention provides a rail type transportation apparatus for transporting various kinds of automated equipments for performing different tasks with respect to heat insulators attached to the inner wall surfaces of a ship cargo compartment, including: a pair of rails removably secured to the heat insulators; a carriage assembly mountable to and movable along the rails; and a controller for controlling operations of the carriage assembly.

[10] As used herein, the terms "different postures" assumed by the transportation apparatus while automatically moving on the inner wall surfaces of a ship cargo compartment are used to mean a flat posture, a horizontal posture, a vertical posture and an overhead posture.

Advantageous Effects

[11] The rail type transportation apparatus of the present invention is of the type in which a carriage assembly travels along rails. This provides an advantage in that there is no fear of breakage of heat insulators or plywood layers.

[12] Furthermore, the rail type transportation apparatus of the present invention is adapted to press travel wheels and support wheels into contact with the rails at an initial setting time by use of a pressing motor and a ball screw mechanism of a pressing unit. This provides an advantage in that a pressing operation can be automated.

[13] Furthermore, the rail type transportation apparatus of the present invention employs a structure in which a feeding force of the ball screw mechanism of the pressing unit can be regulated by a resilient reaction force of a pressure-regulating spring. Therefore, it is possible to press the travel wheels and the support wheels into close contact with the rails despite variations of the rail status in a job site. This provides an advantage in that an accurate moving operation of the carriage assembly is mechanically assured in any of different postures.

[14] Furthermore, the rail type transportation apparatus of the present invention controls the pressing force in an optimized manner by use of a displacement measuring instrument. This provides an advantage in that the transportation apparatus can be operated safely.

[15] Moreover, the rail type transportation apparatus of the present invention is provided with an automated pressing unit. This provides an advantage in that the carriage assembly can be mounted and demounted in a rapid and ease manner, thereby maximizing the convenience of a worker.

[16] In addition, the rail type transportation apparatus of the present invention provides an advantage in that it is capable of shortening the cargo compartment building time to thereby improve productivity and also capable of automating the cargo compartment building process to thereby enhance building accuracy. Brief Description of the Drawings

[17] Fig. 1 is a perspective view showing a rail type transportation apparatus in accordance with one embodiment of the present invention.

[18] Fig. 2 is an exploded perspective view of the rail type transportation apparatus shown in Fig. 1.

[19] Fig. 3 is a side elevational section view of the rail type transportation apparatus shown in Fig. 1.

[20] Fig. 4 is an enlarged section view of the portion indicated by a circle A in Fig. 3.

Best Mode for Carrying Out the Invention

[21] A preferred embodiment of the present invention will now be described in detail with reference to the accompanying drawings.

[22] Fig. 1 is a perspective view showing a rail type transportation apparatus in accordance with one embodiment of the present invention. Fig. 2 is an exploded per- spective view of the rail type transportation apparatus shown in Fig. 1. Fig. 3 is a side elevational section view of the rail type transportation apparatus shown in Fig. 1. Fig. 4 is an enlarged section view of the portion indicated by a circle A in Fig. 3.

[23] As shown in Fig. 1, the rail type transportation apparatus of the present invention includes a carriage assembly 10 that transports various kinds of automated equipments for performing different tasks with respect to heat insulators 1, e.g., insulation panels, attached to the inner wall surfaces of a ship cargo compartment. In this regard, inter- insulator channels 9 are formed just above the gaps 8 between the heat insulators 1 in such a manner as to extend in lattice-like directions according to the arrangement of the heat insulators 1.

[24] The rail type transportation apparatus of the present invention further includes a pair of parallel rails 200 fixedly secured to the heat insulators 1 existing in the opposite lateral edges of the inter-insulator channels 9. The rails 200 serve as a support base along which the carriage assembly 10 travels.

[25] The carriage assembly 10 is designed to travel along the inter-insulator channels 9 with no likelihood of causing damage to the heat insulators 1 around the inter- insulator channels 9.

[26] The carriage assembly 10 includes a skeleton-like carriage frame 110 for supporting automated equipments or devices required in performing tasks within the cargo compartment.

[27] The carriage assembly 10 includes a pair of driving units 300 arranged on the opposite side portions of the carriage frame 100. The driving units 300 are operated by motive power, e.g., electric power, under the control of a controller 800 and adapted to drive the carriage assembly 10 while making frictional contact with the rails 200.

[28] The carriage assembly 10 further includes a pressing unit 400 mounted to the carriage frame 100 and operated by motive power, e.g., electric power, under the control of the controller 800. The pressing unit 400 performs a pressing operation by which the respective driving units 300 are pressed toward the rails 200 and a retracting operation by which the respective driving units 300 are moved away from the rails 200.

[29] The carriage assembly 10 further includes a pair of support wheel units 500 attached to the driving units 300 so that they can be moved toward and away from the rails 200 for engagement and disengagement with the rails 200. Once the support wheel units 500 are engaged with the rails 200, the carriage assembly 10 is prevented from any inadvertent separation from the rails 200.

[30] The carriage assembly 10 further includes a pair of auxiliary wheels 600 attached to the lower surface of the carriage frame 100 so that they can make rolling contact with the rails 200. [31] The carriage assembly 10 further includes a travel encoder 700 fixed to the carriage frame 100 and electrically connected to the controller 800. The travel encoder 700 detects the revolution number of one of the auxiliary wheels 600 and feeds signals indicative of the detected revolution number to the controller 800 so that the controller 800 can accurately feed-back control the moving speed of the rail type transportation apparatus.

[32] Hereinafter, the afore-mentioned components will be described in more detail with reference to Fig. 2. With regard to the components symmetrically arranged in the carriage frame 100 as viewed in Fig. 3, only the components lying on one side (e.g., on the right side) will be described for avoidance of duplicate description.

[33] Referring to Fig. 2, the carriage frame 100 is a structural body for holding a controller of various devices or systems, a travel controller, an automation module, a portable power source, a safety device, other devices required in performing assigned tasks. The carriage frame 100 is made of an extremely lightweight structural material (e.g., aluminum) and is fabricated into a structure having an increased resistance to distortion or other deformation.

[34] The carriage frame 100 can be fabricated into a distortion-proof structure by fixing a plurality of crossbeams, including a front crossbeam, to left and right girder members in a spaced-apart relationship. In addition to the pressing unit 400, various kinds of equipments, devices, sensors and components can be freely attached to the carriage frame 100 by using fixture holes of the carriage frame, bolts and nuts. Furthermore, the carriage frame 100 has a plurality of legs 110 and 111 formed on the upper and side surfaces thereof for use in storing the carriage frame 100 and a plurality of handles 112 used in manually transporting the carriage frame 100.

[35] The rails 200 are fixed to the top corner portions of the heat insulators 1 positioned on the opposite sides of the inter-insulator channels 9. The rails 200 may extend in the longitudinal direction of the inter-insulator channels 9 (e.g., in an X-axis direction). Each of the rails 200 is provided with a bottom step portion 211 that makes close contact with the top corner portion of the corresponding heat insulator 1.

[36] Each of the rails 200 has an engaging surface 212 recessed from the upper surface of the corresponding rail 200 on the opposite side from the bottom step portion 211. Guide surfaces 213 and 214 inclined upwardly and downwardly are formed in the upper and lower regions of a five- angled one lateral end portion of each of the rails 200. A friction-contact surface 216 is formed in the middle region of the five-angled one lateral end portion between the guide surfaces 213 and 214.

[37] As best shown in Fig. 1, each of the rails 200 has a plurality of fixture holes 77 and each of the heat insulators 1 has a plurality of bolt holes 7 aligned with the fixture holes 77. Therefore, each of the rails 200 can be temporarily and removably fixed to the corresponding heat insulator 1 by fitting fasteners 70 such as bolts or clamps through the fixture holes 77 and the bolt holes 7. In other words, each of the rails 200 is pressed against the top corner portion of the corresponding heat insulator 1 at the bottom step portion 211 thereof and then temporarily fixed to the corresponding heat insulator 1 by means of the fasteners 70. The rails 200 are detached from the heat insulators 1 once a desired task is completed. As an alternative, the friction-contact surface 216 may be replaced by a rack gear and the travel wheel 325 may be replaced by a pinion gear.

[38] It is preferred that the rails 200 are made of a wood material such as a timber or the like, a high strength lightweight metal such as aluminum alloy or the like, a high strength synthetic resin material such as engineering plastic or the like, or a composite material such as glass reinforced plastic, carbon fiber reinforced plastic or the like.

[39] The rails 200 may be made of any material as long as it can bear a preset load or can exhibit a permissible strain great enough to bear the load. Furthermore, a rack gear groove 215 for engaging with a pinion gear (not shown) of another driving mechanism is additionally formed in one corner of the engaging surface 212 of each of the rails 200 to assure stable and accurate travel of the carriage assembly 10.

[40] Support wheels 510 and 511 of the support wheel units 500 make pressure contact with the guide surfaces 213 and 214 of the rails 200. Thus, the guide surfaces 213 and 214 support the carriage assembly 10 so that the carriage assembly 10 can assume one of different postures. Travel wheels 325 of the driving units 300 make pressure contact with the friction-contact surfaces 216 of the rails 200 so that the carriage assembly 10 can be driven in the afore-mentioned posture. In this regard, the pressure contact occurs when the pressing unit 400 presses the support wheel units 500 and the driving units 300 against the rails 200.

[41] Each of the driving units 300 is mounted to a wheel carriage 401 of the pressing unit

400 disposed in a space below the carriage frame 100. Examples of the wheel carriage

401 include a knuckle and a strake, both of which are formed into a bar shape or plate shape.

[42] The travel motor 320, the travel wheel 325 and one of the support wheel units 500 are mounted to the wheel carriage 401. The pressing power is transmitted from a pressing motor 410 to the wheel carriage 401 and the support wheel unit 500 through a double-threaded screw shaft 460, a nut block 470 and a pressing member 480. The travel wheel 325 is kept in contact with the corresponding rail 200 by means of a linear motion guide.

[43] If the double-threaded screw shaft 460 is rotated in a reverse direction, a pressure- regulating spring 490 is released from a compressed state. Therefore, the wheel carriage 401 connected to the pressing member 480 through guide shaft members 403 is moved laterally inwardly, whereby the driving unit 300 and the support wheel unit 500 are returned to their original positions and kept out of contact with the corresponding rail 200.

[44] The wheel carriage 401 has a plurality of horizontally extending guide holes 402 formed in the middle portion thereof. The guide shaft members 403 are inserted into the guide holes 402 at one end portions thereof so that the guide shaft members 403 can be moved in a horizontal direction. The travel motor 320 is attached to one longitudinal end portion of the wheel carriage 401 in such a manner as to extend vertically upwardly. The travel motor 320 has a rotating shaft that protrudes downwardly.

[45] Each of the support wheel units 500 is attached to the lower surface of the other longitudinal end portion of the wheel carriage 401. One member 404 (e.g., a guide rail) of a well-known linear motion guide is attached to the upper surface of the other longitudinal end portion of the wheel carriage 401. Attached to the bottom portion of the carriage frame 100 is the other member 405 (e.g., a guide block) of the linear motion guide that remains in a sliding contact relationship with the one member 404. The linear motion guide ensures that the wheel carriage 401, the driving units 300 and the support wheel units 500 can make linear reciprocating movement during the pressing or releasing operation of the pressing unit 400.

[46] Referring collectively to Figs. 2 and 4, the rotating shaft 319 of the travel motor 320 extends in a vertical direction (i.e., a Z-axis direction) through a bearing 318 fitted to the wheel carriage 401. A driven shaft 337 is operatively connected to the lower end of the rotating shaft 319 at a right angle through a bevel gear set 329.

[47] A travel brake device 330 is mounted to the driven shaft 337 of each of the driving units 300. Responsive to a brake control signal supplied from the controller 800, the travel brake device 330 is adapted to rapidly lock up or release each of the driving units 300.

[48] The travel brake device 330 includes a brake housing and a brake bracket 339 fixed to the housing. The brake bracket 339 is connected to the wheel carriage 401 at its top end. The travel brake device 330 includes an electromagnetic restraint means arranged within the housing. The electromagnetic restraint means is electrically connected to the travel controller 800 shown in Fig. 1. The travel brake device 330 is normally in an initial state in which the electromagnetic restraint means is kept out of engagement with the driven shaft 337.

[49] Under an emergency situation or when there is a need to stop the carriage assembly

10 during a normal operation process, the travel controller 800 issues a brake control signal so that the electric power (of an emergency power source such as a battery or a condenser or a commercial power source) can be supplied to the electromagnetic restraint means. In response, the electromagnetic restraint means performs a locking operation by allowing an electromagnet member thereof to fasten the driven shaft 337. As a result, the driven shaft 337, the travel wheel 325 and the travel motor 320 are held against rotation. In this connection, the travel wheel 325 is directly secured to the rotating shaft 319 of the travel motor 320 and is rotated upon operation of the travel motor 320.

[50] The travel motor 320 and the below-mentioned pressing motor 410 may be either DC motors or servo motors and are composed of a reduction gear, a bearing and a motor encoder. The travel motor 320 and the pressing motor 410 are connected to the travel controller 800 to receive electric power.

[51] Referring again to Fig. 2, the pressing unit 400 makes use of a ball screw mechanism, one kind of screw motion mechanisms, operatively connected to the pressing motor 410. More specifically, the pressing unit 400 includes: a pressing motor 410 supplied with electric power from the travel controller 800 for generating a torque; a first mounting bracket 420 having a generally "h"-like cross section, the first mounting bracket 420 fixedly secured to one side (the left girder member) of the carriage frame 100, the first mounting bracket 420 adapted to support the pressing motor 410 at its top portion and provided with a pair of coaxial bearings at its bottom side walls; a second mounting bracket 421 having a generally inverted "U"-like cross section, the second mounting bracket 421 fixedly secured to the other side (the right girder member) of the carriage frame 100 in a spaced- apart facing relationship with the first mounting bracket 420, the second mounting bracket 421 provided with a pair of coaxial bearings at its bottom side walls; a driving pulley 430 fixed to the rotating shaft of the pressing motor 410; a driven pulley 450 operatively connected to the driving pulley 430 through a timing belt 440 for receiving the torque of the pressing motor 410; a double-threaded screw shaft 460 fitted to the driven pulley 450 at one end thereof and rotatably supported at its opposite ends by the bearings of the first mounting bracket 420 and the bearings of the second mounting bracket 421; nut blocks 470 threadedly coupled to one thread portion and the other thread portion of the double-threaded screw shaft 460 for converting rotational movement of the screw shaft 460 to linear reciprocating movement thereof; pressing members 480 attached to the bottom portions of the nut blocks 470; and pressure-regulating springs 490 retained between the pressing members 480 and the wheel carriage 401. In this regard, one thread portion and the other thread portion of the double-threaded screw shaft 460 are formed in the opposite directions from each other.

[52] With the configuration set forth above, the pressing force referred to in the present invention is equal to a total sum of the moving force of the nut blocks 470 and the pressing members 480 generated upon operation of the pressing unit 400 and the resilient reaction force of the pressure-regulating springs 490 compressed by the pressing members 480.

[53] Although not shown in the drawings, a pressing brake device for stopping movement of the pressing motor 410 and other components operatively connected thereto may be additionally installed in the double-threaded screw shaft 460 or the rotating shaft of the pressing motor 410. This pressing brake device may have substantially the same structure as that of the travel brake device 330 described above.

[54] As clearly illustrated in Fig. 4, when the double-threaded screw shaft 460 is rotated in the forward or reverse direction, the nut blocks 470 and the pressing members 480 threadedly coupled to one thread portion and the other thread portion of the screw shaft 460 are simultaneously moved laterally outwardly or inwardly of the carriage frame 100 at the same stroke S.

[55] In this regard, each of the pressing members 480 is formed of a horizontal plate 481 and a vertical plate 482. The guide shaft members 403 are connected to the vertical plate 482 of each of the pressing members 480 at the other ends thereof. The pressure- regulating springs 490 are retained around the guide shaft members 403. The guide shaft members 403 are inserted into the guide holes 402 of the wheel carriage 401 at one ends thereof and restrained by pins 483 to ensure that the guide shaft members 403 are not separated from the guide holes 402 by the resilient reaction force of the pressure-regulating springs 490.

[56] The pressure-regulating springs 490 are brought into contact with the side surface of the vertical plate 482 of each of the pressing members 480 at one ends thereof and are coupled to the side surface of the wheel carriage 401 at the other ends thereof through a displacement measuring instrument 491 (a potentiometer) which in turn is connected to the controller 800 shown in Fig. 1. Alternatively, the displacement measuring instrument 491 may be installed between the vertical plate 482 of each of the pressing members 480 and the pressure-regulating springs 490.

[57] Upon operation of the pressing unit 400, the pressing force, i.e., a total sum of the resilient reaction force of the pressure-regulating springs 490 and the moving force of the nut blocks 470 and the pressing members 480 is transmitted to the wheel carriage 401 through the pressure-regulating springs 490. In response, the travel wheel 325 of each of the driving units 300 and the support wheels 510 and 511 of each of the support wheel units 500 are resiliently pressed into contact with the friction-contact surface 216 and the guide surfaces 213 and 214 of each of the rails 200. Thus, the travel wheel 325 and the support wheels 510 and 511 can make close contact with each of the rails 200 regardless of the situation in a job site. As a result, accurate movement of the carriage assembly 10 is mechanically assured in any one of the different postures.

[58] The controller 800 shown in Fig. 1 is adapted to control the operation of the pressing motor 410 of the pressing unit 400 and is capable of realizing optimized force control by using signals of the displacement measuring instrument 491 at the initial setting time and during the travel process.

[59] The displacement measuring instrument 491, the travel motor 320, the travel brake device 330, the pressing brake device, the pressing motor 410 and the travel encoder 700 are electrically connected to the controller 800 so that they can be supplied with electric power and can transmit signals to the controller 800.

[60] The pressing force of the pressing unit 400 is controlled by means of a force control algorithm stored in a memory of the controller 800 and executed by a central processing unit of the controller 800. Using the displacement measuring instrument 491, the controller 800 executes the force control algorithm in such a way that the driving units 300 and the support wheel units 500 are moved laterally outwardly of the carriage frame 100 or returned back to their original positions in keeping with the job site situation. The moving force of the respective components of the pressing unit 400 is regulated by the resilient reaction force of the pressure-regulating springs 490 to thereby keep the pressing force constant. This allows the carriage assembly 10 to be operated accurately.

[61] Referring again to Fig. 2, each of the support wheel units 500 includes: a mounting base 501 attached to the lower surface of the other longitudinal end portion of the wheel carriage 401; a spring-damper type cylinder portion 502 fixedly secured to the mounting base 501; a rod 503 extendibly fitted to the cylinder portion 502; a wheel guide block 504 attached to the tip end of the rod 503; and a plurality of support wheels 510 and 511 rotatably mounted to the upper and lower oblique surfaces of the wheel guide block 504 so that they can make contact with each of the rails 200.

[62] As can be seen in Fig. 4, the support wheels 510 and 511 are kept inclined at an upward wheel arrangement angle of +45 degrees and at a downward wheel arrangement angle of -45 degrees with respect to an imaginary plane (in which the axis of the rod 503 shown in Fig. 2 lies). Consequently, the support wheels 510 and 511 can make close contact with the guide surfaces 213 and 214 of each of the rails 200.

[63] Referring to Fig. 2, a plurality of auxiliary wheels 600 is rotatably mounted to the lower surface of the carriage frame 100 through a wheel mounting bracket. As best shown in Fig. 3, the auxiliary wheels 600 roll in contact with the rails 200 and support the carriage frame 100 in a movable manner.

[64] Referring again to Fig. 2, the travel encoder 700 is directly coupled to the shaft of the auxiliary wheels 600 through a shaft coupler (not shown). Alternatively, the travel encoder 700 may be attached to the carriage frame 100 through a sensor wheel rotating together with one of the auxiliary wheels 600 so that it can detect the revolution number of the corresponding auxiliary wheel 600. [65] The travel encoder 700 transmits a signal indicative of the detected revolution number of the corresponding auxiliary wheel 600 to the controller 800. The controller 800 calculates a total travel distance of the carriage assembly 10 using the known circumferential length of the auxiliary wheels 600 stored in the memory of the controller 800 and the revolution number of the corresponding auxiliary wheel 600 thus transmitted. The controller 800 can calculate the moving speed of the carriage assembly 10 using the total travel distance thus calculated and the operation time measured by a timer of the controller 800.

[66] Hereinafter, description will be made on the operation of the rail type transportation apparatus in accordance with the present invention.

[67] Referring to Fig. 3, an operator performs an initial setting task. In other words, the rails 200 are secured to the top corner portions of the heat insulators 1 arranged on the opposite sides of the inter-insulator channels 9. At this time, the rails 200 are fixed to the heat insulators 1 by means of the fasteners 70. Then, the operator brings the carriage frame 100 of the carriage assembly 10 into a space above the inter- insulator channels 9 and lays it down on the upper surfaces of the rails 200. In this process, the auxiliary wheels 600 make contact with the upper surfaces of the rails 200 and support the carriage frame 100.

[68] Then, the operator turns the controller 800 on. While performing initialization, the controller 800 checks whether the carriage frame 100 is placed on the rails 200 by using a separately installed contact switch (not shown).

[69] Subsequently, the controller 800 allows the pressing unit 400 to carry out a pressing operation. In the pressing operation, the pressing motor 410 of the pressing unit 400 rotates the driving pulley 430, the timing belt 440, the driven pulley 450 and the double-threaded screw shaft 460 in the forward or reverse direction.

[70] In response, one thread portion and the other thread portion of the screw shaft 460 move the nut blocks 470 away from each other, as a result of which the nut blocks 470 are moved toward the rails 200. More specifically, as can be seen in Fig. 4, the pressing member 480 connected to each of the nut blocks 470 compresses the pressure- regulating springs 490 in the same direction as the corresponding nut block 470 moves. The wheel carriage 401 is pressed toward the corresponding rail 200 by the biasing force of the pressure-regulating springs 490 thus compressed.

[71] Consequently, the travel wheel 325 of each of the driving units 300 attached to the wheel carriage 401 is pressed against the friction-contact surface 216 and, at the same time, the support wheels 510 and 511 of each of the support wheel units 500 fixed to the wheel carriage 401 are pressed into contact with the guide surfaces 213 and 214.

[72] The releasing operation of the pressing unit 400 is performed in the reverse order of the pressing operation. [73] Next, description will be made on the travel control operation of the travel controller

800.

[74] The travel controller 800 measures the magnitude of the pressing force, based on the signals inputted from the displacement measuring instrument 491, and controls the torque of the pressing motor 410 of the pressing unit 400 according to the measurement results of the pressing force. Furthermore, the travel controller 800 supplies electric power to the travel motors 320 to thereby forwardly rotate the travel wheels 325 that remain pressed against the friction-contact surfaces 216 of the rails 200. Thus, the carriage assembly 10 including the carriage frame 100 and the driving units 300 is moved in the forward direction. If the travel motors 320 and the travel wheels 325 are rotated reversely, carriage assembly 10 including the carriage frame 100 and the driving units 300 is moved in the reverse direction.

[75] Owing to the fact that the support wheels 510 and 511 of the support wheel units 500 roll in contact with the guide surfaces 213 and 214, the rail type transportation apparatus of the present invention can continue to travel in any one of different postures.

[76] Particularly, the travel brake device 330 and the pressing brake device ensure that the transportation apparatus of the present invention is stably kept in any one of different postures and is prevented from sliding or dropping even in the event of power failure, interruption of a commercial electric power, interruption of a motive power, circuit failure of the travel controller and normal stoppage of the transportation apparatus.

[77] With the transportation apparatus of the present invention, the driving units 300 and the support wheel units 500 of the carriage assembly 10 are moved along the rails 200. Therefore, there is no fear of breakage of the heat insulators 1 or the plywood layers thereof.

[78] Furthermore, there is no need to form a slit in each of the heat insulators 1 which would otherwise required in moving or driving the carriage assembly 10. Particularly, use of the rails 200 eliminates the need to bridge plywood lacking regions in the inter- insulator channels by use of separate connectors, thereby making it easy to attach the heat insulators 1.

[79] Although the carriage assembly 10 is moved by using a frictional force between the travel wheels 325 and the rails 200, the carriage assembly 10 may be driven by means of a rack-and-pinion mechanism.

[80] In addition, the travel controller 800 is capable of accurately feed-back controlling the moving speed of the rail type transportation apparatus based on the revolution number of the auxiliary wheels 600 detected by the travel encoder 700.

[81] While a preferred embodiment of the invention has been described hereinabove, the present invention is not limited to this embodiment. It is to be understood that various changes and modifications may be made without departing from the scope of the invention defined in the claims. Industrial Applicability

[82] The rail type transportation apparatus of the present invention can be advantageously used in the field of transporting various kinds of automated equipments for performing different tasks with respect to heat insulators attached to the inner wall surfaces of a ship cargo compartment.

Claims

[1] A rail type transportation apparatus for transporting various kinds of automated equipments for performing different tasks with respect to heat insulators attached to inner wall surfaces of a ship cargo compartment, comprising: a pair of rails removably secured to the heat insulators; a carriage assembly mountable to and movable along the rails; and a controller for controlling operations of the carriage assembly.

[2] The rail type transportation apparatus of claim 1, wherein the carriage assembly includes a carriage frame, a driving unit mounted to the carriage frame and provided with travel wheels, a pressing unit mounted to the carriage frame for pressing the travel wheels against the rails or moving the travel wheels away from the rails, a support wheel unit movable toward and away from the rails for engagement and disengagement with the rails and a travel brake device for stopping movement of the carriage assembly, and auxiliary wheels fixedly secured to a bottom surface of the carriage frame and adapted to roll along the rails.

[3] The rail type transportation apparatus of claim 2, wherein the carriage assembly further includes a travel encoder for detecting the revolution number of at least one of the travel wheels and the auxiliary wheels, the travel encoder adapted to supply the detected revolution number to the controller so that the controller can accurately control the moving speed of the carriage assembly.

[4] The rail type transportation apparatus of claim 1, wherein each of the rails has an upwardly inclined guide surface, a downwardly inclined guide surface and a friction-contact surface formed between the guide surfaces, the support wheel unit having support wheels adapted to make contact with the guide surfaces, the travel wheels adapted to make contact with the friction-contact surface.

[5] The rail type transportation apparatus of claim 4, wherein each of the rails has a bottom step portion formed on a lower surface of one side edge of each of the rails for making contact with a top corner portion of each of the heat insulators.

[6] The rail type transportation apparatus of claim 1, wherein the driving unit includes a travel motor for generating a torque in response to a control signal supplied from the controller and a power transmission mechanism for transferring the torque of the travel motor to the travel wheels.

[7] The rail type transportation apparatus of claim 6, wherein the travel brake device is adapted to hold or release a rotating shaft of the travel motor.

[8] The rail type transportation apparatus of claim 6, wherein the travel brake device is arranged around a driven shaft operatively connected to the rotating shaft of the travel motor through a bevel gear set.

[9] The rail type transportation apparatus of claim 1, wherein the pressing unit of the carriage assembly includes: a pressing motor for generating a torque in response to a control signal supplied from the controller; a first mounting bracket fixed to the carriage frame and adapted to support the pressing motor; a second mounting bracket fixed to the carriage frame in a position opposite from the first mounting bracket; a driving pulley attached to a rotating shaft of the pressing motor; a driven pulley operatively connected to the driving pulley; a double-threaded screw shaft fitted to the driven pulley at one end and rotatably supported at opposite ends by the first mounting bracket and the second mounting bracket; nut blocks threadedly engaged with the screw shaft; pressing members fixed to the nut blocks; and wheel carriages relatively movably connected to the pressing members and adapted to support the driving unit and the support wheel unit.

[10] The rail type transportation apparatus of claim 9, wherein the carriage assembly further includes pressure-regulating springs interposed between the pressing members and the wheel carriages.

[11] The rail type transportation apparatus of claim 9, wherein the pressing members and the wheel carriages are coupled to each other through a linear motion guide.

[12] The rail type transportation apparatus of claim 1, wherein the support wheel unit includes: a mounting base operatively connected to the pressing unit and moved together with the pressing unit; a cylinder portion fixedly secured to the mounting base; a rod extendibly fitted to the cylinder portion; and a wheel guide block attached to the rod, the wheel guide block having upper and lower oblique surfaces; and a plurality of support wheels rotatably mounted to the upper and lower oblique surfaces of the wheel guide block so that the support wheels can make contact with the rails.