JP2000198689A - Carrying lift - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reasonably prevent the generation of vibration and noise due to the looseness of a chain while always eliminating the looseness of the chain by interposing an elastic body in the compressed condition between a ratchet and a top surface of a main body case, and always energizing the ratchet upward. SOLUTION: When drawing of a chain 8 exceeds 1/2 of a pitch of a claw 73a of a ratchet 73, the ratchet 8 is moved upward by the restoring force of a coil spring 81 by a distance at 1/2 or more of the pitch of the claw 73a. The other push claw 72 in the non-latch condition is moved downward in relation to the ratchet 73 by a distance at 1/2 or more of the pitch, and latched with a claw 73a of a following ratchet 73. At the same time, the push claw 72 in the latch condition is moved downward in relation to the ratchet 73 by a distance at 1/2 or more of the pitch of the claw 73a so as to release the latch. With this structure, drawing to be generated in the chain 8 is always absorbed so as to optimally maintain the tensile force of the chain.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a transport lift for vertically moving a transported object.

[0002]

2. Description of the Related Art Conventionally, a conveyed article which is conveyed on a conveyer installed on a first floor is received, and the conveyed article is vertically raised and conveyed to a second floor.
Change to a conveyor mounted on the floor of the floor,
Alternatively, a transport lift has been developed which receives a transported object transported from a transport conveyor installed on the second floor, vertically lowers the transported object, and replaces the transported object on the transport conveyor installed on the first floor.

[0003] As shown in FIG. 9, the above-described conventional transport lift 100 includes a guide column 101 erected substantially vertically on a base 108 and moves vertically along the guide column 101. A guide body 102 slidably movable is provided. A mounting table 103 on which a conveyed object is mounted is mounted and supported on the guide body 102, and the mounting table 103 is configured to be slidably movable up and down along the guide column 101 together with the guide body 102. is there.

By the way, sprockets 104a and 104b are provided on the upper and lower portions of the guide column 101, respectively.
A drive motor 105 is connected to the upper sprocket 104a, and the sprocket 104a is configured to rotate in the forward and reverse directions by the rotation of the drive motor 105. A chain 106 is looped between the two sprockets 104a and 104b. One end of the chain 106 is fixed to the upper part of the guide body 102, and the other end of the chain 106 is fixed to the lower part of the guide body 102. It is connected to the attached and fixed chain tensioner 107.

The above-mentioned chain tensioner 107 is
A coil spring slidably fitted around the guide shaft is provided, one end of the coil spring is fixed to the guide body, and the other end of the chain 106 is connected to the other end of the coil spring. It is constituted by doing. That is, the chain 10 which is installed between the sprockets 104a and 104b and suspends the mounting table 103.
Numeral 6 maintains a state where tension is always applied by a coil spring provided in the chain tensioner 107 described above.

The transport lift 100 constructed as described above
Is configured to rotationally drive the drive motor 105 in a forward or reverse direction by a predetermined number of rotations. By the forward / reverse rotation of the drive motor 105, the chain 106 rotates by a predetermined distance in the ascending direction or the descending direction, and the mounting table 103 suspended by the chain 106.
Are configured to rise and descend by a predetermined stroke along the guide column 101.

[0007]

In the conventional transport lift 100 constructed as described above, the above-mentioned chain tensioner 107 is provided for the chain 106 for suspending the mounting table 103 for the transported object. The predetermined tension is maintained by constantly applying elastic tension by the contraction force of the coil spring. However, in the transport lift 100 described above, the chain tensioner 10
7, the tension is applied to the chain 106 elastically at all times, so that when the mounting table 103 on which the transported object is mounted is raised or lowered, the drive motor 105 is started to be driven, or conversely. When the driving is stopped, an inertial force is generated, and the coil spring instantaneously expands and contracts due to the inertial force. As a result, when the mounting table 103 is raised or lowered, unnatural vibration may occur.

An object of the present invention is to provide a transport lift as described above, which removes slack of a chain that lifts and lowers a mounting table, and at the same time, inertia generated when driving is started or stopped. An object of the present invention is to provide a function capable of rationally preventing vibration, noise, and the like caused by the chain being loosened by force.

[0009]

In order to solve the above-mentioned problems, a transport lift according to the present invention is provided with a guide body that slides along a guide column that is substantially vertically erected, and transports the guide body to the guide body. A mounting table for mounting objects is mounted and supported, the mounting table is supported so as to be able to move up and down along the guide column, and sprockets are provided at upper and lower portions of the guide column, and at least one of them is driven. A chain is connected between the two sprockets, and one end of the chain is connected to an upper portion of a guide body for mounting and supporting the mounting table, and the other end of the chain is connected to the sprocket. The chain tensioner is connected to a chain tensioner attached and fixed to the lower portion of the guide body. The chain tensioner includes a main body case attached to and fixed to the guide body. A ratchet is inserted so as to be able to slide substantially vertically, and the other end of the chain is fastened to the lower end of the ratchet. On the other hand, a push claw that is always elastically pressed and latched is provided to allow the ratchet to move upward, prevent the ratchet from moving downward, and penetrate the upper side of the main body case. An elastic body is elastically mounted in a compressed state between the ratchet and the upper surface of the main body case, and the ratchet is constantly urged upward.

According to the above-mentioned means, a guide body is installed on the guide column which is erected substantially vertically, and the guide body slides along the guide column. In addition, a mounting table for mounting a conveyed object is attached to and supported by the guide body. Therefore, the mounting table slides up and down along the guide support while being supported by the guide body. Further, a sprocket is provided on each of the upper and lower portions of the guide column, and a driving source is connected to at least one of the two sprockets so that the sprocket can be driven to rotate. Between the upper and lower sprockets, a chain is hung in an end shape,
One end of the chain is fixed to an upper part of a guide body on which a mounting table is mounted and supported. The other end of the chain is fixed to the lower end of a ratchet provided in a chain tensioner attached and fixed to a lower portion of the guide body.

The chain tensioner has a main body case which is fixedly mounted on a guide body of the mounting table, and through which the ratchet is inserted so as to be slidable substantially vertically. Further, inside the main body case, there are provided push claws which are always elastically pressed against claws formed side by side along one side surface of the ratchet. Then, when the pushing claw is always elastically pressed against the claw formed in parallel along one side surface of the ratchet and latched, for example, when the chain is elongated due to a load or an inertia force, A state in which the ratchet is allowed to move upward and the ratchet is prevented from moving downward. Further, between the ratchet inserted through the upper surface of the main body case and the upper surface of the main body case, an elastic body is elastically loaded in a compressed state, and the ratchet is constantly urged upward. is there. Therefore, when elongation (more than the ratchet claw pitch) occurs in the chain due to load inertia or the like, the ratchet moves upward, and the position of the claw on which the push claw is hooked is determined by one position. The chain is shifted to maintain the tension of the chain at a predetermined value.

According to a second aspect of the present invention, there is provided a transport lift in which a pair of push claws are installed in the main body case in parallel with each other, and the pitch of the claws between the push claws is set to the pitch of the ratchet claws. This is approximately 3/2 times.

[0013] In this case, the pitch of the claws between the two pressing claws, which are housed side by side in the main body case, is 3/2 times the pitch of the ratchet claws. One of the claws is hooked to the ratchet claw. That is, the double pressing claws are not simultaneously engaged with the ratchet claws. Further, the above-described latching relationship between the ratchet and the push claw prohibits the chain from shifting in the extending direction.

For example, in the case where the chain has an extension of 1/2 or more of the ratchet claw pitch due to a load, an inertial force, or the like, the ratchet moves upward to 1/2 or more of the ratchet claw pitch. In order to move the distance, the push nail which was in the hooked state
The push claw that has moved downward by two pitches or more and has been in the non-latching state has moved downward by 1/2 pitch or more relative to the ratchet, and is in a state of being latched by the pawl of the next ratchet. In addition, the push claw, which has been in the latched state, maintains the state in which it has moved to the approximate center of the ratchet claw. That is, in the chain tensioner configured as described above, the hooking pitch of the pushing claw on the ratchet can be reduced to 1/2 of the claw pitch, and as a result, the chain tension can be more finely adjusted.

According to a third aspect of the present invention, there is provided a transport lift in which a protection frame having a predetermined height surrounds a vertically extending guide column and a lifting and lowering range of a mounting table. At the lower stop position of the mounting table, an opening for taking in and out the conveyed article is opened, and the upper surface of the guide frame and the upper surface of the protective frame from which the raised mounting table protrudes are entirely opened.

[0016] In this case, the lifting range of the mounting table on which the conveyed object is placed can be surrounded by the protective frame, so that the danger of the worker being involved in the lifting of the mounting table can be avoided, and the lifting and lowering of the mounting table can be avoided. Even when a conveyed object placed on the mounting table collapses and falls, the conveyed object can be stored in a protective frame to prevent it from hitting surrounding machines or workers.
Further, at the lower stop position of the protective frame, an opening for taking in and out the conveyed object is opened, and the upper surface of the protective frame is fully opened, so that the conveyed object is loaded and unloaded on the mounting table. The work and the work of transferring the conveyed object on the mounting table moved to the ascending position to another conveyor can be performed smoothly.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. The transport lift shown in FIGS. 1 to 3 includes a base frame 4 mounted on a floor surface, and is mounted and supported with one side of the upper surface of the machine frame 4 having a guide column 1 standing upright. are doing. The guide support 1 is provided with a guide body 2 that slides along the guide support,
By mounting and supporting the mounting table 3 on which the transported object c is mounted horizontally with respect to the guide body 2, the guide body 2 and the mounting table 3 are configured to move up and down along the guide column 1. . In addition, the upper and lower parts of the guide post 1
The sprockets 5a and 5b are provided, respectively, and the drive motor 6 is connected to the lower sprocket 5b so that the sprocket 5b is rotatable forward and backward.

Between the two sprockets 5a and 5b,
One end of the chain 8 is connected to the upper part of the guide body 2 and the chain 8
Is connected to a chain tensioner 7 fixed to the lower part of the guide body 2. The drive motor 6 is not limited to the lower sprocket 5b, but may be installed on the upper sprocket 5a. However, as described above, the drive motor 6 is mounted on the floor of the first floor. By installing the drive motor 6 on the lower sprocket 5b side close to the surface, maintenance work of the drive motor 6 can be easily performed.

As shown in FIG. 1 and FIG.
Is formed as a substantially rectangular frame in plan view using an angle material or the like. An inner frame 4a is provided inside the machine frame 4 and height-adjustable adjusters 4c are provided at four corners on the lower surface of the inner frame 4a. By adjusting the heights of these adjusters 4c respectively, The machine frame 4 is configured to be installed horizontally on the floor. A substantially box-shaped box frame 4b, which is open on both left and right sides, is attached to and fixed to the upper surface on the back side of the inner frame 4a. The box frame 4b has a function as a case for mounting and supporting the lower end portion of the guide column 1 and accommodating the drive motor 6 and its speed reduction mechanism 6a.

As shown in FIG. 4, the guide column 1
Is a substantially quadrangular prism-shaped hollow body having a predetermined height, and a lower end portion thereof is bolted to a box frame 4b provided on the back side of the machine frame 4 so that the rear surface of the machine frame 4 It stands upright on the side. The height of the guide column may be arbitrarily changed in accordance with the elevating stroke of the mounting table 3. However, in the case of the guide column 1 of this embodiment, the height is set to approximately 2.4 m. Along the edges corresponding to the left and right corners on the front side of the guide column 1, a guide rail 11 projecting toward the left and right sides is integrally formed (FIG. 3). On the other hand, along the edges corresponding to the right and left corners on the back side of the guide column 1, nut receiving grooves 12 each having a substantially C-shaped cross section are formed so as to protrude toward both left and right sides. Along with nuts for mounting parts along
It is configured to be slidable along the inside of the groove 12, so that the mounting part can be bottle-stopped at an arbitrary position.

A pair of left and right sprocket support plates 58 are mounted and supported on the upper end of the guide column 1 in a state where they face each other at appropriate intervals, and the upper sprocket 5a is located between the two sprocket support plates 58. It is rotatably supported. On the other hand, a drive motor 6 with a speed reducer 6a is installed horizontally inside a box frame 4b for mounting and supporting the lower part of the guide column 1, and its output shaft 6b causes the lower sprocket 5b to be paired with the upper sprocket 5a. Are supported so as to be able to be driven forward and reverse (FIG. 2). The lower sprocket 5b is located just below the upper sprocket 5a, and the outer peripheral portions of the front sprockets 5a and 5b project toward the front of the guide column 1.

As described above, an endless chain 8 is provided between the upper and lower sprockets 5a, 5b installed at the upper and lower ends of the guide column 1. The chain 8 is for suspending the guide body 2 and the mounting table 3 slidable up and down along the guide column 1 so as to be able to move up and down. The chain 8 is hung between the two sprockets 5a and 5b, and has one upper end. Chain tensioner 7 having its portion fixed to the upper portion of the guide member 2 and the other lower end portion provided at the lower portion of the guide member 2.
(Fig. 1). That is, in the chain 8, the rear side of the passage passes through the substantially central portion of the hollow portion of the guide column 1, and the front side passes through the central portion of the front side of the guide column 1 (FIG. 2).

The guide body 2 which slides along the guide column 1 is formed in a substantially U-shape in plan view, and its opening is fitted to the front surface of the guide column 1 with an appropriate gap therebetween. Installing. A pair of large and small guide rollers 20a is provided at upper and lower ends on both left and right sides of the guide body 2 opening.
20b is rotatably supported at predetermined intervals. In other words, two upper and lower guide rollers 20a and 2 (four on each side) are provided on both left and right side surfaces in the opening of the guide body 2.
0b is provided. And each of these guide rollers 20
a and 20b, the guide rails 11 protruding along the left and right sides of the guide column 1 are inserted vertically, and sandwiched between the two guide rollers 20a and 20b. A pair of left and right guide rails 1
It is configured to slide vertically while guiding along 1.

As described above, the pair of large and small guide rollers 20a, 20b provided on the upper side of the guide body 2 is such that the large-diameter guide roller 20a is located on the back side of the guide rail 11 and the small-diameter guide roller 20a, 20b. Guide roller 20b
To the front of the guide rail. In addition, the one provided on the lower side of the guide body 2 has a large-diameter guide roller 20a disposed on the front side of the guide rail 11 and a small-diameter guide roller 20b on the rear side of the guide rail 11, contrary to the above case. (FIG. 3). The above arrangement of the guide rollers 20a and 20b is a consideration for allowing the large-diameter guide roller 20a to support most of the load applied when the mounting table 3 is horizontally mounted and supported below the guide body 2.

As described above, a mounting table 3 for mounting a conveyed object c is horizontally mounted and supported below the guide body 2 which is slidably mounted and supported along the guide column 1. The mounting table 3 is provided with a pair of left and right support frames 31 which are formed in a substantially crank shape when viewed from the side, and one end of each of the support frames 31 is attached and fixed to the lower portions of the left and right side surfaces of the guide body 2. A belt conveyor 32 for transporting the article c in the left-right direction on the other side of the two support frames 31 extending horizontally toward the front side of the guide body 2.
Are mounted horizontally and fixed on the support frames 31 (FIGS. 1 and 2). Therefore, the mounting table 3 mounted and supported on the guide body 2 as described above moves up and down along the guide column 1 together with the guide body 2 with the conveyed article c placed on the belt conveyor 32.

A fixing body 21 is attached and fixed to the upper end of the opening of the guide body 2, and a fixing bolt 22 is vertically inserted into the center of the fixing body 21 to vertically attach the fixing body 21. Nuts are fixed against. As described above, the upper end of the chain 8 bridged between the upper and lower sprockets 5a and 5b is connected to the upper end of the fixing bolt 22 and fastened. On the other hand, the other end of the lower side of the chain 8 is connected to a chain tensioner 7 installed below the guide body 2. Therefore, the guide body 2 and the mounting table 3
Is suspended from above by a chain 8, and the guide support 1
The drive of the drive motor 6 installed in the lower part of the
Is rotated forward or backward, so as to move up and down while being guided along the guide column 1.

FIG. 3 shows a chain tensioner 7 for fastening the lower end of the chain 8. The chain tensioner 7 absorbs the elongation of the chain 8 and constantly maintains appropriate tension. The chain tensioner 7 is attached to and fixed to the attachment member 23 of the guide body 2. It is composed of a ratchet 73 inserted vertically slidably and a pair of push claws 72 provided inside the main body case 71. The main body case 71
The bolt 91 is fixed on a mounting member 23 provided between the left and right sides of the lower portion in the opening of the guide body 2. The opening provided on the front surface of the main body case 71 is closed by a cover plate 74, and is detachably attached to the main body case 71 by two bolts 75c. Further, in addition to the bolt 75c, two support bolts 75a and 75b are screwed into the cover plate 74 at predetermined intervals in the vertical direction, and the ends thereof are projected into the main body case 71. (Fig. 3).

A liner 76 is provided inside the main body case 71.
A pair of pushing claws 72 which are fitted in the insides a and 76b and supported so as to be slidable in the axial direction are provided side by side. Double press claw 7
Numeral 2 is a cylindrical body having a hook claw 72a formed at a tip thereof.
The shaft bolt 7 protruding into the main body case 71 in a state of being fitted inside the liners 76a and 76b as described above.
The base ends of the hollow portions 75a 'and 75b' are fitted to the distal ends of 5a and 75b. The hollow portions 75a ', 75
The coil springs 77 are elastically mounted in the b ′ in a compressed state, and the resilient force of the coil springs 77 causes the hooking claws 72 a at the tips of the both pressing claws 72 to move.
The ratchet 73 penetrates the inside of the ratchet 73 so as to always elastically press and contact the pawl 73a (FIG. 5).

On the other hand, the ratchet 73 has a substantially shaft-like outer shape, is inserted into a fitting hole 78 formed in the upper and lower surfaces of the main body case 71, and is slidably supported in the vertical direction. The other lower end of the chain 8 is fixed to the portion. The ratchet 73 has a large number of claws 73a arranged in a line along one side surface on the front side. As shown in FIG. 6, each of the claws 73 a of the ratchet 73 described above is connected to each other by a slant surface 73 a ″ between hooking surfaces 73 a ′ formed at regular intervals, so that a saw in a side view is formed. It is shaped like a blade. On the other hand, the double pressing claw 72 described above
The latching claw 72a formed at the tip of the ratchet 7
The third pawl 73a is constantly pressed by the repulsive force of the coil spring 77, and this pawl 72a is configured to be engaged with the pawl 73a located above the row of pawls 73a of the ratchet 73 ( (Fig. 5).

The latching relationship between the pawl 73a of the ratchet 73 and the pawl 72a of the double pressing pawl 72 is such that the pawl 73a 'of the pawl 73a of the ratchet 73 faces downward. Also,
The engaging surface 72a 'of the engaging claw 72a of the pressing claw 72 is configured to be abutted and engaged with the engaging surface 73a' while facing upward. In this state, the inclined surface 73 of the pawl 73a of the ratchet 73
a ′, the inclined surface 72 of the locking claw 72 a of the double pressing claw 72
a '' is in close contact. Thereby, the pushing claw 7
2 is constantly pressed against the inclined surface 73a ″ of the claw 73a and slides, and the hooking surface 72 of the two claws 72a, 73a is
The a 'and 73a' come into contact with each other and are hooked to prevent the ratchet 73 from moving downward. That is, even if tension is applied from the other lower end of the chain 8 fixed to the lower end of the ratchet 73, the ratchet 73 does not fall down.

Further, between the nut 79 screwed and fixed to the upper part of the ratchet 73 and the upper surface of the main body case 71, a coil spring 81 is elastically mounted in a compressed state. Ratchet 7 penetrated
3 is always urged upward.
However, the tension applied to the chain 8 is sufficiently larger than the urging force of the coil spring 81, and therefore, the claw 73a of the ratchet 73 is normally used.
And the inclined surface 72a '' of the hooking claw 72a of both push claws 72 is pressed to maintain the hooked state. Therefore, the upward movement of the ratchet 73 is allowed only when the chain 8 is stretched due to, for example, a load or an inertial force.
After the engaging position between the pawl 73a and the pushing pawl 72 is shifted downward, the ratchet 73 is prevented from moving downward.

The pawl 73a of the ratchet 73 described above.
And the locking claws 72a of the double pressing claws 72, the sliding between the inclined surfaces 72a '' and 73a '' which are joined by the upward movement of the ratchet 73 causes the double pressing claws 72 to slide. Can be retracted by the compression of the coil spring 77, so that the ratchet 73 can be slid upward. Further, in the present embodiment, the coil spring 81 is used as an elastic body to be elastically mounted between the nut 79 and the upper surface of the main body case 71. However, the above-mentioned elastic body is formed between the upper part of the ratchet and the upper surface of the main body case 71. Any existing elastic body may be used as long as it can be elastically interposed and constantly urge the ratchet upward.

In the chain tensioner 7 constructed as described above, the pitch between the hooking claws 72a of the double pressing claws 72 provided in a state of being juxtaposed in the main body case 71 is adjusted by the claws 73a juxtaposed to the ratchet 73. Is set to be approximately 3/2 times the pitch of As described above, the double pressing claw 7
By setting the pitch between the two hooking claws 72a to be 3/2 times the pitch of the hooks 73a of the ratchet 73, one of the hooks 72a of the double pressing claws 72 is always the hook 73a of the ratchet 73. (FIG. 6). Therefore, the latching claw 72a of the double pressing claw 72 is
Is not locked at the same time, and one of the push claws 72 is always locked to the claw 73a of the ratchet 73. The latching relationship prevents the ratchet 73 from moving downward,
Prevents the chain from shifting in the direction of extension.

Therefore, in the chain tensioner 7 constructed as described above, if, for example, an extension of 1/2 or more of the pitch of the claws 73a of the ratchet 73 occurs in the chain 8 due to a load or an inertia force, the coil spring 8
The restoring force of 1 causes the ratchet 73 to move upward by a distance equal to or more than の of the pitch of the pawl 73a.
Move downward by 1/2 pitch or more relative to the claw 73a. At the same time, the other push claw 72 in the non-latched state moves downward by a half pitch or more relative to the claw 73 of the ratchet 73 to move the next (lower) ratchet 73. The hook 73a is hooked. That is, the chain tensioner 7 can reduce the hooking stroke of the ratchet 73 to half of the pawl pitch of the ratchet 73. As a result, the tension of the chain 8 is adjusted in finer units. It is possible to always maintain the tension of the chain 8 at an appropriate level. The chain tensioner 7 uses two latching claws 72a to set the latching stroke of the ratchet to 1/2 pitch. However, the above chain tensioner
The hook stroke can be set to 1/3 pitch by providing three hook claws. That is, by using the n hooks, the hook stroke can be set to 1 / n pitch.

Next, the operation of the transport lift configured as described above will be described. In the above-described transport lift, for example, the machine frame 4 is installed on the first floor, and the machine frame 4
It is installed so that the upper part of the guide column 1 erected on the floor protrudes on the second floor. On one side of the transport lift installed on the first floor, a transport conveyor d1 is installed so as to be close to one end of the conveyor 32 provided on the mounting table 3 of the transport lift. The conveyed article c is configured to be conveyed onto the conveyor 32 of the mounting table 3 stopped at the lower stop position (FIG. 2). On the other hand, on the second floor, when the mounting table 3 is moved up to the upper stop position of the guide column 8, a carrying conveyor d2 for unloading is provided so as to be close to the other end of the conveyor 32 of the mounting table 3. Has been installed.

Therefore, the conveyor 3 of the mounting table 3 which stops at the lower stop position from the conveyor d2 installed on the first floor.
When the conveyed article c is loaded onto the chain 2, the drive motor 6 is driven to rotate in the normal direction, and the chain 8 bridged between the upper and lower sprockets 5a and 5b is rotated in the ascending direction, and The suspended guide body 2 and mounting table 3 rise while being guided along the guide column 1.

A sensor f1 is attached to one side of the guide body 2. At predetermined locations on the upper and lower sides of one side of the guide column 1, there are installed sensing sensors f2 and f3 that the sensor f1 senses when approaching. That is, when the guide body 2 and the mounting table 3 approach the upper stop position of the guide column 1, the sensor f1 provided on the guide body 2 is detected by the reception sensor f3 provided above the guide column 1, Based on this, the drive motor 6 is decelerated and stops when the guide body and the mounting table 3 reach the upper stop position.

When the guide body 2 and the mounting table 3 stop at the upper stop position as described above, the conveyors 32 and 2 of the mounting table 3
The ends of the conveyors d2 installed on the floor are close to each other at the same level, and at this moment, the conveyor 32 of the mounting table 3 is operated, and the article c placed on the conveyor 32 is moved. It is carried into the start end of the conveyor d2 on the second floor and is conveyed to the next destination.

After the conveyed article c is sent out from the conveyor 32, the drive motor 6 is driven to rotate in the reverse direction, the chain 8 rotates in the descending direction, and the guide body 2 stopped at the upper stop position. , The mounting table 3 descends along the guide column 1. Then, the descending guide body 2 and the mounting table 3
However, when approaching to the lower stop position of the guide column 1, the sensor f1 installed on the guide body 2 detects the sensor f2 provided below the guide column 1, and based on this, the drive motor 6 decelerates. Then, when the guide body 2 and the mounting table 3 reach the lower part stop position, they stop.

The transport lift repeatedly transports the article c from the transport conveyor d1 on the first floor to the transport conveyor d2 on the second floor while repeatedly performing the above-described operation steps. In addition, contrary to the above-described case, the transport lift can repeatedly transport the articles c from the transport conveyor d2 on the second floor to the transport conveyor d1 on the first floor. Furthermore, the transport path using the transport lift has various variations. For example, when carrying goods carried in from the right side of the first floor to the right side on the second floor, or carrying goods carried in from the left side of the first floor to the left on the second floor, The transport pattern may be arbitrarily changed, such as transporting the in-conveyance article from the left side of the first floor to the right side on the second floor.

When the above-described transfer lift is repeatedly operated, the load of the guide body 2, the mounting table 3, and the conveyed object c mounted on the mounting table 3 is applied to the chain 8, and in particular, the load of the mounting table 3 is increased. The load is doubled by the inertia generated when the ascent of the ascent starts and when the descent stops. When such use is performed for a long period of time, the chain 8 starts to gradually elongate.

When the elongation of the chain 8 becomes half or more of the pitch of the pawls 73a of the ratchet 73, the ratchet 73 is moved upward by the restoring force of the coil spring 81 and the pitch of the pawls 73a becomes one of the pitches. The other push claw 72, which has been in the non-latched state, moves downward by a half pitch or more relative to the ratchet 73 to catch on the pawl 73a of the next ratchet 73. It will be in a stopped state. At the same time, one of the pushing claws 72 in the hooked state moves downward relative to the ratchet 73 by a half pitch or more of the pawl 73a to be in the non-latching state. That is, in the chain tensioner 7, the elongation of the chain 8 becomes equal to or more than １ ／ of the pitch of the claws 73a.
Each time the ratchet 73 moves upward by that amount,
The latching of the ratchet 73 to the pawl 73a is performed by the double pressing pawl 7.
2 alternately, so that the chain 8
The chain tension is constantly absorbed to maintain the tension of the chain at an appropriate value. In addition, the chain 8 once loosened
Does not return to the original position due to the engagement between the ratchet and the push 72.

As shown in FIG. 8, the transport lift may be surrounded by a protective frame 9 around the elevating range of the guide column 1 and the mounting table 3. The protective frame 9 is a hollow and substantially rectangular column-shaped cage body that stands up by being placed along the outer peripheral portion of the machine frame 4 and stops at the upper stop position from the machine frame 4. The mounting table 3 has a height just below the mounting table 3. An opening 91 is provided at one side of the protective frame 9 at a position corresponding to the lower stop position of the mounting table 3, and an opening 91 for taking in and out a conveyed object is provided. An opening is formed, and the upper part of the guide column 1 and the mounting table raised to the upper stop position project from the opening 92. The transport lift equipped with the protective frame 9 as described above prevents the worker from being caught in the elevating of the mounting table 3, and even when the conveyed object placed on the mounting table 3 collapses and falls during the elevating operation. Then, the conveyed object can be stored in the protective frame 9 so as to prevent the conveyed object from hitting the surrounding machines and workers. The transport lift of the present invention preferably uses a chain as a lift for suspending the mounting table. However, other than the chain, for example, a wire or a high-strength belt may be used.

[0044]

As described above, in the transport lift of the present invention, a guide body is provided so as to be slidable along a guide column, and a mounting table for a transported object is mounted and supported on the guide body. A sprocket is provided at each of the upper part and the lower part, and a driving source is connected to at least one of the sprockets,
A chain is installed between the two sprockets, and one end of the chain is connected to the upper part of the guide body, and the other end of the chain is connected to a chain tensioner attached and fixed to the lower part of the guide body. Tensioner
Comprises a main body case which is attached to and fixed to the guide body and penetrates the ratchet so as to be substantially vertically slidable. Inside the main body case, a push claw which constantly presses the ratchet claw elastically is provided. Thus, while allowing the upward movement of the claw rack and preventing the downward movement of the ratchet, the ratchet was elastically mounted between the ratchet inserted through the upper surface side of the main body case and the upper surface of the main body case. By elastic body,
The ratchet is always urged upward.

Therefore, when the chain for suspending the guide body elongates more than the ratchet claw pitch due to, for example, a load force or an inertia force generated during operation, the ratchet and the push claw provided in the chain tensioner are used. , The ratchet can be moved upward, the hooking position between the push claw and the ratchet can be shifted by one pitch, and a proper tension can always be secured in the chain. In addition, by utilizing the latching relationship between the ratchet and the push claw as described above, the return of the ratchet (elongation of the chain) can be reliably absorbed. Compared with the one equipped with a chain tensioner composed of a coil spring, when raising or lowering the mounting table on which the conveyed object is mounted, the inertia force or load generated when starting driving or conversely, when driving is stopped The generation of unnatural vibration or noise by the force can be effectively prevented.

According to a second aspect of the present invention, in the transport lift, a pair of push claws are provided inside the main body case in parallel with each other, and the pitch of the claws between the push claws is set to the pitch of the ratchet claws. Since it is approximately 3/2 times, for example, when the chain is stretched by 1/2 or more of the ratchet claw pitch due to a load, inertia force, or the like, the ratchet is raised upwardly. 1 / of the nail pitch
Move two or more distances. As a result, the push claw in the latched state moves downward by a half pitch or more relative to the ratchet, and the push claw in the non-latched state moves 1 / relatively to the ratchet. It moves downward by two pitches or more and is in a state of being hooked on the next ratchet claw. Therefore, the chain tensioner provided in the transport lift of the present application can reduce the elongation stroke until the elongation of the chain is absorbed to half of the ratchet claw pitch, and as a result, can finely adjust the chain tension. To maintain optimal tension.

According to a third aspect of the present invention, there is provided a transport lift in which a guard frame surrounds the guide column and the ascending / descending range of the mounting table, and an opening through which a conveyed article is taken in and out of the side of the protective frame at a lower stop position of the mounting table. And the upper surface of the protective frame from which the upper part of the guide column protrudes is fully open, so the protective frame surrounds the lifting range of the mounting table on which the load is placed. Can be. As a result, it is possible to avoid the danger of the worker getting caught up and down of the mounting table, and to prevent the transferred object placed on the same mounting table from falling and falling during the raising and lowering of the mounting table. And can be prevented from hitting surrounding machines and workers. In addition, at the lower stop position of the above-described protective frame, an opening for taking in and out the conveyed article is opened, and the upper surface of the protective frame is fully opened, so that the protective frame is attached to the transport lift as described above. Even if it is provided, the work of loading and unloading the load on the mounting table and the work of reloading the load on the mounting table moved to the ascending position to another transfer conveyor can be performed smoothly without any trouble. .

[Brief description of the drawings]

FIG. 1 is a side view showing a transport lift embodying the present invention.

FIG. 2 is a front view of the transport lift.

FIG. 3 is a side view showing a guide body and a chain tensioner portion of the transport lift with a part cut away.

FIG. 4 is a longitudinal plan view showing a guide column and a guide body.

FIG. 5 is a side view showing the chain tensioner partly cut away, and a longitudinal sectional view showing the case body part in an enlarged manner.

FIG. 6 is a longitudinal sectional side view showing a process in which a ratchet slides upward due to slack of a chain.

FIG. 7 is a vertical cross-sectional side view showing a state in which the slack of the chain has reached の or more of the nail pitch and the lower push nail has been hooked to the next nail.

FIG. 8 is a side view showing a transport lift provided with a protective frame with a part thereof omitted.

FIG. 9 is a side view showing a conventional transport lift.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Guide pillar 2 ... Guide body 3 ... Mounting table 5a, 5b ... Sprocket 6 ... Drive motor 7 ... Chain tensioner 8 ... Chain 9 ... Protective frame 71・ ・ ・ Main body case 72 ・ ・ ・ Push nail 72a ・ ・ ・ Hook nail 73 ・ ・ ・ Ratchet 73a ・ ・ ・ Claw 81 ・ ・ ・ Coil spring 91 ・ ・ ・ Opening part 92 ・ ・ ・ Opening

Claims (3)

[Claims] 1. A guide body which slides along a guide column which is provided substantially vertically, a mounting table on which a conveyed object is mounted is mounted and supported on the guide body, and the mounting table is mounted on the guide column. The guide column is supported so as to be able to move up and down, and a sprocket is provided at each of the upper and lower portions of the guide column, a drive source is connected to at least one of the sprockets, and a chain having ends is hung between the two sprockets. The chain tensioner is formed by connecting one end of a chain to an upper portion of a guide body for mounting and supporting the mounting table, and connecting the other end of the chain to a chain tensioner mounted and fixed to a lower portion of the guide body. -Has a main body case attached to and fixed to the guide body, and a ratchet is inserted through the main body case so as to be able to slide substantially vertically,
The other end of the chain is fixed to the lower end thereof, and a push is always elastically pressed against a hook formed in parallel with one side of the ratchet in the main body case. With the claws inside, allowing upward movement of the ratchet, preventing downward movement of the ratchet, between the ratchet penetrated to the upper surface side of the main body case and the upper surface of the main body case, Elastic body is loaded in the compressed state,
A transport lift that constantly biases the ratchet upward. 2. A pair of push claws are installed in the body case in a state of being juxtaposed, and a pitch of the claws between these push claws is set to approximately 3/2 times a pitch of the ratchet claws. Item 4. The transport lift according to Item 1. 3. A protection frame having a predetermined height surrounds a guide column and a lifting frame of a mounting table which are set up substantially vertically, and a transported object is located at a lower stop position of the mounting table on a side surface of the protection frame. 3. The transport lift according to claim 1, wherein an opening for taking in and out of the guide frame is opened, and the upper surface of the guide post and the upper surface of the protective frame from which the raised mounting table protrudes are entirely opened.