JP5792457B2 - Traveling position detection device - Google Patents

Description

  The present invention relates to a traveling position detection device for a mobile carriage in an automatic warehouse.

  In the automatic warehouse, a position detection device including a rotary encoder is provided in order to detect the traveling position of the moving carriage. In this case, the simplest structure is that a moving carriage is provided with a detection roller that rolls on the rail as it travels, and the rotation of this roller is counted as a minute pulse by a rotary encoder. Is calculated.

  However, the roller may move away from the rail due to unevenness or deformation of the rail, or swinging of the moving carriage. For this reason, the travel position can be accurately detected with a simple structure in which the roller is applied to the rail. There were cases where it was not possible.

  Therefore, for example, there is a traveling position detection device disclosed in Patent Document 1 as a traveling position detection device with improved detection accuracy.

  In this traveling position detection device, a lifting bracket that is pushed vertically downward by two springs is attached to a fixed bracket provided on a movable carriage, and a swinging bracket that rotates like a seesaw is attached to the lifting bracket. The swing bracket is provided with a pair of front and rear rollers, and the interlocking shaft that rotates in synchronization with both rollers via a gear is connected to the rotor of the rotary encoder.

  This traveling position detection device improves the detection accuracy of the traveling position because at least one of the pair of rollers is in contact with the rail even if the rail has unevenness or bending deformation.

Japanese Patent No. 3595951

  In the conventional traveling position detecting device described above, there is a need to manually lift the pair of rollers from the rails for the reason of removing the deposits on the pair of rollers.

  At this time, it is necessary to lift the elevating bracket against the two springs in good balance in parallel and vertically upward, so that the two springs are easily twisted during lifting, and it is extremely difficult to perform smoothly.

  Therefore, as a result of at least one of the two springs being twisted when the lifting bracket (the pair of rollers) is lifted, the durability of the position detection device itself deteriorates due to the deterioration of the characteristics such as the elastic force of the spring, and with time changes There was a problem that detection accuracy deteriorated.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to obtain a traveling position detection device that can maintain high detection accuracy over a long period of time.

According to a first aspect of the present invention, there is provided a travel position detecting device for use in a mobile trolley in an automatic warehouse, which is freely rollable on a rail surface so as to rotate as the mobile trolley travels. A plurality of rollers in contact with each other, and the plurality of rollers are arranged so as to contact the same surface of the rail and to be separated from each other in the longitudinal direction of the rail, and through a gear group that is held in mesh with each other. An interlocking shaft that rotates in synchronization with the plurality of rollers, a rotary encoder that detects the rotation of the interlocking shaft, and a spring that can rotate in a seesaw shape when viewed from a direction orthogonal to the rail. A swing bracket urged downward by the plurality of the plurality of low-loading rails so as to rollably contact the surface of the rail on both sides of the swing bracket with the rotation center therebetween. And a rotation mechanism capable of moving the plurality of rollers away from the rail by lifting the swinging bracket with a rotation operation along a first rotation direction about a predetermined rotation axis. The first rotation direction is set in a direction opposite to a second rotation direction that is a rotation direction applied to the rotation mechanism by the biasing force of the spring, and the first rotation direction by the rotation mechanism , The moment arm is provided between the predetermined rotating shaft and the swing bracket.

According to the first aspect of the present invention, the plurality of rollers can be separated from the rail by lifting the swinging bracket by the rotation mechanism along the first rotation direction around the predetermined rotation axis by the rotation mechanism. Is possible. At this time, the first rotation direction is set in a direction opposite to the second rotation direction, which is a rotation direction applied to the rotation mechanism by the biasing force of the spring.

  Therefore, since the lifting operation of the lifting bracket can be performed by a rotating operation using the moment arm, the spring for urging the swinging bracket downward is not twisted during the lifting operation, and the lifting bracket can be smoothly performed.

  As a result, the running position detection device according to the present invention described in claim 1 has high durability without being affected by reliably avoiding the possibility of deteriorating the characteristics of the spring by the lifting operation of the swing bracket. There is an effect that the detection accuracy can be maintained.

It is a perspective view which shows the outline of the one end part of the automatic warehouse where the position detection apparatus of this Embodiment is used. It is a fracture perspective view showing the outline of a hangar. It is a top view of a mobile trolley. It is a top view of the position detection apparatus of this Embodiment. FIG. 5 is a VV sectional view of FIG. 4. FIG. 6 is a sectional view taken along line VI-VI in FIG. 5. FIG. 7 is a sectional view taken along line VII-VII in FIG. 5. It is explanatory drawing which shows the effect | action of the position detection apparatus of this Embodiment. It is sectional drawing corresponding to FIG. 6 in the conventional position detection apparatus.

  FIG. 1 is a perspective view showing an outline of one end portion of an automatic warehouse in which a traveling position detection device according to an embodiment is used. FIG. 2 is a perspective view showing a partial outline of the automatic warehouse. The automatic warehouse includes a hangar 1 and a loading / unloading unit 2 provided in the vicinity of one end of the hangar 1.

(Overview)
The hangar 1 has a large number of shelves 3 arranged in multiple stages on both sides of the passage, a large number of pairs of rails 4 disposed horizontally corresponding to the shelves 3 of each stage, and a movement that travels on each rail 4. A dolly 5 is provided. Each shelf 3 is supported by an inner vertical frame 6 positioned on the passage side, an outer vertical frame 7 positioned on the outer side, and a horizontal rear frame 8 that is fixed between the adjacent outer vertical frames 6.

  The rail 4 is fixed to the inner vertical frame 6, and the inner vertical frame 6 and the shelf board 3 of each step are set to the same height. Adjacent outer vertical frames 7 are reinforced with braces 9.

  The loading / unloading unit 2 includes a shelf conveyor 10 disposed in a state extending from the shelf 3 of each stage, and a pair of lift conveyors 12 that freely move up and down along the columns 11. Each lift conveyor 12 is arranged to extend in a straight line with the shelf conveyor 10 in plan view.

  In addition, in the vicinity of the loading / unloading unit 2, a loading / unloading conveyor 13 that extends in series with each lift conveyor 12 in plan view is provided. As indicated by a one-dot chain line in FIG. 1, a transport conveyor 14 may be provided on the upper stage. Reference sign W indicates a package.

  FIG. 3 is a plan view of the movable carriage 5. As shown in the figure, the movable carriage 5 includes a body frame 16 having a rectangular shape in plan view formed of mold steel or the like, a pair of front and rear wheels 18 connected by an axle 17, and a motor 19 for driving one wheel 18. , Fixed and movable picking devices 20 and 21 extending in a direction orthogonal to the traveling direction, and a motor 22 for moving and adjusting the movable picking device 21 toward the fixed picking device 20 are provided. The motors 19 and 22 are attached to the upper surface plate 23.

  Both picking devices 20 and 21 have a built-in reciprocating movement arm (not shown) that can be moved back and forth toward the shelf 3. A picker 24 is attached to be horizontally rotatable. The picking devices 20 and 21 are provided with a mounting plate 25 on which the load W is placed, and the mounting plates 25 partially overlap each other.

(Position detection device)
Further, a position detection device 27 according to the present embodiment is provided in the vicinity of the motor 19 and the wheels 18 in the movable carriage 5. This point will be described with reference to FIG. 4 is a plan view of the position detection device 27, FIG. 5 is a cross-sectional view taken along the line VV in FIG. 4, FIG. 6 is a cross-sectional view taken along the line VI-VI in FIG. FIG. 8 is an explanatory view showing the operation.

  The position detection device 27 is configured such that one end of a pair of holder arm plates 59 can rotate on a support shaft 60 for a rotating shaft placed on a base plate 28 provided on an upper surface plate 23 of the main body frame 16 of the movable carriage 5. Installed on. Hereinafter, this point will be described in detail.

  As shown mainly in FIGS. 4 and 5, a rotary shaft 58 is rotatably inserted into a hollow shaft (not shown) provided in the rotary shaft support base 60, and a pair of holder arms are provided at both ends of the rotary shaft 58. One end of each plate 59 is fixed by a bolt 57. Therefore, the holder arm plate 59 is rotatably provided with the rotation shaft 58 as the rotation shaft.

  The other end of the holder arm plate 59 is integrally formed with the elevating bracket 31 while being in close contact with the upper end of the elevating bracket 31 from the upper side of the side. The elevating bracket 31 has a U-shaped downward opening.

  A pair of left and right swing brackets 36 formed in an inverted T shape in a side view is attached to the elevating bracket 31 by a pair of hollow shafts 37 so as to rotate in the shape of a seesaw around its front and rear central portions. ing.

  A pair of rollers 38 that are in contact with the rail 4 are rotatably attached to the left and right swing brackets 36 by shafts 39 on both front and rear sides with the rotation center therebetween. Both rollers 38 are integrally provided with a main driving gear 40, while an interlocking shaft 41 that is rotatably fitted to the hollow shaft 37 is integrally provided with a driven gear 42 that meshes with the main driving gear 40 (see FIG. 7). ). Although not shown in these drawings, a rubber layer is provided on the outer peripheral surface of the roller to increase friction.

  Furthermore, a bracket 43 having a U-shape in plan view protruding toward the movable carriage 5 is fixed to the elevating bracket 31, and a rotary encoder 44 is attached to the bracket 43, and the rotor 44 a and the interlocking shaft 41 of the rotary encoder 44 are attached. Are connected by a coupling 45.

  A pair of spring mounting portions 51 are hooked on both side surfaces of the bracket 43 in the vicinity of the U-shaped opening in a plan view so that the spring can be mounted, and in the vicinity of the side surface of the bracket 43 on the rotary shaft support base 60. A pair of spring mounting portions 52 is provided so that the Y direction matches the pair of spring mounting portions 51 in plan view. A pair of springs 50 is provided between the pair of spring mounting portions 51 and the pair of spring mounting portions 52.

  In the above configuration, the front and rear rollers 38 move upside down, and a downward force is applied to the liftable bracket 31 by the biasing force accompanying the elastic restoring force of the spring 50, so as shown exaggeratedly in FIG. For example, even if one of the rollers 38 floats from the rail 4 due to the rail 4 being depressed or deformed, the other roller 38 is pressed against the rail 4 in reverse. Accordingly, since at least one of the rollers 38 contacts the rail 4, the traveling position of the movable carriage 5 can be accurately detected.

  By the way, it can be said that the relative height relationship between the wheel 18 and the rail 4 is constant regardless of the deformation of the rail 4 because the wheel 18 of the movable carriage 5 always hits the rail 4. For this reason, when the position detection device 27 is arranged in the vicinity of the wheel 18 as in the present embodiment, the relative height between the position detection device 27 and the rail 4 can be made substantially constant. The state where 38 is applied to the rail 4 can be held more reliably, and the detection accuracy can be further improved.

(Lifting operation of the lifting bracket 31)
In the position detection device 27, when no force is applied to the liftable bracket 31 from the outside, the force is applied to the holder arm plate 59 in the rotational direction R2 by the biasing force of the spring 50. The force is applied downward.

  In the travel position detection device 27 of the embodiment, it is necessary to lift the elevating bracket 31 manually to separate the pair of rollers 38 from the surface of the rail 4 in order to remove the deposits on the pair of rollers 38. There is.

  In this case, while holding the elevating bracket 31, the elevating bracket 31 is rotated in the rotation direction R1 about the rotation shaft 58, thereby the length of the holder arm plate 59 (from the rotation shaft 58 to the elevating bracket 31). A moment of force having a moment arm as a length corresponding to the close contact portion acts on the rotation operation. Therefore, the lifting bracket 31 can be lifted smoothly against the biasing force of the spring 50 with a relatively weak force, and the pair of rollers 38 can be separated from the surface of the rail 4.

  FIG. 9 is a cross-sectional view corresponding to FIG. 6 of the present embodiment in the conventional position detecting device 127. Note that portions corresponding to the position detection device 27 of the present embodiment are denoted by the same reference numerals, and description thereof is omitted as appropriate.

  As shown in the figure, the elevating bracket 31 is attached to the fixed bracket 30 via a pair of front and rear rods 32 so as to be movable up and down. A bush 33 having a male screw formed on the outer periphery is fitted into the rod 32, and the bush 33 is screwed into the fixed bracket 30. The bush 33 is provided with a lock nut 34. A pair of springs 35 are fitted between the lifting bracket 31 and the bush 33 in the rod 32.

  Therefore, in the conventional position detecting device 127, when the pair of rollers 38 is separated from the surface of the rail 4, the vertically moving bracket 31 is maintained upward in the vertical direction against the two springs 35. Since it is necessary to lift the two springs 35, it is easy to pry the two springs 35, and it can be seen that it is considerably difficult to perform smoothly as compared with the position detection device 27 of the present embodiment.

  As described above, the position detection device 27 according to the present embodiment rotates the liftable bracket 31 about the rotation shaft 58 via the holder arm plate 59, whereby the rail 4 of the pair of rollers 38 in the position detection device 27. The lifting bracket 31 can be lifted away from the surface.

  In other words, the position detection device 27 according to the embodiment is centered on a rotation shaft 58 that is a predetermined rotation shaft by a rotation mechanism that mainly includes a bolt 57, a rotation shaft 58, a holder arm plate 59, and a rotation shaft support base 60. The pair of rollers 38 can be separated from the surface of the rail 4 by lifting the elevating bracket 31 that is a swinging bracket with a rotational movement having a moment arm depending on the arm length of the holder arm plate 59. It is.

  Accordingly, when the lifting bracket 31 is lifted by a rotating operation, the length of the holder arm plate 59 can be used as a moment arm, and therefore the lifting bracket 31 can be lifted smoothly without twisting the two springs 50. .

  As a result, the position detecting device 27 of the present embodiment reliably avoids the possibility of degrading the characteristics of the spring 50 such as the elastic force by the lifting operation of the elevating bracket 31, so that the durability is not affected. The high detection accuracy can be maintained.

  In addition, since the rail 4 is less likely to bend and deform as the portion is closer to the shelf 3, the roller 38 of the position detection device 27 is preferably brought into contact with the rail 4 as close to the shelf 3 as possible.

  The use of gears as interlocking means for rotating a plurality of rollers and interlocking shafts synchronously has an advantage that the structure is simple and that rotation can be accurately transmitted.

  Further, the roller is not limited to contact with the upper surface of the rail, but may be contacted with a side surface or an inner surface. Further, the interlocking shaft and the rotor of the rotary encoder may be integrated.

  The mobile carriage is not limited to the one shown in the figure, but generally refers to a vehicle that travels for loading and unloading, and thus includes a stacker crane and the like.

  In the present embodiment, the pair of springs 50 that are inclined obliquely upward are shown as the springs that apply the downward force to the liftable bracket 31. However, the elasticity of the springs such as providing the pair of springs vertically is shown. Of course, other modes may be used as long as the roller 38 can be brought into contact with the rail 4 in the normal state by the urging force due to the restoring force.

DESCRIPTION OF SYMBOLS 1 Hangar 2 Entry / exit part 4 Rail 5 Moving cart 27 Position detection apparatus 31 Elevating bracket 40, 42 Gear 41 Interlocking shaft 44 Rotary encoder 50 Spring 58 Rotating shaft 59 Shaft holder

Claims (1)

A traveling position detection device used for a mobile carriage in an automatic warehouse,
A plurality of rollers that are slidably contacted with the surface of the rail so as to rotate with the traveling of the movable carriage are provided, and the plurality of rollers are in contact with the same surface of the rail and are separated in the longitudinal direction of the rail. Are located in
An interlocking shaft that rotates in synchronization with the plurality of rollers via a gear group that is held in mesh with each other;
A rotary encoder that detects rotation of the interlocking shaft;
The movable carriage further includes a swing bracket that can rotate in a seesaw shape when viewed from a direction perpendicular to the rail and is biased downward by a spring, and sandwiches the center of rotation of the swing bracket. On both sides, the plurality of rollers are provided so as to contact the surface of the rail so as to roll freely,
A rotation mechanism capable of moving the plurality of rollers away from the rail by lifting the swinging bracket with a rotation operation along a first rotation direction around a predetermined rotation axis; rotation of the first rotation direction, to a second rotational direction which is the rotating direction applied to the rotation mechanism by the urging force of the spring is set in the opposite direction, along the first direction of rotation by the rotation mechanism The operation includes a moment arm between the predetermined rotating shaft and the swing bracket.
Traveling position detection device.

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