Loader carrier device

Abstract

To achieve good running stability easily.SOLUTION: A carrier device of a loader includes: a main frame 21; support rollers 31, 31 disposed at left and right upper parts of the main frame 21; and guide rollers 32, 33, 42, 43 which are disposed at left and right upper and lower parts of the main frame 21 while making pairs in an anteroposterior direction. Each pair of guide rollers 32, 33, 42, 43 biases one of the pair, a movable type guide roller, to the other of the pair, a fixed type guide roller, through springs 36, 46.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a loader carrier device that is useful, for example, when constructing an automatic workpiece processing line. [Background technology]

[0002] When constructing an automated processing line, it is known to combine a rack-driven self-propelled carrier with a rectangular cylindrical loader beam to form a loader capable of transporting heavy workpieces at high speed (for example, Patent Document 1).

[0003] That is, the loader beam is constructed by attaching rails to the top and bottom surfaces of a rectangular cylindrical beam, and the carrier has a pair of horizontally rotating guide rollers on the front and back of the carrier, which sandwich the corresponding rails to support the load in the front-to-back direction, and vertically rotating support rollers on the top left and right of the carrier roll on the top end surface of the upper rail to support the load in the vertical direction, thereby achieving the simplest combination. A robot arm with an appropriate end effector is attached to the front side of the carrier to perform various tasks such as loading, unloading, and transporting any workpiece as needed. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Microfilm of Japanese Utility Model Application No. 4-77490 (Japanese Utility Model Application No. 6-33638) Summary of the Invention [Problem to be solved by the invention]

[0005] In this prior art, since each pair of front and rear horizontally rotating guide rollers is fixedly disposed at a distance equivalent to the longitudinal width of the corresponding rail material, if there is an error in the parallelism or linearity of the upper and lower rail materials, there is a problem that an excessive torsional load is applied to the running carrier and the running resistance of the guide rollers increases. Furthermore, if the distance between the front and rear guide rollers is widened beyond the longitudinal width of the rail material, the contact state of each guide roller with the rail material will change, increasing the shaking of the carrier while it is running and potentially impairing the running stability of the carrier.

[0006] In view of the problems of the prior art, the object of the present invention is to provide a loader carrier device in which one of each pair of front and rear guide rollers is movable, thereby easily realizing good running stability without overly complicating the overall structure. [Means for solving the problem]

[0007] To achieve this object, the present invention is configured to include a main frame on which a traveling motor is mounted, support rollers located on the upper left and right sides of the main frame and which rotate vertically along the upper end surface of the upper rail material of the upper and lower rail materials of the loader beam, and guide rollers located on the upper and lower left and right sides of the main frame, one pair at the front and one at the back, which rotate horizontally, sandwiching the corresponding rail material of the loader beam between them, with one movable roller in each pair being biased by a spring toward the other fixed roller, and the gist of the configuration is that each pair of lower guide rollers is attached to the main frame as a roller unit that can be adjusted to move back and forth.

[0008] Each pair of guide rollers on the upper part of the main frame can be a combination of a small-diameter movable type on the front side of the upper rail material and a large-diameter fixed type on the rear side, and each pair of guide rollers on the lower part can be a combination of a large-diameter fixed type on the front side of the lower rail material and a small-diameter movable type on the rear side.

[0009] In addition, the movable guide roller may be attached to one end of a swinging bracket that swings back and forth, and the spring may be a compression spring that presses against the other end of the swinging bracket to cause it to swing, and the outer periphery of the movable guide roller that comes into contact with the rail material may be formed into an arc-shaped cross section.

[0010] Furthermore, the spring may not urge the movable guide roller when both of each pair of guide rollers are in contact with the rail material, but may urge the movable guide roller when the gap between them widens and the swing bracket swings, and each support roller and each pair of upper guide rollers may be mounted on the main frame as a common roller unit. [Effects of the Invention]

[0011] With this configuration, each pair of front and rear guide rollers rotates horizontally, sandwiching the corresponding rail material. Since one of the movable guide rollers is biased toward the other fixed guide roller via a spring, even if there is an error in the parallelism or linearity of the upper and lower rail materials, one of the movable guide rollers can follow the error and maintain contact with the rail material, thereby suppressing vibrations that occur in the carrier device while traveling and easily achieving good traveling stability. The carrier device is rack-driven by meshing a pinion at the end of the shaft of a traveling motor mounted on the main frame with a rack on the loader beam. The loader beam may be primarily made of, for example, a rectangular beam material, or may be made of a non-rectangular beam material, such as a cylindrical, channel-shaped, or I-shaped beam material.

[0012] The upper and lower guide rollers of the main frame are small-diameter movable rollers and large-diameter fixed rollers that are appropriately positioned in front of and behind the corresponding rail material.This allows the large-diameter fixed guide rollers to appropriately support the resulting horizontal load, even if the load applied to the main frame via a robot arm attached to the front side of the main frame is offset forward.

[0013] The movable guide roller is mounted on a swing bracket and is biased via a compression spring, so that the compression spring can be disposed on the fixed guide roller side, thereby making the overall structure compact.

[0014] Movable guide rollers, whose outer circumferences are formed in an arc-shaped cross section, are attached to oscillating brackets and always achieve constant surface contact with the rail material, even when the tilt angle of the shaft fluctuates, thereby preventing deformation of the guide rollers and wear of the rail material due to line contact.

[0015] The spring biases the movable guide roller only when the gap between each pair of guide rollers widens and the fixed guide roller moves away from the rail material, thereby minimizing the burden on the rail material and the increase in running resistance of the carrier device. Note that when biasing the movable guide roller, it is preferable that the spring pressure be equal to or greater than a preset value.

[0016] Each support roller and each pair of upper guide rollers are mounted on the main frame as a common roller unit, thereby making the entire unit compact and minimizing the number of assembly steps.

[0017] If each pair of lower guide rollers is mounted on the main frame as a roller unit that can be adjusted back and forth, the relative position of each pair of lower guide rollers to each pair of upper guide rollers can be more easily finely adjusted and set. [Brief explanation of the drawings]

[0018] [Figure 1] Overall configuration perspective view [Figure 2] Overall configuration diagram [Figure 3] Perspective view of the main components [Figure 4] Schematic cross-sectional view of line XX in Figure 3 [Figure 5] Enlarged view of the main part of Figure 4 [Figure 6] Main part configuration diagram [Figure 7]FIG. 10 is an enlarged view illustrating the configuration of a main part according to another embodiment of the present invention; DETAILED DESCRIPTION OF THE INVENTION

[0019] Hereinafter, an embodiment of the invention will be described with reference to the drawings.

[0020] The loader carrier device is combined with the loader beam 10 and comprises a main frame 21 on which a motor 22 is mounted, and roller units 30, 30, 40, 40 attached to the upper and lower left and right sides of the main frame 21 (Figs. 1 and 2). Figs. 2(A) to 2(C) are respectively a front view, a right side view, and a longitudinal cross-sectional view of the main part of Fig. 1. In the following description, the front, rear, left, and right directions correspond to the coordinate axis directions of Fig. 1.

[0021] The loader beam 10 is mainly composed of a rectangular cylindrical beam material 11. Strip-shaped rail materials 12 and 13 are fixed facing upward and downward to the upper and lower surfaces of the beam material 11. A traveling rack 14 is attached to the front side of the upper rail material 12 and faces forward.

[0022] The main frame 21 is a generally channel-shaped frame body, and is disposed facing rearward to house the loader beam 10 therein. A traveling motor 22 is mounted facing downward on the upper surface of the main frame 21, and a sprocket 23 on the shaft end of the motor 22 is engaged with a rack 14 on the loader beam 10. When the motor 22 is rotated forward and backward, the carrier device can be made to travel back and forth to the left and right.

[0023] One or two robot arms (not shown) can be attached to the front of the main frame 21. One robot arm can be provided, for example, on the central axis C1 of the front of the main frame 21, and two robot arms can be provided symmetrically side by side on the left and right of the central axis C1. In this case, the weight G of the robot arm and the workpiece grasped by the end effector at the tip of the robot arm is offset forward from the front of the main frame 21 and is loaded on the central axis C1.

[0024] The roller units 30, 30 on the upper part of the main frame 21 are each configured by integrally incorporating a support roller 31 and a pair of front and rear guide rollers 32, 33 into a frame member 34 (FIGS. 1 and 3). FIG. 3 is a rear perspective view of the roller unit 30 on the left side of FIG. 1. The roller units 30, 30 are disposed immediately above the rail material 12 on the loader beam 10 so as to protrude to the left and right of the main frame 21.

[0025] The base of the frame member 34 is fixed to the main frame 21 via a base plate 34a, and a sweep plate 34b that fits the rail material 12 is attached to the tip of the frame member 34. The support roller 31 is incorporated into the tip of the frame member 34 via a shaft 31a, and rotates vertically along the upper end surface of the upper rail material 12.

[0026] The guide rollers 32, 33 rotate horizontally, sandwiching the rail material 12 (FIGS. 3 and 4(A)). The front guide roller 32 is attached facing downward via a support pin 35a to one end of a swing bracket 35 that swings back and forth, while the rear guide roller 33 is attached facing downward to the rear of a frame member 34. The front guide roller 32 is a small-diameter movable type, while the rear guide roller 33 is a large-diameter fixed type. A spring 36 is set above the rear guide roller 33 via a bracket 36a and an adjustment bolt 36b. The head of the adjustment bolt 36b corresponds to the head of a set bolt 35b at the upper end (other end) of the swing bracket 35. The swing bracket 35 is incorporated into a mounting hole 34c of the frame member 34 via the support pin 35a, and the bracket 36a is screwed to the rear surface of the frame member 34 to stand upright.

[0027] Spring 36 is a compression spring made of a coil spring (FIGS. 4(A) and 5(A)), and is set horizontally on the upper end of bracket 36a via adjustment bolt 36b, together with sleeve 36c on bracket 36a and cap 36d on the head side. Adjustment bolt 36b passes through spring 36 and slidably penetrates sleeve 36c and cap 36d, and can adjust and set the spring pressure by expanding and contracting spring 36 via adjustment nut 36e and lock nut 36f that are screwed onto the threaded portion. In addition, a lock nut 35c is combined with set bolt 35b on the swing bracket 35 side.

[0028] By making the distance between the guide rollers 32, 33 equal to the width w of the corresponding rail material 12 in the front-to-rear direction, both can be properly grounded on the rail material 12 (FIG. 4(A)). At this time, the head of the adjustment bolt 36b on the spring 36 side abuts against the head of the set bolt 35b on the swing bracket 35, but the spring 36 does not apply spring pressure to the swing bracket 35 and does not bias the guide roller 32.

[0029] On the other hand, if the rail material 12 shifts forward relative to the rail material 12 while the carrier device is running due to its parallelism or linearity, and the gap between the guide rollers 32, 33 widens beyond the width w of the rail material 12 (FIG. 4(B)), the guide roller 32 is pushed forward, causing the swing bracket 35 to swing (in the direction of arrow K1 in the figure), compressing the spring 36 via the set bolt 35b and the adjustment bolt 36b, and the spring 36 can urge the guide roller 32 toward the guide roller 33 with a spring pressure equal to or greater than the set value (in the direction of arrow K2 in the figure). At this time, the guide roller 33 moves away from the rail material 12, and a gap d1 is formed between the guide roller 32 and the rail material 12.

[0030] Such an operating mode of the spring 36 can be achieved, for example, by the following adjustment procedure.

[0031] First, the spacing between the front and rear guide rollers 32, 33 is adjusted to the width w of the rail material 12, and both guide rollers 32, 33 are properly brought into contact with the rail material 12 (FIGS. 4(A) and 5(A)). In this state, the spring 36 is compressed via the adjustment nut 36e and adjustment bolt 36b (FIG. 5(B)). Once the spring pressure of the spring 36 is set to an appropriate value, it is set via the lock nut 36f. However, at this time, the set bolt 35b on the swing bracket 35 side is sufficiently retracted to ensure a gap d2 between the heads of the set bolt 35b and adjustment bolt 36b. Thereafter, the set bolt 35b is advanced until its head abuts against the head of the adjustment bolt 36b (FIG. 5(C)), and it is set via the lock nut 35c.

[0032] The roller units 40, 40 at the bottom of the main frame 21 are each configured by incorporating a pair of front and rear guide rollers 42, 43 integrally into a frame member 44 (FIGS. 2(A), (B), and 6). However, FIGS. 6(A) and (B) are respectively a bottom perspective view corresponding to FIG. 1 and an enlarged bottom view of a main part corresponding to the view of arrow Y in FIG. 6(A).

[0033] Each roller unit 40, 40 is disposed immediately below the rail material 13 below the loader beam 10, with the support roller 31 removed and the front-to-back direction reversed compared to roller unit 30. That is, the guide rollers 42, 43, frame member 44, swing bracket 45, and spring 46 in each roller unit 40, along with their associated components, correspond to the guide rollers 33, 32, frame member 34, swing bracket 35, spring 36, and their associated components in roller unit 30, and each roller unit 40 is assembled with a configuration similar to that of roller unit 30. Furthermore, the front and rear guide rollers 42, 43 of roller unit 40 are large-diameter fixed type and small-diameter movable type, respectively, and can operate in the same way as the guide rollers 33, 32 of roller unit 30. The frame member 44 of the roller unit 40 is attached to the main frame 21 via a base bracket 47 having front and rear adjustment screws 47a, 47a, and the roller unit 40 can be adjusted to move forward and backward via the adjustment screws 47a, 47a.

[0034] The spring pressure of the springs 46 of the roller units 40, 40 is adjusted to a set value in the same manner as the spring 36 of the roller unit 30, and the fixed positions in the front-to-rear direction relative to the main frame 21 are then adjusted via the adjustment screws 47a, 47a of the base bracket 47. That is, the adjustment screws 47a, 47a are set so that the front and rear guide rollers 42, 43 properly contact the rail 13 below the loader beam 10. Note that the position adjustment of each roller unit 40 is preferably performed at the point in the entire travel stroke of the carrier device where the lower rail 13 is most significantly displaced forward relative to the upper rail 12. This is because the rearward relative displacement of the rail 13 can be smoothly accommodated by the small-diameter movable guide roller 43 on the rear side.

[0035] Even if the weight G of the robot arm, workpiece, etc. is loaded in an offset manner forward of the main frame 21, the loader carrier device can support the vertical load via the support rollers 31, 31, and can also support the horizontal load via the upper and lower large-diameter fixed guide rollers 33, 33, 42, 42. Furthermore, errors in the parallelism and linearity of the upper and lower rail members 12, 13 of the loader beam 10 can be smoothly accommodated via the upper and lower small-diameter movable guide rollers 32, 32, 43, 43, and the carrier device can minimize shaking during travel, achieving good running stability, and the overall configuration is not overly complicated.

[0036] In the above description, the movable guide roller 32 attached to one end of the swing bracket 35 can have an outer periphery that comes into contact with the rail material 12 with an arc-shaped cross section (FIG. 7(A)). Regardless of the tilt angle of the axis of the guide roller 32 due to the swing of the swing bracket 35, the contact state of the guide roller 32 with the rail material 12 can be maintained as uniform surface contact (FIGS. 7(B) and (C)). The same applies to the movable guide roller 43 attached to one end of the swing bracket 45. [Industrial Applicability]

[0037] This invention can further improve the running stability of the carrier device and can be widely and suitably applied, for example, in automatic processing lines for precision machining that transport heavy workpieces at high speed, regardless of the length of the running stroke. [Explanation of symbols]

[0038] 10...Loader beam 12, 13...Rail material 21...Main frame 22...Motor 30, 40... Roller unit 31...Support roller 32, 33, 42, 43...Guide rollers 35, 45...Swing bracket 36, 46...Spring Patent applicant: Giken Co., Ltd.

Claims

1. A loader carrier device comprising: a main frame on which a traveling motor is mounted; support rollers arranged on the left and right upper parts of the main frame, which rotate vertically along the upper end surface of the upper rail material of the upper and lower rail materials of the loader beam; and guide rollers arranged on the front and rear upper and lower parts of the left and right upper parts of the main frame, respectively, which rotate horizontally, sandwiching the corresponding loader beam rail material therebetween, wherein one movable roller of each pair of guide rollers is biased toward the other fixed roller via a spring, and each lower pair of guide rollers is attached to the main frame as a roller unit which can be adjusted to move back and forth.

2. 2. The loader carrier device according to claim 1, wherein each pair of guide rollers on the upper part of the main frame is a combination of a small-diameter movable type on the front side of the upper rail material and a large-diameter fixed type on the rear side, and each pair of guide rollers on the lower part is a combination of a large-diameter fixed type on the front side of the lower rail material and a small-diameter movable type on the rear side.

3. 3. A loader carrier device according to claim 1, wherein the movable guide roller is attached to one end of a swing bracket that swings back and forth, and the spring is a compression spring that presses against the other end of the swing bracket to cause it to swing.

4. 4. The loader carrier device according to claim 3, wherein the movable guide roller has an outer periphery that contacts the rail material and has an arcuate cross section.

5. 5. A loader carrier device according to claim 3, wherein the spring does not bias the movable guide roller when both of the pair of guide rollers are in contact with the rail material, but biases the movable guide roller when the gap between the two rollers widens and the swing bracket swings.

6. 6. A carrier device for a loader according to claim 1, wherein each of said support rollers and each pair of said upper guide rollers are mounted on said main frame as a common roller unit.

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