Arm-type assistive device

Abstract

To provide an arm type assist device capable of reducing operation force when conveying a cargo handling object.SOLUTION: An arm type assist device 11 includes: a first arm 31 having a first support part 22 and a second support part 23; and a first rotation support part 21 for rotatably supporting the first support part 22 on a base 12. The arm type assist device 11 includes: a fixing support part 41 fixed to the second support part 23; and a bearing 44 fixed to the fixing support part 41. The arm type assist device 11 includes a second arm 51 supported by the fixing support part 41 by the bearing 44. The second arm 51 has a shaft 52 linearly movable in a horizontal direction by the bearing 44. The arm type assist device 11 includes: a second rotation support part 61 supported by a front end of the shaft 52 in the second arm 51; and an operation part 71 rotatably supported by the second rotation support part 61.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an arm-type assist device. [Background technology]

[0002] The arm-type assisting device is used in so-called palletizing, which is the transport of objects such as relatively heavy parts or loads from one fixed position to another fixed position. For example, Patent Document 1 discloses an object transporter as an example of the arm-type assisting device.

[0003] As shown in FIG. 14, the cargo handling machine 100 has a base 101, a swivel base 102, a main body 103, a first arm 104, a second arm 105, a bracket 106, a swivel base 107, an attachment 108, an operating lever 109, and a swivel base 110.

[0004] The swivel base 102 is provided on the upper surface of the base 101. The main body 103 is supported by the swivel base 102. The swivel base 102 allows the main body 103 to rotate. The first arm 104 is supported by the main body 103 so as to be swingable in the vertical direction. The bracket 106 is provided at the tip of the first arm 104. The swivel base 107 is provided at the lower end of the bracket 106. The second arm 105 is supported by the swivel base 107. The swivel base 107 allows the second arm 105 to rotate.

[0005] The attachment 108 is supported by a swivel base 110. The swivel base 110 enables the attachment 108 to rotate. An operating lever 109 is provided on the attachment 108. When an operator operates the operating lever 109, the operator can transport the cargo in three dimensions using the cargo transport machine 100. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 6681649 Summary of the Invention [Problem to be solved by the invention]

[0007] An arm-type assist device, such as the cargo transporter 100, is required to reduce the operating force required to transport cargo. [Means for solving the problem]

[0008] The arm-type assist device for solving the above problems comprises a base, a first arm having a first support part at a first end in the axial direction and a second support part at a second end in the axial direction that is swingable up and down parallel to the first support part by a parallelogram link, the first arm having an assist mechanism using an actuator built in, a first rotating support part having a first vertical axis as a center of rotation and rotatably supporting the first support part on the base, a fixed support part fixed to the second support part and having a horizontal upper surface, a bearing fixed to the upper surface of the fixed support part, a second arm supported on the fixed support part by the bearing, the second arm having a shaft that can move linearly in the horizontal direction by the bearing, a second rotating support part supported by a front end of the shaft on the second arm and having a second vertical axis as a center of rotation, and an operating part rotatably supported by the second rotating support part.

[0009] In an arm-type assistive device, the bearings may be arranged in parallel in the direction of gravity, the second arm may have a plurality of the shafts, each of the plurality of shafts may be supported by the fixed support portion by the bearing, and the plurality of shafts may be arranged in parallel in the direction of gravity.

[0010] In the arm-type assistive device, each of the first rotation support portion, the second rotation support portion and the second arm may include a brake mechanism. In an arm-type assistive device, the brake mechanism provided on the second arm may have a brake shaft and a shaft braking part, the brake shaft extending horizontally parallel to the shaft and supported by the shaft braking part, and the brake shaft may be capable of linear movement in the horizontal direction integral with the shaft.

[0011] In an arm-type assistive device, the second arm may have a plurality of the shafts, the plurality of shafts being arranged in parallel in the direction of gravity, and the shaft braking unit may be disposed between the shafts arranged in parallel in the direction of gravity.

[0012] In an arm-type assistive device, the second arm may have an axis insertion member at its front end, and a swing hole extending longitudinally in the direction of gravity may be formed in the axis insertion member, and the front end of the brake shaft may be inserted into the swing hole.

[0013] In the arm-type assist device, the braking shaft may have a smaller diameter than the shaft. In an arm-type assistive device, the second arm has a swing support part provided at the front end of the shaft, and a swing member supported so as to be swingable in the front-to-rear direction relative to the swing support part, the second rotation support part is supported by the swing member, and the arm-type assistive device may have a swing regulating part that regulates the swing angle of the swing member in the front-to-rear direction.

[0014] In the arm-type assistive device, the bearing may be capable of adjusting a fixed position along the upper surface of the fixed support part. Effect of the Invention

[0015] The present invention can reduce the operating force required to transport cargo. [Brief description of the drawings]

[0016] [Figure 1] FIG. 2 is a side view showing an arm-type assist device. [Diagram 2] FIG. 1 is a perspective view showing an example of use of an arm-type assistance device. [Diagram 3] FIG. 4 is an exploded perspective view showing components of the first arm. [Figure 4] FIG. 2 is a schematic diagram showing a parallelogram link. [Diagram 5] FIG. 2 is a schematic diagram showing a parallelogram link. [Figure 6] FIG. 4 is a perspective view showing the periphery of a second arm. [Figure 7] FIG. 4 is a perspective view showing the periphery of a second arm. [Figure 8] FIG. 4 is a perspective view showing the periphery of a swing restriction portion. [Figure 9] FIG. 4 is a side view showing the periphery of the swing restriction portion. [Figure 10] FIG. 11 is a diagram for explaining an operating force in a comparative example. [Figure 11] 4A and 4B are diagrams for explaining an operating force of the arm-type assist device according to the embodiment. [Figure 12] FIG. 11 is a partial perspective view showing another example of an arm-type assisting device. [Figure 13] FIG. 11 is a partial side view showing another example of an arm-type assisting device. [Figure 14] FIG. 1 is a perspective view showing the background art. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, one embodiment of an arm-type assist device will be described with reference to Figs. <Overall arm-type assistive device> 1, the arm-type assistive device 11 has a base 12, a first rotation support part 21 supported by the base 12, and a first arm 31 supported by the first rotation support part 21. The arm-type assistive device 11 also has a fixed support part 41 supported by the first arm 31, a second arm 51 supported by the fixed support part 41, and a second rotation support part 61 supported by the second arm 51. In addition, the arm-type assistive device 11 has an operation part 71 supported by the second rotation support part 61. The arm-type assistive device 11 has an air supply source 14 and a control device 15.

[0018] <Air supply source and control device> The air supply source 14 supplies compressed air to the arm type assistance device 11. In the following description, compressed air will be simply referred to as "air". The control device 15 controls pneumatic equipment (not shown) and adjusts the air pressure. The control device 15 calculates the air pressure to be supplied to the arm type assistance device 11 in order to balance the weight of the load suspended by the arm type assistance device 11.

[0019] <Base> The base 12 is columnar. The base 12 does not have to be a column. For example, the base 12 may be a low platform. The shape of the base 12 is arbitrary.

[0020] <First rotation support part> The first rotation support part 21 is fixed to the upper end of the base 12. The first rotation support part 21 rotatably supports the first arm 31. The first rotation support part 21 has a first brake mechanism 161 that regulates the rotation of the first rotation support part 21. The first rotation support part 21 rotates about a first vertical axis Z1.

[0021] <First brake mechanism> The first brake mechanism 161 has a rotation lock disc 161a and a locking device (not shown). The rotation lock disc 161a rotates integrally with the first arm 31. The locking device of the first brake mechanism 161 moves away from the rotation lock disc 161a when air of a predetermined pressure or higher is supplied. This causes the first brake mechanism 161 to enter a non-braking state. The non-braking state of the first brake mechanism 161 allows the first arm 31 to rotate by the first rotation support portion 21.

[0022] When the pressure is less than a predetermined pressure, the locking device of the first brake mechanism 161 is biased toward the rotation lock disk 161a by a biasing member (not shown). The locking device then clamps the rotation lock disk 161a. This places the first brake mechanism 161 in a braking state. The braking state of the first brake mechanism 161 prohibits the rotation of the first arm 31 by the first rotation support portion 21.

[0023] <First Arm> 3 and 4, the first arm 31 has a hollow arm body 32, a first pivotal support member 33 connected to a first axial end of the arm body 32, a second pivotal support member 34 connected to a second axial end of the arm body 32, and a second member 46. The first arm 31 also has a first support part 22 connected to the first pivotal support member 33, and a second support part 23 connected to the second pivotal support member 34. Furthermore, the first arm 31 has a built-in driving air cylinder 91 as an assisting mechanism.

[0024] <Arm body> The arm body 32 has a cylinder tube 91 a of a driving air cylinder 91 , two first cover members 95 , and one second cover member 96 .

[0025] The main body of the arm body 32 is a cylinder tube 91a of the driving air cylinder 91. Two first cover members 95 are fixed to the outer surface of the cylinder tube 91a. The two first cover members 95 face each other in the radial direction of the cylinder tube 91a. A second cover member 96 is fixed between the upper ends of the two first cover members 95.

[0026] <First support member and second support member> The first pivotal support member 33 is fixed to a first end of the cylinder tube 91a. The second pivotal support member 34 is fixed to a second end of the cylinder tube 91a. Therefore, the first arm 31 has a first end portion 35 formed by the first pivotal support member 33 at a first axial end. The first arm 31 also has a second end portion 36 formed by the second pivotal support member 34 at a second axial end. The arm body 32, the first pivotal support member 33, and the second pivotal support member 34 constitute a first member 45.

[0027] <First Support Part and Second Support Part> As shown in Figs. 1 and 2, the first support part 22 is supported by the first rotation support part 21. The first support part 22 is rotatable by the first rotation support part 21. The first support part 22 rotates about a first vertical axis Z1 along the axis of the base 12. In other words, the first rotation support part 21 supports the first support part 22 rotatably on the base 12 around the first vertical axis Z1. The rotation range of the first rotation support part 21 and the first support part 22 is less than 360 degrees. In this embodiment, the rotation range of the first support part 22 is 300 degrees.

[0028] 3, the first support portion 22 has a disk-shaped base plate 22a and a pair of first pivotal support portions 22b standing upward from the base plate 22a. The pair of first pivotal support portions 22b face each other with a gap therebetween.

[0029] The second support portion 23, which is paired with the first support portion 22, has a disk-shaped support plate 23a and a plate-shaped second shaft support portion 23b standing downward from the support plate 23a. A plurality of female threads 23c are formed on the support plate 23a.

[0030] The first end 35 is disposed between the pair of first pivotal supports 22b of the first support portion 22. A first horizontal axis H1 is inserted through the first pivotal support portion 22b and the first pivotal support member 33. Therefore, the first arm 31 has the first support portion 22 at the first end 35 in the axial direction. The arm body 32 is supported so as to be able to swing up and down relative to the first support portion 22 around the first horizontal axis H1 as the swing center. Therefore, the first arm 31 can swing up and down.

[0031] The second end 36 is disposed on the second pivotal support portion 23b of the second support portion 23. The second horizontal axis H2 is inserted through the second pivotal support portion 23b. Therefore, the first arm 31 has the second support portion 23 at the second end 36 in the axial direction. The arm body 32 is supported so as to be swingable in the up-down direction relative to the second support portion 23 about the second horizontal axis H2 as the swing center.

[0032] <Second member> The second member 46 is disposed between the lower ends of the two first cover members 95. The second member 46 has a rectangular bar shape. As shown in Fig. 4, a first end 47 of the second member 46 is supported by the first support portion 22 via a third horizontal shaft H3 so as to be swingable in the vertical direction. A second end 48 of the second member 46 is supported by the second support portion 23 via a fourth horizontal shaft H4 so as to be swingable in the vertical direction.

[0033] <Actuator> 4 and 5, the actuator 90 has an operating rod 92 of a driving air cylinder 91, a link member 93, and a connecting body 94. The operating rod 92 moves in the axial direction of the first arm 31. A first end of the link member 93 is swingably supported by the first support portion 22 by a third horizontal axis H3. The link member 93 is inclined with respect to the operating rod 92. The connecting body 94 is connected to second ends of the operating rod 92 and the link member 93.

[0034] A piston 91b is movably housed in a cylinder tube 91a of the driving air cylinder 91. An operating rod 92 is connected to the piston 91b. The piston 91b moves in the axial direction of the first arm 31 in association with the movement of the operating rod 92.

[0035] <Parallelogram link> The parallelogram link is composed of a first member 45, a first support portion 22, a second support portion 23, and a second member 46. When the first member 45 and the second member 46 swing vertically relative to the first support portion 22 with the movement of the operating rod 92 of the driving air cylinder 91, the second support portion 23 moves parallel to the vertical direction.

[0036] At this time, the upper surface of the second support part 23 is maintained horizontal. The first member 45 and the second member 46 form the long sides of a parallelogram, and the first support part 22 and the second support part 23 form the short sides of the parallelogram. Therefore, the first arm 31 has the first support part 22 at the first end part 35, and has the second support part 23 at the second end part 36, which can swing up and down parallel to the first support part 22 by the parallelogram link.

[0037] <Fixed support part> 1 and 3, the fixed support part 41 is fixed to the support plate 23a of the second support part 23. The fixed support part 41 has a fixed base 42 and two bearings 44.

[0038] As shown in FIG. 3, the fixed base 42 is plate-shaped. The fixed base 42 has a horizontal upper surface 42b and a plurality of through holes 42a. Each of the plurality of through holes 42a opens on the upper surface 42b. The plurality of through holes 42a are arranged in a ring shape at equal intervals. A bolt (not shown) can be inserted into the through hole 42a. The bolt inserted into the through hole 42a is screwed into the female thread 23c of the second support portion 23. The fixed base 42 is fixed to the upper surface of the second support portion 23 by this screwing.

[0039] <Bearings> As shown in FIG. 6 and FIG. 7, the two bearings 44 are fixed to the upper surface 42b of the fixed base 42 in the fixed support part 41. The two bearings 44 are so-called linear bushes. Each of the two bearings 44 has a rectangular parallelepiped body 44a and a ball (not shown) built into the body 44a. The two bearings 44 are arranged side by side in the direction of gravity. Of the two bearings 44, the lower bearing 44 is fixed to the upper surface 42b of the fixed base 42. The other bearing 44 is fixed to the upper surface of the bearing 44 fixed to the fixed base 42. The central axis of the body 44a extends horizontally. The central axes of the two bodies 44a are parallel to each other. In addition, both end surfaces of the two bearings 44 in the axial direction are flush with each other.

[0040] <Second Arm> The second arm 51 has two shafts 52, a first shaft connecting member 53, and a second shaft connecting member 54. The second arm 51 may also have a second brake mechanism 162, a swing support part 56, a swing member 59, and a swing restriction part 80.

[0041] <Shaft> The two shafts 52 are round shafts of the same diameter. The two shafts 52 are arranged side by side in the direction of gravity. Of the two shafts 52, the lower shaft 52 is supported on the fixed base 42 by the lower bearing 44 of the two bearings 44. The other shaft 52 is supported on the fixed base 42 by the upper bearing 44. As a result, the second arm 51 is supported on the fixed support part 41 by the bearing 44. In a top view of the arm-type assist device 11 looking in the direction of gravity, the first arm 31 and the second arm 51 are arranged in a straight line.

[0042] The central axes of the two shafts 52 extend horizontally. The central axes of the two shafts 52 are parallel to each other. The two shafts 52 are arranged parallel to each other in the direction of gravity by the bearings 44. The two shafts 52 are supported so as to be linearly movable in the horizontal direction. Therefore, the second arm 51 is supported by the fixed support part 41 and is linearly movable in the horizontal direction by the bearings 44.

[0043] As shown in Fig. 5, the horizontal length of the first arm 31 in the axial direction is defined as "L1". The length of the second arm 51 in the axial direction is defined as "L2". The protruding length of the second arm 51 from the bearing 44 is defined as "L3". The length of the bearing 44 in the axial direction of the second arm 51 is defined as "L4". In addition, the load when an object is held at the tip of the arm-type assistance device 11 by the object holding portion 79 described later is defined as "W".

[0044] In this case, a moment of the following formula 1 acts on bearing 44 supporting second arm 51. Moment = L3 x W…Equation 1 The moment acting on the bearing 44 increases as the protruding length "L3" of the second arm 51 from the bearing 44 increases. Also, the longer the protruding length "L3" of the second arm 51 from the bearing 44, the greater the amount of deflection of the second arm 51.

[0045] Further, the bearing 44 is subjected to a force expressed by the following formula 2. Force=W×L3 / L4…Equation 2 Since the length "L4" of the bearing 44 is constant, the force acting on the bearing 44 increases as the protruding length "L3" of the second arm 51 from the bearing 44 increases. The amount of deflection of the second arm 51 decreases as the second moment of area of ​​the axis of the second arm 51 increases. The second arm 51 has two shafts 52 of the same diameter. When two shafts 52 of the same diameter are arranged in the horizontal direction, the second moment of area is twice as large as when there is only one shaft 52 of the same diameter. When two shafts 52 of the same diameter are arranged in the direction of gravity, the second moment of area is more than twice as large and increases as the distance between the two shafts 52 increases. Therefore, the amount of deflection of the second arm 51 decreases as compared to when there is only one shaft 52.

[0046] <First shaft connecting member and second shaft connecting member> 6 and 7, the first shaft connecting member 53 connects the rear ends of the two shafts 52. The second shaft connecting member 54 connects the front ends of the two shafts 52. The first shaft connecting member 53 and the second shaft connecting member 54 maintain the two shafts 52 in parallel.

[0047] The second shaft connecting member 54 has a shaft insertion member 55 fixed to its upper end surface. It can be said that the second arm 51 has the shaft insertion member 55. The shaft insertion member 55 is L-shaped and has two orthogonal plate portions. One of the two plate portions of the shaft insertion member 55 is fixed to the upper end surface of the second shaft connecting member 54. The other of the two plate portions of the shaft insertion member 55 extends upward from the upper end surface of the second shaft connecting member 54. A swing hole 55a is formed in the other of the two plate portions of the shaft insertion member 55. The swing hole 55a is an elongated hole that extends longitudinally in the direction of gravity.

[0048] <Second brake mechanism> The second brake mechanism 162 is capable of restricting the linear movement of the second arm 51 . The second brake mechanism 162 has a brake shaft 162a and a shaft braking portion 162b. The second brake mechanism 162 may have a pair of shaft supports 162c. The pair of shaft supports 162c are attached to the body 44a of the bearing 44 located on the upper side in the direction of gravity of the two bearings 44. The pair of shaft supports 162c are attached to both ends of the body 44a in the axial direction. The shaft braking portion 162b is attached to the upper surface of the body 44a of the bearing 44 located on the upper side in the direction of gravity of the two bearings 44. In other words, the shaft braking portion 162b is arranged in parallel with the bearing 44 in the direction of gravity.

[0049] The braking shaft 162a extends in the horizontal direction parallel to the shaft 52, and is supported by a shaft braking portion 162b and a pair of shaft supports 162c. The braking shaft 162a is capable of linear movement integrally with the shaft 52 in the horizontal direction.

[0050] The rear end of the brake shaft 162a is a free end. The front end of the brake shaft 162a is inserted into the swing hole 55a. The brake shaft 162a is flexible in the longitudinal direction of the swing hole 55a. The brake shaft 162a is a round bar having a smaller diameter than the shaft 52.

[0051] The braking shaft 162a passes through the shaft braking portion 162b. The shaft braking portion 162b incorporates a piston, a clamper, and a biasing spring, none of which are shown. The clamper is cylindrical and surrounds the braking shaft 162a. The piston expands or contracts the diameter of the clamper. The biasing spring biases the piston in a direction away from the clamper.

[0052] When air of a predetermined pressure or more is supplied to the shaft braking portion 162b, the piston moves toward the clamper against the biasing force of the biasing spring. Then, the clamper expands in diameter and moves away from the braking shaft 162a. As a result, the second brake mechanism 162 is in a non-braking state. The non-braking state of the second brake mechanism 162 allows the linear movement of the braking shaft 162a. Therefore, the linear movement of the second arm 51 is allowed.

[0053] On the other hand, when the shaft braking portion 162b is less than the predetermined pressure, the piston is moved in a direction away from the clamper by the biasing spring. Then, the clamper contracts in diameter to clamp the braking shaft 162a. As a result, the second brake mechanism 162 is in a braking state. The braking state of the second brake mechanism 162 prohibits the linear movement of the braking shaft 162a. Therefore, the linear movement of the second arm 51 is prohibited.

[0054] <Swing support part> 8 and 9, the swing support part 56 is provided at the front end of the second shaft connecting member 54. Therefore, the swing support part 56 is provided at the front end of the second arm 51. The swing support part 56 has a shaft support member 57 and a swing shaft 58.

[0055] The pivot member 57 is in the shape of a square plate. The pivot member 57 protrudes forward from the front end of the second shaft connecting member 54. The oscillating shaft 58 penetrates the pivot member 57 in the plate thickness direction. The axis of the oscillating shaft 58 extends horizontally. The oscillating shaft 58 is rotatably supported by the pivot member 57. A first end of the oscillating shaft 58 protrudes from one surface of the pivot member 57 in the plate thickness direction. A second end of the oscillating shaft 58 protrudes from the other surface of the pivot member 57 in the plate thickness direction.

[0056] Each of the two swing members 59 has a connecting portion 59a and a branching portion 59b. The connecting portion 59a is a rectangular plate-shaped portion. The branching portion 59b is a portion below the connecting portion 59a. The branching portion 59b branches into two from the lower end of the connecting portion 59a.

[0057] The connecting portion 59a of one of the swing members 59 is fixed to a first end of the swing shaft 58. The connecting portion 59a of the other swing member 59 is fixed to a second end of the swing shaft 58. The two swing members 59 swing integrally with the swing shaft 58. Therefore, the second arm 51 has the swing member 59 supported by the swing support portion 56 so as to be swingable in the front-rear direction.

[0058] A connecting plate 60 is fixed to the swinging members 59. The connecting plate 60 is fixed to the lower end surfaces of the branched portions 59b of the two swinging members 59. Therefore, the connecting plate 60 can swing integrally with the swinging members 59 in the front-rear direction.

[0059] <Swing control part> The swing restriction portion 80 has two brackets 81 and two restriction protrusions 82. The two brackets 81 are fixed to one surface in the plate thickness direction of the pivot support member 57. The two brackets 81 are disposed at positions sandwiching the connecting portion 59a.

[0060] Bracket 81 is L-shaped and has two orthogonal plate portions. One of the two plate portions of bracket 81 is fixed to pivot member 57. The other of the two plate portions of bracket 81 is an extension piece 81a that is orthogonal to pivot member 57.

[0061] One restricting protrusion 82 is attached to one extension piece 81a, and the other restricting protrusion 82 is attached to the other extension piece 81a. Each of the two restricting protrusions 82 has a restricting bolt 83 and a nut 84 screwed onto the restricting bolt 83. The restricting bolt 83 is fastened to the extension piece 81a by the nut 84 with the head facing the branching portion 59b. By adjusting the amount of screwing of the restricting bolt 83 into the nut 84, the amount of protrusion of the restricting bolt 83 from the extension piece 81a toward the branching portion 59b can be adjusted.

[0062] A small gap is formed between the head of the regulating bolt 83 along the direction of gravity and the branch portion 59b. This small gap allows the swinging member 59 to swing in the front-rear direction. By adjusting the amount of protrusion of the regulating bolt 83 and the size of the gap between the head of the regulating bolt 83 and the branch portion 59b, the swing angle of the swinging member 59 in the front-rear direction can be regulated. Therefore, the arm-type assistive device 11 has a swing regulating portion 80 that regulates the swing angle of the swinging member 59.

[0063] <Second rotation support part> The second rotation support part 61 is fixed to the lower surface of the connecting plate 60. As described above, the connecting plate 60 is fixed to the swinging member 59. The swinging member 59 is supported by the swinging support part 56. The swinging support part 56 is connected to the front end of the shaft 52 via the second shaft connecting member 54. Therefore, it can be said that the second rotation support part 61 is supported by the front end of the shaft 52 of the second arm 51.

[0064] The connecting plate 60 is fixed to the lower end surface of the swinging member 59. Therefore, the second rotation support part 61 is supported by the two swinging members 59 via the connecting plate 60. As described above, the connecting plate 60 can swing in the front-rear direction integrally with the swinging members 59. Therefore, the second rotation support part 61 fixed to the connecting plate 60 can swing in the front-rear direction integrally with the swinging members 59.

[0065] As shown in Fig. 1, an operating unit 71 is supported below the second rotation support part 61. The second rotation support part 61 rotates about a second vertical axis Z2 below the connecting plate 60. The second rotation support part 61 has the same structure as the first rotation support part 21. The rotation range of the second rotation support part 61 is less than 360 degrees. In this embodiment, the rotation range of the second rotation support part 61 is 300 degrees.

[0066] The second rotation support portion 61 has a third brake mechanism 163. The third brake mechanism 163 has the same configuration as the first brake mechanism 161, and therefore has a rotation lock disk 161a and a lock device (not shown) like the first brake mechanism 161. The function of the third brake mechanism 163 is the same as that of the first brake mechanism 161, and therefore a detailed description thereof will be omitted.

[0067] The locking device of the third brake mechanism 163 is separated from the rotation lock disk 161a by the supply of air of a predetermined pressure or more. Then, the third brake mechanism 163 is in a non-braking state. The non-braking state of the third brake mechanism 163 allows the second rotation support portion 61 to rotate the operating portion 71.

[0068] When the pressure is less than a predetermined pressure, the locking device of the third brake mechanism 163 is biased toward the rotation lock disk 161a by a biasing member (not shown). The locking device then clamps the rotation lock disk 161a. This causes the third brake mechanism 163 to enter a braking state. The braking state of the third brake mechanism 163 prohibits the second rotation support portion 61 from rotating the operating portion 71.

[0069] <Operation section> The operating unit 71 is supported below the second rotation support part 61. The second rotation support part 61 is rotatable around the second vertical axis Z2. Since the operating unit 71 is integrated with this second rotation support part 61, the operating unit 71 is rotatable around the second vertical axis Z2. In addition, the load holding part 79 is integrated with the operating unit 71. Therefore, the load holding part 79 is also rotatable around the second vertical axis Z2.

[0070] A load sensor 72 is built into the operation unit 71. The load sensor 72 detects a load W including a load suspended and held by the load holding unit 79. The load sensor 72 outputs a signal related to the detected value to the control device 15 of the arm-type assistance device 11. A detection switch 73 is built into the operation unit 71. The detection switch 73 is signal-connected to the control device 15. When the detection switch 73 detects that the operation unit 71 is being operated, it is turned on and outputs an on signal to the control device 15.

[0071] The operation unit 71 is provided with a pair of operation handles 74. When the operator is in an operating state where the operation handles 74 are gripped by the operator, the detection switch 73 detects that the operation unit 71 is being operated and is turned on. On the other hand, in a non-operating state where the operator is not gripping the operation handles 74, the detection switch 73 is turned off.

[0072] <Cableveyor (registered trademark)> As shown in Figs. 6 and 7, the arm-type assist device 11 may have a cable bear 78. The cable bear 78 has two rectangular tubular cases 78a and a flexible part 78b. The two cases 78a are arranged laterally of the two bearings 44. A first end of one case 78a is connected to the upper end of the second shaft connecting member 54 by a first bracket 78c. A second end of one case 78a is connected to the first end of the flexible part 78b. A second end of the flexible part 78b is connected to the first end of the other case 78a. A second end of the other case 78a is fixed to the fixed base 42 by a second bracket 78d. Various wiring and air piping are housed inside the cable bear 78. The various wiring connects the control device 15 to the load sensor 72 and the detection switch 73. The air piping connects the air supply source 14 to the driving air cylinder 91, the first brake mechanism 161, and the third brake mechanism 163.

[0073] <Operation of arm-type assistive device> In the arm-type assistive device 11, when a power source (not shown) is turned on, the detection value of the load sensor 72 is input to the control device 15. The control device 15 calculates a balance pressure for balancing the driving air cylinder 91 of the first arm 31 and starts pressure control.

[0074] When the worker grasps the operating handle 74 and the operating unit 71 is in an operating state, the detection switch 73 is turned on. The control device 15 receives an ON signal from the detection switch 73. When the control device 15 receives an ON signal from the detection switch 73, it causes the air supply source 14 to supply operating air. A balance pressure is supplied to the driving air cylinder 91. The driving air cylinder 91 is in a balanced state. At the same time, operating air is also supplied to the first to third brake mechanisms 161 to 163. Then, the first to third brake mechanisms 161 to 163 are released from their braked states and are simultaneously put into a non-braked state. As a result, the arm-type assist device 11 becomes capable of vertical movement, linear movement and rotation, and also becomes capable of transporting cargo.

[0075] The volume of the piston chamber of the drive air cylinder 91 changes as the operating unit 71 moves up and down. The control device 15 calculates the balance pressure based on the detection value of the load sensor 72. The control device 15 supplies the balance pressure to the drive air cylinder 91 so that the force passing through the parallelogram link of the first arm 31 is balanced. This controls the balance pressure of the arm-type assistive device 11. By maintaining the balanced state, the worker can operate the operating unit 71 with a small operating force.

[0076] When the operating unit 71 is not being operated, the control device 15 always maintains control to balance the load. The control device 15 prevents air from flowing into or out of the driving air cylinder 91. This suppresses the up and down movement of the arm-type assistive device 11. In other words, the driving air cylinder 91 is in a state beyond the reach of pressure control. In this state, the pressure of the driving air cylinder 91 acts as a force against the operation of the operating unit 71, so the position of the operating unit 71 is maintained.

[0077] <Function of the arm-type assistive device> FIG. 10 is a schematic top view of an arm-type assistive device 200 of a comparative example. The arm-type assisting device 200 of the comparative example has a first rotation support part 21, a first arm 31, a second arm 51, a second rotation support part 201, and an operation part 71. In the arm-type assisting device 200 of the comparative example, the second rotation support part 201 rotatably supports the second arm 51, unlike the second rotation support part 61 of the embodiment. The second arm 51 rotates about the second vertical axis Z2. Therefore, the arm-type assisting device 200 of the comparative example has one more rotatable part than the arm-type assisting device 11 of the embodiment.

[0078] When the operating unit 71 of the arm-type assistive device 200 of the comparative example is operated with an operating force F, the angle formed between the direction of the operating force F and the axial direction of the first arm 31 is defined as "α". The angle formed between the direction of the operating force F and the axial direction of the second arm 51 is defined as "β". As described above, the horizontal length of the first arm 31 in the axial direction is defined as "L1". The length of the second arm 51 in the axial direction is defined as "L2".

[0079] The operation torque required to rotate the first arm 31 about the first vertical axis Z1 is defined as "T1". The operation torque T1 is expressed by the following formula 3. T1=L1×F×cosβ×sin(α+β)…Equation 3 The operation torque T1 when the operation unit 71 is operated with an operation force F is "0" when the angle "β" is 90° or 270°, and when the angle "α+β" is 0° or 180°.

[0080] The operation torque required to rotate the second arm 51 about the second vertical axis Z2 is defined as "T2." The operation torque T2 is expressed by the following equation 4. T2=L2×F×sinβ…Equation 4 The operation torque T2 when the operation portion 71 is operated with an operation force F becomes "0" when the angle "β" is 0° or 180°.

[0081] When the operating torques T1, T2 become "0", it means that the posture of the arm-type assistive device 200 cannot be controlled even if the operating unit 71 is operated with the operating force F. The arm-type assistive device 200 of the comparative example has a plurality of postures that cannot be controlled. For this reason, when moving an object in a straight line using the arm-type assistive device 200, if the operating force F is aligned with the direction of movement, the arm-type assistive device 200 will be located at a position where it cannot operate. Therefore, there are a plurality of positions where the arm-type assistive device 200 of the comparative example cannot operate.

[0082] FIG. 11 shows a schematic diagram of an arm-type assistive device 11 according to an embodiment of the present invention. When the operating unit 71 of the arm-type assistive device 11 of the embodiment is operated with an operating force F, the angle formed between the direction of the operating force F and the axial direction of the first arm 31 is defined as "α". The angle formed between the direction of the operating force F and the axial direction of the second arm 51 is defined as "β". Since the second arm 51 does not rotate with respect to the first arm 31, the angle "β" is equal to the angle "α". As described above, the horizontal length of the first arm 31 in the axial direction is defined as "L1". The length of the second arm 51 in the axial direction is defined as "L2". In addition, the protruding length of the second arm 51 from the first arm 31 is defined as "L3".

[0083] The operation torque required to rotate the second arm 51 together with the first arm 31 about the first vertical axis Z1 as the center of rotation is defined as "T12". The operation torque "T12" is expressed by the following equation 5.

[0084] T12=(L1+L3)×F×sinβ…Equation 5 The operation torque T12 when the operation unit 71 is operated with an operating force F becomes "0" when the angle "β" is 0° or 180°. When the operation torque T12 becomes "0", the posture of the arm-type assistance device 11 cannot be controlled even if the operation unit 71 is operated with the operating force F. In the embodiment, the arm-type assistance device 11 has only one posture that cannot be controlled. For this reason, when moving an object in a straight line using the arm-type assistance device 11, if the operating force F is aligned with the direction of movement, the arm-type assistance device 11 cannot operate, but there is only one position for this.

[0085] Furthermore, in the arm-type assistive device 11, the first arm 31 and the second arm 51 are integrated in a straight line, so the overall arm length "L1+L3" is longer than that of the arm-type assistive device 200 of the comparative example. For this reason, the operation torque T12 is greater than the operation torques T1 and T2. Therefore, the arm-type assistive device 11 can reduce the operation force F compared to the arm-type assistive device 200 of the comparative example.

[0086] <Effects of the embodiment> According to the above embodiment, the following effects can be obtained. (1) The first arm 31 is rotatably supported on the base 12 by the first rotation support part 21. The operating part 71 is rotatably supported on the second arm 51 by the second rotation support part 61. The second arm 51 is supported by the fixed support part 41 so as not to rotate relative to the first arm 31. When a worker operates the operating part 71 of the arm-type assisting device 11, the arm-type assisting device 11 requires an operating torque for rotating the first arm 31 and the second arm 51 together around the first rotation support part 21, and an operating torque for rotating the operating part 71. On the other hand, the arm-type assisting device 11 does not require an operating torque for rotating between the first arm 31 and the second arm 51.

[0087] A comparative example is a case where rotation is also possible between the first arm 31 and the second arm 51. Compared to the comparative example, the arm-type assist device 11 requires less operating force because the operating torque acts effectively on the rotation around the first rotation support part 21. As a result, the operating force required when transporting cargo can be reduced.

[0088] In the arm-type assisting device 11, the second arm 51 is fixed to the first arm 31. Therefore, the arm-type assisting device 11 can transport an object without rotating the second arm 51 relative to the first arm 31. In other words, the operating force of the operating unit 71 is directly transmitted to the first arm 31 without rotating the second arm 51.

[0089] For example, the operating force of the operating unit 71 is more easily transmitted to the first arm 31 than when the second arm 51 and the first arm 31 also rotate. The larger the angle at which the second arm 51 rotates relative to the first arm 31, the less the operating force is transmitted to the second arm 51, so the operating force can be reduced when the second arm 51 does not rotate. As a result, the worker can operate the first arm 31 appropriately and with less operating force by operating the operating unit 71. Therefore, the arm-type assist device 11 can reduce the amount of rotation required to operate the operating unit 71, thereby reducing the operating force required to transport the load.

[0090] In particular, when it is desired to transport an object in a straight line over a short distance from one point to another, the absence of rotation of the second arm 51 makes the transport easier and shortens the transport time. Furthermore, since the second arm 51 does not rotate with respect to the first arm 31, no bent portion is formed between the first arm 31 and the second arm 51. Therefore, the bent portion does not interfere with the surroundings.

[0091] (2) The second arm 51 has two shafts 52. The two shafts 52 are arranged side by side in the direction of gravity and inserted into the bearings 44 arranged side by side in the direction of gravity. Compared with the case where the second arm 51 has only one shaft 52 and the case where the two shafts 52 are arranged side by side in the horizontal direction, the rigidity of the second arm 51 in the direction of gravity is improved. Therefore, compared with the case where the second arm 51 has only one shaft 52 and the case where the two shafts 52 are arranged side by side in the horizontal direction, the amount of deflection of the shaft 52 in the direction of gravity can be reduced while reducing the mass of the second arm 51. As a result, the resistance generated between the shaft 52 and the bearings 44 when the shaft 52 moves linearly can be reduced, and therefore the operating force required when transporting the cargo can be further reduced.

[0092] (3) When the arm-type assist device 11 is stopped, the first to third brake mechanisms 161 to 163 are activated. This makes it possible to suppress the rotation of the first rotation support part 21 and the second rotation support part 61 due to inertia, and the linear movement of the shaft 52. Compared to a case where no brake mechanisms are provided, it is possible to shorten the time until the movement of the arm-type assist device 11 stops when operation by the operating part 71 is stopped, and it is possible to position the operating part 71 at a desired position.

[0093] (4) The second arm 51 is equipped with a second brake mechanism 162. The shaft braking portion 162b of the second brake mechanism 162 is arranged in parallel with the bearing 44 in the direction of gravity. For this reason, the rigidity of the second arm 51 is increased by the bearing 44 and the shaft braking portion 162b. As a result, the amount of flexure when the second arm 51 is moved linearly can be reduced.

[0094] (5) The second arm 51 has a shaft insertion member 55. A swing hole 55a extending longitudinally in the direction of gravity is formed in this shaft insertion member 55, and the front end of the braking shaft 162a is inserted into the swing hole 55a. This allows the braking shaft 162a to bend in the direction of gravity by the swing hole 55a.

[0095] (6) In the second brake mechanism 162, the braking shaft 162a is supported by the shaft braking portion 162b and also by a pair of shaft supports 162c. The braking shaft 162a and the pair of shaft supports 162c can reduce the sliding resistance caused by bending of the braking shaft 162a, thereby reducing the operating force.

[0096] (7) The brake shaft 162a has a smaller diameter than the shaft 52. For example, the second brake mechanism 162 included in the second arm 51 can be made lighter than when the brake shaft 162a has the same diameter as the shaft 52. As a result, the operability of the second arm 51 can be improved.

[0097] (8) The second arm 51 has a swing support part 56 provided at the front end of the shaft 52, and a swing member 59 supported by the swing support part 56 so as to be swingable in the front-rear direction. The second rotation support part 61 is fixed to the swing member 59. The swing restriction part 80 restricts the swing angle of the swing member 59 in the front-rear direction. This allows the minimum necessary degree of freedom for the swing of the operating part 71 only against the bending of the second arm 51 in the gravity direction. As a result, the operating part 71 can be maintained horizontally, so that the horizontality of the load held by the operating part 71 can be maintained and the vibration of the operating part 71 due to the inertia of the load can be suppressed.

[0098] (9) The bearing 44 is fixed to the upper surface 42b of the fixed base 42. The fixed position of the bearing 44 can be adjusted along the upper surface 42b of the fixed base 42. This allows the first arm 31 and the second arm 51 to be arranged in a straight line when viewed from above with the arm-type assist device 11 in the direction of gravity, and also allows the second arm 51 to be inclined relative to the first arm 31. This makes it possible to transport cargo while avoiding obstacles.

[0099] (10) The arm-type assistive device 11 is equipped with a cable bear 78. Various wirings and air piping are housed inside this cable bear 78. Therefore, the various wirings and air piping can be protected by the cable bear 78. Then, the case 78a moves linearly following the linear movement of the second arm 51, and the flexible part 78b is displaced. Therefore, even if the various wirings and air piping are displaced following the linear movement of the second arm 51, the various wirings and air piping can be protected by the cable bear 78.

[0100] (11) The case 78a of the cable bear 78 is disposed to the side of the upper shaft 52, rather than directly above the upper shaft 52. Compared to when the case 78a is disposed directly above the upper shaft 52, the height of the case 78a can be made lower.

[0101] (12) The swing restriction portion 80 has a restriction protrusion 82. The restriction protrusion 82 can adjust the amount of projection of the restriction bolt 83 from the extension piece 81a toward the branch portion 59b by adjusting the amount of screwing of the restriction bolt 83 into the nut 84. The amount of projection of the restriction bolt 83 is adjusted to adjust the size of the gap between the head of the restriction bolt 83 and the branch portion 59b, thereby restricting the swing angle of the swing member 59 in the front-rear direction. As a result, the swing angle of the swing member 59 restricted by the swing restriction portion 80 can be adjusted.

[0102] This embodiment can be modified as follows: This embodiment and the following modifications can be combined with each other to the extent that there is no technical contradiction. 12, the braking shaft 162a of the second brake mechanism 162 may be formed by one of the two shafts 52 of the second arm 51. In this case, the shaft braking portion 162b may be installed in the bearing 44 that supports one of the shafts 52 functioning as the braking shaft 162a.

[0103] As shown in FIG. 13, the brake shaft 162a of the second brake mechanism 162 may be disposed between two shafts 52 arranged side by side in the direction of gravity. When two shafts 52 are arranged side by side in the direction of gravity, the amount of deflection of second arm 51 can be reduced as the distance in the direction of gravity between two shafts 52 increases. In addition, since shaft braking portion 162b is disposed between two shafts 52, the rigidity of second arm 51 can be increased by shaft braking portion 162b.

[0104] Furthermore, when the braking shaft 162a is disposed above the upper shaft 52, the shaft braking portion 162b also protrudes upward from the upper shaft 52. However, since the shaft braking portion 162b is disposed between the two shafts 52, an increase in the dimension of the second arm 51 in the direction of gravity can be suppressed.

[0105] The pivotable member 59 may be supported so as to be non-pivotable relative to the pivot support member 57. In this case, the second rotation support portion 61 fixed to the pivotable member 59 is non-pivotable in the front-rear direction. In that case, the pivot restricting portion 80 may not be provided.

[0106] The diameter of the brake shaft 162a may be the same as the diameter of the shaft 52, or may be larger than the diameter of the shaft 52. The shaft insertion member 55 at the front end of the second arm 51 may be omitted. In this case, since there is no swing hole 55a, the front end of the brake shaft 162a may be a free end or may be fixed to a separate member.

[0107] The arm-type assist device 11 does not necessarily have to include the first to third brake mechanisms 161 to 163. The configuration of the first brake mechanism 161 may be changed as long as it is possible to prohibit rotation of the first rotation support part 21. The configuration of the second brake mechanism 162 may be changed as long as it is possible to prohibit linear movement of the shaft 52. The configuration of the third brake mechanism 163 may be changed as long as it is possible to prohibit rotation of the operation part 71.

[0108] The shafts 52 may be arranged side by side in the horizontal direction. In this case, the bearings 44 are arranged side by side in the horizontal direction on the upper surface 42b of the fixed base 42. The second arm 51 may have one or three shafts 52. [Explanation of symbols]

[0109] 11...arm-type assistive device, 12...base, 21...first rotating support part, 22...first support part, 23...second support part, 31...first arm, 35...first end, 36...second end, 41...fixed support part, 44...bearing, 51...second arm, 52...shaft, 55...shaft insertion member, 55a...swing hole, 56...swing support part, 59...swing member, 61...second rotating support part, 71...operating part, 80...swing regulating part, 90...actuator, 161...first brake mechanism, 162...second brake mechanism, 162a...brake shaft, 162b...shaft braking part, 163...third brake mechanism.

Claims

1. The base and a first arm having a first support part at a first end in an axial direction and a second support part at a second end in the axial direction, the second support part being capable of swinging in a vertical direction parallel to the first support part by a parallelogram link, the first arm incorporating an actuator-assisted mechanism; a first rotation support portion having a rotation center on a first vertical axis, the first rotation support portion rotatably supporting the first support portion on the base; a fixed support part fixed to the second support part and having a horizontal upper surface; a bearing fixed to the upper surface of the fixed support; a second arm supported by the fixed support portion through the bearing, the second arm having a shaft that is linearly movable in a horizontal direction by the bearing; a second rotation support portion supported by a front end of the shaft of the second arm and having a second vertical axis as a rotation center; an operation unit rotatably supported by the second rotation support unit, The bearings are arranged in a plurality of parallel rows in the direction of gravity, The second arm has a plurality of shafts, each of which is supported by the fixed support portion via the bearing, and the plurality of shafts are arranged in parallel in the direction of gravity.

2. The arm-type assist device according to claim 1 , wherein each of the first rotation support portion, the second rotation support portion and the second arm is provided with a brake mechanism.

3. 3. The arm-type assist device according to claim 2, wherein the brake mechanism of the second arm has a brake shaft and a shaft braking part, the brake shaft extends horizontally parallel to the shaft and is supported by the shaft braking part, and the brake shaft is capable of linear movement in the horizontal direction integral with the shaft.

4. The base and a first arm having a first support part at a first end in an axial direction and a second support part at a second end in the axial direction, the second support part being capable of swinging in a vertical direction parallel to the first support part by a parallelogram link, the first arm incorporating an actuator-assisted mechanism; a first rotation support portion having a rotation center on a first vertical axis, the first rotation support portion rotatably supporting the first support portion on the base; a fixed support part fixed to the second support part and having a horizontal upper surface; a bearing fixed to the upper surface of the fixed support; a second arm supported by the fixed support portion through the bearing, the second arm having a shaft that is linearly movable in a horizontal direction by the bearing; a second rotation support portion supported by a front end of the shaft of the second arm and having a second vertical axis as a rotation center; an operation unit rotatably supported by the second rotation support unit, each of the first rotation support portion, the second rotation support portion, and the second arm includes a brake mechanism; the brake mechanism of the second arm has a brake shaft and a shaft braking part, the brake shaft extends in a horizontal direction parallel to the shaft and is supported by the shaft braking part, and the brake shaft is linearly movable in the horizontal direction integrally with the shaft, The second arm has a plurality of shafts, the plurality of shafts being arranged in parallel in the direction of gravity, and the shaft braking portion is disposed between the shafts arranged in the direction of gravity.

5. 5. An arm-type assist device as described in claim 3 or claim 4, wherein the second arm has an axis insertion member at its front end, the axis insertion member has a swing hole extending longitudinally in the direction of gravity, and the front end of the brake shaft is inserted into the swing hole.

6. 6. The arm-type assist device according to claim 3, wherein the braking shaft has a smaller diameter than the shaft.

7. the second arm has a swing support part provided at a front end of the shaft and a swing member supported on the swing support part so as to be swingable in a front-rear direction, the second rotation support part being supported by the swing member, The arm-type assisting device according to any one of claims 1 to 6, further comprising a swing regulating portion for regulating a swing angle of the swinging member in the forward and backward directions.

8. The arm-type assist device according to any one of claims 1 to 7, wherein the fixed position of the bearing is adjustable along the upper surface of the fixed support part.

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