Industrial robot and robotic piping structure

Abstract

To provide an industrial robot with an arm capable of accommodating a piping structure of piping members and the like, in which contribution is made to facilitation of sanitation management and protection of the piping structure of the piping members and the like, as well as, other robotic components accommodated in the arm.SOLUTION: An arm 31 of an industrial robot incorporates a piping part 43 connecting a suction pad attached to a finger tip of the arm 31 and a suctioning pump. The piping part 43 comprises a first piping member 51A, a second piping member 51B, and a piping joint 55 coupling those members. The piping joint 55 includes a first joint 60 fitted to an end of the first piping member 51A, and a second joint 80 fitted to an end of a second piping member 51B. A joint main body of the second joint 80 is provided with an insertion part to be inserted into an insertion hole formed in a joint main body of the first joint 60. When the insertion part is inserted into the insertion hole, both joints 60, 80 are sealed between an inner peripheral surface of the insertion hole and an outer peripheral surface of the insertion part, and separation of both joints 60, 80 is regulated.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to an industrial robot and a piping structure applied to an industrial robot. [Background technology]

[0002] Some industrial robots with articulated arms are capable of mounting a hand at the end of the arm to hold a workpiece. Hands of this type include those configured to hold a workpiece between multiple fingers, and those configured to adsorb a workpiece using a suction pad (suction unit) connected to a pump via a piping member (see, for example, Patent Document 1). For industrial robots equipped with suction-type hands, a proposal has been made to accommodate the piping member inside the arm to improve workability when cleaning the exterior of the industrial robot (see, for example, Patent Document 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2004-291132 A [Patent Document 2] JP 2019-147236 A Summary of the Invention [Problem to be solved by the invention]

[0004] Here, when the above-mentioned suction-type hand is used in fields such as medical care and food manufacturing, it is preferable to sterilize the piping members (flow paths) to suppress the growth of bacteria. For example, if a sterilizing gas (fluid) such as hydrogen peroxide is sucked from a suction pad and flows into the piping members, the sterilization work can be performed without removing the piping members. This is advantageous in terms of improving the efficiency of the sterilization work. However, some sterilizing gases are corrosive, and there is a concern that the sterilizing gas leaking from the piping members housed in the arm may corrode other robot parts (wiring, connectors, boards, sensors, etc.) in the arm. This is not preferable because it may cause a decrease in durability of the industrial robot or a malfunction. In particular, when the piping members are housed in the arm, it is reasonable to form a flow path using multiple piping members and piping joints that connect these piping members due to the characteristics of the arm, but it is assumed that the above-mentioned leakage is likely to occur at the connection points of the piping members in such a piping structure. In addition, when the piping members and piping joints are housed in the arm together with other robot parts, these robot parts may interfere with the connection work of the piping members, making the connection work difficult. This can lead to operational errors, and imperfect connections due to operational errors can lead to leakage of sterilizing gas. As described above, there is still room for improvement in the configuration of the piping structure of the industrial robot in terms of facilitating sanitation management of the industrial robot and protecting the piping structure such as the piping members as well as other robot parts housed within the arm.

[0005] The present invention has been made in consideration of the problems exemplified above, and its main objective is to contribute to facilitating hygiene management for industrial robots capable of housing piping structures such as piping components in their arms, and to protecting other robot parts that are housed in the arms along with the piping structures such as piping components. [Means for solving the problem]

[0006] Means for solving the above problems will be described below.

[0007] First means: A piping structure for a robot that is applied to an industrial robot having an arm with a plurality of joints, and that forms a flow path within the arm that connects a suction part attached to the tip of the arm and a suction pump, a plurality of piping members constituting the flow path and a piping joint connecting the piping members in a series; The plurality of piping members include a first piping member and a second piping member, As the piping joint, a first joint having a first body portion that configures the flow path, the first piping member being attached to one end of the first body portion in a flow direction of the flow path; a second joint having a cylindrical second body portion inserted into an insertion hole formed at the other end of the first body portion and constituting a part of the flow path together with the first joint; Including, the first joint and the second joint are corrosion-resistant to a sterilization fluid flowing through the flow path during sterilization of the robot piping structure, and are configured such that, when the second body part is inserted into the insertion hole of the first body part, a seal is formed between an outer peripheral surface of a portion of the second body part inserted into the insertion hole and an inner peripheral surface of the insertion hole, and separation of the first joint and the second joint is restricted; The inner circumferential surface of the second piping member is configured to be a corrosion-resistant layer having higher corrosion resistance than a base layer of the second piping member, The second joint is formed such that a part of the second body portion extends from the insertion hole in the state in which separation is restricted, and an attachment portion to which a second piping member is attached is provided on the extending part, The mounting portion of the second joint is inserted into the second piping member, and the second joint and the second piping member are sealed between an outer peripheral surface of the mounting portion and an inner peripheral surface of the second piping member.

[0008] According to the configuration shown in the first means, by inserting the second body part of the second joint into the insertion hole of the first joint, the first joint and the second joint are sealed between the inner circumferential surface of the insertion hole of the first body part and the outer circumferential surface of the second body part, and separation of the two joints is restricted. In this way, simplifying the work of connecting the first piping member and the second piping member is preferable in terms of improving the work efficiency and suppressing the work error when performing the work (assembly work of the piping structure) in the limited space in the arm. In addition, the attachment work (advance preparation) of the second piping member to the second joint does not need to be performed in the narrow space in the arm, but can be performed in the wide space outside the arm. Therefore, the constraints on the use of fixtures and tools when attaching the second piping member to the second joint can be relaxed. This is preferable in terms of firmly fixing the second piping member and the second joint and suppressing the leakage of the sterilization fluid from the boundary part between the second piping member and the second joint.

[0009] The second piping member has a multi-layer structure with a corrosion-resistant layer provided on the inner peripheral surface side. This configuration allows for greater freedom in the material of the base layer of the second piping member while providing corrosion resistance. This is preferable in terms of optimizing the elasticity and flexibility of the second piping member, easing restrictions on piping arrangement, and improving the durability of the second piping member. In addition, the second joint and the second piping member are sealed between the outer peripheral surface of the second main body and the inner peripheral surface of the second piping member. This suppresses corrosion of the portion (outer peripheral surface) of the second piping member that has low corrosion resistance, and suppresses the seal of the second piping member from being weakened due to the corrosion. In addition, both the first joint and the second joint have corrosion resistance. Therefore, even if sterilization gas enters the boundary between the inner peripheral surface of the first joint (insertion hole) and the outer peripheral surface of the second joint, corrosion of the first joint and the second joint due to the corrosion can be avoided, and the seal of both joints can be suppressed from being weakened due to the corrosion. The above-described configuration can prevent leakage of sterilizing fluid into the arm, thereby contributing to the protection of other robot parts housed within the arm.

[0010] According to the configuration shown in the first aspect, sterilization (decontamination) of piping members, piping joints, etc. is possible by sucking sterilizing fluid from the suction part while the piping members, etc. are attached to the arm. This contributes to facilitating sanitation management of industrial robots. Furthermore, since there is no need to detach piping members, etc. every time a sterilization operation is performed, an increase in the workload due to an increase in the frequency of sterilization operations to strengthen sanitation management can be suitably suppressed.

[0011] Second means: A device having an arm with multiple joints formed therein; An industrial robot in which a suction unit that sucks a workpiece is attached to a tip of the arm, and a robot piping structure that forms a flow path connecting the suction unit and a suction pump is disposed inside the arm, The robot piping structure includes a first piping member, a second piping member, and a piping joint that connects the piping members in a series, As the piping joint, a first joint having a first body portion that configures the flow path, the first piping member being attached to one end of the first body portion in a flow direction of the flow path; a second joint having a cylindrical second body portion inserted into an insertion hole formed at the other end of the first body portion and constituting a part of the flow path together with the first joint; Including, the first joint and the second joint are corrosion-resistant to a sterilization fluid flowing through the flow path during sterilization of the robot piping structure, and are configured such that, when the second body part is inserted into the insertion hole of the first body part, a seal is formed between an outer peripheral surface of a portion of the second body part inserted into the insertion hole and an inner peripheral surface of the insertion hole, and separation of the first joint and the second joint is restricted; The inner circumferential surface of the second piping member is configured to be a corrosion-resistant layer having higher corrosion resistance than a base layer of the second piping member, The second joint is formed such that a part of the second body portion extends from the insertion hole in the state in which separation is restricted, and an attachment portion to which a second piping member is attached is provided on the extending part, The mounting portion of the second joint is inserted into the second piping member, and the second joint and the second piping member are sealed between an outer peripheral surface of the mounting portion and an inner peripheral surface of the second piping member.

[0012] The configuration shown in the second aspect can contribute to facilitating sanitary management of the industrial robot and protecting other robot parts housed within the arm. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 is a schematic diagram showing a robot system. [Diagram 2] FIG. 2 is a block diagram showing the electrical configuration of the robot system. [Diagram 3] FIG. 1 is a schematic diagram showing the decontamination of a piping section. [Figure 4] FIG. [Diagram 5] FIG. 1 is a schematic diagram for explaining a problem. [Figure 6] An enlarged view of the robot. [Figure 7] FIG. 4 is a partially enlarged view of a piping section showing a piping joint and its surroundings. [Figure 8] FIG. [Figure 9] Exploded view of the piping section. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, an embodiment of a robot system used in a pharmaceutical manufacturing factory or the like will be described with reference to the drawings.

[0015] 1, the robot system 10 includes a robot 15, which is a vertical articulated industrial robot. The main body (robot main body 21) of the robot 15 includes a base 22 fixed to a pedestal or the like, a shoulder 23 supported by the base 22, a lower arm 24 supported by the shoulder 23, a first upper arm 25 supported by the lower arm 24, a second upper arm 26 supported by the first upper arm 25, a wrist 27 supported by the second upper arm 26, and a flange 28 supported by the wrist 27.

[0016] The base portion 22 and the shoulder portion 23 are formed with a first joint portion that connects the base portion 22 and the shoulder portion 23, and the shoulder portion 23 is rotatable in the horizontal direction around the connecting axis (first axis AX1) of the first joint portion. The shoulder portion 23 and the lower arm portion 24 are formed with a second joint portion that connects the shoulder portion 23 and the lower arm portion 24, and the lower arm portion 24 is rotatable in the vertical direction around the connecting axis (second axis AX2) of the second joint portion. The lower arm portion 24 and the first upper arm portion 25 are formed with a third joint portion that connects the lower arm portion 24 and the first upper arm portion 25, and the first upper arm portion 25 is rotatable in the vertical direction around the connecting axis (third axis AX3) of the third joint portion. The first upper arm portion 25 and the second upper arm portion 26 are formed with a fourth joint portion that connects the first upper arm portion 25 and the second upper arm portion 26, and the second upper arm portion 26 is rotatable in a twisting direction around the connecting axis (fourth axis AX4) of the fourth joint portion. The second upper arm portion 26 and the wrist portion 27 are formed with a fifth joint portion that connects the second upper arm portion 26 and the wrist portion 27, and the wrist portion 27 is rotatable in a vertical direction around the connecting axis (fifth axis AX5) of the fifth joint portion. The wrist portion 27 and the flange portion 28 are formed with a sixth joint portion that connects the wrist portion 27 and the flange portion 28, and the flange portion 28 is rotatable in a twisting direction around the connecting axis (sixth axis AX6) of the sixth joint portion.

[0017] The shoulder section 23, the lower arm section 24, the first upper arm section 25, the second upper arm section 26, the wrist section 27, and the flange section 28 are arranged in a series to form an arm 31 in the robot body 21. In the arm 31, a motor unit is provided for each joint, the motor unit including a servo motor and a reducer for driving the joints as an electric actuator for rotating each joint, a rotary encoder for detecting the rotation angle of each joint (axis), a non-excitation operating electromagnetic brake, and a motor control board (servo amplifier) ​​for controlling the drive of the servo motor.

[0018] A vacuum-type suction pad 42 is attached as an end effector to the flange portion 28 constituting the tip (hand tip) of the arm 31. The suction pad 42 is connected to a pump 44 via a piping portion 43 built into the arm 31, and air is sucked from the suction pad 42 by operating the pump 44. For example, the pump 44 is operated to generate negative pressure while the suction pad 42 is pressed against the workpiece W, so that the workpiece W is sucked onto the suction pad 42. The suction pad 42, the piping portion 43, and the pump 44 constitute a suction device 41. The robot 15 shown in this embodiment is provided next to the conveyor C that transports the workpiece W, and performs a boxing operation for the workpiece W transported by the conveyor C.

[0019] Here, a supplementary explanation will be given on the electrical configuration of the robot system 10 with reference to Fig. 2. The robot system 10 includes a robot controller 16 as an overall control device, and the motor control board 35 and the pump 44 described above are connected to the robot controller 16.

[0020] A servo motor 36 and a rotary encoder 37 are connected to the motor control board 35, and the motor control board 35 receives an operation instruction for a task from the robot controller 16 and specifies an operation target position. Then, the motor control board 35 controls the drive of the servo motor 36 based on the operation target position and position data acquired from the rotary encoder 37, i.e., the encoder value indicating the rotation angle (rotation position) of the servo motor 36.

[0021] Each motor unit of the robot 15 is provided with a force sensor 38, which is a torque detection sensor that detects torque generated at a joint. The force sensor 38 includes a plurality of strain gauges arranged on the reducer, and a detection section connected to each strain gauge via a lead wire. Each detection section includes a bridge circuit section, which is an electric circuit suitable for detecting minute changes in resistance value, and an amplifier section that amplifies each signal detected by the bridge circuit section. The amplified signal is transmitted to a motor control board 35 mounted on the motor unit. The motor control board 35 is capable of decelerating or stopping (including a protective stop) the robot 15 in response to a signal (detected torque) from the force sensor 38, thereby improving the safety of the robot system 10.

[0022] The robot controller 16 also controls the driving of the pump 44 to pick / place the workpiece W. As described above, the robot 15 shown in this embodiment is used in a pharmaceutical manufacturing plant, and therefore, as part of the sanitation management of the robot 15, the pump 44 is controlled to drive and sterilize the suction pad 42, piping 43, and the like. Specifically, as shown in Fig. 3, the pump 44 is controlled to suck in a gas for decontaminating bacteria and other germs (e.g., sterilizing gas such as hydrogen peroxide or sodium hypochlorite) from the suction pad 42, thereby performing the decontamination process.

[0023] Some of these types of sterilization gases are corrosive. Therefore, if the sterilization gas leaks into the arm 31, it may affect various components housed in the arm 31, such as the wiring, connectors, and motor control board 35. If the leaked sterilization gas corrodes these components, it may cause inconveniences such as a decrease in durability of the robot 15 and abnormal operation. Although housing the piping section 43 inside the arm 31 is advantageous in suppressing the generation of foreign matter caused by contact (collision) of the piping section 43 and in suppressing the piping section 43 from getting in the way when cleaning the robot 15, thereby improving the efficiency of the cleaning work, it is expected that the impact of leakage of the sterilization gas will be greater than when a configuration corresponding to the piping section 43 is disposed outside the arm 31.

[0024] Incidentally, when piping section 43 is housed in articulated arm 31, piping section 43 is constructed using a plurality of piping members 51 and piping joints 55 that connect these piping members 51, thereby making it possible to rationally form flow path F (see FIG. 3) for adsorption device 41. However, in such a configuration, the above-mentioned leakage of sterilizing gas is likely to occur at the connection points of piping members 51. In other words, when piping section 43 is disposed outside arm 31, a flow path can be easily formed without dividing the piping section into a plurality of members, and it can be said that leakage of sterilizing gas at the connection points of the piping members is a particularly noteworthy issue in a configuration in which piping section 43 is housed in arm 31.

[0025] In this embodiment, taking these circumstances into consideration, the configuration of the piping section 43 is devised. First, a supplementary explanation will be given of the cylindrical piping member 51 constituting the piping section 43 with reference to the schematic diagram of Fig. 4. Note that, although a plurality of piping members 51 are used in this embodiment, each piping member 51 has the same configuration.

[0026] The piping member 51 is made of polyurethane. Making the piping member 51 from polyurethane is preferable in terms of providing the piping member 51 with a certain degree of stiffness (elasticity) to facilitate its handling within the arm 31 and improving its ability to follow changes in the posture of the robot 15. On the other hand, polyurethane has the property of having low resistance to sterilization gases such as hydrogen peroxide gas described above. Therefore, the base layer 52 of the piping member 51 is formed from polyurethane, and the inside of the piping member 51 is coated with fluorine, which has higher resistance (corrosion resistance, chemical resistance) to sterilization gases than polyurethane. That is, the inner circumferential surface 51a is formed from the coating layer 53, and the piping member 51 has a two-layer structure (laminated type) of the base layer 52 and the coating layer 53. This prevents the piping member 51 from corroding from the inside due to the sterilization gas flowing through the piping. Incidentally, it is preferable that the thickness of the coating layer 53 is smaller than that of the base layer 52.

[0027] Incidentally, by making the entire piping member out of fluororesin, the corrosion resistance can be significantly improved. However, fluororesin is harder than polyurethane, and if the entire piping member is made of fluororesin, the flexibility of the piping member will be low. For this reason, if the piping member is made to follow the various movements (bending and twisting) of the arm 31, it is expected that the piping member will be easily broken or it will be difficult to ensure the durability of the piping member. Therefore, there is technical significance in making the piping member 51 a laminated type as described above and keeping the part having corrosion resistance on the inner peripheral surface side.

[0028] Here, we will explain the problems associated with a piping structure including the above-mentioned piping member 51. Fig. 5(a) illustrates an example in which a one-touch joint 100 is used as a piping joint, and Fig. 5(b) illustrates an example in which a bamboo shoot joint 200 is used as a piping joint.

[0029] 5(a) has a cylindrical main body 101, and one end of the main body 101 is formed with an insertion hole 105 into which the piping member 51 is inserted, and a stopper 106 that abuts against the tip of the piping member 51 inserted into the insertion hole 105 to prevent further insertion. The main body 101 is provided with an elastic sleeve 107 as a sealant that abuts against the outer circumferential surface 51b of the piping member 51 inserted into the insertion hole 105 and the inner circumferential surface 105a of the insertion hole 105, and the elastic sleeve 107 seals the one-touch joint 100 and the piping member 51 between the inner circumferential surface 105a of the insertion hole 105 and the outer circumferential surface 51b of the piping member 51. A locking claw 108 is provided at a position on the entrance 105c side of the insertion hole 105 with respect to the elastic sleeve 107, which catches (bites into) the outer peripheral surface 51b of the piping member 51 to prevent separation of the one-touch fitting 100 and the piping member 51 (falling off of the piping member 51).

[0030] According to this one-touch joint 100, by inserting a piping member 51 into an insertion hole 105 formed in a main body 101, separation of the one-touch joint 100 and the piping member 51 is restricted, and the one-touch joint 100 and the piping member 51 are sealed together. Making the piping member 51 easily attachable in this way is preferable in terms of preventing the assembly work of the piping section to the robot 15 from becoming complicated and preventing poor connections due to operational errors.

[0031] Here, the contact point (seal point) of the elastic sleeve 107 on the piping member 51 is the outer circumferential surface 51b of the piping member 51, and in the above-mentioned simple mounting structure of the piping member 51, a slight gap may occur at the boundary between the piping member 51 and the main body 101. Therefore, it cannot be denied that the sterilization gas flowing into the boundary may come into contact with the outer circumferential surface 51b of the piping member 51. As described above, the outer circumferential surface 51b of the piping member 51 is made of the base layer 52 (polyurethane), and therefore, there is a concern that the piping member 51 may be corroded gradually from the outer circumferential surface 105b side. If the corrosion progresses and the gap at the boundary becomes larger, the seal by the elastic sleeve 107 becomes weak, and there is a concern that the sterilization gas may easily leak through the boundary. In addition, separation (falling off) of the piping member 51 is prevented by the locking claws 108 hooked onto the outer peripheral surface 51b of the piping member 51. However, as corrosion of the piping member 51 progresses, the preventing function of the locking claws 108 will no longer be effective, and there is a concern that this will make it easier for the piping member 51 to fall off.

[0032] It is possible to provide corrosion resistance to the outer peripheral surface 51b of the piping member 51 by forming a coating layer on it in the same way as on the inner peripheral surface 51a, but the outer peripheral surface 51b may be scraped or peeled off due to contact with the lock claws 108. In other words, although corrosion can be suppressed to a certain degree by forming a coating layer on the outer peripheral surface 51b as well, it is difficult to fully exert the effect, and the reliability of protecting other robot parts is reduced.

[0033] Corrosion from the outer circumferential surface 51b side of the piping member 51 can be eliminated by using, for example, a bamboo shoot joint 200 shown in Fig. 5(b). The reason for this will be explained below.

[0034] The bamboo shoot joint 200 has a cylindrical main body 201, and one end of the main body 201 is an insertion part 202 that is inserted into the piping member 51. The bamboo shoot joint 200 also has a nut 205 that sandwiches the piping member 51 into which the insertion part 202 is inserted between the main body 201 and the insertion part 202, and the main body 201 is formed with a threaded part 203 (male thread) that engages with a threaded part (female thread) of the nut 205. With the nut 205 passing through the piping member 51, the insertion part 202 is inserted into the piping member 51, and the nut 205 is tightened (crimped), thereby restricting separation of the piping member 51 and the bamboo shoot joint 200. The bamboo shoot joint 200 and the piping member 51 are sealed between the outer circumferential surface 202b of the insertion portion 202 and the inner circumferential surface 51a of the piping member 51, so that it is possible to prevent the sterilizing gas from coming into contact with the outer circumferential surface 51b of the piping member 51. This makes it possible to prevent corrosion from progressing from the outer circumferential surface 51b side of the piping member 51.

[0035] Although this configuration is superior to the one-touch joint 100 shown in FIG. 5(a) in terms of suppressing corrosion of the piping member 51, when assembling the piping section, it is necessary to insert a tool such as a wrench into the arm 31 of the piping member 51 while avoiding other robot parts, and tighten the nut 205, which makes the work more difficult than simply inserting the piping member 51 into the insertion hole 105. In addition, securing a space for inserting the tool may make it difficult to coexist the piping section and other robot parts in the arm 31, or to make the robot 15 more compact. Furthermore, when connecting the piping member 51 to the bamboo shoot joint 200 fixed to the arm 31 (bracket), the piping member 51 is twisted as the nut 205 is tightened, and a torsional stress remains in the piping member 51 after the connection of the piping member 51 is completed. If such stress remains, it may be a factor that reduces the durability of the piping member 51.

[0036] The bamboo shoot joint 200 is provided with a screw portion 204 on the other end side of the main body portion 201 for fixing the bamboo shoot joint 200 to the bracket of the arm 31. This configuration eliminates the need for a fastener for fixing the bamboo shoot joint 200 to the bracket, and simplifies the configuration for fixing. Here, for example, it is possible to attach the bamboo shoot joint 200 to the piping member 51, and then fix the bamboo shoot joint 200 to the arm 31 (bracket). However, even in this case, torsional stress remains in the piping member 51 due to the tightening of the screw portion 204.

[0037] In this embodiment, one of the features is that, in consideration of the circumstances illustrated in Figs. 5(a) and (b), the piping section 43 is easily decontaminated, thereby reducing the burden of sanitation management, while measures are taken to ensure the durability of the piping section 43 and to protect various robot parts in the arm 31. Hereinafter, a specific configuration of the piping section 43 in this embodiment will be described with reference to Figs. 6 to 9. Note that the piping section 43 is composed of a plurality of piping members 51 and a piping joint 55 that connects the piping members 51. However, in the following description, for convenience, the piping member 51 located on the tip side of the arm 31 with respect to the piping joint 55 will be appropriately distinguished as the "first piping member 51A" and the piping member 51 located on the base end side of the arm 31 with respect to the piping joint 55 as the "second piping member 51B".

[0038] As shown in FIG. 6, the housing 32 constituting the outer shell of the arm 31 is provided with an opening 33a of a substantially rectangular shape elongated in the longitudinal direction of the arm 31 and a cover 33b covering the opening 33a, and is configured so that the inside of the arm 31 can be accessed by removing the cover 33b. The opening 33a is a so-called service hole, and is arranged in the middle part in the longitudinal direction of the arm 31 (specifically, the lower arm part 24), and a pipe joint 55 of the pipe part 43 is located in this opening 33a. Specifically, a bracket 34 for fixing the pipe part 43 (specifically, the pipe joint 55) to the housing 32 is provided near the short side part (the short side part on the hand tip side) of the opening 33a. Note that, for convenience of explanation, a part of the cover 33b is broken away in FIG. 6.

[0039] 7 and 8, the piping joint 55 shown in this embodiment is composed of a first joint 60 similar to the one-touch joint 100 shown in Fig. 5(a) above, and a second joint 80 that forms a pair with the first joint 60, and the first joint 60 and the second joint 80 are connected (coupled) in a state in which the first joint 60 is attached to one end of the first piping member 51A and the second joint 80 is attached to one end of the second piping member 51B, thereby connecting (joining) the first joint 60 and the second joint 80 to connect the first piping member 51A and the second piping member 51B to each other in a continuous manner. Below, the second joint 80 will be described, and then the first joint 60 will be described.

[0040] 8 and 9, the second joint 80 includes a cylindrical joint body 81 which, together with the second piping member 51B, forms a flow path F of the piping section 43, and an expanded diameter section 82 is formed in the middle section of the joint body 81 so as to bulge in a direction intersecting with the central axis CL2 of the joint body 81. That is, the joint body 81 has a stepped cylindrical shape with an expanded diameter at its middle section.

[0041] An attachment portion 83 to which the second piping member 51B is attached is formed on one end side (reduced diameter portion) of the joint body 81, and an insertion portion 84 to be inserted into the first joint 60 (insertion hole 65 described later in detail) is formed on the other end side (reduced diameter portion) of the joint body 81. In other words, the joint body 81 is roughly divided into three parts: the insertion portion 84, the enlarged diameter portion 82, and the attachment portion 83.

[0042] The outer diameter of the mounting portion 83 is formed to be slightly larger than the inner diameter of the second piping member 51B, and the mounting portion 83 is inserted into the second piping member 51B so that an outer peripheral surface 83b of the mounting portion 83 comes into contact with an inner peripheral surface 51a of the second piping member 51B. The second joint 80 also includes a nut 91 which is a fixture that clamps (crimps) the second piping member 51B between the mounting portion 83 and the second joint 80.

[0043] A body-side threaded portion 86 (male thread) that engages with a nut-side threaded portion 92 (female thread) formed on an inner peripheral surface 91a of the nut 91 is formed on a portion of the expanded diameter portion 82 that faces the mounting portion 83. The nut-side threaded portion 92 is also not formed on the entire inner peripheral surface 91a of the nut 91, but is limited to one end side of the nut 91. In other words, when the nut 91 is fastened, the nut-side threaded portion 92 of the nut 91 engages with the body-side threaded portion 86, while a portion of the other end side of the nut 91 is prevented from engaging with the body-side threaded portion 86, and faces the outer peripheral surface 83b of the mounting portion 83 across the second piping member 51B.

[0044] An opening flange 93 is formed on the other end of the nut 91 so as to protrude inward, and an annular protrusion 88 is formed on the middle portion of the attachment portion 83 so as to protrude in the radial direction of the central axis line CL1. The annular protrusion 88 is configured to be slightly separated from the opening flange 93 when the nut 91 is in a state in which the tightening is completed. After the attachment portion 83 of the joint body 81 is inserted into the second piping member 51B with the second piping member 51B inserted through the nut 91, the nut 91 is tightened, whereby the second piping member 51B bites into the annular protrusion 88 and the opening flange 93, and separation of the second piping member 51B and the second joint 80 is restricted. When separation of the second piping member 51B and the second fitting 80 is restricted, the opening flange 93 is located near the annular protrusion 88 (see Figure 8), and the opening flange 93 presses the second piping member 51B toward the mounting portion 83, thereby preventing a gap from occurring between the inner surface 51a of the second piping member 51B and the outer surface 83b of the mounting portion 83 (boundary portion BP2).

[0045] In addition, a square section 87 (see FIG. 7) with a hexagonal cross section is formed on the portion of the expanded diameter section 82 that faces the insertion section 84 as an engagement section that engages with a tool such as a wrench. This is a device to make it easier to apply force using a tool when tightening or loosening the nut 91.

[0046] The joint body 81 and the nut 91 shown in this embodiment are both made of a corrosion-resistant metal (more specifically, stainless steel). This prevents the sterilization gas flowing through the flow path F from causing corrosion of the second joint 80.

[0047] Next, a specific configuration of the first joint 60 will be additionally described in consideration of its relationship with the second joint 80.

[0048] The first joint 60 has a cylindrical joint body 61 which forms a flow path F together with the second joint 80. The joint body 61 is formed so that its central axis CL1 is coaxial with the central axis CL2 of the second joint 80 when the first joint 60 and the second joint 80 are combined (connected state). A connection part 62 for the first piping member 51A is provided on one end side of the joint body 61, and a connection part 63 for the second piping member 51B (second joint 80) is provided on the other end side. The specific configuration of the connection part 63 will be described below.

[0049] The connection portion 63 is formed with an insertion hole 65 into which the insertion portion 84 of the second joint 80 is inserted. The insertion hole 65 is coaxial with the central axis CL1 of the joint body 61, and a stopper 66 (more specifically, a step portion formed on the inner circumferential surface 84a) that determines the insertion position of the second joint 80 (insertion portion 84) is provided at the back of the insertion hole 65. When the first joint 60 and the second joint 80 are assembled together, the second joint 80 is pushed in until the tip of the second joint 80 (insertion portion 84) abuts against the stopper 66.

[0050] An inner peripheral surface 65a of the insertion hole 65 forms a circular ring shape coaxial with the central axis CL1, and the first joint 60 is fixed to the bracket 34 of the housing 32 so that an inlet portion 65c of the insertion hole 65 faces the center of the opening 33a. More specifically, the first joint 60 is fixed to the bracket 34 so that the central axis CL1 faces the longitudinal direction of the opening 33a (the longitudinal direction of the arm 31).

[0051] The insertion hole 65 is defined so that the inner diameter at the back side is approximately the same as the outer diameter of the insertion part 84, and is expanded so that the inner diameter at the inlet part 65c side is larger than that at the back side (hereinafter, also referred to as the expanded diameter part). That is, the insertion hole 65 has a stepped shape in which the inner diameter is larger at the inlet part 65c side. In the insertion hole 65, at a position between the stopper 66 and the inlet part 65c, specifically, at the expanded diameter part, an elastic sleeve 67 is disposed as a seal material that seals the first joint 60 and the second joint 80 between the inner peripheral surface 65a of the insertion hole 65 and the outer peripheral surface 84b of the insertion part 84. This elastic sleeve 67 prevents leakage of sterilization gas from the boundary part BP1 between the inner peripheral surface 65a of the insertion hole 65 and the outer peripheral surface 84b of the insertion part 84.

[0052] A lock claw 68 is provided at a position between the elastic sleeve 67 and the inlet portion 65c, more specifically, at the expanded diameter portion, as a restricting means for restricting separation between the first joint 60 and the second joint 80. The lock claw 68 is configured to protrude into the insertion route of the second joint 80 at the expanded diameter portion, and when the second joint 80 is inserted into the insertion hole 65, the lock claw 68 is elastically deformed by being pushed toward the inner circumferential surface 65a of the insertion hole 65 by the insertion portion 84 of the second joint 80. The lock claw 68 slides on the outer circumferential surface 84b of the insertion portion 84 of the second joint 80, and is caught in a groove portion 89 formed in the outer circumferential surface 84b of the insertion portion 84 just before the tip of the second joint 80 hits the stopper 66. The lock claw 68 is caught in the groove portion 89, restricting separation between the first joint 60 and the second joint 80.

[0053] The groove 89 shown in this embodiment has an annular shape centered on the central axis line CL2. This realizes a configuration in which there is no restriction on the phase when connecting the second joint 80 and the first joint 60. This is preferable in terms of suppressing the torsional stress from remaining in the second piping member 51B.

[0054] An operation ring 69, which is a release operation means operated by the user when separating the first joint 60 from the second joint 80, is disposed in the insertion hole 65 of the first joint 60 (more specifically, the expanded diameter portion). The operation ring 69 is held by the joint body 61 so as to be slidable in the axial direction of the central axis CL1, and a part of it extends from an entrance portion 65c of the insertion hole 65. This extending portion serves as a finger hook portion 69a on which the user hooks his or her finger when operating the operation ring 69.

[0055] The locking claw 68 is located on the movement path of the operation ring 69, and when a user places a finger on the finger hook portion 69a and pushes the operation ring 69 into the back side of the insertion hole 65, the locking claw 68 is pressed by the operation ring 69. The locking claw 68 is elastically deformed by being pressed by the operation ring 69, and moves away from the groove portion 89 of the second joint 80. As a result, the separation restriction by the locking claw 68 is released, and the second joint 80 can be pulled out of the insertion hole 65.

[0056] 8(a), when the first joint 60 and the second joint 80 are connected, a gap is formed between the finger hook portion 69a of the operation ring 69 and the expanded diameter portion 82 of the second joint 80. This makes it easier for the user to hook a finger on the operation ring 69 (finger hook portion 69a) when operating the operation ring 69.

[0057] The tip of the finger hook 69a is bent in a direction intersecting with the central axis CL1, and the distance L1 from the central axis CL1 to the tip is greater than the distance L2 from the central axis CL2 to the outer circumferential surface of the enlarged diameter portion 82 (specifically, the rectangular portion 87) and the distance L3 from the central axis CL2 to the outer circumferential surface of the nut 91. This is a measure to prevent the second joint 80 from interfering with the operation of the finger hook 69a.

[0058] In this embodiment, the connection structure of the first piping member 51A to the first joint 60 is the same as that of the second piping member 51B. That is, a joint corresponding to the second joint 80 is attached to the first piping member 51A, and the connection part 62 is provided with components corresponding to the insertion hole 65, the stopper 66, the elastic sleeve 67, the lock claw 68, and the operation ring 69, similar to the connection part 63. However, the specific connection structure between the first joint 60 and the first piping member 51A is arbitrary, and for example, it is also possible to adopt a configuration in which the connection part 62 of the first joint 60 is inserted into the first piping member 51A, and the first piping member 51A is fixed (crimped) to the first joint 60 using a nut, a band, or the like.

[0059] The joint body 61 and lock claw 68 constituting the first joint 60 are both made of corrosion-resistant metal (more specifically, stainless steel), while the elastic sleeve 67 and operation ring 69 are made of corrosion-resistant synthetic resin (fluororesin). This prevents the sterilization gas flowing through the flow path F from becoming a cause of corrosion of the first joint 60.

[0060] Hereinafter, the flow of assembling the piping section 43 will be described with reference to Fig. 6 and Fig. 9. When assembling the piping section 43, first, the first piping member 51A (see Fig. 6) is attached to the first joint 60, and the first joint 60 is fixed to the bracket 34. Next, the second piping member 51B is attached to the second joint 80 outside the arm 31. Specifically, the mounting portion 83 of the second joint 80 is inserted into the second piping member 51B with the nut 91 inserted into the second piping member 51B. Specifically, the second joint 80 is pushed in until the tip of the second piping member 51B abuts against the side surface of the enlarged diameter portion 82. After that, the nut 91 is tightened using a tool to fix the second joint 80 and the second piping member 51B. After the second joint 80 and the second piping member 51B are fixed, the second joint 80 (insertion portion 84) is inserted into the insertion hole 65 of the first joint 60. By pushing the second joint 80 into a position where the tip of the insertion portion 84 abuts against the stopper 66, the first joint 60 and the second joint 80 are sealed between the outer peripheral surface 84b of the insertion portion 84 and the inner peripheral surface 65a of the insertion hole 65 by the elastic sleeve 67, and the lock claw 68 is caught in the groove portion 89 of the insertion portion 84, thereby restricting separation of the first joint 60 and the second joint 80. As a result, the first piping member 51A and the second piping member 51B are connected to each other as shown in FIG. 6.

[0061] When the connection needs to be released for maintenance or the like, the restriction on separation between the first joint 60 and the second joint 80 is released by pushing the operation ring 69 of the first joint 60 into the insertion hole 65 (see FIG. 8(b)). With the operation ring 69 pushed in, the second joint 80 is pulled out of the insertion hole 65, whereby the connection between the first piping member 51A and the second piping member 51B is released.

[0062] According to the embodiment described above in detail, the following excellent effects can be expected.

[0063] According to the configuration shown in this embodiment, the piping section 43 (piping members 51 and piping joints 55) can be sterilized (decontaminated) by sucking sterilizing gas from the suction pad 42 while the piping section 43 is attached to the arm 31. In other words, there is no need to detach the piping section 43 every time a sterilization operation is performed, and even if sterilization operations are performed more frequently to strengthen hygiene control, an increase in the workload due to the sterilization operation can be suitably suppressed. In addition, since it is possible to suppress leakage of the sterilizing gas used in the sterilization operation into the arm 31, the inconvenience of corrosion of other robot parts in the arm 31 by the sterilizing gas is unlikely to occur.

[0064] With the second piping member 51B attached to the second joint 80, the second joint 80 (insertion portion 84) can be inserted into the insertion hole 65 of the first joint 60 to connect the first piping member 51A and the second piping member 51B. Simplifying the work within the arm 31 in this way is preferable in terms of reducing the likelihood of operational errors during the work and improving work efficiency.

[0065] In this embodiment, the inner peripheral surface 65a of the insertion hole 65 and the outer peripheral surface 84b of the insertion portion 84 are both circular, and it is not necessary to align the phases of the first joint 60 and the second joint 80 when inserting the second joint 80 into the first joint 60. This is preferable for facilitating the connection work of both joints 60, 80. In addition, the groove portion 89 into which the lock claw 68 is hooked is annular, and it is possible to rotate the second joint 80 about the central axis lines CL1, CL2 while maintaining the joints 60, 80 in a connected state. With this configuration, if it is confirmed that the second piping member 51B has been twisted after the joints 60, 80 are connected, it is possible to easily eliminate or alleviate the twisting of the second piping member 51B by rotating the second joint 80 together with the second piping member 51B.

[0066] The opening 33a formed in the arm 31 extends in the longitudinal direction of the arm 31, and the first joint 60 is fixed so that the central axis CL1 of the insertion hole 65 faces the longitudinal direction and the inlet portion 65c of the insertion hole 65 faces the center of the opening 33a. With this configuration, it becomes easy to ensure a path when inserting and removing the second joint 80 into and from the insertion hole 65 when connecting / disconnecting the first piping member 51A and the second piping member 51B. In particular, since the first joint 60 is fixed so as to be located around one short side portion of the opening 33a, it becomes even easier to ensure the above-mentioned path.

[0067] The second joint 80 and the second piping member 51B are sealed between the outer peripheral surface 83b of the second joint 80 (attachment portion 83) and the inner peripheral surface 51a of the second piping member 51B, preventing the sterilization gas from coming into contact with the portion of the second piping member 51B that is less resistant to corrosion (the outer peripheral surface 51b). This makes it possible to prevent corrosion on the outer peripheral surface 51b side. This is preferable in preventing the seal of the second piping member 51B from becoming weak due to the corrosion.

[0068] Both the first joint 60 and the second joint 80 have corrosion resistance. Therefore, even if sterilization gas enters the boundary portion BP1 between the inner peripheral surface 65a of the first joint 60 (insertion hole 65) and the outer peripheral surface 84b of the second joint 80 (insertion portion 84), corrosion of the first joint and the second joint caused by the sterilization gas is avoided. Avoiding corrosion of the inner peripheral surface 65a and the outer peripheral surface 84b is preferable in terms of preventing the seal from becoming weak due to the corrosion.

[0069] The attachment work of the second piping member 51B to the second joint 80 does not need to be performed in a narrow space inside the arm 31, but can be performed in a wide space outside the arm 31. Therefore, restrictions on the use of fixtures and tools for fixing the second piping member 51B to the second joint 80 can be alleviated. This is preferable in terms of properly fixing the second piping member 51B and suppressing leakage of sterilization gas from the boundary portion BP2 between the second piping member 51B and the second joint 80.

[0070] A configuration in which both joints 60, 80 can be connected by inserting the second joint 80 into the insertion hole 65 of the first joint 60 is preferable in terms of reducing the workload of the user. Here, when performing the insertion work in a narrow space, there is a possibility that the second joint 80 will be forcibly inserted at a slightly misaligned angle. In contrast, since the first joint 60 and the second joint 80 are formed of a material (stainless steel) having corrosion resistance, even if the surfaces (the inner peripheral surface 65a and the outer peripheral surface 84b) are slightly damaged due to the forcible insertion, it is possible to prevent this from becoming a cause of corrosion.

[0071] In the second joint 80, a portion (insertion portion 84) inserted into the insertion hole 65 of the first joint 60 and a portion (mounting portion 83) to which the second piping member 51B is attached are aligned in the direction of the central axis CL2, preventing the first joint 60, the second joint 80, and the second piping member 51B from overlapping in layers at the connection point of both joints 60, 80. This is preferable in terms of preventing the piping section 43 from becoming extremely thick at the connection point of the joints 60, 80 and enabling the piping section 43 to coexist with other robot parts, etc. within the arm 31.

[0072] <Other embodiments> The present invention is not limited to the above-described embodiment, and may be implemented as follows. Each of the following configurations may be applied individually to the above-described embodiment, or may be applied in combination with some or all of the following configurations to the above-described embodiment.

[0073] In the above embodiment, the piping member 51 is coated with fluororesin assuming sterilization using hydrogen peroxide gas, but the type of coating is not limited to fluorine. The type of coating (e.g., acrylic silicone, acrylic urethane, etc.) may be changed depending on the fluid used for sterilization (e.g., sodium hypochlorite, chloroform, etc.). In other words, it is sufficient that the piping member 51 is composed of a first layer (base layer) having flexibility and a second layer (coating layer) having superior corrosion resistance compared to the first layer, and the material of each layer may be changed as appropriate.

[0074] In the above embodiment, the second piping member 51B is fixed (crimped) to the joint body 81 using the nut 91, but the specific configuration for fixing the second piping member 51B to the second joint 80 is arbitrary. For example, the second piping member 51B may be fixed to the joint body 81 using a band or a clamp.

[0075] In the above embodiment, both the first joint 60 and the second joint 80 have a straight structure, but at least one of the first joint 60 and the second joint 80 may have an L-shaped structure.

[0076] In the above embodiment, the first joint 60 and the second joint 80 are disposed such that the first joint 60 is located on the tip side (hand tip side) of the arm 31 and the second joint 80 is located on the base end side of the arm 31, but the positions of the first joint 60 and the second joint 80 may be interchanged. That is, the second joint 80 may be configured to be located on the tip side (hand tip side) of the arm 31 and the first joint 60 on the base end side of the arm 31.

[0077] In the above embodiment, the second joint 80 is connected to the first joint 60 fixed to the bracket 34 of the arm 31, but the present invention is not limited to this. It is also possible to connect the first joint 60 to the second joint 80 fixed to the bracket 34 of the arm 31. In such a configuration, it is preferable to modify the bracket 34 so that the second joint 80 is located near the short side of the base end of the arm 31, out of a pair of short sides in the opening 33a.

[0078] The structure for fixing the first joint 60 to the bracket 34 shown in the above embodiment is arbitrary. The first joint 60 may be fixed by fitting the joint body 61 of the first joint 60 into a fitting portion formed in the bracket 34, or the first joint 60 may be fixed using fasteners such as bolts and nuts.

[0079] In the above embodiment, a gap is generated between the enlarged diameter portion 82 of the second joint 80 and the operation ring 69, but it is also possible to eliminate the gap. However, if the enlarged diameter portion 82 and the operation ring 69 come into contact with each other due to dimensional errors or the like and the operation ring 69 is pushed, there is a concern that the separation restriction between the first joint 60 and the second joint 80 may become insufficient or the separation restriction may be released. Therefore, as shown in the above embodiment, there is a technical significance in providing a gap between the enlarged diameter portion 82 and the operation ring 69 to avoid contact between them. In addition, it is preferable to provide a gap between the enlarged diameter portion 82 and the operation ring 69 in order to facilitate the operation of the operation ring 69 when separating the first joint 60 and the second joint 80 as described above.

[0080] In the above embodiment, an industrial robot used in a factory is illustrated, but the present invention can also be applied to robots used in food manufacturing, medical facilities, etc.

[0081] <Inventions extracted from the above embodiments> The following describes the features of the inventions extracted from the above-mentioned embodiments, while indicating, as necessary, their effects, etc. In the following, for ease of understanding, the corresponding configurations in the above-mentioned embodiments are appropriately indicated in parentheses, but the present invention is not limited to the specific configurations indicated in parentheses.

[0082] Feature 1: A piping structure for a robot (piping section 43) that is applied to an industrial robot (robot 15) having an arm (arm 31) with a plurality of joints, and that forms a flow path (flow path F) in the arm that connects a suction section (suction pad 42) attached to a hand tip (e.g., flange section 28) of the arm to a suction pump (pump 44), The flow path is formed by a plurality of piping members (piping members 51A, 51B) and a piping joint (piping joint 55) that connects the piping members in a series. The plurality of piping members include a first piping member (first piping member 51A) and a second piping member (second piping member 51B), As the piping joint, a first joint (first joint 60) having a first body portion (joint body 61) that configures the flow path, and to which the first piping member is attached at one end of the first body portion in a flow direction of the flow path; a second joint (second joint 80) that has a cylindrical second body portion (joint body 81) that is inserted into an insertion hole (insertion hole 65) formed at the other end of the first body portion and that constitutes a part of the flow path together with the first joint; Including, The first and second fittings are corrosion-resistant to a sterilization fluid (sterilization gas) that flows through the flow path during sterilization of the piping structure for a robot, and the piping structure for a robot is configured so that, when the second main body part is inserted into the insertion hole of the first main body part, a seal is formed between the outer peripheral surface (outer peripheral surface 84b) of the portion of the second main body part that is inserted into the insertion hole (insertion part 84) and the inner peripheral surface (inner peripheral surface 65a) of the insertion hole, and separation of the first and second fittings is restricted.

[0083] According to the configuration shown in this feature, by inserting the second body part of the second joint into the insertion hole of the first joint, the first joint and the second joint are sealed between the inner circumferential surface of the insertion hole of the first body part and the outer circumferential surface of the second body part, and separation of both joints is restricted. In this way, simplifying the work of connecting the first piping member and the second piping member is preferable in terms of improving the work efficiency and suppressing the work error when performing the work (assembly work of the piping structure) in the limited space in the arm. In addition, the attachment work (advance preparation) of the second piping member to the second joint does not need to be performed in the narrow space in the arm, but can be performed in the wide space outside the arm. Therefore, the constraints on the use of fixtures and tools when attaching the second piping member to the second joint can be relaxed. This is preferable in terms of firmly fixing the second piping member and the second joint and suppressing the leakage of the sterilization fluid from the boundary part between the second piping member and the second joint.

[0084] Both the first joint and the second joint are corrosion resistant. Therefore, even if sterilization gas gets into the boundary between the inner circumferential surface of the first joint (insertion hole) and the outer circumferential surface of the second joint, corrosion of the first joint and the second joint caused by the sterilization gas can be avoided, and the seal of both joints can be prevented from being weakened due to the corrosion. With the above configuration, leakage of sterilization fluid into the arm can be suppressed, and other robot parts housed in the arm can be protected.

[0085] According to this characteristic configuration, sterilization (decontamination) of piping members, piping joints, etc. can be performed by sucking sterilizing fluid from the suction part while the piping members, etc. are attached to the arm. This contributes to facilitating sanitation management of industrial robots. Furthermore, since there is no need to detach piping members, etc. every time a sterilization operation is performed, an increase in the workload caused by increasing the frequency of sterilization operations to strengthen sanitation management can be suitably suppressed.

[0086] Feature 2: A piping structure for a robot (piping section 43) that is applied to an industrial robot (robot 15) having an arm (arm 31) formed with a plurality of joints, and that forms a flow path (flow path F) in the arm that connects a suction section (suction pad 42) attached to a hand tip (e.g., flange section 28) of the arm to a suction pump (pump 44), The flow path is formed by a plurality of piping members (piping members 51A, 51B) and a piping joint (piping joint 55) that connects the piping members in a series. The plurality of piping members include a first piping member (first piping member 51A) and a second piping member (second piping member 51B), As the piping joint, a first joint (first joint 60) having a first body portion (joint body 61) that configures the flow path, and to which the first piping member is attached at one end of the first body portion in a flow direction of the flow path; a second joint (second joint 80) that has a cylindrical second body portion (joint body 81) that is inserted into an insertion hole (insertion hole 65) formed at the other end of the first body portion and that constitutes a part of the flow path together with the first joint; Including, the first joint and the second joint are corrosion-resistant against a sterilization fluid (sterilization gas) flowing through the flow path during sterilization of the robot piping structure, and are configured such that, when the second body part is inserted into the insertion hole of the first body part, a seal is formed between an outer peripheral surface (outer peripheral surface 84b) of a portion (insertion part 84) of the second body part inserted into the insertion hole and an inner peripheral surface (inner peripheral surface 65a) of the insertion hole, and separation of the first joint and the second joint is restricted; The inner circumferential surface of the second piping member is configured to have a corrosion-resistant layer (coating layer 53) having higher corrosion resistance than a base layer (base layer 52) of the second piping member, The second joint is formed such that a part of the second body portion extends from the insertion hole in a state in which separation is restricted, and a mounting portion (mounting portion 83) to which a second piping member is attached is provided on the extending portion, A piping structure for a robot, in which the mounting portion of the second fitting is inserted into the second piping member, and the second fitting and the second piping member are sealed between the outer peripheral surface (outer peripheral surface 83b) of the mounting portion and the inner peripheral surface of the second piping member.

[0087] According to the configuration shown in this feature, by inserting the second body part of the second joint into the insertion hole of the first joint, the first joint and the second joint are sealed between the inner circumferential surface of the insertion hole of the first body part and the outer circumferential surface of the second body part, and separation of both joints is restricted. In this way, simplifying the work of connecting the first piping member and the second piping member is preferable in terms of improving the work efficiency and suppressing the work error when performing the work (assembly work of the piping structure) in the limited space in the arm. In addition, the attachment work (advance preparation) of the second piping member to the second joint does not need to be performed in the narrow space in the arm, but can be performed in the wide space outside the arm. Therefore, the constraints on the use of fixtures and tools when attaching the second piping member to the second joint can be relaxed. This is preferable in terms of firmly fixing the second piping member and the second joint and suppressing the leakage of the sterilization fluid from the boundary part between the second piping member and the second joint.

[0088] The second piping member has a multi-layer structure with a corrosion-resistant layer provided on the inner peripheral surface side. This configuration allows for greater freedom in the material of the base layer of the second piping member while providing corrosion resistance. This is preferable in terms of optimizing the elasticity and flexibility of the second piping member, easing restrictions on piping arrangement, and improving the durability of the second piping member. In addition, the second joint and the second piping member are sealed between the outer peripheral surface of the second main body and the inner peripheral surface of the second piping member. This suppresses corrosion of the portion (outer peripheral surface) of the second piping member that has low corrosion resistance, and suppresses the seal of the second piping member from being weakened due to the corrosion. In addition, both the first joint and the second joint have corrosion resistance. Therefore, even if sterilization gas enters the boundary between the inner peripheral surface of the first joint (insertion hole) and the outer peripheral surface of the second joint, corrosion of the first joint and the second joint due to the corrosion can be avoided, and the seal of both joints can be suppressed from being weakened due to the corrosion. The above-described configuration can prevent leakage of sterilizing fluid into the arm, thereby contributing to the protection of other robot parts housed within the arm.

[0089] According to this characteristic configuration, sterilization (decontamination) of piping members, piping joints, etc. can be performed by sucking sterilizing fluid from the suction part while the piping members, etc. are attached to the arm. This contributes to facilitating sanitation management of industrial robots. Furthermore, since there is no need to detach piping members, etc. every time a sterilization operation is performed, an increase in the workload caused by increasing the frequency of sterilization operations to strengthen sanitation management can be suitably suppressed.

[0090] Feature 3. The piping structure for a robot according to Feature 2, wherein the first joint and the second joint are formed from a material that is corrosion-resistant to the fluid, and the corrosion-resistant layer of the second piping member is formed by coating.

[0091] It is preferable to configure the first joint (first body portion) so that the two joints can be connected by inserting the second joint into the insertion hole of the first joint, in order to reduce the user's workload. Here, when performing the insertion work in a narrow space, the second joint may be forcibly inserted at a slightly misaligned angle. In contrast, if the first joint and the second joint are made of a material having corrosion resistance, even if the surface (inner circumferential surface or outer circumferential surface) is slightly damaged due to the forcible insertion, it is possible to prevent this from becoming a cause of corrosion. In addition, since the second piping member is given corrosion resistance by coating, it is possible to reduce restrictions on the material of the base portion of the second piping member. In other words, assuming that the second piping member is accommodated in the arm, it is possible to optimize the elasticity and flexibility of the second piping member, and it is possible to reduce the occurrence of inconveniences such as difficulty in handling the second piping member in ensuring corrosion resistance.

[0092] When hydrogen peroxide is used as the sterilizing fluid, for example, the second piping member may have a multi-layer structure with a polyurethane layer as the base layer and a fluorine layer as the corrosion-resistant layer.

[0093] Feature 4. A piping structure for a robot according to Feature 2 or Feature 3, characterized in that the portion of the second body portion of the second fitting that is inserted into the insertion hole of the first fitting and the mounting portion to which the second piping member is attached are aligned in the axial direction of the second body portion.

[0094] According to this characteristic configuration, it is possible to prevent the first joint, the second joint, and the second piping member from overlapping in layers at the connection point between the two joints. This is preferable in terms of preventing the piping structure from becoming extremely thick at the connection point and ensuring the coexistence of the piping structure with other robot parts, etc. within the arm.

[0095] Feature 5: A protrusion (expanded diameter portion 82) is provided at the middle portion of the second body portion, protruding in a direction intersecting with the central axis of the second body portion; The second fitting has a fastener (nut 91) that engages with a threaded portion (main body side threaded portion 86) formed on the outer peripheral surface of the protrusion, thereby clamping the second piping member attached to the mounting portion between the mounting portion and the second fitting. A piping structure for a robot as described in any one of Features 2 to 4.

[0096] The posture of the arm of the industrial robot shown in feature 2 and the like may change in various ways. For this reason, it is preferable to firmly fix the second piping member to the second joint in order to prevent the second piping member from falling off. Here, if the second piping member is sandwiched between the mounting portion of the second joint and the fixing device as shown in this feature, the second piping member can be suitably prevented from falling off. However, if the second piping member is simply fixed using the fixing device, the second piping member may be twisted (torsion stress) due to the tightening of the fixing device. There is a concern that the torsion stress remaining in the second piping member may be a factor that accelerates the deterioration of the second piping member or a factor that reduces the suction function. In this regard, by combining with the configuration shown in feature 2 and the like, even when the second piping member is fixed to the second joint using the fixing device, the work can be performed with both joints separated. Therefore, the torsion stress remaining in the second piping member can be minimized. Furthermore, even when a tool is used to tighten the fixture, there is no need to take measures such as ensuring a gap for the tool to be inserted within the arm, which is also preferable in terms of coexistence with other robot parts (peripheral parts) within the arm.

[0097] Feature 6: The first joint has a restricting portion (lock claw 68) switchable between a restricting state that restricts separation of the first joint and the second joint and a non-restricting state that does not restrict the separation, and an operating portion (operating ring 69) that is displaceable in the axial direction of the insertion hole and is arranged to protrude from the insertion hole, and is configured such that the restricting portion is switched from the restricting state to the non-restricting state when a user presses the operating portion toward the insertion hole; The piping structure for a robot described in Feature 5, wherein the first joint and the second joint are formed so that the operation portion is not in contact with the protrusion and the fixing device when separation is restricted by the restricting portion.

[0098] As shown in this feature, making the first joint and the second joint separable by operating the operating part is preferable in terms of facilitating the separation operation. Here, the protrusion and the fastener of the second joint are configured so as to be out of contact with the operating part, i.e., so that a gap is formed between the operating part and the protrusion, etc. This configuration prevents the protrusion and the fastener from interfering with the operation when a finger is hooked on the operating part and pushed toward the insertion hole, which contributes to facilitating the separation operation of the first joint and the second joint.

[0099] Feature 7: The first joint has a restricting portion (lock claw 68) switchable between a restricting state in which separation of the first joint and the second joint is restricted and a non-restricting state in which separation is not restricted, and an operating portion (operating ring 69) that is displaceable in the axial direction of the insertion hole and is disposed so as to protrude from the insertion hole, and is configured such that the restricting portion is switched from the restricting state to the non-restricting state when a user pushes the operating portion toward the insertion hole; The piping structure for a robot according to feature 5 or 6, wherein an offset amount (distance dimensions L2, L3) of the outer peripheral surface of the protrusion and the outer peripheral surface of the fixing device relative to the central axis of the second joint is smaller than an offset amount (distance dimension L1) of the outer peripheral surface of the operating part relative to the central axis of the insertion hole.

[0100] As shown in this feature, making it possible to separate the first joint from the second joint by operating the operating part is preferable in terms of facilitating the separation operation. Here, the offset amount of the outer circumferential surface of the protrusion and the outer circumferential surface of the nut relative to the central axis of the second joint is smaller than the offset amount of the outer circumferential surface of the operating part relative to the central axis of the insertion hole. With this configuration, it is possible to prevent the protrusion and the fixing tool from interfering with the operation when a finger is hooked on the operating part and pushed toward the insertion hole, which contributes to facilitating the separation operation of the first joint and the second joint.

[0101] Feature 8. The inner circumferential surface of the insertion hole and the outer circumferential surface of the second main body portion are both circular, A second joint side locking portion (groove portion 89) is formed on the outer circumferential surface of the second main body portion and has an annular shape centered on the central axis of the second main body portion. The piping structure for a robot according to any one of Features 2 to 7, wherein the first fitting has a first fitting side engaging portion (lock claw 68) that restricts the separation by engaging with the second fitting side engaging portion.

[0102] According to this characteristic configuration, when inserting the second joint into the insertion hole of the first joint, it is not necessary to align the phases of the first and second joints, which is preferable in terms of preventing torsion (stress) from remaining in the connected piping members.

[0103] Feature 9. A piping structure for a robot described in any one of Features 1 to 8, wherein the second fitting side locking portion is an annular recess formed on the outer peripheral surface of the second main body portion, and the first fitting side locking portion is a claw portion that locks into the groove portion.

[0104] As shown in this feature, if the second joint side locking portion is configured to be concave, the gap between the inner circumferential surface of the insertion hole and the outer circumferential surface of the second main body portion can be minimized. This is preferable in terms of preventing the joint from becoming thick at the connection point and ensuring compatibility with surrounding parts within the arm.

[0105] The technical ideas shown in Features 3 to 9 above may be applied to Feature 1.

[0106] Feature 10. A piping structure for a robot according to any one of features 1 to 9, The arm is provided with an opening (opening 33a) extending in the longitudinal direction of the arm, a lid portion (cover 33b) covering the opening, and a fixing portion (bracket 34) that fixes the first joint so that the central axis of the insertion hole faces the longitudinal direction and the inlet portion (inlet portion 65c) of the insertion hole faces the center of the opening.

[0107] According to this characteristic configuration, when connecting / disconnecting the piping members for maintenance or the like, the opening of the arm can be opened to access the piping members. The opening extends in the longitudinal direction of the arm, and the first joint is fixed such that the central axis of the insertion hole faces the longitudinal direction and the inlet portion of the insertion hole faces the center of the opening. With this configuration, it is easy to ensure a path for inserting and removing the second joint into and from the insertion hole when connecting / disconnecting the first piping member and the second piping member.

[0108] Feature 11. The opening has a substantially rectangular shape, The industrial robot according to feature 10, wherein the fixing portion is configured to fix the first joint so as to be positioned around one of the short side portions of the opening.

[0109] As shown in this feature, if the first joint is configured to be fixed so as to be positioned around the short side portion of 1, it becomes even easier to ensure the working space as shown in feature 10.

[0110] Feature 12. The device has an arm (arm 31) with multiple joints formed therein, An industrial robot (robot 15) in which a suction part (suction pad 42) for suctioning a work (work W) is attached to a tip of the arm, and a robot piping structure (piping part 43) for forming a flow path (flow path F) connecting the suction part and a suction pump (pump 44) is disposed inside the arm, The robot piping structure includes a first piping member (first piping member 51A) and a second piping member (second piping member 51B), and a piping joint (piping joint 55) that connects the piping members in a series, As the piping joint, a first joint (first joint 60) having a first body portion (joint body 61) that configures the flow path, and having the first piping member attached to one end of the first body portion in a flow direction of the flow path; a second joint (second joint 80) that has a cylindrical second body portion (joint body 81) that is inserted into an insertion hole (insertion hole 65) formed at the other end of the first body portion and that constitutes a part of the flow path together with the first joint; Including, the first joint and the second joint are corrosion-resistant against a sterilization fluid (sterilization gas) flowing through the flow path during sterilization of the robot piping structure, and are configured such that, when the second body part is inserted into the insertion hole of the first body part, a seal is formed between an outer peripheral surface (outer peripheral surface 84b) of a portion (insertion part 84) of the second body part inserted into the insertion hole and an inner peripheral surface (inner peripheral surface 65a) of the insertion hole, and separation of the first joint and the second joint is restricted; The inner circumferential surface of the second piping member is configured to have a corrosion-resistant layer (coating layer 53) having higher corrosion resistance than a base layer (base layer 52) of the second piping member, The second joint is formed such that a part of the second body portion extends from the insertion hole in a state in which separation is restricted, and a mounting portion (mounting portion 83) to which a second piping member is attached is provided on the extending portion, An industrial robot in which the mounting portion of the second fitting is inserted into the second piping member, and the second fitting and the second piping member are sealed between an outer peripheral surface (outer peripheral surface 83b) of the mounting portion and an inner peripheral surface of the second piping member.

[0111] This configuration can contribute to facilitating sanitary management of industrial robots and protecting other robot parts housed within the arm. [Explanation of symbols]

[0112] 10...robot system, 15...robot as industrial robot, 31...arm, 32...housing, 33a...opening, 33b...cover, 34...bracket, 41...suction device, 42...suction pad as suction section, 43...piping section as piping structure, 44...pump, 51A...first piping member, 51B...second piping member, 52...base layer, 53...coating layer as corrosion-resistant layer, 55...piping joint, 60...first joint, 61... Fitting body as first main body portion, 65...insertion hole, 67...elastic sleeve, 68...locking claw as first fitting side engaging portion, 69...operating ring as operating portion, 80...second fitting, 81...fitting body as second main body portion, 82...expansion portion, 83...mounting portion, 84...insertion portion, 89...groove portion as second fitting side engaging portion, 91...nut, BP1, BP2...boundary portion, CL1, CL2...central axis, F...flow path, L1-L3...distance dimension, W...work.

Claims

1. A piping structure for a robot, which is applied to an industrial robot having an arm formed with a plurality of joints, and forms a flow path in the arm connecting a suction part attached to a tip of the arm and a suction pump, a plurality of piping members constituting the flow path and a piping joint connecting the piping members in a series; The plurality of piping members include a first piping member and a second piping member, As the piping joint, a first joint having a first body portion that configures the flow path, the first piping member being attached to one end of the first body portion in a flow direction of the flow path; a second joint having a cylindrical second body portion inserted into an insertion hole formed at the other end of the first body portion, the second joint constituting a part of the flow path together with the first joint; Including, the first joint and the second joint are corrosion-resistant to a sterilization fluid flowing through the flow path during sterilization of the robot piping structure, and are configured such that, when the second main body part is inserted into the insertion hole of the first main body part, a seal is formed between an outer peripheral surface of a portion of the second main body part inserted into the insertion hole and an inner peripheral surface of the insertion hole, and separation of the first joint and the second joint is restricted, The inner circumferential surface of the second piping member is configured to be a corrosion-resistant layer having higher corrosion resistance than a base layer of the second piping member, the second joint is formed such that a part of the second body portion extends from the insertion hole in a state in which separation is restricted, and an attachment portion to which a second piping member is attached is provided on the extending part, A piping structure for a robot, wherein the mounting portion of the second fitting is inserted into the second piping member, and the second fitting and the second piping member are sealed between an outer peripheral surface of the mounting portion and an inner peripheral surface of the second piping member.

2. 2. The piping structure for a robot according to claim 1, wherein the first joint and the second joint are formed from a material that is corrosion-resistant to the fluid, and the corrosion-resistant layer of the second piping member is formed by coating.

3. An inner circumferential surface of the insertion hole and an outer circumferential surface of the second main body portion are both circular, An annular groove is formed on an outer circumferential surface of the second body portion, the groove being centered on a central axis of the second body portion, 3. The piping structure for a robot according to claim 1, wherein the first joint has a claw portion that is engaged with the groove portion to restrict the separation.

4. A protrusion is provided at an intermediate portion of the second main body portion, the protrusion protruding in a direction intersecting with a central axis of the second main body portion, the second joint has a fastener that engages with a threaded portion formed on an outer circumferential surface of the protruding portion to fix the second piping member attached to the mounting portion so as to sandwich the second piping member between the mounting portion and the fastener, The first joint has a restricting portion switchable between a restricting state that restricts separation of the first joint and the second joint and a non-restricting state that does not restrict the separation, and an operating portion that is displaceable in the axial direction of the insertion hole and is arranged to protrude from the insertion hole, and is configured such that the restricting portion is switched from the restricting state to the non-restricting state by a user pushing the operating portion toward the insertion hole, 3. The piping structure for a robot according to claim 1, wherein the first joint and the second joint are formed so that when separation is restricted by the restricting portion, the operating portion is not in contact with the protrusion and the fixing device.

5. An arm having a plurality of joints formed therein, An industrial robot in which a suction unit that sucks a workpiece is attached to a tip of the arm, and a robot piping structure that forms a flow path connecting the suction unit and a suction pump is disposed inside the arm, The robot piping structure includes a first piping member, a second piping member, and a piping joint that connects the piping members in a series, As the piping joint, a first joint having a first body portion that configures the flow path, the first piping member being attached to one end of the first body portion in a flow direction of the flow path; a second joint having a cylindrical second body portion inserted into an insertion hole formed at the other end of the first body portion, the second joint constituting a part of the flow path together with the first joint; Including, the first joint and the second joint are corrosion-resistant to a sterilization fluid flowing through the flow path during sterilization of the robot piping structure, and are configured such that, when the second main body part is inserted into the insertion hole of the first main body part, a seal is formed between an outer peripheral surface of a portion of the second main body part inserted into the insertion hole and an inner peripheral surface of the insertion hole, and separation of the first joint and the second joint is restricted, The inner circumferential surface of the second piping member is configured to be a corrosion-resistant layer having higher corrosion resistance than a base layer of the second piping member, the second joint is formed such that a part of the second body portion extends from the insertion hole in a state in which separation is restricted, and an attachment portion to which a second piping member is attached is provided on the extending part, An industrial robot wherein the mounting portion of the second fitting is inserted into the second piping member, and the second fitting and the second piping member are sealed between an outer peripheral surface of the mounting portion and an inner peripheral surface of the second piping member.

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