Open / close gripper

Abstract

To provide an opening / closing gripper that can be adjusted forward / backward in its orientation in a conveyance direction with a simple structure.SOLUTION: An opening / closing gripper comprises: a pair of gripper pieces 18A and 18B arranged so as to be rotatable about the same axis; a biasing member 40 that biases the gripper pieces 18A and 18B in a direction approaching each other; cam followers 34A and 34B respectively connected to the gripper pieces 18A and 18B; a first cam 38 that engages the cam follower 34A to operate the cam follower 34A; and a second cam that engages the cam follower 34B to operate the cam follower 34B. When the gripper pieces 18A and 18B are opened / closed, both the cam followers 34A and 34B are operated. When the gripper pieces 18A and 18B are oscillated, only the cam follower 34A is operated.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to an openable / closable gripper that grips and conveys containers. [Background Art]

[0002] In systems that perform processing such as filling and capping while conveying containers, a container processing system is known in which the containers are conveyed while alternately gripping the upper and lower sides of the flanges of the containers by grippers provided on each rotating wheel. An openable / closable gripper using an opening / closing mechanism such as a cam and a cam follower is employed for the gripper of the rotating wheel that grips above the flange, while a leaf spring type gripper that is constantly biased in the closing direction by a spring is employed for the gripper of the rotating wheel that grips below the flange. In addition, in such a container processing system, for the purpose of changing the pitch of containers during conveyance, a configuration has also been proposed in which the leaf spring type gripper is made rotatable and the leaf spring type gripper is swung using a mechanism such as a cam or a gear (see Patent Documents 1 and 2). [Prior Art Literature] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent No. 4026861 [Patent Document 2] Japanese Patent No. 6306409 [Summary of the Invention] [Problems to be Solved by the Invention]

[0004] However, since swingable grippers are limited to leaf spring type grippers in Cited Documents 1 and 2 and the like, an openable / closable gripper cannot be swung by a rotating wheel provided with openable / closable grippers, and a rotating wheel provided with leaf spring type grippers has to be arranged downstream to swing the leaf spring type grippers. As described above, the rotating wheel for swinging the gripper is limited, which restricts the degree of freedom in system design.

[0005] The present invention aims to provide an openable / closable gripper that allows the orientation of the gripper to be moved forward or backward with respect to the conveying direction with a simple configuration. [Means for solving the problem]

[0006] The open / close gripper of the present invention comprises a pair of grip pieces rotatably arranged on the same axis, a biasing means for biasing the grip pieces toward each other, a first cam follower and a second cam follower connected to each of the pair of grip pieces, a first cam that engages with the first cam follower to actuate the first cam follower, and a second cam that engages with the second cam follower to actuate the second cam follower, wherein both the first and second cam followers are actuated when opening and closing the pair of grip pieces, and only one of the first or second cam followers is actuated when swinging the pair of grip pieces. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide an openable and closable gripper that allows the orientation of the gripper to be moved forward and backward with respect to the conveying direction with a simple configuration. [Brief explanation of the drawing]

[0008] [Figure 1] This is a plan view showing the arrangement of some components of a container processing system employing an open / close gripper, which is one embodiment of the present invention. [Figure 2] This is a view from the direction of transport of a container gripped by an open / close gripper in the external sterilization area. [Figure 3] This is a view from the direction of transport of a container gripped by an open / close gripper in the internal sterilization area. [Figure 4] This is a perspective view showing the configuration of the retractable gripper for the sterilization wheel that grips the container. [Figure 5] This is a longitudinal cross-sectional view of the area around the open / close gripper that holds the container. [Figure 6] This is a plan view showing the configuration of the gripper that is released at the handover position. [Figure 7] This is a plan view showing the configuration of the gripper in Figure 6, conveniently separated into left and right sections. [Figure 8] This is a plan view showing the posture of the gripper at five points as it moves along the first cam. [Modes for carrying out the invention]

[0009] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Figure 1 is a plan view showing the arrangement of some components of a container processing system employing an open / close gripper, which is one embodiment of the present invention.

[0010] The container processing system 10 of this embodiment is a system that performs, for example, liquid filling and capping processes on a container V being transported. The container V is, for example, a bottle equipped with a flange Vf at its neck (see Figure 2), and is transported by gripping the upper or lower part of the flange Vf with grippers provided along the outer circumference of a rotating wheel. The container V is passed between rotating wheels, and during the transfer, the upper and lower positions of the flange Vf gripped by the grippers are alternately switched. The lower side of the flange Vf is gripped by a leaf spring type gripper, and the upper side of the flange Vf is gripped by an open / close type gripper 18.

[0011] The container processing system 10 includes, for example, a sterilization wheel 14 for sterilizing containers V. As shown in Figure 1, containers V are passed from the supply wheel 12 to the sterilization wheel 14, and after being sterilized as they move along the outer circumference, they are passed to the discharge wheel 16. In the sterilization wheel 14 of this embodiment, the outside of the container is sterilized in the outer surface sterilization area A1 (external sterilization), and the inside of the container is sterilized in the inner surface sterilization area A2 (internal sterilization). The order and number of times external and internal sterilization are performed are arbitrary, but in the sterilization wheel 14 of this embodiment, external sterilization is performed once, followed by internal sterilization twice.

[0012] Figure 2 is a view from the direction of transport in the external sterilization area A1 of container V, which is gripped by the open / close gripper 18. Figure 2 shows the arrangement of the open / close gripper 18 that grips container V, the hood 20 (cross-sectional view), and the sterilization gas supply pipe 22 that sprays sterilization gas such as hydrogen peroxide. The hood 20 is positioned on the outer circumference of the sterilization wheel 14, extending from the external sterilization area A1 to two internal sterilization areas A2.

[0013] In the external sterilization area A1, the open / close gripper 18 is positioned radially outward from the sterilization wheel 14, and the container V is gripped by the upper part of its flange Vf by the open / close gripper 18 and transported along the outer circumference of the sterilization wheel 14. A sterilization gas supply pipe 22, bent in a roughly C shape, is positioned in the external sterilization area A1, and the container V, gripped by the open / close gripper 18, is transported inside the C-shaped sterilization gas supply pipe 22. Inside the sterilization gas supply pipe 22, there are multiple external sterilization nozzles 22A to 22E that spray sterilization gas toward the transported container V. The external sterilization nozzles 22A to 22E are positioned so that the entire outer surface of the container V being transported inside the sterilization supply pipe 22 is exposed to the sterilization gas.

[0014] Furthermore, in the external sterilization area A1, a hood 20 with a roughly J-shaped cross-section is positioned along the transport path, surrounding the sterilization gas supply pipe 22 from the outside, below, and inside. This prevents the sterilization gas sprayed from the external sterilization nozzles 22A to 22E toward the container V from diffusing into the surroundings.

[0015] Figure 3 is a view from the direction of transport of a container V held by an openable / closable gripper 18 in the internal sterilization area A2, showing the arrangement of the openable / closable gripper 18 that grips the container V, the hood 20 (cross-sectional view), and the internal sterilization nozzle 24 that sprays a sterilization gas such as hydrogen peroxide gas into the container from the mouth Vm of the container V.

[0016] The inner surface sterilization nozzle 24 is arranged so as to be located substantially directly above the center of the mouth portion Vm of the container V being conveyed, and sterilization gas is injected from above through the mouth portion Vm into the container V being conveyed in an upright state in the inner surface sterilization area A2. The container V being conveyed is surrounded on three sides, i.e., the outer side, the lower side, and the inner side, by the hood 20.

[0017] Fig. 4 is a perspective view showing the configuration of the opening-and-closing gripper 18 of the sterilization wheel 14 that grips the container V, and Fig. 5 is a longitudinal cross-sectional view of the periphery of the opening-and-closing gripper 18 that grips the container V.

[0018] The injection of sterilization gas into the container V by the inner surface sterilization nozzle 24 in the inner surface sterilization area A2 can be performed only while the mouth portion Vm of the container V is located below the inner surface sterilization nozzle 24. Therefore, when the rotation speed of the sterilization wheel 14 is increased to raise the processing speed of containers V, the time during which the mouth portion Vm of the container V passes below the inner surface sterilization nozzle 24 is shortened, making it impossible to supply a sufficient amount of sterilization gas into the container V. In the present embodiment, by swinging the opening-and-closing gripper 18 that grips the container V, the time during which the mouth portion Vm of the conveyed container V is located below the inner surface sterilization nozzle 24 is extended, so that a sufficient amount of sterilization gas can be supplied to the container V. Specifically, the opening-and-closing gripper 18 is advanced on the upstream side of the inner surface sterilization nozzle 24, and retracted on the downstream side of the inner surface sterilization nozzle 24.

[0019] As shown in Fig. 4, the opening-and-closing gripper 18 includes a pair of gripper pieces 18A and 18B. The base portions of the gripper pieces 18A and 18B are stacked one above the other and are coaxially rotatable around the same rotation shaft 26. The distal end sides of the gripper pieces 18A and 18B for gripping the neck portion of the container V are arranged alternately at the same height.

[0020] The rotation shaft 26 has a double structure including a cylindrical shaft 26A and a central shaft 26B rotatably fitted into the cylindrical shaft 26A. The cylindrical shaft 26A is pivotally supported at two upper and lower positions by support members 28A and 28B arranged vertically. The support members 28A and 28B are connected by a connecting member 30, and rotate integrally with the rotating body of the sterilization wheel 14.

[0021] The upper and lower ends of the central shaft 26B protrude from the upper and lower ends of the cylindrical shaft 26A. A lever 32B is attached to the lower end of the central shaft 26B, and the base end of a gripper piece 18B is attached to the upper end. On the other hand, a lever 32A is attached to the central part of the cylindrical shaft 26A, and the base end of a gripper piece 18A is attached to the upper end. In other words, the gripper piece 18B is positioned on top of the gripper piece 18A.

[0022] A cam follower 34A and one end of a biasing member 36, such as a coil spring, are attached to the tip of the lever 32A. The other end of the biasing member 36 is attached to the support member 28A, biasing the lever 32A, i.e., the cam follower 34A, toward the radially inward direction of the sterilization wheel 14. Inside the cam follower 34A, a first cam 38 is arranged in an annular shape around the entire circumference of the sterilization wheel 14, against which the cam follower 34A is pressed by the biasing force of the biasing member 36. As a result, as the sterilization wheel 14 rotates, the cam follower 34A moves along the first cam 38, and the gripper piece 18A, which is linked to the cam follower 34A, swings about the rotation axis 26.

[0023] Furthermore, the gripper pieces 18A and 18B are connected by a biasing member (biasing means) 40 such as a coil spring at the tip side of the rotating shaft 26, and the biasing member 40 biases the gripper pieces 18A and 18B in the direction of closing them together.

[0024] On the other hand, the cam follower 34B, which is linked to the gripper piece 18B, engages with the second cam 42, which is provided only at the position where the container V is transferred between the supply wheel 12 and the discharge wheel 16, and is free in other sections. Therefore, except at the transfer position where the cam follower 34B engages with the second cam 42, the gripper piece 18B swings integrally with the gripper piece 18A around the rotation axis 26 due to the biasing force of the biasing member 40.

[0025] Figure 6 shows the open / close gripper 18 when it is opened at the transfer position, the engagement state of the cam follower 34A and the first cam 38, and the engagement state of the cam follower 34B and the second cam 42. In addition, Figure 7 shows the engagement state of the cam follower 34B and the second cam 42, which is partially visible in the plan view of Figure 6 because they overlap vertically, by conveniently separating the configuration of the gripper piece 18A, cam follower 34A, and first cam 38 from the configuration of the gripper piece 18B, cam follower 34B, and second cam 42 into left and right sides.

[0026] As shown in Figures 6 and 7, at the transfer position, the cam follower 34A is pushed radially outward by the first cam 38 beyond the reference position (reference radius) of the first cam 38, and the gripper piece 18A is rotated forward in the container transport direction. On the other hand, the cam follower 34B is pushed radially inward by the second cam 42, and the gripper piece 18B is rotated backward in the container transport direction against the biasing force of the biasing member 40. As a result, the open / close gripper 18 is opened at the transfer position, allowing the container V to be transferred between the supply wheel 12 and the discharge wheel 16.

[0027] Next, referring to Figure 8, which is an enlarged plan view of the internal sterilization area A2, the swinging motion of the open / close type gripper 18 along the container transport direction in this embodiment will be described.

[0028] Outside of the transfer position and the internal sterilization area A2, the cam follower 34A is maintained in a reference position by the first cam 38, and the gripper piece 18A is maintained in a radial orientation. In these sections, the cam follower 34B is free, so the gripper piece 18B is pressed against the gripper piece 18A by the biasing force of the biasing member 40. As a result, the gripper piece 18B is maintained in the same orientation as the gripper piece 18A, along the radial direction of the sterilization wheel 14, and the open / close gripper 18 is maintained in a closed state. In other words, the orientation of the open / close gripper 18 is determined by the first cam 38 and the cam follower 34A.

[0029] Meanwhile, in the internal sterilization area A2, the gripper piece 18A is oscillated back and forth in the container transport direction due to the engagement of the cam follower 34A and the first cam 38. At this time, since the cam follower 34B is in a free state, the gripper piece 18B is pressed against the gripper piece 18A by the biasing member 40 (the open / close type gripper 18 is in a closed state) and oscillates integrally with the gripper piece 18A.

[0030] Figure 8 shows the five positions of the open / close gripper 18 as it moves along the first cam 38. Upstream of the first internal sterilization area A2, the first cam 38 is in a reference position, and the open / close gripper 18 is oriented radially toward the sterilization wheel 14. When the open / close gripper 18 reaches the first internal sterilization area A2, the cam follower 34A is pushed radially outward from its reference position by the first cam 38. This rotates the open / close gripper 18 forward in the transport direction, advancing the mouth Vm of the container V below the internal sterilization nozzle 24. Subsequently, in accordance with the rotation of the sterilization wheel 14, the cam follower 34A is pushed radially inward to its reference position, and the open / close gripper 18 is rotated backward until its orientation is radial. This maintains the position of the mouth Vm of the container V gripped by the open / close gripper 18 below the internal sterilization nozzle 24. As the sterilization wheel 14 rotates further, the cam follower 34A is pushed radially inward from its reference position, the open / close gripper 18 is rotated towards the rear in the conveying direction, and the mouth Vm of the container V gripped by the open / close gripper 18 is maintained below the passing internal sterilization nozzle 24.

[0031] When the retractable gripper 18 passes through the first internal sterilization area A2, the retractable gripper 18 is again moved forward and directed radially outward. When the retractable gripper 18 reaches the second internal sterilization area A2, as in the first internal sterilization area A2, the retractable gripper 18 is rotated forward so that the mouth Vm of the container V is moved forward below the internal sterilization nozzle 24, and then the retractable gripper 18 is rotated backward so that the mouth Vm is maintained below the internal sterilization nozzle 24 for a certain period of time.

[0032] As described above, according to this embodiment, even with an open / close type gripper, the orientation of the gripper can be moved back and forth relative to the conveying direction with a simple configuration. This expands the design flexibility even in conveying systems that alternately transfer containers using open / close type grippers and leaf spring type grippers.

[0033] In this embodiment, a sterilization wheel was used as an example, but this embodiment can be applied not only to sterilization wheels but also to other conveying wheels and conveying devices other than wheel types (for example, linear conveying devices) for the purpose of ensuring the dwell time of containers at a specific position without changing the conveying speed. In addition, in this embodiment, the first cam is placed on the inside and the second cam is placed on the outside, but it is also possible to configure the cam acting as the first cam to be placed on the outside and the cam acting as the second cam to be placed on the inside. In that case, the gripper piece 18A will rotate in accordance with the swinging of the gripper piece 18B. [Explanation of symbols]

[0034] 18. Open / Close Gripper 18A, 18B gripper piece 34A, 34B Cam Followers (1st and 2nd Cam Followers) 38 First Cam 40. Biasing member (biasing means) 42 Second Cam

Claims

[Claim 1] A pair of grip pieces rotatably positioned on the same axis, A biasing means for biasing the grip pieces toward each other, A first cam follower and a second cam follower are connected to each of the pair of grip pieces, A first cam that engages with the first cam follower to actuate the first cam follower, It comprises a second cam that engages with the second cam follower to actuate the second cam follower, When opening and closing the pair of grip pieces, both the first cam follower and the second cam follower are activated, When the pair of grip pieces is oscillated, only one of the first cam follower and the second cam follower is activated. A gripper with an opening and closing mechanism, characterized by its features.

Images