CN112429457A

CN112429457A - Conductive device and roller conveying device

Info

Publication number: CN112429457A
Application number: CN202010729931.0A
Authority: CN
Inventors: 广田雅治; 羽方满之
Original assignee: Screen Holdings Co Ltd
Current assignee: Screen Holdings Co Ltd
Priority date: 2019-08-26
Filing date: 2020-07-27
Publication date: 2021-03-02
Also published as: KR20210024977A; KR102418285B1; TW202109721A; TWI774033B; JP2021031240A; JP6997745B2

Abstract

The invention provides a structure which is easy to assemble in a conductive device and a roller conveying device which are installed on a roller shaft for the purpose of electric grounding. The conductive device of the present invention comprises: a housing (100) having an engagement portion (11) engaged with an end portion of the roller shaft; a shaft member (40) which is formed of a conductive material and protrudes from the inside of the housing to the outside through an opening provided in the housing; a bearing (50) which is provided in the housing and rotatably supports the shaft member relative to the housing; and conductive parts (20, 30) which elastically abut against the shaft member and electrically connect the shaft member and the housing. The housing includes: a main body (10) having an internal space capable of accommodating the bearing and the conductive part; and a cover (60) which is engaged with the main body to close the internal space, thereby sealing the bearing and the conductive portion in the internal space; the body portion and the lid portion are integrated by being screwed to each other to form a housing.

Description

Conductive device and roller conveying device

Technical Field

The present invention relates to an electrically conductive device for electrically grounding a roller shaft of a roller conveying device and a roller conveying device including the same.

Background

In a process of manufacturing components by processing various substrates such as a glass substrate for a display device, an electronic circuit substrate, and the like, for example, the substrates are generally conveyed by a roller conveyor. Static electricity is generated by rotation of a roller shaft of the roller conveying device or friction between the roller and the substrate, and thus the substrate or elements formed on the substrate may be degraded or damaged. As a countermeasure against the above problem, it is conceivable to provide an ionizer for removing static electricity in the substrate conveyance path or to electrically ground the roller shaft, for example.

For example, the technique described in patent document 1 relates to a grounding device that is attached to an end portion of a roller shaft and that grounds the roller shaft via a grounding line. In the above-described device, a conductive shaft is rotatably provided to a housing that can be mounted on an end portion of a roller shaft, and a ground wire is connected to the conductive shaft. With this configuration, the housing rotates in accordance with the rotation of the roller shaft, but the rotation of the conductive shaft, which causes the distortion of the ground wire, is suppressed.

[ Prior art documents ]

[ patent document ]

[ patent document 1] Korean patent No. 10-1401025 (for example, FIG. 3)

Disclosure of Invention

[ problems to be solved by the invention ]

The grounding device described in patent document 1 has the following problems: the number of parts is large, the structure is complicated, and the assembly requires a large amount of labor. In particular, when each component including a spring for biasing is assembled in a case and fixed by a screw, it is very difficult and requires a long time to perform a work of screwing with a tool while pressing the component to be thrown out by the restoring force of the spring.

The present invention has been made in view of the above problems, and a first object of the present invention is to provide a structure that is easily assembled in a device that is mounted on a roller shaft for the purpose of electrical grounding. A second object of the present invention is to provide a roller transport apparatus capable of preventing damage to a substrate due to static electricity by grounding a roller shaft.

[ means for solving problems ]

In order to achieve the first object, an embodiment of the present invention is a conductive device for electrically connecting a roller shaft of a roller conveying device to a ground line, the conductive device including: a housing having an engaging portion engaged with an end of the roller shaft; a shaft member formed of a conductive material and protruding from the inside of the housing to the outside through an opening provided in the housing; a bearing that rotatably supports the shaft member relative to the housing in the housing; and a conductive portion that elastically abuts against the shaft member and electrically connects the shaft member and the housing to form a conductive path.

Further, the housing includes: a main body portion formed of a conductive material and having an internal space capable of accommodating the bearing and the conductive portion; and a lid portion that is provided with a through hole that becomes the opening and that is engaged with the main body portion to close the internal space, thereby sealing the bearing and the conductive portion in the internal space; the body portion and the lid portion are integrated by screwing together screw portions provided in the body portion and the lid portion, thereby constituting the housing.

In the invention thus constituted, the assembly of the parts is completed by screwing the cover portion onto the main body portion in a state in which the bearing and the conductive portion supporting the shaft member are accommodated in the internal space of the main body portion constituting the housing. Therefore, assembly is exceptionally easy compared to the prior art. Further, since the shaft member is rotatable relative to the housing, the ground wire is connected to the shaft member, and therefore, even when the housing and the roller shaft rotate integrally, twisting of the ground wire can be suppressed.

In order to achieve the second object, another embodiment of the present invention is a roller conveyor including: a roller shaft rotating around the central shaft; a roller mounted on the roller shaft and rotating integrally with the roller shaft to convey an object to be conveyed in a predetermined conveying direction; the conductive device of the structure is arranged at the end part of the roll shaft; and the grounding wire is connected with the conducting device.

In the invention thus constituted, the substrate can be conveyed in a state in which the roller shaft is electrically grounded, and therefore damage to the substrate due to static electricity can be prevented.

[ Effect of the invention ]

As described above, according to the present invention, it is possible to construct a conductive device which can be easily assembled and can surely ground a roller shaft. Further, by mounting such a conductive device on the roller conveying device, damage to the substrate to be conveyed can be prevented.

Drawings

Fig. 1 is a diagram showing an embodiment of the present invention.

Fig. 2 is an exploded sectional view showing the internal structure of each component constituting the conductive device.

Fig. 3 is a flow chart showing steps of assembling the conductive device.

Fig. 4 is an assembled cross-sectional view of the conductive device.

Fig. 5 is a diagram showing a second embodiment of the conductive device of the present invention.

Fig. 6 is a diagram showing a third embodiment and a fourth embodiment of the conductive device of the present invention.

[ description of symbols ]

1. 2, 3, 4: conducting device

9: roller conveying device

10. 210, 310, 410: casing body (body, casing)

11: external screw thread (fastening part)

13. 213: internal thread

20. 320, and (3) respectively: spring (force applying component, conductive part)

30. 330: conductive block (abutting component, conductive part)

31: disk-shaped part

32: cylindrical part

33: concave part

40. 340, and (3): shaft member

41: lower part (expanding part)

42: lower end face

43: upper end part

44: internal screw thread (connecting part)

50: bearing assembly

51: outer ring

52: inner ring

53: rotary body

60. 260, 360: cover (casing)

61. 261: external thread

62: cylindrical part

63: upper end of

70: ground wire (grounding wire)

71: terminal fitting

80: fixing screw

90: gasket ring

100. 200, 300, 400: shell body

363: upper end of the cover part

420: plate spring (elastomer)

910: frame structure

920: roll shaft

921: one end of which

930: conveying roller (roller)

F: application of force

SP: inner space

S101 to S107: step (ii) of

Detailed Description

Fig. 1 is a diagram showing an embodiment of the present invention. More specifically, (a) of fig. 1 is a view showing an appearance of the first embodiment of the conductive device of the present invention. Fig. 1 (b) is a view showing an external appearance of a part of the roller conveyor equipped with the above-described conductive device. As shown in fig. 1 (a), the conductive device 1 has a structure in which a shaft member 40 is provided so as to protrude from a central axis of a substantially cylindrical housing 100.

The shaft member 40 is rotatable with respect to the housing 100 around a rotation axis substantially coincident with the central axis of the housing 100. A ground wire 70 is connected to a tip end of the shaft member 40 projecting from the housing 100 to the outside via a terminal fitting 71. A male screw 11 is formed coaxially with the central axis of the housing 100 at the end of the housing 100 on the side opposite to the side where the shaft member 40 is provided.

As shown in fig. 1 (b), the conductive device 1 is mounted on the roller conveying device 9. More specifically, the roller conveying device 9 includes: a pair of

frames

910, 910 arranged in parallel; a plurality of roller shafts 920 axially rotatably supported at both ends by the

frames

910 and 910; and a plurality of conveyance rollers 930 are provided on each roller shaft 920. The roller shaft 920 rotates to convey the substrate, not shown, whose lower surface is supported by the conveying roller 930 in a predetermined conveying direction. The roller shaft 920 is made of, for example, metal having conductivity, and the conveying roller 930 is made of, for example, resin having conductivity.

The conductive devices 1 are respectively installed at one end 921 of the respective roll shafts 920. That is, a female screw, not shown, is formed at one end 921 of each roller shaft 920, and the male screw 11 of the conductive device 1 is screwed into the female screw, whereby the conductive device 1 is attached to the end of the roller shaft 920 and electrically connected to the roller shaft 920. The conductive devices 1 mounted on the respective roller shafts 920 are electrically connected to each other via the ground line 70, and are finally connected to a predetermined ground electrode and grounded.

This prevents the roller 920 from generating static electricity and damaging the substrate during the substrate conveyance process. When the glass substrate is conveyed by the conveying roller 930, for example, the glass substrate, the roller shaft 920, and the conveying roller 930 are electrostatically charged due to friction between the glass substrate and the conveying roller 930. Without the conductive device as in the present embodiment, so-called sparks (spark) may occur in which the charged static electricity is discharged from the conveying roller 930 or the roller shaft 920 toward the substrate. Such a spark can be prevented by controlling the potential of the roller 920 with the conductive device 1, for example, electrically grounding it.

The housing 100 of the conductive device 1 rotates integrally with the roller 920 by the rotation of the roller 920. On the other hand, the ground wire 70 is attached to the shaft member 40, and the shaft member 40 is rotatable about a rotation axis coaxial with the central axis of the housing 100 with respect to the housing 100. Therefore, the shaft member 40 does not rotate in the state where the ground wire 70 is attached, and the ground wire 70 is prevented from being twisted with the rotation of the roller shaft 920.

Hereinafter, a more detailed structure of the conductive device 1 will be described with reference to fig. 2 to 4. Fig. 2 is an exploded sectional view showing an internal structure of each component constituting the conductive device, and fig. 4 is an assembled sectional view of the conductive device. Fig. 3 is a flowchart showing steps of assembling the conductive device.

As shown in fig. 2, the conductive device 1 includes: the housing body 10, the spring 20, the conductive block 30, the shaft member 40, the bearing 50, the cap 60, the ground wire 70, the fixing screw 80, and the washer 90. The shape of each member other than the ground line 70 has substantially axial symmetry, and as shown in fig. 1 and 2, the conductive device 1 is configured by coaxially assembling these members.

The case body 10 is a component integrally formed of a conductive material, for example, a metal material such as stainless steel, brass, or aluminum, and is pierced from the center of the upper end of a substantially cylindrical member to a predetermined depth, and has a cylindrical shape with an open upper end and a closed lower end. Thus, an internal space SP for accommodating each component described later is formed in the housing body 10. A female screw 13 is formed at the edge of the upper end opening of the housing body 10.

The spring 20 is a coil spring formed of a conductive and elastic material, such as a metal wire. The outer diameter of the spring 20 becomes a size limited in the inner space SP of the housing body 10.

The conductive block 30 is a part made of a conductive material, such as metal or carbon (graphite), and has the following structure: a cylindrical portion 32 having a diameter smaller than the inner diameter of the spring 20 is connected to a lower portion of the disc-shaped portion 31 having a diameter larger than the inner diameter of the spring 20. Further, a concave portion 33 is provided in the center of the upper surface of the disc-shaped portion 31. The conductive block 30 has the cylindrical portion 32 directed downward and above the spring 20 housed in the housing body 10. Then, the conductive block 30 is elastically supported by the spring 20 in a state where the columnar portion 32 is inserted into the spring 20.

The shaft member 40 is a rod-shaped member made of a conductive material, for example, a metal material such as stainless steel, brass, or aluminum, and has a lower portion 41 with a partially enlarged diameter and a lower end surface 42 formed in an inverted conical shape. In addition, a female screw 44 is formed at the upper end 43.

The bearing 50 is a radial rolling bearing, and a commercially available ball bearing can be used, for example. The outer diameter of shaft member 40 is set as follows: a suitable fit tolerance is applied relative to the inner diameter of the bearing 50 to bring the two into a clearance fit condition. This allows the shaft member 40 to be inserted with a slight force into the inner race of the bearing 50, for example.

The lid portion 60 is a cylindrical member having a male screw 61 provided around the periphery thereof. The male screw 61 is screwed into the female screw 13 of the housing body 10, and the housing body 10 and the lid portion 60 are integrated by screwing these screws, thereby constituting the housing 100. The material of the lid portion 60 is not particularly limited, and for example, the same material as the case body 10 can be used. The inner diameter of the cylindrical portion 62 of the cover 60 is set as follows: a suitable fit tolerance is applied with respect to the outer diameter of the bearing 50 to bring the two into a clearance fit condition. This allows the bearing 50 to be inserted with a slight force into the cover 60, for example.

On the other hand, the opening diameter of the upper end 63 of the cover portion 60 is slightly smaller than the outer diameter of the bearing 50. That is, the side wall surface of the cylindrical portion 62 is configured to protrude inward (toward the central axis) at the upper end thereof. This prevents the bearing 50 housed inside the cylindrical portion 62 from being projected upward beyond the lid portion 60. That is, the lid portion 60 has a function of sealing the spring 20, the conductive block 30, the shaft member 40, and the bearing 50 in the housing 100. The upper end of shaft member 40, which is rotatable with respect to case 100, protrudes from an opening provided at upper end 63 of lid 60.

A ground wire 70 is connected to an upper end of the shaft member 40. Specifically, the fixing screw 80 is screwed into the female screw 44 formed in the upper end portion 43 of the shaft member 40. The fixing screw 80 is screwed into the female screw 44 via the terminal fitting 71 and the washer 90 attached to one end of the ground wire 70, whereby the terminal fitting 71 is mechanically coupled to the shaft member 40, and the ground wire 70 is electrically connected to the shaft member 40.

Fig. 3 shows an example of a process for manufacturing the conductive device 1 by assembling these members. First, it is preferable that the spring 20 and the conductive block 30 are accommodated in the internal space SP of the case body 10 in this order with the opening of the case body 10 facing upward (step S101 and step S102). Further, the spring 20 and the conductive block 30 may be combined and stored in the housing body 10.

Next, the shaft member 40 is integrally housed in the housing body 10 in a state where it is inserted into the bearing 50 (step S103). Then, the lid portion 60 is fitted over the bearing 50, and is screwed to the housing body 10 while the lid portion 60 is pressed against the biasing force of the spring 20 (step S104).

The left side of fig. 4 (a) shows the state at this time. At the time when the lid portion 60 is placed on the bearing 50, the components housed in the housing body 10 are prevented from being thrown outward. In particular, since the lower end of shaft member 40 is pointed and concave portion 33 is provided in the upper portion of conductive block 30 receiving the pointed lower end, the shaft member 40 is prevented from sliding laterally on conductive block 30 and causing positional deviation. Therefore, the screwing operation of the lid portion 60 and the case body 10 is also an operation of mounting each component at a regular position. In addition, no jig or tool is required for the assembly work. In this way, the assembly work for integrating the respective parts is extremely simple in the above-described conduction device 1.

Returning to fig. 3, the thus assembled conductive device 1 is connected to the ground (step S106, step S107), and before this, the conductive device 1 may be engaged with the roller 920 (step S105). That is, there may be a method of engaging the conductive device 1 body with the roller 920 and then connecting the ground wire 70, and a method of engaging the conductive device 1 with the roller 920 in a state where the ground wire 70 is completely mounted (in this case, step S105 is performed after step S107). These methods can be appropriately selected depending on whether or not the workability on site is good.

The connection of the ground line 70 can be performed in the following manner. The washer 90 is inserted into the fixing screw 80 (step S106), and the fixing screw 80 is inserted through the mounting hole of the terminal fitting 71 mounted on the end portion of the ground wire 70 and tightened to the female screw 44 of the shaft member 40 (step S107), thereby connecting the ground wire 70 to the conductive device 1. In this case, although a tool such as a screwdriver is used to fasten the fixing screw 80, the shaft member 40 as the object to be attached is fixed to the larger conductive device 1 or the roller shaft 920, and therefore the support thereof is relatively easy.

The right diagram (a) of fig. 4 shows the state at this time. In this state, in the internal space SP of the housing 100, the conductive block 30 is electrically connected to the housing body 10 via the spring 20 and is biased upward by the restoring force of the spring 20 that has been pressed in. Shaft member 40 is pressed against the upper surface of conductive block 30, and therefore shaft member 40 is also urged upward.

Shaft member 40 is inserted through bearing 50. The diameter-expanded portion 41 of the shaft member 40 abuts against the lower surface of the bearing 50, thereby restricting upward movement of the shaft member 40 relative to the bearing 50. In other words, when the shaft member 40 is to be displaced upward, the bearing 50 is also displaced integrally.

As a result, the spring 20 imparts an upward urging force to the conductive block 30, the shaft member 40, and the bearing 50. Since the upper end 63 of the cover 60 restricts the displacement of the upper end of the bearing 50, the bearing 50 is pressed by the cover 60. This fixes the positions of the respective components in the vertical direction, and prevents the respective components from greatly shaking in the housing 100.

Fig. 4 (b) is a partial cross-sectional view showing the contact state of shaft member 40, bearing 50, and cover 60 in more detail. The bearing 50 is, for example, a ball bearing, and includes an outer ring 51, an inner ring 52, and a rolling body 53 as its main components. The rotor 53 rotates between the outer ring 51 and the inner ring 52, thereby effecting relative rotational movement between the outer ring 51 and the inner ring 52.

Here, the diameter-enlarged portion 41 of the shaft member 40 is in contact with the inner ring 52 of the bearing 50, but not in contact with the outer ring 51. In other words, the outer diameter of the diameter-expanded portion 41 is set so as to satisfy the relationship. On the other hand, the upper end 63 of the cover 60 is in contact with the outer ring 51 of the bearing 50, but not in contact with the inner ring 52. In other words, the opening diameter of the upper end 63 of the cover portion 60 is set so as to satisfy the relationship.

Therefore, the upward urging force F of the spring 20 indicated by the hollow arrow has the following effects: the shaft member 40 is pressed against the inner ring 52 of the bearing 50 so that no displacement occurs between the shaft member 40 and the inner ring 52, and the cover 60 is pressed against the outer ring 51 of the bearing 50 so that no displacement occurs between the cover 60 and the outer ring 51. On the other hand, the outer ring 51 and the inner ring 52 smoothly rotate with each other. As a result, the shaft member 40 is freely rotated with respect to the housing 100.

Shaft member 40 rotates relative to housing 100, and thereby the tip of shaft member 40 slides in a state of touching conductive block 30. Therefore, the following properties are required for the conductive block 30: good conductivity, low friction coefficient and high heat resistance. In the present embodiment, a carbon (graphite) block is used as a conductive block suitable for such a purpose.

As described above, the conductive device 1 of the present embodiment has a function of electrically grounding the roller shaft 920 of the roller conveyor 9. Specifically, a conductive path is formed to the ground electrode, not shown, via the case body 10, the spring 20, the conductive block 30, the shaft member 40, and the ground wire 70, each of which is made of a conductive material, and static electricity generated in the roller shaft 920 is removed. This prevents the substrate to be transported or the elements formed on the surface of the substrate from being damaged or deteriorated in characteristics due to static electricity.

The conductive device 1 can be assembled by a simple work of covering the lid portion 60 and screwing it after housing the main parts in the case body 10. Therefore, no special jig or tool is used, and the assembly can be performed with a small number of steps.

Other embodiments of the conductive device of the present invention will be described below. In these embodiments, a part of the structure is different from that of the first embodiment, but most of the structures are the same. Therefore, members having the same configurations and functions as those of the first embodiment are given the same reference numerals, and detailed description thereof may be omitted.

Fig. 5 is a diagram showing a second embodiment of the conductive device of the present invention. In the conductive device 2 of the second embodiment, a part of the structure of the housing is different from that of the first embodiment, and the structure is the same except this point. Specifically, in the case body 210 and the lid portion 260 constituting the case 200, the female screw 213 is formed on the case body 210 side, and the male screw 261 is formed on the lid portion 260 side, and both are screwed together. Even with such a configuration, the following effects can be obtained as in the first embodiment: the assembly is simple, and the roller shaft can be reliably grounded.

In addition, in this structure, the inner diameter of the upper portion of the housing body 210 can be made to coincide with the outer diameter of the bearing 50, for example. With such a configuration, in the step of housing the bearing 50 in the housing body 210 (step S103) in the assembly step, the cover 260 can be smoothly closed while suppressing the lateral play of the bearing 50. This further improves workability in assembly.

Fig. 6 is a diagram showing a third embodiment and a fourth embodiment of the conductive device of the present invention. More specifically, (a) of fig. 6 shows a third embodiment of the conductive device of the present invention, and (b) of fig. 6 shows a fourth embodiment of the conductive device of the present invention. In the conductive device 3 of the third embodiment shown in fig. 6 (a), the spring 320 is disposed above the bearing 50. More specifically, in this embodiment, a conductive block 330 made of carbon is disposed at the bottom of the internal space SP of the housing body 310, and a shaft member 340 is provided so as to abut on the upper surface of the conductive block 330. The shaft member 340 is accommodated in the housing body 310 in a state of being inserted into the bearing 50.

Thereafter, the spring 320 is loaded on the bearing 50 and the cover portion 360 is covered. The opening diameter of the cap upper end 363 is smaller than the outer diameter of the spring 320, thereby preventing flying of the spring 320. The lid 360 is screwed to the housing body 310, whereby the spring 320 contracts and the restoring force thereof urges the bearing 50 downward. Thereby, the shaft member 340 rotates in a state of being pressed by the conductive block 330.

In this case, since conduction is obtained between the shaft member 340 and the conductive piece 330 and between the conductive piece 330 and the housing body 310, respectively, the spring 320 does not need to be conductive. Further, as long as no problem occurs in terms of wear resistance, the shaft member 340 may be configured to abut against the housing main body 310 without a conductive block.

In this configuration, for example, by setting the inner diameter of the housing main body 310 to an inner diameter corresponding to the outer diameter of the bearing 50, the lateral play when the bearing 50 is housed in the housing main body 310 can be reduced to a level that is practically free from problems. Therefore, the spring 320 is further loaded and the lid 360 is tightly closed, whereby the conductive device 3 can be assembled and the assembling work becomes easier.

In this configuration, in order to arrange the spring 320 in the housing main body 310 with high positional accuracy and facilitate the subsequent attachment of the lid portion 360, it is preferable that a male screw be provided on the housing main body 310 and a female screw be provided on the lid portion 360, as shown in the drawing.

In the conductive device 4 of the fourth embodiment shown in fig. 6 (b), a plate spring 420 made of a material having conductivity and elasticity, for example, phosphor bronze, is provided in the housing 400 instead of the spring 20 and the conductive block 30 provided in the conductive device 1 of the first embodiment. The leaf spring 420 biases the shaft member 40 upward by its restoring force, thereby pressing the shaft member 40 against the bearing 50 and pressing the bearing 50 against the upper end 63 of the lid portion 60. Further, the housing body 410 and the shaft member 40 are electrically connected by being brought into contact with each other. That is, the plate spring 420 elastically and electrically connects the shaft member 40 and the housing body 410. This can further reduce the number of parts.

In the conductive devices 3 and 4 according to these embodiments, the roller shaft may be electrically grounded via the conductive devices. The assembly steps of housing the main components in the case body and closing the main components with the lid are also the same as those of the first embodiment. Therefore, the assembly of the conductive device can be easily performed.

As described above, in the first embodiment, the housing body 10 and the lid portion 60 function as the "body portion" and the "lid portion" of the present invention, respectively, and they function integrally as the "housing" of the present invention. The shaft member 40 and the bearing 50 function as a "shaft member" and a "bearing" according to the present invention, respectively. The spring 20 functions as an "urging member" of the present invention, while the conductive block 30 functions as an "abutment member" of the present invention, and these members function integrally as a "conductive portion" of the present invention. The male screw 11 provided in the housing body 10 corresponds to an "engagement portion" of the present invention, and the female screw 44 provided in the shaft member 40 corresponds to a "connection portion" of the present invention. The ground line 70 corresponds to the "ground line" of the present invention.

In the third embodiment, the spring 320 functions as the "biasing member" of the present invention, while the conductive block 330 functions as the "contact member" of the present invention, and these integrally function as the "conductive portion" of the present invention. On the other hand, in the fourth embodiment, the leaf spring 420 functions as the "elastic body" of the present invention.

The present invention is not limited to the above-described embodiments, and various modifications can be made to the embodiments other than the above-described embodiments without departing from the gist thereof. For example, in the embodiment, the conductive device 1 is connected to the roller 920 via the external thread 11 provided on the housing body 10. However, the structure for engaging the conductive device with the roller shaft is not limited to this, and other structures may be suitably used.

In addition, for example, in the first to third embodiments, the coil spring is used as the source of generation of the urging force, but instead, a plate spring or a conductive resin material as used in the fourth embodiment may be used to generate the urging force.

In the first embodiment, for example, the conductive block 30 and the housing body 10 are electrically connected to each other by the spring 20 that generates the biasing force, but the configuration for generating the biasing force and the configuration for ensuring the electrical connection do not need to be the same, and they may be realized by different members.

In the first embodiment, for example, in order to facilitate the attachment and detachment of the parts, the shaft member 40 and the inner ring 52 of the bearing 50 and the cover 60 and the outer ring 51 of the bearing 50 are in a clearance fit state. Alternatively, either one may be set to a state of intermediate fitting or close fitting. For example, when the shaft member and the bearing are tightly fitted to each other, the shaft member and the inner ring are fixed to each other at the time of assembly, and therefore, it is not necessary to provide the shaft member with a portion having an enlarged diameter.

The entire housing body 10 and the like of the above embodiment are formed of a conductive material (e.g., metal), but the present invention is not limited thereto. That is, it is sufficient to secure a conductive path connecting the roller shaft and the conductive portion (spring and conductive block), and a portion not participating in the conductive path may not have conductivity.

In the above embodiment, the ground wire 70, the fixing screw 80, and the washer 90 are included in a part of the configuration of the conductive device, but when the conductive device is distributed as a product, these components (particularly, the ground wire) may be handled as external components not included in the conductive device.

As described above with reference to the exemplary embodiments, in the conductive device of the present invention, for example, the conductive portion may have the following configuration: the pressing member is formed of a conductive material, and includes an abutting member that abuts against the shaft member and is electrically connected to the housing, and a biasing member that biases the shaft member and the abutting member in a direction of approach to each other to apply a pressing force. According to this configuration, electrical conduction can be stably ensured even in the sliding between the contact member and the shaft member caused by the rotation of the shaft member.

In this case, for example, the urging member may be an elastic body formed of a material having conductivity, interposed between the abutting member and the housing. According to this configuration, the urging member has both a function of applying an urging force to the contact member and a function of securing conduction, and the number of parts can be reduced.

In addition, for example, the conductive portion may be an elastic body formed of a material having conductivity, interposed between the shaft member and the housing. According to this configuration, the shaft member and the housing are elastically and electrically connected by the conductive portion, and as described above, the shaft member can be provided with both a function of applying a force to the shaft member and a function of securing electrical conduction.

The bearing may be a radial bearing in which the inner ring and the outer ring are rotatable relative to each other about one rotation axis, the outer ring is in contact with the housing, and the shaft member may have a shape in which one end of a rod-like member having a diameter equal to or smaller than the inner diameter of the inner ring is expanded in diameter as compared with the inner diameter of the inner ring, and the shaft member may be inserted into the inner ring in a state in which the one end is positioned in the housing and the other end opposite to the one end is positioned outside the housing. According to this configuration, the positional relationship of the components is defined by the contact of the housing and the shaft member with the bearing, and the shaft member can be smoothly rotated with respect to the housing.

In addition, for example, a connection site for connecting a ground wire may be provided in a portion of the shaft member exposed to the outside of the housing. According to this configuration, even if the housing rotates in accordance with the rotation of the roller shaft, the rotation of the shaft member to which the ground wire is connected can be avoided, and therefore, there is no case where the ground wire is twisted or the rotation of the roller shaft is hindered by the connection of the ground wire.

[ industrial applicability ]

The present invention can be suitably applied to the application of constituting a roller conveying device for conveying various substrates such as a glass substrate and an electronic circuit substrate.

Claims

1. A conductive device for electrically connecting a roller shaft of a roller conveying device to a ground wire, comprising:

a housing having an engaging portion engaged with an end of the roller shaft;

a shaft member formed of a conductive material and protruding from the inside of the housing to the outside through an opening provided in the housing;

a bearing that rotatably supports the shaft member relative to the housing in the housing; and

a conductive portion that elastically abuts against the shaft member and electrically connects the shaft member and the housing to form a conductive path;

the housing includes:

a main body portion formed of a conductive material and having an internal space capable of accommodating the bearing and the conductive portion; and

a lid portion that is provided with a through hole that becomes the opening and that is engaged with the main body portion to close the internal space, thereby sealing the bearing and the conductive portion in the internal space;

the body portion and the lid portion are integrated by screwing together screw portions provided in the body portion and the lid portion, thereby forming the housing.

2. The conductive device of claim 1, wherein

The conductive part has:

an abutting member formed of a material having conductivity, abutting on the shaft member, and electrically connected to the housing; and

and an urging member that urges the shaft member and the abutment member in a direction of approach to each other to apply a pressing force.

3. The conductive device of claim 2, wherein the force application member is an elastomer formed of a material having conductivity, interposed between the abutment member and the housing.

4. The conductive device according to claim 1, wherein the conductive portion is an elastic body formed of a material having conductivity, interposed between the shaft member and the housing.

5. The electrical conducting device according to any one of claims 1 to 4, wherein the bearing is a radial bearing in which an inner ring is freely rotatable around a rotation axis opposite to an outer ring abutting on the housing,

the shaft member has a shape in which one end portion is expanded in diameter as compared with an inner diameter of the inner ring, the one end portion being one end portion of a rod-shaped member having a diameter equal to or smaller than the inner diameter of the inner ring, and the shaft member is inserted into the inner ring in a state in which the one end portion is positioned within the housing and the other end portion opposite to the one end portion is positioned outside the housing.

6. The electrically conductive device according to any one of claims 1 to 5, wherein a portion of the shaft member exposed to the outside of the housing has a connection site for connecting the ground wire.

7. A roller conveying apparatus comprising:

a roller shaft rotating around the central shaft;

a roller mounted on the roller shaft and rotating integrally with the roller shaft to convey an object to be conveyed in a predetermined conveying direction;

the conductive device as claimed in any one of claims 1 to 6, which is installed at an end of the roller shaft; and

and the grounding wire is connected with the conducting device.