Patent Description:
The present invention relates to a system and method for inspecting an outer appearance, and more particularly, to a system and method for inspecting an outer appearance of a secondary battery, which inspects whether there is a defect on the outer appearance of the manufactured secondary battery.

Recently, as prices of energy sources rise due to depletion of fossil fuels and interests about environmental pollution are amplified, a need for eco-friendly alternative energy sources is indispensable for life in the future. Accordingly, research continues on various power generation technologies using sunlight, wind power, tidal power, and so on, and there is also a continuing great interest in power storage systems, such as batteries, for more efficiently using electrical energy generated through the technologies.

Moreover, as the technical development of and a demand for mobile electronic devices and electric vehicles using batteries increase, a demand for batteries as energy sources rapidly increases. Accordingly, much research is conducted on batteries that can meet the various needs.

Batteries that store electrical energy may be generally classified into primary batteries and secondary batteries. While the primary batteries are disposable consumable batteries, the secondary batteries are rechargeable batteries manufactured using a material in which a redox process between a current and a substance is repeatable. That is, when a reduction reaction is performed on the material by the current, a power supply is charged, and when an oxidation reaction is performed on the material, the power supply is discharged. Such a charging-discharging is repeatedly performed to generate electricity.

In particular, lithium secondary batteries such as lithium-ion batteries and lithium-ion polymer batteries, which have advantages such as high energy density, discharge voltage, and output stability, are in high demand in terms of a material.

Secondary batteries are rechargeable unlike primary batteries, and classified into a coin type battery, a cylinder type battery, a prismatic type battery, and a pouch type battery according to the shape of cases.

The secondary batteries made through a manufacturing process are inspected for an occurrence of defect, and a defective product is discriminated accordingly. It may be primarily inspected whether an outer appearance of each of the secondary batteries is defective. Here, it is inspected whether there are scratches, wrinkles, or the like, on the outer appearance and whether swelling occurs in the secondary battery.

When a side surface of a cylinder type secondary battery is inspected during inspection of an outer appearance of the cylinder type secondary battery, the inspection of the side surface is carried out while allowing the cylinder type secondary battery to rotate in an upright state. Thus, there is a case in which the inspection of the outer appearance is not properly carried out on a portion at which the cylinder type secondary battery is gripped. In addition, as the size and the capacity of the cylinder type secondary battery increase, there are also problems that stability decreases during transfer and accuracy of the inspection decreases.

In order to solve these problems, there is a need for an outer appearance inspection method for the secondary battery, which is capable of precisely inspecting the entire outer appearance of the secondary battery, capable of stably transferring even the secondary battery having an increased size and capacity, and improves accuracy of the inspection.

Document <CIT> discloses an appearance inspection apparatus for a secondary battery of known type.

The present invention has been devised to solve the problems as above and an object of the present invention is to provide a system and method for inspecting an outer appearance of a secondary battery, which precisely inspect the entire outer appearance of the secondary battery by modifying an inspecting device that inspects the outer appearance of the secondary battery, increase stability during transfer of the secondary battery by modifying a transfer device that transfers the secondary battery to be inspected, and improve accuracy of the outer appearance inspection of the secondary battery.

An outer appearance inspection system, for inspecting an outer appearance of a secondary battery, according to the present invention is defined in the appended claims. An outer appearance inspection method is also provided.

The outer appearance inspection system, which inspects the outer appearance of the secondary battery, according to the present invention includes the transfer device, which transfers the secondary battery according to the inspection position, the top and bottom inspecting device, which is disposed at the first inspection position and inspects the upper portion and the lower portion of the secondary battery, the side surface inspecting device, which is disposed at the second inspection position and inspects the side surface of the secondary battery and the secondary battery for the swelling, and the rotating device which is disposed at the second inspection position and rotates the secondary battery. The side surface inspecting device inspects the side surface of the secondary battery and the secondary battery for the swelling in the state in which the secondary battery lies on the transfer device.

Accordingly, the entire outer appearance of the secondary battery may be precisely inspected, the false inspection may be minimized, and the shaking during the transfer of the secondary battery may be minimized to improve the stability. In addition, the accuracy of the outer appearance inspection of the secondary battery may be improved, and the outer appearance defect may be minimized.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings to enable those skilled in the art to which the present invention pertains to easily carry out the present invention.

Like reference numerals refer to like elements throughout the whole specification.

Moreover, terms or words used in this specification and claims should not be restrictively interpreted as ordinary meanings or dictionary-based meanings, but should be interpreted as meanings and concepts conforming to the scope of the present invention on the basis of the principle that an inventor can properly define the concept of a term to describe and explain his or her invention in the best ways.

The present invention provides an outer appearance inspection system as Embodiment <NUM>.

<FIG> is a schematic plan view illustrating an outer appearance inspection system <NUM> according to Embodiment <NUM> of the present invention.

Referring to <FIG>, the outer appearance inspection system <NUM> for inspecting an outer appearance of a secondary battery <NUM> may include a transfer device <NUM>, a top and bottom inspecting device <NUM>, a side surface inspecting device <NUM>, and a rotating device <NUM>.

<FIG> and <FIG> are a plan view and a side view, respectively, each of which schematically illustrates the transfer device <NUM> of the outer appearance inspection system <NUM> according to Embodiment <NUM> of the present invention.

The secondary battery <NUM> may move to an inspection position, at which each of inspections is carried out, for the outer appearance inspection of the secondary battery <NUM>.

The outer appearance inspection system <NUM> according to Embodiment <NUM> of the present invention includes the transfer device <NUM>.

Referring to <FIG> and <FIG>, the transfer device <NUM> may have a shape of a conveyor. When the transfer device <NUM> has the shape of a conveyor, the secondary battery <NUM> may be transferred on a top surface of the transfer device <NUM> according to proceeding of the conveyor.

A path along which the secondary battery <NUM> is transferred on the transfer device <NUM> may have an oval shape when the transfer device <NUM> is viewed downward from top. The secondary battery <NUM> may be inspected while moving along the path having an oval shape.

A first inspection position <NUM> may be provided at a left lower portion, and a second inspection position <NUM> may be provided at a right lower portion on the top surface of the transfer device <NUM> in <FIG>. However, each of the inspection positions is just one example and thus, is not necessarily limited thereto. The inspection positions may be provided at other positions.

A top and bottom inspection for the secondary battery <NUM> may be carried out at the first inspection position <NUM>, and side surface and swelling inspections for the secondary battery <NUM> may be carried out at the second inspection position <NUM>. Each of the inspections will be described later in detail again.

The secondary battery <NUM> subject to inspection may start to be transferred from a left upper portion by the transfer device <NUM>, on the top surface of the transfer device <NUM> in <FIG>. Here, the secondary battery <NUM> may be transferred in a lying state so that a longitudinal direction and a proceeding direction of the secondary battery <NUM> are perpendicular to each other. For example, in <FIG>, when the secondary battery <NUM> is a cylindrical type, the secondary battery <NUM> may start to be transferred in a lying state so that an axial direction thereof matches an up and down direction in <FIG>. For reference, the secondary battery <NUM> is not limited to an example of the present invention, and may have various types of various shapes.

As an example of a component for efficiently transferring the secondary battery <NUM>, the transfer device <NUM> of the outer appearance inspection system <NUM> according to Embodiment <NUM> of the present invention may be a conveyor including a linear motion guide <NUM>.

When the transfer device <NUM> is the conveyor including the linear motion guide <NUM>, the secondary battery <NUM> may be transferred to each of the inspection positions by a linear motion of the linear motion guide <NUM> during the outer appearance inspection.

The linear motion guide <NUM> may be generally constituted by a rail <NUM> and a block <NUM> that moves along the rail <NUM>. Thus, the transfer device <NUM> may include the linear motion guide <NUM> having a configuration, in which the block <NUM> moves along the rail <NUM> provided on the top surface of the transfer device <NUM>, and the secondary battery <NUM> to be inspected may be transferred while lying on a top surface of the block <NUM>.

When the transfer device <NUM> is the conveyor including the linear motion guide <NUM>, there may be an effect that shaking is minimized to improve stability when the secondary battery <NUM> is transferred. In addition, a transfer speed may be adjusted according to the inspection process.

<FIG> is a schematic plan view illustrating a top and bottom inspecting device <NUM> of the outer appearance inspection system <NUM> according to Embodiment <NUM> of the present invention.

When the secondary battery <NUM> transferred by the transfer device <NUM> reaches the first inspection position <NUM>, the inspection of an upper portion and a lower portion of the secondary battery <NUM> may be carried out. As an example of a component for inspecting the upper portion and the lower portion of the secondary battery <NUM>, the outer appearance inspection system <NUM> according to Embodiment <NUM> of the present invention may include the top and bottom inspecting device <NUM>.

Referring to <FIG>, the top and bottom inspecting device <NUM> may be disposed at the first inspection position <NUM> and inspect the upper portion and the lower portion of the secondary battery <NUM>. Specifically, the upper portion and the lower portion of the secondary battery <NUM> may be inspected through the top and bottom inspecting device <NUM> for determining whether wrinkles, dents, scratches, foreign matters, contaminant, discoloration, short-circuit marks, or the like occur.

For the efficient outer appearance inspection for the upper portion and the lower portion of the secondary battery <NUM>, the top and bottom inspecting device <NUM> may include an upper portion inspecting machine <NUM>, which inspects the upper portion of the secondary battery <NUM>, and a lower portion inspecting machine <NUM> which inspects the lower portion of the secondary battery <NUM>.

The upper portion inspecting machine <NUM> and the lower portion inspecting machine <NUM> of the top and bottom inspecting device <NUM> may be disposed at both sides, respectively, of the transfer device <NUM> at the first inspection position <NUM>. Thus, in <FIG>, the upper portion inspecting machine <NUM> may be disposed at an upper side and the lower portion inspecting machine <NUM> may be disposed at a lower side at the first inspection position <NUM>. As the upper portion and the lower portion of the secondary battery <NUM> may be inspected simultaneously, the position of the upper portion inspecting machine <NUM> and the position of the lower portion inspecting machine <NUM> may be switched.

A camera <NUM> may be provided inside each of the upper portion inspecting machine <NUM> and the lower portion inspecting machine <NUM> of the top and bottom inspecting device <NUM>. The camera <NUM> provided in the inside may photograph conditions of the upper and lower outer appearances of the secondary battery <NUM> to inspect whether there is an abnormality.

As the top and bottom inspecting device <NUM> of the outer appearance inspection system <NUM> has the camera <NUM> provided therein and includes the upper portion inspecting machine <NUM> and the lower portion inspecting machine <NUM>, the upper and lower outer appearances of the secondary battery <NUM> in the lying state on the top surface of the transfer device <NUM> may be simultaneously inspected. Thus, a time and a space may be reduced to increase efficiency of the inspection process.

The secondary battery <NUM> after the inspection of the upper portion and the lower portion by the top and bottom inspecting device <NUM> is transferred by the transfer device <NUM> and reaches the second inspection position <NUM>. The secondary battery <NUM> that reaches the second inspection position <NUM> is inspected for conditions of an outer appearance of the side surface and for swelling. As component for inspecting the secondary battery <NUM> for conditions of the side surface and for swelling, the outer appearance inspection system <NUM> according to Embodiment <NUM> of the present invention comprises the side surface inspecting device <NUM>.

The side surface inspecting device <NUM> is disposed at the second inspection position <NUM> is configured to inspect the secondary battery <NUM> for conditions of the side surface and for swelling. Specifically, the side surface of the secondary battery <NUM> may be inspected through the side surface inspecting device <NUM> for whether there are wrinkles, dents, scratches, rust, foreign matters, contaminant, discoloration, or the like, and for whether other identifying phrases match a product. In addition, the secondary battery <NUM> may be inspected for defect through the inspection for swelling.

In the related art, when the secondary battery <NUM> is a cylindrical type, the outer appearance inspection for the side surface is carried out in a state in which the secondary battery <NUM> stands upright. Thus, this is a method in which the secondary battery <NUM> is fixed for the inspection and the side surface of the secondary battery <NUM> is inspected while the secondary battery <NUM> rotates. However, there is a problem that the outer appearance inspection is inefficient in a portion gripped to fix the secondary battery <NUM>.

As an example of a component for solving this problem, the side surface inspecting device <NUM> of the outer appearance inspection system <NUM> according to Embodiment <NUM> of the present invention may be a 3D camera including a light source device <NUM> and a mirror <NUM>.

In the side surface inspecting device <NUM> that is the 3D camera, the light source device <NUM> may emit light along the side surface of the secondary battery <NUM>, and the mirror <NUM> may reflect the light emitted by the Light source device <NUM>.

As an example in which the side surface inspecting device <NUM> that is the 3D camera operates, the light source device <NUM> may emit the light having a specific pattern onto the side surface of the secondary battery <NUM>, and a change amount of the pattern may be calculated to recognize the outer appearance of the secondary battery <NUM>. In addition, the mirror <NUM> may reflect the light in order to increase an angle and range to carry out the inspection. Thus, data about the side surface of the secondary battery <NUM> may be acquired in a 3D type based on the change amount of the pattern caused by the light of the 3D camera. This is just one of operation modes of the 3D camera and thus, is not necessarily limited thereto.

The side surface inspecting device <NUM> may further include a unit such as a light unit, which additionally supplies light necessary for the operation of the 3D camera.

When the side surface inspecting device <NUM> is the 3D camera including the light source device <NUM> and the mirror <NUM>, it is possible to inspect all portions of the side surface even though the secondary battery <NUM> has a shape like the cylindrical shape of which a side surface is a curved surface. Accordingly, there may be effects of improving detectability and minimizing false inspection.

<FIG> is a schematic front view illustrating a first side surface inspecting machine <NUM> of the side surface inspecting device <NUM> of the outer appearance inspection system <NUM> according to Embodiment <NUM> of the present invention.

As an example of a component for increasing the efficiency of the side surface inspection for the secondary battery <NUM>, the side surface inspecting device <NUM> of the outer appearance inspection system <NUM> according to Embodiment <NUM> of the present invention may include a first side surface inspecting machine <NUM> and a second side surface inspecting machine <NUM>.

The first side surface inspecting machine <NUM> may inspect a portion of the side surface of the secondary battery <NUM>, and the second side surface inspecting machine <NUM> may inspect a portion of the side surface of the secondary battery <NUM>, which is not inspected by the first side surface inspecting machine <NUM>.

Preferably, each of the first side surface inspecting machine <NUM> and the second side surface inspecting machine <NUM> may be the 3D camera described above, which includes the light source device <NUM> and the mirror <NUM>.

When the side surface inspecting device <NUM> includes the first side surface inspecting machine <NUM> and the second side surface inspecting machine <NUM>, the secondary battery <NUM> after the inspection of the upper portion and the lower portion by the top and bottom inspecting device <NUM> may be inspected for conditions of the side surface and for swelling at the second inspection position <NUM> by the first side surface inspecting machine <NUM> and the second side surface inspecting machine <NUM>.

Based on the order in which the secondary battery <NUM> passes the second inspection position <NUM> through the transfer device <NUM>, the inspection of the secondary battery <NUM> may be carried out by the first side surface inspecting machine <NUM> in the first half, and carried out by the second side surface inspecting machine <NUM> in the second half. Thus, in <FIG>, the first side surface inspecting machine <NUM> may be disposed at a left side of the second inspection position <NUM>, and the second side surface inspecting machine <NUM> may be disposed at a right side of the second inspection position <NUM>. This is just one example and thus, the position of the first side surface inspecting machine <NUM> and the position of the second side surface inspecting machine <NUM> may be switched.

The secondary battery <NUM> after the inspection of the upper portion and the lower portion may be transferred by the transfer device <NUM> in the lying state on the top surface of the transfer device <NUM>, and the disposed state may be changed at the second inspection position <NUM> by the rotating device <NUM>. The rotating device <NUM> will be described in detail later.

In the secondary battery <NUM> after changing of the disposed state, a portion of the side surface may be inspected by the first side surface inspecting machine <NUM>. As an example of the portion of the side surface, when the secondary battery <NUM> is a cylindrical type, a portion that rotates at an angle of <NUM> degrees on the side surface having a radius of <NUM> degrees may be inspected. The range of the portion of the side surface is not limited thereto and thus, may change.

The secondary battery <NUM> inspected by the first side surface inspecting machine <NUM> may be changed to be in the disposed state for inspection of the other side surface by the rotating device <NUM>. The rotating device <NUM> will be described in detail later.

In the secondary battery <NUM> after the changing of the disposed state, the portion of the side surface, which is not inspected by the first side surface inspecting machine <NUM>, may be inspected by the second side surface inspecting machine <NUM>. Like in the example described above, when the portion that rotates at an angle of <NUM> degrees on the side surface of the secondary battery <NUM> is inspected, a remaining portion that rotates at an angle of <NUM> degrees may be inspected. The range of the side surface of the secondary battery <NUM>, which is inspected by the second side surface inspecting machine <NUM>, is not limited thereto and thus, may change.

When the side surface inspecting device <NUM> includes the first side surface inspecting machine <NUM> and the second side surface inspecting machine <NUM>, a portion that is not properly inspected in the side surface of the secondary battery <NUM> may be reduced to increase the efficiency of the inspection.

As component for disposing the secondary battery <NUM> to be in an appropriate state to be inspected, the outer appearance inspection system <NUM> according to Embodiment <NUM> of the present invention includes the rotating device <NUM>.

The rotating device <NUM> is disposed at the second inspection position <NUM>, and is configured to rotate the secondary battery <NUM> to allow the secondary battery <NUM> to be in a state appropriate for each of the inspections.

The rotating device <NUM> may include a first rotating machine <NUM> and a second rotating machine <NUM>. The first rotating machine <NUM> may rotate the secondary battery <NUM> after the inspecting of the upper portion and the lower portion by the top and bottom inspecting device <NUM>, into a state in which the side surface is inspectable by the first side surface inspecting machine <NUM>, and the second rotating machine <NUM> may rotate the secondary battery <NUM> after the inspecting of the portion of the side surface by the first side surface inspecting machine <NUM>, into a state in which the other portion of the side surface is inspectable by the second side surface inspecting machine <NUM>.

The first rotating machine <NUM> is disposed at an entrance of the second inspection position <NUM>. Specifically, the first rotating machine <NUM> may be disposed at a position that the secondary battery <NUM> passes right before reaching the position, at which the first side surface inspecting machine <NUM> is disposed, at the second inspection position <NUM> of the path along which the secondary battery <NUM> is moved by the transfer device <NUM>.

As described above, the first rotating machine <NUM> rotates the secondary battery <NUM>, which is inspected by the top and bottom inspecting device <NUM> in the lying state so that the longitudinal direction and the proceeding direction of the secondary battery <NUM> perpendicularly cross each other, so that the longitudinal direction of the secondary battery <NUM> and the traveling direction of the transfer device <NUM> are parallel to each other. For example, in <FIG>, when the secondary battery <NUM> is a cylindrical type, the secondary battery <NUM> may rotate in a lying state so that the axial direction thereof matches a left and right direction on <FIG>.

The second rotating machine <NUM> may be disposed between the first side surface inspecting machine <NUM> and the second side surface inspecting machine <NUM> at the second inspection position <NUM>. For example, the secondary battery <NUM> may be transferred by the transfer device <NUM> in order of the first side surface inspecting machine <NUM>, the second rotating machine <NUM>, and the second side surface inspecting machine <NUM>.

As described above, the second rotating machine <NUM> rotates the secondary battery <NUM>, which is inspected by the first side surface inspecting machine <NUM> in the lying state in which the longitudinal direction and the proceeding direction of the secondary battery <NUM> are parallel to each other, at an angle of <NUM> degrees so that a top surface and a bottom surface of the secondary battery <NUM> are reversed. For example, when the secondary battery <NUM> is a cylindrical type, the secondary battery <NUM> may rotate at an angle of <NUM> degrees so that the side surface of the secondary battery <NUM>, which faces upward in the first side surface inspecting machine <NUM>, faces the transfer device <NUM>.

When the rotating device <NUM> includes the first rotating machine <NUM> and the second rotating machine <NUM>, the secondary battery <NUM> may be disposed to be in the appropriate state to be inspected when the secondary battery <NUM> is disposed at each of the inspection positions by the transfer device <NUM>. Accordingly, there may be an effect that the efficiency of the process increases.

As an example of a component for loading the secondary battery <NUM> to be inspected on the transfer device <NUM>, the outer appearance inspection system <NUM> according to Embodiment <NUM> of the present invention may further include a loading device <NUM>.

The loading device <NUM> may load as many as a preset number of the secondary battery <NUM> of which the outer appearance is inspected. For example, when the transfer device <NUM> is the conveyor including the linear motion guide <NUM>, eight secondary batteries <NUM> may be loaded on a top surface of the block <NUM> that moves along the rail <NUM>. In this case, the eight secondary batteries <NUM> may constitute one set and pass each of the inspection positions.

When loading device <NUM> may load as many as the preset number of the secondary battery <NUM> on the transfer device <NUM>, a part of the process may be automated to increase the efficiency.

The secondary battery <NUM> to be inspected may be stored in a tray <NUM> before being loaded on the transfer device <NUM>. Here, the outer appearance inspection system <NUM> may be provided with a tray inlet <NUM>, through which the tray <NUM> in which the secondary batteries <NUM> to be loaded on the transfer device <NUM> through the loading device <NUM> are stored may enter, and a tray outlet <NUM> through which the empty tray <NUM> after the loading of all the stored secondary batteries <NUM> on the transfer device <NUM> by the loading device <NUM> may be discharged.

As an example of a component for discriminating defective secondary batteries <NUM> as a result of the inspections during the process, the outer appearance inspection system <NUM> according to Embodiment <NUM> of the present invention may further include a discriminating device <NUM>.

The discriminating device <NUM> may discriminate the defective secondary batteries <NUM> in terms of the outer appearance on the basis of the results of inspecting the secondary battery <NUM>, which are received from each of the inspecting devices. The secondary batteries <NUM> may be classified into a defective product and a good product by the discriminating device <NUM>.

<FIG> is a schematic perspective view illustrating a first conveyor <NUM> of the outer appearance inspection system <NUM> according to Embodiment <NUM> of the present invention.

As an example of a component for transferring the secondary batteries <NUM> after completion of the discrimination, the outer appearance inspection system <NUM> according to Embodiment <NUM> of the present invention may further include a first conveyor <NUM>.

The first conveyor <NUM> may be connected to the discriminating device <NUM> and transfer the secondary batteries <NUM>, each of which is determined to be a defective product or a good product. Here, the first conveyor <NUM> may be a pocket conveyor including a pocket <NUM> in which each of the discriminated secondary batteries <NUM> may be put individually, in order to prevent problems that may occur during the transfer.

When each of the secondary batteries <NUM> is transferred in a state of being put in the pocket <NUM> individually, collision with other secondary batteries <NUM> may be prevented to reduce the likelihood that an additional problem may occur in the secondary batteries <NUM> that are normal as a result of the inspection, and prevent the secondary batteries <NUM>, which are defective, from being mixed with the normal secondary batteries <NUM>.

The outer appearance inspection system <NUM> may further include a second conveyor <NUM> capable of transferring the secondary batteries <NUM>, which are found abnormal and determined to be defective according to the result of the inspection, among the secondary batteries <NUM> transferred by the first conveyor <NUM>.

The second conveyor <NUM> may separate the secondary batteries <NUM>, which are defective products, based on a discrimination result of the discriminating device <NUM>. As the defective secondary batteries <NUM> need to be separated from the secondary batteries <NUM> transferred along the first conveyor <NUM> during the transfer, a conveyor using a magnetic property of a magnet, or the like, may be used as the second conveyor.

Additionally, the outer appearance inspection system <NUM> according to Embodiment <NUM> of the present invention may include other components necessary for the process. For example, the outer appearance inspection system <NUM> may further include a good product storage box <NUM>, in which the secondary batteries <NUM> that are transferred along the first conveyor <NUM> and not abnormal as the result of the inspection are stored, and a defective product storage box <NUM> in which the secondary batteries <NUM> that are transferred by the second conveyor <NUM> and abnormal as the result of the inspection are stored.

In the outer appearance inspection system <NUM> according to Embodiment <NUM> of the present invention, shaking of the secondary batteries <NUM> may be minimized during the transfer and collision with the secondary batteries <NUM> may be prevented to increase stability. Moreover, the entire side surface of the secondary battery <NUM> may be inspected and detectability may be improved by the 3D inspection to reduce the false inspection. Accordingly, the efficiency of inspection may be increased.

The present invention provides, as Embodiment <NUM>, an outer appearance inspection method that inspects an outer appearance of a cylindrical type secondary battery.

<FIG> is a flowchart illustrating an outer appearance inspection method according to Embodiment <NUM> of the present invention.

Hereinafter, the detailed descriptions of the same components as the components of the outer appearance inspection system <NUM> according to Embodiment <NUM> of the present invention will be omitted.

Referring to <FIG>, the outer appearance inspection method according to Embodiment <NUM> of the present invention may start with a loading process (S10) of loading a secondary battery <NUM>, of which an outer appearance is subject to inspection, on a transfer device <NUM> by a loading device <NUM>.

As described in Embodiment <NUM>, as many as a preset number of the secondary batteries <NUM> may be loaded on the transfer device <NUM> in the loading process. Here, the secondary battery <NUM> that is a cylindrical type may be loaded for a top and bottom inspection in a lying state so that an axial direction and a proceeding direction of the secondary battery <NUM> are perpendicular to each other.

When the specific number of secondary batteries <NUM> are loaded on the transfer device <NUM>, a transferring process (S20) may be carried out in which the secondary battery <NUM> is transferred by the transfer device <NUM>.

In the transferring process (S20) by the transfer device <NUM>, the secondary battery <NUM> may move to each of inspection positions for the outer appearance inspection. That is, the outer appearance inspection method for the secondary battery <NUM> may be carried out in order according to traveling of the transfer device <NUM>.

The transfer device <NUM> used in the transferring process (S20) of the outer appearance inspection method according to Embodiment <NUM> of the present invention may include a linear motion guide <NUM>, and the secondary battery <NUM> may be transferred by a linear motion of the linear motion guide <NUM> in the transferring process (S20). Thus, shaking of the secondary battery <NUM> may be minimized in the transferring process (S20).

When the secondary battery <NUM> is transferred through the transferring process (S20), a top and bottom inspecting process (S30) may be carried out in which an upper portion and a lower portion are inspected by a top and bottom inspecting device <NUM>. In the top and bottom inspecting process (S30), as described in Embodiment <NUM>, the upper portion and the lower portion of the secondary battery <NUM> may be inspected for whether there are wrinkles, dents, scratches, foreign matters, contaminant, discoloration, short-circuit marks, or the like.

A first rotating process (S40), in which the secondary battery <NUM> that is a cylindrical type is rotated by a first rotating machine <NUM> so that the axial direction of the secondary battery <NUM> and a traveling direction of the transfer device <NUM> are parallel to each other, may carried out subsequently to the top and bottom inspecting process (S30).

Specifically, the secondary battery <NUM> may rotate at an angle of <NUM> degrees in the first rotating process (S40), and this is to change to a state of the secondary battery <NUM> for a first side surface inspection.

A first side surface inspecting process (S50), in which a portion of a side surface of the secondary battery <NUM> is inspected by a first side surface inspecting machine <NUM>, may be carried out after the secondary battery <NUM> rotates at an angle of <NUM> degrees.

As the secondary battery <NUM> that is a cylindrical type has a side surface that is a curved shape, the first side surface inspecting machine <NUM> may be a device such as a 3D camera for efficient inspection.

A second rotating process (S60), in which the secondary battery <NUM> is rotated at an angle of <NUM> degrees by a second rotating machine <NUM> so that a top surface and a bottom surface of the secondary battery <NUM> are reversed, may be carried out after the first side surface inspecting process (S50).

In the second rotating process (S60), the secondary battery <NUM> in a lying state on a top surface of the transfer device <NUM> may rotate at the angle of <NUM> degrees and thus, a portion of the side surface, which is not inspected in the first side surface inspecting process (S50), may be prepared to be inspected.

A second side surface inspecting process (S70), in which the portion of the side surface of the secondary battery <NUM>, which is not inspected in the first side surface inspecting process (S50), is inspected by a second side surface inspecting machine <NUM>, may be carried out after the second rotating process (S60).

In the first side surface inspecting process (S50) and the second side surface inspecting process (S70), the side surface of the secondary battery <NUM> may be inspected for whether there are wrinkles, dents, scratches, rust, foreign matters, contaminant, discoloration, or the like, and whether other identifying phrases match a product. In addition, the secondary battery <NUM> may be inspected for defect through the inspection for swelling.

When the inspecting of the side surface of the secondary battery <NUM> is completed through the second side surface inspecting process (S70), the secondary battery <NUM> may be in a state in which all of the upper portion, the lower portion, and the side surface have been inspected.

Through the outer appearance inspection method according to the present invention, even the side surface of the cylindrical type secondary battery, which is a curved surface, may be efficiently inspected, and the entire outer appearance may be efficiently inspected during the process.

The outer appearance inspection method according to Embodiment <NUM> of the present invention may further include a discriminating process (S80) of discriminating the secondary battery <NUM> after the outer appearance inspection between a defective product and a good product on the basis of a result of each of the inspections.

Even an operation of separating the secondary battery <NUM>, which is defective, may be carried out during the inspection process and thus, efficiency of the process may be increased by the discriminating process (S80).

Claim 1:
An outer appearance inspection system (<NUM>) for inspecting an outer appearance of a secondary battery (<NUM>), the outer appearance inspection system (<NUM>) comprising:
a transfer device (<NUM>) configured to transfer the secondary battery (<NUM>) according to an inspection position;
a top and bottom inspecting device (<NUM>) disposed at a first inspection position (<NUM>) and configured to inspect an upper portion and a lower portion of the secondary battery (<NUM>);
a side surface inspecting device (<NUM>) disposed at a second inspection position (<NUM>) and configured to inspect a side surface of the secondary battery (<NUM>) for swelling; and
a rotating device (<NUM>) disposed at the second inspection position (<NUM>) and configured to rotate the secondary battery (<NUM>),
wherein the side surface inspecting device (<NUM>) inspects the side surface of the secondary battery (<NUM>) for swelling in a state in which the secondary battery (<NUM>) lies on the transfer device (<NUM>);
characterized in that the rotating device (<NUM>) comprises a first rotating machine (<NUM>) disposed at an entrance of the second inspection position (<NUM>) and configured to rotate the secondary battery (<NUM>) so that a longitudinal direction of the secondary battery (<NUM>) and a traveling direction of the transfer device (<NUM>) are parallel to each other, before the inspection at the second inspection position (<NUM>) is carried out.