A system for transporting and replacing batteries of electric vehicles

Abstract

The present invention relates to a battery transfer and replacement system comprising a device for aligning battery pallets using reference pins and reference holes. The system for transferring and replacing batteries of an electric vehicle according to the present invention comprises a mobile robot having a battery lift, a pallet alignment device installed on the mobile robot, a battery pallet installed on the pallet alignment device on which a battery is placed, and a pallet positioning device that determines the position of the battery pallet by emitting alignment light into the reference holes of the battery.

Description

Technology Field

[0001] The present invention relates to a system for transporting and replacing batteries of an electric vehicle, and more particularly to a battery transport and replacement system comprising a device for aligning battery pallets using reference pins and reference holes. Background Technology

[0002] Technologies for replacing and transporting batteries have been developed to address the issue of electric vehicle charging speeds. In particular, equipment for automatically replacing batteries using various methods has been continuously proposed from the early stages of mass-produced electric vehicle development to the present. For electric vehicle battery replacement, it is necessary to develop mechanisms for the removal, transport, and storage of batteries, as well as for the transport and assembly of rechargeable batteries.

[0003] Regarding battery removal, while the battery is detached via vertical movement from either the top or bottom depending on its location, no method is presented for connecting the battery to the vehicle that facilitates automatic detachment by means of a mechanism, nor is a specific method for disassembling the battery from the electric vehicle provided. Methods are proposed for transferring the removed battery to a charging and storage area via a conveyor or mobile robot. Fully charged batteries are also transferred from the charging and storage area via a conveyor or mobile robot, but automatic assembly by means of a mechanism or the assembly method itself is not specifically presented.

[0004] Korean Published Patent No. 10-2016-0143903 (Battery exchange device for electric vehicles and method for detaching and mounting batteries using the same) proposes a battery exchange device for electric vehicles that performs the detachment, transfer, and charging of a battery in a single step, comprising a transfer module that performs the function of transferring a battery through the side of a vehicle, a charging module that performs the function of charging a discharged battery, and a housing that supports the transfer module and the charging module, and further includes a lifting device that adjusts the height so that the transfer module and the battery mounting position coincide and forms an inclined surface to make the detachment and mounting of the battery faster and easier.

[0005] Korean Published Patent No. 10-2018-0025889 (Battery Exchange System) presents a battery exchange system having a battery lift that replaces a battery through the underside of a vehicle, the position of the lift being controlled by a type of mobile robot, and a mechanical lock structure for mechanically performing the assembly and disassembly of the battery and the vehicle.

[0006] However, most commercial electric vehicles currently on the market domestically and internationally find it difficult to automatically replace batteries using the proposed methods, as the vehicle design does not take automatic battery removal into account. Korean Published Patent No. 10-2016-0143903 does not provide specific fastening methods for battery fixation and disassembly, and Korean Published Patent No. 10-2018-0025889 can only be used if, in addition to the electric vehicle battery replacement device, a battery coupling device with the proposed mechanism is also applied to the vehicle.

[0007] In current electric vehicle production processes as well as in numerous previously proposed patents, the vehicle battery and the vehicle are accurately assembled using a standard pin-hole structure. Many patents, including Japanese Patent Publication No. 2011-168127 and Korean Patent Publication No. 10-013-0069112, propose a technology in which the battery slides into place through a pin-hole structure and an upper chamber of the pin. However, due to the heavy weight of both the battery and the vehicle, the implementation of such technologies requires a technique that allows the battery to be aligned relatively precisely through a separate method, or enables the position of the battery or the vehicle to be changed with minimal force to reduce the load on the pin.

[0008] Korean Published Patent No. 10-2013-0069112 proposes a technology that complements battery alignment using an elastic body, while Korean Published Patent No. 10-2018-0025889 proposes a technology that achieves load reduction during alignment by utilizing the battery shape instead of a reference pin to adopt a form similar to the chamber structure of a conventional reference pin, thereby allowing the battery lift to move freely in a planar motion. However, both prior art technologies achieve their objectives by modifying the vehicle's battery mounting structure, making them difficult to apply to general commercial electric vehicles.

[0009] Korean Published Patent No. 10-2018-0025889 proposes various methods for free horizontal movement. However, for the planar alignment of an electric vehicle battery, rotational motion is required in addition to horizontal movement, and even if a low-friction environment is realized, high force is required to accelerate a battery with high mass. Prior art literature

[0010] Korean Published Patent No. 10-2016-0143903, Korean Published Patent No. 10-2018-0025889, Japanese Published Patent No. 2011-168127, Korean Published Patent No. 10-013-0069112 The problem to be solved

[0011] One objective of the present invention is to provide an electric vehicle battery transfer and replacement system for battery replacement and transfer by considering the bolt fastening method currently used in commercial electric vehicles, rather than a conventional automated fastening device.

[0012] In addition, the present invention has another objective of assembling the battery and the vehicle by utilizing a reference pin-hole currently used for aligning the battery and the vehicle, but by adding a planar alignment device capable of electric horizontal and rotational movement that can move actively between the battery lift and the battery pallet to align the battery without the load of the reference pin and the alignment mechanism of the seating portion.

[0013] In addition, another objective of the present invention is to enable the alignment of the battery's hole with the reference pin on the pallet, which serves as the battery's landing point on the robot, when transferring batteries from general heavy-duty transfer equipment such as battery automated warehouses and forklifts using the same mechanism, thereby allowing for the immediate transfer of batteries without the need for separate equipment. means of solving the problem

[0014] The present invention, for solving the above-mentioned purpose, comprises a system for transporting and replacing a battery of an electric vehicle, wherein the system comprises a mobile robot having a battery lift, a pallet alignment device installed on the mobile robot, a battery pallet installed on the pallet alignment device and on which a battery is placed, and a pallet positioning device that determines the position of the battery pallet by emitting alignment light into a reference hole of the battery, wherein the pallet positioning device comprises a reference pin inserted into the reference hole of the battery, and the tip of the reference pin has a chamfer shape and has a slot having the same shape as the alignment light.

[0015] Preferably, the pallet positioning device further comprises a laser installed inside the reference pin that outputs alignment light coaxially with the reference pin to verify whether the reference pin and the reference hole are aligned, and a reference pin lifting unit that raises or lowers the reference pin. The pallet positioning device further comprises a reference pin extension to which the rear end of the reference pin is connected and which is raised or lowered by the reference pin lifting unit. The interior of the reference pin is treated with a low-reflection coating compared to the exterior.

[0016] Preferably, the pallet positioning device further comprises a reference pin transfer unit for adjusting the position of a reference pin. Effects of the invention

[0017] According to the present invention with the above-described configuration, electric vehicle batteries can be accurately loaded onto pallets for battery transport directly using a universal material handling device including a forklift without the need for separate equipment. Furthermore, a reference pin is used to determine the position of the battery and the vehicle body to determine the position of the pallet and the battery, and the load applied to the reference pin can be reduced by an active driving mechanism. In addition, unlike conventional technology, the present invention can be applied to battery replacement and transport equipment for battery replacement in the current structure without any design changes to the electric vehicle. Moreover, the present invention can be universally applied to various vehicle models and can avoid interference during screw fastening and disassembly at the edges of the battery. Brief explanation of the drawing

[0018] FIG. 1 is a configuration diagram of a system for transporting and replacing a battery of an electric vehicle according to one embodiment of the present invention. FIG. 2 is a side view showing the state in which a battery is mounted on the battery transfer and replacement system illustrated in FIG. 1. Figure 3 is a configuration diagram of the mobile robot shown in Figure 1. Figure 4 is a side view of the pallet alignment device shown in Figure 1. Figure 5 is a plan view of the pallet alignment device shown in Figure 1. Fig. 6 is a side view of the battery pallet shown in Fig. 1. FIG. 7 is a cross-sectional view of a pallet positioning device according to one embodiment of the present invention. FIG. 8 illustrates a state in which a reference pin is inserted into a reference hole of a battery according to one embodiment of the present invention. FIG. 9 is a detailed cross-sectional view of the pallet positioning device illustrated in FIG. 7. FIG. 10 illustrates the tip portion of a reference pin according to one embodiment of the present invention. FIG. 11 is a cross-sectional view of a reference pin according to one embodiment of the present invention. FIG. 12 is a detailed cross-sectional view of part A of the reference pin shown in FIG. 11. FIG. 13(a) illustrates a state in which a cross-shaped alignment light is displayed near a reference hole of a battery according to one embodiment of the present invention, and FIG. 13(b) explains a method for determining the position of a reference pin using the cross-shaped alignment light. FIG. 14 illustrates a reference pin transfer section in a battery transfer and replacement system according to another embodiment of the present invention. Specific details for implementing the invention

[0019] To fully understand the present invention, preferred embodiments of the invention are described with reference to the accompanying drawings. Embodiments of the present invention may be modified in various forms, and the scope of the present invention should not be interpreted as being limited to the embodiments described in detail below. These embodiments are provided to more completely explain the present invention to those with average knowledge in the art. Accordingly, the shapes of elements in the drawings may be exaggerated to emphasize clearer explanations. It should be noted that in each drawing, identical components may be depicted with the same reference numeral. Detailed descriptions of known functions and configurations that are deemed to unnecessarily obscure the essence of the present invention are omitted.

[0020] FIG. 1 is a configuration diagram of a system (100) for transporting and replacing a battery of an electric vehicle according to an embodiment of the present invention, and FIG. 2 is a side view showing a state in which a battery (202) is mounted on the battery transport and replacement system (100). As shown, the battery transport and replacement system (100) comprises a mobile robot (102) having a battery lift, a pallet alignment device (104) installed on the mobile robot (102), a battery pallet (106) installed on the pallet alignment device (104) on which a battery (202) is placed, and a pallet positioning device (108) that determines the position of the battery pallet (106) by emitting alignment light into a reference hole of the battery (202). The pallet positioning device (108) is installed on the battery pallet (106).

[0021] FIG. 3 is a configuration diagram of the mobile robot (102) illustrated in FIG. 1. As illustrated, a battery lift (302) is provided on the upper part. The mobile robot (102) transports a battery (202). The battery lift (302) raises or lowers the battery (202). A pallet alignment device (104) is attached to the battery lift (302).

[0022] FIG. 4 is a side view of the pallet alignment device (104) illustrated in FIG. 1, and FIG. 5 is a top view of the pallet alignment device (104) illustrated in FIG. 1. As illustrated, the pallet alignment device (104) is installed on a battery lift (302). The pallet alignment device (104) is equipped with a horizontal moving part (402) that moves the battery pallet (106) horizontally, and a rotary moving part (404) that moves the battery pallet (106) rotaryly.

[0023] A battery pallet (106) composed of battery seating portions (502, 504, 506, 508, 510, 512, 514, 516, 518, 520) is installed on the upper part of the pallet alignment device (104). The contact surface of the battery seating portions (502, 504, 506, 508, 510, 512, 514, 516, 518, 520) is formed of a plastic resin material that has lower hardness than the battery (202) and has an insulating function in order to stably seat the battery (202) and prevent damage to the battery (202). The battery mounting portions (502, 504, 506, 508, 510, 512, 514, 516, 518, 520) are positioned to avoid irregularities in the shape of the bottom surface of the battery (202) being transported. To enable the battery (202) to be moved sideways by the forks of a forklift and stacker crane used for moving heavy loads, the battery mounting portions (502, 504, 506, 508, 510, 512, 514, 516, 518, 520) are configured to avoid the entry path of the forks and are designed to have a height of 140 mm or more for smooth moving of the forks. The arrangement of the battery mounting portions (502, 504, 506, 508, 510, 512, 514, 516, 518, 520) must be positioned to avoid the edges of the battery, as most electric vehicles currently on the market are attached to the vehicle body via screws, in order to ensure smooth screw fastening and unfastening. The design of the battery mounting portions corresponding to multiple vehicle models can be derived by eliminating the space required for screw fastening and unfastening for each vehicle model, the volume of the uneven surface, the fork entry path, and the volume of the rotating part of the planar alignment mechanism from the total area.

[0024] Based on the derived volume, further reduction of the battery mounting portion can be considered to facilitate manufacturing. Since the position of the battery (202) on the mounting portion (502, 504, 506, 508, 510, 512, 514, 516, 518, 520) is always determined by the reference pin (702), deviations in the center of gravity depending on the battery loading situation can be ignored, but a design is required so that the center of gravity and the center of volume are located on the support area provided by the mounting portion (502, 504, 506, 508, 510, 512, 514, 516, 518, 520).

[0025] FIG. 6 is a side view of the battery pallet (106) illustrated in FIG. 1. As illustrated, a fork entryway (602) is provided between the battery mounting portions (502, 504, 506, 508, 510, 512, 514, 516, 518, 520).

[0026] FIG. 7 is a cross-sectional view of a pallet positioning device (108) according to one embodiment of the present invention. As shown, the pallet positioning device (108) is equipped with a reference pin (702), a laser (704), and a reference pin lifting unit (706, 708).

[0027] The reference pin (702) is configured to be inserted into the reference hole (712) of the battery (202). A laser (704) is installed inside the reference pin (702) and outputs alignment light coaxial with the reference pin (702) to allow verification of alignment between the reference pin (702) and the reference hole (712). The reference pin lifting unit is equipped with a reference pin lifting rail (706) and a reference pin lifting motor (708) to raise or lower the reference pin (702).

[0028] The pallet positioning device (108) may be equipped with a camera (710). By capturing the state in which alignment light is displayed near the reference hole (712) through the camera (710), a control signal for the pallet alignment device (104) for aligning the reference pin (702) and the reference hole (712) can be generated. The pallet alignment device (104) corrects the positional precision of the mobile robot (102) that is insufficient for coupling with the battery (202) and coupling with the vehicle of the reference pin (702).

[0029] FIG. 8 illustrates a state in which a reference pin (702) is inserted into a reference hole (712) of a battery (202) according to one embodiment of the present invention.

[0030] In order to fix the battery (202) to the correct position on the upper part of the pallet (106) and to assemble it accurately into the vehicle using the reference pin (702) used for fixing, the reference pin (702) must be inserted into the battery (202).

[0031] FIG. 9 is a detailed cross-sectional view of a pallet positioning device (108), and FIG. 10 shows the tip portion (1002) of a reference pin (702).

[0032] The tip portion (1002) of the reference pin (702) has a chamfered shape as illustrated and is provided with a slot (1004) of the same shape as the cross-shaped alignment light output from the laser (704). A screw hole (902) is formed on the side of the reference pin (702) to align and fix the laser (704) and the cross slit (1004) inside the reference pin (702). By fastening a set screw into the screw hole (902), the laser (704) is fixed to the reference pin (702) so that the cross-shaped alignment light generated by the laser (704) is not reflected from the inner surface of the reference pin (702) but is output through the slot (1004) of the tip portion (1002). A wire for supplying power to the laser (704) and controlling the laser (704) is installed through the laser wiring hole (904).

[0033] The pallet positioning device (108) may be equipped with a reference pin extension (906). The rear end of the reference pin (702) is connected to the front end of the reference pin extension (906), and the rear end of the reference pin extension (906) is connected to the reference pin lifting part (706, 708). The reference pin (702) is raised or lowered by the reference pin lifting part (706, 708) via the reference pin extension (906). Because the length required to function as a reference pin is shorter than the lifting height required for the reference pin (702), the reference pin (702) is extended by the reference pin extension (906). Since the reference pin (702) requires high hardness and machining precision, it needs to be short to lower the manufacturing cost, and the laser (704) must be positioned close to the tip (1002) of the reference pin (702) because the laser (704) being obscured by the narrow inner tube reduces not only the problem of reflected light but also the size of the laser pattern observable from the outside. It is also desirable for the reference pin (702) to be manufactured as short as possible to prevent the laser (704) from being installed in the deep hole of the reference pin (702).

[0034] FIG. 11 is a cross-sectional view of a reference pin according to one embodiment of the present invention, and FIG. 12 is a detailed cross-sectional view of part A of the reference pin shown in FIG. 11.

[0035] In this embodiment, a male screw (1202) is formed on the outer surface of the rear end of the reference pin (702), and a female screw (1106) is formed on the inner surface of the front end of the reference pin extension (906). A in FIG. 11 is the part where the rear end of the reference pin (702) and the front end of the reference pin extension (906) are joined. A step (1104) that determines the position of the reference pin extension (906) is formed on the outer surface of the rear end of the reference pin (702).

[0036] The inner surface (1102) of the reference pin (702) is treated to be low-reflection compared to the outer surface. This is to suppress laser light reflected from the inner surface (1102) from being output from the reference pin (702).

[0037] The pallet positioning device (108) is used to determine the alignment of the battery (202) and the vehicle body, and the position of the battery (202) and the pallet (106). Since the left-right (or lateral) spacing and height of the reference hole (712) used for battery alignment differ depending on the vehicle type, a pallet positioning device (108) must be provided separately for each vehicle type. The reference pin (702) must be able to move up and down to avoid interference when transferring the battery and loading batteries of other types.

[0038] To perform the lifting and lowering movement electrically, the pallet positioning device (108) is composed of a reference pin (702) and a linear actuator that drives the reference pin (702). The range of movement of the linear actuator is determined according to the required height of the reference pin (702). The method of loading the battery (202) onto the pallet (106) is determined by the reference pin (702), and the design ensures that the space required for screw operation on the edge of the battery for connection with the vehicle body does not overlap. In order to develop a pallet compatible with various vehicle models, the reference pin position must be selected so that the screw position for each battery does not overlap with each reference pin, and at this time, the position of the center of the battery must be selected so that it does not go excessively outside the seating area of ​​the battery seating part. The linear actuator driving the reference pin (702) can be implemented through various mechanisms such as a ball screw, a lead screw, or a timing belt pulley, but if the rigidity of the reference pin itself is insufficient, the reference pin (702) may easily become pinched against the vehicle body or battery, so a mechanism such as a linear motion guide that regulates linear motion must provide sufficient rigidity in other directions. The fixation of the reference pin (702) and the linear actuator may be directly connected, or the force acting on the reference pin may be measured through one or more load cells and used to smoothly connect with the battery and vehicle body through conformal control of the alignment mechanism.

[0039] The reference hole of the battery (202) and the vehicle is aligned using a pallet positioning device (108), and the position of the battery (202) on the pallet (106) is determined. The alignment state is measured using a camera (710) to align the reference pin (702) and the reference hole (712) of the battery (202) through a pallet alignment device (104). In the case of recognition through the camera (710), there is a problem of reduced recognition rate because the condition of the bottom of the battery (202) is not uniform due to damage or contamination during vehicle operation. To compensate for this, the position of the reference pin (702) is marked on the bottom of the battery (202) through a cross-light laser (704) coaxial with the reference pin (702) inside the reference pin (702) even before the reference pin (702) approaches, thereby enabling the alignment state with the reference hole (712) to be obtained through an image with high contrast. The tip (702) of the reference pin (702) has a chamfered shape and a cross-shaped slot (1004) is formed so that laser light can pass through. The interior of the reference pin (702), including the part where the laser (704) is inserted, is coated with an anti-reflective paint to prevent the cross light from being reflected out. In order to adjust the size of the cross light without replacing the laser lens, the laser mounting part inside the reference pin (702) is machined with sufficient clearance to change the laser position. The laser (704) is fixed to the reference pin (702) by a set screw (not shown) that is fastened to a screw hole (902).

[0040] Even though there is an active alignment mechanism to reduce the load on the reference pin (702), considering cases where the surface of the reference pin (702) is damaged due to damage between joints or accidental damage, or where excessive deformation occurs on the reference pin (702), it has a shape that is easy to process through sewing to facilitate replacement and processing. The female screw fixing pin is joined to the fixing block by machining a male screw, and has a positioning step to determine the joining depth. It has a shape that has a machining groove to form a step, facilitate screw machining, and avoid interference during joining.

[0041] FIG. 13(a) illustrates a state in which a cross-shaped alignment light (1302) is displayed near a reference hole (712) of a battery (202) according to one embodiment of the present invention, and FIG. 13(b) explains a method for determining the position of a reference pin (702) using the cross-shaped alignment light (1302).

[0042] When the reference pin (702) and the reference hole (712) are aligned to some extent, the center of the alignment light (1302) passes through the reference hole (712), so alignment cannot be performed using the center of the alignment light (1302). Therefore, in this embodiment, a cross-shaped alignment light (1302) in which two straight lines intersect is used. It is preferable that one straight line has a length of at least twice the diameter of the reference hole (712). When the alignment light (1302) is displayed near the reference hole (712) as in FIG. 13(a), the alignment light (1302) is extended as in FIG. 13(b), and the point (P) where it intersects is determined as the horizontal position of the reference pin (702). It is sufficient for the alignment light (1302) to be in the form of at least two intersecting straight lines, and the two straight lines do not necessarily need to intersect perpendicularly.

[0043] The position of the reference pin (702) appears around the reference hole (712) by a cross laser (704) installed coaxially inside the reference pin (702), making it possible to check whether the reference hole (712) and the reference pin (702) are aligned. Because it is a cross or pattern laser, unlike a general point laser, laser reflections can be seen around the reference hole (712), allowing the alignment of the reference hole (712) and the reference pin (702) to be checked. The laser (704) is installed inside the reference pin (702) because it must also be used for alignment between the battery (202) and the vehicle (not shown) after the battery (202) is fixed to the reference pin (702).

[0044] FIG. 14 is a plan view illustrating a reference pin transfer section (1402) in a battery transfer and replacement system (1400) according to another embodiment of the present invention. In FIG. 14, "L" indicates the left side, "R" indicates the right side, "F" indicates the front side, and "B" indicates the rear side.

[0045] Depending on the type of battery, the spacing between the left reference hole and the right reference hole is different. Therefore, in order to use the battery transfer and replacement system (1400) with various types of batteries, a mechanism for adjusting the left-right spacing (Dp) of the reference pin (702) is required. The reference pin transfer unit (1402) adjusts the position of the reference pin (702). The reference pin transfer unit (1402) can be implemented as a rotary joint.

[0046] The embodiments of the present invention described above are merely illustrative, and those skilled in the art will readily understand that various modifications and equivalent alternative embodiments are possible therefrom. Therefore, it will be understood that the present invention is not limited only to the forms mentioned in the detailed description above. Accordingly, the true technical scope of protection of the present invention should be determined by the technical spirit of the appended claims. Furthermore, the present invention should be understood to include all modifications, equivalents, and substitutions within the spirit and scope of the present invention as defined by the appended claims.

Claims

Claim 1 A battery transfer and replacement system for an electric vehicle, comprising: a mobile robot having a battery lift; a pallet alignment device installed on the mobile robot; a battery pallet installed on the pallet alignment device and on which a battery is placed; and a pallet positioning device that emits alignment light into a reference hole of the battery to determine the position of the battery pallet, wherein the pallet positioning device comprises a reference pin inserted into the reference hole of the battery, and the tip of the reference pin has a chamfer shape and has a slot of the same shape as the alignment light. Claim 2 A battery transfer and replacement system according to claim 1, wherein the pallet positioning device further comprises a laser installed inside the reference pin to output the alignment light coaxially with the reference pin to enable verification of alignment between the reference pin and the reference hole, and a reference pin lifting unit for raising or lowering the reference pin. Claim 3 A battery transfer and replacement system according to paragraph 2, wherein the pallet positioning device further comprises a reference pin extension that is connected to the rear end of the reference pin and raised or lowered by the reference pin lifting part. Claim 4 A battery transfer and replacement system according to claim 1, wherein the pallet positioning device further comprises a reference pin transfer unit for adjusting the position of a reference pin.

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