Railway vehicle running with cylindrical wheels

Abstract

The railway vehicle according to the present invention uses cylindrical running wheels having smooth outer circumferential surfaces to fundamentally remove hunting oscillation, and is configured such that the left and the right running wheel thereof independently rotate to enable smooth active running even in a curved section. In addition, according to the present invention, a one-axis bogie including safety wheels in contact with rail inner surfaces and a bogie rotation center is configured as a basic module. Therefore, hunting oscillation of the railway vehicle is reduced, the railway vehicle does not derail, and the noise due to friction with a rail even in a curved section is significantly reduced, so that the railway vehicle runs stably.

Description

Railroad vehicle running on cylindrical wheels

[0001] The present invention relates to a railway vehicle that runs on cylindrical wheels. More specifically, the invention relates to a railway vehicle having a bogie of a new structure that prevents hunting oscillation, which is a fundamental problem of existing conical wheels, by separating the function of supporting the vertical load of the railway vehicle and the function of guiding lateral movement into separate wheels, and by using a cylindrical driving wheel with a flat outer surface that rotates independently on the left and right sides as the wheel that supports the vertical load and runs.

[0002] Furthermore, the present invention relates to the field of railway vehicle technology utilizing cylindrical wheels, which overcomes the limitations of the conventional 'manual driving' method that relies entirely on external mechanical track switches and provides a mechanical basis for 'active driving' in which the vehicle itself selects a path and controls its driving direction. In particular, the present invention relates to a core hardware technology for a new railway system capable of active curve steering and direction control to perform active driving, going beyond simple prevention of hunting motion, by providing a bogie structure that enables active control of rotational speed by combining power units with driving wheels that rotate independently on the left and right sides.

[0003] Railways have served as a core means of transportation for humanity for over 200 years. However, despite this long history, the wheel-rail relationship, which is the most fundamental aspect of the railway system, has not achieved fundamental technological innovation, as it has maintained the structure of an integral conical wheel—which prevents derailment from the rail—almost unchanged to this day.

[0004] The integrated conical wheel is a structure in which two conical wheels are fixed to a single axis of rotation and always rotate together. Thanks to the geometric shape of the inclined conical surface, this structure provides a centering function that prevents derailment without a separate steering device. However, this centering function has two serious inherent limitations.

[0005] First, the phenomenon of hunting motion inevitably occurs. The center-restoring function causes the wheels to repeatedly deviate from the center to the opposite side and then return, resulting in the formation of an unstable S-shaped trajectory. As speed increases, this hunting motion induces violent vibration and noise, worsening ride comfort, limiting high-speed driving, and causing serious damage to the wheels and rails. The heavy bogies, bolsters, and complex suspension units used to address this have caused other problems, such as increased costs and impaired cornering performance.

[0006] Second, it became the fundamental cause of trapping the railway system in a 'manual driving' paradigm that relies entirely on external facilities for direction changes. Since vehicles lack the ability to change direction on their own, route changes must rely on external mechanical switches (turnouts) that open the rails. This forces centralized operation, controlling all train movements through a central control system, and has acted as a primary cause severely hindering the flexibility and efficiency of the entire system.

[0007] Meanwhile, Independent Rotating Wheels (IRW) technology was developed to lower the floor height of low-floor trams by removing the axle, allowing the left and right wheels to rotate independently. However, to retain the derailment prevention function of integrated conical wheels, this technology merely electronically synchronizes the rotation of mechanically separated conical wheels, effectively causing the left and right wheels to rotate at the same speed. In other words, IRW technology is designed solely to lower the vehicle floor and fails to resolve the hunting motion issues of integrated conical wheels; it is a technology that has not overcome the limitations of 'manual driving' that still relies on external switches.

[0008] In addition, there are cases where the driving wheel supporting the vertical load and the horizontal guide wheel guiding the lateral direction are separated in some track devices used in amusement rides, but this is for the special purpose of operating a simple loop line without track switches. It is impossible to apply the structure of the horizontal guide wheel to general railway systems that must support heavy weights while passing through complex switch sections, and the technical concept, purpose, and configuration are all fundamentally different from the present invention.

[0009] Therefore, there is an urgent need for fundamentally new railway vehicle bogie technology that can simultaneously overcome the dual limitations of hunting motion and manual driving caused by 200-year-old conical wheel technology.

[0010] The present invention has been devised to solve the problems of the prior art as described above, and the problem to be solved is as follows.

[0011] The first task is to provide a fundamental mechanical foundation for implementing 'active driving,' which enables railway vehicles to autonomously select a route and control their direction of travel without external assistance, thereby overcoming the limitations of 'manual driving' that relies on external mechanical switches.

[0012] The second task is to secure specific means to achieve the first task, thereby fundamentally eliminating the hunting motion—a chronic problem of existing conical wheels—and ensuring stable driving performance free from vibration and noise even during high-speed driving.

[0013] The third task is to provide a new structure of a single-axle bogie that includes a safety wheel and a bogie rotation center that prevents the bogie from deviating from the left and right inner sides of the rail, so as to reliably prevent derailment under any driving conditions.

[0014] The fourth task is to provide an expandable bogie system that can be applied to various types of vehicles, such as freight train 2-axle bogies, passenger train 2-axle bogies, and heavy-duty 3-axle bogies, using a 1-axle bogie as the basic module.

[0015] The fifth task is to improve the overall operational economic efficiency of the railway system by providing a wear dispersion device that prevents wear on specific parts of cylindrical running wheels, thereby extending the lifespan of parts and reducing maintenance costs.

[0016] The present invention, designed to solve the aforementioned problems, is centered on devising a new wheel system for railway vehicles and extending it to suit various vehicle types.

[0017] First, the bogie of the present invention provides a mechanical structure capable of connecting power units to each of the left and right independent driving wheels so that they rotate independently. Through this, a foundation is secured to implement 'active driving,' in which the vehicle changes direction on its own, by actively creating a difference in the rotational speeds of the left and right driving wheels.

[0018] Second, the present invention clearly separates the functions of the wheels of a railway vehicle into driving wheels that support a vertical load and safety wheels that restrict lateral movement. The driving wheels are manufactured in a cylindrical shape with a flat outer surface to eliminate the root cause of hunting motion, and the left and right wheels rotate independently to smoothly pass through curved sections with different travel distances.

[0019] Third, the single-axle bogie, which includes a cylindrical driving wheel and a safety wheel, is equipped with a bogie rotation center capable of horizontal rotation relative to the car body. This bogie rotation center allows the entire bogie to rotate smoothly when the safety wheel guides the driving direction along the inner surface of the rail in a curved section, and mechanically prevents derailment by the safety wheel interacting with the inner surfaces of both rails so that the bogie does not deviate from the left and right inner surfaces of the rail under any conditions.

[0020] Fourth, it provides expandability applicable to various types of vehicles using a single-axle bogie as the basic module. For freight trains transporting heavy loads, a freight two-axle bogie is configured by connecting two single-axle bogies in the center, or a three-axle bogie is configured by combining two single-axle bogies with a fixed bogie, and for passenger trains requiring fast and stable operation, an articulated two-axle bogie is configured by connecting two adjacent vehicles.

[0021] Fifth, to extend the lifespan of the cylindrical running wheel, a wear dispersion device is provided that actively moves the horizontal position of the safety wheel. This device evenly distributes the contact surface between the cylindrical running wheel and the rail.

[0022] A railway vehicle running on cylindrical wheels according to the present invention can overcome the fundamental limitations of the prior art and provide the following useful effects.

[0023] First, the bogie structure of the present invention provides a mechanical basis for differentiating the rotational speeds of left and right cylindrical driving wheels by combining power units to each wheel, thereby moving away from 'manual driving,' where the railway system relies on equipment that opens the direction of the rail from the outside, and providing a technical basis for a new 'active driving railway' in which the vehicle itself determines the path and drives.

[0024] Second, by using cylindrical running wheels with flat outer surfaces, the hunting motion that inevitably occurs in conical wheel structures can be fundamentally eliminated. Consequently, vibration and noise generated by railway vehicles are significantly reduced even during high-speed operation, thereby improving driving stability, enhancing passenger comfort, and resolving complaints from residents near the railway.

[0025] Third, safety wheels provided separately from the driving wheels work in conjunction with the bogie's center of rotation to guide the horizontal rotation of the bogie in the direction of travel in curved sections, and mechanically restrain lateral movement so that it never deviates from the inner sides of the rails, thereby strongly preventing derailment even in emergency situations such as external impact or sudden braking, and increasing the safety of railway operation.

[0026] Fourth, the single-axle bogie of the present invention can be applied in various forms as a basic module. This provides versatility, allowing for the configuration of various bogies suitable for railway vehicles with different purposes, such as freight two-axle bogies for general freight trains, passenger two-axle bogies for high-speed passenger trains, and three-axle bogies required for transporting very heavy loads like locomotives or torpedo cars.

[0027] Fifth, the elimination of severe vibrations caused by meandering motion and friction in curved sections, along with the ability to use the contact surface of the running wheels evenly through wear dispersion devices, contributes to extending the lifespan of wheels and rails and reducing maintenance costs. Additionally, by reducing the curve radius of newly constructed railways, it allows for economical passage over private land or obstacles, thereby reducing construction costs and improving the overall economic efficiency of the railway system.

[0028] FIG. 1 is a perspective view showing the overall structure of a single-axle bogie according to the present invention.

[0029] FIG. 2 is an exploded perspective view to clearly show the components and coupling relationships of a single-axle bogie according to the present invention.

[0030] FIG. 3 is a plan view of a single-axle bogie according to the present invention.

[0031] FIG. 4 is a side view (a) and a perspective view (b) showing the detailed structure of a safety wheel included in a single-axle bogie according to the present invention.

[0032] FIG. 5 is a perspective view of a wheel set, which is a core component of a single-axle bogie according to the present invention.

[0033] FIG. 6 is a front view showing the configuration of a wear dispersion device included in a wheel set.

[0034] Figure 7 is a plan view showing the configuration of a wear dispersion device.

[0035] FIG. 8 is a perspective view showing two single-axle bogies side by side to show the basic configuration of a two-axle bogie.

[0036] FIG. 9 is a perspective view of a two-axle bogie for a freight train constructed using two one-axle bogies according to the present invention.

[0037] FIG. 10 is a perspective view of an articulated two-axle bogie for a passenger train constructed using two single-axle bogies according to the present invention.

[0038] FIG. 11 is a perspective view (a) and a side view (b) of a three-axle bogie configured by combining two single-axle bogies and a fixed bogie according to the present invention.

[0039] FIG. 12 is a perspective view of an integrated conical wheel according to the prior art.

[0040] FIG. 13 is a diagram showing a comparison between the meandering driving trajectory (a) of the prior art and the stable straight driving trajectory (b) of the present invention.

[0041] For a detailed description, refer to 'Forms for carrying out the invention'.

[0042] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted in advance that the present invention is not limited to the described embodiments and that various modifications are possible without departing from the essence of the invention as claimed in the claims.

[0043] Railway vehicles running on integrated conical wheels have wheels and rails made of high-strength steel, so they have less than one-third of the driving resistance compared to cars using rubber wheels and can transport heavy cargo. Although they have been used unchanged for 200 years, they have problems with hunting and manual driving.

[0044] The integrated conical wheel used in conventional railway vehicles has a structure in which two conical wheels (410) are combined on a single conical wheel rotation axis (440), as shown in FIG. 12. This structure prevents derailment by using a conical running surface (430) and a flange (420) while the two conical wheels always rotate together, but it inevitably causes hunting motion, leading to various problems such as vibration, noise, and reduced ride comfort. The present invention is intended to solve the problem of the hunting trajectory of the conventional technology shown in FIG. 13 (a) and to ensure driving with the hunting motion eliminated as shown in (b). FIG. 13 is a reference diagram to explain the hunting motion of the conventional technology and is not a diagram to explain the new technology.

[0045] The present invention devised a railway vehicle that runs on cylindrical wheels to solve the problems of such existing railway vehicles. FIG. 1 is a perspective view showing the overall structure of a single-axle bogie according to the present invention, FIG. 2 is an exploded perspective view to clearly show the components and coupling relationships of the single-axle bogie according to the present invention, FIG. 3 is a plan view of the single-axle bogie according to the present invention, and FIG. 5 is a perspective view of a wheel set, which is a core component of the single-axle bogie according to the present invention.

[0046] FIGS. 1 to 3 show a single-axle bogie (300), which is a core element of the present invention. The single-axle bogie (300) is a basic unit that secures safe driving characteristics of a railway vehicle without hunting motion. As can be understood from FIGS. 1, 2, and 5, the single-axle bogie (300) is largely composed of a wheel set (100) that is in direct contact with the rail and is responsible for driving, and a wheel bogie (310) that supports the wheel set (100) and is connected to the vehicle body.

[0047] The wheel bogie (310) is a frame that supports the axle bogie (300), and is a strong structure that connects the driving wheels and the vehicle body by connecting two insertion support members (320) placed in the transverse direction, two rotation center support members (340), and four suspension unit support members (360) in the longitudinal direction. The rotation center support members (340) are combined with the bogie rotation center (350) so that the axle bogie (300) connects to the vehicle body and simultaneously performs load transfer and rotation. Two bogie insertion openings (330) are installed at each end of the insertion support members (320), connecting the wheel bogie (310) and the wheel set (100) in a state where only vertical movement is possible. The connection and role of these will be explained in detail later.

[0048] FIG. 5 shows the detailed structure of a wheel set (100), which comprises a non-suspension mass (unspringed mass) that directly receives vibrations occurring between the rail (500) and the running wheel (110) in a railway vehicle.

[0049] The core of the wheel set (100) is a driving wheel (110) that contacts the upper surface of the rail (500). The outer surface of the driving wheel (110) is formed as a flat cylindrical driving surface (111), and the left and right driving wheels rotate independently of each other through their respective driving wheel axles (120). Since the cylindrical driving surface (111) has an inclination of “0,” the period of the serpentine motion geometrically becomes infinite, so no serpentine motion occurs.

[0050] The driving wheel (110), which travels by contacting the upper surface of the rail (500) in the wheel set (100) and transmitting a vertical load, is configured so that the left driving wheel and the right driving wheel rotate separately. In order to configure the driving wheel (110) that rotates independently, the present specification describes an embodiment in which one driving wheel axle (120) and one driving wheel (110) are combined to rotate together, and the driving wheel (110) is supported by a wheel support unit (130) having a bearing box, and the driving wheel (110) is configured to be separated on both sides and rotate separately.

[0051] Additionally, the 1-axle bogie (300) of FIG. 3 shows the arrangement of four safety wheels (210) to prevent the driving wheel (110) from derailing. These four safety wheels (210) support the driving wheel (110) so that it does not move left or right or rotate and move outward between the left and right inner sides of the rail (500), thereby mechanically restraining the driving wheel (110) so that it does not derail from the track.

[0052] As illustrated in detail in FIG. 4, the safety wheel (210) is manufactured in the form of a conical rotating body having a safety wheel conical surface (211) inclined with respect to a central axis. This structure allows the safety wheel (210) to effectively pass through the narrow space (about 40 mm) of the turnout, and reduces noise and wear by reducing vertical friction with the inner surface of the rail (500). Furthermore, even if the safety wheel comes into contact with the nose portion of the turnout, the safety wheel, which is composed of a conical rotating body and has a wide front surface in the direction of travel, pushes the nose away with the safety wheel conical surface (211) to prevent collision.

[0053] A wheel support unit (130) supports the driving wheel axle (120), and an elastic member (150) that transmits the vertical load of the railway vehicle and mitigates vibration is installed on the upper part of the wheel support unit (130). A damper (not shown) that absorbs elastic energy stored in the elastic member (150) and reduces vibration transmitted to the railway vehicle is placed between the wheel support unit (130) and the suspension unit support (360) of the wheel bogie (310). Although the damper is not shown in the drawing, it is a configuration that can be understood by a person skilled in the art.

[0054] The wheels of a railway vehicle are classified into power wheels, which are equipped with a motor to transmit rotational and braking forces along with driving, and traction wheels, which do not have a motor and only perform driving and braking. In this embodiment, the explanation is based on the power wheels. In the power wheels, the driving wheel axle (120) protrudes toward the inner wheel support unit (130) and rotates. A rotary gear box (180) is installed on the driving wheel axle (120) that protrudes in this way, and a driving motor is connected to the driving motor connection part (190) attached to the rotary gear box (180) so that rotational force is transmitted.

[0055] The driving motor connection part (190) is configured as a coupling device that adjusts the deviation between a driving motor located on a wheel bogie (310) that is supported by an elastic member (150) and a rotating gear box (180) located on a vibrating wheel set (100) and a driving motor located on a wheel bogie (310) that reduces vibration.

[0056] As shown in FIG. 5, the wheel set (100) is composed of two wheel units positioned on the left and right sides. The configuration of these wheel units is formed by connecting two wheel support units (130) that support the driving wheel axle (120) on the left and right sides of the driving wheel (110) and two horizontal support units (140). The horizontal support units (140) that constitute the wheel units perform two additional important functions. One of these functions is to support two safety wheels (210) at the front and rear of the driving wheel (110) by accommodating the horizontal support member (231) of the safety wheel support (230) that supports the safety wheel (210), and the other function is to support the bogie insertion rod (160) that is installed and connected to the wheel bogie (310). These functions will be explained again later using the relevant drawings.

[0057] The wheel set (100), which is composed of two wheel units on the left and right, is coupled to the wheel bogie so that four safety wheels (210) support the inner surface of the rail (500), thereby restraining a pair of driving wheels (110) from moving sideways and allowing them to drive. A pair of driving wheels (110) travels safely along the rail (500) without derailing due to these four safety wheels (210).

[0058] The safety wheel (210) is constrained from lateral movement by the inner side of the rail (500) so that the driving wheel (110) does not move sideways and derail from the rail (500), thereby ensuring the safety of the railway vehicle. Since the clearance space on the inner side of the rail at the nose portion of the existing rail turnout where the rails intersect is only about 40 mm, the safety wheel must be configured to operate smoothly while passing through the turnout within the clearance space of this turnout.

[0059] The safety wheel (210) that prevents derailment by utilizing the left and right inner sides of the rail (500) can be configured to be installed as a vertical safety wheel or a horizontal safety wheel so as to move at the same speed as the driving wheel (110) and come into contact with the inner side of the rail (500). The vertical safety wheel is configured to be set vertically like the driving wheel so that the side of the wheel comes into contact with the inner side of the rail, and the horizontal safety wheel is configured so that the wheel lies horizontally and rotates so that the driving surface of the wheel comes into contact with the inner side of the rail.

[0060] Although the vertical safety wheel can pass through the 40mm horizontal clearance provided by the turnout, as the railway vehicle travels, vertical friction occurs between the inner surface of the rail (500) and the vertical safety wheel, causing noise and wear. In addition, a vulnerable structure is formed where the nose part protruding from the turnout and the vertical safety wheel collide directly, which threatens the safety of the railway vehicle.

[0061] Meanwhile, although the horizontal safety wheel does not generate friction with the inner surface of the rail because the running surface of the safety wheel contacts the side of the rail, there is a problem that the horizontal safety wheel, which is accommodated by the 40mm horizontal clearance of the turnout, cannot support the horizontal load of the railway vehicle.

[0062] In order to solve this problem, the safety wheel (210) is formed in a conical shape having a central axis and a safety wheel conical surface (211) having an inclination, and is supported by a safety wheel axle (220) that rotates with the same inclination and a bearing, thereby sufficiently supporting the horizontal load of the railway vehicle, and is configured so that the outer surface of the safety wheel contacts the inner surface of the rail without causing vertical friction.

[0063] If the conical rotating body of this embodiment, with an inclination of 60 degrees, is configured to contact the rail side at a depth of 40 mm, the horizontal gap required for a contact depth of 40 mm is approximately 23.1 mm. Since a horizontal distance of 28.1 mm is required by adding a reinforcement thickness of 5 mm, it can sufficiently pass through a turnout with a horizontal passage space of 40 mm or more. The inclination and diameter of the safety wheel conical rotating body can be appropriately used depending on the horizontal load being supported, the speed of the railway vehicle, and the required contact depth between the conical surface and the rail side.

[0064] In this embodiment, a conical rotating body with a 60-degree inclination and a diameter of 200 mm is used for description. However, depending on the speed or load of the railway vehicle or the minimum turning radius of the rail, it is preferable to configure the safety wheel with a conical rotating body with an inclination between 45 and 75 degrees and a diameter of 150 mm or more so that the safety wheel axle is installed on the upper surface of the rail.

[0065] FIG. 4 is a drawing showing the detailed structure of a safety wheel (210) included in a 1-axle bogie (300), where (a) is a side view and (b) is a perspective view. It shows a safety wheel unit including a safety wheel (210), wherein the safety wheel support (230) is composed of a support inclined member (232) that supports the safety wheel axle (220), which is the center of the safety wheel (210), and a support horizontal member (231) to which a horizontal screw unit (250) that moves the safety wheel (210) horizontally is coupled. The support horizontal member (231) moves inside the horizontal support unit (140) according to the rotation of the horizontal screw connecting rod (260) connected to the coupled horizontal screw unit (250), and the connected safety wheel (210) moves left and right. The horizontal screw unit (250) and the horizontal screw connecting rod (260) are connected to each other by a horizontal screw, so that the horizontal screw unit (250) moves horizontally by the rotation of the horizontal screw connecting rod (260). To allow the horizontal support member (231) to move smoothly horizontally through the passage inside the horizontal support unit (140), horizontal connecting wheels (240) are installed on three sides of the horizontal support member (231): the left side, the right side, and the top side.

[0066] A wear dispersion device is installed on the 1-axle bogie (300) to uniformly disperse the wear surface formed as the driving wheel (110) travels along the rail on the cylindrical outer surface. The wear dispersion device is a device that continuously disperses the position of the driving wheel (110) in contact with the rail (500) by moving the safety wheel (210) horizontally little by little, and the device is configured to continuously move the safety wheel, which determines the horizontal position of the driving wheel (110), left and right. A horizontal screw connecting rod (260) connecting two safety wheels (210) facing the inner surface of the rail (500) and the two horizontal screw connecting rods (260) are connected to a single horizontal screw rotation unit (270) so that four safety wheels always move horizontally in the same direction and the same distance, and the horizontal screw rotation unit (270) is operated and controlled using a separate rotation device. In this embodiment, a worm gear is used to simultaneously transmit rotation between the horizontal screw connecting rod (260) and the horizontal screw rotation unit (270), but this method of transmitting rotation can be configured in various ways.

[0067] In the present invention, the wheel set (100) is the most important element responsible for the operation of the railway vehicle. The driving wheel (110) of the wheel set (100) not only completely eliminates the hunting motion of the railway vehicle, but can also change the direction of travel of the wheel set (100) by utilizing the difference in driving distance of the driving wheel. One driving wheel (110), which has a longer driving distance due to a faster rotational speed, moves ahead, creating horizontal rotation of the left and right driving wheels (110), thereby changing the direction of travel of the wheel set (100). Active driving is the railway vehicle determining its own direction of travel and driving by controlling the direction of the 1-axle bogie using the difference in driving distance of the left and right wheels that rotate independently.

[0068] The 1-axle bogie (300) is configured by combining a wheel set (100) and a wheel bogie (310), and since the driving direction rotates around the bogie rotation center (350) supported by the rotation center support (340) of the wheel bogie (310), the 1-axle bogie (300) can travel flexibly even on curved rails, always aligning the direction of travel of the driving wheel (110) with the direction of the rail (500), thereby completely eliminating the occurrence of an attack angle created by the existing integrated conical wheel on curved rails and allowing it to travel smoothly on sharp curved rails with a radius of 20m without friction or noise. In this process, four safety wheels (210) operate to support the inner surface of the rail so that it can pass through the curved section smoothly without derailing.

[0069] In order for the bogie (300) to effectively perform a change of direction, the bogie rotation center (350) has a vertical rotation axis and is positioned to be orthogonal to the common horizontal center axis formed by a pair of driving wheel axles (120). When the vertical rotation axis of the bogie rotation center (350) and the horizontal center axis of the driving wheel axles (120) are orthogonal, the force generated by the difference in driving distance of the driving wheels (110) is all converted into the rotational moment of the bogie (300). Therefore, when driving in a curved section, no force is generated that is dispersed throughout the bogie (300), so it does not shake and only the rotational moment remains, allowing it to rotate stably.

[0070] In a single-axle bogie (300) in which no hunting motion occurs and vibration is reduced, the connection between the wheel set (100) constituting the non-suspension mass and the wheel bogie (310) holding the wheel set consists of a vertical connection unit that accommodates only vertical degrees of freedom and a suspension unit that reduces vertical vibration.

[0071] To this end, the 1-axle bogie (300) is configured to include a vertical connection unit that allows only vertical movement between two members between the wheel bogie (310) and the wheel set (100), and a suspension unit that absorbs a certain portion of vibration transmitted from the rail to the railway vehicle between the wheel bogie (310) and the wheel set (100).

[0072] The vertical connection unit installed in the wheel set (100) is composed of a bogie insertion opening (330) installed in the wheel bogie (310) and a bogie insertion rod (160) installed in the wheel set (100), and the bogie insertion rod (160) inserted into the bogie insertion opening (330) is configured to move freely in the vertical direction but is constrained in other directions to transmit horizontal load and moment between the wheel bogie (310) and the wheel set (100).

[0073] Here, the configuration of the trolley insertion rod (160) having a square face includes a vertical connecting wheel (170) installed on the square face of the trolley insertion rod (160) and rotating to transmit the horizontal load of the wheel set (100) to the trolley insertion port (330), and the trolley insertion port (330) is installed on the insertion port support (320) which forms the main frame of the wheel trolley (310) and transmits the horizontal load and moment transmitted by the trolley insertion rod (160) to the wheel trolley (310).

[0074] Additionally, the suspension unit is composed of an elastic member (150) and a damper installed between the wheel bogie (310) and the wheel set (100). The elastic member (150), such as a spring, accommodates vertical movement and uses the generated elastic force to transmit the vertical load of the railway vehicle to the driving wheels. The damper is a device that absorbs the elastic energy stored in the elastic member. This suspension unit blocks shocks transmitted to the railway vehicle and absorbs vibrations to improve the ride comfort of the railway vehicle.

[0075] A single-axle bogie (300) that combines a wheel set (100) consisting of a driving wheel (110) and a safety wheel (210) with a wheel bogie (310) has no functional problems even when directly connected to the car body using the bogie rotation center (350). Therefore, when a railway vehicle with a single-axle bogie (300) directly connected to the car body is used in a railway vehicle for passenger transport, such as an urban railway, it has an economic effect compared to a conventional two-axle bogie with integrated conical wheels.

[0076] Referring to FIG. 3, the process of an axle bogie (300) actively driving on a curved rail by controlling the rotational speed of the left and right driving wheels is explained as follows: it includes a driving wheel axle (120) that rotates together with one driving wheel (110) separated into left and right, a rotating gear box (180) that transmits rotational force to the driving wheel axle (120), and a driving means that transmits rotational force to the rotating gear box (180). The driving means includes a rotating motor (not shown) and a motor control unit (not shown) that controls the rotational speed of the rotating motor. By connecting one rotating motor to one driving wheel (110) and adjusting the rotational speeds of the left and right rotating motors using the motor control unit, active driving is performed to control the direction of travel of the driving wheels. As such, active driving is realized by independently driving rotary motors and gearboxes connected to the left and right driving wheel axles (120), and by receiving control signals from the motor control unit to change the left and right rotation speeds. Although the rotary motors and the motor control unit are not shown in the drawing, the configuration is easily understood by a person skilled in the art.

[0077] When active driving is performed with the 1-axle bogie (300), the driving wheels (110) proactively take the curved direction of the rail (500) on their own and drive, so there is no contact or friction between the rail (500) and the safety wheels (210), thereby completely eliminating noise and wear caused by the safety wheels. The 1-axle bogie (300) equipped with a driving motor changes direction around the bogie rotation center (350), and by controlling the rotational speeds of the two left and right driving wheels (110) with their respective driving motors, the 1-axle bogie (300) can perform active driving that smoothly changes direction to match the curve of the rail (500).

[0078] Even if a situation occurs where active driving is not achieved due to sudden braking in an emergency, causing the driving wheels to slip, or due to a malfunction of the driving motor, the four safety wheels support the inner surface of the rail, so the railway vehicle does not derail and continues to drive, thereby ensuring active driving that always guarantees the safety of the railway vehicle.

[0079] The 1-axle bogie (300) of the present invention is a basic module and has versatility that allows it to be expanded and applied to meet the requirements of various vehicle types. FIG. 8 is a perspective view showing two 1-axle bogies side by side to show the basic configuration of a 2-axle bogie, and FIG. 9 is a perspective view of a 2-axle bogie for a freight train configured using two 1-axle bogies (300). As shown in FIG. 8, two 1-axle bogies (300) placed on a rail (500) each having a driving wheel (110) and a safety wheel (210) can rotate independently by each bogie rotation center (350). By connecting these two bogie rotation centers (350), a 2-axle bogie for various uses can be configured.

[0080] As illustrated in FIG. 9, the two-axle bogie for a freight train has two bogie rotation centers (350) of two single-axle bogies (300) firmly connected to a single two-axle bogie frame (370). A single bogie frame rotation center (380) is installed in the center of this two-axle bogie frame (370) to support the car body of the freight train. The bogie frame rotation center (380) is a device that connects the bogie to the car body of the freight train to transmit the load while allowing the bogie to rotate freely. This two-axle bogie for a freight train is a structure suitable for freight trains that must stably support heavy loads.

[0081] To support railway vehicles that transport heavy loads of 150 tons or more, such as locomotives or freight cars, a bogie with three axles is required. However, since the three wheels of a three-axle bogie are arranged in a straight line, there is a problem where the wheels and rails are damaged due to collisions or friction when passing through curves.

[0082] To solve this, the present invention provides a three-axle bogie with an original structure as illustrated in FIG. 11. This is configured by combining a fixed bogie (520) consisting only of driving wheels (110) without a safety wheel (210) in the center, and two single-axle bogies (300) positioned at the front and rear of the fixed bogie (520), respectively, into a single three-axle bogie frame (510). A bogie frame rotation center (380) is installed in the center of the upper surface of the three-axle bogie frame (510) to support the body of the railway vehicle.

[0083] Specifically, a fixed bogie (520) without a degree of rotational freedom is directly connected to the central lower part of the 3-axle bogie frame (510), and a 1-axle bogie (300) that is free to rotate is connected to the front and rear of it through the bogie rotation center (350).

[0084] When a three-axle bogie is configured in this way, the central fixed bogie (520) does not have safety wheels (210) that support the inner side of the rail (500), and the driving wheels (110) are made of cylindrical wheels. Since these cylindrical wheels are not constrained by the curved rail and move freely horizontally while driving on the upper surface of the rail, a three-axle bogie is configured to smoothly pass through the curved section. Because the three-axle bogie travels safely without derailing from the rail with the safety wheels (210) installed on the front one-axle bogie (300) and the rear one-axle bogie (300), the cylindrical wheels mounted on the central fixed bogie directly connected to the bogie also travel without leaving the rail, thereby configuring a three-axle bogie for a locomotive or freight car required for transporting heavy loads.

[0085] The driving wheel (110) of the fixed bogie (520) of the 3-axle bogie must have a sufficient width, and the width of the wheel is expanded to more than twice the distance between the straight line and the arc formed by the length of the straight bogie and the curved rail at the minimum curve radius in which the railway vehicle travels, thereby solving the friction problem that occurs on the curved section rail of the 3-axle bogie.

[0086] We have summarized the technical content of the specification filed on September 16, 2024, and from here on, we will describe an articulated two-axle bogie, which is an embodiment of the new technology newly added to this specification. The articulated two-axle bogie (Fig. 10) described below is a novel embodiment not included in the basic application filed on September 16, 2024, and is filed based on the date of this international filing. Therefore, this embodiment is not included in the scope of the priority claim and is presented as an additional variation of the present invention. Furthermore, Claim 10 of this specification is a newly added matter and is not included in the basic application; thus, priority does not apply.

[0087] FIG. 10 is a perspective view of an articulated 2-axle bogie for a passenger train constructed using two 1-axle bogies (300) of the present invention. This is a drawing additionally created to explain the new device configuration, and the articulated 2-axle bogie is a structure optimized for passenger trains where high-speed driving stability and passenger convenience are important.

[0088] The articulated two-axle bogie is similar to a cargo bogie in that the two-axle bogie frame (370) is connected to the two one-axle bogies (300) shown in FIG. 8. However, the biggest difference lies in the method of connecting the two-axle bogie frame (370) to the vehicle body. In the articulated two-axle bogie, two-end connecting parts (390) are installed on both sides of the two-axle bogie frame (370) to connect two adjacent vehicle bodies. These two-end connecting parts (390) are devices that connect the two adjacent passenger vehicle bodies to the bogie while providing load transfer and smooth rotation between the vehicle body and the bogie. Thus, the two two-end connecting parts (390) each serve to connect and support the ends of two different adjacent passenger vehicles.

[0089] This articulated two-axle bogie structure reduces the number of bogies required for the entire train, thereby reducing the overall weight and manufacturing costs. In addition, since the vehicles are fixed together, relative movement between the vehicles is minimized, which greatly improves stability during high-speed driving and enables smooth driving when passing through curved sections, thereby enhancing ride comfort. This is a new embodiment in which a two-axle bogie module made from a one-axle bogie (300) of the present invention can be effectively applied to a passenger train system.

[0090] As described above, preferred embodiments of the present invention have been illustrated and described with reference to the drawings; however, the present invention is not limited to the specific embodiments described above. Various modifications are possible by those skilled in the art without departing from the essence of the invention as claimed in the patent claims, and such modifications should not be understood individually from the technical spirit or perspective of the present invention.

[0091] The present invention relates to a railway vehicle with a novel structure that runs on cylindrical wheels and its bogie, which can be actually manufactured and used in the railway transportation industry.

[0092] The 1-axle bogie according to the present invention is a basic module, and by applying it, it is possible to manufacture railway vehicles for various purposes, such as 2-axle bogies for freight trains, articulated 2-axle bogies for passenger trains, and 3-axle bogies for transporting heavy loads like locomotives.

[0093] Therefore, the present invention has industrial applicability as it can be used in the industry producing next-generation railway vehicles and core components that overcome the limitations of existing railway systems by fundamentally eliminating hunting motion and providing a basis for 'active driving'.

Claims

In the case of a railway vehicle running on rails, A pair of driving wheels (110) that support the vertical load of the above railway vehicle and are made of a cylinder with a flat outer surface; and It includes a safety wheel (210) that is provided separately from the driving wheel (110) and contacts the inner surface of the rail to restrict the lateral movement of the driving wheel (110); A railway vehicle running on cylindrical wheels, characterized in that a pair of the above-mentioned driving wheels (110) rotate independently of each other. In paragraph 1, The above driving wheel (110) and the above safety wheel (210) are combined to form a 1-axle bogie (300), A railway vehicle that runs on cylindrical wheels, characterized in that the above-mentioned axle bogie (300) further includes a bogie rotation center (350) that is horizontally rotatably connected to the railway vehicle. In paragraph 2, The above-mentioned 1-axle bogie (300) comprises a wheel set (100) including the driving wheel (110); A wheel trolley (310) connected to support the above wheel set (100); and A railway vehicle running on cylindrical wheels, characterized by including a vertical connecting unit and a suspension unit that allow vertical movement and reduce vibration between the wheel set (100) and the wheel bogie (310). In paragraph 2, The above bogie rotation center (350) has a vertical rotation axis, A railway vehicle that runs on cylindrical wheels, characterized in that a pair of the above-mentioned driving wheels (110) form a common horizontal center axis, and the vertical rotation axis and the horizontal center axis are orthogonal. In paragraph 2, A railway vehicle that runs on cylindrical wheels, characterized by active driving that controls the direction of travel of the 1-axle bogie (300) by controlling the rotational speed of each of the left and right driving wheels (110). In paragraph 1, A railway vehicle running on a cylindrical wheel, characterized in that the safety wheel (210) has a conical outer surface and is positioned so that the outer surface contacts the inner surface of the rail. In paragraph 1, A railway vehicle running on cylindrical wheels, further comprising a wear dispersion device for dispersing wear on the above-mentioned driving wheels (110). In paragraph 2, A railway vehicle that runs on cylindrical wheels, characterized in that two of the above-mentioned single-axle bogies (300) are connected to a two-axle bogie frame (370) to form a two-axle bogie. In paragraph 2, A railway vehicle that runs on cylindrical wheels, characterized in that a fixed bogie without a safety wheel (210) in the center and two 1-axle bogies (300) arranged at the front and rear of the fixed bogie are connected by a 3-axle bogie frame (510) to form a 3-axle bogie. In paragraph 8, The above-mentioned two-axle bogie is, A railway vehicle that runs on cylindrical wheels, characterized by being an articulated two-axle bogie having two end connecting parts (390) connecting two adjacent vehicle bodies on both sides of the above two-axle bogie frame (370).

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