Patent Description:
In general, railroad cars are one of the important means of transportation constituting passenger trains, freight trains, and electric trains running on railroad tracks. A number of railroad cars connected in series can carry hundreds or thousands of passengers while driving safely, as well as simultaneously transport a large amount of cargo.

The railroad cars travel as a train with a plurality of connected railroad cars, and a coupler is used to connect a railroad car to another railroad car.

The coupler prevents accidents caused by contact between a leading car and a rear car by always maintaining a predetermined distance therebetween. The coupler serves as a medium to transmit power from an engine room to each car, and a knuckle type automatic coupler or a lock type close coupler is mainly used as the coupler.

Transcontinental railroads refer to a railroad route that is being promoted with a goal of connecting Korea to China, Central Asia, Russia, and Europe.

In a case of freight cars among transcontinental railroads cars passing through various countries, it may be necessary to connect an additional car to the transcontinental railroads cars in order to add freight to be transported from a specific country to another country.

However, there is no a worldwide standardized railroad car coupler, and each country has different coupler standards. Therefore, when a railroad car moving from one country to another is connected to the railroad cars, a coupler must be replaced, and it takes a lot of time and money to replace the coupler.

As a related art to solve the above problem, <CIT> proposed a rotatable twin headed coupler for railroad cars. As shown in <FIG>, the coupler includes: a knuckle member <NUM> formed at one portion of the coupler; a contact plate <NUM> provided at a lower portion of the knuckle member <NUM> and on which a protrusion <NUM>' is formed, wherein the knuckle member <NUM> and the protrusion <NUM>' are disposed to be perpendicular to each other on a shaft hole <NUM>; a coupler body <NUM> having a stopper <NUM>, <NUM>' and securing pin holes <NUM> that are formed around the shaft hole <NUM> by a mutually appropriate interval; and a shank <NUM> having a fitted part <NUM>' in which a shaft hole <NUM>' and a securing hole <NUM> are formed. A connecting shaft <NUM> is inserted through the coupler body <NUM> and the shaft hole <NUM>, <NUM>' of the shank <NUM>, and one of the securing pin holes <NUM> and the securing hole <NUM> of the shank <NUM> match with each other while being adjusted by the stopper <NUM>, <NUM>', the holes being formed around the shaft hole <NUM> of a coupler body <NUM>. A securing pin <NUM> is inserted into the securing pin hole and the securing hole <NUM> to selectively use a coupler matching with a coupler provided in a car to be connected.

In the related art, the coupler body <NUM> has two different head forms integrated into a single body so that it is possible to connect car frames having different type couplers to each other without replacement of a coupler. However, the coupler body <NUM> having the two different head forms is supported to the shank <NUM> only by a hinge coupling part, so support strength of the coupler may be week.

In the related art, among the two different head forms, a head not in use, i.e. a head not coupled to the car body, is projected in one direction so that the center of gravity of the coupler body <NUM> is biased to in the one direction. Then, when the railroad cars travel, the load on the coupler body <NUM> during traveling is eccentrically operated. Therefore, the traveling stability of the railroad car is degraded, and the load on a coupling portion between the shank <NUM> and the coupler body <NUM> causes deformation or breakage of the coupler.

Accordingly, the present disclosure has been made keeping in mind the above problems occurring in the prior art, and an objective of the present disclosure is to provide a coupler structure for transcontinental railroad cars, the coupling structure being configured to increase the support strength with respect to the load on a head unit having two different coupler forms integrated into a single body, during traveling of a transcontinental railroad car, to improve the durability of the head unit.

Another objective of the present disclosure is intended to provide a coupler structure for transcontinental railroad cars, the coupler structure being configured to distribute the load on the coupler during traveling of a transcontinental railroad car to prevent the traveling stability of the transcontinental railroad car from being degraded due to the eccentric load.

In order to achieve the above objectives, according to one aspect of the present disclosure, a coupler structure for transcontinental railroad cars is configured as follows.

The coupler structure for transcontinental railroad cars includes a head unit having two different coupler forms integrated into a single body; and a shank unit connected to a railroad car body while being coupled to the head unit, wherein the shank unit may include a U-shaped head connector part and a securing part, the head unit being inserted into and hinged to the U-shaped head connector part, and the securing part extending from a rear end of the head connector part and fixedly mounted on the car body, supporting parts may be projected from upper and lower surfaces of a rear end of the head unit, and supporting grooves into which the supporting parts may be inserted may be formed on an inner surface of the head connector part.

The supporting parts and the supporting grooves may be formed in arc forms.

First and second hinge holes, into which a hinge pin may be inserted and coupled, may be respectively formed in a location of the head unit and a location of the head connector part that correspond to each other, and an insertion hole and a coupling hole, into which a securing pin for securing the head unit to the head connector part may be inserted and coupled, may be respectively formed on rear portions of the first and second hinge holes.

The insertion hole may include first to third insertion holes that may be spaced apart from each other at predetermined intervals, and the coupling hole may include first and second coupling holes that may be spaced apart from each other at a predetermined interval, and the securing pin may include first and second securing pins that may be respectively coupled to the first and second coupling holes and the first and second insertion holes or to the first and second coupling holes and the second and third insertion holes.

A supporting frame may be coupled to a location outside the head connector part, the supporting frame having an accommodating space for accommodating the head unit therein.

First and second connector parts may be respectively projected on opposite portions of the head unit, the first and second connector parts being configured to be fastened and secured to the head connector part by a fastening means while being accommodated in the accommodating space of the supporting frame.

A heating wire may be inserted and provided in the supporting frame.

According to the present disclosure, during traveling of a transcontinental railroad car, the coupling structure can support the head unit having the two different coupler forms integrated into a single body more stably, distribute eccentric load, bending load, torsional load, etc. on the coupler, and improve the load support strength of the coupler. Therefore, the traveling stability of a transcontinental railroad car can be improved and the durability of the coupler can be dramatically improved.

Hereinbelow, a coupler structure for transcontinental railroad cars according to preferred embodiments of the present disclosure will be described in detail with reference to accompanying drawings.

<FIG> is a perspective view showing a coupler structure for transcontinental railroad cars according to a first embodiment of the present disclosure. <FIG> is an exploded-perspective view showing the coupler structure for transcontinental railroad cars shown in <FIG>. <FIG> is an axial-sectional view showing the coupler structure for transcontinental railroad cars shown in <FIG>. <FIG> is an exploded-perspective view showing a coupler structure for transcontinental railroad cars according to a second embodiment of the present disclosure. <FIG> are views showing the coupler structure of the present disclosure shown in <FIG> to which another coupler having a different shape is coupled. <FIG> is a view showing results of structural analysis of the coupler structure of the present disclosure shown in <FIG>. <FIG> is a perspective view showing a coupler structure for transcontinental railroad cars according to a third embodiment of the present disclosure. <FIG> is a plan view showing the coupler structure of the present disclosure shown in <FIG>.

The present disclosure relates to a coupler structure for transcontinental railroad cars, the coupled structure increasing support strength of a duplex coupler provided in transcontinental railroad cars and improving durability by distributing the load on the coupler. The coupler structure includes a head unit <NUM> and a shank unit <NUM>, as shown in <FIG> and <FIG>.

Specifically, the head unit <NUM> serves to connect a car body to another car body, the car bodies being adjacent to each other. The head unit <NUM> has a structure in which two different coupler forms are integrated into a single body.

The coupler forms included in the head unit <NUM> may include two forms among widely used various coupler forms. The coupler structure of the present disclosure is used for transcontinental railroad cars, so the form of the head unit <NUM> may be the structure consisting of an AAR (Association of American Railroads) type coupler (a first coupler 100a) used in most countries including Korea and a CA-<NUM> type coupler (a second coupler 100b) mainly used in Russia and China are integrated into a single body, as shown in <FIG>. The present disclosure will be described with reference to the above structure.

The shank unit <NUM> is connected to a rear portion of the head unit <NUM> and serves to allow the coupler <NUM> to be fixedly mounted to the car body of a transcontinental railroad car. The shank unit <NUM> includes a head connector part <NUM> and a securing part <NUM>. The head unit <NUM> is hinged to the head connector part <NUM>, and the securing part <NUM> is fixedly mounted to the car body.

More specifically, the head connector part <NUM> is formed in a 'U'-shape having an open front portion so that the head unit <NUM> may be inserted into and coupled to the inside of the head connector part <NUM> through the open portion. The securing part <NUM> is formed in a shank shape that extends rearward of the head connector part <NUM>. A rear end of the securing part <NUM> is coupled to the car body, whereby the coupler <NUM> may be fixedly mounted to the car body.

A first hinge hole <NUM> is vertically formed in a center portion of the head unit <NUM>, and a second hinge hole <NUM> is formed in a portion of the head connector part <NUM> that corresponds to the location of the first hinge hole <NUM>. The above-described structure may be configured such that, the head unit <NUM> may be hinged to the inside of the head connector part <NUM> by a hinge pin <NUM>.

The head unit <NUM> is hinged to the inside of the head connector part <NUM> by the hinge pin <NUM> that is inserted into and coupled to the second hinge hole <NUM> formed in the head connector part <NUM> and the first hinge hole <NUM> formed in the head unit <NUM>. Therefore, even when the coupler <NUM> needs to be replaced, the hinge pin <NUM> serves as a shaft, without separating the head unit <NUM> from the head connector part <NUM>, the first coupler 100a and the second coupler 100b may be replaced by rotation on the hinge pin <NUM>.

Meanwhile, an insertion hole <NUM> is formed at rear of the first hinge hole <NUM> formed in the head unit <NUM>, and a coupling hole <NUM> is formed on a location, which corresponds to the location of the insertion hole <NUM>, in rear of the second hinge hole <NUM> formed in the head connector part <NUM>. The insertion hole <NUM> and the coupling hole <NUM> serve to receive and to be coupled to a securing pin <NUM> provided for fixing the head unit <NUM>.

The securing pin <NUM> serves to solidly fix the head unit <NUM> to the head connector part <NUM> of the shank unit <NUM> and to support the load applied to the coupler <NUM> during traveling of a transcontinental railroad car. While the head unit <NUM> is coupled to the head connector part <NUM> by the hinge pin <NUM>, the securing pin <NUM> is inserted into and coupled to the head unit <NUM> and the head connector part <NUM> through the insertion hole <NUM> and the coupling hole <NUM> respectively formed in the head unit <NUM> and the head connector part <NUM>. Accordingly, the head unit <NUM> may be solidly fixed to the head connector part <NUM>.

As shown in <FIG>, supporting parts <NUM> are respectively formed while being projected on upper and lower surfaces of a rear end of the head unit <NUM>, and supporting grooves <NUM> into which the supporting parts <NUM> are inserted are formed on an inner surface of the head connector part <NUM>. The supporting parts <NUM> and the supporting grooves <NUM> serve to improve support strength of the head unit <NUM> coupled to the head connector part <NUM>.

Conventionally, during traveling of a transcontinental railroad car, the load on the coupler <NUM> is supported only by the hinge pin <NUM> and the securing pin <NUM>, so that load support strength is reduced with respect to the load transmitted from various directions, such as eccentric load, bending load, torsional load, etc. On the other hand, according to the present disclosure, the supporting parts <NUM> that are respectively projected on upper and lower portions of the head unit <NUM> are inserted into and coupled to the supporting grooves <NUM> formed on the head connector part <NUM>. Therefore, a supporting area with respect to the head unit <NUM> increases so as to dramatically improve the support strength with respect to the lead on the head unit <NUM>.

As shown in <FIG>, the supporting parts <NUM> and the supporting grooves <NUM> are formed in arc shapes. Therefore, even when the first coupler 100a and the second coupler 100b need to be replaced, that is, even when the head unit <NUM> is rotated on the hinge pin <NUM>, the supporting parts <NUM> may be supported without being separated from the supporting grooves <NUM>.

According to a second embodiment of the present disclosure, the coupler structure for transcontinental railroad cars is configured as follows. The insertion hole <NUM> formed in the head unit <NUM> includes first to third insertion holes 120a, 120b, and 120c that are disposed to be spaced apart from each other at predetermined intervals. The coupling hole <NUM> formed in the head connector part <NUM> also includes first to second coupling holes 214a and 214b that are disposed to be spaced apart from each other at a predetermined interval. The first to third insertion holes and the first and second coupling holes serve to allow the securing pin <NUM>, which is located in rear of the hinge pin <NUM> and fix the head unit <NUM> to the head connector part <NUM>, to be inserted into and coupled to two locations.

As described above, the head unit <NUM> has the first coupler 100a and the second coupler 100b integrated into a single body. When one of the two couplers is used, another coupler not in use, i.e. another coupler that is not coupled to another car body is projected in one side so that the center of gravity of the head unit <NUM> is biased in the one side. When a transcontinental railroad car travels while only the hinge pin <NUM> and the single securing pin <NUM> support the load on the head unit <NUM> of the coupler, the lead on the head unit <NUM> during traveling eccentrically acts. In this case, the traveling stability of the transcontinental railroad car is degraded and the load support strength with respect to the head unit <NUM> is not enough, so that the coupler <NUM> may be deformed or damaged. Therefore, according to the present disclosure, the head unit <NUM> is fixed by first and second securing pins 170a and 170b that is inserted to be spaced apart from each other at rear of a hinge coupling portion between the head unit <NUM> and the head connector part <NUM>, whereby the head unit <NUM> may be solidly fixed to the head connector part <NUM> and the load support strength of the coupler may be improved.

Specifically, the first to third insertion holes 120a, 120b, and 120c formed in the head unit <NUM> are formed in a vertical direction to be spaced apart from each other at predetermined intervals. As shown in <FIG>, the second insertion hole 120b is formed in rear of the first hinge hole <NUM>, and the first and third insertion holes 120a and 120c are formed in left and right of the first hinge hole <NUM> at the same predetermined intervals with the second insertion hole 120b as the center between the first and third insertion holes 120a and 120c. Therefore, the first to third insertion holes 120a, 120b, and 120c are formed in a '¬' shape.

The first and second coupling holes 214a and 214b formed in the head connector part <NUM> are spaced apart from each other at the interval same as an interval between the first and second insertion holes 120a and 120b and an interval between the second and third insertion holes 120b and 120c. The first and second coupling holes 214a and 214b are disposed symmetrically to each other at rear of the second hinge hole <NUM>.

As shown in <FIG>, when the first coupler 100a of the head unit <NUM>, the first securing pin 170a is fixed by being fastened via the first insertion hole 120a and the first coupling hole 214a. The second securing pin 170b is fixed by being fastened via the second insertion hole 120b and the second coupling hole 214b.

Furthermore, as shown in <FIG>, when the second coupler 100b of the head unit <NUM> is used, the first securing pin 170a is fixedly fastened via the second insertion hole 120b and the first coupling hole <NUM>. The securing pin 170b is fixedly fastened via the third insertion hole 120c and the second coupling hole 214b.

As the above structure, the head unit <NUM> may be fixed to the head connector part <NUM> by the first and second securing pins 170a and 170b at the two locations that are spaced from a longitudinal central shaft of the coupler <NUM> at the predetermined interval and are disposed symmetrically to each other. Therefore, it is possible to further support a rear portion of the first or second coupler 100a or 100b not in use of the head unit <NUM>. Furthermore, support strength may increases with respect to the load transmitted from various directions, such as eccentric load, bending load, torsional load on the head unit <NUM>. Therefore, traveling stability of a transcontinental railroad car may be improved.

In addition, when the coupler <NUM> needs to be replaced, such as when a new freight car is added in the transcontinental railroad car at a station, coupling of the head unit <NUM> by the first and second securing pins 170a and 170b is released and the head unit <NUM> is rotated on the hinge pin <NUM>. Then, only an accident the first and second securing pins 170a and 170b are fixedly fastened, and the coupler <NUM> may be replaced.

<FIG> shows results of structural analysis using a finite element analysis program (ANSYS) while applying a tension load condition to an E-type freight car coupler knuckle of the domestic railway vehicle technical standards. When the head unit <NUM> is fixed by using two securing pins, i.e. the first and second securing pins 170a and 170b, as in the present disclosure, the maximum stress was about 608Mpa. In the above result, it was confirmed that the support strength was improved by more than <NUM>% compared to the support strength of the conventional coupler structure that fixes the head unit <NUM> by using a single securing pin <NUM>.

According to a third embodiment of the present disclosure, the coupler structure for transcontinental railroad cars includes a supporting frame <NUM> fixedly mounted to a location outside the head connector part <NUM> of the shank unit <NUM>. The supporting frame has an accommodating space 300a for the head unit <NUM> to be accommodated therein, as shown in <FIG>. First and second fastening holes <NUM> and <NUM>, to which a fastening means <NUM>, such as a bolt, pin, etc. is inserted into and coupled, are formed in portions on upper and lower surfaces of the supporting frame <NUM>.

First and second connector parts <NUM> and <NUM> are respectively projected on opposite portions of the head unit <NUM>. The first and second connector parts <NUM> and <NUM> respectively have first and second fastening holes <NUM> and <NUM> into which the fastening means <NUM> such as a bolt, pin, etc. may be inserted.

The first and second fastening holes <NUM>, <NUM>, <NUM>, and <NUM>, which are respectively formed in the supporting frame <NUM>, the first and second connector parts <NUM>, and <NUM>, are formed on locations corresponding to each other, and thus fixedly mount the head unit <NUM> accommodated in the supporting frame <NUM> by the fastening means <NUM>, that is, mount the first or second coupling 100a or 100b not in use of the head unit <NUM>. The above structure is configured to further support the load on the head unit <NUM> during traveling of a transcontinental railroad car.

More specifically, the first or second coupler 100a or 100b not in use in the head unit <NUM> is partially accommodated inside the supporting frame <NUM>. The portion of the first or second coupler accommodated in the supporting frame <NUM> is fastened and secured to the head connector part by the fastening means <NUM>, which is coupled to the head unit by passing through the first or second fastening holes (<NUM> or <NUM> and <NUM> or <NUM>) of the first and second connector parts <NUM> and <NUM> of the head unit <NUM> and of the supporting frame <NUM>, the first and second fastening holes being formed at locations corresponding to each other. The above-described structure may fix the head unit <NUM> together with the securing pin <NUM> and support the load during traveling of a transcontinental railroad car.

In addition, the first and second connector parts <NUM> and <NUM> projected on the opposite portions of the head unit <NUM> are formed on locations that does not interfere the first or second coupler 100a or 100b to be coupled to a coupler of another car body. The supporting frame <NUM> is able to be fixedly mounted to an under frame (not shown) of the car body, not the head connector part <NUM>.

Meanwhile, the supporting frame <NUM> serves to protect the head unit <NUM> from an external impact, i.e. an impact due to a collision between the car body and an external object, during traveling of a transcontinental railroad car. In this the supporting frame <NUM>, a heating wire (not shown) may be provided while being inserted.

A transcontinental railroad car to which the present disclosure is applied travels in a microthermal climate or polar climate area, so the coupler <NUM> is often frozen by snow or ice. In this case, it may be difficult to perform rotation of the head unit <NUM> and replacement of the first or second coupler 100a or 100b. Therefore, the heating wire is provided inside the supporting frame <NUM> to use heat transmitted from the supporting frame <NUM> to prevent the shank unit <NUM> and the head unit <NUM> from freezing.

Not shown in the drawings, a temperature sensor is provided inside the supporting frame <NUM>, a cockpit of a transcontinental railroad car has a control unit that heats the heating wire in response to the temperature measured by the temperature sensor. Therefore, the present disclosure may be configured such that, a driver can selectively control heating of the heating wire in response to the temperature in the coupler.

According to the present disclosure as described above, the coupler structure for transcontinental railroad cars may stably support the head unit <NUM>, in which the two differentially shaped couplers 100a and 100b are integrated into a single body during traveling of a transcontinental railroad car, distribute eccentric load, bending load, torsional load, etc. on the coupler, and improve the load support strength. Accordingly, the coupler structure of the present disclosure has various advantages such as improvement in the traveling stability of a transcontinental railroad car and drastic improvement in the durability of the coupler <NUM>.

Although the preferred embodiments of the present disclosure have been described for illustrative purposes, the present disclosure is not limited to the embodiments, and those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the present disclosure as disclosed in the accompanying claims.

Claim 1:
A coupler structure (<NUM>) for transcontinental railroad cars, the coupler structure comprising:
a head unit (<NUM>) having two different coupler forms integrated into a single body; and
a shank unit (<NUM>) connectable to a railroad car body while being coupled to the head unit,
wherein the shank unit (<NUM>) comprises a U-shaped head connector part (<NUM>) and a securing part (<NUM>), the head unit (<NUM>) being inserted into and hinged to the U-shaped head connector part (<NUM>), and the securing part (<NUM>) extending from a rear end of the head connector part (<NUM>) and fixedly mountable on the car body,
characterized in that supporting parts (<NUM>) are projected from upper and lower surfaces of a rear end of the head unit (<NUM>), and
supporting grooves (<NUM>), into which the supporting parts (<NUM>) are inserted, are formed on an inner surface of the head connector part (<NUM>).