FORCED DRAFT COOLING SYSTEM FOR DIESEL-ELECTRIC LOCOMOTIVE

Abstract: A cooling system wherein a radiator (6) is mounted on a side surface of the locomotive body (1) and a dynamic brake resistor (7) is disposed at the inner side of the radiator (6). A radiator fan (4) provided in the intermediate part of the body (1) is driven for taking in air from the outside through the radiator (6) thereby to cool both the radiator (6) and the dynamic brake resistor (7). The system is characterized in that the dynamic brake resistor (7) is disposed at the inner side of the radiator (6), close and in parallel thereto, and is divided into a plurality of units (7a), which are arranged so as to be distributed within the draft area of the radiator (6).

Description: FORCED DRAFT COOLING SYSTEM FOR DIESEL-ELECTRIC LOCOMOTIVE BACKGROUND OF THE INVENTION FIELD OF THE INVENTION The present invention relates to a forced draft cooling system for a diesel-electric locomotive and more particularly to a cooling system for a dynamic brake resistor of a diesel-electric locomotive. DESCRIPTION OF THE PRIOR ART In a typical conventional diesel-electric locomotive, a radiator apparatus for the cooling water for a diesel engine which comprises a radiator core, radiator fan and so forth and a dynamic brake apparatus having a resistor are generally disposed at different positions spaced in the longitudinal direction of the locomotive body. Therefore1 the body length must be unfavorably long. As a means for overcoming the above disadvantage, such an arrangement has been proposed in which the radiator core is disposed on a side surface of the body, while the radiator fan is disposed in the center thereof, and the dynamic brake resistor is disposed above the radiator fan. The above arrangement permits both the radiator core and the resistor to be cooled by a single radiator fan as well as eliminates the need for enlarging the body length. However, since the resistor is exposedly disposed on the upper surface of the body, elements of the resistor which become high in temperature and supporting insulators thereof are undesirably exposed to rainwater to shorten the life thereof. In order to overcome these disadvantages, another arrangement has been proposed by the same applicant as above in which the radiator is disposed on a side surface of the body, while the dynamic brake resistor is disposed at the inner side of the radiator with a proper distance provided therebetween, and both are forcedly cooled by air moved by a mutual fan. This arrangement, however, still has the following problems. Namely, since the radiator and the dynamic brake resistor are simultaneously cooled by forced draft, there is, as a matter of course, a need for an air flow lager than that for cooing only the radiator or the resistor. Consequently, the cooling air passing through the radiator becomes high in wind velocity, and since the draft area of the resistor is smaller than that of the radiator, the existence of the resistor causes the wind velocity distribution within the draft area of the radiator to be ununiform. For above and other reasons, radiator core fins vibrate in portions of the radiator where the wind velocities are particularly high, unfavorably producing vibration noises. In addition, since the resistor is installed within a limited space at the inner side of the radiator, it is extremely difficult to demount and remount the resistor in maintenance and inspection. SUMMARY OF THE INVENTION It is, therefore,- a primary object of the invention to provide a forced draft cooling system for a diesel-electric locomotive in which a dynamic brake resistor is disposed at the inner side of a radiator, capable of preventing the production of vibration noises of radiator core fins as well as easily performing the maintenance and inspection of the dynamic brake resistor, thereby overcoming the above-mentioned disadvantages of the prior art. To this end, according to the invention, there is provided a forced draft cooling system for a dieselelectric locomotive having a radiator for a diesel engine disposed on a side surface of the locomotive body, a dynamic brake resistor disposed at the inner side of the radiator, and a fan for sucking in a cooling air through the radiator and the resistor, characterized in that the resistor is divided into a plurality of units, which are arranged so as to be distributed within the draft area of the radiator. The above and other objects, features and advantages of the invention will become clear from the following description of the preferred embodiment taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a plan view of the whole of a dieselelectric locomotive employing a cooling system for a dynamic brake resistor thereof in accordance with a preferred embodiment of the invention; Fig. 2 is a side elevational view of the diesel-electric locomotive shown in Fig. 1; Fig. 3 is a plan view of a radiator part of the diesel-electric locomotive shown in Fig. l; Fig. 4 is a sectional view taken along a line IV-IV of Fig. 3; Fig. 5 is a sectional view taken along a line V-V of Fig. 3; and Fig. 6 is an enlarged view of a part F of Fig. 5. DESCRIPTION OF THE PREFERRED EMBODIMENT On a locomotive body 1, a main generator 2, a diesel engine 3, and a radiator fan 4 driven through a radiator fan driving device 5 are disposed successively in the longitudinal direction of the body 1. A dynamic brake resistor 7 (see Fig. 3) is disposed at the inner side of the corresponding one of radiators 6 disposed on both side surfaces of the locomotive body 1, respectively. The resistor 7 is divided into a plurality of resistor units 7a, which are arranged so as to be distributed within the draft area of the corresponding radiator 6. As will be apparent from Fig. 3, each radiator 6 is const tuted by three radiator units 6a, which are divided in the widthwise direction and arranged with a gap b (generally from 1.0 to 20 mm) for draft provided between the adjacent ones. Moreover, a gap c (generally from 50 to 70 mm) for draft is provided also between the radiator units 6a and a mounting frame 8 secured to the body I. Each radiator 6 and the corresponding dynamic brake resistor 7 are disposed in parallel with each other with.a gap H of from 50 to 300 mm provided therebetween. The resistor units 7a constituting the dynamic brake resistor 7 are arranged with a gap a for draft provided therebetween, and are fixed to a lower resistor support 9a and an upper resistor support 9b, which are fixed to the body 1, through resistor supporting insulators 10 arranged such that the longitudinal axes of the insulators disposed in the upper part of the body 1 are perpendicular to the plane of the resistor 7, while the insulators disposed in the lower part of the body 1 are vertical so as to receive the load of the resistor-7. This mounting structure facilitates the mounting operation inside the body 1. Insulator covers 11 are provided above the supporting .insulators 10, respectively, for protection of the latter in case rain or the like enters from the upper part of the body 1. Partition walls 12 for allowing the radiator room to be an independent room are disposed at the frontward and rearward portions of the body 1, respectively, and are inclined so as to taper toward the center of the radiator room in order to allow air to circulate excellently. A reference numeral 14 denotes each of baffle plates for guiding the air passing through the radiator toward the resistor units 7a, while a numeral 15 designates each of holes formed in each baffle plate 15 in order to regulate air flow. A fan 4 for draft is disposed in the central upper part of the body 1 and adapted to suck in a cooling air through the radiators 6 mounted on the body side surfaces and the dynamic brake resistors 7 and discharge the cooling air heated there from the body upper surface. The fan 4 is driven by the diesel engine 2 through a propeller shaft 20, a gear box 21 and a vertical shaft 22. The fan 4 may, as a matter of course, be driven by means of an independent drive motor. Vent holes 13 for taking in a cooling air for lowering the temperature of the gear box 21 are formed in the partition wall 12 remoter from the diesel engine 3. According to the above arrangement, since the units 7a constituting the dynamic brake resistor 7 are arranged so as to be distributed within the draft area of the radiator 6, the wind velocities within the draft area of the radiator 6 become relatively uniform, so that there will be no portion having a locally high wind velocity. Accordingly, it is possible to prevent production of vibration noises of the radiator core fins. Moreover, in the above embodiment, the gap b is provided between the adjacent radiator units 6a, and each resistor unit 7a is disposed so as to correspond to the gap b. Therefore, the cooling air passing through the gap b, i.e., the cooling air not heated by the radiator units 6a, is made to directly blow against the corresponding resistor unit 7a, thereby allowing the resistor units 7a to be improved in cooling efficiency. Furthermore, since the dynamic brake resistor 7 is divided into a plurality of units, each resistor unit 7a is compact and lightweight, so that. it becomes extremely easy to demount and remount the resistor units 7a in a narrow space in maintenance and inspection. In addition, since elements 19 shown in Fig. 6 become short in span, the sag of the elements 19 due to thermal expansion becomes small, so that there will be no short-circuit accident of the elements 19 due to sagging. It is to be noted that although the dynamic brake resistor on each side is divided into two in the above-described embodiment, it is possible to divide the resistor into three or more. Moreover, if the gap c is provided also between each radiator 6 and the corresponding mounting frame 8, a cooling air easily flows in also through the gap c, .thereby allowing a more appropriate air flow to be obtained. Furthermore, the air flowing in through the radiators 6 and the resistors 7 has a high temperature, since it is heated by both of them. Therefore, there is a possibility that the heated air may have adverse effects on such peripheral devices as the radiator fan driving device 5, the radiator fan 4 and so forth. Provided in order to eliminate such a possibility are the vent holes 13 formed in the partition wall 13 remoter from the diesel engine 3. The vent holes 13 are adapted to allow the cooling air for cooling a compressor in a compressor room (not shown) to flow in therethrough. Thereby, the radiator room is cooled, and the above-mentioned problem can be solved. As has been described, according to the invention, since the dynamic brake resistor is divided into a plurality of units and arranged so as to be distributed within the draft area of.the radiator, the wind velocities of the cooling air passing through the radiator are uniformed, so that there will be no portion having an extremely high wind velocity. Accordingly, it is possible to prevent production of vibration noises of the radiator core fins. In addition, since the dynamic brake resistor is divided into a plurality of units, each unit is compact and lightweight. Therefore, it becomes easy to demount and remount the resistor units in maintenance and inspection and moreover, it is possible to prevent a short-circuit accident of the elements due to the sagging thereof. Although the invention has been described through specific terms, it is to be noted here that the described embodiment is only illustrative and not exclusive, and the invention covers all possible changes and modifications imparted to the described embodiment within the scope of spirit of the invention which is limited solely by the appended claims.

Claims: WHAT IS CLAIMED IS: 1. A forced draft cooling system for a diesel-electric locomotive wherein a radiator (6) is mounted on a side surface on the body (1) of said diesel-electric locomotive and a dynamic brake resistor (7) is disposed at the inner side of said radiator (6), and a radiator fan (4) provided in the intermediate part of said body (1) is driven for taking in air from the outside of said body (1) through said radiator (6) thereby to cool both said radiator (6) and said dynamic brake resistor (7), characterized in that said dynamic brake resistor (7) is disposed at the inner side of said radiator (6), close and in parallel thereto, and is divided into a plurality of units (7a), which are arranged so as to be distributed within the draft area of said radiator (6). 2. The system of claim 1, wherein said radiator (6) is divided into a plurality of units (6a), and a gap (b) for passing the outside air is provided between each adjacent ones of said plurality of units (6a). 3. The system of claim 1 or 2, wherein a gap (c) for passing the outside air is provided between said radiator (6) and a mounting frame (8) for mounting said radiator (6). 4. The system of any of claims 1 to 3, wherein the gap (H) between said radiator (6) and said dynamic brake resistor (7) is from 50 to 300 mm. 5. 'The system of any of claims 2 to 4, wherein each of said plurality of units (7a) constituting said dynamic brake resistor (7) is disposed so as to correspond to a gap (bY provided between each adjacent ones of a plurality of radiator units (6a) constituting said radiator (6). 6. The system of any of claims 1 to 5, wherein a baffle plate (14) for guiding the air passing through said radiator (6) toward said dynamic brake resistor (7) is provided on a side of said radiator (6). 7. The system of any of claims 1 to 6, wherein said dynamic brake resistor (7) is fixed to resistor supports -(9a, 9b) disposed in the upper and lower parts of said body (1) through resistor supporting insulators (10). 8. The system of claim 7, wherein said resistor supports (9a, 9b) are provided with rain covers t11) covering said resistor supporting insulators (10), respectively. 9. The system of claim 7 or 8, wherein said resistor supporting insulators (10) are arranged such that the longitudinal axes of the resistor supporting insultors (10) disposed in the upper part of said body 41) are perpendicular to the plane of said dynamic brake resistor (7) and the resistor supporting insulators (10) disposed in the lower part of said body (1) are vertical so as to receive the load of said dynamic brake resistors (7). 10. The system of any.of claims 1 to 10, wherein a vent hole (13) is formed in one of partition walls (12) separating said radiator fan (4) and the like disposed more remote from a diesel engine (3).

Inventors: ICHIGE, TUTOMU, KIKUCHI, ICHIRO, SATO, MASATOSHI
Applicants: HITACHI, LTD.
Application year: 1983
Main classification: B61C5
IPC codes: B61C5, F02B3