Counter-rotating axial-flow fan

Abstract

A counter-rotating axial-flow fan includes a housing that is constituted from a first divided housing unit and a second divided housing unit. Engaging members and first stopper portions are integrally formed with a first flange portion of the first divided housing unit. The first stopper portions are arranged adjacent to the engaging members. Engaged members and second stopper portions are integrally formed with a second flange portion of the second divided housing unit. The second stopper portions are arranged adjacent to the engaged members. The second stopper portions have leading ends that are abutted onto leading ends of the first stopper portions when the engaging members are completely engaged with the engaged members. Thus, damage of the first and second divided housing units is prevented when the first and second divided housing units are coupled.

1 . A counter-rotating axial-flow fan comprising:
 a housing comprising a housing body including an air channel having a suction opening on one side in an axial line direction and a discharge opening on the other side in the axial line direction, and a motor support frame disposed in a central portion of the air channel;   a first impeller disposed in a first space, which is defined between the motor support frame in the housing and the suction opening, and including a plurality of blades;   a first motor including a first rotary shaft onto which the first impeller is fixed, the first motor rotating the first impeller in a first rotating direction within the first space;   a second impeller disposed in a second space, which is defined between the motor support frame in the housing and the discharge opening, and including a plurality of blades; and   a second motor including a second rotary shaft onto which the second impeller is fixed, the second motor rotating the second impeller in a second rotating direction opposite to the first rotating direction within the second space;   the motor support frame comprising a support frame body disposed in the central portion of the air channel and a plurality of webs disposed between the support frame body and the housing body at predetermined intervals in a circumferential direction of the rotary shafts, the webs connecting the support frame body and the housing body;   the housing being constituted from first and second divided housing units that are coupled through a coupling structure;   the first divided housing unit including a first housing-body half-portion and a first support-frame half-portion, the first housing-body half-portion including a first flange portion having the suction opening at one end thereof and a first cylindrical air-channel half-portion of which one end is integrally formed with the first flange portion, the first cylindrical air-channel half-portion containing therein a major part of the first space, the first support-frame half-portion being obtained by dividing the motor support frame into two along a virtual reference dividing plane extending in a radial direction of the rotary shafts orthogonal to the axial line direction;   the second divided housing unit including a second housing-body half-portion and a second support-frame half-portion, the second housing-body half-portion including a second flange portion having the discharge opening at one end thereof and a second cylindrical air-channel half-portion of which one end is integrally formed with the second flange portion, the second cylindrical air-channel half-portion containing therein a major part of the second space, the second support-frame half-portion being obtained by dividing the motor support frame into the two along the virtual reference dividing plane, wherein   the coupling structure is constituted from:   a fitting portion formed at the other end of the first cylindrical air-channel half-portion,   a fitted portion to be fitted with the fitting portion, formed at the other end of the second cylindrical air-channel half-portion,   a plurality of engaging members integrally formed with the first flange portion, arranged at intervals in the circumferential direction, and extending along the first cylindrical air-channel half-portion, and   a plurality of engaged members to be respectively engaged with the engaging members, integrally formed with the second flange portion, arranged at intervals in the circumferential direction, and extending along the second cylindrical air-channel half-portion;   a plurality of first stopper portions are integrally formed with the first flange portion and arranged adjacent to the engaging members, and extend along the first cylindrical air-channel half-portion;   a plurality of second stopper portions are integrally formed with the second flange portion and arranged adjacent to the engaged members, and extend along the second cylindrical air-channel half-portion; and   leading ends of the first stopper portions are respectively abutted onto leading ends of the second stopper portions when the engaging members are completely engaged with the engaged members.   
     
     
         2 . The counter-rotating axial-flow fan according to  claim 1 , wherein
 the first and second flange portions respectively have a contour shape including four corners, first to fourth corners, arranged in the circumferential direction;   four of the engaging members and four of the first stopper portions are respectively arranged in the vicinity of the four corners of the first flange portion;   four of the engaged members and four of the second stopper portions are respectively arranged in the vicinity of the four corners of the second flange portion;   in the first flange portion, two of the engaging members are arranged in a region defined between the first corner and the second corner, two of the first stopper portions are arranged in a region defined between the second corner and the third corner, two of the engaging members are arranged in a region defined between the third corner and the fourth corner, and two of the first stopper portions are arranged in a region defined between the fourth corner and the first corner; and   in the second flange portion, two of the engaged members are arranged in a region defined between the first corner and the second corner, two of the second stopper portions are arranged in a region defined between the second corner and the third corner, two of the engaged members are arranged in a region defined between the third corner and the fourth corner, and two of the second stopper portions are arranged in a region defined between the fourth corner and the first corner.   
     
     
         3 . The counter-rotating axial-flow fan according to  claim 1 , wherein the engaging members are integrally coupled to the first cylindrical air-channel half-portion, and the engaged members are integrally coupled to the second cylindrical air-channel portion. 
     
     
         4 . The counter-rotating axial-flow fan according to  claim 2 , wherein when a first virtual diagonal line connecting two of the four corners opposed to each other in the radial direction of the rotary shafts and a second virtual diagonal line connecting remaining two of the four corners are assumed in the first flange portion, the engaging member and the first stopper portion corresponding to the engaging member are disposed so as to interpose the first or second virtual diagonal line therebetween;
 none of the engaging members and none of the first stopper portions are disposed at the four corners through which the first or second virtual diagonal line passes;   when a third virtual diagonal line connecting two of the four corners opposed to each other in the radial direction of the rotary shafts and a fourth virtual diagonal line connecting remaining two of the four corners are assumed in the second flange portion, the engaged member and the second stopper portion corresponding to the engaged member are disposed so as to interpose the third or fourth virtual diagonal line therebetween; and   none of the engaged members and none of the second stopper portions are disposed at the four corners through which the third or fourth virtual diagonal line passes.   
     
     
         5 . The counter-rotating axial-flow fan according to  claim 1 , wherein
 one of the engaging member and the engaged member includes a claw portion;   the other of the engaging member and the engaged member includes a hole portion to be engaged with the claw portion;   at least one of the engaging member and the engaged member ( 41 A- 41 D) is bent when engaging the engaging member with the engaged member, and the claw portion and the hole portion get into engagement with each other once the engaging member is completely engaged with the engaged member; and   the hole portion is formed so as to allow for visual confirmation of the engagement of the claw portion engaged therewith.   
     
     
         6 . The counter-rotating axial-flow fan according to  claim 1 , wherein
 the engaging members and the first stopper portions are respectively shaped not to protrude outside the first flange portion as the first flange portion is seen from the first cylindrical air-channel half-portion; and   the engaged members and the second stopper portions are respectively shaped not to protrude outside the second flange portion as the second flange portion is seen from the second cylindrical air-channel half-portion.   
     
     
         7 . The counter-rotating axial-flow fan according to  claim 2 , wherein the engaging members are integrally coupled to the first cylindrical air-channel half-portion, and the engaged members are integrally coupled to the second cylindrical air-channel portion.