Cross flow fan structure

A cross flow fan structure comprising: a) a housing integrally formed by plastic material in an injection molding process; b) a cross flow fan integrally formed by plastic material in an injection molding process, the right side of the cross flow fan having a mounting hole in axial direction and a damping/positioning body; c) a motor with an end portion attached to a mounting base whereupon the motor is attached to the housing by use of the mounting base in such a way that the driving shaft of the motor is extended into the mounting hole of the damping/positioning body in a tightly clamping state for driving the cross flow fan in rotational operation. In this way, a cross flow fan module made by material is created. Moreover, a convenient assemble and a vibration resisting effect are achieved for a smooth operation with low noise by use of a skillful combination of the material and by a special structure.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a cross flow fan, and more particularly to a cross flow fan applicable but not limited to a panel meter of a fitness equipment, and the cross flow fan and its housing are made of a plastic material.

2. Description of the Related Art

As exercisers often sweat a lot when working on fitness equipments, it is delightful to have steady cool air blowing directly at the exercisers while they are doing exercises. Referring toFIG. 1for a conventional treadmill machine M, the treadmill machine M includes an axial flow fan installed separately on both sides of a panel meter, and the airflow direction of this type of fan is parallel to the axle. In other words, air is flowing upward instead of blowing directly at an exerciser on the treadmill machine, and such arrangement obviously requires improvements.

Referring toFIGS. 2 and 3for schematic views of a conventional cross flow fan assembly, the assembly comprises a housing11, a motor12and a cross flow fan13. The inventor of the present invention attempts to install a conventional cross flow fan10in a panel meter of a treadmill machine to replace the traditional axial flow fan F, but the following drawbacks are still found in its testing procedure:

1. The housing11and the cross flow fan13of the structure of a conventional cross flow fan10are made of metal plates, and the housing11is manufactured by stamping, riveting and coupling at least four metal plates. With the weight limitation, the metal plates cannot be too thick, and thus the structural strength of the assembled housing11is poor.

2. More importantly, the cross flow fan13is made by riveting and coupling metal plates and metal pillars. As shown inFIGS. 2 and 2A, over ten metal vanes131are embedded into the metal panels132,133having grooves disposed on left and right sides, and then the middle of the left metal panel132is riveted with a bushing133connected to an axle121of the motor12, and the middle of the right metal panel134is riveted with a center shaft135. After a center shaft135is sheathed into a sleeve14, the center shaft135is installed to the housing11by an axial positioning base15. However, most of these cross flow fans10are made of metals, and most of the connections are achieved by stamping, riveting and welding, and thus the manufacture is more complicated, and the required streamline design cannot be achieved easily. If the cross flow fan13is driven by the motor12to rotate transversally in the x-x direction as shown inFIG. 3, and the length L of the cross flow fan11is slender, the circularity of the riveted metal vanes131will be affected, and the operation of the fan will become unsmooth, and thus such fan is not suitable to be installed in the panel meter of the fitness equipment. Although the problems created by the metal material and its rivet connection do not affect the usage of industrial products, yet the prior art is not suitable to be used in a panel meter installed with precision electronic components.

In view of the shortcomings of the prior art, the inventor of the present invention based on years of experience in the related industry to conduct extensive researches and experiments, and finally developed a stable cross flow fan for a fitness equipment to overcome the aforementioned shortcomings.

SUMMARY OF THE INVENTION

An object of the invention is to provide a cross flow fan structure wherein its housing and cross flow fan are made of a plastic material and skillfully assembled into a plastic cross flow fan module. The invention not only ensures a quick and convenient assemble, but also enhances the overall strength and the operation of the fan.

Another object of the invention is to provide a cross flow fan structure wherein the cross flow fan comes with a vibration resisting design for preventing vibrations and reducing noises, and thus the cross flow fan is applicable for fitness equipments.

In order to achieve the above-mentioned object, a cross flow fan structure in accordance with the invention includes:a) a housing integrally formed by plastic material in an injection molding process, the housing having a left side plate, a right side plate, and an L-shaped air deflector disposed between both side plates, the left side plate having a first mounting hole while the right side plate has a second mounting hole with a greater diameter, a flange being formed at the rim of the second mounting hole;b) a first damping/positioning body having a shaft sleeve and a cushioning rubber sleeve, the cushioning rubber sleeve enclosing the shaft sleeve in such a way that the mounting hole is exposed at the internal side of the first damping/positioning body, the cushioning rubber sleeve further having a ring groove for a practical installation of the cushioning rubber sleeve within the first mounting hole;c) a cross flow fan integrally formed by plastic material in an injection molding process, the left side of the cross flow fan having a metal shaft fitting into the shaft sleeve, the right side of the cross flow fan having a third mounting hole in axial direction;d) a second damping/positioning body made of rubber and tightly fitting into the third mounting hole of the cross flow fan, a flange being positioned at the external side of the second damping/positioning body while a mounting hole is provided in axial direction;e) a motor having a shaft holder and a projecting driving shaft at a end face thereof, at least one positioning hole being provided at both sides of the shaft holder;f) a mounting base having a mounting face disposed at the internal side thereof and corresponding to the flange of the second mounting hole, the external side of the mounting base having a ring seat with the same outer diameter of the motor for mounting the front part of the motor, the mounting face having a mounting hole at the center thereof for mounting the shaft holder of the motor in place, the periphery of the mounting hole having a locking hole corresponding to the positioning hole of the motor, the mounting base and the motor being secured together by screwing a screw through the locking hole into the positioning hole from the internal side toward the external side whereupon the mounting face of the mounting base is mounted on the flange by screwing a screw from the external side toward the internal side in place, the driving shaft of the motor being extended into the mounting hole of the second damping/positioning body in a tightly clamping state for driving the cross flow fan in rotational operation,
whereby a cross flow fan module made by plastic material is created.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

First of all, referring toFIGS. 4A,4B,5,6,7and8, a preferred embodiment in accordance with of the invention includes a housing50, a first damping/positioning body70, a cross flow fan60, a second damping/positioning body80, a motor90, and a mounting base100.

The housing50is integrally formed by plastic material in an injection molding process. The housing50includes a left side plate20, a right side plate30, and an L-shaped air deflector40disposed between both side plates. According to a preferred embodiment, the L-shaped air deflector40is formed in an arched shape for achieving a smooth flow guide. Moreover, a cross rib51is integrally formed at the front side of the L-shaped air deflector40between the left and right side plates20,30for strengthening the structure of the housing50. In addition, the left side plate20includes a first mounting hole21while the right side plate30has a second mounting hole31with a greater diameter. A flange32is formed at the rim of the second mounting hole31(seeFIGS. 6 through 8).

The first damping/positioning body70includes a shaft sleeve71and a cushioning rubber sleeve72. The cushioning rubber sleeve72encloses the shaft sleeve71in such a way that the mounting hole is exposed at the internal side of the first damping/positioning body70. The cushioning rubber sleeve72further includes a ring groove73for a practical installation of the cushioning rubber sleeve within the first mounting hole21.

The cross flow fan60is integrally formed by plastic material in an injection molding process. The left side of the cross flow fan60includes a metal shaft61fitting into the shaft sleeve71. The right side of the cross flow fan60includes a third mounting hole62in axial direction.

The second damping/positioning body80is made of rubber and tightly fits into the third mounting hole62of the cross flow fan60. A flange81is positioned at the external side of the second damping/positioning body80while a mounting hole82is provided in axial direction.

The motor90includes a shaft holder91and a projecting driving shaft92at an end face thereof. At least one positioning hole93is provided at both sides of the shaft holder91.

The mounting base100includes a mounting face101disposed at the internal side thereof and corresponding to the flange32of the second mounting hole31. The external side of the mounting base100includes a ring seat102with the same outer diameter of the motor90for mounting the front part of the motor. The mounting face101includes a mounting hole103at the center thereof for mounting the shaft holder91of the motor in place. The periphery of the mounting hole103includes a locking hole104corresponding to the positioning hole93of the motor90. The mounting base100and the motor90are secured together by screwing a screw105through the locking hole104into the positioning hole93from the internal side toward the external side. Thereafter, the mounting face101of the mounting base100is mounted on the flange32by screwing a screw106from the external side toward the internal side in place. Meanwhile, the driving shaft92of the motor90is extended into the mounting hole82of the second damping/positioning body80in a tightly clamping state for driving the cross flow fan60in rotational operation. In this way, a cross flow fan module200made by plastic material is created.

The housing50of the invention is integrally formed. As a result, it is not possible to fix the motor90from the internal side of the right side plate30. The mounting base100has to be attached to the motor90. Thereafter, the attached body is mounted on the flange32from the external side such that the driving shaft92of the motor90may properly fit into the mounting hole82of the second damping/positioning body80for bringing the cross flow fan60in rotational operation.

Moreover, a lateral fixing bar52is positioned between the bottom of the left side plate20and the bottom of the right side plate30. Both sides of the lateral fixing bar52are fixed by screws53between the left and right side plates20after the cross flow fan60is installed in the housing50. In this way, the whole structure of the housing50is strengthened.

A C-shaped indentation56is formed at the front and rear ends of the bottom of the left and right side plates20,30, respectively. A cushioning rubber pad55fits into the C-shaped indentation56. Besides, a sponge pad54is interposed between two cushioning rubber pads55at the front and rear sides of the left and right side plates20,30.

The mounting base100of the motor90includes more than one projecting ear108. The projecting ears108are fixed by screwing screws106into screw holes33at the periphery of the second mounting hole31.

Furthermore, the mounting base100includes a plurality of circulation holes107corresponding to cooling holes94at the internal sides of the motor for the circulation of air.

Based on the assembly of the above-mentioned components, the whole weight of the cross flow fan in accordance with the invention is much less than that of the conventional metal fan. However, the assembly structure is much stronger and the connecting way is much more convenient than the metal-riveting way. Therefore, an undesired deformation does not easily take place when the cross flow fan60is rotated in the direction of X-X (even if the length (L) of the cross flow fan60is slightly great). When the cross flow fan60is rotated in the direction of X-X, the shaft61is supported by the shaft sleeve71of the first damping/positioning body70. The rotational force received by the shaft sleeve71will be absorbed by the cushioning rubber sleeve72enclosing the shaft sleeve71. As a result, the rotational force is compensated for achieving an optimal damping effect. The more important is that the motor90is mounted by the mounting base100within the flange32of the flange32first. Thereafter, the driving shaft92is extended into the second damping/positioning body80to drive the cross flow fan60. A resonance will be created so as to cause a considerable vibration if the damping configuration is badly designed since the motor90is a power source. Thus, the motor90in accordance with the invention is fixed by use of the mounting base100first such that the driving shaft92is accurately aligned to the rotational axle x-x. In this way, an off-center drawback is avoided. In other words, an undesired vibration won't take place. Moreover, a windage resistance is minimized and since the cross flow fan60won't easily create deformation and a smooth operation is ensured. As a result, the noise caused by wind and jitter is eliminated. As shown inFIG. 10, the cross flow fan module200installed within the control panel201of a fitness equipment produces a gas flow field flowing from the wind outlet202to the operator such that the operator obtains a cool wind during the exercise session. It is very practical.