Cut for service motor with service ring

[0002] The subject invention relates generally to an improved casing assembly for a blower motor of a heating, venting, and air conditioning system for a motor vehicle. More specifically, the subject invention relates to an improved serviceability for a blower motor fully enclosed by the casing assembly.

[0003] A blower motor for a motor vehicle heating, venting, and air conditioning system (HVAC) includes a fan driveably affixed thereto. The blower motor is generally positioned inside the passenger compartment of the motor vehicle under the instrument panel. A blower casing assembly conceals the fan and channels air accelerated by the fan to the HVAC ducts, which route the air to various vents disposed about the passenger compartment. Generally, the casing encloses only the fan and not the motor. This exposes the motor to environmental contaminants generated by passengers, such as, for example, moisture, dirt, and physical contact.

[0004] A further deficiency of a casing covering only the fan is the inability of the casing to channel air from the fan to the motor for cooling the motor. This requires additional components such as hoses and supplemental casing to route cooling air from the fan to the motor. Casings have been designed that enclose both the motor and the fan, which overcome some of the deficiencies discussed herewith. However, a unitary casing of this design generates additional complications. For example, the unitary casing can inhibit access when attempting to perform service on the motor.

[0005] The blower motor can require service for such defects as generating excessive noise, not operating, or being jammed from debris entangled with the fan. Accessing a motor concealed within a unitary housing requires removal of the full casing, which is time consuming and costly. Frequently, the casing can be damaged during removal or reinstallation requiring replacement of the entire casing.

[0006] Therefore, a need exists for a blower motor casing that derives the benefits of a unitary design that encloses both the motor and the fan and also provides serviceable access to the motor and the fan.

[0007] A casing assembly for a blower motor of a heating, venting, and air conditioning system of a motor vehicle includes a fan chamber for housing a blower fan and a motor chamber for housing the blower motor. An air conduit channels air from the fan chamber to the motor chamber. A panel connects the fan chamber to the motor chamber. The panel includes a groove circumscribing the motor chamber for separating the motor chamber from the assembly. The groove can be pierced for cutting a ring around the motor chamber for removing the motor and the fan for service. The assembly includes a band for reconnecting the separated motor chamber to the assembly.

[0008] The casing assembly of the subject invention resolves the deficiencies of the prior art by providing a unitary design with serviceable features. The unitary design of the subject invention encloses both the fan and the motor protecting the motor from environmental contaminants. Further, an air conduit can be molded integrally with the casing eliminating the need for supplemental casing and a hose for routing cooling air to the motor from the fan. This concept provides cost and mass reduction to the (HVAC) system.

[0009] Piercing the groove provides a method of accessing the motor and the fan for service in a time and cost efficient manner by eliminating the need for removing the entire casing. Further, providing a band for reconnecting the motor chamber to the assembly provides for the reuse of the motor chamber after the motor has been serviced or replaced. This reduces the service cost in two ways. By reusing the motor chamber eliminates the need for purchasing a new casing assembly after servicing. Further shipping and storage costs for the band are much lower than for a replacement casing assembly due to the band's substantially two dimensional geometry as opposed to the casing's three dimensional geometry

[0010] Other advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:

[0011] FIG. 1 is an exploded view of the subject invention;

[0012] FIG. 2 is a side sectional view of the groove of the subject invention;

[0013] FIG. 3 is an exploded view of the subject invention showing the motor housing separated from the fan housing;

[0014] FIG. 4 is a sectional view of the subject invention showing the band reconnecting the motor housing to the fan housing;

[0015] FIG. 5 is a top view of the subject invention; and

[0016] FIG. 6 is a sectional view of the subject invention through line 6—6 of FIG. 5.

[0017] Referring to FIG. 1, a casing assembly for a blower motor of a heating, venting, and air conditioning system (HVAC) of a motor vehicle is generally shown at 10. The assembly 10 includes a fan chamber 12 for housing a blower fan 14 and a motor chamber 16 for housing the blower motor 18. The fan 14 is driveably attached to the motor 18 via a drive shaft 20. The blower motor 18 is activated to circulate air throughout the passenger compartment of the motor vehicle via HVAC air ducts (not shown). An air channel 22 funnels air accelerated by the fan 14 from the assembly 10 to the HVAC ducts.

[0018] A panel 24 connects the fan chamber 12 to the motor chamber 16. The panel 24 includes a groove 26 that circumscribes the motor chamber 16 for separating the motor chamber 16 from the assembly 10 as will be explained further hereinbelow. The panel 24 further includes webbing 28 for strengthening the assembly 10.

[0019] As best shown in FIG. 2, the groove 26 includes a base 30, which is pierceable for separating the motor chamber 16 from the assembly 10. During a service procedure, the base 30 can be pierced with a razor or equivalently sharp instrument for cutting a ring 32 into the groove 26 circumscribing the motor chamber 16. In the preferred embodiment, the base 30 is molded from the same materials as the assembly 10, however, it is understood by the inventor that the base 30 could be molded from a more pliant material that would be more easily pierced. The more pliant base 30 is affixed to the assembly 10 by insertion into a mold tool prior to injecting the assembly 10 material. The assembly 10 material of the subject invention is contemplated to be a talc or glass filled polypropylene, or an equivalent.

[0020] As best represented in FIG. 5, the groove 26 is oriented in a non-symmetrical spatial relationship with the motor chamber 16. Therefore, the ring 32 is cut into the base 30 in an offset spatial relationship to the motor chamber 16. The intent of the offset is to reduce the possibility of damaging the fan 14 with the piercing tool. Due to the offset the groove 26 the ring 32. The intersects the fan 14 only twice, as opposed to tracing the fan 14, for reducing the probability of contact between the fan 14 and the piercing tool.

[0021] Pursuant to cutting the ring 32 into the assembly 10, the motor chamber 16 can be extracted from the casing assembly 10. Because the fan 14 is offset from the ring 32, the fan 14 and the ring 32 must be oriented for extracting the fan 14 and the motor 18. Once oriented, the fan easily slide out of the assembly 10 through an opening 34 formed by the ring 32.

[0022] As seen in FIGS. 1 and 3, an air conduit 36 is molded integrally with the assembly 10 for cooling the motor. The conduit 36 connects the fan chamber 12 to the motor chamber 16 for channeling cooling air from the fan chamber 12 to the motor chamber 16. The motor chamber 16 includes at least one vent 37 for venting cooling air out of the motor chamber 16. Molding the conduit 36 integrally with the assembly 10 eliminates the need for adding a cooling tube to the assembly 10 as is currently practiced.

[0023] The motor chamber 16 includes an inner surface 39. The inner surface 39 includes at least one catch 41 for securing the motor 18 within motor chamber 16. The sectional view in FIG. 6 shows the catch 41 formed as a series of ramps decreasing the volume within the motor chamber 16 for creating a press fit condition between the motor chamber 16 and the motor 18. The press fit condition secures the motor 18 within the chamber and still allows the motor to be easily removed from the motor chamber 16 for service or replacement.

[0024] The motor chamber 16 includes an electrical inlet 43 for providing electrical access to the motor. As shown in FIG. 1, the motor includes an electrical connector 45 aligning with the electrical inlet 43. In installed position, an electrical wire harness (not shown) includes an appendage having an electrical connector disposed at the end thereof that plugs into the electrical inlet 43. The same appendage can include a second electrical connector for connecting to a blower motor 18 speed control (not shown) attached to the assembly 10 in a slot 47 located in the air channel 22.

[0025] Referring to FIGS. 3 and 4, the assembly 10 includes a band 38 for reconnecting the extracted motor chamber 16 to the assembly 10. Subsequent to repairing or replacing the motor 18, the motor 18 is re-inserted into the motor chamber 16. The extracted motor chamber 16 having the repaired blower motor 18 secured therein is re-aligned with the ring 32 cut into the casing assembly 10. The webbing 28 includes an alignment wall 29 for aligning the band 38 with the groove 26, and for aligning the band 38 over the ring 32 to secure the extracted motor chamber 16 to the casing assembly 10. The band 38, in the preferred embodiment, is formed from steel or an equivalently rigid material for supporting the reconnected motor chamber 16 and the assembly 10.

[0026] The band 38 includes a plurality of apertures 40 for receiving fasteners 42. The assembly 10 includes a plurality of bosses 44 aligning with the apertures 40 for securing the band 38 to the assembly 10 with the fasteners 42. The bosses 44 are arranged concentrically on each side of the groove 26. A first concentric arrangement of bosses 44 is disposed upon the assembly 10. A second concentric arrangement of bosses 44 is disposed upon the extracted motor chamber 16. Therefore, the band 38, having received the fasteners 42, re-attaches the extracted motor chamber 16 to the assembly 10.

[0027] Prior to affixing the band 38 to the assembly 10, the ring 32 is sealed for preventing air from escaping from the casing assembly 10 and for preventing moisture from entering the casing assembly 10. The seal 46 of the preferred embodiment as shown in the FIGS. 4 through 7 is a viscous sealing material extruded into the groove 26, prior to aligning the band 38 over the ring 32. It is, however, understood that a flexible, solid seal 46 could be affixed to the band 38 for sealing the entire groove 26, and therefore, preventing the air or moisture from passing through the ring 32.

[0028] The invention has been described in an illustrative manner, and it is to be understood that the terminology which has been used is intended to be in the nature of words of description rather than of limitation.

[0029] Many modifications and variations of the present invention are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims, wherein reference numerals are merely for convenience and are not to be in any way limiting, the invention may be practiced otherwise than as specifically described.