Pilot and Detent Apparatus for a Vacuum Device

The present invention relates to an apparatus for facilitating the assembly of a vacuum device.

A vacuum device, such as a wet/dry vacuum cleaner, may include, for example, a motor housing, a lid cage, and a tank. The motor housing houses a motor which drives an impeller to create a vacuum for the vacuum device. The lid cage includes a filter cage that holds a filter which filters the air moving through the vacuum device in response to the vacuum created by the impeller.

During assembly of the vacuum device, the motor and impeller are inserted into the motor housing, and the motor housing is attached to the lid cage so that the motor and impeller are clamped therebetween. The lid cage has clamps for clamping the motor housing and lid cage to the tank of the vacuum device.

The motor housing is normally attached to the lid cage by way of screws, bolts, or other fasteners that are fitted through corresponding holes in the motor housing and the lid cage. For ease of assembly, it is important that the motor housing and the lid cage properly seat together so that the corresponding holes in the motor housing and in the lid cage properly align. If these holes properly align, the fasteners may be easily applied in order to secure the motor housing and the lid cage to one another. The present invention is directed to an apparatus which facilitates proper seating between the motor housing and the lid cage of a vacuum device so that the motor housing and the lid cage may be properly and easily secured to one another.

In accordance with one aspect of the present invention, a vacuum apparatus comprises a holding tank for holding debris picked up by the vacuum apparatus, a lid cage for holding a filter, a motor housing for housing a motor as a source of vacuum, attaching means for attaching the lid cage and the motor housing to the holding tank, and a detent cooperating with the motor housing and the lid cage for providing an indication to an assembler that the lid cage and the motor have been properly seated with respect to one another.

In accordance with another aspect of the present invention, a vacuum apparatus comprises a holding tank for holding debris picked up by the vacuum apparatus, a lid cage for holding a filter wherein the lid cage has an attaching mechanism for attaching the lid cage to the holding tank, a motor housing attachable to the lid cage, a detent cooperating with the motor housing and the lid cage for providing an indication to an assembler that the lid cage and the motor have been properly seated with respect to one another, and a pilot for guiding relative movement between the lid cage and the motor housing in order to facilitate the indication provided by the detent that the lid cage and the motor have been properly seated.

In accordance with yet another aspect of the present invention, a subassembly for a vacuum apparatus comprises a lid cage for holding a filter, a motor housing attachable to the lid cage, and a detent cooperating with the motor housing and the lid cage for providing an indication to an assembler that the lid cage and the motor housing have been properly seated with respect to one another.

These and other features and advantages will become more apparent from a detailed consideration of the invention when taken in conjunction with the drawings in which:

FIG. 1 is an elevational side view of a vacuum device incorporating the present invention;

FIG. 2 is an elevational top view of the motor housing and motor of the vacuum device of FIG. 1 with the cover of the vacuum device removed;

FIG. 3 is a partial sectional view, taken generally along the lines 3--3, of FIG. 2;

FIG. 4 is an sectional side view of a lid cage configured in accordance with the present invention;

FIG. 5 is an elevational top view of the lid cage configured in accordance with the present invention;

FIGS. 6 and 7 show exemplary dimensions for the detents on the lid cage shown in FIG. 5;

FIG. 8 is an elevational bottom view of the motor housing shown in FIG. 1; and,

FIG. 9 is an elevational bottom view of the motor and impeller in the motor housing shown in FIG. 8.

As shown in FIGS. 1-3, a vacuum device 20, such as a wet/dry vacuum cleaner, includes a tank 22, a lid cage 24, a motor housing 26 having a side wall 26a and an internal surface 26b, and a cover 28. The vacuum device may have a vacuum inlet for admitting air into the vacuum device 20 and a vacuum outlet for expelling air from the vacuum device 20. The tank 22, the lid cage 24, the motor housing 26, and the cover 28 may each be formed of a suitable material such as molded plastic. The lid cage has a plurality of clamps 30 in order to secure the lid cage 24, the motor housing 26, and the cover 28 to the tank 22. The cover 28 has a side wall 32 and a top surface 34 to which a handle 36 is affixed by a pair of screws 38. The screws 38 extend through a pair of clearance apertures 40 at opposite ends of the handle 36 and a pair of clearance apertures 42 in the top surface 34 of the cover 28. The screws 38 are threadably received in a pair of upwardly facing bores 44 formed integrally with the motor housing 26. Accordingly, the motor housing 26 supports the cover 28.

As shown in FIGS. 2, 3, and 9, disposed within the motor housing 26 is a motor subassembly 46 having an electric motor 46a and an impeller which is within an impeller cover 46b and which is drivingly connected to the electric motor 46a in order to create a vacuum for the vacuum device 20. For clarity, the motor subassembly 46 is not fully shown in section in the drawings.

As shown in FIGS. 2, 3, and 8, the motor housing 26 has a first neck 50 for receiving a vertical surface 52 of the electric motor 46a. The first neck 50 has a pair of opposing flat regions 50a and 50b which mate with corresponding flat regions 52a and 52b of the vertical surface 52 of the electric motor 46a. The first neck 50 also has a slot 50c for receiving a terminal 54 of the electric motor 46a, and a plurality of ribs 56 which act to limit movement of the motor subassembly 46 when the motor subassembly 46 is contained between the motor housing 26 and the lid cage 24. The slot 50c and the opposing flat regions 50a and 50b allow the motor subassembly 46 to be inserted into the motor housing 26 in a preferred orientation.

As further shown in FIGS. 3 and 8, the motor housing 26 has a plurality of internally threadable bosses 58a-58e and 60. The internally threadable bosses 58a-58e are at least partially supported by a pilot guide wall 62. As will be discussed below more fully, at least some of the internally threadable bosses 58a-58e and 60 are arranged to align with corresponding holes in the lid cage 24 which has the clamps 30 and which is positioned between the tank 22 and the motor housing 26. The motor housing 26 has a second neck 64 which acts as a clamping surface for clamping the motor subassembly 46 to the lid cage 24. Accordingly, the second neck 64 of the motor housing 26 engages a circular surface 66 of the impeller cover 46b of the motor subassembly 46.

FIG. 9 shows the motor subassembly 46 and the motor housing 26 after the motor subassembly 46 has been inserted into the motor housing 26. When assembled, a pilot guide slot 68 is formed between motor subassembly 46 (particularly the impeller cover 46b) and the pilot guide wall 62 (also see FIG. 3). As shown in FIG. 9, the pilot guide slot 68 is curved. More specifically, the pilot guide slot 68 is semi-circular.

The lid cage 24, as shown in FIGS. 4 and 5, has a filter cage 70 which holds a filter of the vacuum device 20. The lid cage 24 also has a bearing surface 72 which supports the motor subassembly 46 and the motor housing 26. An opening 74 through the bearing surface 72 permits a filter to be inserted into the filter cage 70. The bearing surface 72 also has a plurality of holes 76, 78, 80, 82, and 84 which, when the motor housing 26 seats properly upon the lid cage 24, are aligned for receiving fasteners in order to affix the motor housing 26 and the lid cage 24 together.

A recess 86 in the bearing surface 72 forms a bearing ledge 88 which engages a lower surface 90 (FIG. 3) of the impeller cover 46b of the motor subassembly 46 when the motor housing 26 and the motor subassembly 46 are seated on the lid cage 24. Consequently, the bearing ledge 88 of the bearing surface 72 of the lid cage 24 supports the motor subassembly 46 when the motor subassembly 46 and the motor housing 26 are properly brought into contact with the bearing surface 72 of the lid cage 24. When the motor subassembly 46 and the motor housing 26 are brought into contact with the bearing surface 72 of the lid cage 24, the lower part of the impeller cover 46b protrudes into the filter cage 70.

As shown in FIG. 5, the bearing surface 72 of the lid cage 24 has a pair of detents 92 and 94 which project upwardly therefrom and which cooperate with the internally threadable bosses 58a and 58e, respectively, of the motor housing 26. The bearing surface 72 also has a pilot 96. As shown in FIGS. 4 and 5, the pilot 96 is a curved projection. More specifically, the pilot 96 is a semi-circular projection extending upwardly from the bearing surface 72.

During assembly of the vacuum device 20, (a) the assembler attaches the handle 36 and the cover 28 to the motor housing 26 by use of the screws 38, (b) the assembler inserts the assembled handle 36, cover 28, and motor housing 26 into a clamping fixture for holding these parts during further assembly, (c) the assembler inserts the motor subassembly 46 into the motor housing 26, and (d) the assembler applies the bearing surface 72 to the motor subassembly 46 and the motor housing 26 (i) so that the internal surface 26b of the motor housing 26 faces the bearing surface 72, (ii) so that the pilot 96 enters the pilot guide slot 68 formed between the impeller cover 46b and the pilot guide wall 62, (iii) so that, when the pilot 96 is fully inserted into the pilot guide slot 68, the side wall 26a, the internally threadable bosses 58a-58e, and the pilot guide wall 62 contact the bearing surface 72, and (iv) so that, as the lid cage 24 is viewed in FIG. 5, the internally threadable boss 58a is just below the detent 92 and the internally threadable boss 58e is just above the detent 94.

The assembler then rotates the lid cage 24 with respect to the motor subassembly 46 and the motor housing 26. As the lid cage 24 rotates with respect to the motor subassembly 46 and the motor housing 26, the pilot 96 guides this rotation and maintains the relative positions between the motor housing 26 and the lid cage 24. When the lid cage 24 has been rotated sufficiently with respect to the motor subassembly 46 and the motor housing 26, the internally threadable boss 58a engages a rounded corner 92a of the detent 92, and the internally threadable boss 58e engages a rounded corner 94a of the detent 94. Accordingly, the detents 92 and 94 offer a small resistance to the rotation of the motor cover 26 with respect to the lid cage 24.

Upon further rotation of the lid cage 24 with respect to the motor subassembly 46 and the motor housing 26, this small resistance is overcome, the internally threadable boss 58a snaps into a rounded recess 92b of the detent 92 and comes to rest against an inner radius of the detent 92, and the internally threadable boss 58e snaps into a rounded recess 94b of the detent 94 and comes to rest against an inner radius of the detent 94. This detent action, i.e., the initial resistance to rotation and then the snapping of the internally threadable bosses 58a and 58e into their corresponding detents 92 and 94, indicates to the assembler that the internally threadable bosses 58a-58e of the motor housing 26 and the holes 76-84 of the lid cage 24 are properly aligned to receive fasteners. This alignment is also aided by the pilot 96 interacting with the pilot guide slot 68. Preferably, although not essentially, only the outer surface of the pilot 96 interacts with the pilot guide slot 68.

When rotation ceases because the internally threadable boss 58a fully engages the inner radius of the detent 92 and the internally threadable boss 58e fully engages the inner radius of the detent 94, the internally threadable boss 58b of the motor housing 26 aligns with the hole 76 of the lid cage 24, the internally threadable boss 58a of the motor housing 26 aligns with the hole 78 of the lid cage 24, the internally threadable boss 60 of the motor housing 26 aligns with the hole 80 of the lid cage 24, the internally threadable boss 58e of the motor housing 26 aligns with the hole 82 of the lid cage 24, and the internally threadable boss 58d of the motor housing 26 aligns with the hole 84 of the lid cage 24. Fasteners, such as threaded screws, may then be inserted through the holes 76, 78, 80, 82, and 84 and turned into the corresponding internally threadable bosses 58b, 58a, 60, 58e, and 58d. As the threaded screws are turned, they cut threads into the internally threadable bosses 58b, 58a, 60, 58e, and 58d and are held therein. The motor housing 26 and the lid cage 24 are then set on the tank 22 with the filter cage 74 protruding therein, and the clamps 30 are used to clamp the motor housing 26 and the lid cage 24 to the tank 22.

Furthermore, the pilot 96 acts as a noise seal between the interior of the motor housing 26 and the exterior of the vacuum device 20.

FIG. 6 shows exemplary dimensions for the detent 92. The 3.737 radius of the detent 92 is with respect to the center of the opening 74 of the filter cage 70. The detent 92 has an entrance angle .alpha. with respect to a vertical center line 100 of about 60.degree., and subtends an angle .beta. of about 120.degree..

FIG. 7 shows exemplary dimensions for the detent 94. The 3.737 radius of the detent 94 is with respect to the center of the opening 74 of the filter cage 70. The detent 92 has an entrance angle .theta. with respect to a vertical center line 102 of about 0.degree., and subtends an angle .phi. of about 150.degree..

The internally threadable bosses 58a and 58e may be 3.139 along a line which is perpendicular to a line extending between the internally threadable bosses 58c and 60 and through a center 98 of the impeller cover 46b. The intersection between the line extending between the internally threadable bosses 58c and 60 and a line between the internally threadable bosses 58a and 58e is 1.813 from the center 98 of the impeller cover 46b as viewed in FIG. 9. Accordingly, the internally threadable bosses 58a and 58e are on a radius of 3.625 from the center 98 of the impeller cover 46b as viewed in FIG. 9. The internally threadable bosses 58a and 58e may have an outer diameter of 0.38, and the radius of the pilot guide wall 62 may be 3.44. The above dimensions may be in inches. With these exemplary dimensions and the exemplary dimensions of the detents 92 and 94 of the lid cage 24, the proper detent action is obtained even if there is some dimensional variation introduced, for example, during molding or modeling.

The foregoing description is for the purpose of teaching those skilled in the art the best mode of carrying out the invention and is to be construed as illustrative only. Many modifications and alterations can be made without departing from the invention. For example, the dimensions given above are by way of example only and may be varied without departing from the scope of the present invention. Also, the motor housing 26 and the cover 28 may be a single molded part instead of separate molded parts. Accordingly, it is intended that all such modifications and alterations be considered within the spirit and scope of the invention as defined in the attached claims.