[0002] The present invention relates to condensing units, and in particular to an attachment
technique for fixing the condenser or other components to the condensing unit base
plate.
[0003] Condensing units are self-contained units typically comprising a hermetic compressor,
condenser and cooling fan all mounted to a base plate and having refrigerant lines
adapted for connection to a remotely located expansion valve and evaporator. In the
past, the condenser has been attached to the base plate by means of removable fasteners,
such as bolts or threaded studs that extend through openings in the base plate and
are secured by means of nuts and washers fastened from underneath the base plate.
This not only increases the parts count for the condensing unit but increases assembly
time due to the necessity of attaching the various fasteners.
[0004] In the present invention, the condenser or other component is attached to the base
plate by means of integral torque tabs that are twisted underneath the base plate
to draw the condenser or other component downwardly against the upper surface of the
base plate. In a preferred embodiment, the torque tabs are located on the lower ends
of the condenser or other component end plates. The tabs are preferably designed to
be machine twisted to provide enough holding force to maintain the condenser or other
component and base plate in a rigid condition.
[0005] In one form thereof, the present disclosure provides a condensing unit, including
a base plate having a plurality of components mounted on an upper surface thereof,
the components including a compressor and a condenser. At least one of the components
includes a plurality of tabs extending through a corresponding plurality of slots
in the base plate. The tabs include distal portions that are twisted underneath the
base plate, and the tab distal portions include respective camming surfaces that tightly
engage an undersurface of the base plate to tightly fix the at least one component
to the upper surface of said base plate. In a preferred embodiment, the condensing
unit includes a base plate having a condenser mounted on an upper surface thereof,
the condenser including a plurality of tabs extending through a corresponding plurality
of slots in the base plate.
[0006] In another form thereof, the present disclosure provides a condensing unit including
a base plate having an undersurface and a condenser mounted on an upper surface thereof,
the condenser including one or more attachment elements extending through one or more
corresponding attachment receiving means in the base plate. The one or more attachment
elements include means for engaging the base plate such that, upon deformation, the
one or more attachment means tighten against the undersurface of the base plate.
[0007] In yet another form thereof, the present disclosure provides a method of attaching
a condenser of a condensing unit to a base plate of the condensing unit, the method
including the step of positioning the condenser to abut a base plate, the condenser
having a plurality of tabs, each tab having an internal distal upper edge, and the
base plate having an undersurface. The method further includes the step of aligning
each tab with a corresponding slot on the base plate. The method further includes
the steps of inserting each tab through the corresponding slot one the base plate
such that each tab extends through the corresponding slot, and then twisting each
tab to thereby draw the internal distal upper edge of each tab tightly against the
undersurface of the base plate such that the condenser is locked to the base plate.
[0008] The above-mentioned and other features and advantages of this invention, and the
manner of attaining them, will become more apparent and the invention itself will
be better understood by reference to the following description of an embodiment of
the invention taken in conjunction with the accompanying drawings, wherein:
[0009] Fig. 1 is a plan view of a condensing unit incorporating the attachment mechanism
of the present invention;
[0010] Fig. 2 is a side elevational view of the condensing unit;
[0011] Fig. 3 is a perspective view of the condenser;
[0012] Fig. 4 shows a side elevational perspective view of the assembled condenser and base
plate wherein the tabs are in their pre-twisted state;
[0013] Fig. 5 shows a distal plan view of the assembled condenser and base plate wherein
the tabs are in their pre-twisted state;
[0014] Fig. 6 shows a side elevational view of the assembled condenser and base plate wherein
the tabs are in their pre-twisted state;
[0015] Fig. 7 shows a side elevational view of one of the end plates of the condenser;
[0016] Fig. 8 shows an internal side view of one of the end plates showing an internal surface
with open, unbent flanges;
[0017] Fig. 9 is a perspective view of the base plate;
[0018] Fig. 10 is a perspective internal side view of one of the base plates;
[0019] Fig. 11 is an internal side view of one of the end plates showing an internal surface
with bent flanges;
[0020] Fig. 12 shows views of one of the end plates of the condenser showing the tabs in
detail;
[0021] Fig. 13 shows a perspective view of the condenser and base plate wherein the tabs
have been twisted to their locked position; and
[0022] Fig. 14 is a fragmentary elevational side end view of one of the plates and the base
plate, showing the tabs twisted to their locked position;
[0023] Fig. 15 is a fragmentary elevational distal plan view from underneath the base plate
showing a tab twisted to its locked position;
[0024] Fig. 16 is an enlarged elevational view of the base plate and end plate wherein the
tabs are in their pre-twisted state; and
[0025] Fig. 17 is an enlarged perspective view of the end plate and base plate with the
tabs in their pre-twisted state.
[0026] Corresponding reference characters indicate corresponding parts throughout the several
views. The exemplification set out herein illustrates one exemplary embodiment of
the invention, in one form, and such exemplification is not to be construed as limiting
the scope of the invention in any manner.
[0027] With reference to Figs. 1 and 2, an exemplary condensing unit 10 is shown. It comprises
a metal base plate 12 having flanges 14 and an upper surface 16 to which are mounted
a hermetic compressor 18, receiver 20 and a condenser unit 22, the latter comprising
a condenser 24 and a fan assembly 26. Fan assembly 26 comprises a plastic housing
or shroud 36 which houses motor driven fan 38. The discharge line 28 from compressor
18 is connected to inlet 29 of the condenser 24 and outlet 31 thereof is connected
by means of tube 30 to receiver 20. Inlet and outlet ports 32 and 34, respectively,
are adapted to be connected to the evaporator unit (not shown) of the refrigeration
system.
[0028] Referring now to Fig. 3, condenser 24 comprises a pair of end plates 40 and 42, a
serpentine coil 44 carrying a refrigerant connected to the inlet 29 and outlet 31
and in good thermal connection with a plurality of cooling fins 46 in a manner well
known in the art. Coil 44 includes internal portions 47 and external portions 49.
[0029] Exterior surface 41 of end plate 42 is shown in Fig. 3. Fig. 12 illustrates interior
surface 43 of end plate 42 in detail. End plate 42 is made of a stamped and bent piece
of sheet metal, for example 18 Ga. galvanized steel, having flanges 48 and a plurality
of openings 50 through which serpentine coils 44 extend as shown in Fig. 3. As further
shown in Fig. 3, flanges 48 of end plate 42 are bendable to extend outwardly from
exterior surface 41, and away from the plurality of cooling fins 46, such that a portion
of flanges 48 remains adjacent to exterior surface 41. The pair of end plates 40 and
42 may further include attachment means extending from lower end 45 of each end plate
40 and 42, respectively, that includes tabs or similar structures to attach condenser
24 to base plate 12 by receipt through attachment receiving means in base plate 12,
such as correspondingly shaped structural openings or slots 74 (Fig. 9).
[0030] As shown in Fig. 12, at lower end 45 of end plate 42 are a pair of tabs 52 and 54
that join the main body 56 of end plate 42 through connecting areas 58 and 60 formed
by notches 62 that are oriented at an angle α of, for example, 10 degrees relative
to side edges 64 such that internal distal upper edges 66 of notches 62 are disposed
at the same angle α relative to lower edges 68. Each internal distal upper edge 66
acts as a camming surface for each tab 52 and 54 when tabs 52 and 54 are received
into slots 74 of base plate 12 and deformed or bent to lock condenser 24 to base plate
12. Each tab 52 and 54 additionally includes a side edge 65. Each tab 52 and 54 further
includes an internal lateral edge 59 and an internal proximal edge 61 that, together
with internal distal upper edge 66, defines notch 62. Left hand end plate 40 is identically
constructed except that it is a mirror image.
[0031] Figs. 7 and 8 illustrate interior surface 43 of end plate 42 including a plurality
of openings 50, lower end 45, the pair of tabs 52 and 54, and flanges 48. Flanges
48 are shown positioned in first, outwardly bent position (Fig. 7) and a second, unbent
open position (Fig. 8). Figs. 10 and 11 show interior surface 43 of end plate 40 with
a plurality of openings 50, a pair of side edges 64, main body 56, a pair of tabs
52 and 54, a lower end 45, and flanges 48 positioned in first, outwardly bent position.
[0032] Referring back to Fig. 3, serpentine coil 44 includes segments that are folded back
and forth and extend through apertures 50 of end plates 40 and 42, where the segments
of serpentine coil 44 have internal portions 47 that are positioned between the pair
of end plates 40 and 42. Further, the segments of coil 44 include external portions
49 that are positioned outside external surfaces 41 of end plates 40 and 42, respectively.
[0033] Fig. 4 shows condenser 24 being placed on upper surface 16 of base plate 12 with
tabs 52 and 54 extending through slots 74 (Fig. 9) of base plate 12 as shown in the
lower left hand view of the assembled condenser and base plate as viewed from underneath
with the lower surface of the base plate being visible. Tabs 54 and 52 and slots 74
in base plate 12 are aligned so that condenser 42 can simply be dropped in place on
base plate 12 and the tabs 52 and 54 will be inserted into and extend through slots
74 as shown in the lower left hand views of Figs. 4 and 6, and in the distal plan
view of Fig. 5.
[0034] Tabs 52 and 54 are then twisted by means of a suitable machine and due to the orientation
of notches 62 and internal distal upper edges 66 (Fig. 16), such twisting action will
cause distal portions of tabs 52 and 54, defined by side edge 65 and lower edge 68
of each tab 52 and 54, to bend about bending axis x-x (Fig. 17) so that internal distal
upper edges 66 of tabs 52 and 54 will be tightly drawn against the underneath surface
72 of base plate 12 and very firmly lock condenser 24 in place.
[0035] As shown in Fig. 17, internal distal upper edge 66 includes a sloped, non-orthogonal
plane relative to base plate 12 to allow for a complete geometric tolerance range
of tabs 52 and 54 of end plate 42 when tabs 52 and 54 are inserted into slots 74 in
base plate 12. Contact point A is positioned between base plate 12 and a surface of
internal distal upper edge 66. Bending will occur along axis x-x that passes through
contact point A and lies on plane AA. Plane AA is the plane with a minimum resistance
against bending force P that is applied by the twisting machine (not shown). As shown
in Fig. 16 and, in particular, Fig. 17, the inclined surfaces of internal distal upper
edges 66 as tabs 52 and 54 are bent rearwardly exert a type of camming action against
the lower surface of base plate 12 that pulls end plates 40 and 42 against the upper
surface of base plate 12 to lock condenser 24 against base plate 12. Figs. 13 and
15 illustrate distal plan views of condenser 24 attached to base plate 12 showing
internal distal upper edges 66 bent and twisted into a locked position, where Fig.
15 shows a rearward bend and Fig. 13 shows an alternative frontward (or forward) bend.
Fig. 14 shows external surface 41 of end plate 40 from an elevational side view showing
tabs 52 and 54 similarly bent and twisted into a locked position.
[0036] While this invention has been described as having a preferred design, the present
invention can be further modified within the spirit and scope of this disclosure.
This application is therefore intended to cover any variations, uses, or adaptations
of the invention using its general principles. Further, this application is intended
to cover such departures from the present disclosure as come within known or customary
practice in the art to which this invention pertains and which fall within the limits
of the appended claims.
1. A condensing unit (22), comprising:
a base plate (12) having a plurality of components mounted on an upper surface (16)
thereof, said components including a compressor (18) and a condenser (24);
at least one of said components including a plurality of tabs (52, 54) extending through
a corresponding plurality of slots (74) in said base plate (12);
said tabs (52, 54) including distal portions (65, 68) that are twisted underneath
said base plate (12), said tab distal portions (65, 68) including respective camming
surfaces (66) that tightly engage an undersurface (72) of said base plate (12) to
tightly fix said at least one component to the upper surface (16) of said base plate.
2. The condensing unit (22) of claim 1, wherein said at least one of said components
is a condenser (24) that comprises a pair of end plates (40, 42) having a plurality
of apertures (50), a pair of side edges (64), and a lower end (45), said plurality
of tabs (52, 54) extending from said lower end (45) of each of said end plates (40,
42).
3. The condensing unit (22) of claim 2, wherein said condenser (24) further comprises:
a coil (44) extending through said plurality of apertures (50) of said pair of end
plates (40, 42).
4. The condensing unit (22) of claim 1, wherein each said camming surface (66) comprises
an internal distal upper edge (66), and each tab (52, 54) further includes an internal
proximal edge (61) and an internal lateral edge (59), said internal proximal edge
(61), said internal lateral edge (59), and said internal distal upper edge (66) defining
a notch (62).
5. The condensing unit (22) of claim 4, wherein said internal distal upper edge (66)
and said internal lateral edge (59) are oriented non-orthogonally relative to said
base plate undersurface (72) at a given angle (α).
6. The condensing unit (22) of claim 5, wherein said given angle (α) is 10 degrees.
7. The condensing unit (22) of claim 1, wherein at least one of said tabs (52, 54) further
includes a side edge (65) and a lower edge (68), wherein at least one of said distal
portions (65, 68) is defined by said lower edge (68) and said side edge (65).
8. A condensing unit (22), comprising:
a base plate (12) having a condenser (24) mounted on an upper surface (16) thereof,
said condenser (24) including a plurality of tabs (52, 54) extending through a corresponding
plurality of slots (74) in said base plate (12);
said tabs (52, 54) including distal portions (65, 68) that are twisted underneath
said base plate (12), said tab distal portions (65, 68) including respective camming
surfaces (66) that tightly engage an undersurface (72) of said base plate (12) to
tightly fix said condenser (24) to the upper surface (16) of said base plate (12).
9. The condensing unit (22) of claim 8, wherein said condenser (24) further comprises
a pair of end plates (40, 42) having a plurality of apertures (50), a pair of side
edges (64), and a lower end (45), said plurality of tabs (52, 54) extending from said
lower end (45) of each of said end plates (40, 42).
10. The condensing unit (22) of claim 9, wherein said condenser (24) further comprises
a coil (44) extending through said plurality of apertures (50) of said pair of end
plates (40, 42).
11. The condensing unit (22) of claim 8, wherein each of said camming surfaces (66) comprises
an internal distal upper edge (66), and each tab (52, 54) further includes an internal
proximal edge (61) and an internal lateral edge (59), said internal proximal edge
(61), said internal lateral edge (59), and said internal distal upper edge (66) defining
a notch (62).
12. The condensing unit (22) of claim 11, wherein said internal distal upper edge (66)
and said internal lateral edge (59) are oriented non-orthogonally relative to said
base plate undersurface (72) at a given angle (α).
13. The condensing unit (22) of claim 12, wherein said given angle (α) is 10 degrees.
14. The condensing unit (22) of claim 8, wherein at least one of said tabs (52, 54) further
includes a side edge (65) and a lower edge (68), wherein at least one of said distal
portions (65, 68) is defined by said lower edge (68) and said side edge (65).
15. A condensing unit (22) comprising:
a base plate (12) having an undersurface (72) and a condenser (24) mounted on an upper
surface (16) thereof, said condenser (24) including one or more attachment elements
(52, 54) extending through one or more corresponding attachment receiving means (74)
in said base plate (12); and
said one or more attachment elements (52, 54) including means for engaging said base
plate (12) such that, upon deformation, said one or more attachment means (52, 54)
tighten against said undersurface (72) of said base plate (12).
16. The condensing unit (22) of claim 15, said condenser (24) further comprising a pair
of end plates (40, 42) having a lower end (45), wherein said pair of attachment elements
(52, 54) extends from said lower end (45) of each of said end plates (40, 42).
17. A method of attaching a condenser of a condensing unit (22) to a base plate (12) of
the condensing unit (22), the method comprising the steps of:
positioning the condenser (24) to abut a base plate (12), the condenser (24) having
a plurality of tabs (52, 54), each tab (52, 54) having an internal distal upper edge
(66), and the base plate (12) having an undersurface (72);
aligning each tab (52, 54) with a corresponding slot (74) on the base plate (12);
inserting each tab (52, 54) through the corresponding slot (74) on the base plate
(12) such that each tab (52, 54) extends through the corresponding slot (74);
then twisting each tab (52, 54) to thereby draw the internal distal upper edge (66)
of each tab (52, 54) tightly against the undersurface (72) of the base plate (12)
such that the condenser (24) is locked to the base plate (12).
18. The method of claim 17, wherein the step of twisting each tab (52, 54) comprises bending
each tab (52, 54) about a bending axis (x-x).
19. The method of claim 18, wherein the step of twisting each tab (52, 54) comprises applying
a bending force (P), wherein the bending axis (x-x) lies on a plane (AA) having a
minimum amount of resistance towards the bending force (P).
20. The method of claim 17, wherein the step of twisting each tab (52, 54) comprises bending
each tab (52, 54) about a bending axis (x-x) that intersects a contact point (A) at
which the internal distal upper edge (66) contacts the base plate (12) and at which
the internal distal upper edge (66) of each tab (52, 54) is positioned on the same
horizontal plane (AA) as the undersurface (72) of the base plate (12).
21. The method of claim 17, wherein the internal distal upper edge (66) of each said tab
(52, 54) is oriented non-orthogonally relative to the base plate undersurface (72),
and the step of twisting exerts a camming action between the internal distal upper
surface (66) and the base plate undersurface (72) to draw the condenser (24) tightly
against an upper surface (16) of the base plate (12).
22. The method of claim 17, wherein the step of twisting each tab (52, 54) comprises machine
twisting each tab (52, 54).