Electric compressor and method for assembling same

Abstract

An electric compressor has an electric motor housed in a casing and that drives a compression part for compressing a refrigerant guided into the casing, and a connecting part accommodating container in which an external power line is guided from an exterior of the casing, and accommodating a connecting part for electrically connecting the external power line that supplies power to the electric motor and an internal power line guided from the electric motor. An insertion hole through which the internal power line is inserted is provided to the connecting part container; the connecting part container can be split with a splitting line for splitting the connecting part container and splitting the insertion hole; a first rubber ring for blocking off the insertion hole in a liquid-tight state is disposed inside the connecting part container; and the first rubber ring is sandwiched between split walls forming the insertion hole.

Claims

1. An electric compressor, comprising: an electric motor contained in a casing, and driving a compression part compressing a refrigerant guided into the casing; and a connecting part container having an external power line supplying electric power to the electric motor guided in from outside the casing, and containing a connecting part electrically connecting, within the casing, the external power line and an internal power line guided from the electric motor; the connecting part container being provided with an insertion hole, the internal power line being inserted through the insertion hole; the connecting part container being splittable at a splitting line splitting the connecting part container and splitting the insertion hole; a first rubber ring being disposed within the connecting part container and blocking off the insertion hole in a liquid-tight state; and the first rubber ring being held sandwiched between split walls forming the insertion hole, wherein one of an engaging protrusion and an engaging concavity is formed on an inner surface of the split walls forming the insertion hole, and one of an engagement concavity engaging with the engaging protrusion and an engagement protrusion engaging with the engaging concavity is provided on an outer surface of the first rubber ring facing the inner surface of the split walls.

2. The electric compressor according to claim 1, wherein the external power line has a terminal pin connected to the connecting part container, and the terminal pin is covered by a second rubber ring and made liquid-tight.

3. The electric compressor according to claim 2, wherein the connecting part container is held sandwiched by the second rubber ring and the electric motor.

4. The electric compressor of claim 3, further comprising: a resin case having a lid pressing a coil wound around an end part of the electric motor, wherein a split portion of the connecting part container is integrated with the lid.

5. A method for assembling the electric compressor described in claim 2, comprising the steps of: inserting the internal power line into the first rubber ring; fitting the split connecting part container so that the first rubber ring with the internal power line inserted therein is held sandwiched between the split walls; and connecting the terminal pin, affixed to the second rubber ring and to a glass terminal plate, to the connecting part container.

6. The electric compressor of claim 2, further comprising: a resin case having a lid pressing a coil wound around an end part of the electric motor, wherein a split portion of the connecting part container is integrated with the lid.

7. The electric compressor of claim 1, further comprising: a resin case having a lid pressing a coil wound around an end part of the electric motor, wherein a split portion of the connecting part container is integrated with the lid.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a vertical cross-sectional diagram depicting an electric compressor pertaining to an embodiment of the present invention.

(2) FIG. 2 is a vertical cross-sectional diagram depicting key components surrounding a terminal case of the embodiment.

(3) FIG. 3 is a plan view diagram depicting the terminal case of FIG. 2.

(4) FIG. 4 is a side view diagram depicting the terminal case of FIG. 3.

(5) FIG. 5 is a side view diagram depicting an upper terminal case from the terminal case of FIG. 3.

(6) FIG. 6 is a vertical cross-sectional diagram depicting an expanded view of an end of the upper terminal case of FIG. 5.

(7) FIG. 7 is a side view diagram depicting a lower terminal case from the terminal case of FIG. 3.

(8) FIG. 8 is a vertical cross-sectional diagram depicting an expanded view of an end of the lower terminal case of FIG. 7.

(9) FIG. 9 is a vertical cross-sectional diagram depicting a first rubber ring affixed to the terminal case of FIG. 2.

(10) FIG. 10 is a vertical cross-sectional diagram depicting a second rubber ring affixed to the terminal case of FIG. 2.

(11) FIG. 11 is a side view diagram depicting an electric motor and the terminal case of the electric compressor of FIG. 1.

(12) FIGS. 12A to 12D are vertical cross-sectional diagrams each depicting a variation of structure surrounding the second rubber ring of FIG. 2.

(13) FIGS. 13A to 13D are vertical cross-sectional diagrams each depicting a further variation of structure surrounding the second rubber ring of FIG. 2.

DESCRIPTION OF EMBODIMENTS

(14) An electric compressor pertaining to an embodiment of the present invention is described below, with reference to the accompanying drawings.

(15) As depicted in FIG. 1, an electric compressor 21 is used as a compressor in a vehicle air conditioning device, for example. The electric compressor 21 includes a casing 2, which contains a scroll compression part 13 and an electric motor 1 that drives this scroll compression part 13. Through the operation of the electric motor 1, a refrigerant guided into the casing 2 is compressed by the scroll compression part 13 and expelled to outside.

(16) The casing 2 is configured as a main body part having a substantially cylindrical shape that contains the scroll compression part 13 and the electric motor 1. At one end of the main body part (the left-hand side in FIG. 1), an opening of the casing 2 is shut tight by a bottom face of an inverter container part 43 (the right-hand side end in FIG. 1).

(17) The inverter container part 43 is shaped as a container containing the inverter, and is affixed to the main body part of the casing 2 by a second bolt 46.

(18) The casing 2 is sealed tight with respect to the refrigerant supplied thereto. Electric power is supplied to the electric motor 1 from the inverter (not depicted) in the inverter container part 43 via an external power line 4 inserted through an opening formed in the bottom face of the inverter container part 43 that is part of the casing 2. The external power line 4 is configured from a glass terminal plate 29, a terminal pin 27, an insulator 31, and on the like. Also, the glass terminal plate 29 and an end face of the inverter container part 43 are fixed in place by a first bolt 45. Thus, the external power line 4 is affixed to the inverter container part 43.

(19) A terminal case (also termed connecting part container) 5 is provided between the inverter container part 43 and the electric motor 1. The external power line 4 and an internal power line 3 guided in from the direction of the electric motor 1 are connected to each other within the terminal case 5. The terminal case 5 is fixed in place, being sandwiched between the bottom face of the inverter container part 43 and an end face of the electric motor 1 (specifically, a lid 17 pressing a coil 15 into place).

(20) As depicted in FIG. 2 and FIG. 3, the terminal case 5 contains three connecting parts 6 for connecting three electric power lines in parallel. The terminal case 5 has terminal case parts 51, 52, 53 each containing one of the connecting parts 6 and being substantially identical to each other in shape. The terminal case 5 is shaped as an integrated whole of the terminal case parts 51, 52, 53 aligned in parallel while being offset by a predetermined distance with respect to a longitudinal direction (the left-right direction in FIG. 3). The present embodiment describes a terminal case in which three electric power lines are connected. However, no particular limitation to the invention is intended thereby. A single electric power line, two electric power lines, or four or more electric power lines may also be provided.

(21) As depicted in FIG. 2, the terminal case 5 contains a connecting part 6 electrically connecting the external power line 4 and the internal power line 3 within the casing 2.

(22) The internal power line 3 is guided from the electric motor 1 and inserted into an insertion hole 9 provided in the terminal case 5.

(23) As depicted in FIG. 4, the terminal case 5 is split horizontally into an upper terminal case 5a and a lower terminal case 5b at a splitting line 7. The splitting line 7 is provided so as to further split the insertion hole 9 horizontally.

(24) Also, as depicted in FIG. 4 and FIG. 5, the upper terminal case 5a has tab parts 37b that are each fittable into respective tab-fitting parts 37a (see FIG. 7) of the lower terminal case 5b. The tab parts 37b are provided with separation therebetween.

(25) As depicted in FIG. 3, a top face of the upper terminal case 5a is provided with a terminal pin connection hole 23 at a position distant from the insertion hole 9 for connecting the terminal pin 27, which is a part of the external power line 4. As depicted in FIG. 2, a tip of the terminal pin 27 is inserted along a direction perpendicular to the splitting line 7 as far as the central vicinity of the terminal case 5. Also, another tip of the terminal pin 27 is connected to the inverter (not depicted) positioned outside the casing 2.

(26) As depicted in FIG. 2, a first rubber ring 11a is held sandwiched between walls 8 of the terminal case 5, split by the formation of the insertion hole 9.

(27) As depicted in FIG. 9, the first rubber ring 11a has an engagement concavity 33a corresponding to an engaging protrusion 35a (see FIG. 6 and FIG. 8) of the walls 8 forming the insertion hole 9 in the terminal case 5. The engagement concavity 33a is positioned substantially centrally along the side walls of the first rubber ring 11a having the engagement concavity 33a.

(28) Also, the side walls of the first rubber ring 11a that do not have the engagement concavity 33a instead have a through-hole 39, shaped as a hollow having a diameter substantially equal to the diameter of the internal power line 3.

(29) The above-described protrusion and concavity of the engaging protrusion 35a on the walls 8 forming the insertion hole 9 and the engagement concavity 33a corresponding thereto may be reversed. That is, an engaging concavity and an engagement protrusion may be provided.

(30) The glass terminal plate 29 is a plate-shaped member made of glass, connected to the terminal pin 27 so as to perpendicularly intersect the axis of the terminal pin 27. The insulator 31, which is, for example, tubular and made of ceramic, is provided on the surface of the glass terminal plate 29 on a side thereof where the terminal case 5 is positioned. The insulator 31 is provided as a pair for each one of the terminal pin 27, the pair being positioned with separation and with the terminal pin 27 therebetween.

(31) As depicted in FIG. 10, a second rubber ring 11b covers a portion of the terminal pin 27 between the glass terminal plate 29 and the terminal case 5 that is in contact with the refrigerant within the casing 2. The length of the portion covered by the second rubber ring 11b, that is, the distance between the glass terminal plate 29 and the terminal case 5, is on the order of twice the vertical dimension of the insulator 31 (depicted as the vertical direction in FIG. 2).

(32) Also, in FIG. 2, the second rubber ring 11b is step-shaped with a portion having a smaller diameter (on the order of ⅕th smaller in terms of the vertical dimension depicted). The insulator 31 is positioned in the space outside this smaller-diameter portion.

(33) A plurality of protrusions and concavities may be provided on an inner circumferential face (the portion in contact with the terminal pin 27) and bottom face (the portion in contact with the terminal case 5) of the second rubber ring 11b, which serve to improve the seal properties thereof through labyrinth seal effects.

(34) As depicted in FIG. 11, an iron core 41 making up the electric motor 1 is sandwiched (above and below as depicted) by a bobbin 19 made of resin. A coil 15 is wound around the bobbin 19.

(35) A lid 17 pressing the coil 15 into place is arranged on the side of the bobbin 19 positioned next to the terminal case 5 (the top side as depicted in FIG. 11). The lid 17 is integrated with the lower terminal case 5b.

(36) In FIG. 11, the length of the lid 17 along the direction perpendicular to a motor axis L (the horizontal direction as depicted) is approximately equal to the size of the bobbin 19 and covers a portion where the coil 15 is wound.

(37) A method for assembling the above-described terminal case 5 is described next.

(38) First, the internal power line 3 is inserted into the through-hole 39 of the first rubber ring 11a (internal power line insertion).

(39) Next, the tab-fitting part 37a provided on the lower terminal case 5b is fit onto the tab part 37b provided on the upper terminal case 5a so as to sandwich the inserted first rubber ring 11a between the walls 8 split when forming the insertion hole 9 (terminal case fitting).

(40) Then, the terminal pin 27 to which the second rubber ring 11b and the glass terminal plate 29 are attached is connected to the terminal pin connection hole 23 provided on the terminal case 5 (terminal connection).

(41) According to the configuration as described above, the present embodiment has the following action and effects.

(42) The splitting line 7 splitting the insertion hole 9 not only splits the terminal case 5 but also causes the first rubber ring 11a to be held sandwiched between the walls 8 split by forming the insertion hole 9 so that the interior of the container is liquid tight. Affixing the second rubber ring 11b so as to cover the portion of the terminal pin 27 that is in contact with the refrigerant within the casing enables prevention of contact between the refrigerant and the terminal pin 27, and enables terminal part insulation to be achieved with a simple configuration.

(43) Also, the glass terminal plate 29, which is a part of the external power line 4, and the end face of the inverter container part 43 are fixed in place by the first bolt 45, such that there is no leakage of liquid refrigerant from the direction of the inverter container part 43.

(44) The terminal case 5 is shut tight by the first rubber ring 11a, thus enabling a configuration in which the first rubber ring 11a is unlikely to fall due to pressure differences between the inside and the outside of the terminal case 5.

(45) Furthermore, the engagement concavity 33a corresponding to the engaging protrusion 35a formed on the walls 8 forming the insertion hole 9 is provided on the first rubber ring 11a. Thus, the first rubber ring 11a is prevented from falling from the terminal case 5.

(46) The tab-fitting part 37a provided on the lower terminal case 5b fits onto the tab part 37b provided on the upper terminal case 5a, and in addition, the terminal case 5 is sandwiched between the second rubber ring 11b and the electric motor 1. Thus, the upper terminal case 5a and the lower terminal case 5b are prevented from separating.

(47) Also, the terminal case 5 is sandwiched by having one end face against the end face of the inverter container part 43 and the second rubber ring 11b, and the other end face against the lid 17 pressing the coil 15 into place. Thus, the second rubber ring 11b is able to act as a buffer when power is applied from outside.

(48) When a vibration or the like is applied to the bobbin 19 on which the coil 15 is wound, a coil insulation defect occurs as the coil 15 ravels. Thus, the lid 17 presses the coil 15 in order to prevent unraveling of the coil 15. However, given that the lower terminal case 5b and the lid 17 pressing the coil 15 into place are integrated as one, the electric compressor is achieved with a simple assembly and without losing the objective of pressing the coil 15.

(49) The assembly method, which includes inserting the internal power line 3 into the first rubber ring 11a and fitting the split terminal case 5 so that the inserted first rubber ring 11a is held sandwiched between the walls 8 split by forming the insertion hole 9, easily enables the interior of the terminal case 5 to be made liquid-tight. Accordingly, the terminal case 5 has insulation properties without requiring that the entire terminal part be covered by resin or rubber. This enables the terminal part to be insulated easily by assembly and attachment.

(50) The above-described embodiment describes an example applied to a scroll compressor used in a vehicle air conditioning device. However, a typical air conditioner may also be used, as may a multilevel compressor combining a rotary compressor and some other type of compressor.

(51) The following variations may also be applied to the structure surrounding the second rubber ring 11b depicted in FIG. 2.

(52) FIGS. 12A to 12D and FIGS. 13A to 13D depict examples of the variations on the structure surrounding the second rubber ring 11b depicted in FIG. 2.

(53) As depicted in FIG. 12A, a fitting protrusion may be provided on both ends of the second rubber ring 11b, and a fitting concavity fitting correspondingly with the fitting protrusion may be provided respectively on the casing side and the connecting part container side.

(54) These fitting parts serve to make the horizontal cross section smaller than the central axle. Accordingly, this enables prevention of breakage in the connecting part container and the glass terminal due to excessive load, without loss of insulation. Also, the fitting is performed by the protrusions and concavities provided between the second rubber ring 11b, the casing side, and the connecting part container side. These protrusions and concavities thus create a seal effect, such that the second rubber ring need not necessarily be actively sandwiched and impose a large load.

(55) Then, the natural length of the fitting protrusion on the second rubber ring 11b with respect to the axis direction is beneficially longer than the length of the corresponding fitting concavity provided on the casing side and/or on the connecting part container side with respect to the axis direction. Accordingly, the fitting protrusion on the second rubber ring touches the corresponding component first. This enables difficult-to-measure units of tolerance and the like to be absorbed in the narrow portion of the second rubber ring where the horizontal cross-section is smaller.

(56) Also, as depicted in FIG. 12B, the axial length of the fitting protrusion on the casing side (the top side as depicted) may be longer than in FIG. 12A (e.g., one of the fitting protrusions may be longer than the other fitting protrusion). A low-rigidity component may thus crush the rubber and have the load thereon reduced through elastic forces.

(57) Also, as depicted in FIG. 12C, an end part of the second rubber ring 11b on the connecting part container side (the bottom side as depicted) may serve as the fitting concavity, while the other end part, on the casing side, serves as the fitting protrusion. Further, as depicted in FIG. 12D, the second rubber ring 11b may be configured with the fitting concavity provided on both ends.

(58) Also, as depicted in FIG. 13A, the axial length of the fitting concavity on the casing side (the top side as depicted) may be longer than in FIG. 12D (e.g., one of the fitting concavities may be longer than the other fitting concavity). A low-rigidity component may thus crush the rubber and have the load thereon reduced through elastic forces.

(59) Also, as depicted in FIG. 13B, the fitting protrusion may be provided on one end part of the second rubber ring 11b (the casing side as depicted), and the other end part may be shaped to have substantially the same diameter as the center of the second rubber ring 11b. In the depicted variation, the horizontal cross-section is smaller than other parts and thus has weaker rigidity, but crushes the rubber of the fitting protrusion and experiences a reduced load due to elastic force.

(60) As depicted in FIG. 13D, a hermetic seal 12 may be used during assembly on the casing side in order to preserve insulation.

(61) Also, as depicted in FIG. 13C, the central part of the second rubber ring 11b may be made narrower than both end parts. In FIG. 13C, the protrusion and concavity structure is not used for fitting. The central part, which has a smaller horizontal cross-section and thus weaker rigidity, crushes the rubber. Accordingly, elastic forces enable the load to be reduced in comparison to cases where a substantially equal diameter is maintained throughout.

REFERENCE SIGNS LIST

(62) 1 Electric motor 2 Casing 3 Internal power line 4 External power line 5 Terminal case (connecting part container) 5a Upper terminal case 5b Lower terminal case 6 Connecting part 7 Splitting line 8 Walls 9 Insertion hole 11a First rubber ring 11b Second rubber ring 13 Scroll compression part 15 Coil 17 Lid 19 Resin case (Bobbin) 21 Electric compressor 23 Terminal pin connection hole 27 Terminal pin 29 Glass terminal plate 31 Insulator 32 Glass 33a Engagement concavity 35a Engaging protrusion 37a Tab-fitting part 37b Tab part 39 Through-hole 41 Iron core 43 Inverter container part 45 First bolt 46 Second bolt 51, 52, 53 Terminal case parts L Motor axis