Patent Application
20140335721
The present invention relates to connection terminals used for aluminum electric wires, connection devices including the connection terminals, methods for manufacturing the connection devices, motors using the connection devices, and compressors using the motors and blowers using the motors.
Conventionally, electrical apparatus such as transformers, reactors, and magnetrons have employed insulated electric wires made of aluminum as their core wires, in order to reduce weight of the electrical apparatus. Hereinafter, an insulated electric wire in which its core wire is made of aluminum and the outer peripheral surface of the core wire is coated with an insulating coating, is referred to as an aluminum electric wire. Aluminum has characteristics that it tends to suffer a deformation due to a creep phenomenon. Hereinafter, the deformation due to the creep phenomenon is referred to as the creep deformation. In the aluminum electric wire, its stress is relaxed when the creep deformation progresses. Hereinafter, such the relaxation of the stress caused by the creep deformation is referred to as the stress relaxation.
Concerning connections of aluminum electric wires, there have been proposals to address the creep deformation of aluminum, as shown in Patent Literatures 1 and 2.
In Patent Literature 1, a configuration is proposed in which a crimp terminal has a groove formed in a crimping part thereof, with the crimp terminal being connected to the aluminum electric wire. In Patent Literature 1, the formation of the groove is expected to address the creep deformation. Note that the crimp terminal referred in Patent Literature 1 corresponds to the connection terminal according to the present application.
In Patent Literature 2, the proposed connection terminal is such that a plurality of strain regions is formed in a plate-like part included in the connection terminal. The plate-like part is formed by folding a crimping part included in the connection terminal. In Patent Literature 2, the formation of the plurality of the strain regions is expected to address the creep deformation.
A connection terminal according to the present invention is used for an aluminum electric wire which includes a core wire and an insulating coating which covers the outer peripheral surface of the core wire. The connection terminal includes a tab part and not smaller than four pinching plates which hold the aluminum electric wire.
The pinching plates each include a first slit and contact surfaces. In the first slit, a first open end is located in one side of the slit while a first tip is located in the other side. Moreover, the aluminum electric wire is press-fitted into the first slit. The contact surfaces are in contact with the aluminum electric wire that is press-fitted into the first slit. The contact area, in which the contact surfaces are in contact with the core wire, is an area of 100% to 200% of the radial cross-sectional area of the core wire.
Moreover, a connection device according to the present invention is used for an aluminum electric wire that includes a core wire and an insulating coating that covers the outer peripheral surface of the core wire. The connection device includes a connection terminal and a holding part.
The connection terminal includes a tab part and not smaller than four of pinching plates which hold the aluminum electric wire. The holding part includes cavities into which the connection terminals are inserted.
The pinching plates each include a first slit and contact surfaces. In the first slit, a first open end is located in one side of the slit, while a first tip is located in the other side. Moreover, the aluminum electric wire is press-fitted into the first slit. The contact surfaces are in contact with the aluminum electric wire that is press-fitted into the first slit. The contact area, in which the contact surfaces are in contact with the core wire, is an area of 100% to 200% of the radial cross-sectional area of the core wire.
The cavity includes a wall surface and a second slit. The wall surface surrounds at least the pinching plates of the inserted connection terminal. The second slit is formed such that, in the wall surface, a second open end is located in one side of the slit while a second tip is located in the other side, at a location facing the first slit. In the second slit, the second open end is larger in a slit width than the second tip.
The present invention is intended to suppress progress of a creep deformation in electrical apparatus that employs an aluminum electric wire, through the use of a connection terminal and a connection device including the connection terminal according to each of embodiments of the invention to be described later.
Moreover, the connection terminal according to the embodiment of the invention and the connection device including the connection terminal, can suppress a loss of stress on the connection terminal to hold the aluminum electric wire, with the loss resulting from the creep deformation.
Accordingly, the stress with which the connection terminal holds the aluminum electric wire is securely maintained.
As a result, the use of the connection device according to the embodiment of the present invention allows a highly reliable motor. The motor can be used in a compressor and a blower.
This means that conventional connection terminals involve the following subjects to be improved.
That is, according to Patent Literature 1, a specialized jig is needed for crimping a crimp terminal. In addition, in Patent Literature 1, an insulating cap is needed to cover a crimping part for securely maintaining the part's insulation to other conductive bodies.
Moreover, the crimp terminal described in Patent Literature 1 requires that the connected crimping part is fixed to be immobilized against vibrations. For example, in the case of a motor, the crimping part is fixed to such as a coil end part of a winding formed of the aluminum electric wire. The need for such the process leads to low productivity.
These reasons require additional manufacturing facilities, component counts, and working man-hours, in accordance with Patent Literature 1. In addition, these reasons become factors responsible for increased costs as well.
The connection terminal is also used in a motor for driving such as a compressor and a blower. The motor for driving the compressor is used in environments with strong vibrations and wildly-varying temperatures. When the motor, such as one used in the compressor, is used under particularly difficult conditions in terms of vibration and temperature variation, the creep deformation of the aluminum electric wire becomes easier to progress. This is because, when the fixation is made insufficiently between the connection terminal and a fixing member for fixing the connection terminal, the connection terminal will move relative to the fixing member. Accumulation of small movements is considered to help the creep deformation progress. The progress of the creep deformation causes a loss of stress on the connection terminal relative to the aluminum electric wire.
Under such the difficult conditions, when using the connection terminal described in Patent Literature 2, the creep deformation progresses to cause a stress relaxation. The occurrence of the stress relaxation between the aluminum electric wire and the connection terminal, results in a decrease in joint strength between the aluminum electric wire and the connection terminal. The decrease in the joint strength, in turn, increases contact resistance of the joining portion between the aluminum electric wire and the connection terminal. The increase in the contact resistance is thought to cause an unexpected malfunction such as a halt of operation of the electrical apparatus which uses the connection terminal. Consequently, reliability is low in the electrical apparatus in accordance with Patent Literature 2.
Accordingly, in the case where the aluminum electric wire is used in the motor for use in the compressor, blower, etc., a highly reliable connecting method which provides a connection capable of withstanding harsh service environments is desired for the connecting portion of the aluminum electric wire.
Hereinafter, descriptions will be made regarding a connection terminal exhibiting particularly outstanding advantages when used with an aluminum electric wire, and regarding a connection device including the connection terminal, with reference to the accompanying drawings.
In addition, a method for manufacturing the connection device will be described with reference to the drawings.
Moreover, descriptions will also be made regarding a motor using the connection device, a compressor using the motor, and a blower using the motor, with reference to the drawings.
Note, however, that each of the embodiments described hereinafter is one example of applications of the present invention, and does not set any limit to the technical scope of the present invention.
A connection terminal according to a first embodiment of the present invention will be described with reference to
The connection terminal according to the first embodiment of the invention is used for the aluminum electric wire that includes the core wire and an insulating coating which covers the outer peripheral surface of the core wire.
As shown in
Each of pinching plates 12 includes first slit 13 and contact surfaces 14. First slit 13 has first open end 15 located in one side of the slit and first tip 16 located in the other side.
As shown in
As shown in
Further details of this are as follows.
As shown in
Connection terminal 10 includes tab part 11. Into tab part 11, a corresponding flat connection terminal is fitted, as shown in a second embodiment and subsequent ones to be described later.
As shown in
That is, the stresses are applied to core wire 17A from the four directions. Against these stresses, aluminum electric wire 17 generates reaction forces. The progress of the creep deformation can be suppressed when the stresses applied from contact surfaces 14 to aluminum electric wire 17 are moderately balanced with the reaction forces generated from aluminum electric wire 17 to contact surfaces 14. Hereinafter, the stresses applied to core wire 17A from the four directions are referred to as the internal stresses.
As shown in
On the other hand, when the contact area is larger than 200%, the strength of the aluminum electric wire decreases. That is, when the aluminum electric wire is press-fitted into the first slit, the core wire is deformed by the contact surfaces. As a result of the deformation of the core wire, the radial cross-sectional area of the core wire becomes small. The decrease in the radial cross-sectional area of the core wire decreases the wire strength of the aluminum electric wire. An excessive decrease in the wire strength of the aluminum electric wire sometimes results in a broken wire. This region is referred to as wire-strength decreasing region 25.
As can be seen from the above description, in accordance with the connection terminal according to the first embodiment of the present invention, the stresses are applied to the core wire from the contact surfaces in the four directions at the contact points where the core wire is in contact with the contact surfaces. Against the stresses, the reaction forces are generated from the core wire to the contact surfaces. When the stresses and the reaction forces are moderately in valance, the progress of the creep deformation can be suppressed even under difficult conditions. This allows the internal stresses to be maintained.
When the contact area is in the range from 100% to 200% of the radial cross-sectional area of the core wire, it is possible to maintain the state where the stresses and the reaction forces are moderately in valance. Therefore, the progress of the creep deformation can be suppressed, which thereby maintains the wire strength of the press-fitted aluminum electric wire.
Note, however, that the number of the pinching plates may be not smaller than four.
For example, as shown in
Next, configurations to obtain the contact area ranging 100% to 200% will be described.
In addition to the shape described above, the connection terminal according to the first embodiment of the invention is such that each of the contact surfaces has an angle of inclination ranging 15° to 75° relative to the direction in which the not smaller than four pinching plates are arranged.
Further details of this are as follows.
As shown in
Each of contact surfaces 14 has an inclination angle α ranging 15° to 75° relative to direction 23 in which the pinching plates are arranged.
Table 1 shows the degree of variations in contact resistance which occurs between the aluminum electric wire and the contact surfaces, before and after a thermal shock test.
The thermal shock test was carried out with the following conditions. The ambient temperature was varied from −40° C. to 120° C. One cycle consisted of states, i.e. the state where the ambient temperature of −40° C. was kept for 30 minutes and the state where the ambient temperature of 120° C. was kept for 30 minutes. The cycle was repeated 1000 times, i.e. 1000 cycles. Incidentally, these conditions are for an accelerated test to determine whether or not a compressor, shown in a fourth embodiment to be described later, can withstand practical use.
Before and after the thermal shock test, when the variations in the contact resistance were observed within 1 mΩ, the contact resistance is determined to be in “absence of variations.” On the other hand, when the variations in the contact resistance observed exceeds 1 mΩ, the contact resistance is determined to be in “presence of variations.”
As shown in Table 1, when inclination angle α is smaller than 15°, the result after the thermal shock test has shown that the contact resistance exhibits the variations. The reason of this is considered that the internal stresses cannot be maintained in the radial direction of the aluminum electric wire. That is, in the aluminum electric wire, the stress relaxation occurs due to the progress of the creep deformation. The occurrence of the stress relaxation increases the contact resistance between the aluminum electric wire and the connection terminal. The contact resistance increases to exceed the allowable value, resulting in the poor electrical connection.
On the other hand, when inclination angle α is larger than 75°, it is considered that the internal stresses cannot be maintained in the radial direction of the aluminum electric wire in the early stage of the thermal shock test. That is, in the aluminum electric wire, the stress relaxation occurs due to the progress of the creep deformation. The occurrence of the stress relaxation increases the contact resistance between the aluminum electric wire and the connection terminal. The contact resistance increases to exceed the allowable value, resulting in the poor electrical connection.
Note, however, that similar functional advantages can be expected even when pinching plates 12 have other cross-sectional shapes in direction 23 in which the plates are arranged, including a curved shape as shown in
Next, a case of the embodiment in which a plurality of the aluminum electric wires is press-fitted into the connection terminal will be described.
Using
In addition to the shape described above, the connection terminal according to the first embodiment is such that the first slit has a temporarily holding part where the aluminum electric wire is temporarily held when the aluminum electric wire is press-fitted.
Further details of this are as follows.
As shown in
Concerning the connection terminal having such the temporarily holding part, its functional advantages will be described through explanations of a comparative example and a specific example.
For example, two of the aluminum electric wires are press-fitted into a first slit included in a connection terminal. For the connection terminal without the temporarily holding part, the first slit becomes in the state of being opened, at the stage of the first one of the aluminum electric wires having been press-fitted. In the state of the first slit being opened, when the second one of the aluminum electric wires is press-fitted, the aluminum electric wire is sometimes in insufficient contact with the contact surfaces. As a result, the insulating coating that covers the core wire is not sufficiently removed. The insufficient removal of the insulating coating of the aluminum electric wire increases the contact resistance between the core wire and the contact surfaces. The contact resistance increases to exceed the allowable value, resulting in a poor electrical connection.
By contrast, as shown in
After that, as shown in
As shown in
As a result, core wires 17A of two aluminum electric wires 17 and 117 can be in contact with contact surfaces 14 in the range corresponding to the appropriate contact resistance.
A connection device according to a second embodiment of the present invention will be described, with reference to
Note, however, that the direction in which the connection device is inserted into the cavity is not limited to that in the following descriptions.
The connection device according to the second embodiment of the invention is used for an aluminum electric wire which includes a core wire and an insulating coating that covers the outer peripheral surface of the core wire.
As shown in
For connection terminals 10, the descriptions thereof in the first embodiment are cited herein. Note that, needless to say, connection terminals 10 can be replaced by connection terminals 10A in the following descriptions.
As shown in
Further details of this are as follows.
The holding part can be formed with a resin. The resin may be polybutylene terephthalate (referred to as PBT, hereinafter), a liquid crystal polymer (referred to as an LCP, hereinafter), or the like.
In particular, the PBT resin is advantageous in view of heat resistance and electric characteristics. The PBT resin is less expensive than the LCP. A specific example of the PBT resin is a PBT resin 1101G-30 manufactured by Toray Industries, Inc.
As shown in
As shown in
As long as second slit 34 included in wall surface 33 has the taper shape, the aluminum electric wire to be connected is held by any part of second slit 34 depending on the wire diameter. Accordingly, the use of the connection device including cavities 31 with one type of the shape allows connections of other electric wires than the aluminum electric wire. That is, this provides commonality of the connection devices.
The cavity according to the second embodiment includes an electric wire mount in the inside of the space surrounded by the wall surface. As shown in
In the cavity with the configuration described above, the aluminum electric wire is disposed. As shown in
Note that, in
As shown in
As a result, aluminum electric wire 17 and connection terminal 10 are connected with each other with a stable contact resistance. Aluminum electric wire 17 and connection terminal 10 are connected with each other with high reliability. Mounting work of aluminum electric wire 17 can be performed in a state in which the wire is held by second slit 34. This improves workability of the mounting.
Next, configurations featuring more outstanding advantages will be described.
In the connection device according to the second embodiment of the invention, each of the pinching plates includes a fitting part while the cavity includes a to-be-fitted part. The pinching plate includes the fitting part in the direction orthogonal to the direction in which the first slit opens from the first tip toward the first open end. The cavity includes the to-be-fitted part that fits onto the fitting part.
The specific configuration is as follows. The fitting part is a projection which protrudes from a side surface of the pinching plate toward the outside. The to-be-fitted part is a recess, which fits onto the projection, in the inner wall surface of the cavity.
Moreover, detailed descriptions will be made using
As shown in
As shown in
Descriptions will be made regarding functional advantages of the connection device with the configuration described above.
Vibrations and temperature variations are applied to the connection device to which the aluminum electric wire and the connection terminal are connected. If there is some degree of freedom in the insertion position of the connection terminal in the cavity, the connection terminal can move relative to the cavity due to influences of the applied vibrations and temperature variations. Its moving distances are small; however, the influences thereof are accumulated when the connection terminal is subjected to strong vibrations and temperature variations over a long period of time. The accumulation of the small movements will accelerate the creep deformation of the aluminum electric wire. The accelerated creep deformation causes stress relaxation of the aluminum electric wire. As a result, the contact resistance increases between the aluminum electric wire and the connection terminal. Alternatively, a decrease in wire strength of the aluminum electric wire causes the aluminum electric wire to be broken.
Hence, connection device 30A according to the second embodiment is used as shown in
As a result, it is possible to prevent connection terminal 10 from moving relative to cavity 31 even when the vibrations and temperature variations are applied to connection device 30A.
Incidentally, the direction in which connection terminal 10 moves relative to cavity 31 includes rotational directions, a fore-and-aft direction, and a side-to-side linear direction depending on the mode of usage of connection device 30A.
As shown in a fourth embodiment to be described later, in the case where the connection device according to the second embodiment is used in a compressor, it is possible to prevent the movement in the rotational directions.
Note, however, that both the fitting parts included in the pinching plates and the to-be-fitted parts included in the cavity may employ other respective shapes, as long as the connection device can be prevented from moving relative to the cavity.
For example, as shown in
Alternatively, as shown in
Moreover, it does not matter what the numbers of the fitting parts and the to-be-fitted parts are as long as they can prevent the connection terminal from moving relative to the cavity. For example, only three of the fitting parts may be disposed for the outer pinching plates. Alternatively, only two of the fitting parts may be diagonally disposed for the outer pinching plates.
As can be seen from the above descriptions, the use of the connection terminal according to the second embodiment allows the suppression of the creep deformation of the aluminum electric wire that is used under the difficult conditions in terms of vibration and temperature variation. The suppression of the creep deformation allows the prevention of the occurrence of the stress relaxation. As a result, it is possible to provide the connection device in which the aluminum electric wire and the connection terminal are connected to each other with high reliability.
A method for manufacturing the connection devices shown in the second embodiment of the present invention will be described using
The method for manufacturing the connection device according to the third embodiment of the invention includes a process of inserting the connection terminal into a cavity. In the inserting process, the insertion speed of the connection terminal into the cavity is 40 mm/sec to 200 mm/sec.
Moreover, in the inserting process, an insertion angle is within ±10°. The insertion angle is formed by the center line of the connection terminal along an insertion direction of the connection terminal which is inserted into the cavity and the center line of the cavity along an insertion direction of the cavity into which the connection terminal is inserted.
Furthermore, the method includes a process of bending the tab part relative to the pinching plates in the connection terminal. Then, after the bending process, an inserting process is performed.
Details of this are as follows.
As shown in
As shown in
After that, as indicated by the arrow in
At that time, the insertion speed at which connection terminal 10 is inserted into cavity 31 is set to be 40 mm/sec to 200 mm/sec. By setting the insertion speed to be 40 mm/sec to 200 mm/sec, loads on aluminum electric wire 17 being press-fitted into first slits 13 can be reduced.
That is, when inserting connection terminal 10 into cavity 31, the insulating coating applied to connection terminal 10 is removed by contact surfaces 14 included in pinching plates 12. Moreover, aluminum electric wire 17 is press-fitted into first slits 13 such that the core wire comes in contact with contact surfaces 14 to exhibit a predetermined contact resistance. Accordingly, when inserting connection terminal 10 into cavity 31, these factors need to be taken into consideration in inserting connection terminal 10.
The result of a verification test of this is shown in Table 2.
The verification test has shown that the insertion speeds slower than 40 mm/sec result in broken aluminum electric wires 17. This appears to be because so-called moving-together phenomenon occurs in which aluminum electric wire 17 moves together with connection terminal 10 that is inserted into cavities 31.
Moreover, the insertion speeds faster than 200 mm/sec result in failures of twisted connection terminals 10 or broken cavities 31.
As can be seen from the above result, with the insertion speed ranging 40 mm/sec to 200 mm/sec, it is possible to suppress the occurrence of the failures in the manufacturing process in which connection terminal 10 is inserted into cavity 31.
Moreover, as shown in
It is considered that the deformation of connection terminal 10 depending on the insertion angle is considered to be factors responsible for a state of twisting between cavity 31 and connection terminal 10. The state of twisting is considered to accelerate the creep deformation when the connection device is used under difficult conditions.
Consequently, the restriction of the insertion angle allows the suppression of the occurrence of the creep deformation in the aluminum electric wire.
Therefore, as shown in the fourth embodiment to be described later, the connection device into which the connection terminals are press-fitted is used in a compressor. It is possible to suppress the acceleration of the creep deformation even when the connection device described above is used inside the compressor under difficult conditions in terms of vibration and temperature variation. The suppression of the acceleration of the creep deformation allows the prevention of the stress relaxation of the aluminum electric wire. As a result, it is possible to provide the connection device in which the aluminum electric wire and the connection terminal are connected to each other with high reliability.
Alternatively, as shown in
As shown in
For example, there are sometimes cases where the connection device is subjected to a height limit when used in such as the compressor shown in the fourth embodiment.
In the cases, the flat connection terminal to be fitted into the connection terminal is sometimes formed to be a flag-shaped terminal. Moreover, when subjected to the height limit, there is no choice but to bend the connection terminal at a boundary between the tab part and the pinching plates thereof. Therefore, as shown in
Consequently, it is possible to suppress poor contact due to the deformation of the connection terminal. As a result, there is no occurrence of heat generation or the like caused by the poor contact at the connecting portions between the connection terminal and the aluminum electric wire, the connection terminal and the flat connection terminal, the connection terminal and the flag-shaped terminal, and the like.
Table 3 shows a relation between contact resistance and the bending of the connection terminal.
“No-bending” referred in Table 3 is the states of connection terminals 10 and 10A shown in the first and second embodiments, respectively.
“Pre-bending” is the state of connection terminal 10D that is formed in advance by bending process S5 described in the third embodiment. “Post-bending” is the state of connection terminal 10E shown in
As can be seen from
This is thought to be due to an unnecessary deformation of connection terminal 10E, which is caused by bending tab part 11 without direct holding of the pinching plates 12 side when bending connection terminal 10E.
Moreover, variations in contact resistance of the flag-shaped terminal have been verified, with the terminal being subjected to insertion-removal cycles, i.e. repeatedly inserting and removing the terminal into and from tab part 11.
The result is shown in
In other words, the pre-bending of the connection terminal yields a stable shape of the connection terminal. It is the pre-bended connection terminal that is inserted into the cavity. Therefore, the portion connected to the pre-bended connection terminal will provide the stable contact resistance. As a result, it is possible to provide the connection device in which the aluminum electric wire and the connection terminal are connected to each other with high reliability.
Note, however, that the direction in which the tab part is bent relative to the connection terminal is optionally set in accordance with situations of such as the flag-shaped terminal to be fitted. The direction in which the tab part is bent relative to the connection terminal is not limited to that in the above descriptions.
A fourth embodiment of the present invention will be described, with reference to the accompanying drawings.
The motor using the connection device shown in the second embodiment of the invention will be described using
Motor 70 includes rotary shaft 71, a pair of shaft bearings 72, rotor 73, and stator 74.
The pair of shaft bearings 72 are attached to rotary shaft 71 so as to sandwich rotor 73. Rotor 73 includes magnets 75 at the outer periphery thereof. Rotor 73 is inserted into the inside of stator 74 such that the stator 74 faces magnets 75 included at the outer periphery of the rotor.
As shown in
In this way, the motor according to the fourth embodiment of the present invention is configured.
Note that, as shown in
The motor described above is used in a compressor shown in
In addition, the compressor using the motor will be described using
Compressor 80 includes motor 70 and compression part 82 in case 81 thereof. Case 81 is equipped with an intake pipe and a discharge pipe.
A coolant suctioned into case 81 via the intake pipe is conveyed into compression part 82. Compression part 82 is driven by motor 70. Compression part 82 is driven to compress the coolant. The compressed coolant is discharged from the discharge pipe into a refrigeration cycle.
Like this, the motor is used in the blower shown in
Blower 90 includes motor 70 in case 91 thereof. A fan is attached to rotary shaft 71. The rotation of rotor 73 causes a rotation of the fan attached to rotary shaft 71.
The motor according to the fourth embodiment of the invention is applicable to a wide range of applications. Among the applications, the compressor is used under difficult conditions in terms of vibration and temperature variation and the blower is used under difficult conditions in terms of vibration.
However, as described in detail in the second embodiment, the use of the connection device according to the second embodiment of the invention allows the suppression of the movement of the connection terminal relative to the cavity even when being used under the difficult conditions in terms of vibration and temperature variation.
Accordingly, the creep deformation occurring in the aluminum electric wire is suppressed. The suppression of the creep deformation, in turn, allows the prevention of the stress relaxation. As a result, it is possible to provide the motor in which the aluminum electric wire and the connection terminal are connected to each other with high reliability. Moreover, it is possible to provide the compressor using the motor and the blower using the motor.
Advantages of the compressor and the blower according to the fourth embodiment of the invention were examined, in comparison with comparative ones using conventional connection terminals. The result will be described using Table 4,
The comparison was made through a thermal shock test and a vibration test. Table 4 shows combinations of the test objects. After each of the tests had been conducted, variations in contact resistance were examined and evaluated.
Using
The thermal shock test was carried out with the following conditions. The ambient temperature was varied from −40° C. to 120° C. One cycle consisted of states, i.e. the state where the ambient temperature of −40° C. was kept for 30 minutes and the state where the ambient temperature of 120° C. was kept for 30 minutes. The cycle was repeated 2000 times, i.e. 2000 cycles.
The vibration test was carried out with the following conditions. The vibration frequency was in a range from 10 Hz to 55 Hz. The linear sweep time was one minute. The amplitude was 1.6 mm, with a current of 0.1 A flowing through the test objects. The vibration was made in three directions, i.e. fore-and-aft, up-and-down, and side-to-side directions.
From Table 4 and
On the other hand, the thermal shock test allows to confirm that Example 1 exhibits the contact resistance comparable to or smaller than that of the combination of the conventional connection terminal and the copper electric wire (Comparative Example 2).
Moreover, from Table 4 and
On the other hand, the vibration test has shown that Example 1 exhibits the contact resistance comparable to or smaller than that of the combination of the conventional connection terminal and the copper electric wire (Comparative Example 2).
As can be seen from the above results, the use of each of the embodiments of the present invention allows the following functional advantages.
That is, the aluminum electric wire can be used, which allows a reduction in weight of electrical apparatus.
Further, it is possible to prevent the occurrence of the stress relaxation by suppressing the creep deformation, even in the use of the aluminum electric wire under difficult conditions in terms of vibration and temperature variation. The occurrence of the stress relaxation has been a matter of concern for the aluminum electric wire. That is, in accordance with each of the embodiments of the present invention, it is possible to maintain the contact resistance comparable to that of the combination of the conventional copper electric wire and the conventional connection terminal. Therefore, it is possible to avoid failures including heat generation due to the increase in contact resistance.
Consequently, this allows the same usage/handling as that of the conventional combination of copper electric wires and conventional connection terminals.
The connection terminal according to the present invention used for the aluminum electric wire, the connection device including the connection terminal, the method for manufacturing the connection device, the motor using the connection device, and the compressor using the motor and the blower using the motor, are applicable to the fields of application of electrical apparatus, including compressors and blowers, which employs conventional copper electric wires.
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/JP2013/002974 | 5/9/2013 | WO | 00 | 12/18/2013 |
