Motors and office equipment

Abstract

To prevent a winding lead wire from becoming brittle more easily and to increase its service life.SOLUTION: A motor includes a laminated core 5 fixed on a rotary shaft, a winding 3 wound on the laminated core 5, and a commutator terminal 2a connecting a lead portion 3a of the winding 3. A resin member 1 covers a side of the commutator terminal 2a and the lead portion 3a of the winding 3 without covering a surface of the commutator terminal 2a in a radial direction of the rotary shaft. It can be a piece of office equipment equipped with the motor and a control unit that controls the motor.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a motor used in office equipment and the like and office equipment.

Background Art

[0002] In a motor used in office equipment and the like, particularly a brush motor, disconnection of the connection portion between the winding and the commutator terminal may be a problem. Patent Document 1 describes using a metal sleeve to prevent disconnection by not applying bending to the connection portion between the winding and the commutator terminal and to facilitate positioning of the commutator on the rotor shaft.

[0003] Further, Patent Document 1 also shows a configuration in which the entire connection portion between the winding and the commutator terminal is covered with an adhesive as a conventional technique.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] As shown in Patent Document 1, the weakening of the winding lead wire has a great influence on the life of the motor. The present invention more easily prevents the weakening of the winding lead wire and aims to extend the life.

Means for Solving the Problems

[0006] In order to solve the above problems, the motor of the present invention includes a laminated core fixed on a rotating shaft, a winding wound around the laminated core, and a commutator terminal connecting a lead portion of the winding, and has a resin member covering a side surface of the commutator terminal and the lead portion of the winding without covering a surface of the commutator terminal in a direction orthogonal to an axial direction of the rotating shaft.

[0007] Further, in order to solve the above problems, the motor of the present invention includes a laminated core fixed on a rotating shaft, a winding wound around the laminated core, and a commutator terminal connecting a lead portion of the winding, wherein the winding and the commutator are connected by solder, and it is characterized by having a resin member covering a side surface of the solder and a lead portion of the winding without covering a surface of the commutator terminal in a radial direction of the rotating shaft.

Effects of the Invention

[0008] The present invention can more easily prevent the weakening of the winding lead wire and achieve a longer service life.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Modes for Carrying Out the Invention

[0010] FIG. 1 is a diagram showing a motor rotor. Between the laminated core 5 fixed to the rotating shaft 4 and the winding 3 wound around the laminated core 5, an output-side insulating material 6 for the purpose of electrical insulation on the output side of the motor is provided. Also, a counter-output-side insulating material 6a for the purpose of electrical insulation on the counter-output side of the motor is provided between the laminated core 5 and the winding 3 from the counter-output side of the rotating shaft 4. When the output-side insulating material 6 and the counter-output-side insulating material 6a are not provided, the laminated core 5 and the rotating shaft 4 may be coated with a coating such as insulating paint.

[0011] The commutator 2 is fixed to the rotating shaft 4, and the winding lead wire 3a is electrically and mechanically coupled to the commutator terminal 2a by electric resistance welding. When electric resistance welding is performed, the insulating coating of the winding lead wire 3a is melted, and the winding lead wire 3a and the commutator terminal 2a are electrically connected. FIG. 2 is an enlarged view of the periphery of the commutator terminal 2a. FIG. 3 is an A-A cross section of the commutator terminal 2a viewed axially. The commutator terminals 2a are provided at six locations in the circumferential direction to allow current to flow through each phase of the motor, and are separated by grooves for insulating each of them.

[0012] FIG. 4 is an enlarged view of the periphery of the commutator terminal 2a before applying the adhesive 1. When the winding 3 is arranged in a state where the commutator terminal 2a spreads radially with respect to the axial direction of the rotating shaft 4, and the commutator terminal 2a is bent toward the rotating shaft 4 to sandwich the winding 3 and electric resistance welding is performed, the insulating coating of the winding lead wire 3a melts as shown in FIG. 4 and an insulating coating melted portion 3b appears. In order to ensure a reliable electrical connection, that is, to melt the insulating coating of the winding lead wire 3a within the range of the commutator terminal 2a, as shown in FIG. 3, electric resistance welding is performed so that the insulating coating melted portion 3b of the winding lead wire extends from the commutator terminal 2a with a margin of approximately 0.5 mm in length.

[0013] The winding 3 mainly uses copper wire with an insulating coating. Due to the rotation of the motor itself and external factors, vibration occurs in the rotor, that is, in the winding 3. The vibration causes continuous breakage from the crystal grain boundaries of the copper wire, and finally leads to breakage, that is, disconnection. The winding lead wire 3a is in a string shape and is thus easy to vibrate, and the stress due to vibration concentrates at the commutator terminal boundary portion 3c of the winding lead wire, which is a mechanical coupling point.

[0014] The commutator terminal boundary portion 3c of the winding lead wire is the mechanical deformation point by the aforementioned electric resistance welding and at the same time the heating point by the electric resistance welding, and its toughness has deteriorated compared to the initial stage.

[0015] In addition, the insulation coating dissolution portion 3b of the winding lead wire including the commutator terminal boundary portion 3c of the winding lead wire is exposed to the atmosphere, so it is a location where oxidation progresses.

[0016] Furthermore, since the commutator terminal 2a is a heat generation point due to the applied current for motor drive, the commutator terminal boundary portion 3c of the immediately adjacent winding lead wire is easily affected by heating and repeated thermal fluctuations, and is a location where toughness deterioration due to oxidation and heat is promoted. The commutator terminal boundary portion 3c is a location with inferior mechanical strength due to the absence of an insulation coating.

[0017] Here, it is known that the higher the heating temperature, the longer the heating time, and the more the number of heating repetitions, the more the oxidation and deterioration of the copper wire are promoted.

[0018] That is, in the winding 3, the commutator terminal boundary portion 3c of the winding lead wire is the weakest location and is most likely to finally break, that is, become disconnected.

[0019] Therefore, as shown in FIG. 2, by covering the insulation coating dissolution part 3b of the winding lead wire and the commutator terminal boundary part 3c of the winding lead wire with the adhesive 1 (resin member) over the part where the insulation coating remains, and applying it to the commutator 2 including the side surface of the commutator terminal 2a, it is possible to restore the mechanical strength, change the stress concentration point of vibration, and prevent oxidation. That is, it is possible to achieve a longer life by eliminating the weakest part where a plurality of elements leading to disconnection are concentrated. At this time, if the glass transition point of the adhesive is higher than the glass transition point of the insulation coating of the lead wire, it can be made more durable against heating. At this time, the adhesive 1 partially covers the side surfaces on both sides in the circumferential direction of the commutator terminal 2a, and covers from the insulation coating dissolution part 3b of the lead part connected to the commutator terminal 2a over the insulation coating. By making the area of the adhesive 1 smaller than the side surface of the commutator terminal 2a, it is easier to attach the varistor described later, and the amount of the resin member can also be reduced. The adhesive 1 may be applied wider than the side surface on one side of the commutator terminal 2a, may partially reach the surface of the commutator terminal 2a in the direction (radial direction) orthogonal to the axial direction of the rotating shaft 4, and does not have to cover the surface of the commutator terminal 2a.

[0020] Since the application part of the adhesive 1 is an electrically connected and heat-generating part as described above, for example, in order to prevent an increase in the conductive area so as not to increase the possibility of electrical failures such as electrostatic breakdown, it is an electrical insulator, and in the case of thermal failure, in addition to having heat resistance higher than the dissolution temperature of the insulation coating of the winding 3, an adhesive having excellent thermal strength and being a thermosetting adhesive is desirable. Also, in order to cure quickly when applied partially, it is preferably a UV-curable resin, and in order to prevent uncured parts from remaining, it is preferably thinner than the radial thickness of the commutator terminal. Also, in order to suppress weight increase, it is good to provide it in a range narrower than the axial length of the commutator terminal. In this embodiment, a UV-curable resin adhesive is used, but as long as it is a resin member that covers the side surface of the commutator terminal and the lead part of the winding without covering the surface of the commutator terminal in the radial direction of the rotating shaft, it does not have to be an adhesive. Also, the adhesive 1 may be a thermosetting resin, or may be a UV-curable and thermosetting resin.

[0021] Also, the adhesive 1 applied to each terminal is located near the rotation axis 4 and on concentric circles with each other, at the same height in the length direction of the rotation axis 4, and equally spaced in the rotation direction. In addition, since the amount of the adhesive 1 is small, it is difficult to cause a large increase in weight, and the influence on the motor characteristics due to the moment of inertia is negligible. That is, if it has a surface inclined in a direction intersecting the cylindrical surface in the rotation direction of the commutator and is provided by being divided into both side surfaces of the commutator terminal respectively, the weight of the adhesive 1 can be suppressed and the influence on the motor characteristics can be reduced.

[0022] Furthermore, when using an adhesive, in the motor manufacturing process, the adhesive process can be easily added without changing the existing process. The fact that the amount of the adhesive 1 is small makes it possible to suppress an increase in the production tact.

[0023] FIG. 5 shows another embodiment, which is a diagram showing an example in which the adhesive 1 is connected to adjacent poles, and the same effect as that of FIG. 2 can be obtained.

[0024] FIG. 6 shows, as another embodiment, a commutator terminal portion of an assembly method in which the winding lead wire 3 is mechanically coupled and electrically connected to the commutator terminal 32a with "solder" or the like without bending the commutator terminal 32a of the commutator 32. However, it is a diagram showing the state before applying the adhesive. As described in the above embodiments, the adhesive 31 covers the insulation coating dissolution portion of the winding lead wire and the boundary portion such as "solder" corresponding to the commutator terminal boundary portion here with the insulation coating, so that the same effect as that of FIG. 2 can be obtained. That is, regardless of the style of the commutator 2, the same effect as that of FIG. 2 can be obtained. At this time, the side surface of the commutator terminal indicates the portion in contact with the lead wire 3.

[0025] FIG. 7 is a view after fixing the winding lead wire 3 to the commutator terminal 32a in FIG. 6 with solder 30, covering the insulation film dissolution parts on both side surfaces of the solder 30 with an adhesive 31, and curing the adhesive 31. The insulation coating of the winding lead wire is made of a resin having a melting temperature lower than that of the solder 30. With this configuration, current can flow through the winding 3 without performing electric resistance welding. The solder is configured to cover the surface of the commutator terminal 32a in the rotational axis direction, but partially, soldering can be performed and the adhesive 31 can also be applied to the surface of the commutator terminal 32a in the rotational axis direction.

[0026] FIG. 8 is an example of a brush-equipped motor using the present invention. In addition to the rotor shown in FIG. 1, a thrust washer 9 is attached to the output side of the rotating shaft, a varistor 14, a lubricant stop washer 15, and a lubricant reservoir washer 16 are attached to the non-output side of the rotating shaft, forming a rotor.

[0027] The varistor 14 is used to protect a circuit with a non-linear resistance. After curing the adhesive 1, soldering is performed so that the varistor 14 is electrically contacted with the surface of the commutator terminal 2a in the direction (radial direction) orthogonal to the axial direction of the rotating shaft. This soldering is provided for the varistor 14 for each surface of the commutator terminals 2a, and the respective solders are provided so as not to contact the adjacent solders. The varistor 14 is electrically contacted with the surface of the commutator terminal in the radial direction of the rotating shaft in order to be easily attached to a position where an electrical contact is easily made. Therefore, as described above, by not covering the surface of the commutator terminal in the radial direction of the rotating shaft with the adhesive 1, the varistor 14 can be easily attached to the commutator terminal without increasing its size in the radial direction or making it into a complicated shape.

[0028] In Case 11, an output shaft side bearing 10, a magnet 7, a magnet 7a paired with the magnet 7, and a magnet fixing member 8 for fixing the magnets 7 and 7a within the case 11 are attached. The case 11, the magnets 7, 7a, and the magnet fixing member 8 form a case unit. Further, an auxiliary yoke 12 is attached to the outside of the case 11. To the brush holder 18, a counter output shaft side bearing 17, brushes 19 and a brush 19a paired with the brush 19, brush arms 20 and a brush arm 20a paired with the brush arm 20, vibration isolators 21 and a vibration isolator 21a paired with the vibration isolator 21, external connection terminals 22 and an external connection terminal 22a paired with the external connection terminal 22 are attached. A pair of brush arm units composed of the counter output shaft side bearing 17, the brushes 19, 19a, the brush arms 20, 20a, the vibration isolators 21, the external connection terminals 22, 22a are attached to the brush holder 18 to form a brush holder unit. The aforementioned rotor passes through the output shaft side bearing 10 and the counter output side bearing 17, and the aforementioned brush holder unit fits into the case 11 and is fixed by bending the outer peripheral end portion of the case 11 at a plurality of locations. A pulley 13 is attached to the output shaft side tip of the rotating shaft 4.

[0029] FIG. 9 shows an example of an inkjet recording apparatus incorporating the brush motor described in the embodiment of the present invention. In FIG. 9, a blade 61 serves as a wiping member, one end of which is held by a blade holding member to form a fixed end and has a cantilever form. The blade 61 is disposed at a position adjacent to the recording area by the recording head 65, and in this example, is held in a form protruding into the movement path of the recording head 65. The cap 62 is disposed at a home position adjacent to the blade 61 and moves in a direction perpendicular to the movement direction of the recording head to contact the discharge port surface for capping. Further, an absorber 63 is provided adjacent to the blade 61 and is held in a form protruding into the movement path of the recording head 65, similar to the blade 61. The discharge recovery unit 64 is constituted by the blade 61, the cap 62, and the absorber 63, and moisture, dust, etc. are removed from the ink discharge port surface by the blade 61 and the absorber 63.

[0030] The recording head 65 has ejection energy generating means and performs recording by ejecting ink onto a recording material facing the ejection port surface where the ejection ports are arranged. The carriage 66 mounts the recording head 65 and moves the recording head 65. The carriage 66 is slidably engaged with the guide shaft 67, and a part of the carriage 66 is connected (not shown) to a belt 69 driven by a motor 68. Thereby, the carriage 66 can move along the guide shaft 67, and the recording head 65 can move over the recording area and the area adjacent thereto. A paper feeding unit 51 for inserting the recording material is provided, and the paper feed roller 52 is driven by a motor (not shown). With these configurations, the recording material is fed to a position facing the ejection port surface of the recording head 65, and as the recording progresses, it is discharged to a discharge unit where a discharge roller 53 is arranged.

[0031] In the above configuration, when the recording head 65 returns to the home position at the end of recording or the like, the cap 62 of the ejection recovery unit 64 has retracted from the movement path of the recording head 65, but the blade 61 protrudes into the movement path. As a result, the ejection port surface of the recording head 65 is wiped. Incidentally, when the cap 62 abuts against the ejection surface of the recording head 65 to perform capping, the cap 62 moves so as to protrude into the movement path of the recording head. When the recording head 65 moves from the home position to the recording start position, the cap 62 and the blade 61 are in the same positions as those at the time of wiping described above. As a result, also in this movement, the ejection port surface of the recording head 65 is wiped. The above-described movement of the recording head to the home position occurs not only at the end of recording or during ejection recovery, but also at predetermined intervals while the recording head moves over the recording area for recording, and the recording head moves to the home position adjacent to the recording area, and the above wiping is performed along with this movement.

[0032] As the motor 68 of the inkjet recording apparatus described above, when a brush motor according to the present invention is used and the voltage is varied like PWM control to perform position control of the recording head 65, printing with good durability and high accuracy can be performed. Further, a brush motor according to the present invention may be used for a paper feed motor which is another drive source. At this time, the drive of the motor is controlled by a control unit (not shown). In a motor driven by PWM, since the number of vibrations due to the acceleration of the voltage rise and fall by PWM control is very large and its durability often becomes a problem, the application of the present invention is particularly effective.

[0033] Further, it may be used for a pump unit of a discharge recovery unit 64 of an ink head (not shown), may be used for a drive unit of a scanner in which a reading head moves in the main scanning direction, and may be used for a motor of a multifunction device in which a scanner and a printer are integrated. Further, it may be used for a paper feed motor of a scanner that reads a conveyed document. The motor of the present invention may be used as a drive source for office equipment other than scanners and printers.

Explanation of reference numerals

[0034] 1 Adhesive (resin member) 2, 32 Commutator 2a, 32a Commutator terminal 3 Coil 3a Coil lead wire 3b Insulation coating dissolution part of coil lead wire 3c Commutator terminal boundary part of coil lead wire 4 Rotating shaft 5 Laminated core 11 Case 12 Auxiliary yoke 13 Pulley 14 Varistor

Claims

1. A laminated core fixed on a rotating shaft; a winding wound around the laminated core; a commutator terminal to which the lead portion of the winding is connected, A motor comprising: a resin member that covers the side surfaces of the commutator terminals and the lead portions of the windings, but does not cover the surfaces of the commutator terminals in the radial direction of the rotating shaft.

2. 2. The motor according to claim 1, wherein the resin member is provided on one side surface of the commutator terminal and on a melting portion of an insulating coating of the lead portion connected to the one side surface.

3. 3. The motor according to claim 1, wherein the resin member is an electrical insulator and is a thermosetting resin.

4. 4. The motor according to claim 1, wherein a varistor is electrically connected to a surface of the commutator terminal.

5. A laminated core fixed on a rotating shaft; a winding wound around the laminated core; a commutator terminal to which the lead portion of the winding is connected, the windings and the commutator terminals are connected by solder; a resin member that covers the side surface of the solder and the lead portion of the winding, without covering the surface of the commutator terminal in the radial direction of the rotating shaft.

6. 6. An office machine comprising: a motor according to claim 1; and a control unit that controls the motor.

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