JP2018170839A - Electric actuator and manufacturing method for electric actuator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric actuator in which operation of connecting a conductive member to an electric motor can be easily performed, and sealing between the conductive member and a case is not necessary.SOLUTION: The electric actuator comprises a drive unit having an electric motor 7, and a motion conversion mechanism unit that converts rotary motion of the drive unit to linear motion. The motion conversion mechanism unit comprises a nut that rotates in response to the rotary motion of the drive unit, and a screw shaft that is disposed on the inner circumference of the nut and that linearly moves in association with the rotation of the nut. In the electric actuator, a case 10 and a conductive member 19 formed integrally with the case 10 are provided. The conductive member 19 has an insertion portion 194. A motor terminal 7c of the electric motor 7 is inserted in the insertion portion 194 so as to be conductively connected.SELECTED DRAWING: Figure 10

Description

  The present invention relates to an electric actuator and a method for manufacturing the electric actuator.

  In recent years, in vehicles such as automobiles, electrification has progressed to save labor and reduce fuel consumption. For example, a system that uses the power of an electric motor to operate automatic transmissions, brakes, steering, etc. has been developed. Has been put on the market. As a so-called linear motion type electric actuator used for such applications, there is known one using a ball screw as a motion conversion mechanism for converting the rotational motion of a motor into a linear motion.

  For example, in Patent Document 1, in a linear motion type electric actuator that employs a ball screw as a motion conversion mechanism, there is a configuration in which an opening through which the wiring is passed is provided in the housing in order to connect the wiring of the motor to the drive circuit. It is disclosed.

Japanese Patent No. 5218817

  However, in the configuration as described in Patent Document 1, it is necessary to take out the wiring through the opening of the housing in the assembly process of the electric actuator, so that there is a problem that the number of assembling steps increases. In addition, foreign matter such as dust and water may enter the housing from the gap between the opening and the wiring, and in order to prevent this, a process for sealing the gap between the opening and the wiring is required. There was also a problem that the cost increased.

  In view of the above, an object of the present invention is to provide an electric actuator that can easily connect a conductive member to an electric motor and that does not require a sealing process between the conductive member and the case.

  As technical means for solving the above-mentioned problems, the present invention includes a drive unit having an electric motor and a motion conversion mechanism unit that converts the rotational motion of the drive unit into linear motion, and the motion conversion mechanism unit is driven. In a motor-driven actuator having a nut that rotates in response to the rotational movement of a portion, and a screw shaft that is arranged on the inner periphery of the nut and moves linearly as the nut rotates, a conductive member formed integrally with the case The conductive member has an insertion portion, and the motor terminal of the electric motor is inserted into the insertion portion and connected to be conductive.

  In the electric actuator according to the present invention, since the motor terminals can be connected to each other only by inserting the motor terminals into the insertion portion, the connection work between the conductive member and the motor terminals can be easily performed. Further, since the conductive member is formed integrally with the case, it is not necessary to separately perform a work of attaching the conductive member to the case, and the number of assembling steps can be reduced. In addition, by forming the conductive member integrally with the case, it is possible to prevent the occurrence of a gap between the conductive member and the case, as in the case where they are formed separately, so a sealing process for closing the gap is performed separately. Even without it, it is possible to prevent foreign matter from entering the case.

  In connecting the conductive member and the motor terminal, it is preferable to hold the motor terminal with the insertion portion interposed therebetween. Thus, by holding the motor terminal with the insertion portion sandwiched between the motor terminal and the conductive member, the connection strength against vibration and the like is improved.

  For example, the insertion portion has a bottom portion that contacts the first surface of the motor terminal, and a pair of pressing portions that rise from the bottom portion in a direction crossing the bottom portion and that contact the second surface opposite to the first surface of the motor terminal. Therefore, the motor terminal can be held between the bottom portion and the pressing portion.

  Moreover, in the structure which has a motor fitting part which a case fits with an electric motor, the fitting direction of the electric motor with respect to a motor fitting part and the insertion direction of the motor terminal with respect to an insertion part are made into the same direction. Thus, the fitting operation and the inserting operation can be performed by a series of operations, and workability is improved.

  In order to solve the above problems, the present invention includes a drive unit having an electric motor, and a motion conversion mechanism unit that converts the rotational motion of the drive unit into a linear motion, and the motion conversion mechanism unit rotates the drive unit. In a method of manufacturing an electric actuator having a nut that rotates in response to movement and a screw shaft that is arranged on the inner periphery of the nut and moves linearly as the nut rotates, a conductive member having an insertion portion is formed integrally with the case. The motor terminal of the electric motor is inserted into the insertion portion and connected to be conductive.

  As described above, since the motor terminals can be connected so as to be conductive only by inserting the motor terminals into the insertion portion, the connection work between the conductive member and the motor terminals is facilitated. In addition, since the conductive member is formed integrally with the case, the mounting work of the conductive member becomes unnecessary, the number of assembling steps can be reduced, and the occurrence of a gap between the conductive member and the case can be prevented. Intrusion of foreign matter into the case can be prevented without performing a sealing process to close the gap.

  Also, when inserting the motor terminal into the insertion part, by plastically deforming the insertion part, the motor terminal can be soldered to the conductive member, or the conductive member can be crimped to the motor terminal without being crimped. An insertion part and a motor terminal can be stuck. Thereby, the motor terminal and the conductive member are more firmly connected, and the connection strength against vibration and the like is improved.

  The conductive member and the case can be integrally formed by insert-molding the conductive member into the case.

  According to the present invention, it is possible to easily connect the conductive member to the electric motor. In addition, according to the present invention, since it is not necessary to perform a sealing process between the conductive member and the case, the manufacturing cost can be reduced.

It is a longitudinal section of the electric actuator concerning a 1st embodiment of the present invention. FIG. 2 is a partially exploded perspective view of the electric actuator shown in FIG. 1. FIG. 2 is a partially exploded perspective view of the electric actuator shown in FIG. 1. FIG. 2 is a partially exploded perspective view of the electric actuator shown in FIG. 1. It is a disassembled perspective view of the screw shaft in the state where the permanent magnet was attached. It is a perspective view of the 2nd case and a bus bar. It is sectional drawing of the insertion part before a motor terminal is inserted. It is an enlarged view of a motor terminal. It is an enlarged view of a motor terminal. It is a figure which shows the state by which the bus-bar and the motor terminal were connected. It is CC sectional view taken on the line of FIG. It is DD sectional view taken on the line of FIG.

  Hereinafter, the present invention will be described with reference to the accompanying drawings. In the drawings for explaining the present invention, components such as members and components having the same function or shape are denoted by the same reference numerals as much as possible, and once described, the description will be given. Omitted.

  FIG. 1 is a longitudinal sectional view of the electric actuator according to the first embodiment of the present invention, and FIG. 2 is an exploded perspective view of the electric actuator according to the first embodiment.

  As shown in FIG. 1, the electric actuator 1 according to the first embodiment includes a drive unit 2, a motion conversion mechanism unit 3 that converts a rotational motion of the drive unit 2 into a linear motion, and a linear motion of the motion conversion mechanism unit 3. And an operation unit 6 for operating an operation target not shown. The drive unit 2 of the present embodiment has an electric motor 7. The “axial direction” referred to below is a direction along the rotation center X of the electric motor 7 shown in FIG. In the following, for convenience in explaining the directionality in the axial direction, the side on which the drive unit 2 is disposed (the right side in FIG. 1) and the side on which the operation unit 6 is disposed (the left side in FIG. 1). Are referred to as one axial side and the other axial side, respectively.

  As shown in FIGS. 1 and 2, each of the drive unit 2 and the motion conversion mechanism unit 3 includes a member that constitutes a housing 1 </ b> A of the electric actuator 1. Specifically, the drive unit 2 is provided with a first case 9 that houses the electric motor 7 and a pair of bus bars 19 as conductive members that electrically connect a power source (not shown) and the electric motor 7. The motion conversion mechanism unit 3 includes a second case 10 and a third case 11 that houses a ball screw 12 as a motion conversion mechanism. The housing 1A is completed by combining and integrating the cases 9 to 11 arranged in a line in the axial direction using the bolt members 27 shown in FIG.

  In order to improve the sealing performance between adjacent cases, the flange portion 16 of the first case 9 and the flange portion 25 of the second case 10 and the flange portion 25 of the second case 10 and the flange portion 26 of the third case 11 are used. O-rings 28 and 29 are interposed between the two.

  The drive unit 2 includes an electric motor 7 that generates a driving force (rotational driving force), a first case 9 that houses the electric motor 7, a bus bar 19, and a second case 10 in which the bus bar 19 is provided. The first case 9 integrally includes a bottomed cylindrical case main body 15 and a flange portion 16 provided with an insertion hole for the bolt member 27 shown in FIG.

  The inner peripheral surface 15a of the case body 15 is gradually reduced in diameter from the other side in the axial direction (opening side of the case body 15) toward one side in the axial direction (bottom side of the case body 15). The outer periphery of the end on one side in the direction is in contact with the end on the one side in the axial direction of the inner peripheral surface 15a of the case main body 15 in a state avoiding contact with the surface. Moreover, the electric motor 7 has the protrusion part 7a fitted to the inner periphery of the motor fitting part 17 of the 2nd case 10 mentioned later. Therefore, the electric motor 7 is supported by the case main body 15 of the first case 9 and the motor fitting portion 17 of the second case 10. An O-ring 18 is interposed between the electric motor 7 and the inner bottom surface 15b of the case body 15 to prevent the electric motor 7 from rattling in the axial direction and external leakage of lubricant such as grease. .

  The second case 10 has a cylindrical case body 23, a cylindrical fitting portion 24 fitted to the inner periphery of the third case 11, and a protrusion 7a of the electric motor 7 fitted to the inner periphery. An annular motor fitting portion 17 and a flange portion 25 provided with an insertion hole for the bolt member 27 shown in FIG. 2 are integrally provided. Since the second case 10 integrally includes the fitting portion 24 and the motor fitting portion 17, the centering between the first case 9 to the third case 11 can be easily performed. The rotation center X and the rotation center of the nut 30 of the ball screw 12 described later can be easily matched.

  As shown in FIG. 3, a pair of bus bars 19 is provided on the case body 23 of the second case 10. One end 19a of each bus bar 19 protrudes in the axial direction from the case body 23 and is exposed to the outside, and the other end 19b protrudes in the radial direction from the case body 23 and is exposed to the outside. One end portion 19a protruding in the axial direction of each bus bar 19 is formed in a substantially cylindrical shape, and a pair of motor terminals 7c provided on the electric motor 7 is a shaft with respect to the one end portion 19a formed in the substantially cylindrical shape. The motor terminal 7c and each bus bar 19 are connected to each other by being inserted in the direction. Further, the other end 19b protruding in the radial direction of each bus bar 19 is connected to a power source (not shown).

  As shown in FIG. 1, the motion conversion mechanism unit 3 includes a ball screw 12 and a third case 11 in which the ball screw 12 is accommodated. The ball screw 12 includes a screw shaft 31 disposed coaxially (in series) with the output shaft 7 b of the electric motor 7, a nut 30 rotatably fitted to the outer periphery of the screw shaft 31 via a large number of balls 32, A top 33 as a circulation member is provided. A large number of balls 32 are filled between a spiral groove 30 a formed on the inner peripheral surface of the nut 30 and a spiral groove 31 a formed on the outer peripheral surface of the screw shaft 31, and a top 33 is incorporated. With such a configuration, when the screw shaft 31 moves back and forth (linear motion) in the axial direction as the nut 30 rotates, the ball 32 circulates between the spiral grooves 30a and 31a.

  A coupling 62 is provided on the output shaft 7 b of the electric motor 7 so as to be able to rotate integrally with the output shaft 7 b, and the electric motor 7 and the nut 30 of the ball screw 12 are connected via the coupling 62. As shown in FIG. 2, the coupling 62 has a flat surface 62a on the outer periphery, and is fitted and fixed to the inner peripheral surface 30b (see FIG. 1) on the other axial end side of the nut 30 by fitting or the like. . Thereby, the rotational driving force of the electric motor 7 is transmitted to the nut 30 via the coupling 62, and the nut 30 rotates in either the forward or reverse direction. On the other hand, the rotation of the screw shaft 31 is restricted by a detent described later. For this reason, when the nut 30 rotates in response to the rotational driving force of the drive unit 2, the screw shaft 31 moves forward and backward in the axial direction according to the rotational direction of the nut 30. The end of the screw shaft 31 on the other side in the axial direction functions as an operation unit (actuator head) 6 that operates an operation target (not shown). Therefore, the operation target is operated in the axial direction as the screw shaft 31 moves back and forth in the axial direction.

  The third case 11 includes a large diameter cylindrical portion 35, a small diameter cylindrical portion 36 located on the other axial side of the large diameter cylindrical portion 35, and an annular flange portion provided with an insertion hole for the bolt member 27 shown in FIG. 26 integrally. An inner peripheral surface 37 of the large-diameter cylindrical portion 35 is formed in a cylindrical surface having a constant diameter, and the nut 30 is rotatably supported on the inner peripheral surface 37 with respect to the housing 1A (third case 11). Bearings (ball bearings) 13 and 14 are attached and fixed apart in the axial direction.

  The third case 11 has a metallic cylindrical member 38 disposed on the inner periphery of the large-diameter cylindrical portion 35, and the inner peripheral surface 37 to which the bearings 13 and 14 (outer rings) are attached and fixed is as follows. It is comprised by the internal peripheral surface of the cylindrical member 38. FIG. An annular portion 39 extending inward in the radial direction is integrally provided at the other axial end of the tubular member 38, and the annular portion 39 and the bearing 13 are opposed to each other in the axial direction. A wave washer 42, which is an annular elastic member that has been compressed and deformed, and an annular spacer washer 43 are interposed. Further, the bearing 14 positioned on one side in the axial direction is urged toward the other side in the axial direction by the fitting portion 24 of the second case 10. With the above configuration, axial preload is applied to the bearings 13 and 14 formed of rolling bearings.

  As shown in FIG. 1, a cylindrical slide bearing 40 formed of sintered metal and having a screw shaft 31 inserted in the inner periphery is provided on the inner periphery of the small-diameter cylindrical portion 36 constituting the third case 11. ing. A sliding surface 34 on which the screw shaft 31 can slide is provided on the inner peripheral surface of the slide bearing 40. The internal pores of the sliding bearing 40 made of a sintered metal porous body are preferably impregnated with a lubricant such as grease or lubricating oil. In this way, an oil film can be formed between the inner peripheral surface (sliding surface 34) of the slide bearing 40 and the outer peripheral surface of the screw shaft 31, so that the screw shaft 31 can be smoothly linearly moved. it can. A retaining ring 41 for positioning the slide bearing 40 in the axial direction is fixed at a predetermined position in the axial direction of the screw shaft 31.

  In the present embodiment, an anti-rotation function of the screw shaft 31 is given to the inner peripheral surface (sliding surface 34) of the slide bearing 40. More specifically, as shown in FIG. 4, the sliding surface 34 includes one flat surface 34 a provided in a partial region in the circumferential direction and an arc surface (partial cylindrical surface) 34 b. On the other hand, in the sliding region 31b that slides with the sliding surface 34 of the outer peripheral surface of the screw shaft 31, a flat surface portion 31b1 that faces the flat surface 34a of the sliding surface 34 and a partial cylinder that faces the partial cylindrical surface 34b. A surface portion 31b2 is provided.

  The third case 11 of the present embodiment having the above configuration is a resin injection-molded product using the cylindrical member 38 and the slide bearing 40 as insert parts. In this case, the third case 11 is provided with a hole 11a so as to follow the outer peripheral surface of the positioning pin in which the cylindrical member 38 is positioned in the mold in the axial direction. Alternatively, after the resin-made third case 11, the metal cylindrical member 38, and the sintered metal slide bearing 40 are individually manufactured, they may be fixed by appropriate means.

  As shown in FIG. 1, a boot 44 is installed between the small diameter cylindrical portion 36 of the third case 11 and the screw shaft 31 to prevent foreign matter from entering the third case 11. The boot 44 is made of resin or rubber, and integrally includes a large-diameter cylindrical portion 44a and a small-diameter cylindrical portion 44b, and a bellows portion 44c interposed between the cylindrical portions 44a and 44b. The large-diameter cylindrical portion 44a and the small-diameter cylindrical portion 44b of the boot 44 are fastened and fixed to the outer peripheral surface of the small-diameter cylindrical portion 36 of the third case 11 and the outer peripheral surface of the screw shaft 31 by using boot bands 45 and 46, respectively. A boot cover 47 covering the boot 44 is disposed on the outer periphery of the boot 44, and the boot cover 47 is attached to, for example, the third case 11 adjacent in the axial direction.

  Further, the electric actuator 1 is provided with a position detection device for detecting the axial position (the amount of movement in the axial direction) of the screw shaft 31. As shown in FIG. 1, the position detection device includes a permanent magnet 53 as a sensor target provided on the screw shaft 31 and a magnetic sensor 54 as a position detection sensor provided on the boot cover 47. As the magnetic sensor 54, any type can be used, and among them, a type capable of detecting the direction and magnitude of the magnetic field using the Hall effect, such as Hall IC and linear Hall IC, can be preferably used.

  As shown in FIGS. 1 and 4, the magnetic sensor 54 is formed integrally with a sensor substrate 55, and the sensor substrate 55 is fixed to a sensor case 57 by a connecting member 56. Then, by attaching a sensor assembly 58 in which the sensor substrate 55 is attached to the sensor case 57 to a sensor attachment portion 47 a provided at a predetermined position in the circumferential direction of the boot cover 47, the magnetic sensor 54 is arranged in the circumferential direction of the boot cover 47. While being installed at a predetermined position, it is in a state of facing the permanent magnet 53 through the boot 44 and the boot cover 47. In this case, the magnetic sensor 54 is covered with the boot cover 47 and the sensor case 57 as shown in FIG. The sensor case 57 and the boot cover 47 that cover the periphery of the magnetic sensor 54 are both formed of a nonmagnetic material such as a resin material.

  FIG. 5 shows an exploded perspective view of the sensor target unit 59 including the permanent magnet 53 and the screw shaft 31. As shown in FIG. 5, a notch 31c is formed at a predetermined position in the axial direction of the screw shaft 31, and a sensor target unit 59 is attached to the notch 31c.

  The sensor target unit 59 includes a permanent magnet 53 and first and second magnet holders 60 and 61 that hold the permanent magnet 53. The first magnet holder 60 is formed in a substantially arc shape as a whole, and has a fitting claw 60 a fitted in the notch 31 c of the screw shaft 31 and a housing portion 60 b that can house the permanent magnet 53. The housing part 60 b has an end on the other axial side opening in the end face on the other axial side of the first magnet holder 60. Then, the permanent magnet 53 is inserted into the accommodating portion 60b of the magnet holder 60 from the opening side, and then the second magnet holder 61 formed in an arc shape so as to close the opening is attached to the screw shaft 31. It is positioned in the axial direction by fitting into the notch 31c.

  The material of the first and second magnet holders 60 and 61 is basically arbitrary. For example, when the influence of the permanent magnet 53 on the magnetic field formed around the permanent magnet 53 is taken into consideration, each of the magnet holders 60 and 61 is preferably made of a non-magnetic material, and the attachment property (fit) of the magnet holders 60 and 61 to the screw shaft 31 is good. In consideration of the elastic deformability of the joint claw 60a, it is preferable to use resin.

  Since the position detection device is configured as described above, when the screw shaft 31 moves back and forth in the axial direction, the relative position of the permanent magnet 53 in the axial direction with respect to the magnetic sensor 54 changes. The magnetic field at the location also changes. The magnetic sensor 54 detects a change in the magnetic field (for example, the direction and strength of the magnetic flux density), and acquires the axial position of the permanent magnet 53 and, in turn, the axial position of the screw shaft 31 (operation unit 6).

  Hereinafter, regarding the electric actuator 1 according to the present embodiment, the configuration of the bus bar 19 and the method of connecting the bus bar 19 and the motor terminal 7c will be described in detail.

  As shown in FIG. 6, the pair of bus bars 19 is configured by bending a band-shaped member made of a metal material such as brass or copper into a predetermined shape, which is formed with respect to the second case 10 made of resin. It is integrally formed with the second case 10 by insert molding.

  Each bus bar 19 is embedded in the case main body 23 of the second case 10, and extends in the radial direction of the case main body 23 from a circumferential extending portion 191 that extends in the circumferential direction of the case main body 23 and one end portion of the circumferential extending portion 191. A radially extending portion 192 that protrudes outward and an axially extending portion 193 that extends from the other end of the circumferentially extending portion 191 in the axial direction of the case body 23 and protrudes outward. A portion on the front end side of the radially extending portion 192 (a portion exposed outside the case main body 23) is a portion connected to a power source (not shown). On the other hand, the portion on the tip side of the axially extending portion 193 (the portion exposed to the outside of the case body 23) is a portion connected to the motor terminal, and here, a substantially cylindrical shape into which the motor terminal is inserted. An insertion portion 194 is provided.

  The insertion portion 194 includes a bottom portion 194a and a pair of pressing portions 194b that rise from the bottom portion 194a in a direction crossing the bottom portion 194a. The pair of pressing portions 194b are provided with a gap G (see FIG. 7) therebetween in the width direction of the bottom portion 194a. Further, the front end side of each pressing portion 194b is bent in an arc shape or a curved shape so as to approach each other, and these front end portions are spaced H in the height direction with respect to the bottom portion 194a (see FIG. 7). It is arranged so as to face each other with a gap. In this way, the pair of pressing portions 194b are provided with a gap G in the width direction, and the tip portions of the pressing portions 194b are arranged with a gap H in the height direction with respect to the bottom portion 194a. As a result, an insertion space J into which the motor terminal is inserted is formed inside the insertion portion 194.

  Further, the gap G in the width direction and the gap H in the height direction of the insertion space J are set as follows with respect to the width dimension and the thickness dimension of the motor terminal.

  First, the gap G in the width direction of the insertion space J is set larger than the width dimension W of the motor terminal 7c shown in FIG. On the other hand, the interval H in the height direction of the insertion space J is formed smaller than the thickness dimension T1 of the motor terminal 7c shown in FIG. Further, as shown in FIG. 9, the motor terminal 7c is provided with a convex portion 7e protruding in the thickness direction, and the thickness of the insertion portion J is larger than the thickness T2 of the portion where the convex portion 7e is provided. The interval H in the height direction is set small.

  As described above, the interval H in the height direction of the insertion space J is set to be smaller than the thickness dimensions T1 and T2 of each part of the motor terminal 7c. When inserted into the insertion portion 194, the insertion portion 194 is plastically deformed by the insertion (press-fit) of the motor terminal 7c.

  That is, as shown in FIG. 11, the insertion portion 194 is plastically deformed by being expanded in the height direction from the state shown by the broken line in the drawing to the state shown by the solid line. FIG. 11 is a cross-sectional view taken along the line CC in FIG. 10 where the insertion portion 194 is cut at a location where the convex portion 7e of the motor terminal 7c is not provided.

  Further, as shown in FIG. 12 (a cross-sectional view taken along the line D-D in FIG. 10), the insertion portion 194 is expanded in the thickness direction at the portion where the convex portion 7 e of the motor terminal 7 c is provided. In addition, when the convex portion 7e bites into the bottom portion 194a of the insertion portion 194, the bottom portion 194a is plastically deformed, and a concave portion 194c is formed in the bottom portion 194a.

  Thus, in the electric actuator according to the present embodiment, the insertion portion 194 of the bus bar 19 is plastically deformed by the insertion of the motor terminal 7c, whereby the insertion portion 194 and the motor terminal 7c can be brought into close contact with each other. 19 and the electric motor 7 can be reliably connected so as to be conductive. In the connected state, the motor terminal 7c is held by being inserted by the insertion portion 194. That is, in the connected state, the bottom portion 194a of the insertion portion 194 is in contact with one surface (first surface) in the thickness direction of the motor terminal 7c, and a pair with respect to the opposite surface (second surface). Therefore, the motor terminal 7c is held between the bottom portion 194a and the pressing portion 194b. Thereby, the motor terminal 7c and the bus bar 19 are firmly connected, and the connection strength against vibration and the like is improved.

  Furthermore, in the location where the convex part 7e of the motor terminal 7c is provided, the convex part 7e bites into the bottom part 194a of the insertion part 194, whereby the adhesion between the motor terminal 7c and the bus bar 19 is further improved. In addition, since the convex portion 7e of the motor terminal 7c and the concave portion 194c provided on the bottom portion 194a are engaged, it is possible to suppress a deviation between the motor terminal 7c and the insertion portion 194 due to vibration and the like. A stable connection state can be maintained over a long period of time.

  As described above, in the electric actuator according to the present embodiment, simply inserting the motor terminal 7c into the insertion portion 194 of the bus bar 19 allows the insertion portion 194 to be plastically deformed so that both members are brought into close contact with each other. A process of soldering the terminal 7c to the bus bar 19 or crimping the bus bar 19 to the motor terminal 7c is unnecessary, and the connection work can be easily performed.

  Further, in the electric actuator according to the present embodiment, the bus bar 19 is formed integrally with the second case 10, so that the mounting work of the bus bar 19 with respect to the second case 10 does not have to be performed separately, and the assembly man-hour is reduced. Can be reduced. Further, since the bus bar 19 is formed integrally with the second case 10, it is possible to prevent the occurrence of a gap between the bus bar and the case as in the case where they are formed separately. Accordingly, it is possible to prevent foreign matter from entering the case without separately performing a sealing process for closing the gap, so that the manufacturing cost can be reduced.

  Further, in the present embodiment, the fitting direction of the electric motor 7 with respect to the motor fitting portion 17 of the second case 10 and the insertion direction of the motor terminal 7c with respect to the insertion portion 194 are the same direction (axial direction). It is configured. Therefore, when the electric motor 7 is fitted to the motor fitting portion 17, the motor terminal 7c can be inserted into the insertion portion 194, and the fitting operation and the insertion operation can be performed by a series of operations. , Workability is improved.

  As mentioned above, although embodiment of the electric actuator which concerns on this invention was described, the electric actuator which concerns on this invention is not restricted to the above-mentioned embodiment. For example, the insertion portion is not limited to plastic deformation due to insertion of a motor terminal, and may be elastically deformed. Also in this case, the elastically deformed insertion portion is brought into close contact with the motor terminal, so that they can be connected in a conductive manner.

  In the above-described embodiment, the connection structure and the connection method of the conductive member for power supply (bus bar 19) have been described. However, the connection structure and the connection method are not limited to the conductive member for power supply, The present invention can also be applied to a control signal conductive member used to send a signal to and from an electric motor.

  Moreover, the electric actuator according to the present invention may include a speed reducer that decelerates and transmits a driving force (rotation) from the electric motor to the ball screw. As the speed reducer, for example, a planetary gear speed reducer, a traction drive type planetary speed reducer (planet roller speed reducer), or other various speed reducers can be employed.

  Further, in the above-described embodiment, the ball screw 12 is employed as the motion conversion mechanism unit 3, but instead of the ball screw 12, a so-called slide screw in which a nut is assembled to the screw shaft without using a ball is used. It may be adopted.

DESCRIPTION OF SYMBOLS 1 Electric actuator 2 Drive part 3 Motion conversion mechanism part 7 Electric motor 7c Motor terminal 9 1st case 10 2nd case 11 3rd case 12 Ball screw 17 Motor fitting part 19 Bus bar (conductive member)
194 Insertion part 194a Bottom part 194b Holding part

Claims (7)

A drive unit having an electric motor; and a motion conversion mechanism unit that converts the rotational motion of the drive unit into a linear motion; and the motion conversion mechanism unit rotates by receiving the rotational motion of the drive unit; In the electric actuator having a screw shaft that is arranged on the inner periphery of the nut and linearly moves with the rotation of the nut,
Case and
A conductive member formed integrally with the case;
The conductive member has an insertion portion;
An electric actuator, wherein a motor terminal of the electric motor is inserted into the insertion portion so as to be conductive.   The electric actuator according to claim 1, wherein the motor terminal is held by the insertion portion. The insertion portion includes a bottom portion that contacts the first surface of the motor terminal, and a pair of contacts that rises from the bottom portion in a direction intersecting the bottom surface and contacts a second surface opposite to the first surface of the motor terminal. A holding part,
The electric actuator according to claim 2, wherein the motor terminal is held by the bottom portion and the pressing portion. The case has a motor fitting portion fitted with the electric motor,
The electric actuator according to any one of claims 1 to 3, wherein a fitting direction of the electric motor with respect to the motor fitting portion and an insertion direction of the motor terminal with respect to the insertion portion are set in the same direction. A drive unit having an electric motor; and a motion conversion mechanism unit that converts the rotational motion of the drive unit into a linear motion; and the motion conversion mechanism unit rotates by receiving the rotational motion of the drive unit; In the manufacturing method of the electric actuator having a screw shaft that is arranged on the inner periphery of the nut and linearly moves with the rotation of the nut,
A conductive member having an insertion part is formed integrally with the case,
A method of manufacturing an electric actuator, wherein a motor terminal of the electric motor is inserted into the insertion portion and connected to be conductive.   The method for manufacturing an electric actuator according to claim 5, wherein when the motor terminal is inserted into the insertion portion, the insertion portion is plastically deformed so that the insertion portion and the motor terminal are brought into close contact with each other.   The method for manufacturing an electric actuator according to claim 5, wherein the conductive member is insert-molded with respect to the case.

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