JP2022126951A - Linear drive device - Google Patents

Abstract

To provide a linear drive device including a position detection mechanism for detecting the location of a movable body in the axial direction of a feed screw shaft and capable of suppressing the variation of the mounting location of a detector body of the position detection mechanism with respect to a frame of a motor fixed to an upper device in which the linear drive device is installed.SOLUTION: The linear drive device includes a motor having a feed screw shaft and a position detection mechanism for detecting the position of a movable body 3 in the axial direction of the feed screw shaft. The motor includes a frame 14 that is fixed to an upper device in which the linear drive device is installed. On the detector body of the position detection mechanism, positioning protrusions 32a, 32b are formed for positioning the detector body with respect to the frame 14. On the frame 14, positioning holes 14g, 14h are formed into which the positioning protrusions 32a, 32b are inserted.SELECTED DRAWING: Figure 4

Description

The present invention relates to a linear drive device that rotates a feed screw shaft to move a movable body linearly.

Conventionally, a motor having a feed screw shaft (lead screw) with a helical groove formed on the outer peripheral surface, a movable body that moves linearly along the feed screw shaft, and an origin position in the moving direction of the movable body are detected. and a position sensor are known (see, for example, Patent Document 1). In the linear drive device described in Patent Document 1, the motor includes a rotor having a rotating shaft on which a feed screw shaft is formed and a driving magnet, and a stator having a driving coil and arranged on the outer peripheral side of the driving magnet. , and a frame to which the output end of the stator is fixed.

In the linear drive device described in Patent Document 1, the frame includes a flat plate-shaped frame body, a first supporting portion that rises at right angles from the output side end of the frame body, and a second support portion that rises at right angles from the counter-output side end of the frame body. It is composed of a support part. The frame main body has a hole for fixing the linear drive device to a host device (mating device) on which the linear drive device is mounted, and the frame is fixed to the host device. A bearing that supports the output-side end of the feed screw shaft is attached to the first support. An output-side end face of the stator is fixed to the second support portion. The movable body is arranged between the first support and the second support in the axial direction of the feed screw shaft.

Further, in the linear drive device described in Patent Document 1, the motor includes terminal pins to which the drive coils are electrically connected. One end of the terminal pin is fixed by soldering to the power supply board. The power supply board is attached to the board holding member. The substrate holding member is attached to the second support portion of the frame. The position sensor is attached to the power supply board. That is, the position detector is attached to the frame via the power supply board and the board holding member. The position detector detects the origin position of the movable body on the counter-output side.

JP 2019-54648 A

In the linear drive device disclosed in Patent Document 1, the position detector is attached to the frame via the power supply board and the board holding member. Therefore, in this linear drive device, there are variations in individual parts of the power supply board and the board holding member, variations in the mounting position of the board holding member on the frame, variations in the mounting position of the power supply board on the board holding member, and variations in the power supply board. Due to the influence of variations in position detectors, etc., there is a risk that variations in the mounting position of the position detector with respect to the frame will increase. Further, if the mounting position of the position detector with respect to the frame fixed to the host device varies greatly, the origin position of the movable body may vary greatly when the linear drive device is mounted on the host device.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a linear drive device having a position detection mechanism for detecting the position of a movable body in the axial direction of a feed screw shaft, in which a motor frame is fixed to a host device on which the linear drive device is mounted. It is an object of the present invention to provide a linear drive device capable of suppressing variations in the attachment position of a detector body of a position detection mechanism relative to a position detection mechanism.

In order to solve the above-described problems, the linear driving device of the present invention is a linear driving device for rotating a feed screw shaft to linearly move a movable body. and a position detection mechanism for detecting the position of the movable body in the axial direction of the feed screw shaft. The position detection mechanism comprises a rotor, a stator, and a frame fixed to a host device on which the linear drive device is mounted and to which the stator is fixed. The detector body is formed with positioning projections for positioning the detector body with respect to the frame, and the frame is formed with positioning holes into which the positioning projections are inserted. Characterized by

In the linear drive device of the present invention, the position detection mechanism for detecting the position of the movable body in the axial direction of the feed screw shaft has a detector body, and the motor is fixed to the host device on which the linear drive device is mounted. It has a frame that holds Further, in this embodiment, the detector main body is formed with positioning projections for positioning the detector main body with respect to the frame, and the frame is formed with positioning holes into which the positioning projections are inserted. As such, the present invention allows positioning of the detector body directly with respect to the frame. Therefore, according to the present invention, it is possible to suppress variations in the attachment position of the detector main body with respect to the frame fixed to the host device.

In the present invention, for example, a first positioning projection and a second positioning projection are formed as positioning projections in the detector main body, and the first positioning projection is inserted as a positioning hole in the frame. and a second positioning hole into which the second positioning projection is inserted. The detector body is positioned by the second positioning projection and the second positioning hole in the rotation direction of the detector body with the first positioning projection as the center of rotation. ing.

In the present invention, the substrate is formed with a press-fitting hole that penetrates the substrate and into which the positioning projection is press-fitted. It is preferable that the tip of the protrusion is inserted. With this configuration, it is possible to fix the detector body to the substrate using the positioning protrusions for positioning the detector body with respect to the frame. Therefore, it is possible to simplify the configuration of the position detection mechanism as compared with the case where the configuration for fixing the detector main body to the substrate is provided separately.

In the present invention, the linear drive device includes a fixing screw for fixing the substrate to the frame, the substrate is formed with a screw through hole through which the shaft portion of the fixing screw is inserted, and the frame is provided with the fixing screw. Preferably, a threaded hole is formed in which the shank engages. With this configuration, the detector body, which is press-fitted and fixed to the substrate, can be fixed to the frame together with the substrate by means of the fixing screws, so the position detection mechanism can be attached to the frame with a relatively simple configuration. become.

In the present invention, for example, a predetermined direction perpendicular to the axial direction of the feed screw shaft is the first direction, one axial side of the feed screw shaft is the output side, and the other axial side of the feed screw shaft is the counter-output side. , one side in the first direction is the second direction side, and the other side in the first direction is the third direction side. comprises a flat plate-shaped bottom portion constituting the third direction side portion of the frame, a bearing holding portion that rises from the output side portion of the bottom portion toward the second direction side and holds the output side bearing, and an opposite side of the bottom portion. a fixed portion that rises from the output side portion toward the second direction side and to which the stator is fixed; the thickness direction of the bottom portion coincides with the first direction; and the movable body is the axis of the feed screw shaft The position detection mechanism is mounted on the output side portion of the bottom surface, which is the surface of the bottom surface portion on the third direction side, and detects the position of the movable body on the output side. .

In the present invention, for example, the substrate is arranged so that the thickness direction of the substrate is aligned with the first direction, and is fixed to the bottom surface portion on the third direction side. and a solder land to which the tip of the terminal pin is soldered are formed, the terminal pin is inserted through the terminal through hole from the third direction side, and the solder land is for the terminal A bottom through-hole is formed at the edge of the through-hole and is formed on the surface of the substrate on the second direction side. A hole is formed.

In this case, even when the substrate is fixed to the bottom surface, the terminal pins of the detector body and the solder lands of the substrate can be soldered from the second direction side of the bottom surface using the through holes of the bottom surface. becomes possible to do. Further, in this case, even if the surface of the substrate on the second direction side is in contact with the bottom surface of the bottom surface portion, interference between the soldered portions of the terminal pins of the detector main body and the solder lands of the substrate and the bottom surface portion is prevented. it becomes possible to

In the present invention, for example, the movable body has a detected portion that is detected by the position detection mechanism, the detected portion projects toward the third direction, and the third direction end of the detected portion extends from the bottom portion. If the direction perpendicular to the axial direction of the feed screw shaft and the first direction is defined as the fourth direction, the movable body moves in the axial direction of the feed screw shaft on the bottom surface. A passage groove through which a portion of the detected portion sometimes passes and a straight groove extending from the passage groove to one side in the fourth direction are formed.

In this case, when assembling the linear drive device, a portion of the detected portion, the end of which is arranged in the third direction with respect to the bottom surface of the bottom portion, is arranged in the passage groove using the straight groove. becomes possible. Therefore, when assembling the linear drive device, even if a portion of the detected portion cannot be placed in the passage groove by moving the detected portion toward the passage groove in the third direction, It becomes possible to arrange a part in the passage groove.

In the present invention, for example, the movable body has a rotation prevention projection for preventing rotation of the movable body about the feed screw shaft, and the rotation prevention projection is located on the second direction side of the bottom portion. The anti-rotation projections arranged on both sides of the passage groove in the fourth direction and arranged on one side in the fourth direction are fitted in the straight grooves throughout the movable range of the movable body. It is possible to contact the surface of the bottom surface portion on the second direction side without any contact. In this case, even if the movable body has the anti-rotation projection and the linear groove is formed on the bottom surface, the anti-rotation projection does not fit into the linear groove. does not interfere with the movement of the movable body.

As described above, according to the present invention, in a linear driving device provided with a position detection mechanism for detecting the position of a movable body in the axial direction of a feed screw shaft, a motor fixed to a host device on which the linear driving device is mounted is provided. It is possible to suppress variations in the attachment position of the detector body of the position detection mechanism with respect to the frame.

1 is a side view of a linear drive device according to an embodiment of the invention; FIG. FIG. 2 is a cross-sectional view for explaining the configuration of the EE cross section of FIG. 1; 2 is a bottom view of the linear drive shown in FIG. 1; FIG. Figure 2 is a plan view of a portion of the linear drive shown in Figure 1; FIG. 2 is a plan view of the position detection mechanism shown in FIG. 1; FIG. 8 is a plan view for explaining the structure of a frame according to another embodiment of the invention;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Overall Configuration of Linear Drive Device)
FIG. 1 is a side view of a linear drive device 1 according to an embodiment of the invention. FIG. 2 is a cross-sectional view for explaining the structure of the EE cross section of FIG. FIG. 3 is a bottom view of the linear drive device 1 shown in FIG. FIG. 4 is a plan view of part of the linear drive 1 shown in FIG.

A linear drive device 1 of this embodiment includes a motor 2 and a movable body 3 that is linearly moved by the power of the motor 2 . The linear drive device 1 is used by being mounted on a predetermined host device (not shown). When the movable body 3 moves, the host device performs a predetermined operation. Motor 2 is a stepping motor. The motor 2 includes a rotor 6 having a rotating shaft 4 and driving magnets 5 , and a stator 8 having driving coils 7 and arranged on the outer peripheral side of the driving magnets 5 . An output-side portion of the rotating shaft 4 protrudes further toward the output side than the stator 8 . A portion of the rotary shaft 4 protruding from the stator 8 is a feed screw shaft (lead screw) 4a having a feed screw formed on the outer peripheral surface thereof.

The movable body 3 engages with the feed screw shaft 4a and moves linearly in the axial direction of the feed screw shaft 4a when the feed screw shaft 4a rotates. That is, the linear drive device 1 rotates the feed screw shaft 4a to move the movable body 3 linearly. The linear drive device 1 includes a position detection mechanism 9 for detecting the position of the movable body 3 in the axial direction of the feed screw shaft 4a, two lead wires 10 drawn out from the position detection mechanism 9, and two lead wires. and a holder 11 for defining the routing position of 10 . 1, illustration of the lead wire 10 is omitted.

In the following description, the X direction in FIG. 1, etc., which is the axial direction of the rotating shaft 4 (that is, the axial direction of the feed screw shaft 4a) is defined as the front-rear direction, and the X1 direction in FIG. Let the "front" side be the "front" side, and let the X2 direction side in FIG. Further, hereinafter, for convenience of explanation, the Y direction in FIG. 1 etc. orthogonal to the front-rear direction is defined as the horizontal direction, and the Z direction in FIG. 1 etc. orthogonal to the front-rear direction and the horizontal direction is defined as the vertical direction. In addition, the Y1 direction side in FIG. 2 etc., which is one side in the horizontal direction, is the “right” side, the Y2 direction side in FIG. 2 etc., which is the other side in the horizontal direction is the “left” side, and The Z1 direction side of a certain figure such as FIG. 1 is defined as the "upper" side, and the Z2 direction side of FIG.

The front side (X1 direction side) of this embodiment is the output side, which is one side in the axial direction of the feed screw shaft 4a, and the rear side (X2 direction side) is the other side in the axial direction of the feed screw shaft 4a. There is an anti-output side. In addition, the vertical direction (Z direction) of this embodiment is a first direction that is a predetermined direction orthogonal to the axial direction of the feed screw shaft 4a, and the horizontal direction (Y direction) is the axis of the feed screw shaft 4a. The fourth direction is a direction orthogonal to the direction and the first direction. The upper side (Z1 direction side) is the second direction side, which is one side of the first direction, and the lower side (Z2 direction side) is the third direction side, which is the other side of the first direction. ing.

In addition to the rotor 6 and the stator 8, the motor 2 includes a frame 14 to which the stator 8 is fixed, an output-side bearing 16 that supports the front portion of the rotating shaft 4 (that is, the output-side portion of the feed screw shaft 4a), It has a non-output side bearing 17 that supports the rear portion of the rotating shaft 4, and a plate spring 18 that contacts the rear end of the rotating shaft 4 and biases the rotating shaft 4 forward. 3, the motor 2 includes terminal pins 19 to which the ends of the drive coils 7 are electrically connected, a substrate 20 to which the terminal pins 19 are fixed, and a substrate holder that holds the substrate 20. As shown in FIG. 21 and lead wires 22 drawn out from the substrate 20 . 2, illustration of the leaf spring 18, the substrate 20, the substrate holder 21, and the lead wire 22 is omitted.

As shown in FIG. 2 , the rotor 6 has a boss 24 fixed to the rear end portion of the rotating shaft 4 . Boss 24 is formed in a thick cylindrical shape, for example, and is fixed to the outer peripheral surface of rotating shaft 4 . The driving magnet 5 is formed in a cylindrical shape. The drive magnet 5 is fixed to the outer peripheral surface of the boss 24 . The drive magnet 5 is arranged behind the feed screw shaft 4a. The drive magnet 5 rotates together with the feed screw shaft 4a.

The stator 8 is formed in a substantially cylindrical shape as a whole. A front end surface and a rear end surface of the stator 8 are annular planes perpendicular to the front-rear direction. The stator 8 is arranged between the drive coil 7 and the stator core 25 formed with a plurality of pole teeth facing the outer peripheral surface of the drive magnet 5 and between the stator core 25 and the drive coil 7 . A bobbin 26 is provided. The drive coil 7 is wound around a bobbin 26 . The driving coil 7 is arranged on the outer peripheral side of the plurality of pole teeth via the bobbin 26 . The stator 8 also includes a flat plate-like end plate 29 fixed to the front surface of the stator core 25 and a flat plate-like end plate 30 fixed to the rear surface of the stator core 25 .

One end of the terminal pin 19 is fixed to a terminal holding portion formed on the bobbin 26 . The terminal pin 19 protrudes leftward. The substrate holder 21 is fixed to the left end of the stator core 25 . The substrate 20 is a flat rigid substrate such as a glass epoxy substrate. The substrate 20 held by the substrate holder 21 is arranged such that the thickness direction of the substrate 20 is aligned with the left-right direction. The other end of the terminal pin 19 is soldered and fixed to the board 20 . One end of the lead wire 22 is soldered and fixed to the substrate 20 . The lead wire 22 is routed from the substrate 20 toward the rear side.

The frame 14 is fixed to a host device on which the linear drive device 1 is mounted. The frame 14 has a flat plate-shaped bottom portion 14a forming the lower portion of the frame 14 . The bottom portion 14a is arranged so that the thickness direction of the bottom portion 14a is aligned with the vertical direction. That is, the thickness direction of the bottom portion 14a matches the vertical direction. The frame 14 also includes a flat plate-like side portion 14b rising upward from the front portion of the bottom portion 14a, and a flat plate-like side portion 14c rising upward from the rear portion of the bottom portion 14a. . The side portion 14b rises at a right angle from the front end of the bottom portion 14a, and the side portion 14c rises at a right angle from the rear end of the bottom portion 14a.

The frame 14 is composed of a bottom portion 14a and two side portions 14b and 14c, and is formed in the shape of an angular groove. The side portion 14 b holds the output side bearing 16 . The stator 8 is fixed to the side portion 14c. The front end surface of the stator 8 (specifically, the front surface of the end plate 29) is fixed to the side surface portion 14c. A through hole through which the rotating shaft 4 is inserted is formed in the side surface portion 14c. The side surface portion 14 b of this embodiment serves as a bearing holding portion that holds the output side bearing 16 . Moreover, the side surface portion 14c serves as a fixed portion to which the stator 8 is fixed.

A guide shaft 27 that guides the movable body 3 in the front-rear direction is fixed to the frame 14 . A front end portion of the guide shaft 27 is fixed to the side portion 14b, and a rear end portion of the guide shaft 27 is fixed to the side portion 14c. As mentioned above, the frame 14 is fixed to the host device on which the linear drive 1 is mounted. Specifically, the bottom portion 14a is fixed to the host device. A fixing hole (not shown) for fixing the frame 14 to a host device is formed in the bottom surface portion 14a. This fixing hole penetrates the bottom surface portion 14a in the vertical direction. The frame 14 is fixed to the host device by screws inserted through the fixing holes, for example.

The bottom surface portion 14a has a passage groove 14d through which a portion of a detected portion 28b (to be described later) that constitutes a part of the movable body 3 passes when the movable body 3 moves in the front-rear direction. A linear groove 14e to be used is formed. The passage groove 14d and the straight groove 14e penetrate the bottom surface portion 14a in the vertical direction. The passage groove 14d is formed in a rectangular shape elongated in the front-rear direction. 14 d of passage grooves are formed in the center position of the bottom face part 14a in the left-right direction. The straight groove 14e is formed in a rectangular shape elongated in the left-right direction. One end of the straight groove 14e is connected to the passage groove 14d, and the straight groove 14e extends to one side in the left-right direction from the passage groove 14d. Specifically, the straight groove 14e extends rightward from the passage groove 14d. The straight groove 14e is formed behind the central position of the bottom surface portion 14a in the front-rear direction.

In this embodiment, when a detected portion 28b, which will be described later, contacts the rear end surface of the passage groove 14d, the rearward movement of the movable body 3 is restricted. That is, in this embodiment, the state in which the detected portion 28b is in contact with the rear end surface of the passage groove 14d is the state in which the movable body 3 has moved to the rear end of the movable range (movable range in the front-rear direction) of the movable body 3. It's becoming

As shown in FIG. 4, the front portion of the bottom portion 14a is provided with a work through hole 14f for use in soldering and fixing the lead wire 10 to a substrate 34 (to be described later) that constitutes the position detection mechanism 9. , and through holes 14g and 14h for positioning the position detection mechanism 9 are formed. Two screw holes 14p are formed in the front portion of the bottom surface portion 14a for fixing a substrate 34, which will be described later, to the bottom surface portion 14a. A through hole 14i for fixing the holder 11 and through holes 14j and 14k for positioning the holder 11 are formed in the rear portion of the bottom surface portion 14a. The through holes 14f to 14k and the screw hole 14p pass vertically through the bottom portion 14a.

The through hole 14f is formed in the front end portion of the bottom portion 14a. The through hole 14f is formed in a rectangular shape elongated in the left-right direction. The through holes 14g and 14h are formed behind the through hole 14f. The through hole 14g is a round hole. The through hole 14h is an elongated hole whose longitudinal direction is the left-right direction. The through hole 14g and the through hole 14h are formed at the same position in the front-rear direction. Further, the through hole 14g and the through hole 14h are arranged so as to be adjacent to each other in the left-right direction. The two screw holes 14p are formed behind the through holes 14g and 14h. The two screw holes 14p are formed at the same position in the front-rear direction. In addition, the two screw holes 14p are arranged outside the through holes 14g and 14h in the left-right direction. Also, the two screw holes 14p are arranged on the front side of the passage groove 14d.

The through holes 14i to 14k are formed in the rear end portion of the bottom portion 14a. The through hole 14i is formed in a rectangular shape whose long side direction is the front-rear direction. The through-holes 14i are formed at two locations on both ends in the left-right direction of the bottom surface portion 14a. The through hole 14j is a round hole. The through hole 14k is an elongated hole whose longitudinal direction is the left-right direction. The through hole 14g and the through hole 14h are formed at the same position in the front-rear direction. Further, the through holes 14g and 14h are arranged with a space therebetween in the left-right direction. The through holes 14g and 14h are arranged between the two through holes 14i in the left-right direction. The through holes 14i to 14k are arranged behind the passage groove 14d.

As described above, the output side bearing 16 is held by the side surface portion 14b. The output-side bearing 16 supports the front end of the rotating shaft 4 (that is, the front end of the feed screw shaft 4a). Further, the output-side bearing 16 supports the rotating shaft 4 in the axial direction (front-rear direction) of the rotating shaft 4 and in the radial direction of the rotating shaft 4 . The anti-output side bearing 17 is held by the end plate 30 . The anti-output side bearing 17 supports the rear end of the rotating shaft 4 . Further, the non-output side bearing 17 supports the rotating shaft 4 in the radial direction of the rotating shaft 4 . The leaf spring 18 is fixed to the rear surface of the end plate 30 .

The movable body 3 is arranged between the side portion 14b and the side portion 14c in the front-rear direction. The movable body 3 includes a nut member (not shown) formed with a screw hole that engages with the feed screw shaft 4a, and a slider 28 that moves linearly in the front-rear direction together with the nut member. The slider 28 is formed with a guide hole (not shown) through which the guide shaft 27 is inserted and a nut placement recess (not shown) in which a nut member is placed. The slider 28 has a rotation prevention projection 28a for preventing rotation of the slider 28 about the feed screw shaft 4a (see FIGS. 1 and 4). That is, the movable body 3 is provided with a rotation prevention protrusion 28a for preventing rotation of the movable body 3 about the feed screw shaft 4a.

The anti-rotation protrusion 28a protrudes downward from the front end of the slider 28. As shown in FIG. The anti-rotation protrusion 28a is arranged on the upper side of the bottom surface portion 14a. The anti-rotation protrusions 28a are formed at both ends of the slider 28 in the left-right direction, and are arranged on both sides of the passage groove 14d in the left-right direction (see FIG. 4). Of the two rotation prevention projections 28a, the rotation prevention projection 28a arranged on the right side (that is, of the two rotation prevention projections 28a, arranged on the side where the straight groove 14e is formed). The anti-rotation projection 28a (the anti-rotation projection 28a arranged on one side in the left-right direction) is arranged on the left side of the right end of the straight groove 14e.

The anti-rotation projection 28a can contact the upper surface of the bottom surface portion 14a without being fitted in the linear groove 14e throughout the movable range of the movable body 3. As shown in FIG. That is, the linear groove 14e is formed at a position where the anti-rotation projection 28a does not fit into the linear groove 14e throughout the movable range of the movable body 3. As shown in FIG. In this embodiment, when the movable body 3 moves to the rear end of the movable range (movable range in the front-rear direction) of the movable body 3, the rear end portion of the anti-rotation protrusion 28a reaches the upper side of the linear groove 14e. (See the two-dot chain line in FIG. 4), even if the movable body 3 moves to the rear end of the movable range of the movable body 3, the anti-rotation projection 28a does not fit into the straight groove 14e. Of the two rotation prevention projections 28a, the left rotation prevention projection 28 can contact the upper surface of the bottom surface portion 14a over the entire movable range of the movable body 3. As shown in FIG.

The slider 28 also has a detected portion 28b that is detected by the position detection mechanism 9. As shown in FIG. That is, the movable body 3 has a detected portion 28b that is detected by the position detection mechanism 9. As shown in FIG. The detected portion 28b protrudes downward at the rear end portion of the slider 28 . The lower end of the detected portion 28b is arranged below the bottom surface 14r, which is the lower surface of the bottom surface portion 14a. A portion of the detected portion 28b is arranged in the passage groove 14d. The detected portion 28b is formed in a substantially rectangular flat plate shape elongated in the vertical direction. The detected portion 28b is arranged so that the thickness direction of the detected portion 28b coincides with the front-rear direction.

When assembling the linear drive device 1, the rotor 6 and the stator 8 are assembled, the driving magnet 5 is arranged on the inner peripheral side of the stator 8, and the nut member of the movable body 3 is attached to the feed screw shaft 4a. Then, the stator 8 is fixed to the frame 14 and both ends of the rotary shaft 4 are supported by the output side bearing 16 and the anti-output side bearing 17 . After that, the slider 28 is assembled to the nut member by moving the slider 28 from the right side of the frame 14 to the left side and arranging the nut member in the nut arrangement concave portion of the slider 28 .

When the slider 28 is moved from the right side of the frame 14 to the left side, part of the detected portion 28b is arranged in the straight groove 14e. That is, when moving the slider 28 from the right side of the frame 14 to the left side, the straight groove 14e is used to move the detected portion 28b to the left side, and a part of the detected portion 28b is arranged in the passage groove 14d. After that, the guide shaft 27 is inserted through the guide hole of the slider 28 and fixed to the frame 14 .

(Configuration of position detection mechanism and routing of lead wires)
5 is a plan view of the position detection mechanism 9 shown in FIG. 1. FIG.

The position detection mechanism 9 is attached to the front portion of the bottom surface 14r of the bottom surface portion 14a. The position detection mechanism 9 is arranged on the front side of the detected portion 28b, and detects the position of the movable body 3 on the front side. Specifically, the position detection mechanism 9 detects the origin position of the movable body 3 in the front-rear direction on the front side. The position detection mechanism 9 is a contact switch. The position detection mechanism 9 includes a detector body 32 and a board 34 to which the detector body 32 is electrically connected. Terminal pins 33 of the detector main body 32 are connected to the board 34 . The detector body 32 has two terminal pins 33 . The detector main body 32 and the substrate 34 are arranged below the bottom surface 14r of the bottom surface portion 14a.

The detector main body 32 has a contact portion 35 movable in the front-rear direction. The contact portion 35 protrudes rearward and is biased rearward. When the detected portion 28b of the movable body 3 comes into contact with the contact portion 35 and the contact portion 35 moves forward to a predetermined position, it is detected that the movable body 3 is at the origin position. The terminal pin 33 is arranged on the front side of the detector main body 32 . The terminal pin 33 is formed in an L shape extending forward from the detector main body 32 and then upward. The two terminal pins 33 are arranged adjacent to each other in the left-right direction.

Positioning protrusions 32 a and 32 b for positioning the detector body 32 with respect to the frame 14 are formed on the detector body 32 . Specifically, the detector main body 32 is formed with positioning protrusions 32a and 32b for positioning the detector main body 32 with respect to the frame 14 in a direction perpendicular to the vertical direction. The positioning protrusions 32a and 32b protrude upward. The positioning projections 32a and the positioning projections 32b are arranged adjacent to each other in the left-right direction. The positioning projection 32a is formed in a cylindrical shape with a circular cross section. The positioning projection 32b is formed in an elliptical columnar shape with an elliptical cross-sectional shape.

The substrate 34 is a flat rigid substrate such as a glass epoxy substrate. The substrate 34 is arranged so that the thickness direction of the substrate 34 is aligned with the vertical direction. The substrate 34 is fixed to the lower side of the bottom surface portion 14a. The upper surface of the substrate 34 is in contact with the bottom surface 14r of the bottom surface portion 14a. The substrate 34 is fixed to the front portion of the bottom portion 14a by two fixing screws 36. As shown in FIG. The detector body 32 is fixed to the substrate 34 . The upper surface of the detector body 32 is in contact with the lower surface of the substrate 34 .

As shown in FIG. 5, the substrate 34 is formed with through holes 34e and 34f penetrating the substrate 34 in the vertical direction. Further, the substrate 34 is formed with two through holes 34g penetrating the substrate 34 in the vertical direction. The through hole 34e is a round hole. The through hole 34f is an elongated hole whose longitudinal direction is the left-right direction. The through holes 34e and 34f are formed in the central portion of the substrate 34 in the front-rear direction. The through hole 34e and the through hole 34f are formed at the same position in the front-rear direction. Further, the through holes 34e and 34f are arranged with a space therebetween in the left-right direction. The through hole 34g is a round hole. The two through holes 34g are formed at the same position in the front-rear direction. The two through-holes 34g are arranged behind the through-holes 34e and 34f and outside the through-holes 34e and 34f in the left-right direction.

A positioning protrusion 32a is press-fitted into the through hole 34e. A positioning protrusion 32b is press-fitted into the through hole 34f. The detector main body 32 is fixed to the substrate 34 by press-fitting the positioning protrusions 32a and 32b into the through holes 34e and 34f. That is, the detector main body 32 is press-fitted and fixed to the substrate 34 . The tips of the positioning protrusions 32 a and 32 b protrude from the substrate 34 . Specifically, the tip portions of the positioning protrusions 32 a and 32 b protrude upward from the upper surface of the substrate 34 . The through holes 34e and 34f of this embodiment are press-fit holes into which the positioning protrusions 32a and 32b are press-fitted.

The tip of the positioning projection 32a projecting from the upper surface of the substrate 34 is inserted into the through hole 14g, and the tip of the positioning projection 32b projecting from the upper surface of the substrate 34 is inserted into the through hole 14h. That is, the positioning projection 32a is inserted into the through hole 14g, and the positioning projection 32b is inserted into the through hole 14h. Specifically, the tip of the positioning protrusion 32a protruding from the upper surface of the substrate 34 is press-fitted into the through hole 14g, and the tip of the positioning protrusion 32b protruding from the upper surface of the substrate 34 is press-fitted into the through hole 14h. ing.

In this embodiment, the detector main body 32 is positioned with respect to the frame 14 by the positioning projections 32a, 32b and the through holes 14g, 14h into which the positioning projections 32a, 32b are press-fitted. Further, in this embodiment, the positioning projection 32b and the through hole 14h position the detector body 32 in the rotation direction of the detector body 32 with the positioning projection 32a as the center of rotation. The positioning projection 32a of this embodiment is a first positioning projection, and the positioning projection 32b is a second positioning projection. Further, the through holes 14g and 14h of this embodiment are positioning holes into which the positioning protrusions 32a and 32b are inserted. The through hole 14g is a first positioning hole, and the through hole 14h is a second positioning hole.

The shaft portion of the fixing screw 36 is inserted through the through hole 34g from below and engaged with the screw hole 14p. The head of the fixing screw 36 is arranged below the substrate 34 . Two fixing screws 36 are arranged so as to sandwich the detector main body 32 in the left-right direction, one fixing screw 36 is arranged on the right side of the detector main body 32, and the other fixing screw 36 is arranged on the right side of the detector main body 32. , are arranged on the left side of the detector body 32 . 34 g of through-holes of this form are through-holes for screws.

The substrate 34 has two through holes 34a through which the terminal pins 33 are inserted, two through holes 34b through which the core wires of one end of the lead wires 10 are inserted, and the tips of the terminal pins 33 are soldered. Two solder lands 34c to be attached and two solder lands 34d to which the core wire of the lead wire 10 is soldered are formed. The through hole 34a of this embodiment is a terminal through hole. 4, illustration of the terminal pin 33 and the core wire of the lead wire 10 is omitted. 5, illustration of the terminal pin 33 is omitted.

Through holes 34 a , 34 b and solder lands 34 c , 34 d are formed at the front end of substrate 34 . The through holes 34 a , 34 b and solder lands 34 c , 34 d are arranged on the front side of the detector main body 32 . The through holes 34a and 34b are round holes that penetrate the substrate 34 in the vertical direction. The terminal pin 33 is inserted from below into the through hole 34a, and the core wire of the lead wire 10 is inserted from below into the through hole 34b.

The through holes 34a and 34b are formed at the same positions in the front-rear direction. The two through holes 34a are spaced apart in the left-right direction, and the two through holes 34b are spaced apart in the left-right direction. The two through holes 34a are arranged inside the two through holes 34b in the left-right direction. Solder lands 34 c and 34 d are formed on the upper surface of substrate 34 . The solder land 34c is formed at the edge of the through hole 34a, and the solder land 34d is formed at the edge of the through hole 34b.

When viewed from above the bottom surface portion 14a, the front end portion of the substrate 34 is arranged in the through hole 14f of the bottom surface portion 14a, and the through holes 34a, 34b and the solder lands 34c, 34d are located in the through hole 14f. placed inside. That is, a through hole 14f is formed in the bottom portion 14a above the through holes 34a, 34b and the solder lands 34c, 34d. In this embodiment, the through holes 14f are used to solder the terminal pins 33 to the solder lands 34c from above the bottom surface portion 14a. Also, using the through hole 14f, the core wire of the lead wire 10 is soldered to the solder land 34d from the upper side of the bottom surface portion 14a. The through hole 14f of this embodiment is a bottom through hole.

The lead wire 10 drawn out from the substrate 34 is routed rearward along the bottom surface 14r of the bottom surface portion 14a (see FIG. 3). One lead wire 10 of the two lead wires 10 is routed on the right side of the passage groove 14d, and the other lead wire 10 is routed on the left side of the passage groove 14d. The lead wire 10 is connected to the connector 37 on the rear side of the stator 8 together with the lead wire 22 led out from the substrate 20 .

(Holder configuration)
The holder 11 is provided to define the routing position of the two lead wires 10 that are routed rearward along the bottom surface 14r of the bottom surface portion 14a. The holder 11 is made of resin. The holder 11 is fixed to the rear end portion of the bottom portion 14a. The holder 11 is arranged behind the movable body 3 when the movable body 3 has moved to the rear end of the movable range (movable range in the front-rear direction) of the movable body 3 . The holder 11 has a main body portion 11a formed in a rectangular parallelepiped shape elongated in the left-right direction, and two positioning projections 11b (see FIG. 4) for positioning the holder 11 with respect to the bottom surface portion 14a in a direction perpendicular to the vertical direction. ) and two engaging projections 11c that engage with the bottom surface portion 14a.

The body portion 11a is arranged below the bottom portion 14a. Lead wire restricting portions 11d are formed at both ends of the main body portion 11a in the left-right direction (see FIG. 3). placed in between. A recess in which a part of the lead wire 10 is arranged is formed in the lead wire restricting portion 11d. The positioning projection 11b is formed in a cylindrical shape rising upward from the main body portion 11a. The two positioning projections 11b are arranged at the same position in the front-rear direction and are arranged in a state of being spaced apart in the left-right direction. The positioning projections 11b are inserted into the through holes 14j and 14k from below.

The engaging projections 11c rise upward from both ends of the body portion 11a in the left-right direction. The engaging projection 11c is formed in a flat plate shape having a thickness direction in the left-right direction as a whole, and is elastically deformable in the left-right direction. The engaging protrusion 11c is arranged in the through hole 14i. The upper end portion of the engaging projection 11c is a claw portion formed with a contact surface that contacts the upper surface of the bottom surface portion 14a inside the through hole 14i in the left-right direction. In this embodiment, the holder 11 is fixed to the bottom portion 14a by snap-fitting using the elasticity of the engaging projections 11c. When fixing the holder 11 to the bottom surface portion 14a, the claw portion of the engaging projection 11c passes through the through hole 14i from the bottom to the top.

(Main effects of this form)
As described above, in the linear drive device 1 of this embodiment, the positioning projections 32a and 32b for positioning the detector main body 32 with respect to the frame 14 fixed to the host device on which the linear drive device 1 is mounted are provided. The frame 14 is formed with through holes 14g and 14h formed in the detector main body 32 and into which the positioning projections 32a and 32b are inserted. That is, in this embodiment, the detector main body 32 is positioned directly with respect to the frame 14 . Therefore, in this embodiment, it is possible to suppress variation in the mounting position of the detector main body 32 with respect to the frame 14 fixed to the host device. In addition, in this embodiment, through holes 14g and 14h are formed in the bottom portion 14a in which the fixing holes for fixing the frame 14 to the host device are formed. can be effectively suppressed.

In this embodiment, the detector main body 32 is fixed to the substrate 34 by press-fitting the positioning projections 32a and 32b into the through holes 34e and 34f of the substrate 34 . That is, in this embodiment, the detector main body 32 is fixed to the substrate 34 using the positioning projections 32 a and 32 b for positioning the detector main body 32 with respect to the frame 14 . Therefore, in this embodiment, the configuration of the position detection mechanism 9 can be simplified compared to the case where a configuration for fixing the detector main body 32 to the substrate 34 is provided separately. In addition, in this embodiment, the detector body 32 press-fitted and fixed to the substrate 34 is fixed to the frame 14 together with the substrate 34 by the fixing screws 36. Therefore, the position detection mechanism 9 can be mounted on the frame 14 with a relatively simple structure. 14 can be attached.

In this embodiment, the solder lands 34c and 34d are arranged in the through holes 14f when viewed from above the bottom surface portion 14a. In addition, in this embodiment, the terminal pin 33 is soldered to the solder land 34c from the upper side of the bottom surface portion 14a by using the through hole 14f, and the core wire of the lead wire 10 is connected to the solder land 34d from the upper side of the bottom surface portion 14a. It is soldered. Therefore, in this embodiment, even when the substrate 34 is fixed to the bottom surface portion 14a, the terminal pins 33 and the core wires of the lead wires 10 can be easily soldered from above the bottom surface portion 14a using the through holes 14f. becomes possible.

In this embodiment, when viewed from above the bottom surface portion 14a, the solder lands 34c and 34d are arranged in the through holes 14f, so that the top surface of the board 34 is in contact with the bottom surface 14r of the bottom surface portion 14a. Even so, it is possible to prevent interference between the soldered portion of the terminal pin 33 and the solder land 34c and the bottom portion 14a, and the soldered portion of the core wire of the lead wire 10 and the solder land 34d and the bottom portion 14a. It is possible to prevent interference with

In this embodiment, a straight groove 14e extending rightward from the passage groove 14d is formed in the bottom surface portion 14a. When the linear drive device 1 is assembled, the straight groove 14e is used to move the detected portion 28b leftward. A portion of the detected portion 28b is arranged in the passage groove 14d. Therefore, in the present embodiment, when assembling the linear drive device 1, the detected portion 28b whose lower end is arranged below the bottom surface 14r of the bottom surface portion 14a is moved downward toward the passage groove 14d. Even if part of the portion 28b cannot be placed in the passage groove 14d, part of the detected portion 28b can be placed in the passage groove 14d.

In this embodiment, the anti-rotation protrusion 28a of the slider 28 can contact the upper surface of the bottom surface portion 14a without being fitted into the linear groove 14e throughout the movable range of the movable body 3. As shown in FIG. That is, in this embodiment, even if the slider 28 has the anti-rotation projection 28a and the linear groove 14e is formed in the bottom surface portion 14a, the anti-rotation projection 28a does not fit into the linear groove 14e. Therefore, in this embodiment, the anti-rotation projection 28a and the linear groove 14e do not interfere with the movement of the movable body 3. As shown in FIG.

(Other embodiments)
The embodiment described above is an example of the preferred embodiment of the present invention, but the present invention is not limited to this, and various modifications can be made without departing from the gist of the present invention.

In the embodiment described above, as shown in FIG. 6, a pair of through holes 14g and 14h arranged at the same position in the front-rear direction are formed at two locations spaced apart from each other in the front-rear direction. A pair of screw holes 14p arranged at positions may be formed at two locations with an interval therebetween in the front-rear direction. In addition, a pair of through holes 14g and 14h arranged at the same position in the front-rear direction are formed at three or more locations spaced apart in the front-rear direction, and a pair of screw holes arranged at the same position in the front-rear direction. 14p may be formed at three or more locations spaced apart in the front-rear direction.

The width of the through-hole 14f in this case in the front-rear direction is wider than the width in the front-rear direction of the through-hole 14f in the above-described embodiment. In this case, it is possible to easily change the mounting position of the position detection mechanism 9 in the front-rear direction with respect to the frame 14 . That is, in this case, it becomes possible to easily change the origin position of the movable body 3 .

In the embodiment described above, the position detection mechanism 9 may be arranged on the rear side of the movable body 3 to detect the origin position of the movable body 3 in the front-rear direction on the rear side. In this case, for example, the position detection mechanism 9 is attached to the rear portion of the bottom surface 14r of the bottom surface portion 14a. Further, in this case, the position detection mechanism 9 may be arranged on the upper end side of the side surface portion 14c, like the linear drive device described in Patent Document 1, for example. When the position detection mechanism 9 is arranged on the upper end side of the side surface portion 14c, for example, an attachment portion to which the position detection mechanism 9 is attached is formed so as to be connected to the upper end portion of the side surface portion 14c. are formed with positioning holes into which the positioning protrusions 32a and 32b are inserted.

In the embodiment described above, the positioning holes into which the positioning projections 32a and 32b are inserted need not penetrate the bottom surface portion 14a. Moreover, in the above-described embodiment, the detector main body 32 may be fixed to the substrate 34 by fixing means such as screws. In this case, gaps are formed between the positioning protrusions 32a, 32b inserted through the through holes 34e, 34f and the through holes 34e, 34f. Furthermore, in the embodiment described above, when the linear drive device 1 is assembled, part of the detected portion 28b can be arranged in the passing groove 14d by moving the detected portion 28b downward toward the passage groove 14d. , the straight groove 14e may not be formed in the bottom surface portion 14a.

In the embodiment described above, the positioning projection 32b may be formed in a columnar shape, an elliptical columnar shape, or a polygonal columnar shape such as a triangular or square columnar shape. Further, in the above embodiment, a part of the rotary shaft 4 is the feed screw shaft 4a. Furthermore, in the embodiment described above, the motor 2 may be a motor other than a stepping motor.

REFERENCE SIGNS LIST 1 linear drive device 2 motor 3 movable body 4a feed screw shaft 6 rotor 8 stator 9 position detection mechanism 14 frame 14a bottom portion 14b side portion (bearing holding portion)
14c side part (fixed part)
14d passage groove 14e straight groove 14f through hole (bottom part through hole)
14g through hole (positioning hole, first positioning hole)
14h through hole (positioning hole, second positioning hole)
14p Screw hole 14r Bottom surface 16 Output side bearing 28a Anti-rotation projection 28b Detected part 32 Main body of detector 32a Positioning projection (first positioning projection)
32b positioning projection (second positioning projection)
33 terminal pin 34 substrate 34a through hole (through hole for terminal)
34c Solder land 34e, 34f Through holes (press-fit holes)
34g through hole (through hole for screws)
36 Fixing screw X Axial direction of feed screw shaft X1 Output side X2 Non-output side Y Fourth direction Z First direction Z1 Second direction side Z2 Third direction side

Claims (8)

In a linear drive device that rotates a feed screw shaft to linearly move a movable body,
a motor having the feed screw shaft; the movable body that engages with the feed screw shaft and moves linearly in the axial direction of the feed screw shaft when the feed screw shaft rotates; and the axial direction of the feed screw shaft. A position detection mechanism for detecting the position of the movable body in
The motor includes a rotor, a stator, and a frame fixed to a host device on which the linear drive device is mounted and to which the stator is fixed,
The position detection mechanism includes a detector body and a substrate to which the detector body is electrically connected,
The detector body is formed with a positioning projection for positioning the detector body with respect to the frame,
A linear driving device, wherein the frame is formed with a positioning hole into which the positioning projection is inserted. A first positioning projection and a second positioning projection are formed on the detector body as the positioning projection,
The frame is formed with, as the positioning holes, a first positioning hole into which the first positioning projection is inserted and a second positioning hole into which the second positioning projection is inserted,
The first positioning projection is formed in a cylindrical shape,
The first positioning hole is a round hole into which the first positioning projection is press-fitted,
The detector body is positioned by the second positioning projection and the second positioning hole in a rotation direction of the detector body about the first positioning projection as a center of rotation. 2. The linear drive of claim 1. The substrate is formed with a press-fitting hole that penetrates the substrate and into which the positioning projection is press-fitted,
a tip portion of the positioning projection protrudes from the substrate;
3. The linear drive device according to claim 1, wherein a tip portion of said positioning projection protruding from said substrate is inserted into said positioning hole. a fixing screw for fixing the substrate to the frame;
A through-hole for a screw through which the shaft portion of the fixing screw is inserted is formed in the substrate,
4. The linear drive device according to claim 3, wherein said frame is formed with a threaded hole in which the shaft of said fixing screw is engaged. A predetermined direction orthogonal to the axial direction of the feed screw shaft is defined as a first direction, one axial side of the feed screw shaft is defined as an output side, and the other axial side of the feed screw shaft is defined as a counter-output side, Assuming that one side in the first direction is the second direction side and the other side in the first direction is the third direction side,
the motor comprises an output-side bearing that supports an output-side portion of the feed screw shaft;
The frame includes a flat plate-shaped bottom portion forming a third direction side portion of the frame, and a bearing holding portion rising from an output side portion of the bottom portion toward the second direction side and holding the output side bearing. , a fixing portion that rises from the counter-output side portion of the bottom portion toward the second direction side and to which the stator is fixed,
The thickness direction of the bottom portion matches the first direction,
the movable body is disposed between the bearing holding portion and the fixed portion in the axial direction of the feed screw shaft;
5. The position detecting mechanism according to any one of claims 1 to 4, wherein the position detection mechanism is attached to an output side portion of the bottom surface, which is a surface on the third direction side of the bottom surface portion, and detects the position of the movable body on the output side. A linear drive device according to any one of the preceding claims. The substrate is arranged so that the thickness direction of the substrate and the first direction are aligned, and is fixed to the bottom surface portion on the third direction side,
The substrate is formed with a terminal through hole through which the terminal pin of the detector body is inserted, and a solder land to which the tip of the terminal pin is soldered,
The terminal pin is inserted through the terminal through hole from the third direction side,
The solder land is formed on the edge of the terminal through hole and formed on the surface of the substrate on the second direction side,
6. The linear drive device according to claim 5, wherein a bottom portion through hole penetrating through the bottom portion in the first direction is formed in a portion of the bottom portion on the second direction side of the solder land. . The movable body includes a detected part that is detected by the position detection mechanism,
The detected portion protrudes toward the third direction,
a third direction end of the detected portion is arranged on a third direction side of the bottom surface of the bottom surface portion;
Assuming that a direction orthogonal to the axial direction of the feed screw shaft and the first direction is a fourth direction,
The bottom surface portion includes a passage groove through which a part of the detected portion passes when the movable body moves in the axial direction of the feed screw shaft, and a straight groove extending from the passage groove in one side in the fourth direction. 7. A linear drive device according to claim 5 or 6, characterized in that . the movable body includes a rotation prevention protrusion for preventing rotation of the movable body about the feed screw shaft;
The anti-rotation protrusions are arranged on the second direction side of the bottom surface portion and arranged on both sides of the passage groove in the fourth direction,
The anti-rotation projection arranged on one side in the fourth direction can contact the surface of the bottom surface portion on the second direction side without being fitted in the linear groove throughout the movable range of the movable body. 8. A linear drive according to claim 7, wherein

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