JP5751155B2 - motor - Google Patents

Description

  The present invention relates to a motor used for adjusting the flow rate of a fluid such as a gas.

  In general, a stepping motor as disclosed in Patent Document 1 below is used for devices that require high positioning accuracy and a predetermined rotation angle. For example, as shown in FIG. 7, this stepping motor is attached to a flow path pipe t of gas or the like and used for adjusting the flow rate of gas.

  As shown in FIG. 6, the motor 100 includes a cylindrical stator 30 in a bottomed cylindrical casing 50, a rotor 20 rotatably accommodated in the stator 30 via a gap, and the rotor A lead screw 40 that is disposed on the same axis as the axis 20 and screwed into the inner peripheral surface 20a of the rotor 20 so as to extend forward and backward from the one end 20a of the rotor 20. In addition, a bearing case 5b is disposed on the opening 50a side of the casing 50, and a cylindrical pressing member 60 in which the bearing 80 and the tip 40a side of the lead screw 40 extend forward and backward in the bearing case 50b. Arranged and roughly configured.

  Here, the rotor 20 is constituted by a cylindrical rotor supporter 20d integrally provided with a rotor magnet 20e, and is rotatably supported by ball bearings 80 disposed on one end 20a side and the other end 20b side. Has been. A plurality of female screws 140a are screwed on the inner peripheral surface 20c of the rotor supporter 20d. Further, multiple male threads 140b are screwed on the outer peripheral surface 40c of the lead screw 40 on the base end 40b side.

  Then, a male screw 140b screwed to the outer peripheral surface 40c of the lead screw 40 is screwed to a female screw 140a screwed to the inner peripheral surface 20c of the rotor supporter 20d, and the lead screw 40 is coaxial with the axis of the rotor 20. It is arranged on the line. Further, the lead screw 40 is restricted from being accompanied by the rotation of the rotor 20, and is extended from the one end portion 20 a side of the rotor 20 by the rotation of the rotor 20 so as to freely advance and retract.

  Further, the pressing member 60 disposed in the bearing case 5b extends from the central portion of the lead screw 40 so as to be able to advance and retreat, and in order to preload the ball bearing 80 at a fixed position, a push washer 170 is provided. It is fixed by. A valve member 150 is integrally provided at the tip 40 a of the lead screw 40, and the lead screw 40 is advanced from the one end 2 a side of the rotor 2 between the valve member 150 and the pressing member 60. A return spring 160 that biases in the direction to be moved is interposed.

  Further, the outer peripheral surface of the rotor magnet 20e provided integrally with the rotor supporter 20d is magnetized so as to have different polarities alternately in the circumferential direction. Further, the stator 30 has a bobbin 30b made of synthetic resin integrally formed on the outer periphery of two pairs of field plates 30a, and a coil 30c is wound around the outer periphery of the bobbin 30b. A plurality of pole teeth 30d are alternately arranged at equal intervals on the inner peripheral surface.

  In this conventional motor 100, when the step signal is input to the coil 30c of the pole teeth 30d of the field plate 30a, the pole teeth 30d become the N pole and the S pole, and a rotating magnetic field is generated. Since the N and S poles are alternately magnetized in the rotor magnet 20e, the rotation of the rotor 20 is continued in synchronization with the rotating magnetic field generated by the step signal.

  By the way, when used for gas flow rate adjustment as in the conventional motor 100, the female screw 140a screwed on the inner peripheral surface 20c of the rotor supporter 20d and the outer screw surface 40c of the lead screw 40 are screwed. A multi-thread screw 140 is used as the male screw 140b. By using this multi-thread screw 140, a large lead can be taken, and when the rotary motion of the rotor 20 is converted into a linear motion via the lead screw 40, the lead screw 40 can be smoothly advanced and retracted in the axial direction. As shown in FIG. 7B, the valve can be reliably shut off by the biasing of the return spring 160 in the event of an earthquake, gas leak, or power failure.

  However, as in the case of the conventional motor 100, when the rotational motion of the rotor 20 is converted into a linear motion via the lead screw 40, the lead screw 40 is urged in a direction away from the one end 20 a of the rotor 20. If the coaxiality between the rotor 20 and the ball bearing that supports the rotor 20 shifts, the ball bearing is distorted in the circumferential direction, and the return of the lead screw 40 due to the bias of the return spring 160 is caused. Time variation is increasing.

Therefore, as in the conventional motor 100, a bearing case 50b having a ball bearing 80 is disposed on the one end portion 20a side in the axial direction of the rotor 20, and the ball bearing 80 is disposed on the other end portion 20b side. The provided bearing case 50c is disposed to suppress the deviation of the coaxiality between the rotor 20 and the ball bearing 80 that supports the rotor 20, thereby preventing the circumferential deformation of the ball bearing 80. .
Was prevented from occurring.

  However, in the conventional motor 100, since the casing 50 in which the rotor 20 is installed and the bearing cases 50b, 50c in which the ball bearing 80 is installed are separately formed and assembled, quality variation and assembly Due to the failure, the coaxiality between the rotor 20 and the ball bearing 80 that rotatably supports the rotor 20 is likely to be displaced, and the ball bearing 80 is distorted in the circumferential direction. There is a problem that there is a high possibility that the variation in the return time of the screw 40 increases, and in the manufacturing process, it is necessary to pay attention to the assembly of the motor itself, which makes it difficult to achieve work efficiency and increases the manufacturing cost. There is also a problem.

  Further, in the ball bearing 80 used in the conventional motor 100, if there is an internal clearance, the play of the ball is large and the structure of the bearing is weak, so that the rotational vibration of the rotor 20 becomes large. Therefore, a load (preload) is applied in a direction parallel to the bearing central axis of the ball bearing 80 (axial direction), and the preload is intended to reduce vibration and improve acoustic performance. In the conventional motor 100 described above, the pressing member 60 provided in the bearing case 50b is fixed by the push washer 170, thereby performing the fixed position preload to apply the preload.

  However, this fixed position preload is simple, but the expansion and contraction may occur due to temperature change, and the amount of preload may change. There is a problem that preload loss may occur. On the other hand, constant pressure preload that uses coil springs or wave washers to apply preload has the advantage that there is little change in the amount of preload due to temperature, but there are problems of increased components and relatively low rigidity. .

  Further, in the conventional motor 100, the holding member 60 provided in the bearing case 50b, which is disposed on the opening 50a side of the casing 50, in order to preload the bearing 80 supporting the rotor 20 at a fixed position. The position of the rotor 20 is fixed by a push washer 170. However, when the rotor 20 rotates, the step signal is alternately input to the A phase and the B phase. , A force that moves in the direction toward the one end 20a and the direction toward the other end 20b acts, and the push washer 170 may come off due to this force. This is because the detachment force of the push washer 170 is proportional to the spring force of the push washer 170 and needs to be used within the elastic limit value of the push washer 170. Therefore, in the unlikely event that the push washer 170 is deformed to the plastic region, it is detached from the bearing case 5b, and the gas flow path cannot be adjusted.

JP-A-9-312963

  The present invention has been made in view of such circumstances, and can easily adjust the coaxiality of the rotor and the support member that supports the rotor to reduce variations in the return time of the lead screw by the biasing member. It is an object of the present invention to provide a motor capable of achieving the above.

In order to solve the above-mentioned problems, a first aspect of the present invention provides a cylindrical stator having a bottomed cylindrical casing, and a cylindrical rotor that is rotatably accommodated in the stator via a gap. And a lead screw that is arranged coaxially with the axis of the rotor and that is screwed into the inner peripheral surface of the rotor and extends from one end of the rotor so as to be able to advance and retract. In the motor in which a cylindrical guide member in which the leading end side of the lead screw extends so as to freely advance and retract is provided in the opening of the rotor, the rotor is provided with support members at both ends in the axial direction. One is a bearing that supports the one end side, and the other end of the support member is a conical first recess provided on the other end on the same axis as the axis of the rotor, and an inner circumference of the first recess Abutted against the surface A ball and an inner peripheral surface of the ball are abutted with each other, and a conical second recess is formed oppositely on the coaxial line of the first recess, and is biased toward the other end of the rotor. The guide member is fixed by a push washer, and burrs generated when the push washer is pressed bite into the inner peripheral surface of the casing. Is prevented from falling off .

  According to a second aspect of the present invention, in the first aspect of the present invention, a plurality of female screws are screwed on the inner peripheral surface of the rotor, and a plurality of male screws are formed on the outer peripheral surface of the lead screw. A screw is screwed, and the rotor and the lead screw are screwed together by a multi-thread screw.

  The invention according to claim 3 is the invention according to claim 1 or 2, wherein the lead screw has a valve member integrally provided at the tip, and the valve member and the guide member. An urging member is interposed between the two.

According to the first to third aspects of the present invention, one of the support members that rotatably support the rotor is a bearing that supports one end of the rotor, and the other is the axis of the rotor at the other end. A conical first recess provided on a coaxial line, a ball in contact with the inner peripheral surface of the first recess, an inner peripheral surface of the ball in contact with the first recess, and facing the first recess A conical second concave portion is formed, and is supported by a pressing member biased by a biasing member on the other end side of the rotor and disposed in the casing. It is possible to reduce problems during assembly, and on the other end side, the ball in contact with the inner peripheral surfaces of the first recess and the second recess by the pressing force of the pressing member is used in the thrust direction. Load and radial load In addition to being able to be received, when the component of the pressing force of the biasing member passes through the center of the ball, an automatic centering force works, and the rotor and the bearing supporting the rotor are coaxial. The occurrence of misalignment can be suppressed, and the circumferential distortion of the bearing can be prevented. Thereby, the dispersion | variation in the return operation time by the urging | biasing member of a lead screw can be reduced.

  In addition, since the bearing is disposed only on the one end side of the rotor, the manufacturing cost can be reduced, and the preload of the bearing can be reduced by the constant pressure preload by the biasing member that biases the pressing member. In addition, since the fixed position preload is performed by the guide member that is in contact with and fixed to the bearing, the biasing member can suppress a change in the preload amount due to the influence of thermal expansion or the like even in a place where the temperature changes rapidly. At the same time, the guide member can increase the rigidity. As a result, it is possible to improve durability and enable use in places where the influence of temperature change is large.

  According to the invention described in claim 2, a plurality of female screws are screwed on the inner peripheral surface of the rotor, and a plurality of male screws are screwed on the outer peripheral surface of the lead screw, Since the rotor and the lead screw are screwed together by a multi-thread screw, the lead of the screw can be taken large, and the lead screw can be easily moved along the axial direction of the rotor by a small rotation of the rotor. It can be extended freely. Thereby, fine flow path adjustment can be performed.

  According to a third aspect of the present invention, the lead screw has a valve member integrally provided at the tip thereof, and an urging member is interposed between the valve member and the guide member. Therefore, when the energization of the motor is cut off in the event of an earthquake, gas leakage, or power failure and the rotational torque of the rotor is released, the lead screw is advanced by the biasing member and the rotor is rotated to automatically The flow path can be closed. As a result, it is possible to prevent secondary disasters caused by gas leakage after a power failure.

According to the invention described in any one of claims 1 to 3, the guide member is fixed by the burr generated at the time of press cutting of the push washer biting into the inner peripheral surface of the casing. Even when the push washer's detachment force is deformed to the plastic region of the push washer, the burrs whose hardness has been increased by plastic hardening bite into the inner peripheral surface of the case sink, so that the detachment force does not decrease and is stable. The stopping force can be maintained. As a result, the degree of freedom of design can be increased even with the push washer that is required to be used within the elastic limit value in design.

It is front sectional drawing which shows one Embodiment of the motor of this invention. It is front sectional drawing which shows the state which mounted | wore the gas flow-path pipe | tube of the motor of FIG. It is a schematic diagram which shows the component force of the pressing force by a spring. This is a diagram of the balance of forces. It is a schematic diagram which shows the state which made the burr | flash of a push washer bite into the internal peripheral surface of a casing. It is front sectional drawing of the motor for the conventional flow adjustment of gas. It is front sectional drawing which shows the state which mounted | wore the gas flow path pipe with the motor of FIG.

  As shown in FIG. 1, a motor 1 of the present invention includes a cylindrical stator 3 in a bottomed cylindrical casing 5, and a rotor 2 rotatably accommodated in the stator 3 via a gap, A lead screw 4 is disposed on the same axis as the axis of the rotor 2 and is screwed into the inner peripheral surface 2c of the rotor 2 so as to extend forward and backward from one end 2a of the rotor 2. In addition, a cylindrical guide member 6 is disposed in the opening 5a of the casing 5 so that the tip 4a side of the lead screw 4 extends forward and backward.

  Here, the rotor 2 is composed of a rotor magnet 2e and a cylindrical rotor supporter 2d made of synthetic resin integrally provided with the rotor magnet 2e. The rotor 2 is provided with a bearing 8 on one end 2a side. A conical first recess 12 is integrally provided on the other end 2b side of the rotor 2 on the same axis as the axis of the rotor 2, and the pressing member 10 is disposed opposite to the first recess 12. Has been.

  And the conical recessed part 13 is opposingly arranged on the said coaxial line in the opposing surface with the other end part 2b of the rotor 2 of the holding member 10, and the spring which urges | biases the 2nd recessed part 13 to the 1st recessed part 12 11 is interposed. Further, between the first recess 12 and the second recess 13, a ball 9 that is in contact with each inner peripheral surface and is urged by the spring 11 of the pressing member 10 is interposed. This ball 9 is a steel ball.

  Further, four female screws 14a are screwed on the inner peripheral surface 2c of the rotor supporter 2d. Then, four male screws 14b are screwed on the outer peripheral surface 4c on the base end 4b side of the lead screw 4 screwed to the inner peripheral surface 2c. The four-thread screw 14 has, for example, M3.5, a hole diameter 3, and a screw pitch 3.84. The lead screw 4 is integrally provided with a valve member 15 at its tip 4a. Further, a rotation-preventing pin 4d that prevents accompanying rotation when the rotor 2 rotates is fitted in a hole formed in the radial direction at approximately the center in the axial direction of the lead screw 4. Both end portions of the rotation stop pin 4d are disposed so as to protrude from the outer peripheral surface 4c of the lead screw 4.

  The guide member 6 that seals the opening 5a of the casing 5 is formed in a cylindrical shape. From the center part of the guide member 6, the tip 4a side of the lead screw 4 is extended so as to freely advance and retract. Further, a groove 6c is formed in the axial direction on the inner peripheral surface of the guide member 6, and the groove 6c is disposed to face the circumferential direction. The groove 6 c prevents the lead screw 4 from rotating along with the rotor 2 by inserting both ends of the rotation-preventing pin 4 d inserted and fitted in the radial direction of the lead screw 4.

  The one end 6 a side of the guide member 6 is in contact with the bearing 8. Further, the other end portion 6b side of the guide member 6 is formed in a convex shape, and a push washer 17 is fitted therein. The push washer 17 has an edge formed in a square shape in a sectional view, and a burr 17a generated when the press was cut is formed on the inner peripheral surface of the casing 5 as shown in FIG. It bites in and is fixed.

  Further, a return spring 16 is disposed on the distal end 4 a side of the lead screw 4 between the valve member 15 and the guide member 6 so as to be opened.

  Further, the cylindrical stator 3 is provided in a substantially cylindrical cup 5b. The cup 5 b is integrally provided so as to surround the outer peripheral surface of the casing 5. The stator 3 is isolated from the casing 5 and disposed in the cup 5b. In the stator 3, a bobbin 3b made of synthetic resin is integrally formed on the outer periphery of two pairs of field plates 3a, and a coil 3c is wound around the outer periphery of the bobbin 3b. A plurality of pole teeth 3d are alternately arranged at equal intervals on the inner peripheral surface of each field plate 3a. Reference numeral 18 denotes a terminal to which the end of the copper wire of the coil 3c is connected.

  In order to adjust the flow rate of the gas passage tube t using the motor 1 having the above configuration, first, the motor 1 is mounted on the gas passage tube t as shown in FIG. Then, by supplying electricity to the motor 1, a step signal is input to the coil 3c. By this input, the pole teeth 3d of the field plate 3a become N pole and S pole, and a rotating magnetic field is generated. Since the rotor magnet 2e is alternately magnetized to the N pole and the S pole, the rotation of the rotor 2 is continued in synchronization with the rotating magnetic field generated by the step signal.

  At this time, since the step signal is alternately input to the A phase and the B phase, the step signal is supported between the ball bearing 8 and the first concave portion 12 and the second concave portion 13 through the ball 9 by the bias of the spring. A force is generated to move the rotor 2 along the axial direction in the direction toward the one end 2a and the direction toward the other end 2b. However, the rotor 2 is driven by the guide member 6 fixed by the push washer 17 disposed on the one end portion 2a side and the urging by the spring 11 of the pressing member 10 disposed on the other end portion 2b side. 2 is restricted from moving in the axial direction, and a constant position preload and a constant pressure preload are applied to the bearing 8, thereby improving the shaft deflection accuracy of the rotor 2 and the bearing 8.

  Further, a ball is interposed between a conical recess 12 in which the other end 2 b side of the rotor 2 is fitted to an axis of the other end 2 b and a conical recess 13 formed in the pressing member 10. 9, the ball 9 supports the thrust direction and the radial direction, and as shown in FIG. 3, the spring force of the spring 11 is supported. The center of the rotor 2 is automatically aligned by the force f received at the center of the ball 9.

  Then, in order to adjust the gas flow rate, the rotor 2 is rotated, and the lead screw 4 screwed into the inner peripheral surface 2c of the rotor supporter 2d is moved along the axial direction of the rotor 2 by this rotation angle. The rotor 2 extends from the one end 2a side so as to freely advance and retract. At this time, the lead screw 4 tries to rotate with the rotor 2, but the rotation stop pin 4 d disposed at the center in the axial direction of the lead screw 4 is inserted into the groove 6 c of the guide member 6. Therefore, the lead screw 4 can extend in the axial direction of the rotor 2 without being accompanied by the rotation of the rotor 2.

  Further, four female screws 14a are screwed on the inner peripheral surface 2c of the rotor supporter 2d, and four male screws 14b are formed on the outer peripheral surface 4c of the lead screw 4. With the screw 14, the lead screw 4 can be efficiently extended and retracted with a small rotation angle.

  In addition, in the event of an earthquake, gas leakage, power failure, etc., the stator 3 is de-energized, the rotational torque of the rotor 2 is released, and the return spring 16 disposed between the valve member 15 and the guide member 6 By urging, the lead screw 4 advances from the one end 2a side of the rotor 2, and the valve member 15 blocks the gas flow path.

Here, the reason why the four-thread screw 14 is used for the rotor supporter 2d and the lead screw 4 is that the load F of the return spring 16 can be reduced by using the four-thread screw 14.
This can be explained by determining the return spring force of the return spring 16 based on the diagrammatic force balance equation shown in FIG.

The schematic balance equation of FIG.
Fcosα−Wsinα = μ (Fsinα + Wcosα)
W = F × (cosα−μsinα) / (μcosα + sinα)
= F × (1−μtan α) / (μ + tan α)
= F × (1-tanφtanα) / (tanφ + tanα)
= F / tan (φ + α)
Propulsive force W = F / tan (α + φ)
W: Axial load (kg)
F: Tangent force (kg)
α: Lead angle
φ: Friction angle F = T / r
T: Torque (kg)
r: Screw hole diameter / 2

From the above calculation formula, when the return spring force W is obtained,
For the standard pitch of M3.5 4-thread,
Perforated diameter 3 r = 0.15 (coefficient of friction)
Standard pitch 0.6
tan ⁻¹ θ = 0.6 / 3 / π = 0.0637 θ = 3.6 °

In the case of the pitch of the present invention of M3.5 4-thread,
Perforated diameter 3 r = 0.15 (coefficient of friction)
Screw pitch of the present invention 3.84
tan ⁻¹ θ = 3.84 / 3 / π = 0.407 θ = 22.1 °
Note that the angle is generally around 8 ° due to the friction angle between the SUS screw and the resin or grease lubrication. (Friction coefficient is 0.15)

W> P / tan (α + φ)
W: Return spring force From the above formula,
When screw pitch is 0.6 W = P / 0.205 = 4.88P
When screw pitch is 3.84 W = P / 0.580 = 1.97P
Accordingly, when the screw pitch of the present invention is set for the rotor 2 detent torque, the return spring force can be reduced to about 1 / 2.5 with respect to the standard screw, which is advantageous in terms of structural strength.

  Thus, when the rotational torque of the rotor 2 is released in an emergency without increasing the spring force of the return spring 16, the lead screw 4 automatically advances from the one end 2 a side of the rotor 2 and the lead screw 4. The rotor 2 that is screwed into the rotor rotates, and the valve member 15 that is provided integrally with the tip 4a of the lead screw 4 blocks the flow path. At this time, the rotor 2 is supported by the bearing 8 on the one end 2a side and supported by the ball 9 on the other end 2b side. Therefore, the rotor 2 and the bearing 8 are automatically aligned. There is no deviation of the coaxiality, and variations in return time due to the return spring 16 are reduced.

  Further, after the rotor 2 is disposed in the casing 5, when the opening 5a of the casing 5 is sealed by the guide member 6, as shown in FIG. Fix to the casing 5. At this time, by pressing the burr 17a surface generated at the time of press cutting against the inner peripheral surface of the casing 5, it is possible to double the strength against the pulling direction j.

  This is because the burr 17a generated during the press cutting of the push washer 17 surely increases its hardness by plastic hardening, and is about 200 in the micro Vickers, whereas the inner peripheral surface of the casing 5 is deep drawn. This is because the hardness is about 120 in Micro Vickers in order to perform stress removal. Thereby, the edge part of the push washer 17 will surely bite into the inner peripheral surface of the casing 5, and the detachment resistance of the push washer 17 will be improved.

  When the burr 17a does not bite into the inner peripheral surface of the casing 5 in the detachment resistance, the detachment force Fh = μ × F, and the detachment force is proportional to the spring force of the push washer 17. Therefore, in terms of design, it is necessary to use the push washer 17 in the spring property (within the elastic limit value). However, by actively using the burr 17a, μ> 1 or less, and even if the push washer 17 is deformed to the plastic region, the detachment force does not decrease and a stable stopping force can be maintained.

  According to the motor 1 according to the above-described embodiment, one of the support members 7 that rotatably supports the rotor 2 is the ball bearing 8 that supports the one end 2a side of the rotor 2, and the other is the other end 2b. A conical first recess 12 provided on the same axis as the axis of the rotor 2, a ball 9 in contact with the inner peripheral surface of the first recess 12, and an inner peripheral surface in contact with the ball 9 At the same time, a conical second concave portion 13 is formed oppositely on the axis of the first concave portion 12 and is supported by the holding member 10 biased by the spring 11 on the other end 2b side of the rotor 2. Since it is disposed in the casing 5, it is possible to reduce problems when the motor 1 is assembled, and on the inner peripheral surfaces of the first recess 12 and the second recess 13 on the other end 2 b side, For urging the holding member 10 The ball 9 that comes into contact with each other can receive a load in the thrust direction and a load in the radial direction, and the component of the pressing force of the spring 11 passes through the center of the ball 9, thereby automatically aligning the force. Therefore, it is possible to suppress the deviation of the coaxiality between the rotor 2 and the ball bearing 8 supporting the rotor 2, and to prevent the ball bearing 8 from being distorted in the circumferential direction. Thereby, the dispersion | variation in the return operation time by the return spring 16 of the lead screw 4 can be reduced.

  Further, since the bearing 8 is disposed only on the one end portion 2a side of the rotor 2, the manufacturing cost can be reduced, and the constant pressure preload by the spring 11 that presses the preload of the bearing 8 and biases the member 10, and the bearing 8 Since it is performed by the fixed position preload by the guide member 6 that is in contact with and fixed to the spring, the change in the preload amount due to the influence of thermal expansion or the like can be suppressed even in a place where the temperature changes drastically by the spring 11 and the guide member. 6 can increase the rigidity. As a result, it is possible to improve durability and enable use in places where the influence of temperature change is large.

  Then, four female screws 14a are screwed on the inner peripheral surface 2c of the rotor 2, and four male screws 14b are screwed on the outer peripheral surface 4c of the lead screw 4, so that the rotor 2 and the lead screw 4 are provided. Are screwed together by a four-thread screw, so that the lead of the screw can be made large, and the lead screw 4 can be easily extended and retracted along the axial direction of the rotor 2 by a small rotation of the rotor 2. Can be issued. Thereby, fine flow path adjustment can be performed.

  Furthermore, since the lead screw 4 has a valve member 15 integrally provided at the tip 4a thereof and a return spring 16 is interposed between the valve member 15 and the guide member 6, an earthquake or gas When the motor 1 is de-energized at the time of leakage or power failure and the rotational torque of the rotor 2 is released, the lead spring 4 is advanced by the return spring 16 and the rotor 2 is rotated to automatically flow the flow path. Can be closed. As a result, it is possible to prevent secondary disasters caused by gas leakage after a power failure.

  Further, since the guide member 6 is fixed by the burr 17a generated when the push washer 17 is pressed and cut into the inner peripheral surface of the casing 5, the disengagement force of the push washer 17 causes the plasticity of the push washer 17 to be plastic. Even in the case of deformation to the region, the burr 17a whose hardness has been increased by plastic hardening bites into the inner peripheral surface of the case sink 5, so that it is possible to maintain a stable stopping force without reducing the detachment force. As a result, it is possible to increase the degree of freedom of design even with the push washer 17 that needs to be used within the elastic limit value in terms of design.

  In addition, in the said embodiment, although demonstrated only when using the structure which isolated the stator 3 installed in the cup 5b from the rotor 2 installed in the casing 5, it is not limited to this, For example, Even if it arrange | positions in the casing 5 without isolating the stator 3 and the rotor 2, it can respond.

  It can be used for a motor that adjusts the flow rate of gas such as gas.

DESCRIPTION OF SYMBOLS 1 Motor 2 Rotor 2a One end part 2b Other end part 2c Inner peripheral surface 2d Rotor supporter 2e Rotor magnet 3 Stator 4 Lead screw 4a Tip 4b Base end 4c Outer peripheral surface 5 Casing 5a Inner peripheral surface 6 Guide member 6a Groove part 7 Bearing member 8 Bearing 9 Ball 10 Holding member 11 Return spring (urging member)
12 1st recessed part 13 2nd recessed part 14 Multi-thread screw 15 Valve member 16 Spring (biasing member)
17 Push Washer 17a Bali

Claims (3)

A cylindrical stator having a bottom, a cylindrical stator, a cylindrical rotor rotatably accommodated in the stator via a gap, and an axis coaxial with the axis of the rotor, A lead screw that is screwed into the inner peripheral surface of the rotor and extends from one end of the rotor so as to freely advance and retreat, and a cylinder whose tip end side of the lead screw extends so as to freely advance and retract from the opening of the casing. In a motor provided with a guide member,
The rotor is provided with bearing members at both ends in the axial direction, one of the bearing members is a bearing that supports the one end side, and the other end of the bearing member is the other end of the axis of the rotor. And a conical first recess provided on a coaxial line, a ball in contact with the inner peripheral surface of the first recess, an inner peripheral surface of the ball in contact with the ball, and the first recess A conical second recess is formed oppositely on the coaxial line, and is supported by a pressing member biased by a biasing member on the other end side of the rotor . The guide member is a push washer. And a burr generated when the push washer is press-cut into the inner peripheral surface of the casing to prevent the burr from falling off . With multiple thread of the female screw on the inner peripheral surface of the rotor are screwed on the outer peripheral surface of the lead screw multiple thread of the male thread is screwed, by the rotor and the lead screw and multi-threaded screw The motor according to claim 1, wherein the motor is screwed.   The lead screw has a valve member integrally provided at the tip, and an urging member is interposed between the valve member and the guide member. The motor described.

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