JP4914583B2 - Motor actuator - Google Patents

Description

In the present invention, an actuator case is formed by a motor case and a gear case, and a motor and a gear portion are arranged inside the actuator case. The rotation of the motor is decelerated by the gear portion, and the decelerated motor rotation is output. Regarding a motor actuator that outputs to the outside via a gear, such a motor actuator is formed independently and attached to various devices.
Thus, the rotation members provided in various devices are rotationally controlled by the motor of the motor actuator.

A first example of a conventional motor actuator is shown in FIG.
Reference numeral 20 denotes a motor case in which the motor M is housed and disposed, and a motor housing recess 20b is formed toward the left opening end 20a in the drawing.
A motor M such as a step motor having an output shaft Ma is inserted and disposed in the motor housing recess 20b.
Reference numeral 21 denotes a gear case in which the gear portion G is housed and arranged, and a gear housing recess 21b is formed toward the right opening end 21a in the drawing.
The opening end 20a of the motor case 20 and the opening end 21a of the gear case 21 are brought into contact with each other to form an actuator case K. The motor and the gear portion G are housed and arranged inside the actuator K. Will be.
The gear portion includes a motor gear G1, an intermediate gear G2 rotatably supported on the support shaft 22, and an output gear G3 having a rotation transmission hole G3a. Is connected to the output shaft Ma of the motor M and meshed with one side of the intermediate gear G2, and the other side of the intermediate gear G2 is meshed with the output gear G3.
A mounting boss 23 having a mounting hole 23a is integrally formed at the opening end 20a of the motor case 20, and a mounting boss 24 having a mounting hole 24a is integrally formed at the opening end 21a of the gear case 21. Since the motor case 20 and the gear case 21 are arranged in contact with each other with the open ends 20a and 21a, a mounting hole 25 (formed by the mounting holes 23a and 24a) is formed in a part of the actuator case K. Mounting bosses 26 (formed by mounting bosses 23, 24) are formed.
As described above, a motor actuator including the gear portion G and the motor M is formed inside the actuator case K. The motor actuator has the end face of the mounting boss 26 in contact with the device W, and the mounting hole is in this state. Bolts 27 are inserted into 25, and the mounting bosses 26 are screwed and fixed to the equipment W by the bolts 27.
On the other hand, one end of the rotation shaft Wa provided in the device W is inserted and arranged in the rotation transmission hole G3a of the output gear G3. In this insertion, the cross-sectional shape of the rotation transmission hole G3a is a non-circular hole. This is done by making the cross-sectional shape oval, and the rotation of the output gear G3 is transmitted to the rotating shaft Wa.
According to the above, the rotation of the motor M is decelerated by the gear portion G, the decelerated rotation is transmitted to the rotation shaft Wb via the output gear G3, and the rotation shaft Wa of the device W is rotated according to the rotation of the motor M. Can be controlled.

A second example of a conventional motor actuator is shown in FIG.
Reference numeral 30 denotes a case in which the motor M and the gear portion G are housed and arranged, and a housing recess 30b is provided toward the left opening end 30a.
In the storage recess 30b, a motor M such as a step motor having an output shaft Ma is disposed and a gear portion G is disposed. The gear portion G includes a motor gear G1 and a support shaft 31. And an output gear G3 having a rotation transmission hole G3a.
Among these, the intermediate gear G2 is formed with a large-diameter gear G2a and a small-diameter gear G2b in two stages in the longitudinal axis direction of the support shaft 31. Thus, the motor gear G1 is meshed with the large-diameter gear G2a of the intermediate gear G2, and the small-diameter gear G2b of the intermediate gear G2 is meshed with the output gear G3. Then, the cover 32 is disposed in contact with the open end 30a of the case 30 to close the open end 30a of the case 30, thereby forming the actuator case K. In the closed storage space of the actuator case K, The motor and the gear portion G are housed and arranged.
A mounting boss 33 having a mounting hole 33a is integrally formed at the opening end 30a of the case 30, and a mounting boss 34 having a mounting hole 34a is integrally formed at the opening end 32a of the cover 32. In this case, the case 30 and the cover 32 are arranged in contact with each other with the open ends 30a and 32a, so that a part of the actuator case K is formed with a mounting hole 35 (mounting holes 33a and 34a). Mounting boss 36 (formed by mounting bosses 33, 34).
As described above, a motor actuator including the gear portion G and the motor M is formed inside the actuator case K. The motor actuator has the end face of the mounting boss 36 in contact with the device W, and the mounting hole is in this state. Bolts 27 are inserted into 35, and the mounting bosses 36 are screwed and fixed to the equipment W by the bolts 27.
On the other hand, one end of the rotation shaft Wa is inserted into the rotation transmission hole G3a of the output gear G3 in the same manner as described above.
According to the above, the rotation of the motor M is decelerated by the gear portion G, the decelerated rotation is transmitted to the rotation shaft Wb via the output gear G3, and the rotation shaft Wa can be controlled to rotate according to the rotation of the motor M.

The first example of such a conventional motor actuator has the following problems.
In recent years, with the improvement of injection molding technology using synthetic resin materials, gears are formed of synthetic resin materials, and the motor gear G1, intermediate gear G2, and output gear G3 constituting the gear portion G are made of synthetic resin materials. It is formed.
Here, when the weight Gw of the gear part G is compared with the weight Mw of the motor M, the weight Mw of the motor M is formed to be heavier than the weight Gw of the gear part G.
The heavy motor M is housed in the motor housing recess 20b and is disposed so as to protrude rightward from the opening end 20a of the motor case 20.
On the other hand, mounting bosses 26 for attaching the motor actuator to the device W are formed at the opening end 20 a of the motor case 20 and the opening end 21 a of the gear case 21.
According to the above,
(1) When the motor actuator is attached and fixed to the device W, a large eccentric load is applied to the mounting boss 26 by the motor M, and a large bending moment acts on the mounting boss 26. For this reason, it is necessary to increase the rigidity of the mounting boss 26 and increase the size of the mounting boss 26, which increases the weight of the motor actuator and cannot be made compact.
This is a serious problem when the motor actuator is attached to a device with intense vibration.
(2) The motor M is inserted into the motor case 20 in a light press-fit state. However, when the motor M is completely inserted into the motor housing recess 20b from the opening end 20a of the motor case 20, the motor M is inserted. M insertion workability cannot be improved.
That is, when the motor M is inserted into the motor housing recess 20b, the outer periphery of the motor M cannot be gripped by a jig or the like until the end of the insertion.

The second example of the conventional motor actuator has the following problems.
(1) All of the motor M and the gear part G are arranged in the case 30. According to this, when the motor actuator is fixed to the device W via the mounting boss 36, the motor M and the gear part G are attached. A particularly large offset load is applied to the boss 36, and a large bending moment acts on the mounting boss 36. According to the above, it is necessary to increase the size of the mounting boss 36 in the same manner as in the conventional example, and the motor actuator cannot be assembled in a lightweight and compact manner.
(2) The left end surface Ml of the motor M is arranged to face the right end of the small-diameter gear G2b formed in two stages in the longitudinal axis direction XX of the support shaft 31, and according to this, the motor M And the gear portion G2 must have a large overall axial length L, and the motor actuator cannot be made compact.
This is because the gear width G2w of the intermediate gear G2 and the width Mw of the motor M are required.
(3) When the motor M is inserted into the housing recess 30b of the case 30, since the entire outer periphery of the motor M is inserted into the storage recess 30b, the outer periphery of the motor M cannot be gripped to the end by a jig or the like. The workability of inserting the motor M into the case 30 cannot be improved.

  The motor actuator according to the present invention is made in view of the above problems, and can reduce the rotation of the motor by two stages, and with respect to the mounting boss formed at the opening end of the motor case and the gear case. In particular, the main object is to provide a lightweight and compact motor actuator with high vibration resistance by reducing the application of an offset load from the motor case side.

In order to achieve the above object, the present invention accommodates a motor and a gear portion that decelerates the rotation of the motor and transmits it to the rotating shaft of the device in the actuator case. Motor gear connected to the output shaft, a two-stage intermediate gear supported on a support shaft attached to the actuator case, and an output gear connected to the rotary shaft, and the two-stage intermediate gear A large-diameter gear that meshes with the motor gear, and a small-diameter gear that is integrally formed on one side of the large-diameter gear and meshes with the output gear. in the motor actuator forming a mounting boss that is, Motake with the actuator casing, motors accommodating recess and the first open end which opens the motor accommodation recess If, gearing housing recess and the gear housing recess is constituted by a gear case having a second opening end which opens, in the motor accommodation recess housed in pressed-in condition the motor from the first open end and said The gear housing recess accommodates the gear portion from the second opening end, and the motor case includes first and second bosses that are bolted to each other so that the first and second opening ends are in contact with each other. And the first and second bosses form the mounting boss, and the small-diameter gear is opposite to the tooth portion with the output shaft and the tooth portion engaging the output shaft. A small radius portion having a radius smaller than the radius of the tooth portion , and the outer peripheral surface of one end portion on the first opening end side of the motor is close to the outer peripheral surface of the small radius portion. Opposite to the one end The first feature that the end face is arranged adjacent opposed to one side surface of the large diameter gear connected to the small radius portion.
In addition to the first feature, the present invention has a second feature in that the one end portion of the motor protrudes from the first opening end toward the gear receiving recess.

According to the first feature of the present invention, the gear portion includes a motor gear connected to the output shaft of the motor, and a small diameter gear and a large diameter gear formed in two stages along the longitudinal direction of the support shaft. Two-stage intermediate gears and an output gear that outputs rotation toward the outside.
According to the above, the rotation of the motor is reduced by one step by the motor gear and the large diameter gear of the intermediate gear, and further reduced by two steps by the small diameter gear and the output gear of the intermediate gear.
Therefore, the rotation of the motor can be greatly decelerated, and the range of deceleration use as a motor actuator can be expanded.
Also, the first opening end side of the motor disposed in the motor housing recess of the motor case is connected to the second opening end of the large-diameter gear of the two-stage intermediate gear housed in the gear housing recess of the gear case. according to close opposed to the side surface side, the center of gravity of the motor can be arranged close to the first opening end side of the motor case, the bending moment due to an unbalanced load with respect to the mounting boss thereby formed in the actuator casing The vibration resistance of the motor actuator can be improved when the motor actuator is attached to a device, and the mounting boss is prevented from being enlarged, so that the motor actuator can be made lighter and compact.
Further, according to the above, the total axial length of the motor and the gear portion is determined by the gear width of the large-diameter gear of the intermediate gear and the width of the motor, thereby reducing the overall width of the actuator case. In addition to the above, the motor actuator can be gathered in a light weight and compact.
As described above, according to the fact that the motor actuator can be made light and compact, the degree of freedom of arrangement and mounting of the motor actuator in a narrow space can be greatly improved.

  According to the second feature of the present invention, when the motor is inserted into the motor housing recess of the motor case by projecting the one end of the motor from the first opening end toward the gear housing recess, Since the outer periphery of the motor can be gripped by a jig or the like until the end of the insertion, the insertion workability can be improved and the motor can be accurately inserted into the motor housing recess.

An embodiment of a motor actuator according to the present invention will be described below with reference to FIG.
Reference numeral 1 denotes a motor case in which the motor M is housed and arranged. Reference numeral 2 denotes a gear case in which the gear portion G is housed and arranged. The first opening end 1a of the motor case 1 and the second opening of the gear case 2 are arranged. An actuator case A having a storage space is formed by abutting the end 2a.
The gear housing recess 2b provided in the gear case 2 is rotatably supported by the smallest diameter motor gear G1 connected to the protruding end of the output shaft Ma of the motor M and the support shaft 3 attached to the actuator case A. The two-stage intermediate gear G2 that is formed, the output gear G3 in which the rotation transmission hole G3a having a cross-sectional shape of a non-circular hole is formed, and the gear portion G are arranged. Among these, in the two-stage intermediate gear G2, the large-diameter gear G21 and the small-diameter gear G22 are formed in parallel in two stages along the longitudinal direction XX of the support shaft 3.
Here, in particular, the small-diameter gear G22 of the two-stage intermediate gear is disposed on the second opening end 2a side (to the left of the gear case 2) of the gear case 2, and the large-diameter gear G21 is disposed on the bottom 2b1 side (gear of the gear housing recess 2b). It is arranged on the right side of case 2).
According to the gear portion G configured as described above, the motor gear G1 and the large-diameter gear G21 of the two-stage intermediate gear G2 are meshed and subjected to primary reduction, and further, the small-diameter gear G22 of the two-stage intermediate gear G2 and the output gear G3 are meshed. To decelerate two steps. The small-diameter gear G22 has a tooth portion G22a that meshes with the output gear G3, and a small-radius portion G22b that is opposite to the tooth portion G22a across the support shaft 3 and has a smaller radius than the radius of the tooth portion G22a .

In the motor housing recess 1b of the motor case 1, a motor M such as a step motor is inserted and arranged from the first opening end 1a side in a light press-fit state. At this time, the motor M has its first opening end. It arrange | positions so that the one end part Mb by the side of 1a may protrude from the said 1st opening end 1a to the said gear accommodation recessed part 2b side. The outer peripheral surface of the one end portion Mb on the first opening end 1a side of the motor M is in close proximity to the outer peripheral surface of the small radius portion G22b, and the end surface of the one end portion Mb is a large portion continuous with the small radius portion G22b. It will be in close proximity to one side surface of the radial gear G21.

  A first boss 7 with a hole 6 is integrally formed on the outer surface of the motor case 1 on the first opening end 1a side, and the outer surface of the gear case 2 on the second opening end 2a side is integrally formed. A second boss 5 having a hole 4 is integrally formed, and the actuator case A is formed by the first opening end 1a of the motor case 1 and the second opening end 2a of the gear case 2 being in contact with each other. Further, the first boss 7 and the second boss 5 constitute a mounting boss 8 of the actuator case A provided with a series of mounting holes 8 composed of the holes 6 and the holes 4.

As described above, the motor actuator A formed by arranging the motor M and the gear portion G in the actuator case A inserts the bolt 10 into the mounting hole 8 and also forms the female screw hole Wb formed in the device W. By screwing the bolt 10 toward the end, it is screwed and fixed to the device W via the mounting boss 9.
On the other hand, the external rotation shaft Wa is inserted and arranged in the rotation transmission hole G3a of the output gear G3, and rotates synchronously with the output gear G3.

According to the motor actuator of the present invention as described above, when the output shaft Ma rotates by driving the motor M, this rotation is decelerated by one stage by the large-diameter gear G21 of the motor gear G1 and the two-stage intermediate gear G2, and further Two-stage reduction is performed by the small-diameter gear G22 of the two-stage intermediate gear G2 and the output gear G3, and the rotational force of the output gear G3 that has been decelerated by two stages is output to the outside via the rotation shaft Wa.
According to the above, the gear portion G can be decelerated in two steps as desired, and the allowable range of the deceleration range can be increased.
Further, since the two-stage intermediate gear G2 is formed in parallel in two stages by the large-diameter gear G21 and the small-diameter gear G22 in the longitudinal direction XX of the support shaft 3, there is no need to perform the two-stage deceleration. However, the diameter of the gear in the diameter direction can be kept small, and the motor actuator can be compactly assembled.
Further, according to the two-stage deceleration, it is possible to prevent the distance H between the output shaft Ma of the motor M and the bolt 10 inserted into the mounting hole 8 from being increased. Can be lowered.
On the other hand, one end Mb on the first opening end 1a side of the motor M inserted and arranged in the motor housing recess 1b of the motor case 1 projects from the first opening end 1a toward the gear housing recess 2b and is intermediate. According to the fact that the large-diameter gear G21 of the gear G2 is disposed in close proximity to the side surface G21a on the second opening end 2a side, the center of gravity of the motor M is directed toward the first opening end 1a of the motor case 1 (rightward in the figure). This can reduce the effect of unbalanced load on the mounting boss 9, reduce the bending moment by the motor M, suppress the increase in size of the mounting boss 9, reduce the weight of the motor actuator and make it compact. Can be achieved. Further, according to the fact that the one end Mb of the motor M is disposed in close proximity to the side face G21a on the second opening end 2a side of the large-diameter gear G21, the two-stage intermediate gear G2 is constituted by the small-diameter gear G22 and the large-diameter gear G21. Even in the case of two stages formed in parallel, the other end Mc of the motor M in the longitudinal direction of the output shaft Ma of the motor M and the side G21b on the bottom side of the gear housing recess 2b of the large-diameter gear G21 (on the right end face) And the length L of the actuator case A can be reduced.
Further, since the one end Mb of the motor M is disposed so as to protrude from the first opening end 1a of the motor case 1 to the gear case 2 side, when the motor M is inserted into the motor housing recess 1b of the motor case 1, Since the outer periphery of the motor M can be gripped by a jig or the like until the end state, the operation of inserting the motor M into the motor housing recess 1b can be reliably and efficiently performed.

The longitudinal cross-sectional view which shows one Example of the motor actuator which becomes this invention. The principal part longitudinal cross-sectional view which shows the 1st example of the conventional motor actuator. The principal part longitudinal cross-sectional view which shows the 2nd example of the conventional motor actuator.

DESCRIPTION OF SYMBOLS 1 Motor case 1a 1st opening end 1b Motor accommodation recessed part 2 Gear case 2a 2nd opening end 2b Gear accommodation recessed part 3 Support shaft G Gear part G1 Motor gear G2 Two step intermediate gear G21 Large diameter gear G21a Side surface on the second opening end side G22 Small-diameter gear G22a Small-diameter gear tooth G22b Small- diameter radius portion of small- diameter gear G3 Output gear 8 Mounting hole 9 Mounting boss M Motor Ma Motor output shaft W Equipment Wa Equipment rotating shaft

Claims (2)

The actuator case (A) contains a motor (M) and a gear portion (G) that decelerates the rotation of the motor (M) and transmits it to the rotating shaft (Wa) of the device (W). A gear stage (G) is a two-stage intermediate supported by a motor gear (G1) connected to the output shaft (Ma) of the motor (M) and a support shaft (3) attached to the actuator case (A). A large-diameter gear (G2) configured with a gear (G2) and an output gear (G3) connected to the rotating shaft (Wa) and meshing the two-stage intermediate gear (G2) with the motor gear (G1) G21) and a small-diameter gear (G22) integrally formed on one side of the large-diameter gear (G21) and meshing with the output gear (G3), and at one end of the actuator case (A), Shaped mounting boss (9) to be bolted to equipment (W) In the motor actuator,
Said actuator case (A), Motor housing recess (1b) and the motor housing recess (1b) is first open end which opens to the motor case having a (1a) (1), gearing housing recess (2b) And a gear case (2) having a second opening end (2a) in which the gear receiving recess (2b) opens,
The motor (M) is accommodated in the motor accommodating recess (1b) in a press-fit state from the first opening end (1a), and the gear portion (G) is accommodated in the gear accommodating recess (2b). From the open end (2a),
The first and second bosses (7, 5), which are bolted to each other so that the first and second open ends (1a, 2a) are in contact with each other, are connected to the motor case (1) and the gear case (2). And the mounting boss (9) is constituted by the first and second bosses (7, 5),
The small diameter gear (G22), the output teeth meshing with the gear (G3) and (G22a), wherein the teeth across the support shaft (3) (G22a) and the teeth be in opposite (G22a ) And a small radius portion (G22b) whose radius is smaller than the radius of
The motor (M) is arranged so that the outer peripheral surface of the one end (Mb) on the first opening end (1a) side of the motor (M) is closely opposed to the outer peripheral surface of the small radius portion (G22b) and the one end A motor actuator characterized in that the end face of the portion (Mb) is arranged so as to face and oppose one side face of the large-diameter gear (G21) connected to the small radius part (G22b) . The motor actuator according to claim 1,
A motor actuator characterized in that the one end (Mb) of the motor (M) is projected from the first opening end (1a) toward the gear receiving recess (2b).

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