JP2016094832A - Motor drive unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor drive unit capable of suppressing the movement of a machine due to vibrations, even if vibrations hard to be suppressed by a balancer and the like are generated and transmitted to a supporting leg portion.SOLUTION: A motor drive unit is equipped with a plurality of support leg portion 20 fixed on a bottom surface of a unit body 11 to be grounded. The support leg portion 20 is equipped with an elastic member 21 formed with an insertion hole 21d, a collar member 22 attached to the insertion hole 21d, and a shaft member 23 penetrating the collar member 22 and fixed to the unit body 11. At least one of the elastic members 21, is equipped with a deformation promoting portion 21e which is asymmetrically formed about the insertion hole 21d and enabling the shaft member 23 to easily incline in a predetermined direction.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a motor drive device, and more particularly to a motor drive device having a feature in a support leg for suppressing movement of a machine due to vibration.

  For example, in an air compressor in which a compression unit is driven by an electric motor to compress air, vibration is generated with the operation of the compression unit driven by the electric motor. In order to absorb this vibration, there is known a device in which a support leg portion made of rubber or the like is provided on the bottom surface of the apparatus body (see, for example, Patent Document 1).

JP 2010-185447 A

  The support legs made of rubber absorb the vibration by compressing and deforming. However, if a flexible elastic body is used to enhance the effect of reducing the vibration, the shock absorbing performance against dropping or the like cannot be obtained, or the durability There is a problem that it becomes inferior.

For this reason, support legs having a certain rigidity are provided. However, vibration absorption may be insufficient, or a restoring force after compressive deformation may be large, which may cause the machine to move. If the machine is moved by vibration while the machine is in operation, the ground plane may be soiled or damaged. In addition, the moved machine may come into contact with or collide with the wall and damage the wall.
In particular, in recent years, since the weight of motor-driven devices has been reduced, there is a situation that such machine movement is likely to occur.

  Although it is possible to suppress the movement of the machine by increasing the ground contact area, it is limited to the installation location, such as being able to install only on a flat place, and it is effective for portable equipment It is not correspondence.

  In air compressors equipped with reciprocating pistons, the main sources of vibration are the inertial force of rotational motion such as motors and cranks, and the inertial force of reciprocating motion of pistons. Some have a balancer. Although it is possible to suppress vibration with a motor-driven device equipped with such a balancer, the balancer is set so as to be balanced at a predetermined reciprocating movement speed (that is, the rotation speed of the motor). If the rotational speed fluctuates greatly, the balance suppressor may not sufficiently exhibit the vibration suppressing effect.

  For example, an air compressor equipped with an inverter, which is often used in construction sites where the power supply environment is poor, is supplied when the voltage drops due to the use of an extension cord or when the voltage rises due to the use of a booster or generator. The number of rotations of the motor is varied according to the voltage. Thus, in the motor drive device in which the rotation speed of the motor greatly fluctuates, the vibration suppressing effect by the balancer is not sufficiently exhibited, and the machine may move due to the vibration during the operation of the machine.

  In addition, in a motor drive device having a user mode such as a silent mode or a rapid mode, noise can be suppressed or a machine can be operated rapidly by changing the rotational speed of the motor. Even in such a motor drive device, since the rotation speed of the motor greatly fluctuates, the vibration suppressing effect by the balancer is not sufficiently exhibited, and the machine may move due to the vibration during the operation of the machine.

  Therefore, the present invention provides a motor drive device capable of suppressing the movement of the machine due to vibration even when vibration that is difficult to be suppressed by a balancer or the like is generated and transmitted to the support leg. The task is to do.

  The present invention has been made to solve the above-described problems, and is characterized by the following.

  The invention according to claim 1 is a motor drive device that drives a drive unit by a motor, and includes a plurality of support legs fixed to the bottom surface of the device body and grounded, and the support legs include an elastic member, A shaft member that fixes the elastic member to the device main body, and at least one of the elastic members is formed asymmetrically with respect to a mounting portion of the shaft member, and the shaft member is arranged in a predetermined direction. It is characterized by comprising a deformation promoting part for making it easier to tilt.

  According to a second aspect of the invention, in addition to the feature of the first aspect of the invention described above, an insertion hole is formed in the elastic member, and the elastic member is formed by the shaft member passing through the insertion hole. It is fixed to the apparatus main body.

  In the invention according to claim 3, in addition to the feature point of the invention according to claim 1 or 2, the shaft member is easily inclined toward the center of gravity of the device body by providing the deformation promoting portion. It is characterized by.

  According to a fourth aspect of the present invention, in addition to the feature of the invention according to any one of the first to third aspects, the deformation promoting portion is formed by thinning a part of the elastic member. It is characterized by being.

  The invention described in claim 5 is characterized in that, in addition to the feature of the invention described in claim 4, the deformation promoting portion is a circumferential groove arranged concentrically with the insertion hole.

  According to a sixth aspect of the present invention, in addition to the features of the above-described fourth or fifth aspect, the elastic member includes an upper portion provided with the deformation promoting portion and a grounding portion that contacts the ground. A lower portion and a middle portion provided between the upper portion and the lower portion, wherein the middle portion is formed thicker than the upper portion and the lower portion.

  The invention according to claim 7 is characterized in that, in addition to the features of the invention according to any one of claims 1 to 6, the device main body and the elastic member are interposed between the device main body and the elastic member. A gap forming portion for generating a gap between the members is provided.

  The invention according to claim 1 is as described above, and at least one of the elastic members is formed asymmetrically with respect to the mounting portion of the shaft member, so that the shaft member can be easily tilted in a predetermined direction. Since the deformation promoting portion is provided, when vibration is generated and transmitted to the support leg portion, the elastic member is deformed and the shaft member is tilted, whereby the vibration transmission direction can be controlled. That is, the machine can be prevented from moving due to vibration, and the problem of soiling or scratching the ground plane is unlikely to occur. In addition, since the supporting leg part absorbs vibration, vibration transmitted to the floor is reduced, so that noise and the like can be reduced.

  Further, the invention according to claim 2 is as described above, and an insertion hole is formed in the elastic member, and the elastic member is fixed to the device main body by the shaft member penetrating the insertion hole. The generated vibration can be received by the insertion hole, and the elastic member can be deformed to tilt the shaft member to absorb the vibration.

  Further, the invention according to claim 3 is as described above, and the shaft member is easily inclined toward the center of gravity of the device main body by providing the deformation promoting portion. The member tilts toward the center of gravity of the device body. According to such a structure, even when a restoring force is generated after the elastic member is deformed, the restoring force is generated inwardly (in the direction of the center of gravity of the device body), so it does not work in the direction of moving the machine. It will work in such a way as to stretch the machine so as not to move it.

  Further, the invention according to claim 4 is as described above, and the deformation promoting portion is formed by making a part of the elastic member thin. Therefore, the effect as described above is achieved with a simple structure. Can be obtained.

  Further, the invention according to claim 5 is as described above, and the deformation promoting portion is a circumferential groove disposed concentrically with the insertion hole, so that the shaft member can be smoothly inclined along the circumferential groove. be able to.

  The invention according to claim 6 is as described above, and the elastic member includes an upper part provided with the deformation promoting part, a lower part provided with a grounding part that contacts the ground, the upper part and the lower part, And the middle part is formed to be thicker than the upper part and the lower part, so that vibration can be efficiently absorbed by deforming the upper part and the lower part. Further, high-order vibrations can be effectively absorbed by the thin portion while ensuring strength by the thick portion and maintaining shock absorbing performance against impacts such as dropping.

  The invention according to claim 7 is as described above, and a gap forming portion is provided between the device main body and the elastic member so as to generate a gap between the device main body and the elastic member. Since it is provided, when an impact occurs in the vertical direction due to a machine drop or the like, the impact can be mitigated by compressing the gap and receiving the device main body with an elastic member.

It is the (a) side view and (b) bottom view of the air compressor which removed the cover. It is an enlarged view of A part shown in FIG.1 (b). It is the (a) BB sectional view shown in FIG. 2, (b) CC sectional view. It is the (a) perspective view and (b) top view of an elastic member. It is sectional drawing of an air compressor. It is sectional drawing which shows a mode that an elastic member elastically deforms. It is (a) top view of the elastic member which concerns on the modification 1, (b) DD sectional drawing. It is (a) top view of the elastic member which concerns on the modification 2, (b) EE sectional drawing, (c) FF sectional drawing, (d) Front view. It is (a) top view of the elastic member which concerns on the modification 3, (b) GG sectional drawing.

  The embodiment of the present invention will be described with reference to the drawings, taking an air compressor 10 as a motor drive device as an example.

  As shown in FIG. 1, the air compressor 10 according to the present embodiment includes an electric motor 12, a fan 13 that is coupled to a drive shaft of the motor 12 to generate cooling air, and a compressor that is driven by the motor 12. (Drive unit), a tank 16 for storing high-pressure compressed air generated by the compression unit, and a plurality of support legs 20 attached to the lower part of the tank 16.

The air compressor 10 according to this embodiment is a multistage compressor including a plurality of compression units that generate compressed air. Specifically, the low-pressure side primary compression mechanism 14 and the high-pressure side secondary compression mechanism 15 are provided. And. The primary compression mechanism 14 and the secondary compression mechanism 15 are horizontally disposed so as to face each other via a crankcase, and each includes a piston cylinder that reciprocates by a motor 12, and compresses air by piston movement. . Specifically, the air taken in from the outside is compressed by reciprocating the piston of the primary compression mechanism 14, the compressed air is sent to the cylinder of the secondary compression mechanism 15, and the piston of the secondary compression mechanism 15 is reciprocated. And compress further. The compressed air thus pressurized to a high pressure is sent to and stored in the tank 16, and is sent out to various devices and tools as necessary.
The motor 12 is, for example, a DC brushless motor and is inverter-controlled.

  The primary compression mechanism 14 and the secondary compression mechanism 15 are arranged so that the direction in which each piston reciprocates and the longitudinal direction of the tank 16 coincide with each other, and are connected to the primary compression mechanism 14 and the secondary compression mechanism 15. The motor 12 thus fixed is fixed to the tank 16 via a buffer member.

  The device main body 11 of the air compressor 10 is configured by arranging devices such as a motor 12 and a compression unit on the tank 16 described above. Further, support legs 20 are provided on the lower surface of the tank 16 so that the air compressor 10 can be placed on a floor surface or the like.

  The support legs 20 are fixed to the bottom surface of the apparatus main body 11 and grounded. In this embodiment, as shown in FIG. 1, a total of four support legs 20 are provided at almost four corners of the lower surface of the tank 16. It is fixed. As shown in FIG. 3, a fixed plate 16a is fixed to the lower surface of the tank 16 by welding or the like, and a support leg 20 is attached to the fixed plate 16a.

  The support leg 20 includes an elastic member 21 having an insertion hole 21d, a collar member 22 attached to the insertion hole 21d, and the device main body 11 (specifically, a fixing plate 16a on the lower surface of the tank 16) through the collar member 22. And a washer 24 for preventing the shaft member 23 from coming off.

  The elastic member 21 according to the present embodiment is formed of an elastic material such as rubber, and as shown in FIGS. 3 and 4, an upper part 21a provided with a deformation promoting part 21e and a grounding part 21h that contacts the ground. A lower portion 21c provided with a central portion 21b provided between the upper portion 21a and the lower portion 21c, and a support portion 21i formed to rise further above the upper portion 21a.

  As shown in FIG. 4B, the elastic member 21 is formed in a substantially square shape in plan view, and is fixed to the device main body 11 so that one side of the substantially square faces the inner side (the center of gravity of the device main body 11). Is done.

  The support portion 21 i of the elastic member 21 is a U-shaped wall portion formed in a plan view so that the upper end portion is along the lower surface of the tank 16. The support portion 21i is formed so that the back wall portion 21j disposed on the opposite side (outside) of the center of gravity of the device body 11 is formed highest, and the side wall portions 21k extend from both ends of the highest formed back wall portion 21j. It has come to be. The upper surface of the side wall portion 21k is inclined downward toward the end portion.

  An insertion hole 21d to which the collar member 22 can be attached is formed in the upper portion 21a of the elastic member 21 so as to penetrate therethrough in the vertical direction. In addition, an arc-shaped circumferential groove is disposed on the upper surface of the upper portion 21a concentrically with the insertion hole 21d, and a deformation promoting portion 21e is formed by the circumferential groove. The deformation promoting portion 21e is for facilitating the deformation of the elastic member 21 in a predetermined direction, for example, for facilitating the inclination of the shaft member 23 in the predetermined direction. That is, when the circumferential groove is provided, a part of the elastic member 21 is thin, and when a force is applied to the collar member 22 and the shaft member 23 inserted through the insertion hole 21d, the collar member 22 and The shaft member 23 is formed so as to easily tilt in the direction of the deformation promoting portion 21e.

  In addition, as shown in FIG. 4, this deformation | transformation promotion part 21e is provided in the other side of the back wall part 21j, in other words, the gravity center side (inner side) of the apparatus main body 11. As shown in FIG. For this reason, the elastic member 21 is formed asymmetrically when viewed from the insertion hole 21d. That is, when the center of gravity side (inner side) and the opposite center of gravity side (outer side) are compared with each other when viewed from the insertion hole 21d, they are asymmetric depending on the presence or absence of the deformation promoting portion 21e. By forming the deformation promoting portion 21e asymmetrically in this way, the collar member 22 and the shaft member 23 are easily inclined only in a predetermined direction, so that the movement when the elastic member 21 is elastically deformed can be controlled. Specifically, the shaft member 23 can be easily tilted toward the center of gravity of the device main body 11 by providing the deformation promoting portion 21 e on the center of gravity (inside) of the device main body 11.

As shown in FIG. 3, the middle part 21b of the elastic member 21 is formed thicker than the upper part 21a and the lower part 21c. Thereby, while giving rigidity to the middle part 21b, the upper part 21a and the lower part 21c become easy to deform | transform, and vibration can be efficiently absorbed by the upper part 21a and the lower part 21c.
As shown in FIG. 3, the lower portion 21c of the elastic member 21 is grounded to the floor surface or the like by a cylindrical grounding portion 21h.

  The collar member 22 is a cylindrical member that is formed of metal or the like and supports the shaft member 23. As shown in FIG. 3 and the like, the collar member 22 is inserted into the insertion portion 21d of the elastic member 21 and the insertion portion 21a. And a flange portion 22b that engages with the upper edge of the hole 21d. The flange portion 22b is sandwiched and interposed between the device main body 11 (fixed plate 16a) and the elastic member 21, thereby generating a gap G between the device main body 11 (fixed plate 16a) and the elastic member 21. It is provided as a gap forming part. The gap G formed by the flange portion 22b is provided to alleviate this impact when an impact in the vertical direction such as the air compressor 10 dropping is applied.

  The shaft member 23 is, for example, a screw that is screwed into the fixing plate 16a, and is screwed through the collar member 22 attached to the insertion hole 21d of the elastic member 21, so that the support leg 20 is attached to the device body. 11 is fixed integrally. In the present embodiment, the shaft member 23 is inserted and attached from the lower opening of the insertion hole 21d. A recess 21l that accommodates the head 23a of the shaft member 23 is formed in the lower portion of the insertion hole 21d. As described above, the support leg 20 and the device main body 11 are connected via the shaft member 23, and vibration generated in the device main body 11 is transmitted to the support leg 20 via the shaft member 23. The

  In the structure according to the present embodiment, when vibration is generated in the device main body 11 and the support leg 20 receives a load due to this vibration, as shown in FIG. 6, the collar member 22 and the shaft member 23 are directed in the direction of the deformation promoting portion 21e. Tilts. By acting in this way, the restoring force of the elastic member 21 is directed toward the center of gravity of the device main body 11.

  In the prior art (see, for example, FIG. 4 of Patent Document 1), when a force to move the machine (force that pushes the device main body 11 in the direction opposite to the center of gravity, that is, outward) is applied, In response, the upper part of the rubber foot is elastically deformed outward.

  The rubber foot whose upper part is elastically deformed outwardly tries to return to its original shape by the restoring force when the force to move is released, but the upper part is not restored inward and the tip of the rubber foot (contact In some cases, only the ground) may be restored to the outside. In this case, the grounding position is gradually shifted, so that the machine may move.

  In this regard, according to the present embodiment, as shown in FIG. 6, the shaft member 23 is deformed so as to tilt toward the inside of the device body 11 even when a force pushing the device body 11 in the direction opposite to the center of gravity, that is, the outside is applied. To do. Therefore, the restoring force generated in the elastic member 21 at the timing when the load is released acts in a direction in which the shaft member 23 is pushed obliquely inward. In other words, the restoring force of the elastic member 21 does not work in the direction in which the machine is moved, but rather works in a form of stretching so as not to move the machine. In this way, the machine is difficult to move.

  For this reason, it is possible to prevent the machine from moving when vibration is generated, and the problem of soiling or scratching the ground plane is unlikely to occur. Moreover, since the support leg part 20 absorbs vibration, the propagation vibration to the floor is reduced, so that noise and the like can also be reduced.

  Further, when considering the load applied to the support leg 20 from another viewpoint, as shown in FIG. 5, when the device main body 11 is viewed in a cross section in the direction of the motor shaft 12 a, the primary compression mechanism 14 that is an excitation source and Since the secondary compression mechanism 15 is located at a position shifted from the position of the center of gravity, a moment around the center of gravity is transmitted to the support leg 20. For this reason, when a load is applied so that the left support leg 20 in FIG. 5 is compressed, the load is applied from the outside to the inside of the device main body 11.

  At this time, when the deformation promoting portion 21e is not provided (for example, when a conventional structure as shown in FIG. 6 of Patent Document 1 is used), the elastic member 21 has the shaft member 23 inclined to the outside of the device body 11. To absorb the load. At the timing when the load is released, a force to move the device main body 11 to the outside acts and the restoring force of the elastically deformable support leg 20 also moves to the outside, so that the force to move the machine to the outside growing. Furthermore, since the load in the vertical direction is also reduced to coincide with the timing at which the friction is reduced, the device main body 11 moves outward (to the left in the figure).

  In this regard, according to the present embodiment, as shown in FIG. 6, the shaft member 23 is deformed so as to tilt toward the inside of the device body 11 even when a force pushing the device body 11 toward the center of gravity, that is, the inside is applied. . Therefore, even if the restoring force of the elastic member 21 is generated at the timing when the load is released, the restoring force acts in a direction to push the shaft member 23 obliquely inward. That is, the restoring force of the elastic member 21 does not work in the direction in which the machine is moved, but rather works so as to be stretched so as not to move the machine. In this way, the machine is difficult to move.

  Moreover, since the deformation | transformation acceleration | stimulation part 21e is formed by making a part of elastic member 21 thin, it can acquire the above effects with a simple structure.

  Further, since the deformation promoting portion 21e is a circumferential groove disposed concentrically with the insertion hole 21d, the shaft member 23 can be smoothly inclined along the circumferential groove.

  The elastic member 21 includes an upper part 21a provided with a deformation promoting part 21e, a lower part 21c provided with a grounding part 21h that contacts the ground, and a middle part 21b provided between the upper part 21a and the lower part 21c. Since the middle portion 21b is formed thicker than the upper portion 21a and the lower portion 21c, vibration can be efficiently absorbed by deforming the upper portion 21a and the lower portion 21c.

  Further, the collar member 22 includes a flange portion 22b that engages with the upper end periphery of the insertion hole 21d, and the flange portion 22b is interposed between the device main body 11 and the elastic member 21, so that the device main body 11 and the elastic member 21 are interposed. Since a gap G is formed between them, if an impact occurs in the vertical direction due to a machine drop or the like, the gap G is compressed and the elastic member 21 receives the device body 11 to mitigate the impact. Can do.

  In the above-described embodiment, the flange portion 22b of the collar member 22 is interposed between the apparatus main body 11 and the elastic member 21, and the gap G is generated by the flange portion 22b. Instead of using it, a protrusion may be provided on the fixing plate 16a or the elastic member 21, and the gap G may be provided so as to be in partial contact.

  In the above-described embodiment, the deformation promoting portion 21e is provided on the elastic member 21 in all the support legs 20, but not limited to this, the deformation promoting portion 21e is provided only on a part of the elastic members 21. You may do it. For example, the deformation promoting portion 21e may be provided only on the elastic member 21 provided in a direction that is easy to move (such as a position farthest from the center of gravity) according to the center of gravity balance of the machine.

  Moreover, the aspect of the deformation | transformation promotion part 21e is not restricted to the thing disclosed in above-described embodiment, Various forms can be considered. For example, as shown in FIG. 7, the circumferential groove of the deformation promoting portion 21e may be extended so as to reach the recess 21l. Further, as shown in FIG. 8, the deformation promoting portion 21f may be formed by a horizontal slit. Moreover, as shown in FIG. 9, the insertion hole 21d may be provided at a position biased toward the opposite center of gravity of the device body 11, thereby forming the deformation promoting portion 21g. In addition, instead of forming the deformation promoting portion 21e by removing the meat, a similar effect can be obtained by forming the deformation promoting portion by partially increasing the strength by adding a rib or the like. .

  In the above-described embodiment, the shaft member 23 is passed through the elastic member 21 and the support leg 20 is fixed to the device body 11. However, the present invention is not limited to this, and the shaft member 23 is integrated with the elastic member 21. It may be formed and fixed to the device main body 11, or the support leg portion 20 may be formed so that a part of the elastic member 21 forms a coupling portion with the main body.

10 Air compressor (motor drive equipment)
DESCRIPTION OF SYMBOLS 11 Apparatus main body 12 Motor 12a Motor shaft 13 Fan 14 Primary compression mechanism (drive part)
15 Secondary compression mechanism (drive unit)
16 tank 16a fixing plate 20 support leg 21 elastic member 21a upper part 21b middle part 21c lower part 21d insertion hole 21e, 21f, 21g deformation promotion part 21h grounding part 21i support part 21j back wall part 21k side wall part 21l concave part 22 color member 22a cylinder part 22b Flange part (gap forming part)
23 Shaft member 23a Head 24 Washer G Gap

Claims (7)

A motor drive device for driving a drive unit by a motor,
A plurality of support legs fixed to the bottom of the device body and grounded,
The support leg includes an elastic member, and a shaft member that fixes the elastic member to the device main body.
At least one of the elastic members is formed asymmetrically with respect to a mounting portion of the shaft member, and includes a deformation promoting portion for easily tilting the shaft member in a predetermined direction. Motor drive equipment.   The motor driving device according to claim 1, wherein an insertion hole is formed in the elastic member, and the elastic member is fixed to the device main body by the shaft member penetrating the insertion hole.   3. The motor-driven device according to claim 1, wherein the shaft member is easily inclined toward the center of gravity of the device main body by providing the deformation promoting portion.   The motor driving device according to claim 1, wherein the deformation promoting portion is formed by thinning a part of the elastic member.   The motor driving device according to claim 4, wherein the deformation promoting portion is a circumferential groove disposed concentrically with the insertion hole.   The elastic member includes an upper part provided with the deformation promoting part, a lower part provided with a grounding part that contacts the ground, and a middle part provided between the upper part and the lower part. 6. The motor driving device according to claim 4, wherein the motor driving device is formed thicker than the upper portion and the lower portion.   The gap forming part for creating a gap between the device main body and the elastic member by being interposed between the device main body and the elastic member is provided. The motor drive device according to item 1.

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