JP3587553B2 - Vibration prevention device - Google Patents

Description

[0001]
[Industrial applications]
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration generation preventing device to which predetermined technical improvements have been added so that, when a gear transmission mechanism is driven by a drive source such as a motor, vibration is not generated from the gear transmission mechanism.
[0002]
[Prior art]
Conventionally, various vibration generation preventing devices have been developed. For example, in FIG. 4, for example, in FIG. 4, a motor 7 fixed on the main body 3 by fastening the mounting flange 1 to the main body 3 with a fixing screw 2, A vibration generation preventing device is applied to a drive system including a drive gear 11 connected to the motor 7 via a drive shaft 9 (“Mechanical Design, April 1994, Vol. 38 No. 7 Stepping Motor”). Vibration countermeasures ”).
[0003]
As shown in FIG. 4A, the vibration generation preventing device according to the first conventional example includes an elastic member 5 interposed between the mounting flange 1 and the main body 3. According to such a configuration, the vibration generated by the motor 7 is absorbed and removed in advance by the elastic member 5 and is not transmitted to the main body 3, but is transmitted to the tooth surface of the drive gear 11 via the drive shaft 9. The transmitted vibration cannot be eliminated.
[0004]
As shown in FIG. 4 (b), the vibration prevention device according to the second conventional example includes a disc spring 13 stretched between the mounting flange 1 and the drive gear 11. According to such a configuration, the “play” in the axial direction (that is, the thrust direction) of the drive shaft 9 can be elastically removed by the disc spring 13, and therefore, the vibration transmitted to the tooth surface of the drive gear 11. Can be removed in advance.
[0005]
As shown in FIG. 4C, the vibration generator according to the third conventional example is provided on a drive gear 11 itself, and the drive gear 11 is a disk-shaped flange portion attached to a drive shaft 9. 11a, an annular elastic member 11b coaxially fitted on the outer peripheral surface of the disc-shaped flange portion 11a, and an annular gear portion 11c coaxially fitted on the outer peripheral surface of the annular elastic member 11b. Have been. According to such a configuration, the vibration of the motor 7 transmitted to the drive shaft 9 is absorbed and removed in advance by the annular elastic member 11b, and is not transmitted to the annular gear portion 11c.
[0006]
[Problems to be solved by the invention]
However, in the first conventional example, the entire drive system becomes unstable due to the elastic member 5, the positions of the tooth surfaces of the drive gear 11 vary, and problems such as uneven wear of the tooth surfaces and poor meshing occur. Furthermore, since the vibration transmitted through the tooth surface cannot be removed, there arises a problem that the tooth surfaces collide with each other and noise is generated from the drive gear 11. In particular, in a drive system using a small-diameter gear of the module, poor meshing between the tooth surfaces is one of the major causes of noise generation.
[0007]
In the second conventional example, when the motor 7 is driven, friction occurs between the disc spring 13 and the mounting flange 1 and the driving gear 11, which causes a torque loss of the motor 7.
Although a slight improvement can be achieved by filling grease for friction prevention, the disc spring 13 eventually gives a frictional state again because the pressing force is always applied to the mounting flange 1 and the driving gear 11. Would. In this case, the load on the motor 7 increases, and the motor 7 is required to have an excessive torque or a margin based on temperature change and aging. Therefore, an increase in the cost of the motor 7 and an increase in the running cost are unavoidable. Note that such a problem also occurs when, for example, a coil spring is used instead of the disc spring 13.
[0008]
In the third conventional example, the driving gear 11 becomes unstable due to the annular elastic member 11b, and the tooth surface position of the annular gear portion 11c varies, so that the meshing position accuracy (coaxiality) between the tooth surfaces is kept constant. Becomes difficult. Even if the configuration is such that the coaxiality is ensured, it is not possible to maintain the meshing position accuracy between the tooth surfaces again due to the deterioration with time of the annular elastic member 11b and the like. Further, the third conventional example can secure the noise prevention effect when applied to a relatively large drive gear 11, for example, but on the other hand, when applied to a small-diameter gear having a small module, the elastic force of the annular elastic member 11b can be secured. Is required to be considerably weakened, which further deteriorates the meshing position accuracy.
[0009]
The present invention has been made in order to solve such a problem, and an object of the present invention is to easily generate a vibration in a predetermined drive system without affecting the drive system. It is an object of the present invention to provide a low-cost vibration generation preventing device capable of preventing vibration.
[0010]
[Means for Solving the Problems]
In order to achieve such an object, the vibration generation preventing device of the present invention is
It can be incorporated in a drive system including a drive gear driven by a drive unit fixed to the main body ,
The drive gear is fixed to an output shaft of the drive means,
An elastic member having one end fixed to the main body and a ball housing formed at the other end, extending from the one end along the side surface of the drive gear, and generating an urging force in a direction parallel to an output shaft of the drive means ;
A ball rotatably accommodated at a fixed position in a ball accommodating portion formed at the other end of the elastic member and pressed against the drive gear by the urging force of the elastic member ;
It is characterized by having.
[0011]
[Action]
The vibration generation preventing device of the present invention is incorporated in a drive system, and one end is fixed to the main body, the other end is formed with a ball housing portion , and the output of the drive means of an elastic member extending from the one end along the side surface of the drive gear By a biasing force in a direction parallel to the extending direction of the shaft, a ball rotatably accommodated at a fixed position in a ball accommodating portion formed at the other end of the elastic member is pressed in a point contact state with the drive gear. By doing so, the vibration generated in the driving gear is absorbed and removed by the elastic urging means, and the torque loss of the driving means is eliminated without generating friction between the ball and the driving gear.
[0012]
【Example】
Hereinafter, a vibration generation preventing device according to a first embodiment of the present invention will be described with reference to FIG.
FIG. 1 shows a state in which the vibration generation preventing device of the present embodiment is incorporated in a predetermined drive system.
[0013]
As shown in FIG. 1, the driving system applied to the present embodiment includes a driving means, that is, a motor 27 fixed on the main body 23 by fastening the mounting flange 21 to the main body 23 with a fixing screw 22, A first drive gear 31 connected to the first drive shaft 29 via a first drive shaft 29; and a second drive gear 32 meshed with the first drive gear 31. Note that the second drive gear 32 is connected to a transmission mechanism (not shown) provided in the main body 23 via a second drive shaft 33.
[0014]
The vibration generation preventing device of this embodiment includes an elastic member 25 having one end fastened to the main body 23 by a fixing screw 35 and the other end rotatably provided with a resin ball 37. The resin ball 37 is rotatably accommodated in a conical recess 25 a formed at the other end of the elastic member 25.
[0015]
The elastic member 25 is disposed such that one end thereof extends to a region between the first drive gear 31 and the mounting flange 21.
Due to the elastic force of the elastic member 25, the resin ball 37 in the conical concave portion 25a of the elastic member 25 always faces the front side surface (that is, the side surface facing the mounting flange 21) of the first drive gear 31. It is maintained in a state where it can roll freely on the edge and is pressed in a point contact state.
[0016]
According to such a configuration, the vibration transmitted from the motor 27 to the first drive gear 31 via the first drive shaft 29 is absorbed and removed by the elastic member 25 and the resin ball 37. Is achieved. As a result, it is possible to stably drive the first drive gear 31 at a constant state.
[0017]
In addition, the vibration transmitted to the tooth surface of the first drive gear 31 is also absorbed and removed by the elastic member 25 and the resin ball 37, so that the tooth between the first drive gear 31 and the second drive gear 32 is removed. Poor meshing between the surfaces can be prevented. As a result, it is possible to reduce noise generated when the tooth surfaces collide with each other.
[0018]
Furthermore, since the resin ball 37 is always in rolling contact with the front surface of the first drive gear 31 in a point contact state so as to be freely rotatable, friction between the resin ball 37 and the first drive gear 31 is reduced. It does not occur. As a result, since an unnecessary load is not applied to the motor 27, the torque cross of the motor 27 can be eliminated. Since such a resin ball 37 is pressed against the front surface of the first drive gear 31 while being held and maintained in the conical recess 25a of the elastic member 25, the first drive gear 31 is It does not fall off even if it rotates.
[0019]
Furthermore, even when the vibration generation preventing device of this embodiment is applied to, for example, a small drive system using a small-diameter gear of a small module, the elastic member 25 and the resin ball 37 are adapted to correspond to the size of the small drive system. Since the elastic force of the small drive system can be adjusted easily and appropriately, it is possible to efficiently prevent the vibration of the small drive system and the generation of noise due to poor meshing between the tooth surfaces.
[0020]
Next, a vibration prevention device according to a second embodiment of the present invention will be described with reference to FIG. In the description of this embodiment, the same components as those of the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.
[0021]
The vibration generation preventing device of the present embodiment is provided between the mounting flange 21 and the first drive gear 31, and is provided on the front side surface of the first drive gear 31 (that is, the side surface facing the mounting flange 21). A compression coil spring 39 is provided coaxially around the first drive shaft 29, and is constantly urged toward the mounting flange 21 by the compression coil spring 39, and is coaxial with the first drive shaft 29. A ring-shaped plate 41 slidably provided, and a resin ball 43 which is rolled on the mounting flange 21 and is pressed in a point contact state by the ring-shaped plate 41 receiving the urging force of the compression coil spring 39. ing.
[0022]
On the side surface of the ring-shaped plate 41 (that is, the side surface facing the mounting flange 21), conical concave portions 41a are formed at three equally-divided positions along the circumferential direction. It is rollably and pressure-contacted to the mounting flange 21 in a point contact state while being accommodated in the concave portion 41a.
[0023]
According to such a configuration, in addition to the effect of the first embodiment, a desired urging force can be applied to the first drive gear 31 by appropriately adjusting the urging force of the compression coil spring 39. . As a result, the play (thrust play) in the axial direction of the first drive shaft 29 can be efficiently absorbed and removed, so that the first drive gear 31 can be constantly driven in a stable state. It becomes. In addition, the dimensions of the compression coil spring 39, the ring-shaped plate 41, and the resin ball 43 can be appropriately reduced to desired dimensions, so that the vibration generation preventing device can be reduced in size. Further, when the first drive gear 31 is rotated, the compression coil spring 39, the ring-shaped plate 41 and the resin ball 43 rotate integrally, but the resin ball 43 is formed of a resin member such as polyacetal or nylon. Therefore, there is almost no wear.
[0024]
Next, a vibration generation preventing device according to a third embodiment of the present invention will be described with reference to FIG. In the description of this embodiment, the same components as those of the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.
[0025]
As shown in FIG. 3A, the vibration generation preventing device of the present embodiment is built in the main body 23 and has a back side surface of the first drive gear 31 (that is, the back side surface is opposite to the front side surface). The side edge of the side surface facing the main body 23) is configured to be able to roll and press in a point contact state.
[0026]
That is, the vibration generation preventing device of the present embodiment includes a resin ball 45 that is rollable on the back side surface of the first drive gear 31 and is pressed against the first drive gear 31 in a point contact state. A compression coil spring 47 for applying a pressing force to the back surface of the drive gear 31 and a compression coil spring 47 so that the urging force of the compression coil spring 47 acts on the back surface of the first drive gear 31 via the resin ball 45. And a fixing screw 49 for positioning and fixing in the main body 23.
[0027]
According to such a configuration, in addition to the effect of the first embodiment, it is possible to easily adjust the pressure contact of the resin ball 45 only by adjusting the fixing screw 49. As a result, the play (thrust play) in the axial direction of the first drive shaft 29 can be efficiently absorbed and removed, so that the first drive gear 31 can be constantly driven in a stable state. It becomes. Further, since the vibration prevention device of this embodiment is provided outside the drive system, the device can be easily assembled. Further, since the fixing screw 49 can also be appropriately adjusted from outside of the drive system, it is possible to easily and accurately adjust the pressure contact without inadvertently affecting the drive system during the adjustment. Furthermore, since the vibration prevention device of the present embodiment is configured using generally commercially available components, the manufacturing cost can be reduced.
[0028]
Next, a vibration prevention device according to a fourth embodiment of the present invention will be described with reference to FIG. In the description of this embodiment, the same components as those of the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.
[0029]
As shown in FIG. 3B, the vibration generation preventing device of the present embodiment is disposed between the first drive gear 31 and the mounting flange 21, and connects the first drive gear 31 to the first drive gear. It is configured to be able to be pressed along the axial direction of the shaft 29. In addition, the drawing on the right side of the figure shows a state in which the first drive gear 31 is removed to expose the configuration of the vibration generation preventing device of the present embodiment.
[0030]
That is, in the vibration generation preventing device of the present embodiment, the first drive shaft 29 is rotatably inserted into the center portion thereof and is a region between the mounting flange 21 and the first drive gear 31. One cylindrical member 53 fastened by a fixing screw 51 on the mounting flange 21 so as to protrude in the direction of one drive gear 31, and at a position equally divided into four along the circumferential direction at the peripheral edge of the cylindrical member 53. Four compression springs 55 inserted into the four perforated portions (not particularly shown), and the front surface of the first drive gear 31 (that is, the mounting flange 21) under the urging force of these compression springs 55. And four resin balls 57 that are rollable and press-contacted in a point contact state.
[0031]
According to such a configuration, in addition to the effect of the above-described first embodiment, the axial play (thrust play) of the first drive shaft 29 is caused by the resin ball 57 receiving the urging force of the compression spring 55. Can be efficiently absorbed and removed, so that the first drive gear 31 can be constantly driven in a stable state. In addition, the vibration generation preventing device of this embodiment incorporates the compression spring 55 and the resin ball 57 into the columnar member 53 before connecting the first drive gear 31 to the motor 27 via the first drive shaft 29. Therefore, the efficiency of assembling work of the device can be improved. In addition, since the four resin balls 57 are arranged concentrically around the first drive shaft 29, the first drive gear 31 can be pressed evenly. As a result, it is possible to completely absorb and remove the component force applied not only in the axial direction of the first drive shaft 29 but also in other directions.
[0032]
It is not necessary to provide the resin balls 57 at four equal positions on the columnar member 53, respectively, and the same operation and effect can be obtained even when the resin balls 57 are provided at two equal positions or more.
[0033]
Next, a vibration prevention device according to a fifth embodiment of the present invention will be described with reference to FIG. In the description of this embodiment, the same components as those of the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.
[0034]
As shown in FIG. 3C, the vibration generation preventing device of the present embodiment includes a radial bearing 59 provided in the main body 23 and rotatably supporting the first drive shaft 29 in the radial direction. A compression coil spring 61 is provided between the bearing 59 and the first drive gear 31 and absorbs and removes backlash of the first drive gear 31 in the thrust direction. The main body 23 to which the motor 27 is fastened via the mounting flange 21 is provided with a hole 63 through which the first drive shaft 29 is inserted, and a counterbore 65 into which the radial bearing 59 is press-fitted. I have.
[0035]
According to such a configuration, when the first drive gear 31 is rotated by the motor 27, the first drive gear 31, the compression coil spring 61, and the inner ring 59a of the radial bearing 59 are simultaneously rotated. At this time, the inner ring 59a and the outer ring 59b are in a point contact state. Therefore, no friction is generated between the inner race 59a and the outer race 59b of the radial bearing 59, so that the first drive shaft 29 rotates smoothly and no torque cross of the motor 27 occurs.
[0036]
As described above, according to the present embodiment, in addition to the effects of the first embodiment, the radial bearing 59 and the compression coil spring 61 can efficiently absorb and remove the play in the radial and thrust directions. It is possible to stably drive the first drive gear 31 to a constant state at all times. Further, the compression coil spring 61 contacts the front surface of the first drive gear 31, and the first drive shaft 29 is rotatably supported by the main body 23 via the radial bearing 59 in a point contact state. Regardless of the material of the radial bearing 59, it is possible to prevent the generation of noise due to the vibration of the first drive gear 31. Further, since the commercially available radial bearing 59 is applied to this embodiment, the configuration of the apparatus can be simplified and the manufacturing cost can be reduced.
[0037]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, low cost provided with the elastic urging | biasing means which can be easily integrated in a predetermined drive system, and can prevent generation | occurrence | production of a vibration efficiently without affecting the drive system A vibration prevention device can be provided.
[Brief description of the drawings]
FIG. 1 is a diagram schematically showing a configuration of a vibration generation preventing device according to a first embodiment of the present invention.
FIG. 2 is a partial cross-sectional side view schematically showing a configuration of a vibration generation preventing device according to a second embodiment of the present invention.
FIG. 3A is a cross-sectional view schematically showing a configuration of a vibration generation preventing apparatus according to a third embodiment of the present invention, and FIG. 3B is a cross-sectional view showing a vibration generation apparatus according to a fourth embodiment of the present invention. Sectional drawing which shows roughly the structure of a prevention device, (c) sectional drawing which shows roughly the structure of the vibration generation prevention device which concerns on the 5th Example of this invention.
FIGS. 4A, 4B, and 4C are diagrams each schematically showing a configuration of a drive system to which a conventional vibration prevention device is applied.
[Explanation of symbols]
21: mounting flange, 23: main body, 25: elastic member, 31: first drive gear, 35: fixing screw, 37: resin ball.

Claims (2)

It can be incorporated in a drive system including a drive gear driven by a drive unit fixed to the main body ,
The drive gear is fixed to an output shaft of the drive means,
One end is fixed to the main body and a ball housing is formed at the other end, extends from the one end along the side surface of the drive gear, and generates a biasing force in a direction parallel to the extension direction of the output shaft of the drive means. An elastic member ;
A ball rotatably accommodated at a fixed position in a ball accommodating portion formed at the other end of the elastic member and pressed against the drive gear by the urging force of the elastic member ;
A vibration generation preventing device comprising: The vibration preventing device according to claim 1, wherein the ball is a resin ball .

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