JP2018040423A - gear - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gear capable of preventing occurrence of backlash in the gear, preventing increase of the number of components, and preventing occurrence of rotation delay at an annular gear part due to rotation of a boss part.SOLUTION: A gear has: a boss part configured to mount and fix a rotational shaft; an annular gear part on an outer diameter side of which a plurality of tooth profiles are continuously formed; and a rib part configured to couple the outer diameter side of the boss part and an inner diameter side of the annular gear. The rib part includes such a curve shape that the rib part can be bent only in a radial direction.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a gear.

  Conventionally, in a gear that transmits power by meshing with another gear or by a belt wound around the gear, in order to remove backlash generated in the gear, for example, two gear portions are provided with springs. It is known that a single gear is configured to be connected through the two.

  However, the gear configured as described above has a problem in that the number of component parts increases, so that the assembly work is complicated and the cost is increased.

  Further, as another example of a gear for removing backlash, a gear disclosed in Japanese Patent Application Laid-Open No. 8-233071 is known.

  The gear disclosed in Japanese Patent Application Laid-Open No. 8-233071 is a curve in which a boss portion for mounting and fixing a rotating shaft and an annular gear portion having a plurality of tooth shapes are curved in a plane perpendicular to the rotating shaft. A plurality of elastically deformable rib portions having a shape are connected to each other. For this reason, according to this gear, the number of components is reduced, the assembling work is simplified, and the cost is not increased.

  However, according to the gear disclosed in the above-mentioned JP-A-8-233071, when the boss portion of the gear is rotated by the rotating shaft, the deformation of the rib portion in the rotating direction is promoted along with the rotation. There is a problem that the followability of the rotation of the annular gear portion accompanying the rotation of the boss portion is inferior, and the rotation of the annular gear portion accompanying the rotation of the boss portion is delayed.

JP-A-8-233071

  The present invention has been made in view of the various problems of the conventional techniques as described above, and the object of the present invention is to prevent the occurrence of backlash in the gear and reduce the number of components. An object of the present invention is to provide a gear that does not cause an increase and does not cause a delay in the rotation of the annular gear portion accompanying the rotation of the boss portion.

  In order to achieve the above object, a gear according to the present invention flexes only a radial direction between a boss portion to which a rotating shaft is attached and an annular gear portion in which a plurality of teeth are continuously formed on the outer diameter side. It is connected by a rib part that can be removed.

  That is, the gear according to the present invention is a gear, and includes a boss portion on which a rotating shaft is mounted and fixed, an annular gear portion in which a plurality of tooth forms are continuously formed on the outer diameter side, and an outer diameter of the boss portion. And a rib portion that connects the inner diameter side of the annular gear, and the rib portion has a curved shape that allows the rib portion to bend only in the radial direction.

  The gear according to the present invention is the gear according to the present invention described above, wherein the curved shape of the rib portion includes a convex portion protruding in the axial direction of the rotating shaft.

  The gear according to the present invention is the gear according to the present invention described above, wherein the rib portion is a plate-like body, and the width of the surface extending in the rotation direction of the gear is in the axial direction of the rotation shaft. It is wider than the width of the surface on the extending side.

  Further, the gear according to the present invention is the above-described gear according to the present invention, wherein the rib portion includes a first rib in which the convex portion projects on one side in the axial direction of the rotating shaft and the convex portion is an axis of the rotating shaft. A second rib projecting on the other side of the direction, and the first rib and the second rib are alternately arranged.

  In the gear according to the present invention, the rib portion and the annular gear portion are formed of resin in the gear according to the present invention.

  The gear according to the present invention is the gear according to the present invention described above, wherein the boss portion, the rib portion, and the annular gear portion are formed of resin.

  Since the present invention is configured as described above, it prevents the occurrence of backlash in the gear, does not increase the number of components, and the annular gear portion according to the rotation of the boss portion. This provides an excellent effect of not causing a delay in rotation.

FIG. 1 is an explanatory front perspective view showing a first embodiment of a gear according to the present invention. FIG. 2 is a plan view of the gear shown in FIG. Fig.3 (a) is explanatory drawing which shows typically the cross section by the BB line of FIG. FIG. 3B is an explanatory view schematically showing a cross section taken along the line C-C in FIG. FIG. 4 is an explanatory front perspective view showing a second embodiment of the gear according to the present invention. FIG. 5 is an explanatory diagram showing a cross section taken along line DD of FIG.

  Hereinafter, an example of an embodiment of a gear according to the present invention will be described in detail with reference to the accompanying drawings.

  A first embodiment of a gear according to the present invention will be described with reference to FIGS. 1 to 3.

  The gear 10 includes a boss portion 12 to which the rotary shaft 100 is attached and fixed, an annular gear portion 14 in which a plurality of tooth profiles 14a are continuously formed on the outer diameter surface side, and an outer diameter surface 12a of the boss portion 12. A plurality of rib portions 16 are provided so as to connect the inner diameter surface 14 b of the annular gear portion 14.

  The rib portion 16 has a curved shape so that it can be bent only in the radial direction, and the entire circumference of the inner diameter surface 14 c of the annular gear portion 14 from the entire circumference surface of the outer diameter surface 12 a of the boss portion 12. A plurality of elements are arranged radially toward the surface.

  In the gear 10, at least the annular gear portion 14 and the rib portion 16 are formed of an elastically deformable material, for example, resin. When configuring the gear 10, the boss portion 12, the annular gear portion 14, and the rib portion 16 may be integrally formed of an elastically deformable material such as a resin.

  Next, the rib portion 16 will be described in detail. The rib portion 16 includes one first rib 16a and one second rib 16b each having a convex shape opposite to the curved shape that curves in the axial direction of the rotating shaft 100. They are arranged alternately.

  Specifically, the rib portion 16 includes a first rib 16a having a curved shape that is curved so as to have a convex shape on one side in the axial direction of the rotating shaft 100 (for example, the upper side in FIG. 1). The second rib 16b has a curved shape that is curved so as to have a convex shape on the other side in the axial direction of the rotating shaft (for example, the lower side in FIG. 1).

  The first ribs 16 a and the second ribs 16 b are alternately arranged so as to extend radially from the outer diameter surface 12 a of the boss portion 12 toward the inner diameter surface 14 b of the annular gear portion 14.

  The first rib 16a and the second rib 16b are plate-like bodies, and the width T1 of the surface on the side extending in the rotation direction of the gear 10 is the width T2 of the surface on the side extending in the axial direction of the rotation shaft 100. The dimension is set so as to be wider (see FIG. 3B).

  In the above configuration, when the gear 10 is used, for example, in a gear train such as a gear reduction mechanism, the first rib 16a and the second rib 16b constituting the rib portion 16 of the gear 10 are radially deformed by elastic deformation. Since it bends, the diameter of the annular gear portion 14 can be changed to eliminate backlash.

  Further, since the annular gear portion 14 becomes movable with respect to the boss portion 12 through the elastically deforming rib portions 16 (first rib 16a and second rib 16b), external factors (vibration, impact, vibration) Can be relaxed.

  Furthermore, even if the gear 10 is rotated using the rotary shaft 100 as a drive shaft, the first rib 16a and the second rib 16b that constitute the rib portion 16 have a curved shape that bends only in the radial direction. Since there is little deformation of the rib portion 16 in the rotation direction accompanying the rotation, it is possible to suppress a delay in the rotation of the annular gear portion 14 accompanying the rotation of the boss portion 12.

  Further, the first rib 16a and the second rib 16b constituting the rib portion 16 are such that the width T1 of the surface extending in the direction orthogonal to the axial direction of the rotating shaft 100 extends in the axial direction of the rotating shaft. Therefore, the deformation of the rib portion 16 (the first rib 16a and the second rib 16b) in the rotation direction accompanying the rotation is further suppressed. Further, a delay in the rotation of the annular gear portion 14 accompanying the rotation of the boss portion 12 is further suppressed.

  Furthermore, in the gear 10, since the first ribs 16 a and the second ribs 16 b whose convex shapes in the curved shape are opposite to each other as the rib portions 16 are alternately arranged, the rib portions 16 are deformed when the rib portions 16 are deformed. The balance of the rotation of the gear 10 can be maintained.

  Next, a second embodiment of the gear according to the present invention will be described with reference to FIGS.

  The gear 20 is different from the gear 10 only in that the rib portion 16 is configured only by the first rib 16a.

  That is, the gear 20 corresponds to the gear 10 in which the second rib 16b is replaced with the first rib 16a.

  Since the curved shape of the rib portion 16 of the gear 20 is uniform, it is easier to manufacture a mold or the like used for manufacturing compared to the gear 10, and the manufacturing cost can be reduced.

  As described above, according to the gears 10 and 20, when the gears 10 and 20 are used in a gear train used for positioning control or the like, it is possible to perform extremely accurate positioning without backlash and without rotation delay. become.

  The embodiment described above may be modified as shown in the following (1) to (5).

  (1) In the above-described embodiment, the rib portion 16 is provided with a convex shape protruding in the axial direction of the rotating shaft 100 in order to bend the rib portion 16 only in the radial direction. Of course, it is not possible. For example, a bellows portion that is repeatedly folded back in one axial direction and the other direction may be formed in the rib portion, and the rib portion may be bent only in the radial direction by the bellows portion.

  (2) In the above-described embodiment, the specific description of the number of the first ribs 16a and the second ribs 16b constituting the rib portion 16 is omitted, but the first ribs 16a and the second ribs 16b There is no limit to the number of the gears, and it may be determined appropriately according to the design conditions such as the usage status of the gears 10 and 20.

  (3) In the above-described embodiment, the first ribs 16a and the second ribs 16b constituting the rib portion 16 of the gear 10 are alternately arranged one by one. However, the present invention is not limited to this. It is. That is, two or more first ribs 16a and second ribs 16b may be alternately arranged, and the number of the first ribs 16a and the second ribs 16b arranged alternately is different. May be.

  (4) In the above-described embodiment, the first rib 16a and the second rib 16b constituting the rib portion 16 in the gear 10 are alternately positioned without overlapping in the rotation shaft 100 direction. Of course, the present invention is not limited to this. In other words, the first rib 16 a and the second rib 16 b constituting the rib portion 16 may be arranged so as to overlap each other in the axial direction of the rotating shaft 100.

  (5) You may make it combine suitably the embodiment shown above and the modification shown in said (1) thru | or (4).

  The present invention is suitable for use in a gear train such as a gear reduction mechanism.

  DESCRIPTION OF SYMBOLS 10 Gear, 12 Boss part, 12a Outer diameter surface, 14 Annular gear part, 14a Tooth profile, 14b Inner diameter surface, 16 Rib part, 16a 1st rib, 16b 2nd rib, 20 Gear, 100 Rotating shaft

Claims (6)

A gear,
A boss part to which the rotation shaft is attached and fixed
An annular gear portion in which a plurality of teeth are continuously formed on the outer diameter side;
A rib portion connecting the outer diameter side of the boss portion and the inner diameter side of the annular gear,
The said rib part was equipped with the curved shape which the said rib part can bend only to radial direction. The gearwheel characterized by the above-mentioned. The gear according to claim 1, wherein
The curved shape of the rib portion includes a convex portion protruding in the axial direction of the rotating shaft. The gear according to any one of claims 1 and 2,
The rib portion is a plate-like body, and the width of the surface on the side extending in the rotation direction of the gear is wider than the width of the surface on the side extending in the axial direction of the rotation shaft. gear. The gear according to any one of claims 1, 2, or 3,
The rib portion includes a first rib in which the convex portion protrudes on one side in the axial direction of the rotary shaft, and a second rib in which the convex portion protrudes on the other side in the axial direction of the rotary shaft,
The gears, wherein the first ribs and the second ribs are alternately arranged. The gear according to any one of claims 1, 2, 3 or 4.
The said rib part and the said annular gear part were formed with resin. The gear characterized by the above-mentioned. The gear according to any one of claims 1, 2, 3 or 4.
The boss portion, the rib portion, and the annular gear portion are made of resin.

Images