JP4919701B2 - Gear device - Google Patents

Description

  The present invention comprises a pair of gears having a plurality of teeth on the outer peripheral surface and transmitting rotational movement by meshing with the teeth of the counter gear, and the tooth surfaces of the teeth of the counter gears facing each other in the direction of the rotation axis. More specifically, the present invention relates to a gear device that attempts to stabilize rotational accuracy by suppressing the shift of the gear teeth in the direction of the rotation axis during overload.

The conventional gear device is composed of a pair of tapered gears having a plurality of teeth with a tooth tip surface formed in a constant inclined surface in the tooth width direction on the outer peripheral surface, and elastically energizes one of the tapered gears in the direction of the rotation axis. The tooth surface of the lever is pressed against and contacted with the tooth surface of the other tapered gear to eliminate backlash (see, for example, Patent Document 1).
Japanese Patent Laid-Open No. 06-24602 (FIG. 3)

  However, in such a conventional gear device, one taper gear is elastically biased in the direction of the rotation axis so that the tooth surface of the tooth is pressed against the tooth surface of the tooth of the other taper gear. When an external force in the direction of the rotation axis acts on one gear, the one gear may shift in the direction of the rotation axis against the elastic biasing force. In such a gear device, when a large load is applied to the other gear, a stress that causes the teeth to deform is generated in the engaged teeth. At the same time, this stress becomes an external force that shifts the meshed teeth of one gear toward the rotation axis. Therefore, as described above, one gear is displaced in the direction of the rotation axis against the elastic biasing force, and the meshed teeth of the pair of gears may be deformed. For this reason, the meshing state of the teeth is deteriorated, and the rotation accuracy may become unstable. In particular, when such a conventional gear device is used, for example, in an angle sensor that detects a rotation angle, the angle detection accuracy may be deteriorated.

  SUMMARY OF THE INVENTION Accordingly, the present invention addresses such problems, and an object thereof is to provide a gear device that attempts to stabilize rotational accuracy by suppressing the shift of gear teeth in the direction of the rotation axis during overload. And

In order to achieve the above object, a gear device according to the present invention comprises a pair of gears having a plurality of teeth on the outer peripheral surface thereof and transmitting rotational movement by meshing with the teeth of the counter gear, and each of the counter gears facing each other. A gear device in which the tooth surfaces of the teeth of the pair of gears are engaged with each other in the direction of the rotation axis, and the tooth surfaces of the teeth of the pair of gears are in contact with each other in the meshing region where the teeth of the pair of gears are engaged. A shift in the rotational axis direction of the meshed teeth that occurs at the time of overload is opposed to at least one end surface of the meshed teeth in the direction in which the meshed teeth are opposed to each other. It is provided with a regulating member that abuts and regulates.

With such a configuration, a pair of gears having a plurality of teeth on the outer peripheral surface, and transmitting the rotational motion by meshing the opposing mating gears so that the tooth surfaces of the respective teeth face each other in the rotation axis direction teeth in the meshing region meshed in, in the regulating member equipped to face at least one end surface of the teeth meshing at the direction the tooth surfaces of each tooth is butted to each other, meshing occurring during overload A shift in the direction of the rotation axis of the tooth is controlled by contacting at least one end face of the meshed tooth .

  In addition, the regulating member is formed in a substantially U-shaped longitudinal section having a pair of pieces, and is arranged with both end faces of meshed teeth of the pair of gears sandwiched between the pair of pieces. It is. Thereby, the both end surfaces of the teeth engaged with the pair of gears are sandwiched by this piece of the regulating member formed in a substantially U-shaped longitudinal section having a pair of pieces, and the teeth engaged by this piece are inserted. Regulates displacement in the direction of the rotation axis.

  Further, the restricting member is formed in a disk shape having a diameter larger than the diameter of the tooth tip circle of one of the pair of gears, and the one end face of one of the meshed teeth of the other gear The one of the gears is provided on the web surface of the one gear so that the portions projecting outward from the tooth tips of the gears face each other. As a result, a regulating member formed on the web surface of one gear and projecting outward from the tooth tip of one gear is formed in a disk shape having a diameter larger than the tooth tip circular diameter of one gear. The portion is made to face one end face of the meshed tooth of the other gear, and the shift of the tooth meshed by the protruding portion in the direction of the rotation axis is restricted.

  Then, the meshing of the teeth of the pair of gears with the opposing gears is such that at least the tooth surface of one gear is opposed to the tooth surface of the other gear in the rotational axis direction using an elastic member. They are pressed together to meet each other. Thereby, the tooth surface of at least one gear tooth is brought into pressure contact with the tooth surface of the tooth of the other gear in the direction of the rotation axis by the elastic member, and the teeth are engaged.

According to the first aspect of the present invention, the restricting member abuts against at least one end face of the meshed teeth and regulates the displacement in the rotation axis direction that occurs when the teeth meshed with the pair of gears are overloaded. Therefore, the meshing state of the gear teeth does not change even during overload. Therefore, the deformation of the meshing teeth is suppressed, and the rotation accuracy can be stabilized.

  Further, according to the invention according to claim 2, the direction in which the tooth surfaces of the teeth of the pair of gears meshed with each other in the pair of one-side portions of the regulating member formed in a U-shape in the vertical cross section. The deviation of the teeth in the direction of the rotation axis can be regulated.

  Further, according to the invention of claim 3, one gear of the regulating member formed in a disk shape having a diameter larger than the diameter of the tip circle of one gear and provided on the web surface of one gear. It is possible to restrict the shift of the teeth engaged in the portion protruding outward from the tooth tip in the direction of the rotation axis.

  According to the fourth aspect of the present invention, the opposing mating gears can be meshed by being elastically biased so that the tooth surfaces of the teeth face each other in the rotation axis direction, thereby eliminating backlash. be able to.

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a diagram showing an embodiment of a gear device according to the present invention, and is an explanatory diagram of a meshed state of a pair of gears. 2 is a cross-sectional view taken along line AA in FIG. This gear device is composed of a pair of gears having a plurality of teeth on the outer peripheral surface and transmitting rotational movement by meshing with the teeth of the mating gear. And includes one gear G ₁ , the other gear G _2, and a regulating member 1.

One gear G ₁ has a plurality of teeth 2 on its outer peripheral surface and transmits rotational movement by meshing with the teeth (3) of the counterpart gear (G ₂ ), for example, a drive-side gear. Here, in the present invention, the shape of each tooth 2 of _one gear G1 is set to a part of the tooth surface on both sides of each tooth 2 as shown in FIG. A butting step portion 4 that narrows in a tapered shape is formed. In this embodiment, the butting step portion 4 of _one gear G1 is formed in the middle portion of each tooth 2 in the tooth width direction. That is, the tooth thicknesses on both sides differ from each other with the butting step 4 formed in the middle of the teeth 2 in the width direction.

The teeth 2 of the one gear G _1, thereby engaging the teeth 3 and the other gear G ₂ are provided. The gear G ₂ is, intended to transmit rotational motion by meshing with the teeth 2 of the mating gear G ₁ provided with a plurality of teeth 3 on the outer peripheral surface, for example and serves as a driven gear. Here, in the present invention, the shape of each tooth 3 of the other gear G ₂ is formed on a part of the tooth surface on both sides of each tooth 3 with respect to the tooth shape of the standard gear as shown in FIG. A butting step portion 5 that extends in a tapered shape is formed. In this embodiment, the butting step portion 5 of the other gear G ₂ is formed at an intermediate portion in the tooth width direction of each tooth 3. That is, the tooth thicknesses on both sides are made different from each other at the butting step portion 5 formed at the intermediate portion in the tooth width direction of each tooth 3.

Then, as shown in FIG. 2, the _one gear G ₁ and the other gear G ₂ described above are connected to the butting step portions 4 and 5 having the tapered cross-sectional shape of the teeth 2 and 3 as the rotation axes O ₁ , They are meshed so as to abut each other in the O ₂ direction. In this case, since the elastically urged in the rotation axis O ₁ direction of the arrow B direction shown in the figure by the elastic member not shown the one gear G _1, and the butt stepped portion 4 of one gear G ₁ other and a butt stepped portion 5 of the gear G ₂ abut without a gap, it can be reduced or eliminated that the backlash when meshing pair of gears G _1, G ₂ of the teeth 2 and 3 shown in FIG. Note that in the engagement between the gear G ₁ and the gear G _2, teeth other than abutting step portion 4, 5 is adapted to the gap g ₁ is formed without contact, as shown in FIG. 2, The teeth 2 and 3 are prevented from biting into each other.

The restricting member 1 is provided in the meshing region where the gears ₂ and 3 of the _one gear G1 and the other gear G2 are meshed. The regulating member 1 is opposed to at least one of the end surfaces 2a, 2b, 3a, 3b of the teeth 2, 3 meshing with each other in the direction in which the tooth surfaces of the teeth 2, 3 are abutted with each other. provided is, restricts contact with the rotary shaft O _1, O the at least one end face of the teeth 2 and 3 displaced meshing of the _two directions generated during overload teeth 2,3 meshing with each other As shown in FIG. 2, it has a pair of piece portions 6a and 6b opposite to each other, and connects one end portions of the pair of piece portions 6a and 6b to form a substantially U-shaped longitudinal cross section. The teeth 2 and 3 are made of a material having sufficient rigidity to restrict the displacement of the teeth 2 and 3 in the directions of the rotation axes O ₁ and O ₂ . Then, it is disposed to sandwich in one gear _{G 1} and the other end surfaces 2a of the teeth 2, 3 mesh Tsu each other of the gear _{G 2,} 2b, 3a, 3b and a pair of support sections 6a, 6b. Each piece portions 6a of the regulating member 1, 6b and a pair of gears _G 1, the end face 2a of the teeth 2, 3 mesh Tsu each other _{G 2,} 2b, 3a, between the 3b, teeth meshing 2 , 3 is provided with a gap g ₂ that can allow the deviation.

Next, the operation of the gear device configured as described above will be described.
As shown in FIG. 1, one gear G ₁ is displaceably retained on the rotary shaft O ₁ direction by the rotation of the not shown shaft, the other gear G _2, is fixed to an unillustrated rotary shaft Yes. In this case, the other gear G ₂ is not displaced in the direction of the rotation axis O ₂ .

In such a state, the opposing gears G ₁ and G ₂ facing each other and the butting step portions 4 and 5 having a tapered cross section of each tooth 2 and 3 are mutually connected in the directions of the rotation axes O ₁ and O ₂ . They are butt-meshing. Further, one gear G ₁ includes a rotating shaft O ₁ so at the direction of the arrow B direction shown in FIG. 2 is elastically biased, butt stepped portion 4 of one gear G ₁ by an elastic member (not shown) other a butt stepped portion 5 of the gear G ₂ abuts without clearance. Thus, a pair of gears G _1, G _2, each of the teeth 2, 3 engages in the absence of backlash, so that the rotational movement of one gear G ₁ is transmitted to the other gear G _2.

Here, when large load is applied to the other gear G _2, teeth 2,3 of the gears G _1, G ₂ is to deform by an external stress. As a result, one gear G ₁ has a force to shift the gear G ₁ in the direction opposite to the arrow B shown in FIG. 2 in the direction of the rotation axis O ₁ against the elastic biasing force of the elastic member. Works.

However, in the gear device of the present invention, the pair of pieces 6a and 6b of the regulating member 1 are sandwiched between the meshed teeth 2 and 3 of the pair of gears G ₁ and G _{2 in} the directions of the rotation axes O ₁ and O _2. since the arrangement, one end face 2a of the teeth 2 meshing of the gear G ₁ is in contact with the piece portions 6a, the direction opposite to the arrow B shown in FIG. 2 of the teeth 2 meshing of the gear G ₁ The deviation will be regulated. Therefore, the meshing state of the teeth 2 and 3 of the pair of gears G ₁ and G ₂ does not change even when an overload is applied, and deformation of the meshed teeth 2 and 3 is suppressed. Therefore, a stable meshing state is maintained, and the rotational motion is stably transmitted between the gears G ₁ and G ₂ .

FIG. 3 is an explanatory view showing a modification of the regulating member 1. The regulating member 1, as shown in FIG. (B), is formed in a disc shape having a diameter greater than one tip diameter of the gear G _1, one as shown in the diagram (a) the web 9 surface and which is pressed in the direction of arrow B by an elastic member (not shown) at the web surfaces 9, 10 of opposing gear G ₁ is provided on the web surface 10 opposite to the one of the teeth of the gear G ₁ the overhang portion 12 projecting outwardly from the previous 11 to the end surface 3b of the teeth 3 meshing of the other gear G ₂ through a predetermined gap g ₂ is obtained by facing.

In this case, when the overload is applied to the other gear G _2, the one gear G _1, opposite forces are acting on the elastic biasing direction indicated by the arrow B in FIG. 3 (a). However, the regulating member 1 shown in FIG. 3, since the overhang portion 12 that projects outwardly from one gear G ₁ of the tip 11 abuts the end surface 3b of the teeth 3 meshing of the other gear G ₂ The shift in the direction opposite to the arrow B shown in FIG. 4A is restricted in the direction of the rotation axis O ₁ of the tooth 2 engaged with _one gear G ₁ . Therefore, the deformation of the meshed teeth 2 and 3 of the pair of gears G ₁ and G ₂ is suppressed, and the rotational motion is stably transmitted between the gears G ₁ and G ₂ . 3, reference numeral 14 denotes a rotary shaft of one gear G _1, reference numeral 15 denotes a rotational shaft of the other gear G _2.

Incidentally, the regulating member 1 shown in FIG. 3 is not limited to those provided on one of the web surfaces of the gear G ₁ is elastically biased, may be provided on the other of the web surface of the gear G _2. In this case, the regulating member 1 may be provided on the web surface 13 on the same side as the web surface 9 pressed by the elastic member of the _one gear G1.

In the above description, the case where the butting step portions 4 and 5 having a tapered cross-sectional shape are provided in the middle portion in the tooth width direction of the teeth 2 and 3 of the pair of gears G ₁ and G ₂ has been described. the present invention is not limited thereto, abutting step portion 4 and 5, one end face 2a of the tooth width direction of the gears _G 1, each tooth of _{G 2} 2,3, 3a or 2b, be formed near 3b Good.

In addition, the restriction member 1 described above is not limited to one that is applied to a gear device that is a combination of a pair of gears G ₁ and G _{2 in} which the teeth 2 and 3 are each provided with the butt step portions 4 and 5 having a tapered cross section. Alternatively, a combination of tapered gears may be used, and the backlash may be generated by elastically energizing in the direction of the rotation axis and bringing the tooth surfaces of one gear into contact with the tooth surfaces of the other gear. The present invention can be applied to any gear device that eliminates the above.

Further, in this embodiment, a case has been described in which one gear G ₁ is being elastically urged to the rotary shaft O ₁ direction, the present invention is not limited to this, both gears G _1, G ₂ is the rotation axis It may be elastically biased in opposite directions in the direction.

The gear device of the present invention is not limited to thereby transmit a rotational motion meshing pair of gears G _1, G ₂ of the teeth 2, 3, the pair via the idle gear between the gear G _1, G ₂ The rotary motion may be transmitted.

It is a figure which shows embodiment of the gear apparatus by this invention, and is explanatory drawing of the meshing state of a pair of gears. It is the sectional view on the AA line of FIG. It is explanatory drawing which shows the modification of the control member of the gear apparatus by this invention, (a) is a figure which shows the meshing state of a pair of gear, (b) is C arrow directional view of (a).

Explanation of symbols

G ₁ ... One gear G ₂ ... The other gear 1 ... Restriction member 2 ... One gear tooth 2a, 2b ... One gear tooth end face 3 ... The other gear tooth 3a, 3b ... The other gear tooth End surfaces 6a, 6b ... one part of the regulating member 9, 10, 13 ... web surface 11 ... tooth tip 12 ... overhanging part of the regulating member

Claims (4)

It consists of a pair of gears that have a plurality of teeth on the outer peripheral surface and transmit rotational movement by meshing with the teeth of the mating gear, and the tooth surfaces of each tooth are butted against each other in the direction of the rotation axis. A gear device engaged with each other,
The meshing region in which the teeth of the pair of gears mesh with each other is opposed to at least one end surface of the meshed teeth in a direction in which the tooth surfaces of each tooth are abutted with each other, and is generated at the time of overload. A gear device comprising: a regulating member that regulates a displacement of a meshed tooth in a rotation axis direction by abutting against at least one end face of the meshed tooth.   The regulating member is formed in a substantially U-shaped longitudinal section having a pair of pieces, and is arranged with both end faces of meshed teeth of the pair of gears sandwiched between the pair of pieces. The gear device according to claim 1.   The restricting member is formed in a disk shape having a diameter larger than the diameter of the tooth tip circle of one of the pair of gears, and the one gear on one end face of the meshed tooth of the other gear. The gear device according to claim 1, wherein the gear device is provided on a web surface of the one gear so as to face a portion projecting outward from the tooth tip of the gear.   The meshing of the teeth of the pair of gears with the opposing gears is carried out by pressing the tooth surfaces of at least one gear with the tooth surfaces of the other gear in the direction of the rotation axis using an elastic member. The gear device according to any one of claims 1 to 3, wherein the gear device is abutted against each other.

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