JP4353955B2 - Constant speed connection structure of motor and reduction gear - Google Patents

Description

The present invention relates to a constant speed coupling structure of a motor and a reduction gear.

  Conventionally, a hypoid reduction gear GM1 shown in FIGS. 7 and 8 is known (see Patent Document 1). FIG. 7 is a partial cross-sectional view of the hypoid reduction device GM1, and FIG. 8 is a cross-sectional view showing only the joint shaft 24 and the motor shaft 20 in the cross section taken along the line VIII-VIII in FIG.

  The hypoid reduction device GM1 has a configuration in which a motor 2 and a hypoid reduction device 3 are connected. Helical external teeth 22 are formed at the tip of the motor shaft 20 of the motor 2.

  The hypoid reducer 3 includes a joint shaft 24, a hypoid pinion 24P formed on the joint shaft 24, and a hypoid gear 25 with which the hypoid pinion 24P meshes. Power is transmitted to the output shaft 50 via the speed reduction mechanisms 28 and 29.

  In the casing 32, double cylindrical portions 32 </ b> A and 32 </ b> B extend in the direction of the motor shaft 20, and the outer cylindrical portion 32 </ b> A is connected to the casing of the motor 2. On the other hand, two bearings 34 and 35 are provided further inside the inner cylindrical portion 32B. The joint shaft 24 is rotatably supported with respect to the casing 32 by the two bearings 34 and 35.

  A hypoid pinion 24P is formed on the first and second speed reduction mechanisms 28 and 29 side of the joint shaft 24. A recess 24H into which the tip of the motor shaft 20, that is, a helical outer tooth 22, can be inserted is formed on the motor shaft 2 side of the joint shaft 24. Further, a slit S is formed along the axial direction so as to penetrate from the inside to the outside of the recess 24H (see FIG. 8), and clamped so as to cover the joint shaft 24 of the portion where the slit S is formed. A ring 50 is installed. That is, the power of the motor shaft 20 is connected by friction fastening between the tip of the motor shaft 20 inserted into the recess 24H (the portion where the helical outer teeth 22 are formed) by the clamp ring 50 and the slit. Can be transmitted to the hypoid gear 25.

JP 2005-201428 A

  In the hypoid speed reducer GM1 described above, “friction fastening using the clamp ring 50” is adopted, so that even if the diameter of the motor shaft 20 inserted into the recess 24H is slightly different, power can be transmitted due to the presence of the slit. Can be linked to a degree.

  However, on the other hand, the management of the fastening portion by the clamp ring 50, for example, the degreasing work required for fastening is complicated. Further, an installation space for installing the clamp ring 50 is indispensable, and there is a problem that the necessary space is enlarged particularly in the axial direction of the motor shaft. Furthermore, because of the frictional engagement, slipping may occur during use, and a large torque cannot be transmitted.

  On the other hand, the external teeth 22 ′ formed by cutting directly at the tip of the motor shaft 20 ′ and the internal teeth 24 G ′ in which the external teeth 22 ′ can be inserted and meshed without using the frictional fastening using the clamp ring 50. It is also conceivable to apply a configuration (see FIG. 9) for transmitting power using the meshing structure (hereinafter simply referred to as “gear meshing constant speed coupling structure”) to the hypoid reduction gear GM1. When such gears are engaged with each other, complicated labor such as torque management such as friction engagement described above is not necessary.

  In the case of such a gear meshing constant speed coupling structure, these teeth 22 'and 24G' are formed with a limit of precision that can be meshed from the viewpoint of preventing the occurrence of backlash at the coupling part and ensuring durability. Is done. However, no matter how accurate the manufacturing is, the possibility of manufacturing errors due to some cause in the manufacturing process and the accident during storage after manufacturing cannot be denied. For example, the shape of one tooth of an external tooth may be formed slightly larger than the other, or a dent may be formed on a part of the tooth due to an external impact after being formed normally. When a shape difference or deformation occurs in one of the plurality of teeth in this manner, depending on the shape difference or degree of deformation, the internal tooth side cannot be meshed well and rework is possible. When it becomes necessary or cannot be dealt with even by reworking, it is forced to change to another member. Of course, similar problems may occur not only in the external teeth but also in the internal teeth.

The present invention has been made to solve these problems, and while pursuing compactness by eliminating the need for a clamp ring, the present invention further prevents insertion into a part of a plurality of teeth. Even if (for example, a dent) occurs, it can be easily assembled without requiring reworking . As a result, the helical motor teeth and the inner teeth are connected to the motor shaft of the motor and the input shaft of the speed reducer. It is an object of the present invention to provide a constant speed coupling structure that can be directly gear-coupled with a motor .

The present invention relates to a motor that connects a motor in which helical external teeth are directly formed on a motor shaft and a speed reducer in which helical internal teeth that mesh with the helical external teeth are directly formed on an input shaft. And the constant speed connection structure of the reduction gear, wherein the above-mentioned problems are solved by configuring the external teeth and the internal teeth to have different numbers of teeth.

That is, at least one of the helical outer teeth and the helical inner teeth meshing with each other should be configured to be intermeshing with the missing tooth portion. It is possible to realize a structure in which the mating tooth surface is not meshed. In other words, even if a non-insertable factor (for example, a dent) occurs in any one of the teeth on the other side and the tooth cannot be meshed as it is, the tooth having the dent is replaced with the missing tooth portion. By being engaged with each other, it is possible to easily engage and connect without requiring rework of the portion where the dent is generated or further replacement with another same member.

  It should be noted that there are various patterns for determining which tooth is missing. For example, if one tooth is missing every other tooth, a one-to-two meshing relationship, that is, the number of teeth of one tooth is the other. The common multiple of the number of teeth may be used.

  In the present specification and claims, the term “missing teeth” means teeth that do not always mesh with the mating tooth surface during power transmission, and that specific teeth are not completely present ( As a matter of course, it is a concept that includes, for example, a case in which only a tooth of a specific tooth is formed to be smaller than a tooth of another tooth. Further, it is a concept including a case where only a specific tooth thickness (thickness in the pitch circle direction) is made small (thin).

By applying the present invention, a compact ring can be pursued by eliminating the need for a clamp ring when directly connecting a motor having a helical pinion motor shaft and a reduction gear . Also, troublesome torque management is unnecessary. Further, even when a cause of non-insertion (for example, a dent) occurs in any of the teeth, it is possible to easily connect without requiring reworking or the like.

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

  FIG. 1 is a cross-sectional view of a reduction gear GM101 that is an example of an embodiment to which the present invention is applied.

The reduction gear GM101 has a configuration in which a motor 102 and a reduction gear 103 are connected. A helical external tooth (helical pinion) 122 is directly cut and formed at the tip of the motor shaft 120.

Reducer 103 in the casing 132, the passage axis 1 24, and outputs a deceleration unit 104 for decelerating the power receiving power from該継axis 124, the power after the deceleration to mating machine (not shown) And an output shaft 150. The casing 132 has a double cylindrical portion extending toward the motor 102, and includes an outer cylindrical portion 132A on the outer side and an inner cylindrical portion 132B on the inner side. The joint shaft 124 is rotatably supported via bearings 134 and 135 further inside the inner cylindrical portion 132B. The two bearings 134 and 135 are arranged slightly apart in the axial direction of the motor shaft 120, and the projection 124 </ b> T of the joint shaft 124 is engaged with a portion therebetween, so that the axial direction of the joint shaft 124 is increased. The position is determined. Further, the position of the speed reducing portion 104 of the bearing 135 is abutted against the inner cylindrical portion 132 </ b> B, and the position of the motor 102 side of the bearing 134 is regulated by a retaining ring 137.

  A concave portion 124H is formed in a part of the joint shaft 124, and an internal tooth 124G corresponding to (engageable with) a helical outer tooth 122 formed at the tip of the motor shaft 120 is formed in the concave portion 124H. (The details of the connecting portion between the inner teeth 124G and the outer teeth 122 formed in the recess 124H will be described later). The joint shaft 124 has a first pinion extending from the center line of the pitch circle of the inner teeth 124G to the speed reduction portion 104 side (when the joint shaft alone is viewed, the first pinion corresponds to an output gear). 124P is formed. In the present embodiment, the first pinion 124P is a hypoid pinion. An oil seal 136 is disposed between the first pinion 124P and the recess 124H.

  The first pinion 124P meshes with a first gear (hypoid gear) 125. The first gear 125 is rotatably supported by the first gear support shaft 130. In FIG. 1, the first gear 125 and the second pinion 127 seem to mesh with each other, but the first gear support shaft 130 includes a second gear 126 having substantially the same diameter as the first gear. The second gear 126 meshes with the second pinion 127 that is rotatably supported by the second gear support shaft 140. The second gear support shaft 140 supports the third pinion 128 to be rotatable. The third pinion 128 meshes with the third gear 129. The third gear 129 is supported by the output shaft 150 and can rotate integrally with the output shaft 150.

Next, FIG. 2, the constant velocity coupling structure of the motor shaft 1 20 and relay shaft 1 24 will be described with reference to FIG. FIG. 2 is a cross-sectional view showing only the joint shaft 124 and the motor shaft 120 (helical external teeth 122 formed at the tip thereof) out of the cross section taken along the line II-II in FIG. FIG. 3 is a diagram illustrating a connection procedure in the case where a dent is generated on the motor shaft 120 as a non-insertable factor.

  In the present embodiment, every other internal tooth 124G formed in the recess 124H of the joint shaft 124 is omitted. That is, as shown in FIG. 2, the number of teeth of the external teeth 122 formed on the motor shaft 120 is 10, whereas the number of teeth of the internal teeth 124G is 5. As a result, the number of external teeth 122 is a common multiple of the number of internal teeth 124G. With such a configuration, even when a dent D is generated in one of the external teeth 122 as shown in FIG. 3A, the internal teeth are shown in FIG. By shifting the meshing position of 124G and the external teeth 122 by one tooth, it can be easily inserted without reworking the part where the dent D has occurred or replacing the entire motor shaft 120 with another object to mesh both gears, It becomes possible to connect. In FIG. 3 (A), it is depicted that the outer teeth 122 and the inner teeth 124G are inserted while wrinkles and dents D are generated, but the dents D generated on the outer teeth 122 are only shown. This does not indicate that insertion can be performed even if the dent D is present (the same applies hereinafter). Further, since the torque is transmitted by meshing between the gears without being engaged by friction, a clamp ring is unnecessary, and there is no need for degreasing work and friction management prior to connection. Further, there is no transmission loss due to slippage.

  Further, the constant velocity connection structure according to the present invention is not limited to the above-described embodiment, and may be configured as shown in FIG. 4, for example. For example, it is possible to configure the missing tooth portion N1 by using only one inner tooth 124G as a missing tooth among the outer teeth 122 and the inner teeth 124G meshing with each other. With such a configuration, even if the dent D is generated in any one of the plurality of external teeth 122 and cannot be connected to the internal teeth 124G as it is, the dent D is generated. The outer teeth 122 are connected in such a manner that they are positioned at the missing tooth portion N1 (in FIG. 4, the motor shaft 120 is rotated counterclockwise by three outer teeth so that the dent D is positioned at D ′. It is possible to easily insert and mesh the gears without reworking the part where the dent D is generated or replacing the entire motor shaft 120 with another object.

  On the other hand, as shown in FIG. 5, it is also possible to configure the missing tooth portion N2 with one of the external teeth 122 out of the meshing external teeth 122 and internal teeth 124G as a missing tooth. With this configuration, the dent D is generated in any of the plurality of inner teeth 124G, and the dent D is generated even when the dent D cannot be connected due to interference with the external teeth 122 as it is. The inner teeth 124G are connected in such a manner that they are positioned at the missing tooth portion N2 (in FIG. 5, the inner teeth 124G (joint shaft 124) are rotated counterclockwise by two outer teeth, and the impression D becomes D ' It is possible to easily insert and engage the gears without reworking the part where the dent D is generated or replacing the entire joint shaft 124 with another object. It becomes.

  Furthermore, it is also possible to adopt a configuration as shown in FIG. 6 by combining these. If comprised in this way, a dent will arise in any of the internal teeth 124G among the plurality of internal teeth 124G, and a dent will also occur in any of the external teeth 122 of the plurality of external teeth 122. Even in a case where they cannot be connected due to interference with each other, the external teeth 122 where the dent is generated are connected to the missing tooth portion N1, and the internal teeth 124G where the dent is generated are connected to the missing tooth portion N2. Thus, it becomes possible to easily insert and mesh the gears without reworking the part where the dent is generated or replacing the entire motor shaft 120 and joint shaft 124 with another object. Of course, in these configurations, not only a missing tooth portion for only one tooth, but also a missing tooth portion for two or more teeth may be formed continuously or intermittently.

In the above-described embodiment, examples of helical external teeth and internal teeth are shown. In the connecting structure using the F Rikarugia especially, its structure reprocessed like is difficult, the significance of adopting the constant velocity coupling structure according to the present invention is great.

  The present invention can be widely applied to various reduction devices other than the hypoid reduction device, for example, a reduction device using a bevel gear, a reduction device using a worm gear, a reduction device using a parallel gear, and a friction reduction device.

Sectional drawing of reduction gear device GM101 which is an example of embodiment to which this invention is applied. Sectional view of joint shaft and motor shaft along the arrow II-II line in FIG. The figure which shows the connection procedure when a dent etc. arise in a motor shaft FIG. 2 is a view showing an embodiment in which one of the internal teeth in the constant speed coupling structure of the reduction gear is missing, and is a view corresponding to FIG. It is a figure which shows the Example which made one missing tooth in the constant velocity connection structure of a reduction gear, and was equivalent, and is a figure equivalent to FIG. FIG. 2 is a view showing an embodiment in which one external tooth is missing in the constant speed coupling structure of the speed reducer, and further one internal tooth is missing, corresponding to FIG. Partial cross-sectional view of hypoid reduction gear GM1 described in Patent Document 1 Sectional drawing of the joint shaft and motor shaft along the arrow VIII-VIII line in FIG. Sectional view of the connecting portion showing the gear mesh constant velocity connecting structure

Explanation of symbols

GM101 ... Reduction gear 102 ... Motor 103 ... Reduction gear 120 ... Motor shaft 122 ... External teeth 124 ... Joint shaft 124H ... Concavity 124T ... Convex portion 124P ... First pinion 124G ... Internal teeth 125 ... First gear 126 ... Second gear 127 2nd pinion 128 ... 3rd pinion 129 ... 3rd gear 130 ... 1st gear support shaft 132 ... Casing 132A ... Outer cylindrical part 132B ... Inner cylindrical part 134, 135 ... Bearing 136 ... Oil seal 140 ... 2nd gear support shaft 150 ... Output shaft N1, N2 ... Missing tooth part

Claims (5)

A motor in which helical external teeth are directly formed on the motor shaft;
A reduction gear in which a helical inner tooth that meshes with the helical outer tooth is directly formed on the input shaft, and a motor and a constant speed connection structure of the reduction gear,
The number of teeth of the said external tooth and the said internal tooth differs. The constant velocity connection structure of the motor and reduction gear characterized by the above-mentioned. In claim 1,
The constant-speed coupling structure of the motor and the speed reducer, wherein the number of teeth of either the outer teeth or the inner teeth is a common multiple of the number of the other teeth. In claim 1 or 2,
A constant speed coupling structure of a motor and a reduction gear, wherein the number of teeth of the internal teeth is small. In claim 1,
A constant velocity coupling structure of a motor and a reduction gear, wherein at least one of the outer teeth or the inner teeth is a missing tooth. In claim 1,
A constant velocity coupling structure of a motor and a reduction gear, wherein at least one tooth of each of the outer teeth and the inner teeth is missing.

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