JP2005106076A - Parallel axes reduction gear and geared motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a concentric two-stage external engagement type parallel axes reduction gear of simple and low-cost structure. <P>SOLUTION: Near a central part of a casing 30, an intermediate plate 34 separate from a main body 32 of the casing 30 can be fitted to the main body 32 of the casing 30, and one end of an output shaft 16 is supported by the intermediate plate 34. An intermediate shaft 18 is arranged in parallel with an input shaft (motor shaft) 14 and the output shaft 16. A two-stage external engagement type parallel axes gear reduction mechanism is formed between the input shaft 14 and the intermediate shaft 18 and between the intermediate shaft 18 and the output shaft 16, and the shaft center O2 of the output shaft 16 and the shaft center O1 of the input shaft 14 are formed concentric with each other. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention relates to a circumscribing parallel shaft gear reducer and a geared motor in which the reducer and a motor are integrated.
About.

  The parallel shaft gear speed reduction mechanism decelerates the rotation of the shaft in which the pinion is incorporated through the pinion and gear respectively incorporated in the shafts arranged in parallel and takes out from the shaft in which the gear is incorporated. Since it is simple and low-cost, it has been widely used as one of the typical reduction mechanisms.

  The pinions and gears that make up the parallel shaft gear reduction mechanism include spur gears whose teeth are straight lines parallel to the shaft center, and helical gears whose teeth are formed obliquely with respect to the shaft center. A so-called involute tooth profile is used.

  In principle, the parallel shaft gear reduction mechanism can increase the gear ratio (number of teeth) on the driven side to increase the reduction ratio as much as possible, but it is practical to increase the gear diameter without limitation. Therefore, when the normal reduction ratio is larger than 3 to 4, a reduction mechanism having a similar structure is used in two or three stages.

  Patent Document 1 (Japanese Patent Application Laid-Open No. 59-2542) discloses an example of a two-stage externally meshing parallel gear speed reducer that uses this type of externally meshed parallel shaft gear speed reduction mechanism in two stages. Yes. The speed reducer disclosed in this publication has “non-concentric” input and output shafts. That is, the axis of the input shaft and the axis of the output shaft do not match (deviation).

JP 59-2542 A

  However, in the field where a reduction gear is applied, a situation in which concentricity between the input shaft and the output shaft is often required. In consideration of the condition that “the input shaft and the output shaft are concentric”, the externally meshed parallel shaft gear reduction mechanism is not necessarily a suitable reduction mechanism.

  More specifically, the externally meshing parallel shaft gear reduction mechanism performs deceleration between two shafts, so that in the case of a single stage type, the input side shaft and the output side shaft are inevitably required. The axis is misaligned. In the case of the two-stage type, it is possible on the desk skeleton to be concentric by returning the axis shifted in the first stage to the original in the second stage, but as a practical matter, at least the output shaft is It is often difficult to support both ends.

  In other words, if the input shaft is concentrically present on one end side of the output shaft, the both-end support cannot be performed. Nevertheless, in order to realize both-end support of the output shaft, the output side casing is lengthened in the axial direction to gain a span for both-end support, or a casing with a very special structure is formed. It is necessary to take measures such as increasing the cost, increasing the size, increasing the weight, and increasing the weight. Therefore, as in the example of this publication, in the case of a two-stage circumscribed meshing parallel shaft gear reduction mechanism, the actual situation is that the axis of the input shaft and the output shaft are mostly non-concentric. It is.

  The present invention has been made in view of such a conventional situation, and utilizes a circumscribed meshing parallel shaft gear reducer that can be a concentric and two-stage type with a simple and low-cost structure, and the reducer. The object is to provide a geared motor.

  The present invention relates to a parallel shaft gear reducer in which an input shaft and an output shaft parallel to the input shaft are housed in a casing, and an intermediate plate separate from the casing main body is provided near the central portion of the casing. The output shaft is supported by the intermediate plate, the intermediate shaft is disposed in parallel with the input shaft and the output shaft, and the intermediate shaft is interposed between the input shaft and the intermediate shaft. By forming a two-stage externally meshing parallel shaft gear reduction mechanism between the shaft and the output shaft, and by concentrating the shaft center of the output shaft and the shaft center of the input shaft, It solves the above problems.

  In the circumscribing parallel shaft gear reducer according to the present invention, the input shaft and the output shaft are basically concentric while using the parallel shaft gear reduction mechanism. The term “concentric” as used in this specification does not necessarily refer to the case where the axes are completely coincident with each other, but the axes are substantially regarded as being concentric (contained within a predetermined range). Includes cases where they match. For example, if the difference in the distance between each shaft center and the skirt surface or bolt position where the casing is installed is within 3%, it can be said that it falls within the “predetermined range” here, and is substantially concentric. Enter the category.

  In the present invention, in order to realize the concentricity of the input / output shaft, an intermediate plate separate from the casing is attached and arranged near the axial end of the output shaft. The end of the output shaft is supported by this intermediate plate. Accordingly, the output shaft can be supported at both ends by the casing and the intermediate plate without enlarging the casing in the axial direction more than necessary.

  Further, since the intermediate plate is separate from the casing main body, it is possible to avoid complication of the structure of the casing main body itself and to ensure ease of assembly.

  On the other hand, an intermediate shaft is arranged in parallel with the input / output shaft, and a two-stage circumscribing parallel shaft gear mechanism is formed between the input shaft and the intermediate shaft, and between the intermediate shaft and the output shaft. Thereby, each element can be assembled firmly and easily, and concentricity between the input shaft and the output shaft can be ensured.

  The present invention does not necessarily require that the intermediate plate supports the input shaft and the intermediate shaft, but as described later, if the input shaft and the intermediate shaft are also supported by the intermediate plate, A reduction gear with higher rigidity can be obtained.

  It is possible to obtain a concentric / two-stage circumscribed meshing parallel shaft gear reducer with a simple and low-cost structure.

  Hereinafter, examples of embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows an example of a geared motor GM1 to which the embodiment of the present invention is applied.

  This geared motor GM1 is obtained by integrating a motor M1 and a circumscribing parallel shaft gear reducer G1.

  The motor M1 includes a motor shaft 14 rotatably supported by a pair of bearings (only the bearing 12 on the parallel shaft gear reducer G1 side is shown). The tip of the motor shaft 14 faces the inside of the parallel shaft gear reducer G1, and also serves as the input shaft of the parallel shaft gear reducer G1. For this reason, for convenience, the motor shaft 14 in this embodiment is appropriately referred to as an input shaft 14.

  The parallel shaft gear reducer G1 includes the input shaft 14 and an output shaft 16 disposed in parallel with the input shaft 14, and further includes an intermediate shaft 18 disposed in parallel with the input shaft 14 and the output shaft 16.

  The input shaft 14 and the output shaft 16 are concentric. Note that the term “concentric” here does not require that the axial centers coincide completely in design, but includes a case where they are substantially concentric. “Substantially concentric” means, for example, a distance L1 from the contact surface P to the mounting body to the axial centers O1 and O2 of the input shaft 14 and the output shaft 16 in the case of leg mounting as in this embodiment. , L2 difference ΔL (= L1−L2) may be considered to be in the category of “substantially concentric” when it is within the range of 3% of the distance L1. In the illustrated example, the size of ΔL is slightly exaggerated for easy understanding.

  The input shaft 14 has a first-stage pinion 20 integrated with a key 22. The intermediate shaft 18 incorporates a first-stage gear 24 and a second-stage pinion 26 that mesh with the first-stage pinion 20. The second stage pinion 26 meshes with a second stage gear (output gear) 28 incorporated in the output shaft 16.

  On the other hand, the casing 30 of the parallel shaft gear reducer G <b> 1 includes a main body 32, an intermediate plate 34, a cover 36, an adapter 38, and legs 40.

  The main body 32 of the casing 30 has a shape set larger than the side (lower side in the figure) where the intermediate shaft 18 exists (upper side in the figure) with respect to the axis O2 of the output shaft 16. . The main body 32 includes a stepped portion 32A in the vicinity of the center with respect to the axial direction. An intermediate plate 34 is incorporated in the stepped portion 32A. The intermediate plate 34 is formed separately from the main body 32, and can be attached / detached via a bolt 42. The intermediate plate 34 supports one end of the output shaft 16 via a bearing 44. As a result, the output shaft 16 is supported in a supported state together with the bearing 45 on the main body 32 side.

  The intermediate plate 34 supports the input shaft 14 via a bearing 41 and supports the intermediate shaft 18 via a bearing 46. That is, the input shaft 14 is supported at three points together with the bearing on the motor M side (only the bearing 12 is shown), and the intermediate shaft 18 is supported at two points together with the bearing 47 on the main body 32 side.

  The cover 36 of the casing 30 also serves as a cover on the speed reducer side of the motor M1 and has a substantially circular outer periphery that is concentric with the motor shaft 14. The cover 36 incorporates the bearing 12 described above, and a part of the motor shaft (input shaft) 14 is supported.

  An adapter 38 is interposed between the main body 32 of the casing 30 and the cover 36. The adapter 38 is for absorbing (filling in) a difference in dimensions between the cross-sectional shape of the main body 32 of the casing 30 and the outer shape of the cover 36. The cover 36 and the main body 32 are connected by a bolt 39 with an adapter 38 interposed.

  Since the mating surface 38A is circular, the seal between the adapter 38 and the cover 36 can be almost completely performed by packing the contact portion and tightening the bolt 39. However, the sealing between the adapter 38 and the main body 32 has a tightening force increased by the bolt 37 and the sealing performance is improved because the mating surface 38B is not circular.

  The leg portion 40 of the casing 30 is for installing the casing 30 together with the motor M1 on an installation body (not shown), and reference numeral 40A in the figure is a bolt hole.

  Next, the operation of the geared motor GM1 will be described.

  When the motor shaft 14 of the motor M1 (that is, the input shaft of the parallel shaft gear reducer G1) 14 rotates, the first-stage pinion 20 attached to the tip of the motor M1 rotates. This rotation is transmitted to the intermediate shaft 18 via the first-stage gear 24, and the first-stage deceleration is realized. When the intermediate shaft 18 rotates, the second-stage pinion 26 incorporated in the intermediate shaft 18 rotates at the same speed, the output shaft 16 rotates through the second-stage gear 28, and a total of two-stage deceleration is achieved. Realized.

  Here, the portion of the first stage pinion 20 of the input shaft 14 is supported at two points of the bearings 12 and 41 (three points when paying attention to the entire motor shaft). Compared to the structure supporting the first-stage pinion 20, the support rigidity can be improved, and low vibration and low noise can be realized. Since the input shaft 14 rotates at a high speed, the effect of reducing vibration and noise due to this rigidity enhancement is great. Further, since the output shaft 16 and the second-stage pinion 26 are both supported by the presence of the intermediate plate 34, it is possible to maintain high support rigidity in this portion.

  The intermediate plate 34 is formed as a separate part (separate body) from the main body 32 of the casing 30 and is configured to be connected to the main body 32 side via a bolt 42. There is no need for complication, and an increase in molding cost can be suppressed. Further, since the assembly / disassembly of the second stage side can be performed from the motor M1 side (input shaft 14 side), the assembling property and the maintenance property can be improved.

  Furthermore, since the adapter 38 is interposed between the main body 32 of the casing 30 and the cover 36, the difference in dimensions between the cross-sectional shape of the main body 32 of the casing 30 and the outer shape of the cover 36 can be absorbed well. . For example, in the geared motor GM <b> 2 according to this embodiment, half of the first stage gear 24 is positioned radially outward from the intermediate shaft 18. Therefore, due to the presence of the gear 24, the casing 30 enters and the dimension of one side (the lower side in the example of FIG. 1) is considerably larger than the dimension of the other side (the same upper side) with respect to the shaft centers of the output shafts 14 and 16. turn into. On the other hand, the cover 36 of the motor M has a circular shape that is substantially concentric with the input and output shafts 14 and 16. Therefore, the process of misalignment of the axial center between the cover 36 and the cross-sectional shape of the main body 32 becomes a problem.

  Here, when trying to keep the inner volume of the casing 30 as small as possible, for example, the reference radius of the entire casing 30 is designed so that all the gears except the gear 24 can be accommodated. A method of projecting only the portion to be extended to the outer peripheral side is conceivable.

  However, this method complicates the shape of the casing 30 and greatly increases the molding cost of the casing 30. Further, even if the shape is such that the overhang is eliminated, an inward rising portion for absorbing (filling in) the difference between the cross-sectional shape of the main body 32 and the shape of the cover 36 is formed on the main body 32 side. It is necessary to increase the molding cost of the casing 30 as well.

  On the other hand, in this embodiment, a circular mating surface 38A is formed on the cover 36 side of the adapter 38. On the other hand, the mating surface on the main body 32 side of the adapter 38 has a shape bulging outward in the radial direction by the amount of the gear 24. Therefore, there is no need to form a rising portion on the main body 32 side to fill in the difference in shape. Therefore, coupled with the fact that the intermediate plate 34 is a separate part, the shape of the main body 32 of the casing 30 can be relatively simplified, and although it can be simplified, the cost can be reduced and the size can be reduced.

  In addition, by attaching the motor M via the adapter 38, there is an advantage that the motor cover can also be used as the cover of the reduction gear G2, even if it is not a dedicated motor.

  Next, an example of another embodiment of the present invention will be described with reference to FIG.

  In this geared motor GM2, the casing 130 of the parallel shaft gear reducer G2 is installed by a bolt (not shown) through the through hole 140A of the flange portion 140, not by the leg portion. The through holes 140 </ b> A are equally arranged on a concentric circle with respect to the axis 02. The output shaft 116 is directly inserted into a hollow portion of a rotating body (not shown) of the counterpart machine, or is connected to the counterpart machine side via a coupling. The tip of the input shaft 114 is supported by a dedicated bearing 141.

  In the present embodiment, the motor shaft center 01 and the shaft center 02 of the parallel shaft gear reducer are substantially concentric, and furthermore, the through holes 140A of the flange portion 140 are equally arranged with respect to the shaft center 02. The balance when attached to the head is good and vibration can be reduced.

  Since the other configuration is basically the same as that of the previous embodiment, the same or similar parts in the figure are given the same reference numerals in FIG.

  FIG. 3 shows an example of an embodiment of a parallel shaft gear reducer G3 that is independent of the motor.

  In this embodiment, the input shaft 214 is incorporated as one independent component of the parallel shaft gear reducer G3. The input shaft 214 protrudes from one side of the casing 230 of the parallel shaft gear reducer G3 while being supported by two pairs of bearings 212 and 241. The output shaft 216 protrudes from the other side of the casing 230 in a state of being supported by a pair of bearings 244 and 245 as in the above-described embodiment. As a result, a so-called double shaft type speed reducer is formed. The parallel shaft gear reducer G3 is connected to the motor side or the counterpart machine side via a coupling (not shown). Other configurations are basically the same as those of the embodiment shown in FIG. 1, and therefore, the same or similar parts are denoted by reference numerals obtained by adding 200 to the reference numerals assigned in the embodiment of FIG. Stop and redundant explanations are omitted.

  In the present embodiment, by providing the adapter 238, it is possible to use a cover used in another speed reducer (different from the parallel shaft gear speed reducer G3).

  In each of the above embodiments, the end of the input shaft is supported by the intermediate plate. However, in the present invention, the input shaft does not necessarily have to be supported by the intermediate plate. That is, for example, in the case where the motor shaft also serves as the input shaft of the parallel shaft gear reducer as shown in FIG. 1 or FIG. 2, the motor shaft (input shaft) is cantilevered in the casing. It is good also as a structure which makes it face to.

  Further, in the above-described embodiments, the configuration in which a part of the intermediate shaft is supported by the intermediate plate is employed, but this configuration is not an essential configuration. For example, a large through hole for the intermediate shaft may be formed in the intermediate plate, and the intermediate shaft itself may be supported at both ends by the casing body and the cover through the through hole of the intermediate plate. Good.

  Furthermore, in each of the above embodiments, an adapter is interposed between the cover of the casing and the main body so as to absorb (fill in) the difference in shape between the cover and the main body. The adapter is not always a necessary member. For example, when the outer shape of the cover is matched with the opening shape on the cover side of the main body, the main body and the cover can be directly connected without interposing the adapter.

  The present invention can realize a reduction gear or a geared motor that requires coaxiality in the input shaft and the output shaft with a simple and low-cost configuration. Or it can apply to a drive system.

The longitudinal cross-sectional view which shows the example of embodiment of the geared motor to which this invention was applied Vertical sectional view showing an example of another embodiment The longitudinal cross-sectional view which shows the example of embodiment of the parallel shaft gear reducer to which this invention was applied

Explanation of symbols

GM1, GM2, GM3 ... Geared motor G1, G2, G3 ... Parallel shaft gear reducer M1, M2, M3 ... Motor 14,114,214 ... Motor shaft (input shaft)
16, 116, 216 ... Output shaft 18, 118, 218 ... Intermediate shaft 20, 120, 220 ... First stage pinion 24, 124, 224 ... First stage gear 26, 126, 226 ... Second stage pinion 28, 128, 228 ... 2nd stage gear 30, 130, 230 ... Casing 32, 132, 232 ... Main body 34, 134, 234 ... Intermediate plate 36, 136, 236 ... Cover

Claims (6)

In a parallel shaft gear reducer in which an input shaft and an output shaft parallel to the input shaft are housed in a casing,
Near the center of the casing, an intermediate plate separate from the casing main body can be attached to the casing main body, and the intermediate plate supports one end of the output shaft,
An intermediate shaft is arranged in parallel with the input shaft and the output shaft,
Between the input shaft and the intermediate shaft, between the intermediate shaft and the output shaft, a two-stage externally meshing parallel shaft gear reduction mechanism is formed, and the shaft center of the output shaft and the input A parallel shaft gear reducer characterized in that the shaft center is concentric. In claim 1,
At least one of the input shaft and the intermediate shaft is supported by the intermediate plate. In claim 1 or 2,
The input shaft protrudes from one side of the casing;
The parallel shaft gear reducer characterized in that the output shaft projects from the other side of the casing. In any one of Claims 1-3,
An adapter is interposed between the main body of the casing and a cover that supports the input shaft. In a geared motor in which a parallel shaft gear reduction mechanism having a parallel shaft gear reduction mechanism in a casing and a motor are integrated,
Near the center of the casing, an intermediate plate separate from the casing main body can be attached to the casing main body, and the intermediate plate supports one end of the output shaft.
The motor shaft of the motor faces the casing of the speed reducer as an input shaft of the parallel shaft gear speed reducer,
An intermediate shaft is arranged in parallel with the motor shaft and the output shaft of the parallel shaft gear reducer,
Between the motor shaft and the intermediate shaft, between the intermediate shaft and the output shaft, a two-stage externally meshing parallel shaft gear reduction mechanism is formed, and the shaft of the output shaft and the motor shaft A geared motor characterized in that it is concentric with the shaft axis. In claim 5,
A geared motor, wherein at least one of the motor shaft and the intermediate shaft is supported by the intermediate plate.

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