JP2018021566A - Power extraction device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power extraction device which can utilize a dead space around a spline while extracting rotational power suitable for accessories.SOLUTION: A power extraction device 10 includes: a rotary shaft 12 disposed at the radial outer side of an output shaft 21; an extraction gear 13 fixed to the rotary shaft 12; and a driven gear 14 which is fixed to a driving shaft 30 and directly or indirectly meshed with the extraction gear 13. Teeth 15 disposed at an outer periphery of the extraction gear 13 are meshed with a male spline 22 formed at an outer periphery of the output shaft 21.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a power take-out device.

  There has been proposed a power take-out device that transmits power shifted by a transmission to an in-vehicle body component via a gear fixed to the output shaft of the transmission and rotating integrally with the output shaft (for example, Patent Document 1). 2). These power take-out devices have a structure that takes out relatively large rotational power in special-purpose automobiles such as construction vehicles, agricultural vehicles, and industrial vehicles. Therefore, it becomes over-spec for on-vehicle bodywork such as a pump mounted on a normal car or a large car, and in addition to the high manufacturing cost, increasing the size and length is a problem.

JP 2012-233544 A Japanese Utility Model Publication No. 58-124330

  By the way, in a vehicle, an output shaft of a transmission that shifts and outputs rotational power output from a driving source such as an engine and a propeller shaft are connected via a shaft coupling. Specifically, the male spline formed at the output end portion of the output shaft and the female spline formed at the input end portion of the shaft coupling are connected by spline coupling.

  For example, when the male spline is machined by a hobbing machine such as a hob cutter, an extra portion is generated in the axial direction of the output shaft by the amount of the hob cutter diameter, and this portion becomes a dead space.

  The present invention has been made in view of the above, and an object of the present invention is to provide a power take-out device that can utilize a dead space around a spline while taking out rotational power suitable for a bodywork. It is in.

  The power take-out device of the present invention that achieves the above-mentioned object is a power take-out device that transmits a part of the rotational power from the power transmission shaft to the drive shaft of the bodywork, the rotational power generated by the drive source, A rotating shaft disposed radially outside the power transmission shaft; an extraction gear fixed to the rotating shaft; and a driven gear fixed to the drive shaft and meshed directly or indirectly with the extracting gear. And the teeth disposed on the outer periphery of the take-out gear mesh with a male spline formed on the outer periphery of the power transmission shaft.

  Examples of the bodywork here include an oil pump that circulates lubricating oil, a small generator, and the like as an on-vehicle bodywork of a normal automobile or a large automobile.

According to the present invention, the tooth of the take-out gear meshes with the male spline formed on the outer periphery of the power transmission shaft, and a part of the rotational power output from the drive source directly from the male spline by the take-out gear is obtained. It is configured to take out.

  That is, by using the take-out gear that directly meshes with the male spline, the take-out gear can be made lighter and thinner than the gear fixed to the conventional power transmission shaft, so that the extracted rotational power can be reduced accordingly. As a result, it is advantageous to eliminate over-spec for the bodywork driven with a small rotational power, and it is possible to avoid an increase in the size and length of the apparatus and to reduce the manufacturing cost. In addition, since the take-out gear is lighter, thinner, and shorter, the take-out gear can be engaged with the excess portion of the male spline that is generated when the male spline is processed on the power transmission shaft, and the dead space around the spline can be effectively utilized.

1 is a perspective view illustrating a first embodiment of a power take-out device of the present invention. FIG. 2 is a longitudinal sectional view in the axial direction illustrating the power take-out device in FIG. 1. It is a schematic diagram which illustrates meshing | engagement of the spline of FIG. 1, an extraction gear, and a driven gear. It is a longitudinal cross-sectional view of the axial direction which illustrates 2nd embodiment of the power take-out apparatus of this invention. It is a longitudinal cross-sectional view of the axial direction which illustrates 3rd embodiment of the power take-out apparatus of this invention.

  Embodiments of the present invention will be described below with reference to the drawings. In the figure, x is the axial direction of the output shaft 21, and y is the radial direction of the output shaft 21 in a direction orthogonal to the axial direction. In FIG. 1, the gear case 11 and the transmission case 23 of the transmission 20 are shown by dotted lines in order to explain the internal structure of the power take-off device 10, and only the gear case 11 is shown by dotted lines in FIGS. 2 and 4. Yes.

  As illustrated in FIG. 1 and FIG. 2, the power take-out device 10 of the first embodiment takes a part of the rotational power from the output shaft (output shaft) 21 of the transmission 20 and supplies it to the drive shaft 30 of the in-vehicle bodywork product. To communicate. The output shaft 21 is a power transmission shaft that transmits rotational power generated in an engine as a drive source (not shown). The drive shaft 30 is a shaft that drives the on-vehicle bodywork with the transmitted rotational power.

  Examples of the on-vehicle bodywork device include a device that can be driven by a part of the rotational power generated by the engine, and an oil pump that circulates lubricating oil and a small generator.

  The transmission 20 includes a transmission gear (not shown), an output shaft 21, and a transmission case 23. The transmission 20 shifts the rotational power transmitted from the engine to a propeller shaft that transmits the rotational power from the output shaft 21 to the drive wheels. Output.

  The output shaft 21 is connected to the propeller shaft via a shaft coupling 40. The output shaft 21 has a male spline 22 at its output end (end on the propeller shaft side). The male spline 22 is an involute spline. For example, a plurality of grooves in which the output end portion of the output shaft 21 is recessed from the outside in the radial direction y to the inside by a gear cutting machine such as a hob cutter is provided in the circumferential direction of the output end portion. Are formed at equal intervals.

  The transmission case 23 rotatably supports the output shaft 21 and the shaft coupling 40 through the bearing 24 at one end and the bearing 25 at the other end, and covers the surplus portion 22 b of the male spline 22.

  The shaft coupling 40 is a flange-type shaft coupling (conventional type), and connects the flange on the output shaft 21 side and the flange on the propeller shaft side with bolts to couple them together. The shaft coupling 40 has a cylindrical portion 41 as a power transmission cylinder at the input end (end on the output shaft 21 side) and a flange 42 at the output end (end on the propeller shaft side).

  A female spline 43 is formed on the inner periphery of the cylindrical portion 41. The female spline 43 is spline-coupled with the male spline 22 by large diameter matching. For example, a plurality of grooves recessed from the inner side to the outer side in the radial direction y by broaching or electric discharge machining are equally spaced in the circumferential direction. It is formed by cutting.

  The output shaft 21 and the shaft joint 40 are fitted together by spline coupling, with the male spline 22 of the output shaft 21 inserted into the female spline 43 of the shaft joint 40. Further, the output end face of the output shaft 21 is fastened to the radial center portion of the flange 42 by a bolt 44.

  The shaft coupling 40 and the propeller shaft are fastened to a flange fixed to the propeller shaft side by a bolt 46 inserted through a fastening hole 45 penetrating with a space in the circumferential direction of the flange 42 of the shaft coupling 40.

  The male spline 22 includes a coupling portion 22a and a surplus portion 22b that are adjacent to each other in the axial direction x. As described above, the coupling portion 22 a is a portion that is inserted into the cylindrical portion 41 of the shaft coupling 40 and is spline-coupled with the female spline 43 formed on the inner periphery of the cylindrical portion 41. The surplus portion 22b is a portion excluding the connecting portion 22a, and is a portion that is not inserted into the cylindrical portion 41 and is not splined. The surplus portion 22b is generated due to machining clearance. For example, when the surplus portion 22b is machined by a hobbing machine such as a hob cutter, the surplus portion 22b extends in the axial direction x by the amount of the hob cutter diameter.

  The power take-out device 10 includes a gear case 11, a rotating shaft 12, a take-out gear 13, and a driven gear 14, and teeth 15 arranged on the outer periphery of the take-out gear 13 are formed on the outer periphery of the output shaft 21. The spline 22 is engaged with the spline 22.

  The gear case 11 is fixed to the mission case 23 and protrudes toward the outside of the mission case 23. The gear case 11 supports the rotary shaft 12 and the drive shaft 30 in a rotatable manner, and covers the take-out gear 13 and the driven gear 14. One end of the drive shaft 30 comes out of the gear case 11 and is connected to the on-vehicle bodywork.

  The rotary shaft 12 is disposed inside the gear case 11 and on the radially outer side of the output shaft 21 so that the axial direction thereof is parallel to the axial direction of the output shaft 21.

  The take-out gear 13 is fixed to the rotary shaft 12 and is constituted by a spur gear having an involute tooth shape. The tooth width B3 of the take-out gear 13 is narrower than the width B2 of the surplus portion 22b in the axial direction x.

  The driven gear 14 is fixed to the drive shaft 30 and is constituted by a spur gear having an involute tooth shape. The tooth width B4 of the driven gear 14 is narrower than the width B2 of the surplus portion 22b in the axial direction x, like the tooth width B3 of the take-out gear 13.

  As illustrated in FIG. 3, in order for the teeth 15 arranged on the outer circumference of the take-out gear 13 to mesh with the male spline 22 formed on the outer circumference of the output shaft 21, the take-out gear 13 is set as follows. ing.

  The tip circle diameter dk3 of the take-out gear 13 is smaller than the tip circle diameter dk2 of the male spline 22. The root diameter df3 of the take-out gear 13 is smaller than the root diameter df2 of the male spline 22. The pitch circle diameter (reference circle diameter) d3 of the take-out gear 13 is smaller than the pitch circle diameter d2 of the male spline 22. The number of teeth Z3 of the take-out gear 13 is smaller than the number of teeth Z2 of the male spline 22.

  The module (diametral pitch) m3 (pitch circle diameter d3 / number of teeth Z3) of the take-out gear 13 is equal to the module m2 (pitch circle diameter d2 / number of teeth Z2) of the male spline 22. That is, the normal line pitch tm3 of the take-out gear 13 is equal to the normal pitch tm2 of the male spline 22.

  Thus, by making the module m3 of the takeout gear 13 equal to the module m2 of the male spline 22, the teeth 15 of the takeout gear 13 can be engaged with the male spline 22.

  Next, the operation of the power take-out device 10 will be described. When rotational power is transmitted from the engine to the transmission 20, the rotational power is shifted by the transmission 20. Next, the shifted rotational power is transmitted to the output shaft 21 and is transmitted to the propeller shaft via the shaft coupling 40. At this time, a part of the rotational power transmitted to the propeller shaft is transmitted to the take-out gear 13 meshed with the male spline 22 formed at the output end of the output shaft 21. Next, the rotational power transmitted to the take-out gear 13 is transmitted to the drive shaft 30 via the driven gear 14. The on-vehicle bodywork is driven by the rotational power transmitted to the drive shaft 30.

  As described above, in the power take-out device 10 of this embodiment, the tooth 15 of the take-out gear 13 and the male spline 22 formed on the outer periphery of the output shaft 21 are engaged with each other, and the take-out gear 13 directly from the male spline 22. Part of the rotational power is taken out.

  In other words, by using the take-out gear 13 that directly meshes with the male spline 22, the take-out gear 13 is lighter and thinner than the gear fixed to the conventional power transmission shaft. The rotational power transmitted to the drive shaft 30 via the gear 14 can be reduced. Thereby, it becomes advantageous for the elimination of the overspec for the on-vehicle bodywork that is driven with a small rotational power, and it is possible to prevent the power take-out device 10 from becoming heavy and large and to reduce the manufacturing cost.

  Further, since the take-out gear 13 is lighter, thinner, and shorter, the take-out gear 13 can be engaged with the surplus portion 22b generated when the male spline 22 is processed on the output shaft 21, and the dead space around the spline can be effectively utilized. .

  Specifically, the lightening and thinning of the takeout gear 13 will be described. In this embodiment, the takeout gear 13 is made thinner by making the tooth width B3 of the takeout gear 13 smaller than the width B2 in the axial direction x of the surplus portion 22b. ing. Further, the take-out gear 13 is shortened by making the pitch circle diameter d3 of the take-out gear 13 smaller than the pitch circle diameter d2 of the male spline 22.

  In this way, by making the take-out gear 13 lighter, thinner, and smaller, it is possible to eliminate over-spec for the vehicle-mounted bodywork and to effectively use the dead space around the spline.

An on-vehicle bodywork such as an oil pump for circulating lubricating oil and a small generator can be driven by a part of the rotational power output from the engine. Therefore, as described above, by making the take-out gear 13 lighter, thinner, and smaller, the rotational power transmitted from the drive shaft 30 is optimal without being over-spec with respect to the on-vehicle bodywork.

  In the power take-out device 10 of this embodiment, the surplus portion 22b of the male spline 22 of the output shaft 21 is utilized. As a result, even when part of the rotational power is taken out from the output shaft 21, it is possible to avoid an increase in the thickness of the transmission 20 without extending the length of the output shaft 21 in the axial direction x.

  Since the rotational power taken out by the power take-out device 10 is reduced, the reduction in rotational power transmitted from the output shaft 21 to the propeller shaft is reduced. In addition to the increase in the thickness of the power take-off device 10, the increase in the thickness of the transmission 20 is also avoided, so that the weight of the vehicle can be reduced. Accordingly, the fuel efficiency of the vehicle can be improved.

  As illustrated in FIG. 4, in the power take-out device 10 of the second embodiment, the take-out gear 13 is interposed between the shaft coupling 40 and the rotation speed sensor 50 with respect to the first embodiment. Further, an intermediate gear 16 that meshes with the take-out gear 13 and the driven gear 14 is interposed, and the take-out gear 13 and the driven gear 14 are indirectly meshed with each other.

  The rotation speed sensor 50 is a sensor that detects the rotation speed of the output shaft 21. Examples of the rotational speed sensor 50 include a vehicle speed sensor that outputs a vehicle speed from the detected rotational speed.

  The rotational speed sensor 50 includes a driven gear 51 that is spline-coupled with the surplus portion 22 b of the male spline 22 and rotates integrally with the output shaft 21, and an electromagnetic pickup 52 that detects the rotation of the teeth of the driven gear 51. ing.

  The tooth width B3 in the axial direction x of the take-out gear 13 of this embodiment is determined from the width B2 of the surplus portion 22b, the width B5 in the axial direction x of the bearing 24 that is a ball spline, and the width B6 in the axial direction x of the driven gear 51. It is narrower than the value obtained by subtracting.

  By setting the tooth width B3 of the take-out gear 13 in this way and making it thin, the rotation speed sensor 50 can be attached to the surplus portion 22b, and the dead space around the spline can be used more effectively.

  The take-out gear 13 may be engaged with the surplus portion 22b of the male spline 22, and the take-out gear 13, the rotation speed sensor 50, and the shaft coupling 40 may be arranged in order from the input side to the output side of the output shaft 21. Good.

  The intermediate gear 16 is a spur gear similar to the take-out gear 13 and the driven gear 14. Thus, by interposing the intermediate gear 16 between the take-out gear 13 and the driven gear 14, the driven gear 14 can be separated from the output shaft 21 and the shaft coupling 40. That is, by adjusting the number of intermediate gears 16 interposed between the take-out gear 13 and the driven gear 14, the degree of freedom in layout increases.

  As illustrated in FIG. 5, the power take-out device 10 of the third embodiment includes a cogged belt (toothed belt) 17 instead of the rotating shaft 12 and the take-out gear 13 with respect to the embodiment described above. . The cogged belt 17 is an endless belt and is wound around the surplus portion 22 b of the male spline 22 and the driven gear 14.

The cogged belt 17 has teeth that mesh with the surplus portion 22b and the driven gear 14 on the contact surface. The teeth are preferably configured to approximate an involute tooth shape when meshed with the surplus portion 22b and the driven gear 14. That is, when the arc portion in contact with the surplus portion 22b and the driven gear 14 is regarded as a gear, the module of the gear may be equal to the module m2 of the male spline 22.

  The width B7 of the cogged belt 17 in the axial direction x is narrower than the width B2 of the surplus portion 22b in the axial direction x, like the tooth width B3 of the take-out gear 13 of the first and second embodiments, and the rotational speed sensor 50 is provided. In this case, the width is set narrower than the value obtained by subtracting the width B5 and the width B6 from the width B2.

  As in this embodiment, even if the cogged belt 17 is used instead of the take-out gear 13, a part of the rotational power can be taken out directly from the male spline 22, and the dead space around the spline can be effectively utilized. .

  In the above-described embodiment, a motor generator can be exemplified as the power source in addition to the engine, and the present invention can be applied to a hybrid vehicle using both the engine and the motor generator as drive sources.

  The power transmission shaft may be a shaft in which the male spline 22 is formed at one end or in the middle and the surplus portion 22b exists. However, like the output shaft 21, it is preferable that the male spline 22 and the female spline 43 are immovable with respect to each other in the axial direction x and the axis B of the surplus portion 22b in the axial direction x has a fixed value.

  The shaft coupling 40 may be a reverse slip type, or may be constituted by a universal joint in which a female spline is formed at one end.

  In the above-described embodiment, a pipe may be connected to the gear case 11 so that lubricating oil is supplied into the gear case 11.

  In the above-described embodiment, the example in which the power take-out device 10 is mounted on the vehicle and transmits the rotational power to the on-vehicle bodywork has been described. However, the present invention is not limited thereto, and the rotational power output from the drive source is described. As long as a part of the shaft is taken out from the power transmission shaft and transmitted to the drive shaft of the bodywork, it is sufficient.

DESCRIPTION OF SYMBOLS 10 Power take-out apparatus 12 Rotating shaft 13 Take-out gear 14 Driven gear 15 Tooth 21 Output shaft 22 Male spline 30 Drive shaft

Claims (6)

A power take-out device that takes out a part of the rotational power generated in the drive source from the power transmission shaft and transmits it to the drive shaft of the bodywork,
A rotating shaft disposed radially outside the power transmission shaft; an extraction gear fixed to the rotating shaft; and a driven gear fixed to the drive shaft and meshed directly or indirectly with the extracting gear. Prepared,
A power take-out device in which teeth arranged on the outer periphery of the take-out gear are in mesh with a male spline formed on the outer circumference of the power transmission shaft. In a state where the power transmission shaft is inserted into a power transmission cylinder in which a female spline is formed on the inner periphery, a coupling portion that is spline coupled to the male spline and a surplus portion excluding the coupling portion are formed,
The power take-out device according to claim 1, wherein teeth arranged on an outer periphery of the take-out gear are in a state of meshing with the surplus portion.   The power take-out device according to claim 2, wherein a tooth width of the take-out gear is narrower than an axial width of the surplus portion. The power transmission shaft is an output shaft of a transmission that shifts and outputs the rotational power output from an engine or motor generator as the drive source, and the male spline is formed at an output end of the output shaft. And
The power transmission cylinder is a shaft coupling coupled to an input end of a propeller shaft, and the female spline is formed at the input end of the shaft coupling;
The power take-out device according to claim 2 or 3, wherein the surplus portion is formed in the male spline in a state where the output shaft and the shaft coupling are spline-coupled.   The power take-out device according to any one of claims 1 to 4, wherein a pitch circle diameter of the take-out gear is smaller than a pitch circle diameter of the male spline. In place of the rotating shaft and the take-out gear, an endless cogged belt wound around the male spline and the driven gear is provided.
The power take-out device according to claim 1, wherein teeth arranged on an inner periphery of the cogged belt are in mesh with each of the male spline and the driven gear.

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