JP2014009651A - Hydraulic motor with speed reducer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor with a speed reducer which is equipped with a coupling structure between a fixed case of a hydraulic motor and a carrier of a speed reducing mechanism capable of sufficiently ensuring coupling force, and having excellent workability.SOLUTION: A hydraulic motor 1 with a speed reducer includes: a fixed case 4 in which a hydraulic motor mechanism 5 is disposed inside, and formed with a case side groove 45 on which a peripheral surface of a fixing pin 51 abuts on an outer peripheral surface; and a speed reducing mechanism 7 coupled to an output shaft 13 of the hydraulic motor mechanism 5. The speed reducing mechanism 7 has a second carrier 29 formed with a carrier side groove 43 on which the peripheral surface of the fixing pin 51 abuts on an inner peripheral surface of a collar portion 41. While the fixed case 4 and the second carrier 29 are superimposed, a hole 52 reaching a part of the fixed case 4 is bored on the carrier 29 from the opposite side to the fixed case 4, thereby forming the case side groove 45 and the carrier side groove 43 by simultaneous machining.

Description

  The present invention relates to a hydraulic motor with a reduction gear.

  As a technique for connecting the carrier constituting the speed reduction mechanism to the fixed case of the hydraulic motor, for example, there are those described in Patent Documents 1 and 2. The hydraulic motor with a reduction gear described in Patent Document 1 is formed with a plurality of bolt holes on the mating surfaces of the housing 12 (fixed case) of the hydraulic motor 1 and the holder 23 (carrier) of the reduction gear 2, The holder 23 is connected to the housing 12 by fastening the bolt 5 to the bolt hole from the speed reducer 2 side.

  Moreover, the hydraulic motor with a reduction gear described in Patent Document 2 is configured so that the inner peripheral surface of the flange portion of the carrier 33 is engaged with the shaft spline 3D formed on the outer peripheral surface of the motor casing 3 (fixed case). 33 is connected to the motor casing 3.

JP-A-9-257107 Japanese Patent No. 4532250

  In the reduction gear with a motor described in Patent Document 1, since the housing 12 and the holder 23 are connected at the mating surface between the housing 12 and the holder 23, the following problems may occur.

  First, since the area of the mating surface is determined by the size and shape of the housing 12 and the holder 23 and is limited, a large number of connecting bolts 5 cannot be provided. When forming bolt holes on the mating surfaces, it is necessary to form the bolt holes sufficiently inside the outer periphery of the housing 12 and the holder 23 from the viewpoint of strength reduction and prevention of chipping of the edge, etc. The number of bolts 5 cannot be arranged.

  Further, the force applied to the bolt 5 increases as the distance from the center of the housing 12 or the holder 23 increases. Therefore, it is preferable to arrange the bolts 5 as far as possible from the center.

  In the reduction gear with a motor described in Patent Document 2, the carrier 33 is connected to the outer peripheral surface of the motor casing 3 by the shaft spline 3D, so that the above-described problem does not occur. However, in the case of spline coupling, it takes time to process the spline. In addition, a dedicated processing machine for forming splines is required. That is, when the spline coupling is adopted, there is a problem that the manufacturing unit price becomes high.

  The present invention has been made in view of the above problems, and its object is to provide a coupling structure between a fixed case of a hydraulic motor and a carrier of a speed reduction mechanism, which can sufficiently secure a coupling force and is excellent in workability. It is providing the motor with a reduction gear provided with this.

  The hydraulic motor with a speed reducer according to the present invention includes a hydraulic motor mechanism disposed therein, a fixed case in which a case side groove with which a peripheral surface of a fixed pin abuts is formed on the outer peripheral surface, and is rotatably supported by the fixed case. A rotation case; and a speed reduction mechanism that is disposed inside the rotation case and coupled to the output shaft of the hydraulic motor mechanism. The speed reduction mechanism includes a sun gear connected to the output shaft, an output gear to which the output of the hydraulic motor mechanism is transmitted from the sun gear, and a carrier side groove with which a peripheral surface of the fixed pin abuts in the flange portion. And a carrier formed on a peripheral surface for rotatably holding the output gear. In the state where the fixed case and the carrier are overlapped, a hole reaching the part of the fixed case is opened in the carrier from the side opposite to the fixed case, so that the case side groove and the carrier side groove Are formed by simultaneous processing. The carrier is connected to the fixed case by inserting the fixing pin into a space formed by the case side groove and the carrier side groove.

  According to the present invention, since the fixing pins are arranged on the outer peripheral surface of the fixing case, more fixing pins can be provided than in the case where the fixing pins are provided on the mating surface of the fixing case and the carrier. Moreover, since the case side groove and the carrier side groove are formed simultaneously, it is possible to suppress the misalignment between the case side groove into which the fixing pin is inserted and the carrier side groove. As a result, a sufficient coupling force between the fixed case and the carrier can be secured. Also, the carrier can be drilled to form the case side groove and the carrier side groove with a general processing machine. That is, the connection structure between the fixed case and the carrier in the present invention is excellent in workability in the production.

It is sectional drawing which shows the hydraulic motor with a reduction gear which concerns on one Embodiment of this invention. It is the schematic which shows the AA cross section of FIG. It is a single-piece figure of the carrier shown in FIG. It is sectional drawing which shows the state when the fixed case and carrier shown in FIG. 1 are processed simultaneously, and the state which the fixed case and the carrier connected. It is the A section enlarged view of FIG. It is sectional drawing which shows the other form when processing a fixing case and a carrier simultaneously. It is the A section enlarged view of FIG.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. 1-5 is a figure for demonstrating the hydraulic motor 1 with a reduction gear.

(Hydraulic motor with reduction gear)
As shown in FIG. 1, the hydraulic motor 1 with a speed reducer has a hydraulic motor 2 and a speed reducer 3 (planetary speed reducer). The hydraulic motor 1 with a reduction gear is used for a traveling device in a construction vehicle such as a hydraulic excavator, for example. In addition, it is not limited to the use for construction vehicles.

(Hydraulic motor)
The hydraulic motor 2 includes a hydraulic motor mechanism 5 and a fixed case 4 that houses the hydraulic motor mechanism 5 therein.

  The fixed case 4 is a bottomed cylindrical casing, and a hole 12 through which the output shaft 13 of the hydraulic motor mechanism 5 is inserted is provided in the center portion of the bottom portion 11.

  The hydraulic motor mechanism 5 is a motor portion having the output shaft 13 described above, and is disposed inside the fixed case 4. The output of the hydraulic motor mechanism 5 is transmitted to the speed reducer 3 by the output shaft 13. In addition, as the hydraulic motor mechanism 5, a well-known thing can be used and the description is omitted in this application.

(Decelerator)
The speed reducer 3 includes a speed reduction mechanism 7 (a planetary speed reduction mechanism) and a rotating case 6 that accommodates the speed reduction mechanism 7 therein.

  The rotating case 6 is a hollow cylindrical casing, and the bottom 11 side of the fixed case 4 is inserted from one opening side thereof. The other opening is closed by a lid 21. The rotary case 6 is rotatably supported by the fixed case 4 via bearings 22a and 22b arranged between the outer periphery of the fixed case 4 and the inner periphery of the rotary case 6.

  The speed reduction mechanism 7 is disposed inside the rotary case 6 and is connected to the output shaft 13 of the hydraulic motor mechanism 5, and includes a first sun gear 24 (sun gear), a first planetary gear 25, and a first carrier 26. , Second sun gear 27, second planetary gear 28 (output gear), second carrier 29 (carrier), and internal teeth 30. The speed reduction mechanism 7 transmits the output of the hydraulic motor mechanism 5 while reducing the rotation speed, and finally drives the rotation case 6 to rotate, thereby causing a sprocket (not shown) attached to the flange portion 31 of the rotation case 6. ) To drive a non-driving part (not shown).

  The first sun gear 24 is connected to the end of the output shaft 13 of the hydraulic motor mechanism 5 and rotates together with the output shaft 13.

  A plurality of first planetary gears 25 are arranged around the first sun gear 24 and mesh with the first sun gear 24. These first planetary gears 25 are rotatably held with respect to the first carrier 26. Thereby, each 1st planetary gear 25 revolves around the 1st sun gear 24, rotating. In addition, each first planetary gear 25 is arranged to mesh with an internal tooth 30 formed on the inner periphery of the rotating case 6.

  The first carrier 26 is a member that rotatably holds the first planetary gear 25 and is spline-coupled to the second sun gear 27. The second sun gear 27 is a cylindrical member into which the output shaft 13 is inserted, and meshes with the plurality of second planetary gears 28 in addition to the first carrier 26.

  The second planetary gear 28 (output gear) outputs the output of the hydraulic motor mechanism 5 transmitted from the first sun gear 24 through the first planetary gear 25, the first carrier 26, and the second sun gear 27 to the internal gear. This is a gear that is transmitted to the rotary case 6 via 30.

  The second planetary gear 28 is rotatably held with respect to the second carrier 29. Further, the second planetary gear 28 is arranged so as to mesh with the internal teeth 30.

  The second carrier 29 is a member that rotatably holds the second planetary gear 28. Although described in detail later, the second carrier 29 is connected to the fixed case 4 of the hydraulic motor 2 so that the second carrier 29 is not displaced relative to the fixed case 4 at least in the circumferential direction of the fixed case 4. A plurality of column portions 53 that rotatably hold the second planetary gear 28 are formed on the end surface 29 a (see FIG. 3) of the second carrier 29 on the opposite side to the fixed case 4. 3 is a view of the second carrier 29 shown in FIG. 3 when the second carrier 29 in FIG. 1 is viewed in the direction of arrow B shown in FIG.

(Movement of each gear of the speed reduction mechanism)
The operation of the speed reducer 3 configured as described above will be described. When the hydraulic motor mechanism 5 disposed inside the fixed case 4 rotates, the first sun gear 24 coupled to the output shaft 13 rotates, and each first planet gear meshed with the first sun gear 24 is rotated. While the gear 25 meshes with the internal teeth 30, a revolving motion is performed around the first sun gear 24. As the first planetary gear 25 revolves, the first carrier 26 rotates, and the second sun gear 27 splined with the first carrier 26 rotates. As the second sun gear 27 rotates, each second planetary gear 28 rotatably held by the second carrier 29 rotates (spins), whereby the second planetary gear 28 and the internal teeth 30 are rotated. The rotating case 6 is rotationally driven through the meshing.

(Connection between fixed case and carrier)
The connection between the fixed case 4 and the second carrier 29 will be described in detail.

  The fixed case 4 and the second carrier 29 include a plurality of carrier-side grooves 43 formed on the inner peripheral surface 42 of the flange 41 of the second carrier 29 and a plurality of cases formed on the outer peripheral surface 44 of the bottom 11 of the fixed case 4. They are connected by a cylindrical fixing pin 51 inserted into a space formed by the side groove 45. As shown in FIG. 1, the flange 41 of the second carrier 29 is an annular flange extending from the outer periphery of the second carrier 29 in the axial direction of the output shaft 13 and toward the hydraulic motor mechanism 5.

<Formation of carrier side groove and case side groove>
First, a method for forming the carrier side groove 43 and the case side groove 45 will be described with reference to FIGS. The right view (F4a) in FIG. 4 is a cross-sectional view showing the processing state of the fixed case 4 and the second carrier 29, and the left view (F4b) in FIG. FIG. 6 is a cross-sectional view showing a state in which the second carrier 29 is connected by a fixing pin 51. FIG. 5 is an enlarged view of a portion A in FIG.

  On the inner side portion of the second carrier 29, an annular convex portion 61 is provided that protrudes toward the fixed case 4 that is overlapped. In addition, an annular concave portion 62 that abuts the convex portion 61 is provided at the end of the inner portion (hole 12 portion) in the bottom portion 11 of the fixed case 4. The convex portion 61 and the concave portion 62 form an axis adjustment mechanism for aligning the axis of the second carrier 29 and the axis of the fixed case 4.

  The recess 62 provided in the fixed case 4 has a conical shape. The tapered surface 62 a is inclined at an angle of α degrees with respect to the axial direction of the fixed case 4. The value of α is, for example, 30 or more and less than 90. In the present embodiment, the taper surface is 30 degrees. Note that 10 ≦ α <90 may be satisfied, and furthermore, 0 <α <90 may be satisfied.

  The outer peripheral surface of the convex portion 61 provided on the second carrier 29 is also a tapered surface 61a. The inclination angle of the tapered surface 61 a with respect to the axial direction of the second carrier 29 is the same as the inclination angle (α degree) of the tapered surface 62 a of the concave portion 62 of the fixed case 4.

  Here, as shown in the right side of FIG. 4, when the second carrier 29 is superimposed on the bottom 11 of the fixed case 4, the concave portion 62 of the fixed case 4 and the convex portion 61 of the second carrier 29. Thus, the convex portion 61 (second carrier 29) and the concave portion 62 (fixed case 4) are formed so that the fixed case 4 and the second carrier 29 are in contact with each other. That is, when the second carrier 29 is superimposed on the bottom 11 of the fixed case 4, for example, a gap S is formed between the fixed case 4 and the second carrier 29 in the axial direction of the fixed case 4. In the direction orthogonal to the axial direction of the fixed case 4, there is a gap between the outer peripheral surface 44 of the bottom 11 of the fixed case 4 and the inner peripheral surface 42 of the flange 41 of the second carrier 29. Since the tapered surface 62a of the concave portion 62 and the tapered surface 61a of the convex portion 61 have the same inclination angle, there is no gap between the tapered surface 62a and the tapered surface 61a. Surface contact.

  When the second carrier 29 is superimposed on the bottom 11 of the fixed case 4 by the concave portion 62 and the convex portion 61 (axial center adjusting mechanism), the axis of the second carrier 29 and the axis of the fixed case 4 are Match.

  In this way, the fixed case 4 and the second carrier 29 are overlapped with the same axis, and the fixed case 4 and the second carrier 29 are fixed by the screw rod 63 and the nut 64, for example. In this state, a plurality of holes 52 reaching a part of the fixed case 4 are made perpendicular to the second carrier 29 from the side opposite to the fixed case 4. As shown in FIG. 3, in this embodiment, the holes 52 are opened between the pillar portions 53 of the second carrier 29 (in this embodiment, a total of 15 holes 52 are opened).

  By making this hole 52, the carrier side groove 43 and the case side groove 45 are formed simultaneously. That is, the diameter of the hole 52 and the diameter of the hole formed by the carrier side groove 43 and the case side groove 45 are naturally equal.

<Assembly of fixed case and carrier>
In assembling the second carrier 29 to the fixed case 4, first, a lock washer 32 having a predetermined thickness is attached to the annular groove 33 provided on the outer periphery of the bottom 11 of the fixed case 4. Then, the second carrier 29 is overlaid on the bottom 11 of the fixed case 4, and the fixed pin 51 is inserted into the space formed by the case side groove 45 and the carrier side groove 43 to connect the fixed case 4 and the second carrier 29. To do. The fixing pin 51 may be inserted by press-fitting or loose insertion. Thereby, the second carrier 29 is connected to the fixed case 4 so as not to be displaced at least in the circumferential direction of the fixed case 4.

(Action / Effect)
According to the present invention, since the fixing pins are arranged on the outer peripheral surface of the fixing case, more fixing pins can be provided than the hydraulic motor with a reduction gear described in Patent Document 1. Moreover, since the case side groove and the carrier side groove are formed simultaneously, it is possible to suppress the misalignment between the case side groove into which the fixing pin is inserted and the carrier side groove. Thereby, the dispersion | variation in the force which acts on several fixing pins is suppressed to the minimum. As a result, it is possible to minimize a decrease in durability due to a large force acting on the specific fixing pin and being worn. As a result, a sufficient coupling force between the fixed case and the carrier can be secured.

  Also, the carrier can be drilled to form the case side groove and the carrier side groove with a general processing machine. That is, the connection structure between the fixed case and the carrier in the present invention is excellent in workability in the production.

  In the present embodiment, holes for forming the case side groove and the carrier side groove are formed between the carrier pillars. Since this part is a thin part, processing is easy. That is, the workability can be improved.

  Moreover, in this embodiment, the said hole is opened in the state which match | combined the axial center of the carrier and the axial center of the fixed case. Thereby, in the state which connected the carrier to the fixing case using the fixing pin, the axis of the carrier coincides with the axis of the fixing case. Thereby, when components, such as a gear in a reduction gear, rotate, it is possible to prevent the gears from being uniformly meshed, and to prevent the product life from varying.

  In addition, since an axis adjustment mechanism for aligning the axis of the carrier and the axis of the fixed case is provided, the axis can be easily aligned.

  In this embodiment, the shaft center adjusting mechanism is formed in a part of the carrier and the fixed case, such as an annular convex part formed in the inner part of the carrier and a conical concave part formed in the inner part of the fixed case. Therefore, there is no need for separate parts for adjusting the shaft center. Accordingly, the manufacturing cost can be reduced, and the axis alignment can be performed more easily.

  Further, in this embodiment, a lock washer is attached to the outer periphery of the bottom portion of the fixed case so that the annular convex portion formed on the carrier and the conical concave portion formed on the fixed case do not contact in the connected state. Has been. As a result, since these convex portions and concave portions do not wear, it is not necessary to finely correct the shape of the convex portions and concave portions for axial alignment even when repeated disassembly and assembly.

(Modification)
The fixing pin 51 does not necessarily have a cylindrical shape. Similarly, the inner peripheral surfaces of the case side groove 45 and the carrier side groove 43 with which the peripheral surface of the fixing pin 51 abuts are not necessarily circular (substantially semicircle). For example, the fixing pin 51 having an elliptical column shape or a quadrangular column shape may be used. In this case, since the case-side groove 45 and the carrier-side groove 43 also have a shape in surface contact with the fixing pin 51, the shape of the hole 52 for simultaneously forming these grooves is not a perfect circle but an ellipse, a rectangle, or the like.

(Other forms of shaft center adjustment mechanism)
Another embodiment of the shaft center adjusting mechanism will be described with reference to FIGS. In the present embodiment, the shaft center adjusting mechanism is formed on the outer peripheral portion of the fixing case 4 where the fixing pin 51 is disposed and on the inner peripheral portion of the second carrier 29 where the fixing pin 51 is disposed.

  Specifically, the outer peripheral surface of the bottom 11 of the fixed case 4 is a tapered surface 44a (case side tapered surface), and the inner peripheral surface of the flange 41 of the second carrier 29 is along the tapered surface 44a (case side tapered surface). A tapered surface 42a (carrier-side tapered surface) is used. The taper surface 44 a (case side taper surface) and the taper surface 42 a (carrier side taper surface) form an axis adjustment mechanism that aligns the axis of the second carrier 29 and the axis of the fixed case 4.

  A tapered surface 44 a formed on the outer periphery of the bottom portion of the fixed case 4 is an annular tapered surface that is reduced in diameter toward the second carrier 29 in the axial direction of the fixed case 4. The tapered surface 44 a is inclined at an angle of β degrees with respect to the axial direction of the fixed case 4. The value of β is, for example, 1 or more and less than 30. In the present embodiment, the taper surface is 3 degrees. It may be 0 <β <30.

  The tapered surface 42 a formed on the inner periphery of the flange portion 41 of the second carrier 29 is an annular tapered surface that expands toward the fixed case 4 in the axial direction of the second carrier 29. The inclination angle of the tapered surface 42 a with respect to the axial direction of the second carrier 29 is the same as the inclination angle (β degrees) of the tapered surface 44 a of the fixed case 4.

  As shown in FIGS. 6 and 7, when the second carrier 29 is overlapped with the bottom 11 of the fixed case 4, the tapered surface 44 a formed on the fixed case 4 and the taper formed on the second carrier 29. The second carrier 29 and the fixed case 4 are formed so that the fixed case 4 and the second carrier 29 are in contact only with the surface 42a. That is, when the second carrier 29 is superimposed on the bottom 11 of the fixed case 4, there is a gap between the fixed case 4 and the second carrier 29 in the axial direction of the fixed case 4. Since the taper surface 44a and the taper surface 42a have the same inclination angle, there is no gap between these surfaces, and the taper surface 44a and the taper surface 42a are in surface contact.

  When the second carrier 29 is superposed on the bottom 11 of the fixed case 4 by these tapered surfaces 44a and 44b (axial center adjusting mechanism), the axis of the second carrier 29 and the axis of the fixed case 4 can be easily arranged. Can match.

(Action / Effect)
According to the present embodiment, since the contact area of the conical surface (tapered surface) can be increased, backlash at the time of axial alignment is suppressed. For this reason, it is easier to align the center of the carrier and the fixed case. Furthermore, since the part where the force from the blade of the tool acts is in contact (tapered surfaces 44a and 44b) at the time of drilling (simultaneous machining of the case side groove and the carrier side groove), the backlash at the time of drilling is also small. It can be suppressed. That is, according to this shaft center adjusting mechanism, the workability in manufacturing can be further improved.

  In addition, since the contact area of the conical surface (tapered surface) can be increased, there is an effect that the inclination angle of the tapered surface can be made smaller than that of the previous embodiment.

DESCRIPTION OF SYMBOLS 1 Hydraulic motor with reduction gear 2 Hydraulic motor 3 Reduction gear 4 Fixed case 5 Hydraulic motor mechanism 6 Rotating case 7 Reduction mechanism 13 Output shaft 24 1st sun gear (sun gear)
28 Second planetary gear (output gear)
29 Second career (carrier)
41 flange 42 inner peripheral surface 43 carrier side groove 44 outer peripheral surface 45 case side groove 51 fixing pin 52 hole

Claims (6)

A fixed case in which a hydraulic motor mechanism is arranged and a case side groove with which the peripheral surface of the fixed pin abuts is formed on the outer peripheral surface;
A rotating case rotatably supported by the fixed case;
A speed reduction mechanism disposed inside the rotating case and coupled to the output shaft of the hydraulic motor mechanism;
With
The deceleration mechanism is
A sun gear coupled to the output shaft;
An output gear to which the output of the hydraulic motor mechanism is transmitted from the sun gear;
A carrier side groove with which the peripheral surface of the fixing pin abuts is formed on the inner peripheral surface of the flange, and the carrier that rotatably holds the output gear;
Have
In the state where the fixed case and the carrier are overlapped, a hole reaching the part of the fixed case is opened in the carrier from the side opposite to the fixed case, so that the case side groove and the carrier side groove Are formed by simultaneous processing,
A hydraulic motor with a reduction gear, wherein the carrier is connected to the fixed case by inserting the fixing pin into a space formed by the case side groove and the carrier side groove. In the hydraulic motor with a reduction gear according to claim 1,
On the end surface of the carrier on the side opposite to the fixed case, a plurality of column portions that rotatably hold the output gear are formed,
The hydraulic motor with a reduction gear, wherein the hole is formed between the pillar portions. In the hydraulic motor with a reduction gear according to claim 1 or 2,
The hydraulic motor with a reduction gear, wherein the hole is formed in a state where the axis of the carrier and the axis of the fixed case are aligned. In the hydraulic motor with a reduction gear according to claim 3,
A hydraulic motor with a reduction gear, characterized in that an axis adjustment mechanism for aligning the axis of the carrier and the axis of the fixed case is provided. In the hydraulic motor with a reduction gear according to claim 4,
The axis adjusting mechanism is
An annular projection formed on the carrier so as to protrude toward the fixed case at the inner portion of the carrier;
A concave portion that abuts against the convex portion formed on the inner portion of the fixed case;
A hydraulic motor with a speed reducer characterized by comprising: In the hydraulic motor with a reduction gear according to claim 4,
The axis adjusting mechanism is
A case-side tapered surface formed on the outer peripheral surface of the fixed case and having a diameter reduced toward the carrier;
A carrier-side taper surface that is formed on the inner peripheral surface of the flange portion of the carrier so as to be along the case-side taper surface, and expands toward the fixed case;
A hydraulic motor with a speed reducer characterized by comprising:

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