JP2011212772A - Method for machining differential case inner surface and means for machining the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for machining a differential case inner surface capable of eliminating fixing work of a machining tool and a mounting tool in a differential case by allowing the machining tool to be put in and out from the inside of the differential case through the one hole thereof and miniaturizing a machining device for machining the inner surface of the differential case, and also to provide a means for machining the inner surface of the differential case.SOLUTION: The means 10 for machining the differential case inner surface is comprised of: the machining tool 18 comprising a main shaft part 12, a protruding tip part 14 laterally protruding from the main shaft part 12, and a counterboring tool 16 fixed to the protruding tip part 14; and a guide bush 22 movably fitted to the main shaft part 12. The counterboring tool 16 is inserted into an inner space 38 from the pinion hole 44 of the differential case 34 and the guide bush 22 is fitted to the pinion hole 44. Thereafter, the counterboring tool 16 is made to contact with the spherical seat 46 of the differential case 34 while the machining tool 18 is rotated, and the spherical seat 46 is machined.

Description

  The present invention relates to a differential case inner surface processing method and a differential case inner surface processing means for processing opposing inner surfaces of a differential case of a differential gear device.

  A differential gear device that is a power transmission mechanism includes a pair of side gears that are operating large gears and a pair of pinions that are operating small gears in a differential case. On the inner surface of the differential case, face seats that contact the operating large gears at positions facing each other and face seats that respectively contact the operating small gears at positions facing each other are formed by cutting. A conventional technique for processing the inner surface of the differential case is disclosed in Patent Document 1.

  In order to cut a pair of face seats facing each other on the inner surface of the differential case, a cutting tool having cutting blades on both sides is provided inside the differential case, and a pressing tool is inserted into the differential case from both sides to cut the inside. A pair of pressing tools are connected and fixed to the tool. The pressing tool on one side is moved in the axial direction by the NC driving means, one side of the cutting tool is brought into contact with the face seat of the differential case, and the pressing tool and the cutting means are rotated by the NC driving means to move the face seat on the one side. Process. Thereafter, the other side pressing tool is moved in the axial direction by the NC driving means, the other side of the cutting tool is brought into contact with the other side seat, the pressing tool and the cutting tool are rotated by the NC driving means, and the other side pressing tool is rotated. The face seat is processed. Thus, a pair of face seats facing each other on the inner surface of the differential case are cut.

JP2008-13561

  A known processing apparatus for processing the inner surface of the differential case has a drawback that it takes time to fix the cutting tool provided inside the differential case and the pair of pressing tools inserted into the differential case from the outside. Furthermore, in the conventionally known processing apparatus, a pressing tool and a movable means are provided on one outer side centering on the differential case, and a pressing tool and a hydraulic cylinder are provided on the other outer side centering on the differential case. As a result, the overall length of the apparatus becomes large and the entire apparatus becomes large.

  The present invention enables a machining tool to be taken in and out from one hole of the differential case, thereby eliminating the fixing work between the machining tool and the mounting tool in the differential case, and machining the inner surface of the differential case. An object of the present invention is to provide a differential case inner surface processing method and a differential case inner surface processing means capable of downsizing the processing apparatus.

  A differential case inner surface processing method according to the present invention is a differential case inner surface processing method for processing a spherical seat or a plane seat of a differential case in which a pair of pinion holes and a pair of drive holes are formed to connect the internal space and the outside. A long rod-shaped main shaft portion having a circular cross section, a projecting tip portion that is provided at the front end of the main shaft portion and protrudes laterally from the axial direction of the main shaft portion, and a position side exposed to the main shaft portion side A counterbore tool for cutting the spherical seat or the flat seat of the differential case, a cylindrical inner space, and the main shaft portion. And a fitting outer wall portion that can be fitted to the pinion hole or the drive hole and can be moved relative to the main shaft portion while maintaining a fitted state. Guide bush And the pinion hole or the drive hole formed in the differential case by using a differential case inner surface processing means comprising: a portion communicating with the protruding tip portion in the main shaft portion, the protruding tip portion, and the counterbore tool; The counterbore processing tool is inserted into the inner space through the one hole, the axial direction of the main shaft portion and the axial direction of one hole through which the main shaft portion is inserted, and the guide bush A fitting outer wall portion is fitted into the one hole, the counterbore tool is brought into contact with the spherical seat or the flat seat, and then the differential case inner surface processing means is rotated to rotate the differential seat tool by the counterbore tool. Alternatively, the planar seat is cut.

  The differential case inner surface processing means according to the present invention is a differential case inner surface processing means for processing a spherical seat or a plane seat of a differential case in which a pair of pinion holes and a pair of drive holes are formed to connect the internal space and the outside. A long rod-shaped main shaft portion having a circular cross section, a projecting tip portion that is provided at the front end of the main shaft portion and protrudes laterally from the axial direction of the main shaft portion, and a position side exposed to the main shaft portion side A counterbore tool for cutting the spherical seat or the flat seat of the differential case, a cylindrical inner space, and the main shaft portion. And a fitting outer wall portion that can be fitted to the pinion hole or the drive hole and can be moved relative to the main shaft portion while maintaining a fitted state. Guide bush A portion of the main shaft portion that communicates with the protruding tip portion, the protruding tip portion, and the counterbore processing tool pass through the pinion hole or the drive hole formed in the differential case, and the internal space. It is characterized by having a shape and a size that can be inserted into the housing.

  According to the differential case inner surface processing method of the present invention, it is possible to allow a processing tool to be taken into and out of the internal space of the differential case through a hole in the differential case. As a result, in the present invention, it is possible to omit the conventionally required work of fixing the processing tool provided in the differential case to the fixture in the differential case, and it is possible to improve the work efficiency. In addition, conventionally, in order to cause the fixture to be fixed to the processing tool to protrude on both sides of the differential case, it is necessary to provide means for holding and driving the respective fixtures on both sides of the differential case, and the entire apparatus is large. On the other hand, in the present invention, since the machining tool is simply put into and out of the differential case from one hole, the entire machining apparatus can be reduced in size.

The differential case inner surface processing means of the present invention includes a processing tool comprising a main shaft portion, a front end projecting portion projecting laterally from the main shaft portion on the front end side thereof, and a counterboring tool fixed to the front end projecting portion, and an outer side of the main shaft portion. It is composed of a cylindrical guide bush which is fitted to the main shaft portion without movement and is movable. With this configuration, the tip position of the machining tool (the contact position between the protruding tip portion, the counterbore tool fixed to the protruding tip portion, and the protruding tip portion in the main shaft portion) is a single hole (pinion hole or drive hole). ) Can be inserted into the inner space of the differential case, the counterbore processing tool is brought into contact with the face seat on the inner surface of the differential case, and the face seat on the inner surface of the differential case can be processed with the counterbore processing tool. Furthermore, when machining the face seat on the inner surface of the differential case with a counterbore tool, the main shaft of the processing tool can be attached to the guide bush or differential case by fitting the fitting outer wall of the guide bush to the pinion hole or drive hole without blurring. On the other hand, it can be rotated without blurring, and can be processed into a spherical seat or flat seat with desired accuracy.

It is a front view which shows one Example of the differential case inner surface processing means based on this invention. It is sectional drawing which shows the state before inserting the processing tool of the differential case inner surface processing means of FIG. 1 in a differential case. It is sectional drawing which shows the state which inserts a processing tool in a differential case from the state of FIG. 2, and cuts the spherical seat in a differential case. It is a fragmentary sectional view which shows the state which inserted the counterbore processing tool for forming a plane seat in the differential case.

  Next, the present invention will be described with reference to the drawings. 1 is a front view showing an embodiment of a differential case inner surface processing means according to the present invention, FIG. 2 is a sectional view showing a state before the processing tool of the differential case inner surface processing means of FIG. 1 is inserted into the differential case, and FIG. It is sectional drawing which shows the state which inserts a processing tool in a differential case from the state of FIG. 2, and cuts the face seat in a differential case. The differential case inner surface processing means 10 according to the present invention includes an elongated rod-like main shaft portion 12 having a circular cross section, a projecting tip portion 14 projecting laterally with respect to the axial direction at the tip portion of the main shaft portion 12, and a projecting tip portion thereof. 14 has a counterbore processing tool 16 made of, for example, a carbide tip, and a processing tool 18 made of it.

The protruding tip 14 that bends in the lateral direction with respect to the axial direction of the main shaft portion 12 is preferably bent into an L shape at an angle close to about 90 degrees with respect to the main shaft portion 12, but is not limited to this angle. The main shaft portion 12 and the projecting tip portion 14 are desirably formed integrally, but are not limited thereto. The counterbore processing tool 16 is fixed to the L-shaped inner side (side exposed to the main shaft portion 12) of the protruding tip portion 14. The counterbore tool 16 is fixed to the protruding tip 14 by brazing, for example. The cutting blade portion 20 (shown in FIGS. 1 to 3) on the outer surface of the counterbore processing tool 16 is exposed toward the main shaft portion 12 side. The surface of the cutting blade portion 20 is formed in an R shape (curved shape) in order to process a spherical seat (described later).

The differential case inner surface processing means 10 further has a cylindrical shape, and has an inner space fitted with the main shaft portion 12 and a guide bush 22 movable with respect to the main shaft portion 12. The guide bush 22 includes a small-diameter portion 24 as a fitting outer wall portion having a relatively small outer diameter on the protruding tip portion 14 side, and a large-diameter portion 26 having a relatively large outer diameter on the side opposite to the protruding tip portion 14 side. The step portion 28 is provided between the small diameter portion 24 and the large diameter portion 26. In a state where all or part of the internal space of the cylindrical guide bush 22 is fitted to the outer surface of the main shaft portion 12, the main shaft portion 12 becomes the guide bush 22 even if the main shaft portion 12 moves relative to the guide bush 22. Set so that it does not blur.

As shown in FIG. 1, a tool holder 30 that detachably holds the main shaft portion 12 of the differential case inner surface processing means 10 is attached to a rotation driving means 32, and the processing tool 18 (main shaft portion) is attached by the rotation driving means 32. 12) is rotated. The rotation driving means 32 is movable in the X and Z directions by a driving device (not shown) such as an NC driving means. That is, the processing tool 18 (main shaft portion 12) can be moved in the X direction or the Z direction by, for example, NC driving means, and is rotated by the rotation driving means 32.

Japanese Patent Application Laid-Open No. 2001-205512 discloses a structure in which the guide bush 22 is held and fixed to the tool holder 30 or released. The structure in which the guide bush 22 is fixed to or released from the tool holder 30 is preferably the one shown in Japanese Patent Application Laid-Open No. 2001-205512, but is not limited thereto.

  2 and 3, the differential case 34 whose inner surface is processed has a main body 36 and an internal space 38 inside thereof. The main body 36 has a front drive hole 40 that connects the internal space 38 and the outside, and a rear side that is arranged on the same straight line as the front drive hole 40 and connects the internal space 38 and the outside. A drive hole 42 is formed. The main body 36 is further formed with a pair of pinion holes 44 that connect the internal space 38 and the outside. The pair of pinion holes 44 are arranged on the same straight line. The hole diameters of the drive holes 40 and 42 are set larger than the hole diameter of the pinion hole 44.

  On the inner surface of the differential case 34 on the inner space 38 side, a spherical seat 46 is formed on the wall surface around the pinion hole 44, and a flat seat 48 is formed on the wall surface around the drive holes 40, 42. The counterbore processing tool 16 shown in FIGS. 1 to 3 is for processing the spherical seat 46 on the inner surface around the pinion hole 44 of the differential case 34. The tip portion of the processing tool 18 (the contact position between the protruding tip portion 14, the counterbore tool 16 fixed to the protruding tip portion 14, and the protruding tip portion 14 in the main shaft portion 12) can be inserted into the pinion hole 44. Is set to

Next, a procedure for processing the spherical seat 46 will be described. First, as shown in FIG. 2, the tip portion of the processing tool 18 (the protruding tip portion 14, the counterbore tool 16 fixed to the protruding tip portion 14, and the protruding tip portion 14 in the main shaft portion 12 and the communication position) It is arranged outside the pinion hole 44 of the differential case 34, and the machining tool 18 is moved in the X and Z directions by an NC drive means (not shown) or the like, and the tip of the machining tool 18 is directed to one pinion hole 44 of the differential case 34. Insert. The tip portion of the processing tool 18 is then placed in the internal space 38 of the differential case 34 as shown in FIG. Description of the operation of inserting the tip end portion of the processing tool 18 from the pinion hole 44 into the internal space 38 of the differential case 34 is omitted.

  After the tip portion of the processing tool 18 is put into the internal space 38 of the differential case 34 from the pinion hole 44, the axial direction of the main shaft portion 12 of the processing tool 18 and the axial direction of the pinion hole 44 of the differential case 34 are matched. Thereafter, as shown in FIG. 3, the guide bush 22 is slid along the main shaft portion 12 of the processing tool 18, and the small diameter portion 24 that is the fitting outer wall portion of the guide bush 22 is fitted into the pinion hole 44. At this time, the step portion 28 of the guide bush 22 is brought into contact with the differential case 34 to position the guide bush 22. In a state where the small diameter portion 24 of the guide bush 22 and the pinion hole 44 are fitted, the size of the guide bush 22 and the size of the pinion hole 44 are set in advance so that the guide bush 22 does not shake with respect to the pinion hole 44. .

After the tip portion of the processing tool 18 is inserted into the internal space 38 of the differential case 34, the spherical seat 46 of the differential case 34 is processed. At this time, the processing tool 18 (the counterbore processing tool 16) is rotated, The processing tool 18 is moved in the Z direction in FIG. Thereafter, the cutting blade portion 20 of the counterbore processing tool 16 contacts the spherical seat 46 of the differential case 34 in a rotated state, and the spherical seat 46 of the differential case 34 is processed into a desired shape by the cutting blade portion 20 of the counterbore processing tool 16. .

After processing one spherical seat 46 of the differential case 34, the guide bush 22 is removed from the pinion hole 44, and the tip portion of the processing tool 18 is removed from the pinion hole 44. Thereafter, the tip of the machining tool 18 is inserted into the inner space 38 of the differential case 34 from the other pinion hole 44, the guide bush 22 is fitted into the pinion hole 44, and the counterbore tool 16 of the machining tool 18 is rotated. In this state, the spherical seat 46 is brought into contact with the differential case 34 and the other spherical seat 46 is processed into a desired shape by the counterbore processing tool 16.

  As described above, according to the differential case inner surface processing method of the present invention, the processing tool can be inserted into and removed from the internal space 38 of the differential case 34 from one hole of the differential case 34, and the face seat around the single hole is processed. It is possible to do. In the present invention, the counterbore processing tool 16 for processing the spherical seat 46 is fixed in advance to the protruding tip 14 outside the differential case 38. That is, according to the present invention, the machining tool is provided in the internal space in the differential case as in the prior art, and the machining tool provided in the differential case does not require the work of attaching the attachment tool from both sides in the differential case, thereby improving the machining efficiency. Can do. Further, according to the present invention, it is not necessary to arrange a tool for operating the attachment tool on both sides of the pair of holes of the differential case, and the processing apparatus can be reduced in size.

  In the above description, the spherical seat 46 around the pinion hole 44 has been processed. On the other hand, when processing the plane seat 48 around the drive holes 40 and 42, a differential case inner surface processing means 50 as shown in FIG. 4 is used. The differential case inner surface processing means 50 is fixed to the main shaft portion 52 having a circular cross section, a projecting tip portion 54 projecting laterally with respect to the axial direction at the tip portion of the main shaft portion 52, and the projecting tip portion 54. And a machining tool 58 composed of a counterbore machining tool 56.

Further, the differential case inner surface processing means 50 has a cylindrical shape and is just fitted to the outer surface of the main shaft portion 52 and is movable with respect to the main shaft portion 52. Even if relative movement occurs between the main shaft portion 52, the main shaft portion A guide bush 60 is provided so as not to cause blurring with respect to 52. Each component of the differential case inner surface processing means 10 that processes the spherical seat 46 around the pinion hole 44 and each component of the differential case inner surface processing means 50 that processes the flat seat 48 around the drive holes 40 and 42 have shapes. They are the same, only different in size, and their functions are the same. However, the cutting blade portion 20 of the counterbore processing tool 16 shown in FIGS. 1 to 3 has an R shape, whereas the cutting blade portion 62 of the counterbore processing tool 56 shown in FIG. 4 has a planar shape. If the differential case inner surface processing means 50 is used, the planar seat 48 in the differential case 34 can be processed into a desired planar shape.

DESCRIPTION OF SYMBOLS 10 Differential case inner surface processing means 12 Main shaft part 14 Projection tip part 16 Counterbore processing tool 18 Processing tool 20 Cutting blade part 22 Guide bush 34 Differential case 36 Main body 38 Internal space 40 Drive hole 42 Drive hole 44 Pinion hole 46 Spherical seat 48 Plane seat 50 Differential case Inner surface machining means 52 Main shaft portion 54 Projection tip portion 56 Counterboring tool 58 Processing tool 60 Guide bush 62 Cutting blade portion

Claims (2)

  A differential case inner surface machining method for machining a spherical seat or a plane seat of a differential case in which a pair of pinion holes and a pair of drive holes are formed to connect the internal space and the outside, and a main shaft portion having a long bar shape with a circular cross section And provided at the front end of the main shaft portion, fixed to the projecting front end portion projecting laterally from the axial direction of the main shaft portion, and the projecting front end portion on the position side exposed to the main shaft portion side. A counterbore processing tool for cutting the spherical seat or the flat seat of the differential case, and a cylindrical shape, and the cylindrical inner space and the main shaft portion are fitted and fitted in the axial direction. A differential case inner surface processing means comprising: a guide bush having a fitting outer wall portion that is movable with respect to the main shaft portion without blurring while maintaining a fitted state and fitted into the pinion hole or the drive hole. The The portion of the main shaft portion that communicates with the projecting tip, the projecting tip and the counterbore tool are inserted into one of the pinion hole or the drive hole formed in the differential case. The counterbore processing tool is inserted into the internal space, the axial direction of the main shaft portion and the axial direction of one hole through which the main shaft portion is inserted match, and the fitting outer wall portion of the guide bush is set to the one piece. Fit the hole, bring the counterbore tool into contact with the spherical seat or the flat seat, and then rotate the differential case inner surface processing means to cut the spherical seat or the flat seat with the counterbore tool. The differential case inner surface processing method characterized by this.   A differential case inner surface processing means for processing a spherical seat or a plane seat of a differential case in which a pair of pinion holes and a pair of drive holes are formed to connect the internal space and the outside, and a main shaft portion having a long bar shape with a circular cross section And provided at the front end of the main shaft portion, fixed to the projecting front end portion projecting laterally from the axial direction of the main shaft portion, and the projecting front end portion on the position side exposed to the main shaft portion side. A counterbore processing tool for cutting the spherical seat or the flat seat of the differential case, and a cylindrical shape, and the cylindrical inner space and the main shaft portion are fitted and fitted in the axial direction. A guide bush having a fitting outer wall portion that is movable with respect to the main shaft portion without blurring while maintaining a combined state, and that fits into the pinion hole or the drive hole, Said bump in the part The portion that communicates with the tip, the protruding tip, and the counterbore tool have a shape and size that can be inserted into the internal space through the pinion hole or the drive hole formed in the differential case. Differential case inner surface processing means.

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