JP5037822B2 - Differential limiter - Google Patents

Description

  The present invention relates to a differential limiting device that can be used for various vehicles such as working vehicles such as agricultural machinery, construction engineering machinery, and transporting machinery, buggy vehicles, and automobiles, and particularly requires special processing. The present invention relates to a differential limiting device that can perform processing easily and accurately without reducing manufacturing costs.

  Conventionally, in various vehicles such as automobiles, various differential limits provided with a differential limiting function in a differential gear (differential gear) that can improve traction and running stability by suppressing idling of drive wheels. An apparatus (limited slip differential gear) has been proposed (see, for example, Patent Document 1).

  The differential limiting device 100 (FIG. 8) described in Patent Document 1 is for limiting the differential between the left and right driving wheels to ensure driving force, and is mounted on a small vehicle such as a buggy. ing. As shown in FIG. 7, the differential limiting device 100 is provided inside a front final assembly 104 connected to a pair of left and right front drive shafts 102 and 103 that are components of the power transmission mechanism 101.

As shown in FIG. 8, a differential case 105 that is a component of the conventional differential limiting device 100 includes a case body 106 that is integrally formed in a cup shape and a cap (not shown) that covers the opening of the case body 106. It has a two-part structure. A ring gear 107 is attached to the cap.
As shown in FIG. 8, the differential case 105 includes two types of input side blocks (cam followers) 108 and 109 that rotate integrally while sliding in the axial direction of the differential case 105 and the case groove. The left and right output cams 110 and 111 and the left output side cam 110 that can sandwich the input side blocks 108 and 109 so as to be slidable relative to each other and can rotate independently by frictional force with the input side blocks 108 and 109. A thrust washer 112 adjacent to the thrust washer 112 and a disc spring 113 adjacent to the thrust washer 112 are housed.

In the conventional differential limiting device 100, as described above, the case body 106 of the differential case 105 is integrally formed in a cup shape. For this reason, compared with the case where the case main body 106 is composed of two parts, the number of parts can be reduced and the joining process such as screw joining and welding can be eliminated. The processing man-hours can be reduced. Further, the assembly time can be shortened, and the productivity of the differential case 105 can be improved and the production cost can be reduced.
JP 2003-172431 A

  By the way, as shown in FIG. 8, the differential limiting device 100 described in Patent Document 1 includes a large number of axial grooves on the inner peripheral surface from the open end of the cup-shaped tube portion to the bottom portion of the case body 106. 106a, ..., 106a. As a method for forming these axial grooves 106a, for example, a cold forging method can be considered.

  In a normal cold forging method, it is difficult to ensure a desired dimensional accuracy in the axial groove (tooth profile) 106a provided on the inner peripheral surface of the cup-shaped cylindrical portion during forging. For this reason, by molding the case body 106 having a coarse tooth profile on the inner peripheral surface of the cup-shaped cylinder during forging, and cutting the coarse tooth profile in the case body 106 by machining after the forging, It is necessary to obtain a desired dimensional accuracy for the tooth profile.

  However, in order to form a large number of tooth shapes on the inner peripheral surface from the open end of the cylindrical portion to the bottom of the forged cup-shaped case main body 106, it is essential to insert a broach into the cylindrical portion of the case main body 106. Cutting cannot be performed with a broaching machine. For this reason, a finishing process must be performed by cutting the coarse tooth profile in the cup-shaped case body 106 one by one with a cutting tool such as a slotter.

  Thus, in the manufacturing method using cold forging, in the cup-shaped case main body 106, the final shape intended for a large number of coarse tooth shapes formed on the inner peripheral surface from the opening end of the cylindrical portion to the bottom portion is obtained. It becomes easy to be restricted by cutting and finishing by machining for finishing. Further, after the cold forging of the cup-shaped case body 106, troublesome cutting and finishing are required for a plurality of coarse tooth shapes. For this reason, the manufacturing method becomes complicated, and not only the production cost increases in mass production, but also the problem of lowering production efficiency and the design of the tooth height, tooth width and tooth profile of the axial groove 106a are restricted. There were various problems.

  Further, in the manufacturing method using cold forging, when cold forging for forming a tooth profile in the cup-shaped case main body 106 is performed, the case main body 106 has a tapered shape whose diameter increases toward the opening side. There is a tendency to deform. If the case body 106 is deformed into a tapered shape whose diameter increases toward the opening side, it is difficult to obtain a desired tooth profile in the case body 106, and the axial groove 106a in the case body 106 and the input side block 108 are obtained. 109, a problem arises in that the engagement with the projections 108a and 109a projecting from the portions corresponding to the axial grooves 106a is not ensured.

  In particular, when the differential limiting device is mounted on a vehicle larger than a small vehicle such as a buggy described in Patent Document 1, various components constituting the differential limiting device are increased in size. As a result, the cup-shaped case body 106 is also enlarged. When the cup-shaped case body 106 is increased in size, it has been difficult to perform precise forging on the axial groove 106 a provided in the case body 106. However, a technology for efficiently mass-producing this type of large cup-shaped case body 106 has not been industrialized.

  The present invention has been made to solve the above-described conventional problems, and provides a differential limiting device that is easy to mass-produce, has excellent workability, and can be processed accurately and inexpensively. The purpose is that.

The present invention has a differential case that rotates by inputting drive torque, and a plurality of cam followers that have an engaging portion that engages with the inner peripheral surface of the differential case and that is slidably disposed in the rotational axis direction of the differential case. And a cam surface formed by ridges and valleys having a predetermined pitch, and the cam surfaces are arranged opposite to each other inside the differential case with the plurality of cam followers interposed therebetween. And a second output cam member, and the first and second output cam members output a differential limiting torque proportional to the drive torque from the differential case via the plurality of cam followers. A limiting device, wherein the differential case includes a bottomed cylindrical case body having an end opening at one end, and a case cover that covers the end opening of the case body. On the inner surface, front And gear cutting are subjected have a concavo-convex portion that is toothed type created in gear-shaped case body after molding, on both sides of the longitudinal direction of the concavo-convex portion, manufacturing clearance of the annular is formed respectively The number of the set of the uneven portions is set to be twice or more the set number of the cam followers, and the engagement portion of the cam follower is set to a number of 2 or more with respect to the uneven portions. The differential limiting device is characterized in that the portion and the concavo-convex portion are engaged with each other.

  The present invention forms a bottomed cylindrical case main body having an end opening at one end by forging or casting, and after forming the bottomed cylindrical case main body by forging or casting or the like, The main feature of the present invention is to provide a concave-convex portion that is formed in a gear shape by gear cutting, which is machining, on the inner peripheral surface from the open end to the bottom of the case body.

  Here, the term tooth profile creation includes creation processing methods such as gear shaper processing and hobbing.

  According to the present invention, after the bottomed cylindrical case body is formed by forging or casting, the bottomed cylindrical case body is toothed to create a gear shape by gear cutting, thereby forming a bottomed cylindrical shape. The meshing accuracy and centering accuracy between the case main body and the cam follower can be achieved at the same time. As a result, the manufacturing process can be simplified, mass production processing is easy, and an inexpensive product with excellent quality can be obtained.

  The present invention can achieve the initial purpose by forming a tooth shape in a gear shape by gear cutting inside the case body after forming the bottomed cylindrical case body by forging or casting, etc. The present invention is not limited to this, for example, forging or casting by forming a gear-like uneven portion on the inner peripheral surface of a bottomed cylindrical case body into a rough shape during molding such as forging or casting. After forming such as the above, it is possible to create a tooth shape in a gear shape by gear cutting that is a rough machining of the rough uneven portion.

  In the present invention, the set number of concavo-convex portions of the bottomed cylindrical case body in the differential case can be set to the same number as the set number of cam followers. As a preferred example of the present invention, the inner peripheral surface of the case main body is formed in a gear shape so that the set number of the uneven portions of the case main body is an integral multiple of the set number of the cam follower, for example, an integer of 2 or more. Can be set to double. According to the present invention, for example, the set number of uneven portions of the case body can be set to an integer multiple of the set number of cam followers, so the degree of freedom in designing the gear-shaped uneven portions in the case body is increased. It becomes possible to easily set the number of teeth (number of tooth gaps), tooth height, tooth width, and the like.

  A general gear shape can be used as the outer shape of the uneven portion of the case main body. As a preferred example of the present invention, for example, the tooth profile can be constituted by a straight tooth tip surface and a semi-arc surface tooth tip fillet. As another preferred example of the present invention, for example, the tooth profile can be formed by a geometric curve such as involute or cycloid.

  As an engaging part of a cam follower, for example, a sliding surface that comes into contact with a protruding surface (tooth surface) of an uneven part in the case body, and an engaging surface that engages with a groove surface between adjacent convex parts It can comprise by the engagement protrusion part or engagement recess part which has.

  According to the present invention, the number of teeth (number of tooth gaps) of the concavo-convex portion of the case main body can be set to the same number as the engaging portion of the cam follower, but the present invention is not limited to this. In the present invention, a plurality of engaging portions of the cam follower can be provided at portions corresponding to the concave and convex portions of the differential case by creating a tooth shape on the inner peripheral surface of the case main body.

  The differential case is preferably composed of two members, for example, a bottomed cylindrical case main body and a case cover that covers an end opening of the case main body. The case body of the differential case is not particularly limited, but can be made of a casting material. As the casting material, for example, a general casting material such as a spheroidal graphite cast iron material can be used. Compared with the forging material, the casting material is an inexpensive material, and the material cost can be reduced.

  In the present invention, the inside of a bottomed cylindrical case body is toothed to create a gear shape by gear cutting, so that the manufacturing process can be simplified, mass production processing is easy, and quality is improved. An excellent and inexpensive differential limiting device can be obtained.

Preferred embodiments of the present invention will be specifically described below with reference to the accompanying drawings.
[First Embodiment]
FIG. 1 is a sectional view schematically showing a differential control apparatus according to a first embodiment of the present invention. FIG. 2 is a differential case and a cam follower of the differential control apparatus according to the first embodiment. FIG. 3 is an explanatory diagram schematically showing a configuration example of FIG. 3, and FIG. 3 is an enlarged view of a main part of FIG.

  In FIG. 1, reference numeral 10 denotes the overall configuration of a differential control device that outputs a differential limiting torque proportional to the driving torque. The differential limiting device 10 is arranged in an annular shape on a bottomed cylindrical differential case 20 that rotates by inputting drive torque from torque transmission means such as a propeller shaft (not shown) and the inner peripheral surface of the differential case 20. A plurality of cam followers 30,..., 30 that rotate in synchronization with the differential case 20, and first and second output cam members disposed opposite to each other inside the differential case 20 with the plurality of cam followers 30 sandwiched therebetween. 40, 50.

  A bottomed cylindrical differential case 20 including a plurality of cam followers 30 and first and second output cam members 40, 50 includes a circular opening formed at the center of the case bottom as shown in FIG. Is a bottomed cylindrical case body 21 having an end opening 21a having a diameter larger than the circular opening at one end on the opposite side, and a case cover 22 covering the end opening 21a of the case body 21. It is comprised by the member.

The case body 21 has a cylindrical portion 23 having a circular opening at the center of the case bottom, a bearing cylindrical portion 24 having a diameter smaller than the inner diameter of the cylindrical portion 23, and a shaft having a through-hole having a diameter smaller than the inner diameter of the bearing cylindrical portion 24. It has a stepped shape in which the penetrating part 25 is integrally formed concentrically. As shown in FIGS. 1 and 5, a substantially hexagonal flange portion 21 b is formed on the outer peripheral edge of the end opening 21 a in the cylindrical portion of the case body 21.
The bearing cylindrical portion 24 of the case main body 21 has a left (right) axle shaft (not shown) through the through hole of the shaft through portion 25 projecting outward, and the rotation shaft of the first output cam member 40. It can be splined with the portion 42. As shown in FIG. 1, an inner screw that is screwed with the outer peripheral surface of the case cover 22 is formed on the inner peripheral surface of the end opening 21 a of the case body 21. A ring gear that meshes with a propeller shaft that is gear-coupled to a torque transmission means (not shown) is formed in the flange portion 21b of the case body 21 through six mounting holes 21c, ..., 21c that are formed at predetermined intervals in the circumferential direction. It is fixed by bolting.

  As shown in FIG. 1, the case body 21 supports the first output cam member 40 via a disc spring 60, a radial needle bearing 61 and a thrust needle bearing 62 so as to be relatively rotatable.

On the other hand, as shown in FIG. 1, the case cover 22 is a shaft having a bearing cylindrical portion 26 having the same inner diameter as the bearing cylindrical portion 24 of the case main body 21 and a through hole through which a right (left) axle shaft (not shown) passes. It has a stepped shape in which the penetrating part 27 is integrally formed concentrically. On the outer peripheral surface of the bearing cylindrical portion 26 of the case cover 22, an annular mounting portion formed with an external screw that engages with the internal screw of the case body 21 is projected.
As shown in FIG. 1, the case cover 22 supports the second output cam member 50 via a spacer 63, a radial needle bearing 61 and a thrust needle bearing 62 so as to be rotatable relative to the case main body 21. .

  The cam follower 30 disposed between the first and second output cam members 40, 50 has a plurality of formed on the inner peripheral surface of the cylindrical portion 23 in the case body 21, as shown in FIGS. 1 to 3. The concavo-convex portions 28, ..., 28 are slidably engaged. According to the illustrated example, 19 cam followers 30 are provided in the number corresponding to the number of uneven portions in the case body 21, and are arranged in a ring shape at portions corresponding to the uneven portions 28.

  As shown in FIG. 1, the cam follower 30 is a side portion facing the first and second output cam members 40 and 50, and the first and second cam portions of the output cam members 40 and 50. A rectangular shape having first and second contact surfaces 31 and 32 that are in sliding contact with the cam surfaces of 41 and 51, and an engaging portion 33 that engages with an uneven portion 28 formed in the cylindrical portion 23 of the case body 21. The block body. The first and second contact surfaces 31 and 32 of the cam follower 30 have outer shapes that match the cam surfaces formed in a zigzag shape on the output cam members 40 and 50 by ridges and valleys having a predetermined pitch, respectively. There is no. As shown in FIGS. 2 and 3, the engaging portion 33 of the cam follower 30 is adjacent to a semicircular arc-shaped sliding surface 34 that comes into contact with the protruding surface (tooth surface) of the uneven portion 28 of the differential case 20. It is comprised by the protrusion engaging part 33 which has the engaging surface 35 engaged with the ditch | groove surface between convex parts. The sliding surface 34 has the same curvature as the protruding surface of the concavo-convex portion 28 of the differential case 20.

  As shown in FIG. 1, the first and second output cam members 40 and 50 disposed opposite to each other inside the differential case 20 with the plurality of cam followers 30 interposed therebetween are respectively cylindrical bearing portions of the case body 21. The first and second rotating shaft portions 42 and 52 made of a cylindrical shaft body supported in the shaft 24, and the first made of an annular body having an outer diameter larger than the outer diameter of the rotating shaft portions 42 and 52. And second cam portions 41 and 51. The inner peripheral surfaces of the cylindrical rotary shaft portions 42 and 52 are spline-fitted to the left (right) axle shaft (not shown) penetrating through the through hole of the shaft through portion 25 of the case body 21. It has become.

  In assembling the differential limiting device 10, a disc spring 60, a radial needle bearing 61, a thrust needle bearing 62, a first output cam member 40, and a ring shape are formed on the inner peripheral surface of the case body 21 according to a conventional method. , 30, the second output cam member 50, the spacer 63, the radial needle bearing 61, and the thrust needle bearing 62 are sequentially stacked and housed, and the case is attached to the inner screw of the case body 21. The outer screw of the cover 22 is screwed and fixed by fixing means (not shown). The differential limiting device 10 assembled in this way is mounted between left and right wheels in a vehicle (not shown) according to a conventional method.

  Now, when drive torque is transmitted to the differential case 20 via a ring gear that meshes with a propeller shaft that is gear-coupled to a torque transmission means (not shown), the differential case 20 rotates. When the differential case 20 rotates, the drive torque is transmitted to the cam follower 30 that is slidably engaged with the concavo-convex portion 28 of the differential case 20, and the cam follower 30 rotates synchronously with the differential case 20. When the cam follower 30 rotates, the first and second contact surfaces 31 and 32 of the cam follower 30 and the cam surfaces of the cam portions 41 and 51 of the first and second output cam members 40 and 50 are used. Drive torque is transmitted to the output cam members 40 and 50, and the first and second output cam members 40 and 50 are rotated. At the same time, a left (right) axle shaft (left and right wheels) (not shown) that is spline-fitted with the rotary shaft portions 42 and 52 of the first and second output cam members 40 and 50 is rotated.

  At this time, if relative rotation occurs between the left and right wheels (first and second output cam members), the first output cam member that rotates faster than the cam follower 30 and the second output cam members 40 and 50. A frictional force serving as a differential limiting force is generated between the second output cam members 50 that are faster than the cam follower 30 and the first output cam member 40. The frictional force is transmitted to the second output cam member 50 that rotates slower than the first output cam member 40 or the first output cam member 50 that rotates slower than the second output cam member 40. Relative rotation between the first and second output cam members 40 and 50 can be suppressed.

  The components of the differential limiting device 10 configured as described above are the same as the conventional ones except for the internal structure of the differential case 20. Therefore, the present invention is not limited to the illustrated example. The internal structure of the differential case 20 has the main features of the present invention. As a basic configuration of the differential case 20, for example, a gear extending in the rotation axis direction of the differential case 20 with a predetermined interval is formed on the inner peripheral surface of the bottomed cylindrical case body 21 by a generating method such as gear shaper processing or hobbing processing. Are provided with a plurality of concave and convex portions 28,.

  The differential case 20 is formed by forging or casting at least a bottomed cylindrical case body 21. In the present invention, although not particularly limited, the case main body 21 is preferably formed of a casting material. As the casting material, for example, a general casting material such as a spheroidal graphite cast iron material can be used. The casting material is an inexpensive material, and can reduce the number of processing steps and the material cost as compared with the case main body formed of the forging material.

  After the bottomed cylindrical case body 21 is formed by forging or casting, the bottomed cylindrical case body 21 extends in the direction of the rotational axis of the differential case 20 at a predetermined interval on the inner peripheral surface from the open end to the bottom of the bottomed cylindrical case body 21. A large number of concave and convex portions 28,..., 28 are formed in a gear shape by gear cutting which is machining. Annular machining relief portions are formed on both front and rear side portions in the longitudinal direction of the uneven portion 28 formed in a gear shape on the inner peripheral surface of the case body 21.

  After the bottomed cylindrical case body 21 is formed by forging or casting, a plurality of uneven portions 28 are machined into the inner peripheral surface from the open end to the bottom of the bottomed cylindrical case body 21 by machining. By creating a tooth mold with the desired tooth profile, tooth height, tooth width, number of teeth and number of teeth, it is possible to create uneven parts that do not require post-processing such as cutting and finishing, which is mechanical processing after molding such as forging or casting. Can be formed. This is a simple process that does not require a strict cutting and finishing process, and it is possible to achieve an improvement in forming processability and to reduce a manufacturing cost.

  Further, after the bottomed cylindrical case body 21 is formed by forging or casting, the inside of the bottomed cylindrical case body 21 is formed into a gear shape by gear cutting, so that the cam follower 30 and the gear shape are formed. It is no longer necessary to increase the precision of the cutting and finishing processing of the tooth contact with the concavo-convex portion 28, and the meshing accuracy and the alignment accuracy between the bottomed cylindrical case body 21 and the cam follower 30 can be achieved at the same time. it can. Therefore, the manufacturing process can be simplified, mass production processing is easy, and an inexpensive product with excellent quality can be obtained.

  In the first embodiment, the cam portions 41 and 51 of the output cam members 40 and 50 are formed in an annular shape. However, the present invention is not limited to the illustrated example. By forming the portions 41 and 51 in a disc shape, the output cam members 40 and 50 can be constituted by the rotating shaft portions 42 and 52 having blind holes. By adopting this configuration, when the first and second output cam members 40, 50 are assembled inside the differential case 20, the inner peripheral surface of the differential case 20 and the rotary shaft portions 42, 52 of the output cam members 40, 50 are assembled. A sealed space for enclosing the lubricating oil can be formed in the differential case 20 by a pair of seal members (not shown) interposed in a gap between the output cam members 40 and 50. Lubricating oil can be enclosed in the differential case 20 before connecting the shaft.

[Second Embodiment]
FIG. 4 is an enlarged view of a main part schematically showing a configuration example of the differential case 20 and the cam follower 30 according to the second embodiment of the present invention. FIG. 4 schematically shows a part of the differential case 20 and the cam follower 30 as in FIG. In the second embodiment, substantially the same members as those in the first embodiment are given the same member names and symbols.

  In FIG. 4, the concavo-convex portion 28 of the bottomed cylindrical case main body 21 in the differential case 20 has a tooth shape composed of a straight tooth tip surface and a semi-circular surface tip fillet. As another preferred example of the uneven portion 28 of the bottomed cylindrical case body 21, a general gear-shaped uneven portion, for example, a tooth shape can be formed by a geometric curve such as involute or cycloid. In the second embodiment, a bottomed cylindrical case body 21 is formed by forging or casting, and then a tooth shape is formed in a gear shape by gear cutting in the bottomed cylindrical case body 21. However, the present invention is not limited to this. For example, when molding the bottomed cylindrical case main body 21 by forging or casting, the inner peripheral surface of the bottomed cylindrical case main body 21 is formed. By forming the concavo-convex portion into a rough shape, a tooth shape can be created in a gear shape by gear cutting which is machining after the bottomed cylindrical case body 21 is formed.

[Third Embodiment]
FIG. 5 is an explanatory diagram schematically showing a configuration example of the differential case 20 and the cam follower 30 according to the third embodiment of the present invention. FIG. 5 shows a state where the spacer 63, the radial needle bearing 61, the thrust needle bearing 62, the second output cam member 50, and the case cover 22 are removed from the case body 21. In the third embodiment, substantially the same members as those in the above embodiments are given the same member names and symbols. Therefore, the detailed description regarding these members is omitted.

In the first embodiment, the configuration example in which the number of teeth (the number of tooth spaces) of the uneven portion 28 in the differential case 20 is set to the same number as the number of cam followers 30 has been described. This embodiment is different from the first embodiment in that the set number of the uneven portions 28 of the differential case 20 is set to an integral multiple of the set number of the cam follower 30. According to the example of illustration, the uneven | corrugated | grooved part 28 of the differential case 20 is set to 24 pieces. On the other hand, the number of cam followers 30 is set to twelve. As shown in FIG. 5, the semicircular arc-shaped sliding surface 34 of the cam follower 30 is in contact with the protruding surfaces of a pair of adjacent concavo-convex portions 28 in the differential case 20. The protrusion engaging portion 33 of the cam follower 30 is slidably engaged with the groove surface between the adjacent convex portions except for the groove surface formed on both sides of the pair of adjacent uneven portions 28. ing.

  In the third embodiment, the set number of the uneven portions 28 of the differential case 20 is set to twice the set number of the cam follower 30, but the present invention is not limited to this. In the third embodiment, the inner peripheral surface of the differential case 20 is toothed to create a tooth shape, for example, with respect to the number of concave and convex portions 28 of the differential case 20, the engaging portion 33 of the cam follower 30. Of course, the number can be set to an integer multiple of 3 or more. By creating the tooth shape of the inner peripheral surface of the differential case 20 in a gear shape, the degree of freedom in designing the gear-shaped uneven portion 28 in the differential case 20 is increased, and the number of teeth (the number of tooth grooves) and the tooth profile of the uneven portion 28 are set. Can be easily performed.

[Fourth Embodiment]
FIG. 6 is an explanatory view schematically showing a configuration example of the differential case 20 and the cam follower 30 according to the fourth embodiment of the present invention. FIG. 6 shows a state in which the spacer 63, the radial needle bearing 61, the thrust needle bearing 62, the second output cam member 50, and the case cover 22 are removed from the case main body 21 as in FIG. 5. In the fourth embodiment, members that are substantially the same as those in the above embodiments are assigned the same member names and symbols.

  In the fourth embodiment, as in the third embodiment, the number of uneven portions 28 of the differential case 20 is set to 36 and the cam follower 30 is set to 12, but the cam follower 30 30 differs from the above-described embodiments in that two engaging protrusions 33 are provided on a semicircular arc-shaped sliding surface 34 that abuts against the protruding surface of the uneven portion 28 of the differential case 20. . As shown in FIG. 6, the semicircular arc-shaped sliding surface 34 of the cam follower 30 is in contact with the protruding surfaces of the three uneven portions 28,. The protrusion engaging portions 33, 33 of the cam follower 30 are formed between the three adjacent convex portions except for the concave groove surfaces formed on both side portions of the three adjacent concave and convex portions 28,. The two concave groove surfaces are slidably engaged.

  In the fourth embodiment, two protrusion engaging portions 33 of the cam follower 30 are set. However, the present invention is not limited to the illustrated example. As the engagement protrusions 33 of the cam follower 30, for example, any number of three or more can be provided at a predetermined interval at a portion corresponding to the uneven portion 28 of the differential case 20. In addition, the number of engagement protrusions 33 of the cam followers 30 can be set to be the same for each cam follower 30, but the number of engagement protrusions 33 set is different for each cam follower 30. Of course, it may be.

  As is clear from the above description, in each of the above embodiments, the number of teeth (number of tooth spaces), tooth height (tooth space) size, tooth profile, and the like of the concavo-convex portion 28 in the bottomed cylindrical case body 21 are arbitrarily set. The cam follower 30 is formed of a proper number of protrusion engaging portions 33 with an appropriate number by creating a gear shape in a gear shape by gear cutting in the bottomed cylindrical case body 21. Yes. However, the present invention is not limited to this. For example, the engaging portion 33 of the cam follower 30 can be constituted by an appropriate number of engaging recesses. The purpose of can be fully achieved. Therefore, the present invention is not limited to the above embodiments, and various design changes can be made within the scope described in each claim.

1 is a cross-sectional view schematically showing a typical differential control device of the present invention (first embodiment). It is explanatory drawing which shows roughly the example of 1 structure of the differential case and cam follower of the differential control apparatus in this invention (1st Embodiment). It is a principal part enlarged view of FIG. 2 (1st Embodiment). It is a principal part enlarged view which shows schematically the example of 1 structure of the differential case and cam follower in this invention (2nd Embodiment). It is explanatory drawing which shows roughly the example of 1 structure of the differential case and cam follower in this invention (3rd Embodiment). It is explanatory drawing which shows schematically one structural example of the differential case and cam follower in this invention (4th Embodiment). It is a perspective view which shows the power transmission mechanism of the vehicle carrying the conventional differential limiting apparatus. It is a disassembled perspective view of the conventional differential limiting device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Differential control apparatus 20 Differential case 21 Case main body 21a End part opening part 21b Flange part 21c Mounting hole 22 Case cover 23 Cylindrical part 24, 26 Bearing cylindrical part 25, 27 Shaft penetration part 28 Uneven part 30 Cam follower 31, 32 Contact Surface 33 Engagement portion 34 Sliding surface 35 Engagement surface 40, 50 Output cam members 41, 51 Cam portions 42, 52 Rotating shaft portion 60 Belleville spring 61 Radial needle bearing 62 Thrust needle bearing 63 Spacer

Claims (2)

A differential case that rotates by inputting drive torque,
A plurality of cam followers that have an engaging portion that engages with the inner peripheral surface of the differential case, and that are slidably disposed in the rotational axis direction of the differential case;
First and second cam surfaces having cam surfaces formed by ridges and valleys having a predetermined pitch, the cam surfaces being opposed to each other inside the differential case with the plurality of cam followers interposed therebetween. Output cam member,
The first and second output cam members are differential limiting devices that output a differential limiting torque proportional to the driving torque from the differential case via the plurality of cam followers,
The differential case is composed of a bottomed cylindrical case main body having an end opening at one end, and a case cover covering the end opening of the case main body,
The inner peripheral surface of the case body, and gear cutting are subjected have a concavo-convex portion that is toothed type created in the gear shape after molding the case main body, on both sides of the longitudinal direction of the uneven portion is annular Each machining relief part is formed ,
The set number of the concave and convex portions is set to be twice or more the set number of the cam followers, and the engaging portion of the cam follower is set to a number of two or more with respect to the concave and convex portions. And the uneven portion are configured to mesh with each other . Differential limiting apparatus according to claim 1, wherein said case body is made of casting material.

Images