JPH0825995A - Differential limiting device with lock mechanism - Google Patents

Abstract

PURPOSE:To provide a proper differential limiting condition via the complete engagement of a pilot clutch even under a small exciting force by providing a dog clutch excited sub-electromagnet capable of bypassing a pilot clutch for connecting differential rotating shaft members to each other for the direct connection thereof. CONSTITUTION:When a pilot clutch 11 is engaged via the excitation of a main electromagnet 9 and the rotor peripheral section 17 and a cam ring 12 in differential rotating state begin to rotate all together, a carrier 6 is pressed in an axial left direction, due to a thrust force generated between the section 17 and ring 12, and the carrier 6 via a ball 13. As a result, the whole of the carrier 6 moves left, thereby engaging a main clutch 14. In this case, clutch engagement state is maintained with the attraction force of the magnet 9 and, therefore, differential rotation is almost eliminated between the rotor 8 and the carrier 6. When a sub-electromagnet 15 is excited in this state, a dog clutch 16 bypasses the pilot clutch 11, and directly causes the section 17 and the carrier 6 to be engaged with each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnet type differential limiting device having a differential gear device and a differential limiting device having a differential lock mechanism.

[0002]

2. Description of the Related Art As an electromagnet type differential limiting device provided with a differential gear device of this type, there is, for example, a first conventional example shown in FIG. In this conventional example, a driving force from an engine (not shown) is transmitted to a ring gear that meshes with a drive pinion and a bevel tooth to rotate a differential case 31 that integrally fixes the ring gear. The differential case 3
The main clutch 44 and the pilot clutch 4 are arranged in the axial direction with a planetary gear constituting the differential gear unit sandwiched between the two.
1 is arranged. These clutches serve to limit the differential of the planetary gears. The driving force input from the differential case 31 is transmitted to an internal gear 32 of a planetary gear that constitutes a differential device as a part of the differential case 31, and further via a pinion gear 33, a carrier 36 and a sun gear 34. Distribution will be transmitted to. A plurality of the pinion gears 33 are axially supported on the circumference of the carrier 36 by a pinion shaft, and the internal gear 32 that meshes with the outside and the sun gear 34 that meshes with the inside mesh with the inside and outside of each of the pinion gears 33. are doing. The differential case 31 having the internal gear 32 further extends as an outer 37 to the outside of the pilot clutch 41.
Is configured to rotate integrally with the rotor 38 of FIG. The rotor 38 is externally fitted to the right output shaft 37 that is spline-fitted to the inner circumference of the carrier 36, and a right wheel drive shaft (not shown) is spline-fitted in the shaft portion of the right output shaft 37. The sun gear 34 constitutes the left output shaft 35,
Although not shown, a left wheel drive shaft is also spline-fitted in the shaft portion of the left output shaft 35. The pinion gear 33
The driving force transmitted from the differential case 31 is distributed to the carrier 36 of the right wheel system and the sun gear 34 of the left wheel system as the pinion gear 33 revolves in accordance with the driving resistance or the rotational speed difference between the left and right wheels. It is something that is transmitted.

When it is necessary to limit the differential action between the left and right wheels when a bad road such as a muddy road is encountered during traveling in such a differential drive state, the pilot clutch 4
The armature 40 is attracted by exciting the electromagnet 39 arranged outside the first rotor 38. By moving the armature 40 to the right in the axial direction by suction, the alternately arranged pilot clutches 41 between the armature 40 and the rotor 38 are engaged, and the outer 37 and the cam ring of the ball cam device in the differential rotation state. 42
When and are trying to rotate together, the thrust force generated through the ball 43 between the carrier 36 and the carrier 36 constituting the ball cam device pushes the carrier 36, which also functions as a pressure ring, axially leftward. Become. As a result, the entire carrier 36 pivotally supporting the pinion gear 33 moves to the left, and the main clutch 44 disposed between the planetary gear and the differential case 31 is moved.
Conclude As a result, there is no relative rotation difference between the carrier 36 and the sun gear 34, and the differential between the left and right wheels is in a limited state, so that the rotation of each pinion gear 33 is limited, and the internal gear 32, the pinion gear 33, and the carrier. 36 and the sun gear 34 also rotate with their relative rotation limited, and one of the drive systems idles due to the difference in the friction coefficient between the front and rear wheels and the tire. It removes the fate of and enables escape from bad roads.

However, in such an electromagnet type differential limiting device, although the exciting force of the electromagnet can be adjusted to adjust the thrust force generated in the pilot clutch, that is, the differential limiting force, the exciting force of the electromagnet is changed. Was limited, and it was difficult to obtain the complete engagement state of the pilot clutch. Then, the one described in JP-A-5-221246 as shown in FIG. 4 was devised. The structure of the second conventional example is basically the same as that of the first conventional example, but the permanent magnet 45 is adopted as the armature attracted by the electromagnet 39 in the pilot clutch 41. It is a thing. As a result, the exciting force of the electromagnet is selected by the current flowing through the electromagnet 39 in relation to the permanent magnet 45, and a predetermined differential limiting force is obtained. When a reverse current flows through the electromagnet 39, the magnetic force with the permanent magnet 45 is counteracted and the pilot clutch 41 becomes neutral, and the differential free state is established. When the supply amount of the reverse current is gradually decreased, the intermediate differential limited state is brought about by the engagement force of the pilot clutch 41 by the permanent magnet 45. Next, when a positive current flows through the electromagnet 39, the permanent magnet 45 and the electromagnet 39 attract each other, and the fastening force of the pilot clutch 41 increases. However, even in the second conventional example, since the pilot clutch is engaged by utilizing the magnetic force of the permanent magnet in addition to the exciting force of the electromagnet, there is a limit to these exciting forces. It was difficult to obtain the complete engagement state of the pilot clutch and the complete differential limited state, that is, the differential lock state. Further, when a permanent magnet is provided in the differential case 31, due to the adsorption of foreign matter such as abrasion powder in the lubricating oil,
There was a problem that the clearance setting of the pilot clutch changed and the differential limiting force became unstable.

[0005]

Therefore, according to the present invention,
By solving various problems in the electromagnet type differential limiting device including the conventional differential gear device, a reliable differential limiting state can be obtained by complete engagement of the pilot clutch even with a small exciting force by the electromagnet, and A differential limiting device with a lock mechanism that does not cause a shock when shifting to a complete differential limiting state.

[0006]

Therefore, in the present invention, as means for solving the above-mentioned conventional problems, the input from the differential case is distributed and transmitted to the left and right output shafts via the differential gear device. At the same time, in the electromagnet type differential limiting device for limiting the differential between the left and right output shafts by engaging the main clutch by the thrust force generated by the pilot clutch that engages between the differential rotating members by exciting the electromagnet, the pilot clutch In addition to the main electromagnet for engaging the clutch, a sub electromagnet for exciting the dog clutch that bypasses the pilot clutch and can directly engage the differential rotating members is provided. The dog clutch is spline-fitted to an armature attracted by a main electromagnet to operate the pilot clutch, and is attracted by the sub-electromagnet to engage with an outer peripheral portion of the rotor integrated with the differential case. Has been done. Further, the differential gear device may be a planetary gear type differential gear device, and the armature may be spline-fitted to a cam ring of a ball cam device that generates a thrust force when the pilot clutch is engaged. It may be spline-fitted to the carrier of the planetary gear constituting the ball cam device. Further, a coil spring is arranged between the dog clutch and the rotor.

[0007]

In the present invention, in addition to the main electromagnet 9 for engaging the pilot clutch 11, the pilot clutch 11
And the differential rotation member (the rotor outer peripheral portion 17
With the above-described configuration in which the sub electromagnet 15 for exciting the dog clutch 16 that can be engaged with the cam ring 12 or the carrier 6) is provided, excitation of the main electromagnet 9 causes the armature 1
When the rotor outer peripheral portion 17 and the cam ring 12 of the ball cam device, which are in the differential rotation state, try to rotate together with the carrier 6 that constitutes the ball cam device, The carrier 6 which also functions as a pressure ring is pressed axially leftward by the thrust force generated through the ball 13 during the time.
As a result, the entire carrier 6 supporting the pinion gear 3 moves to the left, and the planetary gear and the differential case 1 are moved.
The main clutch 14 arranged between and is engaged.
At this time, the armature 10 by the attraction of the main electromagnet 9 presses the pilot clutch 11 into the clutch engagement state, so that there is almost no differential rotation between the rotor 8 and the carrier 6 side. When the auxiliary electromagnet 15 is excited in this state, the dog clutch 16 bypasses the pilot clutch 11 and directly rotates the rotor outer peripheral portion 1 which is a differential rotation member.
7 and the cam ring 12 or the carrier 6 are fastened.
At that time, the dog clutch 16 is engaged with the rotor outer peripheral portion 17, but there is almost no differential rotation between the dog clutch 16 and the rotor outer peripheral portion 17 due to the engagement of the pilot clutch 11 by the main electromagnet 9. Therefore, the engagement is smoothly performed without shock or noise. As a result, even with a small excitation force by the sub electromagnet 15, a positive differential limiting state can be obtained by the complete engagement of the pilot clutch 11, and a differential with a lock mechanism that does not cause a shock when shifting to the complete differential limiting state. A restriction device will be provided. Also, after getting the full differential limited state,
When the sub electromagnet 15 is demagnetized, the coil spring 18 arranged between the dog clutch 16 and the rotor 8 causes
The differential limited state can be released promptly.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a first embodiment of a differential limiting device according to the present invention. Driving force from an engine (not shown) is transmitted to a ring gear that meshes with the drive pinion and bevel teeth, and is transmitted to a differential case 1 that integrally fixes the ring gear. A main clutch 14 and a pilot clutch 11 are axially arranged in the differential case 1 with a planetary gear constituting a differential gear device interposed therebetween. The driving force input from the differential case 1 is transmitted to the internal gear 2 on the inner circumference of the differential case 1, and further distributed and transmitted to the carrier 6 and the sun gear 4 via the pinion gear 3. The planetary gear is a double pinion type, which can smoothly give a left and right rotation difference. More specifically, a plurality of pinion gears 3 are rotatably supported on the circumference of the carrier 6 by a pinion shaft, and the inside and outside of each of the pinion gears 3 are externally meshed with the internal gear 2 and the sun gear is internally meshed. 4 mesh with each other. The differential case 1 having the internal gear 2 further extends to the outside of the pilot clutch 11 and is configured to rotate integrally with the rotor 8 of the pilot clutch 11.
The rotor 8 is externally fitted to the right output shaft 7 that is spline-fitted to the inner circumference of the carrier 6, and a right wheel drive shaft (not shown) is spline-fitted in the shaft portion of the right output shaft 7. The sun gear 4 constitutes a left output shaft 5, and a left wheel drive shaft (not shown) is also spline-fitted in the shaft portion of the left output shaft 5. The driving force from the differential case 1 transmitted to the pinion gear 3 is revolved around the pinion gear 3 according to the driving resistance or the rotational speed difference between the left and right wheels to rotate the carrier 6 of the right wheel system and the sun gear of the left wheel system. It is distributed to 4 and transmitted.

On the other hand, the armature 10 which is attracted by the excitation of the main electromagnet 9 and engages the pilot clutch 11
Are provided between the carrier 6 and the rotor 8 of the planetary gear. The pilot clutch 11 includes a multi-disc clutch group that is rotatable with the rotor 8 and is slidable in the axial direction, and a multi-disc clutch group that is rotatable and is slid with the cam ring 12 that constitutes the cam ball device.
At the time of fastening, thrust force is generated by the relative rotation between the cam ring 12 and the carrier 6 via the ball 13 which tries to rotate with the rotation of the differential case 1 and causes the carrier 6 to move in the axial direction, thereby causing the main clutch 14 to move. To conclude. In the present invention, in addition to the main electromagnet 9 for engaging the pilot clutch 11, the pilot clutch 11
A sub-electromagnet 1 that excites a dog clutch 16 that can be engaged between differential rotating members that are directly rotating relative to each other by bypassing
5 is provided outside the main electromagnet 9. In the present embodiment, the dog clutch 16 is spline-fitted to the armature 10 whose inner circumference is attracted by the main electromagnet 9 to operate the pilot clutch 11.
The armature 10 is configured to be attracted by the sub electromagnet 15 and engage with engaging teeth formed on an end surface of a rotor outer peripheral portion 17 integral with the differential case 1, and the armature 10 is thrust when the pilot clutch 11 is engaged. It is spline-fitted to the cam ring 12 of the ball cam device that generates force. Further, a coil spring is arranged between the dog clutch and the rotor. It should be noted that the rotor 8 has a two-layer stainless steel ring 19 which is a non-magnetic material.
Are embedded and are configured to separate the magnetic field during excitation by the main electromagnet 9 and the sub electromagnet 15.

Next, the operation of the present embodiment will be described. When traveling in a normal differential drive state, it is necessary to encounter a bad road such as a mud and limit the differential operation between the left and right wheels. When the main electromagnet 9 is excited, the armature 10 is attracted and the pilot clutch 11 is engaged, and the rotor outer peripheral portion 1
When 7 and cam ring 12 try to rotate together,
The thrust force generated between the carrier 6 and the carrier 6 via the ball 13 presses the carrier 6 axially leftward. As a result, the entire carrier 6 pivotally supporting the pinion gear 3 moves to the left in the drawing, and the main clutch 14 arranged between the planetary gear and the differential case 1 is engaged. At this time, the armature 10 by the attraction of the main electromagnet 9 presses the pilot clutch 11 into the clutch engagement state, so that there is almost no differential rotation between the rotor 8 and the carrier 6 side. In this state, when the sub electromagnet 15 is excited, the dog clutch 16 bypasses the pilot clutch 11 and directly rotates the rotor outer peripheral portion 17 which is a differential rotation member.
And the cam ring 12 via the armature 10 and the cam ring 12 strongly presses the carrier 6 in the axial direction via the balls 13, so that the main clutch 14 can be securely and completely diff-locked. it can. At that time, by engaging the pilot clutch 11 with the main electromagnet 9, the dog clutch 16 and the rotor outer peripheral portion 1
Since there is almost no differential rotation with 7, the engagement is smoothly performed without causing shock or noise. As a result, even with a small excitation force by the sub electromagnet 15, a positive differential limiting state can be obtained by the complete engagement of the pilot clutch 11, and a differential with a lock mechanism that does not cause a shock when shifting to the complete differential limiting state. A restriction device will be provided. In addition, after the complete differential limiting state is obtained, the sub electromagnet 15
When the magnetic field is demagnetized, the coil spring 18 arranged between the dog clutch 16 and the rotor 8 can quickly release the differential limited state.

Next, a second embodiment of the differential limiting device of the present invention will be described with reference to FIG. The structure of this embodiment is basically the same as that of the first embodiment, but in this embodiment,
The armature 10 is spline-fitted to the carrier 6 of the planetary gear that constitutes the ball cam device. As a result, the action of engaging the pilot clutch 11 of the armature 10 attracted by the excitation of the main electromagnet 9 is the same as in the first embodiment, but in the present embodiment,
When the sub electromagnet 15 is excited and the dog clutch 16 is attracted, not only the dog clutch 16 and the rotor outer peripheral portion 17, that is, the differential case 1 are integrated, but also the armature 10 and the carrier 6 that are spline-fitted to each other are integrated. Therefore, the relative rotation of the carrier 6 with respect to the differential case 1 is blocked, the pinion gear 3 does not rotate, and the sun gear 4 also rotates integrally, resulting in a complete differential lock state. Also in the present embodiment, as in the first embodiment, the engagement between the dog clutch 16 and the rotor outer peripheral portion 17 is smoothly performed without shock or noise, and the complete differential limiting is performed. When the sub electromagnet 15 is demagnetized after the state is obtained, the differential limited state can be quickly released by the coil spring 18 arranged between the dog clutch 16 and the rotor 8.

The embodiments of the present invention have been described above.
A differential gear device having an appropriate structure can be adopted within the scope of the present invention. Further, it goes without saying that the shape of the dog clutch, the manner of engagement with the rotor of the dog clutch, the configuration related to the cam ring of the armature or the carrier, the positional relationship between the main electromagnet and the sub electromagnet, and the like can be appropriately adopted.

[0013]

As described in detail above, in the present invention, in addition to the main electromagnet for engaging the pilot clutch, a dog clutch that can bypass the pilot clutch and directly engage between the differential rotating members is excited. Since the auxiliary electromagnet is provided, the armature is attracted by the excitation of the main electromagnet to fasten the pilot clutch, and when the rotor outer peripheral portion which was in the differential rotation state and the cam ring of the ball cam device try to rotate together, In addition to pressing the carrier, which also functions as a pressure ring, axially leftward by a thrust force generated through a ball between the carrier and the carrier 6 constituting the ball cam device, and engaging the main clutch, the auxiliary electromagnet By excitation, the dog clutch bypasses the pilot clutch and directly acts as a differential rotation member rotor. It is possible to conclude between periphery and the cam ring or the carrier, reliable differential limited state is obtained due to complete engagement of the pilot clutch even at a small excitation force due to the sub-electromagnets. Moreover, since the pilot clutch is engaged by the main electromagnet when the dog clutch engages with the rotor outer peripheral portion, there is almost no differential rotation between the dog clutch and the rotor outer peripheral portion.
The engagement is smoothly performed without shock or noise. Further, when the auxiliary electromagnet is demagnetized after the complete differential limited state is obtained, the differential limited state can be promptly released by the coil spring arranged between the dog clutch and the rotor.

[Brief description of drawings]

FIG. 1 is a diagram showing a first embodiment of a differential limiting device with a lock mechanism according to the present invention.

FIG. 2 is a diagram showing a second embodiment of the differential limiting device with a lock mechanism according to the present invention.

FIG. 3 is a diagram showing a first conventional example of a differential limiting device.

FIG. 4 is a diagram showing a second conventional example of a differential limiting device.

[Explanation of symbols]

 1 Differential Case 2 Internal Gear 3 Pinion Gear 4 Sun Gear 5 Left Output Shaft 6 Carrier 7 Right Output Shaft 8 Rotor 9 Main Electromagnet 10 Armature 11 Pilot Clutch 12 Cam Ring 13 Ball 14 Main Cutch 15 Sub Electromagnet 16 Dog Clutch 17 Rotor Outer Part 18 Coil Spring 19 Stainless ring

Claims (5)

[Claims] 1. An input from a differential case is distributed and transmitted to left and right output shafts via a differential gear device, and a main force is generated by a thrust force generated by a pilot clutch that engages between differential rotating members by excitation of an electromagnet. In an electromagnet type differential limiting device that engages a clutch to limit the differential between the left and right output shafts, in addition to the main electromagnet for engaging the pilot clutch, bypasses the pilot clutch to directly perform the differential rotation. A differential limiting device with a lock mechanism, comprising a sub electromagnet for exciting a dog clutch capable of engaging members. 2. The dog clutch is spline-fitted to an armature attracted by a main electromagnet for operating the pilot clutch, and is engaged with an outer peripheral portion of the rotor integral with the differential case by being attracted by the sub-electromagnet. The differential limiting device with a lock mechanism according to claim 1, wherein the differential limiting device has a lock mechanism. 3. The differential gear device is a differential gear device including a planetary gear, and the armature is spline-fitted to a cam ring of a ball cam device that generates a thrust force when the pilot clutch is engaged. The differential limiting device with a lock mechanism according to claim 2, wherein 4. The differential gear device is a differential gear device including a planetary gear, and the armature is provided on a carrier of the planetary gear that constitutes a ball cam device that generates a thrust force when the pilot clutch is engaged. The differential limiting device with a lock mechanism according to claim 2, wherein the differential limiting device has a spline fitting. 5. The differential limiting device with a lock mechanism according to claim 1, wherein a coil spring is arranged between the dog clutch and the rotor.