JP3047617B2 - Rotation speed detection device for automatic transmission - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for detecting the number of rotations of a predetermined rotating member in order to monitor the progress of a shift in an automatic transmission of a vehicle.

[0002]

2. Description of the Related Art As is well known, in an automatic transmission for a vehicle,
Shifting is performed by changing the engagement / disengagement state of frictional engagement devices such as clutches and brakes, and the quality of the engagement / release timing at that time affects the output torque change, causing a shift shock. May worsen.
For this reason, recently, the progress of the shift is determined based on the number of rotations of a predetermined rotating member, and the hydraulic pressure in the friction engagement device is controlled based on the determination result, thereby preventing the deterioration of the shift shock.

[0003] For example, FIG. 3 shows an automatic transmission capable of four forward speed shifts including a three-speed transmission portion 1 for performing three forward speed shifts and an overdrive portion (O / D portion) 2. Hei 3-
In the invention of No. 55869, the number of rotations of the drum of the second clutch C2 is detected.

That is, 3 in the automatic transmission shown in FIG.
The speed change unit 1 includes a first planetary gear mechanism 3 and a second planetary gear mechanism 4, and each sun gear 5, 6 is provided with a sun gear shaft 7.
And the sun gear shaft 7 is
A first brake B1, which is a band brake, is provided on the outer periphery of the clutch drum of the second clutch C2, which is connected to the input shaft 8 via the clutch C2. A first clutch C1 is provided between the ring gear 9 of the first planetary gear mechanism 3 and the input shaft 8. Further, between the sun gear shaft 7 and the casing 10, the first
A one-way clutch F1 and a second brake B2 are arranged. The carrier 11 of the first planetary gear mechanism 3 and the ring gear 12 of the second planetary gear mechanism 4 are connected so as to rotate integrally, and between the carrier 13 of the second planetary gear mechanism 4 and the casing 10, A second one-way clutch F2 and a third brake B3 arranged in a parallel relationship with each other are provided.

The O / D unit 2 includes a set of planetary gear mechanisms 14, and a carrier 15 is connected to the carrier 11 of the first planetary gear mechanism 3 and the ring gear 12 of the second planetary gear mechanism 4. Are connected to a counter drive gear 17 which is an output member. A one-way clutch F0 and a clutch C0 are disposed between the sun gear 18 and the carrier 15 in parallel with each other, and a brake B0 is provided between the sun gear 18 and the casing 10.

As shown in FIG. 4, the drum of the second clutch C2, which is rotatably supported, and the sun gear drum 19, which is spline-engaged with the sun gear shaft 7, are engaged with respective claws. Then, the second clutch drum is integrally assembled and a plurality of square holes 21 are formed in the sun gear drum 19 at a predetermined pitch in the circumferential direction, and an electromagnetic pickup is provided to detect the square holes 21. ing. Therefore, when the second clutch drum rotates, the portion where the square holes 21 are formed and the portion where the square holes 21 are not formed alternately pass in front of the electromagnetic pickup, whereby the rotation speed is detected.

[0007]

[0006] Among the components of an automatic transmission, those that mainly transmit power are generally made of mild steel in terms of strength, workability, and price. An electromagnetic pickup can be used as the number detection device, and at the same time, the rotation speed of the outermost rotating body is detected. Therefore, in the above-described conventional device, the rotation speed of the clutch drum of the second clutch C2 is determined. It is to be detected. However, in this case, at the second speed, the second clutch drum stops, but the inner first clutch C1 drum continues to rotate. Therefore, the second clutch drum is provided with the square hole 21 of the sun gear drum 19 immediately below the electromagnetic pickup. When the clutch drum stops, the electromagnetic pickup erroneously detects the uneven portion of the first clutch C1 drum rotating below the second clutch drum via the square hole 21 by mistake for the detected portion.
There has been a problem that an accurate rotation speed cannot be detected, and as a result, a shift shock occurs due to detection failure.

The present invention has been made in view of the above circumstances, and has as its object to provide a rotation speed detecting device in an automatic transmission capable of detecting an accurate rotation speed.

[0009]

Rotational speed detection device in the automatic transmission of the present invention as a means for solving the above problems BRIEF SUMMARY OF THE INVENTION may, mutual pair of bottomed cylindrical body, an open end of their respective
Together are arranged on the same axis against the, the open end side of the bottomed cylindrical body hand, partially constant protrusion which has issued a predetermined amount collision on the outer circumferential side to expand the inner diameter to the circumferential pitch in made plural, axially open end of the other of the bottomed cylindrical body
A plurality of protruding claws are provided on the inner peripheral side of the protrusion in the axial direction.
Insert from the tip side and engage with the convex in the circumferential direction
By this, the pair of bottomed cylinders are assembled together
It is, and the electromagnetic picker <br/> quad-flop for outputting a signal by the magnetic field of the change, as a feature that you are disposed on the outer peripheral side of the front Symbol bottomed cylindrical body against toward the convex portion I have.

[0010]

[Action] is constructed as mentioned above in this inventions is,
A plurality of protrusions are formed at a constant pitch on the outer periphery of the open-ended side of one bottomed cylinder so as to increase its inner diameter, and the claw of the other bottomed cylinder is provided inside each protrusion. The pair of bottomed cylindrical bodies are
At least it can be assembled integrally in the rotation direction. Ma
And, one of the Kitotsu portion before formed into a bottomed cylindrical body, for detecting an electromagnetic pickup as a part to be detected, even without separately providing a square hole or the like as a portion to be detected, the rotation of the bottomed cylindrical body precisely Can be detected . That is, in the present invention,
The convex portion formed on one of the bottomed cylinders connects a pair of bottomed cylinders.
Function as an engagement part for
It functions as a part to be detected by the backup. Also, a pair of
Completely closed receiving part is formed by a bottomed cylinder
Therefore, even if another rotating body is arranged inside,
Of the rotating body is not detected by the electromagnetic pickup
Thus, erroneous detection of the rotation speed can be prevented.

[0011]

FIG. 1 is a partial sectional view of an automatic transmission according to an embodiment of the present invention. FIG. 2 is a sectional view of an automatic transmission according to an embodiment of the present invention. FIG. 4 is an exploded perspective view of the drum, and the automatic transmission shown here includes the gear train shown in FIG. 3 described above. That is, the input shaft 30 is connected to the turbine runner 32 of the torque converter 31.
, And is always driven to rotate. A clutch drum 33 of the first clutch C1 and a clutch hub 34 of the second clutch C2 are integrally attached to the tip of the input shaft 30. A number of friction plates 35 are spline-fitted to the inner peripheral portion of the clutch drum 33,
Outside the clutch drum 33, a second clutch C2
(Hereinafter referred to as a second clutch drum) 37 are arranged concentrically. As shown in FIG. 2, the second clutch drum 37 has a pair of bottomed cylindrical divisions 37a, 3a connected to each other with their ends abutting each other.
7b.

One of the divided portions 37a and 37b is rotatably fitted to a boss portion 40 protruding from an inner peripheral portion of the pump cover 39 so as to be rotatable.
The convex end 36 is formed in a pulse gear shape at a constant pitch in the circumferential direction by projecting a predetermined amount of the opening end side of the bottomed cylindrical shape to the outer peripheral side so as to partially enlarge the inner diameter. ing. Furthermore the open mouth end of the other split part 37 b
Are projected in the axial direction so that the engaging claws 38
6 are formed to have a predetermined width and length at the same pitch as the projections 36 so as to engage with the insides of the projections 6 respectively. The convex portion 36
The concave portion formed on the inner side of the electromagnetic pickup serves as an engagement portion for the engagement claw 38, and closely engages with the engagement claw 38 in the circumferential direction without any gap, and changes the magnetic field by rotating, thereby obtaining an electromagnetic pickup. Also serves as an object to be detected.

The two divided parts 37a and 37b are
After housing a predetermined rotating element such as a friction engagement device inside,
The engaging claws 38 of the other divided portion 37b are engaged with the inside of the convex portion 36 of the one divided portion 37a, and are integrally assembled. A plurality of friction plates 44 are spline-fitted at positions radially opposed to the clutch hub 34 of the second clutch C2 in one of the divided portions 37a, and the friction plates 44 are similarly splined to the clutch hub 34. Mated. Further, a brake band 45 of the first brake B1 is arranged on the outer peripheral side of the divided portion 37a.

An electromagnetic pickup 46 for outputting a signal according to a change in the magnetic field is provided on the casing 4 at a position corresponding to the convex portion 36 on the outer peripheral side of the second clutch drum 37 described above.
7 and is disposed.

In the above automatic transmission, if the torque converter 31 is operating, the clutch drum 33 of the first clutch C1 continues to rotate together with the input shaft 30 even if the rotation of the second clutch drum 37 stops. Since the outer peripheral side is covered by the second clutch drum 37, the drum 3
3 is not erroneously detected as the detected part. Therefore, the magnetic field changes as the second clutch drum 37 rotates and the convex portion 36 passes through the front end side of the electromagnetic pickup 46, and the electromagnetic pickup 46
7 is detected.

In the above embodiment, the automatic transmission having the gear train shown in FIG. 3 has been described as an example. However, the present invention is not limited to the above embodiment, and other gear trains may be used. The present invention can also be applied to an automatic transmission provided with

[0017]

As explained above, according to the present invention,
Since the convex portions formed at a constant pitch on the outer periphery of the outermost rotating body also serve as the engaging portion of the pair of bottomed cylindrical bodies and the detected portion of the electromagnetic pickup, square holes, pulse gears, etc. There is no need to separately provide a detection object, and erroneous detection is prevented, and accurate rotation can be detected. Therefore, smooth automatic gear shifting can be performed.

[Brief description of the drawings]

FIG. 1 is a partial sectional view showing an embodiment of the present invention.

FIG. 2 is an exploded perspective view of the clutch drum.

FIG. 3 is a skeleton diagram illustrating an example of a gear train of the automatic transmission.

FIG. 4 is a sectional view of a conventional clutch drum.

[Explanation of symbols]

 Reference Signs 30 Input shaft 33 First clutch drum 36 Convex part 37 Second clutch drum 37a Dividing part 37b Dividing part 38 Claw part 46 Electromagnetic pickup

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Michitaka 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (56) References JP-A-3-288018 (JP, A) JP-A-4-175545 (JP, A) JP-A-4-272563 (JP, A) JP-A-5-280622 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F16H 59/00-63 / 48

Claims (1)

(57) [Claims] 1. A pair of bottomed cylindrical body, an open end of their respective when placed on the same axis against each other bets
Moni, the opening end of the bottomed cylindrical body hand, partially convex portion was issued predetermined amount collision on the outer circumferential side to expand the inner diameter is made plural at a predetermined pitch in the circumferential direction, the other organic Multiple protruding axially at the open end of the bottom cylinder
Insert the claw part into the inner peripheral side of the convex part from the tip side in the axial direction.
To engage with the convex portion in the circumferential direction.
Assembled more the pair of bottomed cylindrical body integrally, and electromagnetic outputs a signal by the magnetic field changes Pickup
Flop, distribution on the outer peripheral side of the front Symbol bottomed cylindrical body against toward the convex portion
Rotational speed detection device in the automatic transmission, characterized in that you have been set.