JPS62265035A - Differential limiting device changeover mechanism - Google Patents

Abstract

PURPOSE:To perform easily adjustment of the amount of piston motion in a differential changeover cylinder by installing an adjust bolt with stopper within a cylinder, and constructing it movable with an external adjusting part. CONSTITUTION:A piston 2 is actuated by applying a fluid pressure to a cylinder chamber 5, so as to be pressed to a stopper 14 of an adjust bolt 10 against the force of a resilient member 16. In this condition, the adjust bolt 10 is turned by an external adjusting part 12, and thus the piston 2 is moved to move a sleeve 4 in the axial direction through a fork 3 and a fork pin 17. Turning is stopped with a lock nut 39 when the tapered surface of said sleeve takes a specified position with respect to a moving element 29. This allows easy performance of adjusting the amount of piston movement from outside the cylinder, which minimizes slip movement to lead to accomplishment of the whole device in a small size.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Purpose of the Invention (a) Industrial Field of Application The present invention relates to a differential limiting device, that is, a differential device with limited differential for automobiles and other vehicles. This invention relates to a switching mechanism that performs restriction.

b In the conventional technology differential limiting device, switching between normal differential and differential limiting is as follows:
Generally, a piston of a fluid pressure cylinder moves a sleeve in a clutch case via a fork or the like, thereby switching the clutch.

For the above differential switching, positioning of the moving sleeve is important, and conventional means for positioning this sleeve include the following, for example. The piston of the single differential switching cylinder is positioned by hitting it against a step provided inside the cylinder or a cover on the side of the cylinder. Others do not use a cylinder for positioning, but have a stopper on a part of the sleeve, or have a claw clutch at the tip of the sleeve, which performs positioning when the tip comes into contact.

C Problems to be Solved by the Invention Among the switching mechanisms of differential limiting devices, the one in which the sleeve is positioned by applying a piston to a stepped portion or a side cover in the sill as described above has a problem in that the switching mechanism of the differential limiting device is It is not possible to adjust the lash or to respond to changes in the setting position due to the accumulation of processing tolerances for each part. In order to cope with this, it is necessary to provide a margin for the adjustment error of the positioning component in the action portion of the sleeve. The allowance is twice the adjustment error of each part, but if other parts are moved by the action part of the sleeve, twice the allowance is required between them, and a total of four times the allowance must be provided. Must be 1.

If there are more moving parts, twice as much allowance is required for each, so that the originally unnecessary allowance becomes twice, four times, eight times, etc. in total. The entire device, including the sleeve, becomes larger and has to be replaced, and a special design concept that allows for such a margin is required. Since the piston is stopped by hitting the stepped part of the cylinder or the side cover, it makes an impact sound and the threaded part may loosen due to the impact force. There are some models that adjust the amount of piston movement by inserting a shim or the like between the cylinder and the side cover, but this has problems such as the need to remove and install the cover each time the adjustment is made. be.

On the other hand, in models where positioning is performed on the sleeve side rather than the cylinder, the hydraulic tank is usually installed higher than the cylinder, so even if the hydraulic pressure in the cylinder is switched to drain pressure after the fork is moved, the oil pressure due to the difference in height is Residual pressure is applied to the cylinder due to column pressure and pipe resistance. Therefore, the fork pin constantly presses against the inner surface of the groove of the sleeve via the piston and fork. Moreover, the deflection of the fork, etc. that occurs during the movement of the fork tries to restore its original shape, and still acts as a force that constantly presses the fork pin against the inner surface of the groove of the sleeve. Therefore, there is a problem in that abrasion and heat generation occur between the fork pin and the inner surface of the groove of the sleeve, which speeds up repair and replacement.

The present invention aims to solve the above-mentioned problems of the conventional switching mechanism of a differential limiting device.

That is, the first objective is to make it possible to easily and quickly adjust the amount of piston movement from outside the cylinder, to minimize the amount of movement of the piston, fork, sleeve, and actuating parts due to sleeve movement, and to downsize the device. At the same time, the purpose is to eliminate the need for special design concepts that take into account various errors.

The second purpose is to attenuate the impact force when the piston hits the positioning part of the cylinder, eliminate impact noise, and prevent the threaded part from loosening due to the impact force.

A third object is to prevent the fork pin from coming into pressure contact with the inner surface of the groove of the sleeve due to residual pressure in the cylinder chamber or deflection during fork operation, and to improve the durability of the fork pin.

Arrangement of the Invention (a) Means for Solving the Problem The present invention provides a method for moving a sleeve (4) via a fork (3) with a piston (2) of an external differential switching cylinder (1), and normally In the switching mechanism of the differential limiting device that switches between differential and limited differential, the cylinder [1
) Adjustment bolts (9) (10) +9] 1o) that are screwed into the female threaded portions +7) (8) on the inner periphery are installed on both sides so as to form the side walls of the cylinder chambers (5) and (6), respectively. and each adjustment bolt (9) (10) (9) (1
0) is provided with an external adjustment part (llH12) for movement in the axial direction, and a stopper part Qa) (+
4) Install the piston (2) and adjustment bolt (9)
(10), an elastic material (+5+ (16)) for buffering and pushing back the piston (2) is provided on one side, and a fork pin (17) at the end of the fork (3).
However, the fork pin (
17) return it (18
).

In the above configuration, adjustment nuts (19) (81 are cylinder f+) with female threads (7+ +8) on the inner periphery on both sides of the cylinder f1
It is not limited to cylinders (1 cylinder).
) itself or the inner periphery of the side covers (to) (b) described later.

Adjustment bolts (9) (10) +9) (external adjustment part +II for moving 101 in the axial direction) (12) are for example the adjustment bolts (91 (to)
A protrusion (2110i!2) protruding outward K may be provided, and a hook portion for a rotating tool (path shown) may be formed on the protrusion (21)H.

The elastic material (+5) (16) may be a disc spring, for example, and may be provided on the side surface of the adjustment bolt (9) (10) (9+ +10) facing the piston as shown in the example shown, but is not limited thereto. Each aspect of (2) may also be used. It goes without saying that the buffering force received by the elastic member (+5) Qe+ before the piston (2) comes into contact with the stopper portion Qa) (14) should work below the maximum deflection of the elastic member (15) (+6). It is. Stopper part (+3) Q
4), for example, adjust bolts (9) (10) as shown in the figure.
) (The side surfaces of 91 (101) may be used to receive each side of the piston (2), but the invention is not limited to this. The piston (
1) may be stopped.

The return amount <1> of the fork pin (17), that is, the elastic material (1
The amount by which the fork pin (Iη) returns via the fork (3) due to the movement of the piston (2) due to the pushing back force of the sleeve (4) is determined by the deflection of the fork (3) when moving the sleeve (4) and the piston ( 2) to the fork pin θno, and the groove of the sleeve (4) (width (k)
The width is set to be slightly smaller than the difference (n) between the width of the fork pin 0η and the width (c) of the fork pin 0η. As a specific means for this setting, for example, in order to perform the above-mentioned buffering at a level below the maximum deflection of the elastic members (+5) (16), the side surface of the piston (2) or the adjusting bolt (91 (10)
) is formed with a concave hole (A) having an opening larger than that of the elastic member (15) Qej, and the above settings are made depending on the depth of the concave hole □□□. However, the setting is not limited to this, and such settings may be made using the elastic material (15) (taj), and the width (k) of the groove (18) of the sleeve (4) may be changed depending on the width (c) of the fork pin θ. Similar settings may be made.

A differential limiting device using this switching mechanism, as described above, uses the piston (2) of the external differential switching cylinder (+1) to slide the sleeve (4) through the fork (3). Any device that performs differential limiting switching will suffice, but one example will be explained using an illustrated example. Said sleeve (4) t
/i, Spring plate (
C) It is movable in the axial direction with the boss part in between. The kiln is a movable body, for example a steel ball, and a spring plate (
The through hole (which engages with (to) and whose height is greater than the depth of through hole ■.0]) of the boss part of the second uniform is a sleeve recess, and the sleeve ( When the sleeve (4) is pushed in, a part of the movable body (to) can be engaged with the sleeve (4).
) is formed on the side periphery.

(to) is the slope of the sleeve, and the sleeve (4) is normally used for differential.
The sleeve (4) is formed on the side circumference thereof so as to push the movable body (29) inside the through hole toward the outer clutch gooselet η when pulled out. The ring is pressed on the side, and in order to lock the spring plate (2 barrels) when the sleeve (4) is pulled out, the movable body (2 (g) is attached to the clutch case slope (described later).
It is formed on the side periphery of the sleeve (4) following the sleeve slope (A) so as to press against and lock the sleeve (4).

(to) is the clutch case recess, and the clutch case (2η
A portion of the movable body is formed to be engageable with the inner peripheral portion of the movable body. (b) When pulling out the sleeve (4) on the slope of the clutch case, move the spring plate (2) backward.
It is formed on the inner circumference of the clutch case (2η) so as to move the movable body pushed by the sleeve slope (A) in the anti-friction clutch direction.

In the figure, +231 (24) ld fluid inlet, (to) (b) is the side cover of the cylinder (I, but the adjustment bolt +91 (10) has a protrusion @1) (b). , it is pivotally supported by the central hole, and the male threaded part can be fixed with a lock nut. ■0])
is an elastic material attachment part which protrudes inwardly from the adjustment bolt (9) (lO), and holes (6) are formed on both sides of the piston (2) to which it can be engaged. ■ is a friction clutch.

b Function KI/' using the switching mechanism of the differential limiting device according to the present invention
i. First, make the following adjustments.

Fluid pressure is applied to the cylinder chamber (5) of one side of the cylinder (1) (left side in Figures 1 and 2) to move the piston (2) to the other side (right side in Figures 1 and 2). Push the side of the piston on the moving side against the pressing force of the elastic member (16) as shown in Fig.
). In this state, turn the adjustment bolt (10) using the external adjustment part θ2), and move the piston (2) in the axial direction (horizontal direction in the figure) by +101.
are moved together to move the sleeve (4) in the axial direction via the fork (3) and fork pin θ force. If the sleeve (4) is in the predetermined setting position, that is, the differential limiting device as shown in Fig. 2, the sleeve slope (a) of the sleeve (4)
For pressing and pressing, when the side surface (G) reaches the predetermined setting position with respect to the movable body I9), tighten the adjustment bolt (9) (10).
) +10+ Bring it to a complete stop and stop it with a lock nut. This allows accurate positioning without errors when the piston (2) is moved to the right for normal differential use and the sleeve (4) is pulled out via the fork (3) and fork pin (1). Ru.

Furthermore, fluid pressure is applied to the cylinder chamber (6) of the other cylinder (1) (right side in Figures 1 and 2), and the piston (2)
is moved to the left in the figure, and the stopper part (1) of the adjusting bolt (9) on the moving side is moved against the pressing force of the elastic member (15).
3) Press it. In this state, in the same manner as described above, move the adjustment bolt (9) on the movable side in the axial direction so that the sleeve (4) reaches the predetermined setting position, that is, the groove (18) of the sleeve (4) that engages the fork pin (17). ) is a friction clutch■
When the adjustment bolt (9) reaches a predetermined distance iIt corresponding to the wear of the adjustment bolt (9), the adjustment bolt (9) is stopped by the lock nut (c).

After the above adjustment, the differential limiting device with this switching mechanism is mounted on the vehicle, but its operating state is normally limited to one side (Fig. 1, Fluid pressure may be applied to the cylinder chamber (5) on the left side in Figure 2. As a result, the piston (2) moves toward the other side (toward the right in the figure) as shown in Fig. 1, but the side surface of the piston on the moving side reaches the stopper part (14) of the adjustment bolt (lO). As shown in Figure 3, it hits the elastic material (16) and is buffered. In the illustrated example, the concave hole (2) on the right side of the unswitched piston (2) is
The inner surface of the piston (2) hits the elastic material (16'l)
) attenuates the movement force of

After that, the piston (2) further moves in the same direction and moves
The side surface of the piston hits the stopper part (14)K of the adjustment bolt (lO) and stops. As mentioned above, at this stop position, the sleeve (4) moves via the fork pin 07) due to the movement of the piston (2).
This is a position where the device stops accurately at a predetermined setting position.

After that, the fluid pressure in the cylinder chamber (5) may be switched to the drain pressure. In this state, the pressing force of the elastic material (16) overcomes the residual pressure of the fluid and the sliding resistance of the piston (2), and the amount of deflection generated during the previous operation of the fork (3) and the piston (2) ) to the fork pin (17) by an amount slightly larger than the gap between the piston (2) and the fork pin (17). In this case, if the differential device is configured as shown in the illustration, the slope of the clutch case (
Since the movable body (29) in contact with the sleeve (4) is in pressure contact with the side wing, the sleeve (4) is locked and stopped. As the piston (2) is pushed back to the left, the fork pin (1) is also moved to the right by the corresponding return amount (1) as shown in Fig. 5 via the fork (3). .

This return amount (1) is determined by the groove (
18) and the width (c) of the fork pin θ'7). However, when pulling out the sleeve (4), the left side surface of the fork pin (17) and the groove (1) of the sleeve (4)
8) Although the left inner surface was in contact, this return amount (1) caused the fork pin (17) to move toward the sleeve (4) as shown in Figure 5.
) is maintained not in contact with any of the inner surfaces of the groove (18).

Next, when pushing in the sleeve (4) to limit the differential, it is sufficient to apply fluid pressure to the right cylinder chamber (6) in FIGS. 1 and 2, contrary to the above. As a result, the piston (2) moves to the left in the figure, but as before, it is first damped by the elastic material (15) on the moving side, and after damping, it comes into contact with the stopper part j+3)K of the adjustment bolt (9). will be stopped. This stop position is a position where the groove (18) of the sleeve (4) engages the fork pin (17) with a travel distance corresponding to wear of the friction clutch. In this case as well, when the fluid pressure in the cylinder chamber (6) is set to drain pressure, the piston (2) is pushed back to the right by the pushing force of the elastic member (15), and the fork pin θ is also moved to the left. be returned to the direction. This fork pin T171 vi Fj<,! :l
As above, the fork pin θ force and the sleeve (
4) Groove (18) is no longer in contact with both side surfaces.

C. Effects of the Invention a According to the present invention, the amount of piston movement of the differential switching cylinder can be easily adjusted from outside the cylinder, and the amount of movement of the sleeve is minimized to reduce the size of the entire device. be able to.

In other words, the conventional method of positioning the piston by applying it to the step inside the cylinder or the side cover requires adjustment of the tooth contact and backlash of each bevel gear, and changes in the set position due to the accumulation of machining tolerances. I can not cope. In addition, in order to accommodate this, it is necessary to provide a margin that is more than twice the adjustment error of each component in the sleeve's action part and each action part that is linked to the sleeve, which increases the size of the entire device and requires such a margin. A special design concept was required to anticipate this.

Furthermore, in the case where a shim or the like is interposed between the cylinder and the side cover to adjust the amount of piston movement, it is necessary to remove and attach the side cover each time the adjustment is made.

However, in the present invention, as described above, the adjustment bolt with a stopper part is installed inside the cylinder and is movable by the external adjustment part. The amount of piston movement can be easily adjusted from Therefore, the amount of movement of the sleeve is required to be the minimum necessary, making it possible to downsize the device, eliminating the need for special design concepts that allow for margins due to many adjustment errors, and facilitating design and manufacturing. It is something.

b. It can attenuate the impact force when the piston hits the positioning part of the cylinder, eliminate impact noise, and prevent the screw part from loosening. That is, in the conventional piston that is positioned by hitting it against the stepped part of the cylinder or the side cover, the impact at that time causes an impact sound and the threaded part loosens. In contrast, in the present invention, as described above, an elastic material for buffering and pushing back is interposed on the opposing sides of the piston and the adjustment bolt.

As a result, the impact force is attenuated, impact noise is eliminated, and the screw portion can be prevented from loosening.

The durability of the fork pin can be improved by minimizing the time during which the C fork pin contacts the inner surface of the groove of the sleeve. In other words, in the case where differential switching is performed by moving the sleeve through the actuation of the fork by the movement of the piston, even if the cylinder chamber is at drain pressure, the fork pin may be pushed out of the groove of the sleeve due to residual pressure or deflection when the fork is actuated. It is constantly pressed against the inner surface. As a result, the fork pins have to be repaired or replaced sooner due to wear and heat generation.

However, in the present invention, as described above, an elastic material is interposed between the piston and the adjustment bolt to buffer the piston and push it back, and the fork pin is adjusted by the sum of the width of the pin and the amount of return of the pin due to the return of the piston. It engages with a slightly wide groove in the sleeve.

Therefore, when the cylinder chamber is brought to drain pressure after the piston moves, the push-back force of the elastic material pushes the piston back by an amount that is slightly larger than the amount of deflection during the previous fork operation or the gap between the piston and the fork pin. . This return of the piston also returns the fork pin via the fork, but the amount of return is set smaller than the gap, which is the difference between the width of the groove and the width of the pin. Therefore, the fork pin does not come into contact with the inner surface of the groove of the sleeve, suppressing wear and heat generation of the pin, and greatly improving the durability of the pin.

[Brief explanation of drawings]

The figures show an embodiment of the present invention; FIG. 1 is a cross-sectional plan view of the main parts of the switching mechanism, FIG. 2 is a cross-sectional plan view of the differential limiting device of the switching mechanism, and FIG. 3 is a cross-sectional plan view of the switching mechanism. A partially enlarged cross-sectional plan view of the mechanism. Fig. 4 is an enlarged plan view showing the positional relationship between the sleeve groove and the fork pin when the sleeve is pulled out. Fig. 5 is a positional relationship between the sleeve groove and the fork pin after the fork pin is returned. FIG. Drawing code il+...Cylinder, (2)...Piston, (3)...Fork, (4)...Sleeve, (5
) (6)...Cylinder chamber, +7) (8)...Female threaded part, (91tto)...Adjustment bolt, C11
)α needle...external adjustment part, (13)(14)...stopper part, (15)(16)...elastic material, (+7)...
Fork pin, (18)...Groove, QC)...Groove width, (1)...Return amount, (C)...Pin width. (N ('')-s-〇のx-,>E Su^1 1. Indication of the case 1985 Patent Application No. 111710 2. Name of the invention Switching mechanism for differential limiting device 3. Person making the amendment Relationship to the case Patent applicant 1402-1 Representative director So Asano - Department 4, agent Address 590 address Teikyu Building 6, 3-4 Shinmachi, Sakai City, Osaka Prefecture Column for detailed explanation of the invention subject to amendment ■ On page 7, line 19 of the specification, "piston (1)" should be corrected to "piston (2)."

Claims (1)

[Claims] [1] Piston (2) of external differential switching cylinder (1)
), in the switching mechanism of the differential limiting device, in which the sleeve (4) is moved via the fork (3) to switch between normal differential and limited differential; Adjustment bolts (9) and (10) are installed inside the cylinder chambers (5) and (6) to form side walls of the cylinder chambers (5) and (6). (10) External adjustment part (11) for axial movement
(12) and each adjustment bolt (9)
The stopper portions (13) and (14) of the piston (2) are provided on the opposite side of the piston (10), and the stopper portions (13) and (14) of the piston (2) are provided on the opposite side of the piston (10). Elastic material (15) for buffering and pushing back the piston (2)
(16), and the fork pin (17) at the end of the fork (3) has a return amount (l) of the fork pin (17) due to the pushing back of the piston (2) and a width (l) of the fork pin (17). sleeve (4) with a width (k) slightly larger than the sum of m)
A switching mechanism for a differential limiting device, characterized in that the switching mechanism is configured to engage with a groove (18) of the differential limiting device.