JPH0218853Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a shift operation mechanism for an automatic transmission.

[Conventional technology]

A select actuator performs a select operation to swing and engage one of the shift shafts of the gear transmission, and a shift actuator performs a shift operation to move the shift shaft in the axial direction, Automatic transmissions in which each actuator is controlled by an electronic control device according to driving conditions have already been proposed.

In this type of automatic transmission, if a select operation and a shift operation are performed at the same time when a select operation should be performed, or a shift operation and a select operation are performed at the same time when a shift should be performed, the smoothness of the operation is impaired and the shift axis This will cause the shift block and control lever to become locked and cause wear and tear on the shift block and control lever.

For this reason, conventionally, the select operation and the shift operation are performed based on signals from a position detection switch that detects the operating positions of the shift actuator and the select actuator. but,
This position detection switch has a high precision operating range.
Expensive items are required. Furthermore, in preparation for malfunctions due to failures such as wire breakage, safety must be ensured by providing a margin for operation time, which poses a problem in that the shift operation time becomes longer.

Incidentally, there is an interlock mechanism for the shift shafts of a transmission as disclosed in Japanese Patent Publication No. 57-23153, but when one of the shift shafts moves from the neutral position, the other It merely holds the shift shaft in a neutral position to prevent axial movement, and only when the select rod of the select actuator is held in one of the 3 to 4 select positions can the shift rod of the shift actuator be moved to the required position. The function is different from that which allows axial movement to a position.

[Problem that the invention attempts to solve]

An object of the present invention is to provide a shift operation mechanism for an automatic transmission that does not require a highly accurate position detection switch and allows the select operation and shift operation to function satisfactorily without adversely affecting each other.

[Means for solving the problem] In order to achieve the above object, the structure of the present invention is such that the shift rod of the actuator that rotatably supports the control lever and the select rod of the actuator that rotates the control lever are arranged in parallel. A pin having the same length as the pin hole is supported through the radial pin hole of the shift rod, and the pin selectively engages with a plurality of grooves corresponding to the select position of the select rod and the pin hole arranged coaxially with the pin. , and a pin that is engaged with the pin hole by a spring force are supported on the wall of the base frame.

[Effect]

The select rod and shift rod driven by each actuator are never actuated at the same time, and shifting of the shift rod is possible only when the select rod is held in one of a plurality of select positions. If the shift rod is not in the neutral position, the select rod cannot perform the select operation.

When the select rod 9 is in an arbitrary select position, the pin 29 is disengaged from the pin hole of the shift rod 15 and engaged by the force of the spring 37 in one of the grooves 31 to 33 corresponding to a plurality of select positions. When the select rod 9 is axially moved to another select position, the pin 29 engages the pin hole 35 of the shift rod 15, preventing simultaneous movement of the shift rod 15.

[Example of idea]

FIG. 1 is a side cross-sectional view of a shift operation mechanism of an automatic transmission according to the present invention. A select actuator and a shift actuator are arranged in parallel on the right end wall 1a of a base frame 1 (actually a Cordland box covering a gear box of a transmission). Only shift actuator 40 is shown in FIG. A shift rod 15 extending from the shift actuator 40 is slidably supported on the left end wall 1b of the base frame 1, and a boss portion 3 of the control lever 4 is attached to an intermediate portion of the shift rod 15.
is rotatably supported externally, and supported by a ring 14 so as not to be axially movable.

The control lever 4 is a shift block 20a, 20b, 20 of a known shift shaft 20 with a shift fork that engages a clutch sleeve of a synchronized mesh mechanism.
c (Fig. 3), and when the shift shaft 20 moves to the left or right in Fig. 1 as the shift rod 15 moves, the gears of a predetermined gear engage. I am starting to be able to achieve my goals. A spline 5 formed on the outer peripheral surface of the boss portion 3 is fitted into a cylindrical rotation transmitting member 6 so as to be relatively movable in the axial direction. The rotation transmission member 6 is engaged with a groove 21 formed in the base frame 1 and having an arcuate cross section.

Regarding the shift shafts 20, for example, in the case of a five-speed transmission, three shift shafts 20 are arranged parallel to each other as shown in FIG. 4, and each shift shaft 20 is provided with a shift rod 20a, 20b. ，
20c is coupled.

As shown in FIGS. 2 and 3, a rotation operating mechanism 12 that imparts rotational motion to the rotation transmission member 6 has an inclined groove 8 formed in the rotation transmission member 6 that is inclined with respect to the axis of the shift rod 15, and a select actuator. The slanted groove 8 is supported by the select rod 9 of the eater 41.
and a pin 10 that engages with the pin 10. A locking piece 11 provided on the select rod 9 is slidably engaged with a groove in the base frame 1.

The select actuator 41 with the select rod 9 has the same construction as the shift actuator 40 with the shift rod 15. 1st
As shown in the figure, the shift actuator 40 is provided with a small diameter cylinder 16 and a large diameter cylinder 19 on the right end wall 1a of the base frame 1, and a hollow large diameter cylinder 18 of the large diameter cylinder 19 is fitted into the large diameter cylinder 16. On the other hand, the large diameter portion 2a of the stepped piston 2 is fitted into the small diameter cylinder 16, and the small diameter portion 2b is fitted into the hollow portion of the large diameter piston 18. The boundary between the small diameter cylinder 16 and the large diameter cylinder 19 is opened to the outside through a passage 22.

By applying pressurized fluid to both or one of the large diameter cylinder 19 and the small diameter cylinder 16, the shift rod 15 is moved to the neutral position shown in FIG.
The large diameter piston 18 is pushed by the stepped piston 2 and moves to a position where it touches the end wall of the large diameter cylinder 19.

As shown in FIG. 5, according to the present invention, the base frame 1
A pin hole 36 through which the pin 27 is inserted is provided in the wall portion, and a bolt 26 is screwed into the screw hole concentric with the pin hole 36. A spring 37 is housed in a cylindrical portion provided in the bolt 26, and the spring 37 causes the pin 27 to move toward the shift rod 1.
It is possible to forcefully engage the pin hole 35 of No. 5. Also,
A pin hole 34 is provided in the wall of the base frame 1 coaxially with the pin hole 36, and a pin 29 is inserted into the pin hole 34.
A pin 28 having the same length as the outer diameter of the shift rod 15 is inserted into a pin hole 35 passing through the shift rod 15. A plurality of annular grooves 31 (three in the illustrated embodiment) in which the pin 29 engages with the circumferential surface of the select rod 9;
32 and 33 are provided. Pin 29 is in pin hole 34
be made longer than

Next, the operation of the speed change operation mechanism according to the present invention will be explained. First, when the control lever 4 is in the neutral position shown by the solid line in FIG. 4, the select actuator 41 and the shift actuator 40 are in the state shown in FIG. 5. At this time, the pins 27, 28, and 29 are aligned in a straight line, and the force of the spring 37 causes the pins 27, 28, and
A pin 29 is engaged via 28 in an annular groove 32 in the center of the select rod 9. At this time, the shift rod 15 can be operated to shift in the vertical direction in the figure, that is, to the 4th gear or the 3rd gear.

In FIG. 4, when rotating the end of the control lever 4 to the right and moving it downward to obtain the first gear, first move the select rod 9 of the select actuator 41 downward in FIG. (to the right in Figure 2), pins 29, 28,
27 is pushed away to the right against the force of the spring 37, and the large diameter piston 18 stops when it abuts against the end wall of the large diameter cylinder 19, and the pin 29 is inserted into the annular groove 3.
1. At this time, as shown in FIG. 6, the pin hole 35 of the shift rod 15 and the pin hole 3 of the base frame 1 are
The pin 28 straddles the shift actuator 40.
Even if the hydraulic circuit of the shift rod 1 malfunctions, the shift rod 1
5 does not work.

In FIG. 2, the select actuator 41
When select rod 9 moves to the right, pin 1
0 is rotated in the direction of the arrow, and the control lever 4 is rotated in the direction of the arrow.
is tilted around the shift rod 15, and the fourth
As shown by the broken line in the figure, it engages with the shift block 20a.

Next, when the shift rod 15 of the shift actuator 40 is moved to the right in FIG. 1, the control lever 4 that engages with the shift block 20a also moves to the right, and the shift shaft 20 is moved from the neutral position shown in FIG. It is pushed downward and meshing of the first gear gears is achieved. At this time, as shown in Figure 7, pin 2
9 is pulled in from the pin hole 35 of the shift rod 15,
The select rod 9 is engaged with the annular groove 31, and even if the hydraulic circuit of the select actuator 41 malfunctions, the select rod 9 will not operate.

Now, when the select rod 15 of the shift actuator 40 is moved upward in FIG.
The control lever 4 achieves meshing of the gears in the second gear.

In this way, the select actuator 41
By switching the fluid pressure circuit, the control lever 4 is rotated about the shift rod 15, and a select operation for selectively engaging one of the shift blocks 20a, 20b, 20c (Fig. 4) is achieved, and the shift By switching the fluid pressure circuit of the actuator 40, the shift blocks 20a, 20b, 2
The shift shaft 20 is actuated together with one of the gears 0c, and a shift operation is achieved in which the gears of a predetermined gear mesh.

[Effect of idea]

As described above, in the present invention, the shift rod of the actuator that rotatably supports the control lever and the select rod of the actuator that rotates the control lever are arranged in parallel, and a pin hole is formed in the radial pin hole of the shift rod. A pin that penetrates and supports a pin of the same length and selectively engages a plurality of grooves corresponding to the pin hole and the select position of the select rod that are aligned coaxially with the pin, and a pin that is engaged to the pin hole by a spring force. Since it is supported on the wall of the base frame, when one actuator is in operation, the other actuator is prevented from operating by engaging and disengaging three pins that cross the select rod and shift rod, which are parallel to each other.

Since the select rod of the actuator is held at a predetermined select position by engagement between the annular groove on the circumferential surface and the pin, a highly accurate position detection switch for detecting the select position of the select rod is not required.

Even if the shift actuator's hydraulic circuit is formed when the select rod is not at the required select position, malfunction of the shift rod is prevented, making it safe and enabling a circuit design that operates more quickly than conventional methods. .

[Brief explanation of drawings]

Fig. 1 is a left side sectional view of the shift operation mechanism of an automatic transmission according to the present invention, Fig. 2 is a left side view showing the main parts, Fig. 3 is a front sectional view taken along the line - in Fig. 1, FIG. 4 is a plan sectional view showing the arrangement of the shift block operated by the control lever, FIG. 5 is a plan sectional view of the same speed change operation mechanism, and FIGS. 6 and 7 are plan views explaining the operation of the same speed change operation mechanism. FIG. DESCRIPTION OF SYMBOLS 1... Base frame, 4... Control lever, 6... Rotation transmission member, 8... Inclined groove, 9... Select rod,
15...Shift rod, 12...Rotation operating mechanism,
27-29...pin, 31-33...annular groove, 3
4 to 36...pin hole, 37...spring, 40...select actuator, 41...shift actuator.

Claims (1)

[Scope of utility model registration request] A shift rod of an actuator that rotatably supports a control lever and a select rod of an actuator that rotates the control lever are arranged in parallel, and a pin of the same length as the pin hole is passed through and supported in a radial pin hole of the shift rod. , a pin that selectively engages with a plurality of grooves corresponding to the pin hole coaxially with the pin and a select position of a select rod, and a pin that is engaged with the pin hole by a spring force are supported on the wall of the base frame. A gear shift operation mechanism for an automatic transmission characterized by the following.