JPH0130255Y2 - - Google Patents

Description

[Detailed Description of the Invention] a. Field of Industrial Application The present invention relates to a booster for operating a transmission mainly used in automobiles and the like.

b. Prior Art Generally speaking, a shift operation requires greater force than a selection operation when operating a transmission. For this reason, especially in buses and trucks that have large transmissions, boosters are attached to the transmissions, control rods, etc., so that smooth shifting operations can be performed with light force.

Although various types of boosters have been used in the past, the type shown in FIG. 1 is known as a relatively commonly used booster. This booster includes a pair of fixed valve seats 2 and 3 and a pair of floating valves 4 inside a piston rod 1.
By opening and closing the pair of idler valves 4 and 5 with an operating rod 6 serving as an input shaft, a boosted output is taken out from the striker 7.

That is, when the operating rod 6 is moved, for example, in the direction of arrow a in FIG. 1 using a change lever (not shown), the air pipe 8 is pulled by the operating rod 6 and moves in the same direction. A pressure ring 10 that is normally in contact with the valve lifter 9 is attached to the air pipe 8, so that the valve lifter 9 is pressed by the pressure ring 10 and moves forward in the left direction in FIG. As a result, the floating valve 5 is pressed by the valve lifter 9 and moves to the left in FIG.
A gap is created between the two. On the other hand, since compressed air is constantly supplied into the air pipe 8 from the direction of the arrow b in FIG. 14. In this way, pressure is applied to the piston 15, and this force is transferred to the piston rod 1.
The signal is transmitted from the signal to the striker 7, and further to a shift yoke (not shown) to perform a gear shift.

It should be noted that the structure of the output generating section constituted by the floating valves 4, 5, etc. is symmetrical in FIG. 1, so when moving the operating rod 6 in the direction of arrow c in FIG. 1, the same operation as described above is performed. will be done. However, in this case, the valve lifter 17 is pressed by the pressing ring 16 attached to the tip of the operating rod 6. In FIG. 1, reference numerals 18 and 19 are compression springs that always bias the valve lifters 9 and 17 in the backward movement direction, and 20 is a compression spring that always biases the pair of idle valves 4 and 5 in the closing direction.

By the way, in the booster as mentioned above,
For example, a detent mechanism as shown in FIG. 2 is employed. This detent mechanism normally holds the operating rod 6 at a predetermined neutral position with respect to the piston rod 1, while in operation it holds the operating rod 6 at a predetermined neutral position.
This is to allow relative displacement in the axial direction between the operating rod 6 and the piston rod 1, and to restrict relative rotation between the operating rod 6 and the piston rod 1. That is, this detent mechanism is mainly composed of a bolt 21 fixed to the operating rod 6, a steel ball 22, and a compression spring 23, as shown in FIGS. As shown in FIG. 2, it has an almost elliptical shape. Therefore, a gap 26 is formed between the inner circumferential surface of the through hole 25 of the piston rod 1 and the head 24 of the bolt 21, which allows relative displacement of the operating rod 6 and the piston rod 1 in the axial direction. Also,
Both side surfaces of the head 24 are configured to have the same curvature as the inner cylindrical surface of the through hole 25, and when the side surfaces come into contact with the inner peripheral surface of the through hole 25, the operation rod 6 and the piston rod 1 are connected. Relative rotation is restricted.

Further, a recess 27 is formed in the head 24 of the bolt 21, as shown in FIGS. 2 and 2, and a steel ball 22 urged by a compression spring 23 is normally pressed into this recess 27. Then, a predetermined input acts on the operating rod 6, and the operating rod 6
When the piston rod 1 and the piston rod 1 are displaced relative to each other in the axial direction, the steel ball 22 rides on the peripheral edge of the recess 27 against the compression spring 23. When the input to the operating rod 6 is released, the steel ball 22 clicks into the recess 27, and the relative positional relationship between the operating rod 6 and the piston rod 1 is returned to its original position (neutral position). It's starting to go back to normal. In this neutral state, the pair of valve lifters 9, 1
7 are completely moved back by a pair of compression springs 18 and 19, and the pair of idler valves 4 and 5 are completely closed by a compression spring 20.

c. Problems to be solved by the invention As above, an example of a conventional booster device for transmission operation and a detent mechanism adopted in this device has been schematically explained, but this type of device has the following problems. be. That is, (1) the steel ball 22 biased by the compression spring 23 constantly presses the head 24 of the bolt 21 in a direction perpendicular to the axial directions of the piston rod 1 and the operating rod 6; The urging force acts on the piston rod 1 via the steel ball 22, bolt 21 and operating rod 6. In other words, the operating rod 6 is compressed by the compression spring 23.
The piston rod 1 is constantly biased in the diametrical direction (in the upward direction in FIG. 2) by the biasing force of the piston rod 1, and is pressed against the inner circumferential surface of the piston rod 1. Therefore, the surface pressure on the sliding surfaces between the operating rod 6 and the piston rod 1 increases, and smooth movement of the operating rod is hindered.

(2) It is necessary to process the recess 27 in the head 24 of the bolt 21 and provide the steel ball 22, compression spring 23, etc., which complicates the structure and increases manufacturing costs.

The present invention was devised to effectively solve these problems, and its purpose is to improve the diametrical force acting on the operating rod by devising the structure of the detent mechanism. It is an object of the present invention to provide a booster for operating a transmission, which can eliminate power, reduce the number of parts, and simplify the structure.

d. Means for Solving the Problems In order to achieve the above-mentioned object, the present invention includes a pair of on-off valves inside a hollow piston rod,
a pair of valve operating members that reciprocate in the axial direction of the piston rod to open and close the pair of on-off valves, and an operating rod that moves in the axial direction of the piston rod to reciprocate the pair of valve operating members, respectively; In a booster for operating a transmission, the booster is configured to increase the input applied to the operating rod using fluid pressure and output it from the piston rod. a first pressing member that is attached to the valve operating member and presses one of the pair of valve operating members to move them forward; a second pressing member that moves the valve operating members forward; a pair of urging means that constantly urges the pair of valve operating members in the backward movement direction;
a pair of fixed stopper portions that restrict the return movement position of the pair of valve operating members in the axial direction of the piston rod, and when the on-off valve is not operated, the pair of valve operating members bias the pair of valve operating members. As the piston rod is moved away from each other along the axial direction by the biasing force of the means and is pressed against the pair of stopper portions, the pair of valve operating members abut against the pair of pressing members. In this way, the position of the operating rod relative to the piston rod can be regulated.

An embodiment of the present invention will be described below with reference to FIGS. 3 and 4. Note that in FIGS. 3 and 4, the same parts as in FIGS. 1 and 2 are given the same reference numerals.

FIG. 3 shows the structure of the output generating part of the booster for transmission operation according to the present invention. In the figure, 40 is a housing, and a cylinder 41 is attached to this housing 40. . A hollow piston rod 1 is inserted into the cylinder 41 so as to be slidable in the axial direction, and a piston 15 is fitted onto the outer periphery of the piston rod 1.

As shown in FIG. 3, a hollow operating rod 6 is inserted into the piston rod 1 so as to be slidable in the axial direction.
A pressing cylinder 16 is inserted and fixed. The base end 8a of the air pipe 8 is inserted into the press cylinder 16 and sealed. Therefore, when the operating rod 6 moves in the direction of arrow a in FIG.
The base end 8a of the air pipe 8 is pulled by the pressure cylinder 16 and moved in the same direction. In addition, 42 in FIG. 3 is an air filter.

As shown in FIG. 3, a presser plug 43 and a connector 44 are inserted and fixed into the tip of the piston rod 1, respectively. These presser plugs 4
3 and connector 44 each have a pipe insertion hole 4.
5 and 46 are provided, and the tip portion 8b of the air pipe 8 is slidably inserted into and supported by these insertion holes 45 and 46. and connector 4
Compressed air supplied from the outside to the injection hole 47 of No. 4 is introduced into the air pipe 8 from the tip opening 48. Note that the presser plug 43 and the connector 44 have an exhaust passage 49 that communicates with each other.
and 50 are provided, respectively.

A second pressing cylinder 10 is attached to the outer periphery of the tip 8b of the air pipe 8 and is linked to the operating rod 6 as described later. This second press ring 10 and the above-mentioned first press cylinder 16
a pair of fixed valve seats 2 on the left and right between the
3. Idle valves 4, 5 and valve lifters 9, 17 are provided. More specifically, the pair of fixed valve seats 2 and 3 are attached to the tip surface 43a of the presser plug 43.
and a ring-shaped step 51 formed on the inner peripheral surface of the piston rod 1. A pair of floating valves 4 and 5 are arranged inside the pair of fixed valve seats 2 and 3. These pair of floating valves 4 and 5 are each slidably inserted into the air pipe 8, and are normally pressed against the pair of fixed valve seats 2 and 3 by a compression spring 20. In addition, an O-ring 52 is provided on the inner periphery of the pair of floating valves 4 and 5, respectively.
are fitted to maintain an airtight state between the air pipe 8 and the air pipe 8.

Moreover, a pair of valve lifters 9 and 17 are arranged on the outside of the pair of fixed valve seats 2 and 3. These pair of valve lifters 9, 17 are connected to the air pipe 8.
They are slidably inserted into the respective parts, and are constantly biased in the backward movement direction by a pair of compression springs 18 and 19.
Note that O-rings 53 are fitted to the outer peripheries of the pair of valve lifters 9 and 17, respectively, to maintain an airtight state between them and the inner periphery of the piston rod 1 and the inner periphery of the holding plug 43. It's becoming like that. Furthermore, there is a gap 54 for exhaust between the inner peripheral surfaces of the pair of valve lifters 9 and 17 and the air pipe.
is formed.

A ring-shaped fixed stopper portion 55 is formed on the inner circumferential portion of the piston rod 1 on the outside of one valve lifter 17 (on the left side in FIG. 3). Similarly, a ring-shaped fixed stopper portion 56 is formed on the inner peripheral portion of the holding plug 43 on the outside (on the right side in FIG. 3) of the other valve lifter 9. And the pressed surfaces 5 of the pair of valve lifters 9 and 17
The peripheral edge portions 7 and 58 are normally pressed against the pair of fixed stopper portions 55 and 56. In this state, the pressing surfaces 59 and 60 of the pair of pressing rings 10 and 16 are connected to the pair of fixed stopper portions 55 and 56.
The pressure rings 10 and 16 are configured to be flush with each other, so that no gap is created between the pair of press rings 10 and 16 and the pressed surfaces 57 and 58 of the pair of valve lifters 9 and 17. Note that the pressed surface 57,
A groove 61 is formed in the radial direction in 58 so that compressed air can be easily exhausted, especially from between the pressed surface 57 and the pressing surface 59 of the pressing ring 10. In addition, in FIG. 3, 62 is a boot.

The structure of the output generating section of the booster for operating a transmission has been described above. Next, an example of a detent mechanism (stopper mechanism) employed in this device will be described with reference to FIGS. 4 and 4. That is, compared to the conventional detent mechanism shown in FIG. 2, this detent mechanism eliminates the steel ball 22, compression spring, etc., and also has no recess 27 in the head 24 of the bolt 21, making it extremely simple in structure. . Therefore, there is no force pressing the operating rod 6 against the inner circumferential surface of the piston rod 1, and the sliding resistance of the operating rod 6 is significantly reduced. The head 24 of the bolt 21 has an elliptical shape as in the past, which allows relative displacement in the axial direction between the piston rod 1 and the operating rod 6, and allows the idle valve 4 or 5 to be fully opened. is configured to be

The booster for operating the transmission is constructed as described above, and when the operating rod 6 is moved in the direction of arrow a or the direction of arrow c in FIG. In principle, the boosted output is taken out through the striker 7.
At this time, since there is no force pressing the operating rod 6 against the inner peripheral surface of the piston rod 1, the operating rod 6 moves extremely smoothly.

Next, when the input to the operation rod 6 is released,
The valve lifters 9 and 17 move back under the urging force of the compression springs 18 and 19, and the idle valves 4 and 5 are closed. At this time, the left and right valve lifters 9, 17 are pressed with their pressed surfaces 57, 58 against the fixed stopper parts 55, 56, respectively, and also come into contact with the press rings 10, 16, respectively, and are stopped, so that the operating rod 6
is always accurately returned to the neutral position as shown in FIG. When the valve lifters 9, 17 are in the backward movement state, all the biasing forces of the compression springs 18, 19 are received by the fixed stopper portions 55, 56, and no force is applied to the pressure rings 10, 16. Therefore, unless a force exceeding the setting force of the compression spring 18 or 19 acts on the operating rod 6, the operating rod 6
does not move, and the operating rod 6 will not move unexpectedly due to slight vibrations, shocks, etc. That is, when the operating force on the operating rod 6 is released (inactive), the neutral position of the operating rod relative to the piston rod 1 is accurately and automatically maintained by the biasing force of the compression springs 18 and 19 without any play. Retained. By appropriately setting the setting forces of the compression springs 18 and 19, it is possible to provide the change lever with a resistance feeling optimal for a shift operation.

Further, according to this example, the valve lifters 9 on the left and right,
17 fixed stopper portions 55 and 56 are provided, the biasing force of the right compression spring 18 acts only on the right valve lifter 9, and the biasing force of the left compression spring 19 acts only on the left valve lifter 17. The compression spring on the other side does not affect the valve lifter on the other side, and therefore, no problem occurs even if compression springs 18 and 19 with different setting forces are used. Furthermore, even if one of the compression springs, for example the right compression spring 18, is accidentally damaged for some reason, the compressed air in the cylinder chamber 14 will be introduced into the piston rod 1 through the through holes 13 and 12 in sequence. , the right valve lifter 9 is moved to the right by this compressed air, and the stopper part 5 is moved to the right.
6 and will not cause any problems.

Although one embodiment of the present invention has been described above, the present invention is not limited to the structure shown in the above embodiment and can be modified in various ways.

e Effects of the invention As described above, the invention forms a pair of fixed stopper parts (for example, fixed stopper parts 55, 56) on the inner circumference of the piston rod, and a pair of biasing means (for example, compression springs 18, 19). A pair of valve operating members (for example, a pair of valve lifters 9, 1
7) in a direction away from each other and press-fit them to a pair of fixed stopper parts to restrict their return position.
0 and 16), the biasing forces of the pair of biasing means for constantly biasing the pair of valve operating members in the backward movement direction are different from each other. Even when the valve operating member is in a fixed position, the backward movement position of the pair of valve operating members can always be controlled to be constant and accurate, and the operating rod can be accurately held at the neutral position without any play.

Further, according to the present invention, the urging force of the pair of urging means for urging the pair of valve operating members in the axial direction (sliding direction) of the operating rod is used to connect the valve operating member, the fixed stopper portion, and the pressing member. Since the operating rod can be held in the neutral position by the contact action between the piston rod and the piston rod, the outer circumferential surface of the operating rod is not pressed against the inner circumferential surface of the piston rod by the biasing force of a compression spring, etc., as in the conventional case. Therefore, the contact pressure on the sliding surfaces between them does not increase, and therefore, hysteresis loss during movement of the operating rod can be reduced, and the operating rod can be moved extremely smoothly.

Furthermore, since the compression spring, steel ball, etc. that press the operating rod against the piston rod can be eliminated, the structure of the detent mechanism is simplified and the cost of the booster can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view showing an example of a conventional booster for operating a transmission, FIG. 2 is a cross-sectional view of an operating force output section, and FIG. 2 is a longitudinal cross-sectional view perpendicular to the axis of the piston rod. 2 is a sectional view taken along the line -- in FIG. 1, FIG. 2 is a sectional view taken along the line AA in FIG. 2, and FIGS. 3 and 4 show an embodiment of the present invention, 3 is a longitudinal sectional view of the output generating portion of the booster for operating the transmission, FIG. 4 is a longitudinal sectional view of the detent mechanism, and FIG. 4 is a sectional view taken along the line B--B in FIG. 4. 1... Piston rod, 2, 3... Fixed valve seat,
4, 5...Idle valve, 6...Operation rod, 9,17
... Valve lifter, 10 ... Second pressing ring,
15... Piston, 16... First pressing ring,
18, 19... Compression spring, 20... Compression spring, 2
1...Bolt, 22...Steel ball, 23...
...Compression spring, 27...Recessed portion, 55, 56...Fixed stopper portion.

Claims (1)

[Claims for Utility Model Registration] Inside a hollow piston rod, a pair of on-off valves, a pair of valve operating members that reciprocate in the axial direction of the piston rod to open and close the pair of on-off valves, respectively; An operating rod that moves in the axial direction to reciprocate the pair of valve operating members, respectively, is provided, and an input applied to the operating rod is increased by fluid pressure and outputted from the piston rod. (a) a first pressing member that is integrally attached to the end of the operating rod and presses one of the pair of valve operating members to move them forward; , (b) arranged so as to be interlocked with the aforementioned operating rod;
a second pressing member that presses the other of the pair of valve operating members to move them forward; (c) a pair of urging means that constantly urges the pair of valve operating members in the backward movement direction; d) a pair of fixed stopper portions formed on the inner periphery of the piston rod to restrict the return movement position of the pair of valve operating members in the axial direction of the piston rod; As the pair of valve operating members are moved away from each other along the axial direction of the piston rod by the urging force of the pair of urging means and are pressed against the pair of stopper portions, A booster for operating a transmission, characterized in that the valve operating member is configured to abut against the pair of pressing members, thereby regulating the position of the operating rod relative to the piston rod.