JPH049254Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) This invention is an automatic clearance adjuster that automatically adjusts the clearance between brake shoes and wheels of a railway vehicle brake system. This invention relates to a detection stroke adjustment device for an automatic clearance adjuster, which sets the amount of play between the detection stroke necessary for the adjustment operation of the clearance adjuster and adjusts the detection stroke relative to the brake stroke. .

(Prior Art) As shown in FIG. 5, a brake device 1 for a railway vehicle applies brakes by pressing brake shoes 3 against wheels 2. To do this, the piston rod 5 of the brake cylinder 4 protrudes from the brake cylinder 4, and the horizontal lever 32 is rotated counterclockwise in the figure around its fulcrum 32a, and this movement is controlled by the piston rod 5 of the brake cylinder 4.
3 to the brake lever 6, and by pulling the brake lever 6 as shown by the broken line in the figure, the brake shoe 3 is pressed toward the wheel 2. At this time, the brake shoe 8 is pressed against the other wheel 7 by the brake lever 9, but the brake levers 6, 9 are connected to the brake push rod 10, and the brake shoe 8 is pressed against the other wheel 7. , 8 can provide a similar braking force. This braking force naturally requires greater force when the weight of the vehicle or the load loaded is heavy than when the vehicle is light. This difference in force can be calculated by using a horizontal lever, without changing the type (size) of the brake cylinder, as described later.
This can be handled by changing the leverage ratio of 2.

Therefore, the brake shoes 3, 8 wear out during operation. Along with this, the brake cylinder piston rod 5
As the stroke lengthens and the brakes become difficult to apply, adjust the length of the brake push rod 10.
As the brake shoes 3 and 8 wear, the brake push rod 10
The length of the brake link must be made longer (or shorter depending on the structure of the brake link). Since it would take a lot of effort to manually perform this adjustment work, automatic clearance adjustment is required to automatically adjust the length of the brake push rod 10 as the brake shoes 3 and 8 wear out. (Tokuko Showa 53-)
(See No. 42169, Utility Model No. 49-29851).

Such automatic clearance adjusters are widely used in various vehicles, but the piston stroke of the brake cylinder is varied depending on the size and weight of the vehicle in order to be advantageous in terms of maintenance and cost. It is standardized so that one model can be used on all vehicles without preparing different types, so there is only one type, and the shape of the bogie used is also standardized. However, different brake forces are required depending on the type of vehicle, so
The dimensional ratio of the horizontal lever 32, that is, the position of the fulcrum 32a from both ends of the horizontal lever 32 is changed, and the brake magnification is changed to correspond. A specific method for dealing with this is to provide a plurality of holes to serve as the fulcrum 32a on the horizontal lever 32, slightly shifting each other, and select appropriate holes from the plurality of holes according to the type of vehicle. This can be done by inserting a pin and using this point as a fulcrum, or by preparing several types of horizontal levers 32 with different hole positions for the fulcrum 32a and selecting and using them as appropriate, depending on the type of vehicle. This will depend on whether you can obtain the appropriate leverage. In this way, brake cylinder 4, brake levers 6, 9
When other parts are standardized without being changed depending on the type of vehicle, only the lever ratio of the horizontal lever 32 is changed to correspond to changes in the stroke of the brake lever. However, since it is advantageous to have fewer types of automatic clearance adjusters in terms of maintenance and cost, standardized shapes are required for various brake lever ratios. The detection stroke of the clearance adjuster (the amount of extension when the automatic clearance adjuster expands in response to the amount of wear on the brake shoes. In other words, the detection stroke of the brake cylinder piston remains constant even if the brake shoes wear out. This refers to the amount of extension of the automatic clearance adjuster to maintain the clearance (the same applies hereinafter).There will be some discrepancy between the two. In other words, the detection pitch (minimum detectable dimension) of the detection stroke of the automatic clearance adjuster and the horizontal lever 3
It is possible that the minimum change dimensions of the two leverage ratios do not match. Therefore, in order to adjust this discrepancy, a long hole 17 as shown in Fig. 6 was provided to create a relief, and the discrepancy was absorbed within the range of this relief.

To explain this structure, the automatic clearance adjuster 11, which is attached in place of the brake push rod 10 which is pivoted to the brake lever 6 by a pin 6a, is connected to the brake lever suspension link 12 and the pin 12a. Therefore, the connecting plate 13, which is pivoted, moves relative to each other. At this time, the coarse pitch feed screw 14 connected to the connecting plate 13 moves in the axial direction with respect to the automatic clearance adjuster 11. As shown in FIG. 7, the automatic clearance adjuster drive gear 15 is screwed into the feed screw 14, but since the feed screw 14 has a rough pitch and does not stand on its own, the feed screw 14 does not move in the axial direction. When you move,
The gear 15 rotates at that position. This causes the automatic clearance adjuster 11 to operate, and the length of the automatic clearance adjuster 11 is adjusted in accordance with the wear of the brake shoes. However, in the case of a lever, the feed screw 14
is not directly fixed to the connecting plate 13, but is fixedly attached to the center of a U-shaped plate 16 provided inside the connecting plate 13, which has a frame shape and is divided into left and right plates. A long hole 17 is bored in the U-shaped plate side part 16a, and a pin 18 is planted in the connecting plate 13.
is fitted into the elongated hole 17. By this,
When the connecting plate 13 moves relative to the automatic clearance adjuster, the pin 18 first moves in the elongated hole 17,
After reaching the end 17a of the long hole 17, the pin 18 pushes the long hole end 17a, and the U-shaped plate 16 moves.
The feed screw 14 fixed to this is moved, and from then on it moves together with the connecting plate 13.

In other words, the moving distance of the U-shaped plate to rotate the drive gear 15 that operates the automatic clearance adjuster 11 is the distance between the connecting plate 13 and the automatic clearance adjuster 11 by a clearance corresponding to the length of the elongated hole 17. It becomes smaller than the movement, and the conflict between the two is adjusted. In addition, in order to change the amount of free movement, a screw 1 is provided so that the U-shaped plate 16 and the connecting plate 13 are always in contact with each other.
6b performs fine adjustment work to change the clearance.

(Problem to be solved by the invention) In this way, the movement of the connecting plate 13 is controlled by the pin 18.
The pressure is transmitted from the U-shaped plate 16 through the elongated hole 17 to the feed screw 14, but the U-shaped plate 16 and its elongated hole 17 are exposed to the outside of the automatic clearance adjuster 11. For this reason, there was a problem in that it often became stuck due to freezing or rust and became unable to move.

The present invention was made in order to obtain a detection stroke adjustment device for an automatic clearance adjuster that does not cause icing or rust and can easily change the amount of free movement.

(Means for Solving the Problems) The present invention, as a means for solving the above problems, engages a gear with a feed screw having a rough pitch, and rotates the gear by moving the feed screw in the axial direction. ,
In an automatic clearance adjuster that is operated by the rotation of the gear, a nut is screwed onto the coarse pitch feed screw, the gear is attached to the spline outer periphery provided on the outer peripheral surface of the nut, and the A pair of washers that fit around the outer periphery of the feed screw, at least one of which is a stepped washer in which the height of the step protruding toward the other side can be arbitrarily set, are fixed to the nut with a clearance. This is what I did.

(Function) With this configuration, the connecting plate for operating the automatic clearance adjuster is directly connected to the coarse pitch feed screw. When the connecting plate is moved relative to the automatic clearance adjuster, the feed screw moves in the axial direction, but since there is a play between the nut screwed onto the feed screw and the washer, the nut does not move. Natsu continues to move forward until it touches the washer.
The gear fitted with splines around its outer periphery does not rotate. When the nut contacts the washer, the nut rotates due to the movement of the feed screw, and the gear around the nut also rotates to adjust the clearance. In this way, the clearance between the nut and the washer has the same effect as the length of the long hole of the U-shaped body having the long hole attached to the feed screw.

(Example) An example of the present invention will be described below with reference to the drawings. Fig. 2 is a diagram corresponding to Fig. 5 of the prior art, and the wheels 2, 7, brake shoes 3, 8, brake cylinder 4, piston rod 5, and brake levers 6, 9 have the same functions as in Fig. 5. Therefore, the same members will be represented by the same symbols. An automatic clearance adjuster 21 is installed between the lower pins 6a and 9a of the brake levers 6 and 9, and a connecting plate 23 is pivotally attached to the lower pin 22a of the brake suspension link 22. The connecting plate 23 has an axis parallel to the axial direction of the automatic clearance adjuster 21, and is directly connected to a coarse pitch feed screw 24 that moves in the axial direction.

As shown in FIG. 1, the coarse pitch feed screw 24 rotates the automatic clearance adjuster drive gear 25 that engages with it due to its axial movement, but in this case, the feed screw 24 shown in FIG. Like screw 14,
A nut 26 is screwed onto the feed screw 24 without being directly screwed onto the automatic clearance adjuster driving gear. A spline 27 is provided on the outer peripheral surface of the nut 26, and a spline groove 28 that fits into the spline 27 is formed on the inner surface of the shaft of the automatic clearance adjuster drive gear 25.
A gear 25 is attached to the outer periphery of a nut 26. Furthermore, washers 29 and 30 that fit around the outer periphery of the feed screw 24 are fixed to the front and rear of the nut 26. Washer 2
The spacing between 9 and 30 is the width of the gear 25, and the nut 26
Since the width of the nut 26 is smaller than that, the nut 26 is the washer 2.
It is installed with a gap between 9 and 30. Note that one washer 29 is a flat plate, but the other washer 3
0 is a stepped washer 30 as shown in FIG. By changing the dimension A of the stepped portion 30a of the stepped washer, the clearance α between the nut 26 and the washer 30 can be changed, thereby making it possible to adjust the stroke.

The drive gear 25 is constantly meshed with the clutch rotation gear 31 of the automatic clearance adjuster 21, and when it rotates over a certain angle, the automatic clearance adjuster 21 extends and performs the clearance adjustment operation, which is the same as the automatic clearance adjustment described above. This is similar to the container 11 and the like.

Although not shown in FIG. 1, the feed screw 24 is directly connected to the connecting plate 23, so when the connecting plate 23 moves to the right in the figure, the feed screw 24 similarly moves to the right. However, the nut 26 screwed onto the feed screw 24,
There is a play space α between the stepped washer 30, and the nut 26 and the gear 25 are spline connected and are movable in the axial direction, so the feed screw 24
The nut 26 moves without rotation until the end surface of the nut 26 and the stepped seat surface 30 come into contact with each other and the state shown in FIG. 4 is reached. Connecting plate 2
3 further moves to the left and the feed screw 24 also moves to the left, the nut 26 screwed into the feed screw 24 rotates and therefore the drive gear 25 also rotates. This causes the adjustment clutch gear 31 to rotate and perform automatic clearance adjustment. In this way, an operation similar to that of the elongated hole 17 and pin 18 of the U-shaped body 16 in FIG. 6 is performed.

(Effects of the invention) By having the above-mentioned structure of the invention,
By selecting and installing the stepped washers appropriately according to the type of vehicle, the automatic clearance adjuster will have a clearance appropriate for the vehicle type, so the stroke of the brake lever and the automatic clearance adjuster can be adjusted accordingly. Even if there is a small difference between the detection stroke and the detection stroke required for the adjustment operation, the detection stroke corresponding to the brake stroke can be adjusted by setting the amount of play between the two. Moreover, it is possible to reliably create a free space using only the internal elements of the structure, without using elongated holes exposed to the outside.
It also has the advantage that the amount of free movement can be changed by simply replacing parts.

[Brief explanation of drawings]

Fig. 1 is a sectional view of the feed screw and drive gear of the automatic clearance adjuster of the present invention, Fig. 2 is a perspective view showing the assembly of the feed screw, drive gear and stepped washer shown in Fig. 1; The figure is a schematic diagram of the brake mechanism of the present invention.
Figure 4 is a sectional view when the feed screw has moved by the amount of free movement from the state shown in Figure 1, Figure 5 is a schematic diagram of a conventional brake mechanism, and Figure 6 is a conventional detection stroke adjustment device using a long hole. FIG. 7 is a sectional view of a conventional feed screw and drive gear. 1... Brake device, 21... Automatic clearance adjuster, 24... Rough pitch feed screw, 25... Drive gear, 26... Nut, 27, 28... Spline, 29, 30... Washer, 32... ...Horizontal lever.

Claims (1)

[Scope of utility model registration request] A gear is engaged with a feed screw having a rough pitch, and the gear is rotated by the axial movement of the feed screw, and a nut is screwed into the feed screw having a rough pitch in an automatic clearance adjuster that is operated by the rotation of the gear. and a gear is attached to the spline outer periphery provided on the outer periphery of the nut, and a pair of washers that fit on the outer periphery of the feed screw are installed before and after the nut,
A detection stroke adjusting device for an automatic clearance adjuster, characterized in that at least one of the stepped washers is a stepped washer whose height can be arbitrarily selected, and the stepped washer is fixed to the nut with a clearance. .