JPS58109740A - Stopping device for brake shoe clearance adjustment of drum brake - Google Patents

Abstract

PURPOSE:To stop the actuation of an adjusting device before the wear of a lining reaches its limit by a structure wherein a pair of screws, which are respectively screwed in a pair of non-pivoting member and have the same winding direction and yet the different pitches. CONSTITUTION:The outer periphery of a flange 21a, which is formed in the intermediate portion of an adjusting bolt 21 serving as a pivoting member, is notched with serrated adjusting teeth 21b. Furthermore, screw shafts 21c and 21d formed at both sides of the flagne 21a of the bolt 21 have the same winding direction of screw as each other, while the pitch of screw of the one screw shaft 21c is set larger than that of the other screw shaft 21d. In addition, both the screw shafts 21c and 21d are screwed in the non-pivoting tubular member 22 and 23 respectively. In case that the dimension L extending from the side surface 21a of the flange 21b of the adjusting bolt 21 to the end surface of the opening of the tubular member 23 is set to the value equivalent to the wear limit of the lining, further rotation of the adjusting bolt 21 becomes impossible when the abutment of the end surface of the tubular member 23 against the side surface 21a of the flange 21b or the attainment of wear limit of the lining is realized.

Description

[Detailed description of the invention] The present invention relates to the relationship between playing dotsum and play life V&-
A gap adjustment device K1gI which has a screw mechanism for itlllI11 is also O. In the case of a gap adjustment device that compensates for the increase in play life drum and OMal due to wear of the lining, if the adjustment device is of a type that can be extended uncontrollably, the driver can adjust the lining wear to a predetermined value. There is a risk of using it beyond the limit without realizing it. If the brake shoe continues to be used beyond the point of wear, the metal surface of the brake shoe will come into contact with the brake drum, and sand that has damaged the friction surface of the brake drum will no longer provide sufficient braking force, which is dangerous.

To this end, various proposals have been made in the past in which a stopping means is attached to the rotary member of the gap adjusting member, etc. to limit its extension. Fixed ones have drawbacks such as the need to replace the plastic lining even if there is a large amount of lining remaining.

The present invention solves the above-mentioned drawbacks with a simple structure, stops the operation of the KvI 4-sight scissors before the lining wear reaches the limit, and allows the driver to sense the increase in pedal stroke or hand lever stroke. This is to celebrate the equipment.

An example of this will be explained below with reference to the drawings. ＠/The figure shows the play position lightly held by the quay hold mechanism during drum play using a conventionally known manual gap adjustment type.
1. ja is a lining attached to the outside 11 of the play seat 3 during play, and 47 is a wheel cylinder and anchor member respectively arranged between the upper and lower adjacent ends of the play seat 30, both of which are fixed to the pack grate. has been done. 1 is a play 9 lever, one end of which is pivoted near the upper end of the play plate L-j, and the other end of which is connected to a control cable 9. An adjusting member 10 having the ability to adjust the gap between the middle part of the play lever ♂, the play shelving lever ♂ (not shown), and the lying = N3a is passed between the levers 9 and the play lever ♂. When the power is not activated, the return springs 1 and 1 pull the p-sheath 3 back in the direction of communication. Adjustment 11 member / funeral screw rod 13, adjustment nut>/
4 and a pipe member /j, one of which is engaged with the lever l, and the other threaded part of the threaded rod /3 is the pipe member /J.
' Adjustment nut that is loosely fitted into the screw head and screwed onto the screw head)
One end surface of /4t is in contact with the open end surface of tube member /j. The splitting groove of the other pipe member /j is engaged with the brake shoe notch groove -2b. Therefore, the outer diameter of the brake shoe λ3 is such that during play, the brake lever ♂ contacts the split groove bottom of the pipe member /j, the brake lever ♂ contacts the split groove bottom of the threaded rod /3, and the protrusion of the play 9 lever t. This is determined when part ♂a touches play*v:L-3.

In the above configuration, if the linings, 2a, and Ja are worn out and the force increases, use a tool such as a screwdriver from the back side of the back plate to adjust the adjustment by rotating the screwdriver by 4t'i. Then, attach the threaded part of the threaded rod /3 to the pipe member /! The length of the adjustment member/θ can be adjusted by extending the length of the adjusting member/θ, but since it can be adjusted without limit, there is a risk that the wear of the linings 2 and 3a will be exceeded. There is.

Fig. 2 shows an embodiment of the adjustment member J according to the present invention which eliminates the above-mentioned drawbacks, -/ is an adjustment bolt which is a rotating member, 7 langes are formed in the middle part thereof, and the outer circumference of 2/a is shown. #i
The threaded shafts 21t-% and 2/a on both sides have the same thread winding direction, but the thread pitch of one threaded shaft 210 is the same as that of the other threaded shaft 2. It is set larger than the thread pitch of /6. Then, the pipe members ↓ and U having internal threads that are screwed into the double threaded shafts 210.2/a4c are respectively fitted, and the pipe members 2 and 2 are respectively fitted.
The outer end of #3 is provided with nine brake shinnys, an auxiliary drive groove-a that engages with #2, and a splitter that engages with the pre-center lever t #1.2.
3& prevents the rotation of the play lever and the play lever/.

Therefore, when one screw shaft (J/□) is rotated by 1M in the direction in which it screws out from one tube member, the other screw shaft (C) is rotated by 1M in the direction in which it screws out from one tube member. CojfcQ is inserted, but due to the difference in the screw pitch between the two, the tuning 11 member and 20
Total length of 1. That is, the split groove 2ζ23& of the double pipe door material-2423
The length of the bottom barrier has not increased. Therefore, 1IB11〆le), 2
/'s 7 lunge/a If the dimension of the open end open type of the other tube member λ3 is set in advance to the wear angle of the lifting tool aSJa from the 4th surface, the - mouth end surface of the tube member - When the 7 twist, 2/a Ill il K comes into contact, the adjustment borsico l becomes unable to rotate, and the wear limit of the lining, 2&%3a, can be easily detected. In addition, #I to stop the rotation of the normal melt 2/ is as described above.
It is clear that the tip of the other screw shaft, 2/d, may be brought into contact with the diameter of the other tube member 3.

Next, an embodiment applied to a drum play machine with an automatic gap uniformity will be described with reference to FIGS. 3 and 9. Third
The figure is a plan view of a conventionally known drum brake, /θ
/ is a pack plate that is fixed to the non-rotation of the car body, /θλ
10j is grasshopper plate 10/upper near knee hold mechanism 70pe 10! PS during play that is lightly held with
-1102ts, /θja company playing shade /Qλ/
The lining attached to the outer periphery of θ3, 10/1 is a nine-wheel cylinder arranged adjacent to θ7, which is located between the 111 m north end of θ3 to the second 70 during play, and is a nine-wheel cylinder. It is fixed at 70/. /
/θ is an adjustment member that connects the adjacent ends of brake shoes /θ and /θ3, and also connects the brake drum (not shown).
It also has the function of closing the gap between θ3a and lining 702. /// is w441 member // Spring that holds θ in place, // ko is brake non-operating ats play shade / θ 2.103 It's a return yyy da.

The front adjustment member //θ is composed of a threaded rod //3, a l1ll111 nut //4, and a head //j, and is a rotating member (adjustment nut). Adjustment teeth are engraved. Threaded rod //3 and head //
The split groove provided on the outer end of j is Brayer Shinny/θ2.
103 to prevent rotation, and the threaded rod //
The screw shaft portion of the head //j is loosely fitted into the hole of the adjustment nut //￥. //F is a 1ll111 lever, the middle part of which is rotatably pivoted to A/θ3 during play, and one end of the A-key lever//B is substantially pivotably locked to the anchor bin/θ7. It is brought into contact with the rigid connecting member //7, and the other end is engaged with the adjustment g1m of //\. //l is an overload spring stretched between the adjustment lever //6 and the anchor bin 107;
At I, the adjustment lever //l is urged counterclockwise.

The operation of automatic gap adjustment in the above configuration will be explained.

Now, when the brake dome (not shown) is rotating in the direction of the arrow M, the brake is not activated and the L and brake shinny 10
3 is far away from the anchor pin y107, adjustment lever //6
Since the mopley pin A-703K is pivotally supported, they move almost as one in the direction away from the anchor pin //θ7. At this time, since the substantial connection length of the connection member //7 does not change, the adjustment lever //≦ rotates counterclockwise while in contact with the connection member //7. And the adjustment lever//
When the rotation amount of 6 is larger than the pitch of the adjustment teeth, tss
Rotate Hm to extend the adjustment member /10, so that during play the drum (not shown) and the lining /θ2 to /θ)
Adjust MM of a to a predetermined amount. Also, during the play A10
The frictional force of 3 is applied to the shape 7 during play via the adjustment member/10.
02, and when the thrust 4 of the Sukeki-betsu member //θ increases, the surface pressure on the screw part increases and the rounding torque that rotates the adjustment nut increases to an electric number. , in this case the overload spring //
Since I can expand and the connecting member //2 become a free part, it will not damage the automatic 1IIIs product. However, since the adjustment device with the above-mentioned configuration continues to make adjustments without limit, there is a risk that the wear limit of the lining 102m/(77aO) may be exceeded.

FIG. 9 shows an adjustment member/2 according to the present invention that eliminates the above-mentioned drawbacks.
This is an example of No. 7. /2/ is an adjustment nut which is a rotating member, and serrated adjustment teeth /=/b are carved on the outer periphery of its flange /2/a. Further, although the winding direction of the screw threads on both sides of the adjusting nut /2/ is the same, the internal milk a%'tr sibial direction is larger than that of the other. And the screw shaft @ which screws into this both internal screws /2/ to /2/d
1 bolt/2λ/23 having /-a and /3a are mounted respectively, and the outer end of the adjustment bolt /-/23 is set at a 90% height. Rotation is prevented by engaging with the middle cylinder/θ space/θ3, respectively. However, - glance bar//one tone 11 mel)/
When ll11m/, 2/b is rotated in the direction in which JJ is screwed out, the other key 11/23 is screwed in, but due to the difference in the thread pitch of both #A, the entire length of adjustment member /J, that is, both adjustment - The length of the 723 groove /22be/, 2jb bottom is extended to root /2. Therefore, the other adjustment bolt /, 23
If the dimension 2 from the bottom of the neck to the end face of the 14 nut/2/ is set in advance to the wear limit of 2 innings 702ζ/θ31, the adjustment nut saw/ when lining 702/θ3IL reaches the wear limit. Since the rotation of the shoe is stopped and the pedal stator is gradually increased thereafter, it is easy to know when to replace the shoe/θ shoe/θ3 during play.

As is clear from the above, according to the present invention, there is provided an adjustment and stop means that has a simple structure, is easy to assemble, and has a single operation. Further, even when the amount of wear of the linings is different from the set amount or when there is a large amount of lining remaining, the device can continue to be used by releasing the stop means, which has great effects. It should be noted that the present invention is not limited to the above-mentioned Soori example; for example, a fixed noodle material fixed to a back grate or the like may be screwed with a female thread to form one non-rotating member, and this may be utilized. It is also extremely easy to do so.

[Brief explanation of the drawing]

Figures 47 and 3 are front views of a conventionally known drum play, and Figures 11g and 3 are detailed views of the gap adjusting member according to the present invention. 6 3, /θ, 2%io3. ．． ．． ．． ．． V-LIPV knee, 10% ridge //θ, /20,00. , adjustment member, ko/,,,,adjustment pole F, which is a rotating member, --j,,
,,, pipe member which is a non-discreting member, /λ/,,,,,
The adjustment nut, which is a rotating member, is a non-zsuit material. Patent Applicant: Nisshinbo Co., Ltd. Kinshahaku Figure 4 Procedural Amendment (Voluntary) Date: 318, 1930, Japan Patent Office, Nagatomi, Indication of the Case: 1939, Patent Application No.-04λ-7, No. 3 Name of the Invention: Drum Brake Battle - Adjustment and stop device 3 Relationship with the case of the person making the amendment Patent applicant No. J@lσ, Nihonbashi Yokoyama-cho, Chuo-ku, Tokyo Amendment O subject v4 IIIA book - no details amtlL 嘱e Structure Contents of the amendment (1) Details Letter 4 purchase happy line WIKr non-lI@ ni," and Sani to ``non-a@ part," Tsurumasa stone.

Claims (1)

[Claims] During drum play of the type in which the adjustment member is adjusted by an adjustment member having a screw mechanism, the adjustment member is connected to a rotary member having adjustment teeth and a non-contact member screwed to both sides thereof. and a rotating member, the winding direction of the thread of the screw connection part O is isotropic and the thread pitch is made different, and the rotating member abuts one of the non-rotating members. 1. A gap adjustment and stop device during drum play, characterized in that the adjustment member is stopped from elongating when this occurs.