JPH0636341Y2 - Pin coupling device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to a pin connecting device suitable for use in pin connecting a working device provided in a construction machine such as a hydraulic excavator or a hydraulic crane.

[Conventional technology]

FIG. 3 and FIG. 4 show an example of a hydraulic excavator using a conventional pin coupling device.

In the figure, 1 is a lower traveling structure, 2 is an upper revolving structure provided on the lower traveling structure 1 so as to be rotatable, and the upper revolving structure 2 is provided with a driver's cab 3 located on the front right side. . Reference numeral 4 denotes a front portion which is provided on the front portion of the upper revolving structure 2 so as to be able to move up and down. The front portion 4 is roughly composed of a boom 5, an arm 6 and a bucket 7. These are a boom cylinder 8, an arm cylinder 9 and a bucket cylinder. It is designed to work with 10. The boom 5, the arm 6, the bucket 7, and the cylinders 8, 9, 10 are connected to the pin coupling devices 11, 11, ...
Are linked by.

Next, the pin coupling device 11 for coupling the arm 6 and the bucket 7 will be described as an example with reference to FIG.

In the figure, 12A and 12B are a pair of mounting brackets that are integrally provided on the bucket 7 as one member, and bushes 13 and 13 are press-fitted into the mounting brackets 12A and 12B. The side has a pin insertion hole 14. Reference numeral 15 denotes a boss portion that is integrally provided on the tip end side of the arm 6 and serves as a mating member. The boss portion 15 is disposed between the mounting brackets 12A and 12B, and the connecting pin 17 described later is attached to the mounting brackets 12A and 12B. Are rotatably connected by. Further, an annular groove 15A is formed at the center of the shaft on the inner peripheral side of the boss portion 15,
The groove 15A is filled with grease or the like. 16, 16 are press-fitted into the boss portion 15 from both sides in the axial direction, and
Is a pair of bushes arranged on both the left and right sides of the.

Reference numeral 17 denotes a connecting pin having a flange portion 17A provided on one side shaft end and a chamfered portion 17B formed on the other side shaft end, the connecting pin 17 penetrating the bushes 13, 16, 16, 13 at both ends. By inserting the side into the pin insertion hole 13 of each bush 13 of each mounting bracket 12A, 12B, the boss portion 15 is rotatably connected to the mounting bracket 12A, 12B. A screw hole 18 is formed in the end face of the connecting pin 17 on the chamfered portion 17B side, and a bolt 24 described later is screwed into the screw hole 18.

Reference numeral 19 denotes a stopper for preventing the connecting pin 17 from coming off. The stopper 19 is provided in one side surface of the stopper body 20 formed in a disk shape, and the chamfered portion 17B of the connecting pin 17 is provided. Fitting recess 21 having a tapered portion 21A into which
And a bolt accommodating portion 22 provided on the other side surface of the stopper main body 20 and accommodating a head portion 24A of a bolt 24, which will be described later, and the stopper accommodating portion 20 so that the bolt accommodating portion 22 and the fitting recess 21 communicate with each other. And a bolt insertion hole 23 through which the bolt 24 is inserted. 24 is a chamfer of the connecting pin 17
A bolt for fixing the stopper 19 to the end surface on the 17B side is shown, and the bolt 24 is provided with a stopper 19 through a washer 25 for preventing loosening.
Of the connecting pin 17 and the screw hole 18
Is screwed to. The head 24A of the bolt 24 is housed in the bolt housing 22 of the stopper 19 together with the washer 25.

As described above, the pin coupling device 11 according to the related art includes, for example, the mounting bracket 12 for the bucket 7 having the pin insertion hole 14.
A, 12B, a boss portion 15 provided on the tip side of the arm 6 as a counterpart member, and the boss portion 15 with the mounting brackets 12A, 12B.
A connecting pin 17 rotatably connected between B and the connecting pin 17
It is generally configured with a stopper 19 that is fixed to the through pin 24 by means of a bolt 24 and prevents the connecting pin 17 from coming off.When replacing the bucket 7, the bolt 24 and the stopper 19 are removed, and the connecting pin 17 is removed from the bushes 13 and 16 respectively. By pulling out, bucket 7
Are to be replaced.

When the boss portion 15 is connected between the mounting brackets 12A and 12B by the connecting pin 17, the collar portion 17A of the connecting pin 17 is connected.
Prevents the connecting pin 17 from coming off to the left in FIG. 4 by contacting the end face of the mounting bracket 12A, and the stopper 19 makes contact with the end face of the mounting bracket 12B, thereby connecting the connecting pin 17 to the right. It is designed to prevent it from being pulled out.

Further, the bolt 24 is provided in the bolt accommodating portion 22 of the stopper 19.
Since the head 24A of the bolt 24 is housed together with the washer 25, earth and sand do not directly hit the head 24A of the bolt 24 during excavation work, and the bolt 24 can be prevented from being damaged. Further, since the tapered portion 21A of the stopper 19 is brought into contact with and fitted to the chamfered portion 17B of the connecting pin 17, there is no gap between the connecting pin 17 and the stopper 19, so that earth and sand enter between them. In addition to being able to prevent
Even if earth, sand or the like hits and the impact is generated, the impact is transmitted to the connecting pin 17 via the tapered portion 21A and the chamfered portion 17B of each stopper 19, so that the impact is not directly transmitted to the bolt 24. Therefore, the durability of the bolt 24 can be improved, and by preventing the stopper 19 and the connecting pin 17 from falling off, the bucket 7 can be prevented from falling off.
It is possible to improve safety.

[Problems to be solved by the device]

However, in the above-described conventional technique, the diameter of the bolt accommodating portion 22 of the stopper 19 is only slightly larger than the diameter of the head 24A of the bolt 24, and the head 24A of the bolt 24 and the bolt accommodating portion are accommodated. Since an annular deep groove is formed between the portion 22 and the portion 22, when excavating earth and sand, etc., the earth and sand are clogged between the head 24A of the bolt 24 in the bolt accommodating portion 22, and when exchanging the bucket 7, etc. There is a problem that the bolt 24 cannot be removed unless the clogged soil is removed, and it takes a lot of time to remove the sediment.

The present invention has been made in view of the above problems of the prior art. The present invention greatly simplifies the work of removing dirt and the like, and makes it possible to easily replace attachments such as buckets. Is intended to provide.

[Means for Solving the Problems]

In order to solve the above-mentioned problems, the features of the configuration adopted by the present invention are that the stopper is a disk-shaped stopper body, and the shafts of the connecting pins that are provided at both ends of the stopper body and have different outer diameter dimensions. A first and a second fitting recess formed with different diameters so as to be fitted to the respective ends, and a bolt which is bored in the stopper body so as to communicate between the fitting recesses and through which a bolt is inserted. It is composed of an insertion hole.

[Action]

With the above configuration, if the shaft end of the connecting pin is fitted in one of the first and second fitting recesses and the head of the bolt is housed in the other fitting recess. It is possible to effectively prevent clogging of the fitting recess in which the head of the bolt is accommodated, and even if clogging of the fitting is possible, it can be easily removed.

[Embodiment] An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. In addition, in the present embodiment, the same components as those of the above-described conventional technique are designated by the same reference numerals and the description thereof will be omitted.

In the figure, 31 indicates a stopper used in the present embodiment. The stopper 31 is a disk-shaped stopper body 32 and a conical tapered portion 33A formed on one side surface of the stopper body 32.
And a second fitting recess 34 having a conical tapered portion 34A formed on the other side surface of the stopper body 32 with an outer diameter smaller than that of the first fitting recess. It is composed of a bolt 24 between these mating recesses 33 and 34.
A bolt insertion hole (35) through which is inserted through the stopper body (32). Then, the taper portion 33A of the first fitting recess 33 is fitted (contacted) with the chamfered portion 17B formed at the shaft end of the connecting pin 17, and is fitted into the second fitting recess 34.
24 heads 24A are to be accommodated with a large gap.

Next, FIG. 2 shows an example in which the stopper 31 is used for a pin coupling portion having a diameter different from that of FIG.

In the figure, 41A, 41B are a pair of mounting brackets as one member, bushes 42, 42 are press-fitted into the mounting brackets 41A, 41B, the inner peripheral side of each bush 42 is a pin insertion hole 43. ing. 44 is an annular groove 44A in the axial center on the inner peripheral side
Bosses 45 and 45, which are formed as mating members, are a pair of bushes that are press-fitted into the boss 44 from both sides in the axial direction and whose inner end surfaces reach the respective side surfaces of the groove 44A. Four
Reference numeral 6 denotes a connecting pin that rotatably connects the boss portion 44 between the mounting brackets 41A and 41B. The connecting pin 46 is the connecting pin 17 described above.
Although it has a flange 46A, a chamfered portion 46B and a screw hole 47, the connecting pin 46 has a smaller diameter than the connecting pin 17, and the chamfered portion 46B fits into the fitting recess 34 of the stopper 31. And then fitted. Then, the connecting pin 46 fits the chamfered portion 46B into the second fitting recess 34 of the stopper 31, and the head of the bolt 24 is inserted into the first fitting recess 33.
The bolt 24 is inserted into the bolt insertion hole 35 of the stopper 31 via the washer 25 so as to accommodate the 24A, and is screwed into the screw hole 47 so that the stopper 31 can be prevented from coming off.

The pin coupling device according to the present embodiment has the above-mentioned configuration, and its operation is not different from that of the conventional technique.

However, in this embodiment, the connecting pin 1 is provided on both sides of the stopper 31.
Tapered part 33 that fits and fits chamfered part 17B, 46B of 7,46
A fitting recess 33, 34 having A, 34A is provided, and the fitting recess 33, 34 is provided.
Among them, for example, the fitting recess 33 is provided with the chamfered portion 17B of the connecting pin 17.
When mating with the
Since the head portion 24A is accommodated, a relatively large gap can be formed between the head portion 24A and the fitting concave portion 34, and it is possible to effectively prevent clogging of earth and sand during excavation work. You can
The work at the time of exchanging attachments such as the bucket 7 can be simplified. Further, the fitting recess 34 is formed in the chamfered portion 46B of the connecting pin 46.
Even when fitting the
The same action and effect can be obtained by receiving the external force acting on the stopper 31 with the connecting pins 17 and 46,
The durability of the bolt 24 can be improved.

Furthermore, since a single stopper 31 can be used for the two types of connecting pins 17 and 46, the parts can be made common and the cost can be reduced. Further, since the stopper 31 has conical tapered portions 33A and 34A in the fitting recesses 33 and 34, it has been possible to manufacture it by casting or the like, while it was machined from a conventional round bar. Taper 33A,
With 34A, a draft taper can be given, and the work in production can be greatly shortened.

In addition, in the above-mentioned embodiment, the pin coupling device 11 used between the arm 6 and the bucket 7 has been described as an example, but the present invention is not limited to this, and for example, the pin coupling device between the arm 6 and the boom 5. It can also be adapted to other pin coupling devices 11, such as device 11.

[Effects of the Invention] As described in detail above, according to the present invention, since the first and second fitting recesses having different outer diameter dimensions are formed in the stopper, one of the fitting recesses is the connecting pin. Fit the shaft end of
By using the other as the bolt accommodating portion, it is possible to prevent shearing due to a large force acting on the bolt during excavation work, and a large gap can be formed between the head of the bolt and the fitting recess, It is possible to effectively prevent clogging of soil and the like, and facilitate the work of exchanging attachments such as buckets. Further, since it can be used as a common stopper for two types of connecting pins having different diameters, it is possible to reduce the number of parts and common parts, and it is possible to reduce the cost.

[Brief description of drawings]

1 and 2 show an embodiment of the present invention. FIG. 1 is a longitudinal sectional view of a pin coupling device, and FIG. 2 is another pin coupling device using the stopper shown in FIG. 1 as a common part. Fig. 3 and Fig. 4 show the prior art, Fig. 3 is an external view of a hydraulic excavator to which a pin connecting device is applied, and Fig. 4 is the direction of arrow IV-IV in Fig. 3. It is an expanded sectional view. 12A, 12B, 41A, 41B …… Mounting bracket (one member), 1
4,43 …… Pin insertion hole, 15,44 …… Boss part (counterpart member), 17,46 …… Connecting pin, 17B, 46B …… Chamfered part, 24…
… Bolts, 31 …… Stoppers, 32 …… Stopper bodies, 33,3
4 …… Mating recess, 33A, 34A …… Tapered part, 35 …… Bolt insertion hole.

Claims (1)

[Scope of utility model registration request] 1. A connecting pin that rotatably connects a boss portion of a mating member to one member having a pin insertion hole, and a shaft end of the connecting pin is detachably fixed by a bolt and the connecting pin is removed. In a pin coupling device including a stopper for stopping the stopper, the stopper is provided at both ends of the disk-shaped stopper body, and is fitted to shaft ends of connecting pins having different outer diameters. Therefore, it comprises first and second fitting recesses formed with different diameters, and a bolt insertion hole formed in the stopper body so as to communicate between the fitting recesses and through which the bolt is inserted. A pin coupling device characterized in that