JPH0575944U - Link mechanism - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a link mechanism that is easy to assemble, does not drop the pin, and does not project the head of the pin. [Structure] The through hole of the first link 1 is used as a dent hole 4, and the second link 2 is pivotally attached by a pin 6. Both ends 6a of the pin 6 have the same diameter as the through hole 5 of the second link 2, and the central portion 6b has the same diameter as the small diameter portion 4b of the sullar hole 4. If a force is applied to the second link 2 after the pin 6 is inserted to fit the pin 6 into the small diameter portion 4b of the sullar hole 4, there is no risk of the pin 6 falling off.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a link mechanism including a first link and a second link such as a cradle and an upper link of a circuit breaker.

[0002]

[Prior Art]

 As shown in FIG. 2, an upper end of an upper link 11 is pivotally attached to a cradle 10 of the circuit breaker by a pin 12, and an upper end of a lower link 13 is pivotally attached to the upper link 11 by a pin 14. Since the spring 15 constantly applies an upward force to the lower link 13, the cradle 10 always receives an upward force via the upper link 11.

Conventionally, the pivotally connecting portion between the cradle 10 and the upper link 11 has a structure in which both ends of the pin 14 are crimped as shown in FIG. However, this structure has a drawback in that it is not easy to assemble because the pin 14 crimping process is essential in the assembly process.

Therefore, as shown in FIG. 4, another structure has been proposed in which the upper end of the upper link 11 is cut out in a U shape and combined with the pin 14 having a king-shaped cross section so that caulking is unnecessary. .. In this structure, the large-diameter portion at the center of the pin 14 fits into the through hole of the cradle 10, and the small-diameter portions on both sides thereof fit into the upper end of the upper link 11. Since the upper link 11 pushes the pin 14 upward, there is no risk of the pin 14 coming off after assembly.

However, in the structure shown in FIG. 4, since both ends of the pin 14 project outward from the upper link 11, the head of the pin 14 is not particularly suitable in a device such as a circuit breaker that incorporates many parts in a narrow space. It was a hindrance, and there was a drawback that the spring space could not be taken sufficiently. In addition, since there was no upward force applied to the pin 14 during assembly, the pin 14 had a drawback that it could easily fall off.

[0006]

[Problems to be solved by the device]

 The present invention has been completed to solve the above-mentioned conventional problems and provide a link mechanism having two links, such as a cradle and an upper link, which is easy to assemble and has no protruding pin head. It is a thing.

[0007]

[Means for Solving the Problems]

 The present invention, which has been made to solve the above problems, provides a link mechanism in which a second link pivotally attached to a through hole of the first link by a pin presses the first link in a substantially constant direction. The through hole of is a large diameter part with a diameter equal to the diameter of the through hole of the second link, and both ends have the same diameter as the diameter of the through hole of the second link, and the center part uses a pin with the same diameter as the small diameter part of the radius hole. It is what

[0008]

【Example】

 Hereinafter, the present invention will be described in more detail with reference to the illustrated embodiments. In FIG. 1, 1 is a first link such as a cradle, 2 is a second link such as an upper link, and the second link 2 is a two-sheet structure that can be attached to both sides of the first link 1. There is. In the present invention, the first link 1 is provided with the daruma hole 4, but the diameter of the large diameter portion 4a thereof is substantially equal to the diameter of the through hole 5 of the second link 2.

Reference numeral 6 denotes a pin for pivotally connecting the first link 1 and the second link 2, the cross-sectional shape of which is an H-shape in which both end portions 6a have a large diameter and the central portion 6b has a small diameter. The diameters of both ends 6a of the pin 6 are substantially equal to the diameter of the through hole 5 of the second link 2, and the central portion 6b is substantially equal to the small diameter portion 4b of the dummy hole 4. However, a clearance that allows the pin 6 to be easily fitted is naturally required, and the term “equal” in this specification includes the clearance naturally required for this fitting.

[0010]

In order to assemble the link mechanism of the present invention having the above-described structure, first, the large diameter portion 4a of the sill hole 4 of the first link 1 and the through hole 5 of the second link 2 are aligned and assembled. Align and insert the pin 6 from the side. Then, after inserting the pin 6 until the end surfaces of both end portions 6a of the pin 6 are aligned with the outer surface of the second link 2, a force is applied to the second link 2 to move the pin 6 in the direction of the small diameter portion 4b of the round hole 4. Let As a result, the small-diameter central portion 6b of the pin 6 fits into the small-diameter portion 4b of the sullet hole 4, and the pin 6 can no longer come out even in the assembly process.

In addition, since the second link 2 presses the first link 1 in a substantially constant direction (in the direction of the small diameter portion 4b of the daruma hole 4) in the use state, there is no possibility that the pin 6 will fall off during use. The first link 1 and the second link 2 are securely pivoted by the pin 6.

[0012]

[Effect of the device]

 As described above, according to the link mechanism of the present invention, it is possible to securely pivotally attach the first link and the second link without the need for caulking both ends of the pin as in the conventional case. Moreover, this pin is unlikely to fall off during the assembly process, and the head of the pin does not project outside the second link. Therefore, the present invention is most suitable as a link mechanism composed of the first link and the second link such as the cradle and the upper link of the circuit breaker, but other general links used in the same manner. It goes without saying that the above can also be applied. Therefore, the present invention has an extremely great practical value as a link mechanism that solves the conventional problems.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

FIG. 2 is a sectional view showing a circuit breaker using the link mechanism of the present invention.

FIG. 3 is a plan view and a front view showing a conventional example.

FIG. 4 is a partially cutaway plan view and a front view showing a conventional example.

[Explanation of symbols]

 1 1st link 2 2nd link 4 Daruma hole 4a Large diameter part of Daruma hole 4b Small diameter part of Daruma hole 5 Through hole 6 Pin 6a Both ends of pin 6b Central part of pin

Claims (1)

[Scope of utility model registration request] 1. In a link mechanism in which a second link pivotally attached to a through hole of the first link by a pin presses the first link in a substantially constant direction, the through hole of the first link has a second large diameter portion
A link mechanism characterized in that a pin having the same diameter as the through-hole diameter of the link is used, and both ends thereof are equal to the diameter of the through-hole of the second link and the central portion thereof is equal to the small-diameter portion of the Daruma hole.