JP3080360B2 - Terminal crimping method and terminal crimping tool - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for crimping a terminal to a conductor of electric wiring and a terminal crimping tool suitable for the method.

[0002]

2. Description of the Related Art In general, electric wires and terminals are formed by crimping, which is a simple fixing technique. This is because the fixation is performed at the wiring work site. A conventional terminal crimping tool includes a die fixed to a cylinder of a piston via a bracket, and a punch fixed to a ram of the piston. At the time of crimping, the terminal of the electric wiring through which the conducting wire is passed is sandwiched between a die and a punch, and the punch is pressed against the terminal by a driving force such as an oil pressure to plastically deform the terminal.

In this conventional tool, the oil pressure has been required to be higher than a certain value. This is because the electrical resistance between the terminal and the conductor after crimping is specified in Japanese Industrial Standards in order to prevent a poor electrical connection between the terminal and the conductor.

[0004]

As described above, since the bonding between the conductor and the terminal is performed at the wiring work site, the lighter the terminal crimping tool, the easier it is to handle. However, in the case of the conventional tool, the size of the piston must be larger than a certain value in order to make the above-mentioned oil pressure be a certain value or more, and there is a limit to miniaturization. Therefore, an object of the present invention is to provide a crimping method for reducing the size and weight of a terminal crimping tool and a terminal crimping tool that is reduced in size and weight.

[0005]

In order to achieve the object, a terminal crimping method according to the present invention is characterized in that a terminal of an electric wiring through which a conductor is passed is sandwiched between a die and a punch, and the punch is moved toward the die together with a ram of a piston. In the method of crimping the terminal to the conductor by relatively moving the terminal, the terminal is crimped to a different portion of the terminal each time a plurality of crimping operations are performed.

According to the method of the present invention, the fixing between the terminal and the punch is completed by individually applying pressure to a plurality of portions of the terminal. Therefore, even if the contact area between the terminal and the conductor wire per one place is small, if the total contact area of the plurality of places is larger than the contact area by the conventional method, the conduction of the crimped portion is sufficiently ensured. Therefore, the amount of plastic deformation of the terminal per operation may be small, and the hydraulic pressure can be reduced accordingly.

A plurality of crimping operations are performed with one crimping tool,
In order to crimp the terminal to a different place each time, a plurality of rams may be connected to one pump in parallel. However, in the crimping method of the present invention, the contact point with the terminal of the punch is provided at a position eccentric from the axis of the ram, and after the crimping, the punch is separated from the terminal, and the punch is rotated about the axis of the ram and crimped again. Things. This way,
This is because only one ram is required, and the entire tool can be reduced in size. According to the method of the present invention , since the contact with the terminal of the punch is at a position eccentric from the axis of the ram and the punch rotates between the first crimping operation and the second crimping operation,
The terminal is plastically deformed at two places. This is different from the conventional tool in which the punch has an axially symmetrical shape and the crimping operation is completed only once.

A tool suitable for the above-mentioned preferred means of the present invention comprises a die and a punch which can be relatively moved across a terminal of an electric wiring through which a conductor is passed, and a piston for transmitting a driving force to the punch, and And a joint that connects the ram of the piston and the punch, and that linearly moves with the ram and is rotatable around the axis of the ram, wherein the punch is fixed to the joint. The contact with the terminal is provided at a position eccentric from the axis of the ram.

According to this tool, the first crimping operation and 2
During the second crimping operation, the joint rotates with the punch,
The punch contacts the different portions of the terminal between the first time and the second time. Therefore, the terminal can be plastically deformed at two places.

[0010]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view illustrating a terminal crimping tool according to an embodiment, and FIG. 2 is a diagram illustrating a crimping method according to the embodiment.
3A and 3B show a punch used in the embodiment of FIG. 1, wherein FIG. 3A is a plan view, FIG. 3B is a front view, and FIG. 3C is a right side view.

The terminal crimping tool 1 includes a die 2, a punch 3,
A punch driving source and a body 4 incorporating the driving source are provided. A small handle 41 and a large handle 42 are attached to the body 4 so as to be angled with respect to its axis. The small handle 41 has an oil tank 43 and the large handle 4
2 has a built-in battery 44. A motor 45 connected to a battery 44 and a plunger pump (not shown) connected to the oil tank 43 are built in the center of the body 4. In this example, the electric motor 45 and the plunger pump are drive sources.

When crimping using the tool 1, the die 2
And the punch 3 sandwich the terminal T, and as shown in FIG.
The punch 3 is moved toward the die 2 with the conducting wire W passing through the rear part of the terminal T, and a first impression F is made by the punch 3 on the rear part of the terminal T. The punch 3 has a trapezoidal protrusion 31 at a position eccentric from the axis center line. Therefore, the indentation F is the convex portion 31
And a shape complementary to After the indentation F is formed, the hydraulic pressure is released in order to separate the punch 3 from the terminal T, and the punch 3 is rotated by 180 ° around the axis while temporarily returning. The punch 3 is moved toward the die 2 again. Then, a second indentation S having the same shape is provided at a position symmetrical to the first indentation F. Thus, the conductive wire W is fixed to the terminal T by being tightened by the two indentations F and S.

Next, details of the internal mechanism of the tool 1 for transmitting the driving force to the punch 3 will be described with reference to FIGS. FIG. 4 is a fragmentary front view of a terminal crimping tool. FIG.
1 shows a joint used in the embodiment of FIG. 1, (a) is a front view, (b) is a left side view, (c) is a bottom view, and (d) is a dd sectional view of (c).

The body 4 has a piston at a substantially central portion, and a ram 6 which is operated by the plunger pump is built in a cylinder 5 thereof. A forked bracket 7 for attaching the die 2 is fixed to the cylinder 5. An oil reservoir 61 is provided at the center of the ram 6, and the oil introduction pipe 8 is inserted into the oil reservoir 61.
Therefore, the initial movement of the ram 6 is performed by the oil that fills the oil reservoir 61 through the oil introduction pipe 8. Thereafter, the following oil enters the gap between the rear end face 62 of the ram 6 and the bottom surface of the cylinder 5 to further advance the ram 6.

An annular groove 63 is formed in the rear part of the outer periphery of the ram 6. The ram 6 is fitted with a tubular joint 9 extending forward, and the tip of a pin 91 penetrating through the joint 9 in the radial direction enters the groove 63 to prevent the joint 9 from coming off. The joint 9 is supported by a guide portion 71 protruding inside the bracket 7. However, the joint 9 is rotatable around the axis while sliding on the ram 6 and the guide portion 71. At this time, the tip of the pin 91 also runs in the groove 63 in the circumferential direction. A spring 64 for biasing the ram 6 rearward is provided around the joint 9. Spring 64
Always holds the ram 6 at the most retracted position.
When the hydraulic pressure is released, the ram 6 advances together with the joint 9 against the elasticity of the spring 64 (going to the left in FIG. 4).
Due to the elasticity of 4, the ram 6 moves back together with the joint 9 to the original position.

The joint 9 has two long grooves 92 and 93 extending in the axial direction, and the two long grooves 92 and 93 are connected to each other so that X
Two cross grooves 94 and 95 intersecting in a letter shape are formed. Further, the joint 9 has a high step 9 on the punch side at the ram side junction with the cross grooves 94 and 95 in the long grooves 92 and 93.
6,97. The punch-side end points of the long grooves 92 and 93 coincide with the punch-side junction with the cross grooves 94 and 95. A guide pin 72 radially penetrates the guide portion 71 of the bracket 7 at any position of each of the grooves 92, 93, 94, 95 so that the leading end of the guide pin 72 meshes with the guide portion 71.
Therefore, the joint 9 moves straight or rotates while being regulated by the guide pin 72. That is, when viewed from the joint 9, the guide pin 72 moves along the bottom surface of the groove as the ram 6 reciprocates. In addition, the guide pin 72 is always used.
Are the long grooves 92 (93) and the cross grooves 94 (9)
5) is at the junction with the punch side. Through-hole 98 of joint 9
Is for inserting the pin 91.

The punch 3 is inserted into the joint 9 and is prevented from coming off by a pin 32 penetrating the joint 9 in the radial direction.
The through hole 33 of the joint 9 is for inserting the pin 32. Accordingly, the punch 3 moves with the ram 6 and the joint 9 as follows. However, the punch 3 and the joint 9 may be connected to each other by providing a concave portion on the rear end surface of the punch 3 and fitting the convex portion of the distal end of the joint 9 to the concave portion, contrary to the present embodiment.

When the ram 6 moves forward together with the punch 3 and the joint 9, the guide pin 72 slides on the bottom surface of the long groove 92 (), and stops when it comes into contact with the end point. Thereafter, the ram 6 moves back together with the punch 3 and the joint 9 (). The guide pin 72 hits the step 96 on the way, so that the guide pin 72 is aligned with the cross groove 94 ().
The joint 9 rotates while retreating. Therefore, the punch 3 moves backward while drawing a spiral trajectory. When the guide pin 72 comes into contact with the punch-side end point of the long groove 93, the first crimping operation ends. At this time, the protrusion 31 of the punch 3
Is at a position rotated 180 ° around the axis from the initial position. Subsequently, the ram 6 advances again to start the second crimping operation. The guide pin 72 slides on the bottom surface of the long groove 93 ().
7, the joint 9 rotates while retreating so that the guide pin 72 is along the cross groove 95. When the guide pin 72 returns to the end point of the long groove 92, the second crimping operation ends. The protrusion 31 has also returned to the initial position.

As described above, according to the tool 1, the punch 3 of the terminal T is used in the first crimping operation and the second crimping operation.
The contact with changes. Therefore, indentations can be continuously formed at two different positions of the terminal with one cylinder. As a result, the contact area between the conductive wire W and the terminal T increases, so that the hydraulic pressure required for one press bonding may be small, and the cylinder can be downsized.

[0020]

According to the present invention, the terminal is plastically deformed at two places.
The amount of plastic deformation of the terminal per turn may be small, and the fluid (eg, oil) pressure can be reduced accordingly. As a result, the size of the pump as a pressure source can be reduced, and the entire tool can be reduced in size and weight.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a terminal crimping tool according to an embodiment.

FIG. 2 is a diagram illustrating a terminal crimping method according to the embodiment.

3A and 3B show a punch applied to the terminal crimping tool of the embodiment, wherein FIG. 3A is a plan view, FIG. 3B is a front view, and FIG. 3C is a right side view.

FIG. 4 is a fragmentary front view showing an internal mechanism of the terminal crimping tool according to the embodiment.

5A and 5B show a joint applied to the terminal crimping tool of the embodiment, wherein FIG. 5A is a front view, FIG. 5B is a left side view, FIG. 5C is a bottom view, and FIG. It is.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Terminal crimping tool 2 ... Die 3 ... Punch 31 ... Convex part 32 ... Pin 4 ... Body 41 ... Small handle 42 ... Large handle 43 ... Oil tank 44 ... Battery 45 ... Motor 5 ... Cylinder 6 ... Ram 61 ... Oil reservoir 62 ... Rear end face 63 ... Circumferential groove 7 ... Bracket 71 ... Guide part 8 ... Oil introduction pipe 9 ... Joint 91 ... Pin 92,93 ... Long groove 94,95 ... Cross groove 96,97 ... Step

Claims (4)

(57) [Claims] 1. A sandwiched terminal conductors through electric wiring die and punch, by the punch with the piston of the ram relative movement towards the die, a method of crimping a terminal to the wire, the terminal of the punch Eccentric from the ram axis
Position, release the punch from the terminal after crimping, and
Rotating the punch around the wire and crimping again
More, a terminal crimping method characterized by crimping a plurality of times each time different locations terminals for each of the crimping operation. 2. A device comprising: a die and a punch capable of relatively moving across a terminal of an electric wiring through which a lead is passed; and a piston for transmitting a driving force to the punch, and crimping the terminal to the lead. And a joint that moves linearly with the ram and is rotatable around the axis of the ram, the punch is fixed to the joint, and the contact point with the terminal is connected to the axis of the ram. A terminal crimping tool provided at a position eccentric from the terminal. 3. The joint has a groove formed on an outer peripheral surface thereof, and the terminal crimping tool further comprises a guide pin fixed radially to a cylinder of the piston such that a tip thereof contacts a bottom surface of the groove. 3. The terminal crimping tool according to claim 2 , further comprising: a rotation movement and a linear movement of the joint are regulated by the guide pin. 4. The groove comprises two long grooves parallel to each other in the axial direction and two cross grooves connected to the two long grooves and intersecting with each other, and the long grooves have a high step on the punch side as a cross groove. The terminal crimping tool according to claim 3, which is provided at a ram-side confluence point, and the punch-side end portion coincides with the punch-side confluence point with the cross groove.