JPH06216399A - Plating jig for hermetic terminal of pressure sensor - Google Patents

Abstract

PURPOSE:To reduce a depositing amount of a plating material to a dummy sphere when a lead of a hermetic terminal of a pressure sensor is barrel plated, to make a thickness of a plating film uniform, and to prevent bents, entanglement of leads. CONSTITUTION:A body of a plating jig 20 is formed of a hollow conical support structure 21 made of a nonconductive material disposed under a metal outer ring 1 and a pin structure 22 mounted as a positioning support member of a pressure guide pipe 6 at a lower end of the structure 21. A ring 24 made of a conductive material or a partition block made of a nonconductive material is fixed as a positioning fixed material of a lead 3 on an outer periphery of an upper end of the structure 21.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plating jig for an airtight terminal for a pressure sensor.

[0002]

2. Description of the Related Art A general structure and function of an airtight terminal for a pressure sensor will be described with reference to FIGS. The airtight terminal (15) is obtained by crimping the lower end flange portion (13A) of the iron cap (13) having a substantially uniform thickness to the outer peripheral step (1A) of the metal outer ring (1) such as 42 alloy or Kovar. , In this state, energize to supply the metal outer ring (1) and the iron cap (13).
By welding, the sealing space (7) of the pressure sensitive element (9) is formed between the metal outer ring (1) and the iron cap (13). An air supply port (5) consisting of a through hole is provided in the axial center portion of the metal outer ring (1), and an Au plating layer is formed on the lower surface of the metal outer ring (1) so as to communicate with the air supply port. The pressure guiding pipe (6) is brazed using (not shown) as a joining medium. On the other hand, in the axial center part of the upper surface of the metal outer ring (1), a tubular pedestal (8) made of Si is taken into consideration in consideration of the difference in coefficient of thermal expansion between the pressure sensitive element (9) made of Si and the metal outer ring (1). A resistance pattern (9A) is formed on the upper surface of the tubular pedestal (8) and an Au plating layer (11) is formed on the back surface.
The pressure-sensitive element (9) formed by forming is deposited by utilizing the eutectic structure of Au-Si. The lead wire (3) is hermetically sealed to the metal outer ring (1) by the glass (4). The pressure of the air in the sealed space (7) of the pressure sensitive element (9) is maintained at a constant value P1, and the pressure sensitive element (9) passes through the pressure guiding pipe (6) and the air supply port (5). The variable pressure of the air sent to the back side is P2, and the change in the pressure P2 is detected from the distortion of the resistance pattern (9A) due to the difference between P1 and P2 by utilizing the change in the impedance of the bridge circuit.

In the process of manufacturing the airtight terminal (15) for the pressure sensor, the pressure sensitive element (9) and the iron cap (13) are attached to the metal outer ring (1).
Prior to the mounting of the lead wire (3), the lead wire (3) sealed by the glass (4), for the purpose of improving the solderability, an underplating consisting of Ni electroplating or Ni electroless plating, Finish plating consisting of electroplating of Au is applied. As the electroplating method of Au,
A barrel plating method is used in which electrical continuity is secured with a dummy ball.

[0004]

When the barrel plating method is adopted as the plating means for the lead wire (3), the first problem is that a plating film is formed on the surface of the lead wire (3) under the interposition of a dummy ball. As a result, a plating film is formed on the dummy spheres, which requires a recovery process.
In addition, the electrical continuity of the dummy balls between the lead wires is likely to be non-uniform, and a large number of lead wires (3) are not held at the same potential within the single airtight terminal (15) for the pressure sensor,
Since the plating may be performed individually, there is a problem that the thickness of the plated coating becomes uneven between the lead wires (3).

Further, as a second problem in the case where the barrel plating method is adopted, the lead wire (3) is entangled among a large number of airtight terminals (15) because the plating is performed while positioning and fixing are unstable. It can be mentioned that quality defects such as curvature and breakage occur.

[0006]

As a first means for solving the above problems, the present invention provides a support structure for an airtight terminal body, which is used when barrel-plating a lead wire of an airtight terminal for a pressure sensor, with a metal outer ring. A hollow conical support structure made of a non-conductive material disposed below as a supporting member, a pin structure attached to a lower end of the hollow conical supporting structure as a positioning support member for a pressure guiding pipe, and the hollow cone. -Shaped cushion material that is made of elastic rubber and is fitted in the upper end opening of the cylindrical support structure and has a pressure guide pipe insertion hole at the center, and support of the lead wire on the upper outer peripheral surface of the hollow conical support structure. The present invention provides a plating jig for an airtight terminal for a pressure sensor, which is composed of a ring made of a conductive metal material that is fixed to face the annular cushion material as an assembly.

As a means for solving the above-mentioned second problem, according to the present invention, a supporting structure of a hermetic terminal body used when barrel-plating a lead wire of a hermetic terminal for a pressure sensor is provided below a metal outer ring. A hollow conical support structure made of a non-conductive material formed by forming a large number of pores for distributing a plating solution on the wall surface of the support member arranged as a support member, and a pressure guiding member at the lower end of the hollow conical support structure. A pin structure mounted as a positioning support member for the pipe, and a partition block made of a non-conductive material fixed on the outer peripheral surface of the upper portion of the hollow conical support structure as a lead wire spacing structure at a predetermined circumferential pitch. A plating jig for an airtight terminal for a pressure sensor configured by

[0008]

In the plating jig according to the present invention, the lower surface of the metal outer ring is brought into contact with the upper surface of the hollow conical support structure, and the lower end of the pressure guiding pipe is fitted into the pin structure. Apply barrel plating. At this time, the lead wire, which is glass-sealed to the body of the airtight terminal, adheres to the ring made of a conductive metal material by utilizing the elastic pressing force of the annular cushion material to hold the plurality of lead wires at the same potential. . As a result, the plated coating of the lead wire has a uniform thickness, and
The amount of plating on the dummy ball is reduced.

On the other hand, in the plating jigs according to claims 1 and 3, the procedure for fixing the pressure guiding pipe is the same as that of the plating jig according to claims 1 and 2, but the body of the hermetic terminal is sealed with glass. The plurality of attached lead wires fits between the partition blocks around the hollow conical support structure. By performing barrel plating in this state, the lead wire is protected by the partition block, and the plating processing condition that does not cause quality defects such as bending and breakage is secured.

[0010]

[Example] [Example 1]

A first embodiment of the present invention will be described below with reference to FIG. In the following description, the same components as those of FIG. 3 showing the conventional technique are denoted by the same reference numerals, and the description of the overlapping matters will be omitted. The plating jig (20) for the airtight terminal (15) for a pressure sensor is a non-conductive material that supports the metal outer ring (1) from below when the airtight terminal (15) is mounted on the jig (20). And a pin structure (22) fixed to the lower end of the hollow conical support structure (21) as a positioning support member for the pressure guiding pipe (6). Then, at the upper end opening of the hollow conical support structure (21), an annular cushion material (23) made of elastic rubber, for example, Si rubber, having an insertion hole (6A) of the pressure guiding pipe (6) opened at the center. ) Is fitted and correspondingly, on the outer peripheral surface of the upper part of the hollow conical support structure (21), a conductive metal material, for example, a Fe-Ni alloy wire is used as a support structure for the lead wire (3). The ring (24) consisting of is fixed.

When the lower surface of the metal outer ring (1) is brought into contact with the upper surface of the hollow conical support structure (21) and the lower end of the pressure guiding pipe (6) is fitted into the pin structure (22), an airtight terminal ( The lead wire (3), which is glass-sealed to the body of (15), is brought into close contact with the ring (24) by utilizing the elastic pressing force (indicated by a white arrow F) of the annular cushion material (23). . By forming the hollow conical support structure (21) from a non-conductive material, the amount of plating on the dummy sphere is reduced, the number of recovery steps is reduced, and the metal outer ring (1) is glass-sealed (4). All the lead wires (3) present are held at the same potential by the ring (24) during barrel plating. As a result, the lead wire (3)
An Au plating film having a uniform thickness is formed on the surface of the. The support by the ring (24) also prevents the lead wire (3) from being damaged due to bending or entanglement.

In the hollow conical support structure (21), in order to facilitate the deformation of the annular cushion material (23) in the radial direction and the generation of elastic pressure (F) due to it, the direction of the generatrix A slit (not shown) is provided along the line.

[Embodiment 2]

A second embodiment of the present invention will be described below with reference to FIG. In this second embodiment, the annular cushion material (23) described in the first embodiment is not attached to the upper opening of the hollow conical support structure (21), but the hollow conical support structure (21) is ), The lower surface of the metal outer ring (1) is supported, and the lower end of the pressure guiding pipe (6) is fitted into the pin structure (22) to position and fix the body of the airtight terminal (15). This is the same as the first embodiment.

The difference from the first embodiment is that the hollow conical support structure (21) is provided with a large number of pores (25) for circulating the plating solution in the wall surface of the hollow conical support structure (21) and the hollow conical support structure (21). ), A partition block (26) made of a non-conductive material is fixed to the outer peripheral surface of the upper part of the lead wire (3) at a predetermined circumferential pitch as a space structure for the lead wire (3).

A second airtight terminal (15) having the above structure
When mounted on the plating jig (27), the plurality of lead wires (3) are fitted between the partition blocks (26) around the hollow conical support structure (21). Barrel plating is applied in this state, but the lead wire (3) is fitted between two adjacent partition blocks (26) to protect it from damage due to bending or entanglement. Further, by forming the partition block (26) and the hollow conical support structure (21) from a non-conductive material, the amount of plating on the dummy sphere is reduced,
The number of man-hours for recovering the plating material, for example Au, is reduced.

[0018]

When the plating jig (20) according to claims 1 and 2 is used, the lead wire (3) is supported by the ring (24) made of a conductive material, so that the lead wire ( 3) Bending and entanglement are prevented, and a plurality of lead wires (3) glass-sealed to the metal outer ring (1) are held at the same potential as a constituent member of the pressure sensor airtight terminal (15). To be done. As a result, the thickness of the plated coating becomes uniform. By forming most of the main body of the plating jig (20) from a non-conductive material, the amount of plating on the dummy balls is also reduced.

On the other hand, when the plating jig (27) according to claims 1 and 3 is used, individual lead wires (3)
By being fitted between the two partition blocks (26), a great effect is exhibited in preventing the occurrence of quality defects such as bending and entanglement. Furthermore, by forming the main body of the plating jig (27) from a non-conductive material, the amount of plating on the dummy balls is reduced, and the effect of reducing the number of man-hours for collecting the plating material, for example Au, is exerted.

[Brief description of drawings]

FIG. 1A is a front view showing a first embodiment of a plating jig according to the present invention, and FIG. 1B is a front view of an airtight terminal for a pressure sensor mounted on the plating jig.

2A is a perspective view showing a second embodiment of a plating jig according to the present invention, FIG. 2B is a longitudinal sectional view thereof, and FIG. 2C is an airtight terminal for a pressure sensor mounted on the plating jig. Front view of

FIG. 3A is a vertical cross-sectional view showing a general structure of an airtight terminal for a pressure sensor, and FIG. 3B is a top view thereof.

[Explanation of symbols]

 1 Metal outer ring 3 Lead wire 6 Pressure pipe 15 Airtight terminal for pressure sensor 20 Plating jig 21 Hollow conical support structure 22 Pin structure 23 Annular cushion material 24 Ring 25 Pore 26 Partition block 27 Plating jig

Claims (3)

[Claims] 1. A metal outer ring and a metal cap fixed to the metal outer ring, wherein a lead wire is sealed to the metal outer ring,
Barrel plating is applied to the lead wire of the pressure-tight terminal for a pressure sensor, in which a pressure sensitive element is built in the space sealed by the cap, and a pressure guiding pipe is brazed to the lower surface of the metal outer ring. A supporting structure for an airtight terminal body used in this case, the supporting structure having a hollow conical shape made of a non-conductive material, which is arranged below the metal outer ring, and the above-mentioned pressure guiding member at the lower end of this supporting structure. A pin jig mounted as a positioning and supporting member for a pipe, and a plating jig for an airtight terminal for a pressure sensor. 2. The plating jig according to claim 1,
On the upper end opening of the hollow conical support structure, an elastic rubber annular cushion material having an insertion hole of the pressure guiding pipe opened at the center is fitted, and on the upper outer peripheral surface of the hollow conical support structure. A plating jig for an airtight terminal for a pressure sensor, wherein a ring made of a conductive metal material is fixed to the annular cushion material as a support structure for the lead wire in a state of being opposed to the annular cushion material. 3. The plating jig according to claim 1, wherein
A large number of pores for circulating the plating solution are formed on the wall surface of the hollow conical support structure, and a predetermined circumference is provided on the outer peripheral surface of the upper part of the hollow conical support structure as a structure for separating the lead wires. A plating jig for airtight terminals for pressure sensors, characterized in that partition blocks made of a non-conductive material are fixed at a pitch in the direction.