JPH0136255Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a throttle valve switch that detects the opening degree of a throttle valve installed in an intake system of an internal combustion engine.

Examples of conventional throttle valve switches include those shown in FIGS. 1A and 1B. To explain this, in FIG. 1A, the end of the rotating shaft of the throttle valve (not shown) is fitted into the hole 2a in the bottom wall of the case 1, which is attached to the outside wall of the engine's throttle valve (not shown). The shaft holder 2, which is engaged in a rotation-preventing manner, is rotatably supported. On the top surface of the flange portion 2b formed on the shaft holder 2, a metal section 3 having an arc shape and branched into two stages is attached with one end fixedly attached, and the other end rising from the top surface of the flange portion 2b. A pair of hemispherical contacts 3a and 3b are formed on the outside and inside to protrude in two directions.

Further, above the flange portion 2b of the shaft holder 2, an annular printed circuit board 4 is fixedly attached with its peripheral edge abutting against a stepped surface formed on the inner circumferential wall of the case 1.
The printed circuit board 4 has arcuate output side terminal plates 42A and 42B made of a metal material with excellent conductivity and wear resistance cut out in the circumferential direction on the bottom surface of a board body 41 made of an electrically insulating material such as epoxy resin. An arc-shaped metal plate 43 is fixed between the two output side terminal plates 42A and 42B with both ends separated therefrom. Also, the input side terminal board 4 is also arc-shaped.
4 are fixed to the inner peripheral sides of the output side terminal plates 42A, 42B and the metal plate 43, and these are arranged concentrically around the rotation axis of the throttle valve, and some of them are circumferentially aligned with each other. They are installed so that they overlap. In this attached state, the pair of contacts 3a, 3 of the metal section 3
b is in elastic pressure contact with the bottom surface of the printed circuit board 4, and when rotated together with the shaft holder 2, slides on the output side terminal plates 42A, 42B, the metal plate 43, and the input side terminal plate 44, respectively. There is. moreover,
Three wire-shaped electrode terminals 5 whose one end protrudes into a concave portion 1a formed on the outer circumferential wall of the case 1 and whose intermediate portions are cast and fixed into the wall of the case 1 are connected to the output side terminal plate 42A. , 42B and input side terminal board 44
Holes 42a, 42b, 4 formed at the right end in the figure
4a, and are electrically connected by soldering or the like.

For example, when the opening degree of the throttle valve is in the idling region of the engine and in the high load region, correspondingly, in the region where the output side terminal plates 42A, 42B and the input side terminal plate 44 overlap in the circumferential direction, A pair of contacts 3a and 3b are connected to the output side terminal board 4
2A or 42B and the input side terminal plate 44 at the same time, thereby the output side terminal plate 42A or 42B
and the input side terminal plate 44 are electrically connected via the metal piece 3, and the throttle valve is turned on, and in other areas, the outer peripheral side contact 3a is disconnected from the output side terminal plates 42A and 42B, and the throttle valve is turned off. Become. The ON/OFF signal of the throttle valve switch is input to a control circuit (not shown) connected to the electrode terminal 5, and a predetermined control is performed according to the opening degree of the throttle valve, that is, the load range of the engine. ing.

By the way, in such a conventional throttle valve switch, the contact 3a is connected to the output side terminal plate 42.
Contact 3 in the OFF region away from A and 42B
The metal plate 43 is provided to prevent wear caused by sliding between the contact 3a and the board body 41, and the contact 3a slides on this metal plate 43. Or, when passing through the gap between 42B and the metal plate 43, these terminal plates 42
The edges of A, 42B and the metal plate 43 are scratched and abraded, and in severe cases, they may be dug in by about 100 μm. The difference in level caused by the wear may cause a shift in the switching position of the switch, chattering during switching, or poor contact due to wear particles.

Furthermore, if the contact pressure of the contacts is made too low in order to suppress the wear, there is a risk that the contacts will separate from the terminal plate due to vibration.

The present invention was devised in view of these conventional problems, and is made by forming contacts made of arc-shaped metal pieces to have approximately the same width as the terminal plates and the metal plates provided between the terminal plates. In this configuration, the gap between the terminal plate and the metal plate is provided in a non-linear shape in the radial direction. By sliding and supporting the contacts, the contacts smoothly pass through the gap, thereby suppressing wear on the edge of the terminal plate, and preventing misalignment of the switch switching position, occurrence of chattering, and poor contact due to abrasion particles. It is an object of the present invention to provide a throttle valve switch that effectively prevents the occurrence of such occurrence.

The present invention will be explained below based on an embodiment shown in the drawings. However, in this embodiment, the same components as those in the conventional example will be described with the same reference numerals.

That is, in this embodiment, first, in the printed circuit board 6 shown in FIGS. 2A and 2B, the input side terminal plate 64 fixed to the bottom surface of the board body 61 is the same as the conventional one, but the pair of output side terminal plates 62A, 62B and the metal plate 63 provided between these output side terminal plates 62A, 62B, the gaps C ₁ and C ₂ are bent in the radial direction so as to be non-linear.

On the other hand, as shown in FIG. Brush-like contacts 7a and 7b having the same width as the output side terminal plates 62A and 62B and the metal plate 63 are provided by making cuts. however,
The contact point on the inner peripheral side of the metal piece 7 may be formed by a hemispherical protrusion as in the conventional case.

Other configurations are the same as before, and each part is assembled in the same manner as shown in Figure 1.
The action will be explained with reference to FIG. 1 as well.

That is, due to the rotation of the throttle valve, the metal piece 7 rotates together with the shaft holder 2, and the output side terminal plate 6
2A or 62B and the input side terminal plate 63 overlap in the circumferential direction, the pair of contacts 7a, 7b of the metal section 7 connects to the output side terminal plate 62A or 62.
2B and the input side terminal board 63 at the same time and the switch is turned on, as in the conventional case.

Next, the operation when the contact 7a on the outer peripheral side passes through the gaps C ₁ and C ₂ will be explained using the case where it moves from the output side terminal plate 62A to the metal plate 63 as an example.

In FIG. 2B, when the contact 7a moves in the section a, the brush-like contact 7a partially connects the output terminal plate 62A or the output terminal plate 62A and the metal plate 6.
3, and the switch is kept ON during this time. On the other hand, when the contact 7a moves through the section b, the inner and outer peripheral parts of the contact 7a slide on the metal plate 63 and are removed from the output terminal plate 62A, so the switch is not activated.
It becomes OFF.

In this way, when the contact 7a passes through a certain section of the gap _C1 , a part of it slides on and is supported by at least one of the output side terminal plate 62A and the metal plate 63, so that the gap between the other parts is reduced. _C1 can be suppressed, and as a result, wear of the edges of the output side terminal plate 62A and the metal plate 63 due to the contact 7a can be suppressed to a greater extent than in the past.

Therefore, it is possible to effectively prevent the shift of the switching position of the switch, the occurrence of chattering, and poor contact due to wear particles caused by the wear.

Further, since the contact 7a is cut into a brush shape, its elasticity allows it to effectively contact a part of the output terminal plate 62A, thereby stably maintaining the switch operation.

The same is true when the contact 7a passes through the gap _C2 ,
Output side terminal plate 62B and metal plate 63 adjacent thereto
The same functions as those described above can be obtained by effectively suppressing the wear of the edges of the blade.

As explained above, according to the present invention, the contacts of the metal piece sliding on the metal plate provided in the OFF section between the terminal plate on the output side or the input side separated in the circumferential direction are connected to the terminal plate and the metal plate. The terminal plate is formed to have approximately the same width as the plate, and the gap between the terminal plate and the metal plate is provided so that it is non-linear in the radial direction, so that when the contact passes through the gap, a part of it will be connected to the terminal. Since it slides on and is supported by at least one of the terminal plate and the metal plate, it is possible to suppress the wear of the edges of the terminal plate and the metal plate when they pass through the contact point, thereby preventing the shift of the switching position of the switch due to such wear. It is possible to effectively prevent occurrence of chattering and poor contact due to abrasion powder, and maintain stable switch operation.

[Brief explanation of the drawing]

FIG. 1A is a sectional view showing an example of a conventional throttle valve switch, FIG. 1B is a bottom view showing a printed circuit board used in the above switch, and FIG. Bottom view of the printed circuit board used for the tutle valve switch, Figure B
1 is an enlarged view of part B of FIG. 1A, and FIG. DESCRIPTION OF SYMBOLS 1... Case, 2... Shaft holder, 6... Printed circuit board, 7... Metal section, 7a... Contact, 61...
... Board main body, 62A, 62B ... Output side terminal board,
63...Metal plate, 64...Input side terminal board.

Claims (1)

[Scope of utility model registration request] A case attached to the outer wall of a throttle valve chamber of an internal combustion engine, a shaft holder rotatably supported by the case and engaged with an end of the rotating shaft of the throttle valve, and one end attached to the flange surface of the shaft holder. A plate spring-like metal piece is fixed to the metal piece and a pair of contacts are formed at the other end, and metal arc-shaped output side and input side terminals are fixed to the case and are fixed to the surface of the board body made of an electrically insulating material. The plates are arranged concentrically with the center of the throttle valve, and one terminal plate is radially cut off and fixed to a plurality of pieces, and an arc-shaped metal plate is placed between the separated terminal plates and spaced apart from both ends of the terminal plate. A pair of contacts elastically pressed against the surface of the printed circuit board will turn ON when they simultaneously contact the output side and input side terminal boards when the throttle valve is rotating, and turn OFF at other times. In a throttle valve switch configured to 1. A throttle valve switch characterized in that the terminal plate and the metal plate are formed substantially the same, and the gap between the terminal plate and the metal plate is provided so as to be non-linear in the radial direction.