JP4514701B2 - Rotation detection sensor - Google Patents

Description

  The present invention relates to a rotation detection sensor such as an automobile wheel speed sensor or an engine speed sensor.

For example, in the wheel speed sensor P, as shown in FIG. 9, the detection part a is mounted (provided) on a resin holder (bobbin) 2 and the detection part a is mounted in the covered cylindrical casing 1 from its opening. The output cable 6 is connected to the relay terminal 5 connected to the lead piece (lead terminal) 12 from the detection portion a and led out from the end surface of the holder base, and the casing opening and the holder exposure portion are connected. The relay terminal 5 and a part of the output cable 6 are embedded over the entire circumference to cover the resin 4 (see Patent Document 1).
Further, there is also a case in which the detection part a is not directly mounted on the casing 1 but the detection part a is directly coated with the resin 4 or the output cable 6 is directly connected to the lead piece 12 without the relay terminal 5 being interposed. Yes (see Patent Documents 2 and 3).
JP 2002-257840 A JP 2003-57259 A JP 2003-66057 A

  As shown in FIG. 10, a lead piece 12 is led out in parallel to a rotation detecting element 11 such as a Hall IC that detects magnetic field fluctuations, and an electron such as a capacitor is provided between the two lead pieces 12 and 12. Some are provided with a component 13.

  The lead piece 12 of the detection part a is connected to the relay terminal 5 inserted in the holder 2 by spot welding such as resistance welding. At this time, the Hall IC 11 is fitted in the hole 2 c of the holder 2, and the protrusion 2 d of the holder is fitted between the lead pieces 12, 12, so that the detection part a is positioned in the holder 2. A synthetic resin lid 7 is fitted into the holder 2.

  As shown in FIG. 9, the wheel speed sensor P is provided so as to face the rotating detection object B, detects a magnetic field variation due to rotation of the detection object B by the detection unit a, and converts it into an electrical signal. The signal is transmitted to an external control device via the relay terminal 5 and the output cable 6. The detected body B has a ferromagnetic pulsar ring provided with gear-like teeth at the peripheral edge, or a magnet magnetized so that S and N poles appear alternately and continuously on the peripheral surface. Pulsar ring is used. In this example, since the magnet 3 is provided in the holder 2, a ferromagnetic pulsar ring is employed.

In manufacturing this type of wheel speed sensor P, when the detection portion a is directly resin-coated 4 without mounting the detection portion a on the casing 1, the coating resin is between the rotation detection element 11 and the holder 2. May get in.
Conventionally, a holder 2 is provided with a claw or the like that engages with the lead piece 12 and the movement of the detection portion a is prevented by the claw, but there is no one that directly prevents the rotation detection element 11 from moving.

For this reason, when the coating resin enters between the rotation detection element 11 and the holder 2, the rotation detection element 11 moves due to the penetration of the resin, and a part of the rotation detection element 11 is exposed from the resin coating 4. The resin coating 4 around the rotation detection element 11 may be thinner than a predetermined thickness.
If the rotation detecting element 11 is exposed, the airtightness of the rotation detecting element 11 is lost and a problem occurs in detection accuracy. Further, if the resin coating 4 becomes thin, cracks are likely to occur in the resin coating 4 due to vibration or the like, and due to the growth of the cracks, the hermeticity is deteriorated, which also causes a problem in detection accuracy.

  An object of the present invention is to reliably prevent the movement of the rotation detecting element due to resin coating.

In order to achieve the above object, according to the present invention, the holder is provided with a claw for directly preventing the movement of the rotation detecting element.
In this way, the rotation detecting element is positioned by the claw and its movement is prevented directly, so that the coating resin is difficult to enter between the rotation detecting element and the holder. Even if it enters, the rotation detecting element is positioned. Does not move from position.

  According to this invention, since the movement of the rotation detection element due to the resin coating is reliably prevented, the rotation detection element is not exposed, and the resin coating is not thinned and the resin coating is not easily cracked. In addition, there is no problem in detection accuracy due to deterioration of hermeticity.

  As an embodiment of the present invention, a rotation detection element that detects a magnetic field variation due to rotation of a detected object and converts it into an electrical signal is attached to a holder, and output from the rotation detection element via a pair of lead terminals of the rotation detection element In the rotation detection sensor in which the cable is pulled out and the rotation detection element, the lead terminal, the entire holder and a part of the output cable are embedded and resin-coated, a recess for fitting the rotation detection element is formed in the holder. In addition, it is possible to employ a configuration in which a locking claw that locks the rotation detection element and prevents the rotation detection element from floating is provided.

In this configuration, the locking claw may be provided only on one side of the rotation detection element as long as it can be prevented from lifting by only locking one side of the rotation detection element. The prevention action is more certain.
As shown in FIG. 9, the rotation detection element has a lead terminal bent in a U-shape, or as disclosed in Patent Document 2 and FIG. 3, with the lead terminal extending straight from the rotation detection element. In the case of the latter linear lead terminal, if the coating resin enters between the rotation detection element or the lead terminal and the holder, the entry directly relates to the rise of the rotation detection element. The action of is more effective.

  By the way, when the lead terminal has a dogleg shape, when the coating resin enters between the rotation detection element or the lead terminal and the holder, the insertion is the direction in which the other (lead terminal or rotation detection element) is pressed against the bottom surface of the fitting hole. As a result, the detection unit is rarely lifted.

Preferably, the holder is provided with a partition wall between the connecting portions of the pair of lead terminals and the pair of core wires of the output cable to prevent contact between the two, thereby preventing short-circuiting of the core wires. Furthermore, it is preferable to provide a concave portion for preventing escape of heat when soldering the connection portion in the holder that contacts the back surface of the lead terminal of both the connection portions so that the soldering can be surely performed. . At that time, a notch can be provided on the surface of the partition wall facing both connecting portions so that the soldering fillet can be easily seen from the outside and the soldering inspection can be easily performed.

  Also, the holder is provided with walls located on both sides of the connecting portion between the pair of lead terminals and the pair of core wires of the output cable to prevent the outside of the core wire from being connected, and a part of the core wire is connected. It is preferable to prevent the resin coating from protruding from the portion and being exposed to the outer surface to cause deterioration of airtightness, causing cracks, or shorting between the core wires.

  Further, a protrusion is provided on the inner side surface of the wall, and the surface of the protrusion on the partition side is an inclined surface that approaches the partition toward the inside of the pocket portion between the wall and the partition, and the core wire is formed in the pocket portion. As inserted, the core wire can be brought closer to the partition wall by the inclined surface of the projection, and can be surely along the partition wall. If the core wire reliably follows the partition, positioning with the lead terminal of the rotation detecting element becomes easy.

This type of rotation detection sensor is attached to a wheel hub or the like as a vehicle wheel speed sensor. In this case, a positioning rib is provided on the outer peripheral surface of the resin coating in order to attach it accurately. On the other hand, the resin coating is usually formed by combining two or more dies, and at this time, a parting line of the split surface is formed on the outer surface of the resin coating of the split surface of each mold.
If the positioning rib is aligned with the parting line, if the burr occurs on the parting line, the burr will obscure the positioning rib, so that the rotation detection sensor can be mounted accurately. Disappear.
For this reason, it is preferable that the positioning rib be positioned at a position different from the parting line of the mold.

An embodiment is shown in FIGS. 1 to 6, and a wheel speed sensor P of this embodiment is similar to the wheel speed sensor P shown in FIGS. A lead piece 12 as a lead terminal is led out in parallel from the lead piece 12, and an electronic component 13 such as a capacitor is provided between the two lead pieces 12 and 12, but the lead piece 12 extends linearly from the Hall IC 11. It is. In addition, the same code | symbol as the above-mentioned shows the same thing.

  As shown in FIGS. 3 to 7, the resin molded product holder 20 has a fitting recess 14 for the Hall IC 11 formed in the front portion of one surface of the rectangular parallelepiped. Locking claws 15 that fit onto the surface of the Hall IC 11 are provided on both sides of the Hall IC fitting recess 14, and when the Hall IC 11 is fitted into the recess 14 from the front as shown in FIG. 5), the locking claw 15 is locked to the side protrusion 11a of the Hall IC 11 (see FIG. 4).

  An insertion hole 16 for the lead piece 12 is formed in the rear wall of the holder 20 (see FIGS. 1 and 5), and the lead piece 12 is inserted into the insertion hole 16 and the hole IC 11 is locked. Due to the locking by the claw 15, the detection part a is reliably positioned and set (held) on the holder 20. In the figure, reference numeral 8 denotes a locking tool that fits the holder 20 after the detection part a is set in the holder 20, and when the locking tool 8 fits in the holder 20, the detection part a is securely attached to the holder 20. Hold.

  The connecting portions 9, 9 between the lead piece 12 of the holder 20 and the pair of flexible core wires 6a of the output cable 6 are provided with a partition wall 22 positioned between them to prevent contact between the core wires 6a, 6a. A notch 23 is provided on the surface of the partition wall 22 facing the connection portions 9 and 9 so that the fillet of the soldering c connecting the lead piece 12 and the core wire 6a can be easily seen. The depth of the notch 23 (in the left-right direction in FIG. 8) is appropriately selected in consideration of the degree that the fillet of the soldering c can be easily seen. At this time, as long as the contact of the core wires 6a and 6a is prevented, both the notches 23 and 23 can be connected (the partition wall 22 is penetrated).

Further, the holder 20 in contact with the back surface of the lead piece 12 of both the connecting portions 9 and 9 is provided with a recess 24 for preventing escape of heat when the connecting portions 9 and 9 are soldered. As shown in FIG. 3, the recess 24 does not need to penetrate vertically, and as long as there is no hindrance to the support of the lead piece 12 on the surface of the holder 20 in contact with the lead piece 12, What is necessary is just to provide a hollow so that it may not contact | connect.

  Further, side walls 25 that prevent the flexible core wire 6a from moving to the outside are provided on both sides of the connecting portions 9 and 9 of the holder 20. The side wall 25 forms a pocket portion (a space surrounded by the side wall 25 and the partition wall 22) 25a, and when the cores 6a and 6a of the output cable 6 are set on the lead pieces 12 and 12, the pocket portion 25a The exposed core wires 6a and 6a at the end of the output cable 6 are inserted and positioned, and then the core wires 6a and 6a are placed along the partition wall 22 with the partition wall 22 interposed therebetween. At that time, as the core wires 6a, 6a are inserted into the pocket portions 25a, the core wires 6a, 6a are brought closer to the partition wall 22 side by the inclined surface 26a of the projection 26 on the inner side surface of the side wall 25 and are surely along the partition wall 22 (see FIG. 7), the lead terminal 12 and the core wire 6a are positioned on the same axis.

As shown in FIG. 8A, the flexible core wire 6a is connected to the lead piece 12 by soldering c to the holder 20 with the detecting portion a by a soldering iron C. During the soldering c,
Since the lead terminal 12 and the core wire 6a are positioned on the same axis, the bonding between the two terminals 12 and 6a is ensured, and the recess 24 prevents diffusion of solder heat as shown in FIG. As a result, smooth soldering is performed. Further, as shown in FIG. 7B, the notch 23 makes it easy to see the fillet of the soldering c, so that it is easy to judge whether the soldering is good or bad. Further, the solder c enters the notch 23, so that the bonding strength between the core wire 6a and the lead terminal 12 is also improved.

After the flexible core wire 6a is connected to the lead piece 12, the Hall IC 11, the lead piece 12, the entire holder 20, the output cable 6 and a part of the mounting bracket 10 are embedded, and the resin coating 4 is applied to the rotation detection sensor. Get P.
During the resin molding, the side wall 25 prevents the flexible core wire 6a from moving outward. At this time, it is preferable to twist the entire flexible core wire 6a so as to eliminate the unraveling.

  Moreover, as shown in FIG. 2, the positioning rib e when attaching the wheel speed sensor P is set to a position different from the parting line T of the mold. Thus, the positioning rib e is not obscured by the burr of the parting line T. Therefore, as shown in FIG. 1, the wheel speed sensor P is inserted into the hole D of the mounting member A, and the fixing bracket 10 is attached. When screwing, the wheel speed sensor P can be attached to a predetermined accurate position with the positioning rib e.

  As shown in FIG. 9, the detection part a is attached to the holder 20 even when the lead piece 12 has a U-shape. The part a can be prevented from being lifted up. The partition wall 22, the notch 23, the recess 24, the side wall 25, and the protrusion 26 can be appropriately omitted as long as there is no hindrance.

  Although the embodiment is a wheel speed sensor, it is needless to say that the present invention can be applied to other rotation detection sensors.

Main part cutting front view of one embodiment XX sectional view of FIG. The perspective view of the principal part of the Example XX sectional view of FIG. The exploded perspective view of the principal part of the example Perspective view from below of holder of same embodiment (A) is a bottom view of the holder, (b) is a right side view of (a). Operational diagram of this embodiment Cutaway front view of the main part of the conventional example The exploded perspective view of the detection part of the conventional example

Explanation of symbols

2, 20 Holder 4 Resin coating 6 Output cable 11 Hall IC (rotation detector)
12 Lead piece (Lead terminal)
14 Hall IC fitting recessed part 15 Claw 22 Bulkhead 23 Notch 24 Recessed part 25 Side wall 26 Protrusion 26a Inclined surface a Detection part e Positioning rib A Mounting member B Detected object C Soldering iron D Rotation detection sensor mounting hole T Gold Type parting line P Wheel speed sensor (rotation detection sensor)

Claims (4)

A rotation detecting element (11) that detects a magnetic field variation due to rotation of the detection object (B) and converts it into an electric signal, a holder (20) to which the rotation detecting element (11) is attached, and the holder (20) A recess (14) into which the formed rotation detection element (11) is fitted, and a lock formed on the rotation detection element (11) formed in the recess (14) to lift the rotation detection element (11). A latching claw (15) to be prevented and an output drawn out of the holder (20) from the rotation detection element (11) through a pair of lead terminals (12, 12) of the rotation detection element (11) The cable (6) and the rotation detection element (11), the lead terminal (12), the holder (20) and the resin coating (4) in which a part of the output cable (6) is embedded ,
The holder (20) is positioned between the connecting portions (9, 9) between the pair of lead terminals (12, 12) and the core wires (6a, 6a) of the output cable (6). A partition wall (22) for preventing contact between both core wires (6a, 6a) is provided, and the connection portion (22) is connected to the holder (20) in contact with the back surface of the lead terminal (12) of the connection portions (9, 9). 9,9) soldering (c) set a recess (24, 24) for preventing the escape of heat at the time of only, the surface facing to the two connection portions (9, 9) of the partition (22), the A rotation detection sensor comprising notches (23, 23) for making a soldered fillet easy to see. A rotation detecting element (11) that detects a magnetic field variation due to rotation of the detection object (B) and converts it into an electric signal, a holder (20) to which the rotation detecting element (11) is attached, and the holder (20) A recess (14) into which the formed rotation detection element (11) is fitted, and a lock formed on the rotation detection element (11) formed in the recess (14) to lift the rotation detection element (11). A latching claw (15) to be prevented and an output drawn out of the holder (20) from the rotation detection element (11) through a pair of lead terminals (12, 12) of the rotation detection element (11) The cable (6) and the rotation detection element (11), the lead terminal (12), the holder (20) and the resin coating (4) in which a part of the output cable (6) is embedded ,
The holder (20) is positioned between the connecting portions (9, 9) between the pair of lead terminals (12, 12) and the core wires (6a, 6a) of the output cable (6). A partition wall (22) for preventing contact between both core wires (6a, 6a) is provided, and the holder (20) is provided on both sides of the connection portions (9, 9) on the outside of the core wires (6a, 6a). setting the wall (25, 25) to prevent the movement of,
A protrusion (26) is provided on the inner surface of the wall (25, 25), and the surface of the protrusion (26) on the partition wall (22) side is a pocket between the wall (25, 25) and the partition wall (22). It becomes the inclined surface (26a) which approaches the partition (22) toward the inside of the part (25a), and as the core wire (6a, 6a) is inserted into the pocket part (25a), the protrusion (26) A rotation detection sensor characterized in that the core wire (6a, 6a) is brought closer to the partition wall (22) side by the inclined surface (26a) and is surely along the partition wall (22). A rotation detecting element (11) that detects a magnetic field variation due to rotation of the detection object (B) and converts it into an electric signal, a holder (20) to which the rotation detecting element (11) is attached, and the holder (20) A recess (14) into which the formed rotation detection element (11) is fitted, and a lock formed on the rotation detection element (11) formed in the recess (14) to lift the rotation detection element (11). A latching claw (15) to be prevented and an output drawn out of the holder (20) from the rotation detection element (11) through a pair of lead terminals (12, 12) of the rotation detection element (11) The cable (6) and the rotation detection element (11), the lead terminal (12), the holder (20) and the resin coating (4) in which a part of the output cable (6) is embedded ,
The holder (20) is positioned between the connecting portions (9, 9) between the pair of lead terminals (12, 12) and the core wires (6a, 6a) of the output cable (6). A partition wall (22) for preventing contact between both core wires (6a, 6a) is provided, and the connection portion (22) is connected to the holder (20) in contact with the back surface of the lead terminal (12) of the connection portions (9, 9). set a recess (24, 24) for preventing the escape of heat during the 9,9) is soldered (c),
In the holder (20), set the walls (25, 25) to prevent outward movement of said core on both sides (6a, 6a) of both connecting portions (9,9),
A protrusion (26) is provided on the inner surface of the wall (25, 25), and the surface of the protrusion (26) on the partition wall (22) side is a pocket between the wall (25, 25) and the partition wall (22). It becomes the inclined surface (26a) which approaches the partition (22) toward the inside of the part (25a), and as the core wire (6a, 6a) is inserted into the pocket part (25a), the protrusion (26) A rotation detection sensor characterized in that the core wire (6a, 6a) is brought closer to the partition wall (22) side by the inclined surface (26a) and is surely along the partition wall (22). In the holder (20), the said core (6a, 6a) on both sides of both connection portions (9,9) only set the walls (25, 25) to prevent outward movement of, its walls (25, 25 The projection (26) is provided on the inner surface of the projection (26), and the surface of the projection (26) on the partition (22) side is the inside of the pocket (25a) between the wall (25, 25) and the partition (22). It becomes an inclined surface (26a) that approaches the partition wall (22) toward the surface, and as the core wires (6a, 6a) are inserted into the pocket portion (25a), the inclined surface (26a) of the protrusion (26). The rotation detection sensor according to claim 1, wherein the core wires (6a, 6a) are brought close to the partition wall (22) so as to be surely along the partition wall (22).

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