CN1831538A

CN1831538A - Sensor for detecting rotary speed

Info

Publication number: CN1831538A
Application number: CNA2005100771471A
Authority: CN
Inventors: 姜声南; 金雄烈; 高长铉
Original assignee: Honeywell Inc
Current assignee: Sensata Technologies Inc
Priority date: 2005-03-11
Filing date: 2005-06-14
Publication date: 2006-09-13
Anticipated expiration: 2025-06-14
Also published as: CN100419432C; KR100624331B1

Abstract

The present invention discloses one kind of rotation speed detecting sensor capable of raising the reliability of product, simplifying production process and lowering production cost. The rotation speed detecting sensor includes one winding assembly with reel and coil around the reel; one magnet set near the coil for inducing electromotive force in the coil by means of magnetic field change of the relatively rotating phonic wheel; one sealing coating injected to the outer surface of the winding assembly to protect its outer surface; and one casing outside the sealing coating.

Description

Be used to detect the sensor of rotating speed

Technical field

The present invention relates to a kind of sensor that is used to detect rotating speed, relate more specifically to a kind of like this sensor that is used to detect rotating speed, it can improve product reliability, and simplified manufacturing technique also reduces production costs.

Background technology

If when the driver steps on brake suddenly or when he steps on when braking and make wheel locking, then uncontrollable vehicle on abominable road surface.The ABS system limits the generation of accident by preventing locked and keeping best sliding mode.

For example, can will be installed on the wheel bearing of vehicle variable reluctance (VR) sensor application as monomer in the ABS system.

Auto maker uses the VR sensor that combines with bearing that packaging technology is simplified and modularization.Therefore, be widely adopted by 3G (generation) bearing of realizing miniaturization that will combine with wheel bearing such as the related elements of sensor.

Figure 1A to 1G is a synoptic diagram, shows the traditional VR sensor 100a that combines with the 3G bearing.

Traditional VR sensor 100a comprises housing 10a, bobbin 20a, coil 30a, magnet 50a, terminal and cable 60a, and the rotating speed of the phonic wheel 200 of electrical signal form is detected.

Figure 1A is the schematic cross sectional views that shows the housing 10a of traditional VR sensor 100a.

This housing 10a is formed on the external position of sensor 100a, be used to stop the external magnetic field and the magnetic field that prevents to produce by magnet 50a to external leakage.Be pasted with dynamic sealing on this housing 10a, be used to keep sealing state, be penetrated among the sensor 100a and bearing that assembles to prevent water or exterior materials.

Figure 1B is the schematic perspective view that shows bobbin 20a.

Bobbin 20a is the basic structure that coil 30a and magnet 50a are installed on it.

Fig. 1 C is the schematic perspective view that shows winding assembly 40a.

Coil 30a is wrapped in around the excircle of bobbin 20a.Winding assembly 40a comprises bobbin 20a and is wrapped in this bobbin 20a coil 30a on every side.

Fig. 1 D is the schematic perspective view that shows magnet 50a.

Magnet 50a produces magnetic field with phonic wheel 200.Magnet 50a forms the ring-type with preset width and thickness.The N utmost point and the S utmost point alternately are formed on the inner periphery of magnet 50a.

Fig. 1 E is the schematic cross sectional views that shows the sensor 100a be used to detect rotating speed.

Shown in Fig. 1 E, the sensor 100a that is used to detect rotating speed comprises the housing 10a of Figure 1A, the winding assembly 40a of Fig. 1 C, and the magnet 50a of Fig. 1 D.

Coil 30a is wrapped in around the field region of magnet 50a and phonic wheel 200, is used for changing changes of magnetic field into electric signal.

Fig. 1 F is the schematic perspective view that shows phonic wheel 200.

Phonic wheel 200 produces magnetic field with magnet 50a.Phonic wheel 200 forms ring-type.On the excircle of phonic wheel 200, be formed with a plurality of teeth with predetermined space.The quantity of tooth and the quantity that is formed on the magnetic pole on the inner periphery of magnet 50a, that is, the quantity of the N utmost point and the S utmost point equates.Phonic wheel 200 is made by magnetic material.

Fig. 1 G is a schematic cross sectional views, demonstrates to be used to detect the sensor 100a of rotating speed and the engagement state between the phonic wheel 200.

Shown in Fig. 1 G, phonic wheel 200 is installed in the inside of bobbin 20a, has formed the circle concentric with magnet 50a.

When phonic wheel 200 rotations, the N utmost point of the tooth of phonic wheel 200 and magnet 50a and the distance between the S utmost point change, and therefore by this phonic wheel 200 and the formed change of flux of magnet 50a, thereby induce electromotive force for coil 30a.

When the rotating speed of phonic wheel 200 changed, the variation rate of magnetic flux in magnetic field also changed, thereby changed for the electromotive force amount that coil 30a induces.Induction electromotive force outwards transmits by cable 60a and is resolved.That is, as shown in Figure 2, the rotating speed that detects phonic wheel 200 with the form of voltage and frequency is as electric signal, and sends the ECU as controller of vehicle to.

Yet the traditional sensors 100a that is used to detect rotating speed has following shortcoming.The hermetically-sealed construction that is used to detect the sensor 100a of rotating speed is that the dynamic sealing by poor sealing performance forms.Therefore, because poor sealing performance may cause water or exterior materials to be penetrated among the sensor 100a.When water or exterior materials were penetrated among the sensor 100a, sensor 100a just can't operate as normal, and its life-span also can seriously shorten.Therefore, since more emat sensor 100a can cause extra expense.

Summary of the invention

For overcoming the above problems the present invention is proposed.An object of the present invention is to provide a kind of sensor that is used to detect rotating speed, this sensor replaces with new structure by the dynamic seal (packing) structure that will stick on the housing, and can keep excellent sealing performance.

Another object of the present invention provides a kind of sensor that is used to detect rotating speed, and it can simplified manufacturing technique and reduces production costs.

In order to realize above-mentioned purpose of the present invention, a kind of sensor that is used to detect rotating speed is provided, it comprises: winding assembly, it has bobbin and is wrapped in this bobbin coil on every side; Be arranged near the magnet the coil, be used for by phonic wheel produces changes of magnetic field with carrying out in relative rotation, thereby for the described coil-induced electromotive force that goes out; O-ring seal mouth (overmold), its as monomer and injection moulding on the outside surface of described winding assembly, be used for around with the protection described winding assembly outside surface; And housing, its outside at the O-ring seal mouth engages with the O-ring seal mouth.

Preferably, the sensor that is used to detect rotating speed comprises: be formed on the bobbin and the terminal that links to each other with coil; And the cable that links to each other with this terminal; be used for and outwards transmit at the induction electromotive force that described coil produces; the injection moulding of wherein said O-ring seal mouth is monomer, with around and protect coupling part between described coil, described coil and the described terminal and the coupling part between described terminal and the described cable.

Preferably, described magnet arrangement is in the lower end of the inner periphery of described bobbin, and described O-ring seal mouth as monomer injection moulding on the basal surface of this magnet, be used for supporting this magnet.

Preferably, be used to prevent that the rib of contact from stretching out from the bottom of sealing circle mouth downwards, thereby prevent to be used to detect the sensor of rotating speed owing to damaging with contacting excessively of bearing.

Description of drawings

With reference to the following drawings, the present invention may be better understood, and only the mode with example provides these accompanying drawings, so they are not to be used to limit the present invention, in the accompanying drawings:

Figure 1A to 1G is the synoptic diagram that shows the traditional sensors be used to detect rotating speed, wherein:

Figure 1A is the schematic cross sectional views that shows housing;

Figure 1B is the schematic perspective view that shows bobbin;

Fig. 1 C is the schematic perspective view that shows winding assembly;

Fig. 1 D is the schematic perspective view that shows magnet;

Fig. 1 E is the schematic cross sectional views that shows the traditional sensors be used to detect rotating speed;

Fig. 1 F is the schematic perspective view that shows phonic wheel; And

Fig. 1 G is a schematic cross sectional views, demonstrates to be used to detect the sensor of rotating speed and the engagement state of phonic wheel;

Fig. 2 is the curve map of output valve of traditional sensors that is used to detect rotating speed that demonstrates Fig. 1 G;

Fig. 3 A to 3H is a synoptic diagram, demonstrates the sensor that is used to detect rotating speed according to first embodiment of the invention, wherein:

Fig. 3 A is the schematic perspective view that shows housing;

Fig. 3 B is the schematic perspective view that shows bobbin;

Fig. 3 C is the schematic perspective view that shows winding assembly;

Fig. 3 D is the schematic perspective view that shows magnet;

Fig. 3 E is the schematic perspective view that shows the O-ring seal mouth, and sealing circle mouth has been equipped with thereon as monomer injection moulding on the outside surface of winding assembly of magnet;

Fig. 3 F is the schematic perspective view that shows the sensor be used to detect rotating speed;

Fig. 3 G is the schematic perspective view that shows phonic wheel; And

Fig. 3 H schematically analyses and observe, and demonstrates to be used to detect the sensor of rotating speed and the engagement state of phonic wheel;

Fig. 4 is the curve map of output valve of sensor that is used to detect rotating speed of displayed map 3H; And

Fig. 5 A to 5C is a synoptic diagram, demonstrates the sensor that is used to detect rotating speed according to second embodiment of the invention, wherein:

Fig. 5 A is the schematic perspective view that shows housing;

Fig. 5 B is a schematic perspective view, demonstrates as monomer injection moulding O-ring seal mouth on the outside surface of winding assembly of magnet has been installed thereon; And

Fig. 5 C is the schematic perspective view that shows the sensor be used to detect rotating speed.

Embodiment

Describe the sensor that is used to detect rotating speed according to of the present invention below with reference to accompanying drawings in detail.

Fig. 3 A to 3H is a synoptic diagram, demonstrates the sensor 100b that is used to detect rotating speed according to first embodiment of the invention.Fig. 3 A is the schematic perspective view that shows housing 10b.

Housing 10b is formed on the external position of this sensor 100b, be used for stopping the external magnetic field and the magnetic field that prevents to produce by magnet 50b to external leakage.This housing 10b is simplifying in shape more than the housing 10a of Figure 1A.

Fig. 3 B is the schematic perspective view that shows bobbin 20b.

Bobbin 20b is the basic structure that coil 30b and magnet 50b are installed on it.Terminal stretches out from bobbin 20b.

Fig. 3 C is the schematic perspective view that shows winding assembly 40b.

Coil 30b is wrapped in around the excircle of bobbin 20b.Winding assembly 40b comprises bobbin 20b and is wrapped in this bobbin 20b coil 30b on every side.

Fig. 3 D is the schematic perspective view that shows magnet 50a.

Magnet 50b produces magnetic field with phonic wheel 200.Magnet 50b forms the ring-type with preset width and thickness.The N utmost point and the S utmost point alternately are formed on the inner periphery of magnet 50b.

Fig. 3 E is schematic solid, demonstrates as monomer injection moulding O-ring seal mouth 70b on the winding assembly 40b outside surface of magnet 50b has been installed thereon.

O-ring seal mouth 70b is by the dynamic sealing of the housing 10a of replacement Figure 1A, with the inner member of sealing and protection sensor 100b.O-ring seal mouth 70b as monomer injection moulding on the outside surface of winding assembly 40b, with around with the outside surface of protection winding assembly 40b.Particularly, O-ring seal mouth 70b injection moulding is used to protect them on the coupling part between the coupling part between coil 30b, coil 30 and the terminal and terminal and the cable 60b.

With reference to Fig. 3 E, O-ring seal mouth 70b is used for supporting this magnet 50b as monomer injection moulding on the basal surface of magnet 50b, and this magnet 50b is installed in the lower end of the inner periphery of bobbin 20b.Therefore, can simplify the mounting process of magnet 50b.

Fig. 3 F is the schematic perspective view that shows the sensor 100b be used to detect rotating speed.

Shown in Fig. 3 F, the sensor 100b that is used to detect rotating speed comprises housing 10b, bobbin 20b, terminal, coil 30b, magnet 50b, O-ring seal mouth 70b and cable 60b.

Coil 30b is wrapped in the field region place of magnet 50b and phonic wheel 200, is used for changing changes of magnetic field into electric signal.Therefore, coil 30b and magnet 50 are adjacent to twine.In addition, coil 30b is connected to described terminal.

Cable 60b is connected to described terminal, and the induction electromotive force that is used for producing at coil 30b outwards transmits.

Below packaging technology will be described simply.Coil 30b is wrapped in around the excircle of bobbin 20b, magnet 50b places on the inner periphery of bobbin 20b, and O-ring seal mouth 70b injection moulding becomes monomer, and housing 10b is bonded on the resulting structures.

Fig. 3 G is the schematic perspective view that shows phonic wheel 200.

Phonic wheel 200 produces magnetic field with magnet 50b.Phonic wheel 200 forms ring-type.On the excircle of phonic wheel 200, be formed with a plurality of teeth with predetermined space.The quantity of tooth and the quantity that is formed on the magnetic pole on the inner periphery of magnet 50b, promptly the quantity of the N utmost point and the S utmost point equates.Phonic wheel 200 is made by magnetic material.

Fig. 3 H is a schematic cross sectional views, demonstrates to be used to detect the sensor 100b of rotating speed and the engagement state between the phonic wheel 200.

Shown in Fig. 3 H, phonic wheel 200 is installed in the inside of bobbin 20b, to form the circle concentric with magnet 50b.

When phonic wheel 200 rotation, the N utmost point of the tooth of phonic wheel 200 and magnet 50b and the distance between the S utmost point change, so the change of flux that is formed by this phonic wheel 200 and magnet 50b, thereby induce electromotive force for coil 30b.

When the rotating speed of phonic wheel 200 changed, the variation rate of magnetic flux in magnetic field also changed, so the induction electromotive force amount changes.Induction electromotive force outwards transmits by cable 60b and is resolved.That is, as shown in Figure 4, the rotating speed that detects phonic wheel 200 with the form of voltage and frequency is as electric signal, and sends the ECU as controller of vehicle to.

Sensor of the present invention is suitable for being installed on the bearing as monomer, and is specially adapted to the ABS system of vehicle.

Fig. 5 A to 5C is a synoptic diagram, demonstrates the sensor 100c that is used to detect rotating speed according to second embodiment of the invention.Fig. 5 A is the schematic perspective view that shows housing 10c.

Shown in Fig. 5 A, can revise the shape of housing 10c according to bearing.

Fig. 5 B is a schematic perspective view, demonstrates as monomer injection moulding O-ring seal mouth 70c on the outside surface of winding assembly of magnet has been installed thereon.

Shown in Fig. 5 B, be formed with rib 80 at the place, bottom of O-ring seal mouth 70c, damage in order to the sensor 100c that prevents to be installed on the bearing.In the sensor construction of Fig. 3 H, sensor 100b may damage owing to the mistake assembling of bearing and sensor 100b.Particularly, because it is frangible to be arranged in the magnet 50b of lower end, so be easy to break owing to for example excessive insertion of carelessness produces.Therefore, be used to prevent that the rib 80b of contact from stretching out from the bottom of O-ring seal mouth 70c downwards, thereby prevent to be used to detect the sensor 100c of rotating speed owing to damaging with contacting excessively of bearing.

Fig. 5 C is the schematic perspective view that shows the sensor 100c be used to detect rotating speed.

Shown in Fig. 5 C, can revise the sensor 100c that is used to detect rotating speed according to the shape of connector that is used for this sensor 100c is connected to the ECU of vehicle.

As mentioned above; according to the present invention; the sensor that is used to detect rotating speed has very high reliability by improving sealing property; this can be by removing traditional dynamic sealing; and be provided for protecting the novel sealing structure of inner member (for example, coil and cable) to realize by injection molding technique.As a result, the cost that has reduced consumer's claim and produced thereupon.

In addition, reduced component costs by removing described dynamic sealing, and improved throughput rate by simplified assembling process.

Although preferred embodiments of the present invention have been disclosed for illustrative; but should be appreciated that; the present invention should not be limited to these preferred embodiments; to those skilled in the art; can in the spirit and scope of claims the present invention for required protection, the present invention be made various changes and modifications.

Claims

1, a kind of sensor that is used to detect rotating speed comprises:

Winding assembly, it has bobbin and is wrapped in this bobbin coil on every side;

Be arranged near the magnet the described coil, be used for by phonic wheel produces changes of magnetic field with carrying out in relative rotation, thereby for the described coil-induced electromotive force that goes out;

The O-ring seal mouth, its as monomer injection moulding on the outside surface of described winding assembly, be used for around with the protection described winding assembly outside surface; And

Housing, its outside at described O-ring seal mouth engages with sealing circle mouth.

2, sensor according to claim 1 is characterized in that, comprising:

Terminal, it is formed on the described bobbin and with described coil and links to each other; And

With the cable that this terminal links to each other, the induction electromotive force that is used for producing at described coil outwards transmits,

Wherein, the injection moulding of described O-ring seal mouth is monomer, with around and protect coupling part between described coil, described coil and the described terminal and the coupling part between described terminal and the described cable.

3, sensor according to claim 2 is characterized in that, described magnet arrangement is in the lower end of the inner periphery of described bobbin, and described O-ring seal mouth as monomer injection moulding on the basal surface of described magnet, be used for supporting this magnet.

4, according to each described sensor in the claim 1 to 3, it is characterized in that, be used to prevent that the rib of contact from stretching out from the bottom of described O-ring seal mouth downwards, in order to prevent being used to detect the described sensor of rotating speed owing to damaging with contacting excessively of bearing.