Resolver equipped with speed detection function

Abstract

To provide a resolver equipped with a function of speed detection without being large-sized in the radial direction.SOLUTION: A resolver comprises: a resolver unit 100 having a rotating shaft 110 for outputting a signal corresponding to the angle of the rotating shaft 110; and a speed sensor unit 200 having a gear 210 rotating together with the rotating shaft 110 and at least one detection unit 220 for outputting a speed signal corresponding to the rotation of the gear 210. The gear 210 comprises at least one tooth 212 at the end of a disc 211. The detection unit 220 comprises a core 221 around which a detection wire 225 is wound, a first core end part 222 of the core 221, and a magnet 226 contacting a second core end part 224 of the core 221. The first core end part 222 is arranged so as to face the tooth 212, and also arranged so that the direction along the shaft center of the core 221 is parallel to the axial direction of the rotating shaft 110.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a resolver having a speed detection function. [Background technology]

[0002] A resolver is an angle sensor that outputs a two-phase AC signal according to the rotation angle as a resolver signal. Since resolvers are composed only of an iron core and a coil, they are resistant to external vibrations and shocks and have a structurally higher environmental resistance than other sensors.

[0003] On the other hand, although a resolver can detect angles, it cannot detect speed. Therefore, to detect speed, it is necessary to either add a processing circuit that processes the resolver signal to calculate the speed, or to mechanically add a speed sensor to the resolver. In other words, it is necessary to improve the processing circuit or the sensor itself, and in either case, there is a problem that the configuration becomes complicated. This type of resolver is described in Patent Document 1. Also, a speed sensor that can be added to a resolver is described in Patent Document 2. This speed sensor is composed of a core, a coil, and a magnet, does not require an external power supply, is resistant to vibration, impact, and noise, and has a structurally high environmental resistance. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2008-259355 A [Patent Document 2] JP 2000-65845 A Summary of the Invention [Problem to be solved by the invention]

[0005] When mechanically adding a speed sensor to a resolver, in the resolver described in Patent Document 1, it is necessary to provide a gear on the rotating shaft and attach the speed sensor described in Patent Document 2 to the radially outer side of the gear. In this case, adding a speed sensor unit as in Patent Document 2 to the resolver increases the size of the resolver in the radial direction. This poses a problem that it is difficult to attach the resolver to various devices. That is, it has been desired to provide a resolver with a speed detection function without increasing the size in the radial direction by adding a speed sensor to the resolver.

[0006] The present invention has been made to solve the above problems, and has an object to provide a resolver that has a speed detection function without increasing its size in the radial direction. [Means for solving the problem]

[0007] The resolver with speed detection function of the present invention comprises a resolver unit having a rotating shaft and outputting a signal corresponding to the angle of the rotating shaft, and a speed sensor unit having a gear rotating together with the rotating shaft and at least one detection unit and outputting a speed signal corresponding to the rotation of the gear, the gear having at least one tooth at the end of the disk, the detection unit comprising a core wound with a detection winding, a first core end of the core, and a magnet in contact with the second core end of the core, the first core end being arranged opposite the teeth and arranged so that the direction along the axis of the core is parallel to the axial direction of the rotating shaft.

[0008] In the resolver with speed detection function according to the present invention, the teeth are configured to protrude in the axial direction toward the first core end.

[0009] In the resolver with a speed detection function according to the present invention, the gear has teeth on a first surface of a disk, and an auxiliary magnet is provided on a second surface of the disk.

[0010] In the resolver with a speed detection function according to the present invention, a plurality of detection sections are provided, and the plurality of detection sections are arranged so as to have different phases with respect to the teeth.

[0011] In the resolver with speed detection function according to the present invention, a magnetic pole tip having a cross section smaller in diameter than the cross section of the core and determined according to the thickness of the teeth is further provided at the first core end so as to face the teeth.

[0012] In the resolver with speed detection function of the present invention, the resolver unit includes a rotor that can rotate together with a rotating shaft and a cylindrical stator that is fixedly attached to the periphery of the rotor, the speed sensor unit is configured so as not to exceed the outer diameter of the stator, and the resolver unit and the speed sensor unit are housed in a cylindrical case. Effect of the Invention

[0013] According to the present invention, it is possible to provide the resolver with a speed detection function without increasing its size in the radial direction. [Brief description of the drawings]

[0014] [Figure 1] 1 is a cross-sectional view showing a configuration of a resolver having a speed detection function according to a first embodiment. [Diagram 2] FIG. 2 is a cross-sectional view showing the II-II cross section of FIG. [Diagram 3] 1 is a perspective view showing a schematic configuration inside a case of a resolver having a speed detection function according to a first embodiment. FIG. [Figure 4] 10 is a perspective view showing a schematic configuration inside a case of a resolver having a speed detection function according to a second embodiment. FIG. [Diagram 5] FIG. 11 is a perspective view showing a schematic configuration inside a case of a resolver having a speed detection function according to a third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, an embodiment of a resolver 1 having a speed detection function according to the present invention will be described with reference to the drawings. In each drawing, the same parts are denoted by the same reference numerals.

[0016] Embodiment 1 First, the basic configuration of a resolver 1 with a speed detection function in the first embodiment will be described with reference to Figs. 1 to 3. Fig. 1 is a cross-sectional view showing the configuration of the resolver 1 with a speed detection function according to the first embodiment. Fig. 2 is a cross-sectional view showing a cross section taken along line II-II in Fig. 1. Fig. 3 is a perspective view showing a schematic configuration inside a case of the resolver 1 with a speed detection function according to the first embodiment.

[0017] The resolver 1 having a speed detection function mainly includes a case 10, a resolver unit 100, and a speed sensor unit 200. The case 10 is formed in a cylindrical shape, and houses the resolver unit 100 and the speed sensor unit 200 therein.

[0018] First, a description will be given of the resolver unit 100. The resolver unit 100 includes a rotating shaft 110, a transformer unit 120, a rotor 130, and a stator 140. Note that descriptions of known members of the resolver unit 100, such as bearings, holding members, and fillers, will be omitted.

[0019] The rotating shaft 110 is connected to a measurement object (not shown) and rotates together with the measurement object. The rotating shaft 110 is provided so as to pass through the resolver unit 100 and extend toward the speed sensor unit 200. The rotating shaft 110 may be a hollow shaft other than the solid shaft shown in FIG.

[0020] The transformer unit 120 includes a stator transformer unit 121 and a rotor transformer unit 122. The stator transformer unit 121 is configured to be fixed within the resolver unit 100. The rotor transformer unit 122 is configured to be rotatable together with the rotating shaft 110. Power supplied from the outside is supplied in a non-contact state from the stator transformer unit 121 to the rotor transformer unit 122, which rotates together with the rotating shaft 110, by electromagnetic induction.

[0021] The rotor 130 is provided with a rotor core 131 and a rotor coil 132. The rotor coil 132 is wound around the rotor core 131. The rotor 130 is configured to be rotatable together with the rotating shaft 110. The rotor coil 132 receives power from the rotor transformer unit 122 and acts as an excitation winding. In other words, the rotor 130 rotates together with the rotating shaft 110, and the rotor coil 132 generates a rotating excitation magnetic field.

[0022] The stator 140 includes a stator core 141 and a stator coil 142. The stator 140 is configured in a fixed state within the resolver unit 100. The stator coil 142 is wound around the stator core 141. The stator coil 142 receives a rotating excitation magnetic field corresponding to the rotation of the rotor 130, and acts as a detection winding. The stator 140 supplies a voltage generated in the stator coil 142 to an external processing circuit (not shown) as a resolver signal.

[0023] Next, the speed sensor unit 200 will be described. The speed sensor unit 200 is provided with a gear 210 and at least one detection unit 220. The speed sensor unit 200 outputs a speed signal according to the rotation of the gear 210 to the outside. In Figs. 1 to 3, a state in which two detection units 220a and 220b are provided is shown.

[0024] Gear 210 is provided with a disk 211 and teeth 212. Disk 211 is provided on the end of rotating shaft 110 and configured to be rotatable together with rotating shaft 110. Teeth 212 are configured from at least one protruding piece of a magnetic material on the end of disk 211. In the example shown in FIG. 3, the teeth 212 are configured with 10 equally spaced protruding pieces, making the number of teeth 10. By increasing the number of teeth, the resolution of detecting the rotation speed can be improved. The protruding pieces constituting the teeth 212 are not limited to the rectangular shape shown in the figure, but may be any of trapezoidal, triangular, semicircular, sinusoidal, cylindrical or prismatic pins. The teeth 212 are arranged so as to protrude from the disk 211 in parallel with the axial direction of the rotating shaft 110 and toward the first core end 222 of the detection unit 220.

[0025] The detection unit 220 mainly has a core 221, a detection winding 225, and a magnet 226. The core 221 is made of a cylindrical magnetic material. The core 221 is arranged so that the direction along the axis of the core 221 is parallel to the axial direction of the rotating shaft 110. The detection winding 225 is wound around the core 221. A speed signal generated in the detection winding 225 when the gear 210 rotates is output to the outside. A first core end 222 which is one end of the core 221 is disposed so as to face the teeth 212. The magnet 226 is disposed so as to be in contact with a second core end 224 which is the other end of the core 221. Since the diameter of core 221 is larger than the thickness of tooth 212, magnetic pole tip 223 having a smaller diameter than the cross section of core 221 and a cross section determined according to the thickness of tooth 212 is further provided on first core end 222 so as to face tooth 212. Note that instead of providing magnetic pole tip 223, first core end 222 may be machined to have a smaller diameter to match the thickness of tooth 212. This enables speed sensor unit 200 to efficiently detect the presence or absence of tooth 212 according to rotation.

[0026] With the above configuration, the detection unit 220 acts as a generator in response to the rotation of the gear 210. As a result, the speed sensor unit 200 does not require an external power supply, and outputs an AC signal corresponding to the rotation speed of the rotating shaft 110 and the number of teeth of the gear 210 to the outside as a speed signal. Since the detection unit 220 acts as a generator and does not require an external power supply, it is sometimes called a "power-less sensor." Here, the detection unit 220 has a simple configuration consisting of a core 221, a detection winding 225, and a magnet 226, and since it is composed only of a core, a coil, and a magnet, it is resistant to external vibrations, impacts, and noise, and has a structurally higher environmental resistance than other speed sensors.

[0027] 2, the detection units 220a and 220b are arranged in a state where they are shifted in phase by 1 / 2 tooth with respect to the gear 210, that is, in a state where they are in different phases with respect to the tooth 212. Here, different phases with respect to the tooth 212 means that the timing from the start of approach to the end of approach of one protruding piece of the tooth 212 in the detection unit 220a and the timing from the start of approach to the end of approach of one protruding piece of the tooth 212 in the detection unit 220b do not completely match, but there is a shift. This makes it possible to analyze the speed signal in a signal processing circuit (not shown) and detect the rotation speed and rotation direction of the rotating shaft 110.

[0028] 1 and 3, a speed sensor unit 200 having a gear 210 and at least one detection unit 220 is configured so as not to exceed the outer diameter of a stator 140 of a resolver unit 100. The resolver unit 100 and the speed sensor unit 200 are housed in a cylindrical case 10. As a result, by adding the speed sensor unit 200 to the resolver unit 100 and housing it in a cylindrical case 10, it is possible to realize a resolver 1 with a speed detection function in a mechanically robust state without increasing the radial size.

[0029] The effects obtained by the first embodiment will be described below. The resolver 1 with the speed detection function described in the above embodiment 1 comprises a resolver unit 100 having a rotating shaft 110 and outputting a resolver signal according to the angle of the rotating shaft 110, and a speed sensor unit 200 having a gear 210 rotating together with the rotating shaft 110 and at least one detection unit 220 and outputting a speed signal according to the rotation of the gear 210, the gear 210 having at least one tooth 212 at an end of a disk 211, the detection unit 220 comprising a core 221 wound with a detection winding 225, a first core end 222 of the core 221, and a magnet 226 in contact with a second core end 224 of the core, the first core end 222 being arranged to face the tooth 212 and being arranged so that the direction along the axis of the core 221 is parallel to the axial direction of the rotating shaft 110. This makes it possible to realize a resolver 1 having a speed detection function by adding the speed sensor unit 200 to the resolver unit 100 without increasing the size in the radial direction.

[0030] In the resolver 1 having a speed detection function according to the above-described first embodiment, the teeth 212 are configured to protrude axially toward the first core end portion 222. As a result, when the speed sensor unit 200 is added to the resolver unit 100, the teeth 212 and the detection unit 220 can be arranged so as to be parallel to the axial direction of the rotating shaft 110, making it possible to realize a resolver 1 with a speed detection function without increasing the radial size.

[0031] In the resolver 1 having a speed detection function according to the above-described first embodiment, the multiple detection units 220 are arranged so as to have different phases with respect to the teeth 212. This makes it possible to detect not only the rotation speed of the rotating shaft 110 but also the rotation direction by analyzing the speed signal in a signal processing circuit (not shown).

[0032] In the resolver 1 with the speed detection function of the above-mentioned embodiment 1, a magnetic pole tip 223 having a cross-section that is smaller in diameter than the cross-section of the core 221 and determined in accordance with the thickness of the tooth 212 is further provided at the first core end 222 so as to face the tooth 212. This enables the speed sensor section 200 to efficiently detect the presence or absence of the teeth 212 in response to rotation.

[0033] In the resolver 1 having the speed detection function according to the above-described first embodiment, the resolver unit 100 includes a rotor 130 that can rotate together with the rotating shaft 110, and a cylindrical stator 140 that is fixedly provided around the rotor 130, and the speed sensor unit 200 is configured so as not to exceed the outer diameter of the stator 140, and the resolver unit 100 and the speed sensor unit 200 are housed in a cylindrical case 10. As a result, by adding the speed sensor unit 200 to the resolver unit 100 and housing it in a cylindrical case 10, it is possible to realize a resolver 1 with a speed detection function in a mechanically robust state without increasing the radial size.

[0034] Embodiment 2 A schematic configuration of a resolver 1 having a speed detection function in the second embodiment will be described with reference to Fig. 4. Fig. 4 is a perspective view showing a schematic configuration inside a case 10 of a resolver 1 having a speed detection function according to the second embodiment. In Fig. 4, the same parts as those in Figs. 1 to 3 are given the same reference numerals, so that duplicated explanations are omitted, and different parts will be mainly described.

[0035] Teeth 212 are provided on a first surface of the disk 211 of the gear 210 facing the detection unit 220. Meanwhile, an auxiliary magnet 213 is provided on a second surface 211b of the disk 211. The auxiliary magnet 213 may be not only a ring-shaped magnet as shown in FIG. 4, but also a disk-shaped magnet that covers the entire second surface 211b of the disk 211 except for the portion that is connected to the rotating shaft 110, or a configuration in which magnets are individually disposed at positions corresponding to the respective protruding pieces that constitute the teeth 212.

[0036] The auxiliary magnet 213 in contact with the second surface 211b of the disk 211 has its polarities arranged so as to be opposed to each other in a manner that strengthens the magnetic flux flowing from the magnet 226 through the core 221 and the teeth 212. Specifically, when the polarity of the magnet 226 in contact with the second core end 224 is N pole, the magnetic pole tip 223 facing the tooth 212 is N pole, and the tooth 212 facing the magnetic pole tip 223 is S pole, so that the surface of the auxiliary magnet 213 in contact with the second surface 211b of the disk 211 is the S pole. Similarly, when the polarity of the magnet 226 in contact with the second core end portion 224 is an S pole, the surface of the auxiliary magnet 213 in contact with the second surface 211b of the disk 211 is set as an N pole.

[0037] With the above configuration, auxiliary magnet 213 can strengthen the magnetic flux flowing through core 221 and teeth 212. Therefore, the magnetic force of magnet 226 can be made weaker than in the first embodiment, and magnet 226 can be made smaller. Furthermore, by making magnet 226 smaller, detection unit 220 can be made smaller in the axial direction of rotation shaft 110. This makes it possible to realize a resolver 1 having a speed detection function by adding the speed sensor unit 200 to the resolver unit 100 without increasing the size in the radial direction and also without increasing the size in the axial direction.

[0038] The effects obtained by the second embodiment will be described below. In the resolver 1 with a speed detection function according to the above-described second embodiment, the gear 210 has teeth 212 provided on a first surface of the disk 211, and an auxiliary magnet 213 provided on a second surface 211b of the disk 211. In this configuration, the auxiliary magnet 213 can strengthen the magnetic flux flowing through the core 221 and the teeth 212. This allows the magnetic force of the magnet 226 to be weaker than that of the first embodiment, making it possible to reduce the size of the magnet 226. Furthermore, by reducing the size of the magnet 226, it becomes possible to reduce the size of the detection unit 220 in the axial direction of the rotation shaft 110. That is, by adding the speed sensor unit 200 to the resolver unit 100, it is possible to realize a resolver 1 having a speed detection function without increasing the size in the radial direction and also without increasing the size in the axial direction.

[0039] Embodiment 3 A schematic configuration of a resolver 1 having a speed detection function in a third embodiment will be described with reference to Fig. 5. Fig. 5 is a perspective view showing a schematic configuration inside a case 10 of a resolver 1 having a speed detection function according to a third embodiment. In Fig. 5, the same parts as those in Figs. 1 to 4 are given the same reference numerals, so that duplicated explanations are omitted, and different parts will be mainly described.

[0040] Gear 210 is provided with teeth 212 protruding radially outward from disk 211. First core end 222 or magnetic pole tip 223 is configured to face side surface 212a of teeth 212 that forms the same plane as first surface 211a of disk 211. The detection unit 220 acts as a generator depending on the presence or absence of protruding pieces that form the teeth 212 according to the rotation of the gear 210. As a result, the speed sensor unit 200 outputs an AC signal according to the rotation speed of the rotating shaft 110 and the number of teeth of the gear 210 to the outside as a speed signal.

[0041] With the above configuration, the teeth 212 protrude radially outward from the disk 211, and do not protrude from the disk 211 in a direction parallel to the axial direction of the rotating shaft 110. This makes it possible to reduce the size of the detection unit 220 in the axial direction of the rotating shaft 110. This makes it possible to realize a resolver 1 having a speed detection function by adding the speed sensor unit 200 to the resolver unit 100 without increasing the size in the radial direction and also without increasing the size in the axial direction. In this embodiment 3, it is possible to provide an auxiliary magnet 213 in the same manner as in embodiment 2. In this case, the magnet may be disposed on the surface opposite to the side surface 212a of the tooth 212.

[0042] The effects obtained by the third embodiment will be described below. In the resolver 1 with the speed detection function according to the third embodiment, the gear 210 is provided with the teeth 212 so as to protrude radially outward from the disk 211. The first core end 222 or the magnetic pole tip 223 is configured to face the side surface 212a of the teeth 212 that forms the same plane as the first surface 211a of the disk 211. Here, the teeth 212 protrude radially outward from the disk 211, and therefore do not protrude from the disk 211 in a direction parallel to the axial direction of the rotating shaft 110. This makes it possible to reduce the size of the detection unit 220 in the axial direction of the rotating shaft 110. This makes it possible to realize a resolver 1 with a speed detection function that is not enlarged in the radial direction and is not enlarged in the axial direction by adding the speed sensor unit 200 to the resolver unit 100. [Explanation of symbols]

[0043] 1 resolver with speed detection function, 10 case, 100 resolver section, 110 rotating shaft, 120 transformer section, 121 stator transformer section, 122 rotor transformer section, 130 rotor, 131 rotor core, 132 rotor coil, 140 stator, 141 stator core, 142 stator coil, 200 speed sensor section, 210 gear, 211 disk, 211a first surface, 211b second surface, 212 teeth, 212a side, 213 auxiliary magnet, 220, 220a, 220b detection section, 221 core, 222 first core end, 223 magnetic pole tip, 224 second core end, 225 detection winding, 226 magnet.

Claims

1. a resolver unit (100) having a rotating shaft (110) and outputting a signal according to an angle of the rotating shaft (110); a speed sensor unit (200) including a gear (210) rotating together with the rotating shaft (110) and at least one detection unit (220), and outputting a speed signal corresponding to the rotation of the gear (210); Equipped with The gear (210) has at least one tooth (212) on an end of a disk (211); The detection unit (220) A core (221) wound with a detection winding (225); a first core end (222) of the core (221); a magnet (226) in contact with a second core end (224) of the core (221); Equipped with The first core end (222) is disposed opposite the teeth (212), The core (221) is arranged so that a direction along the axis of the core (221) is parallel to an axial direction of the rotating shaft (110). A resolver with speed detection function.

2. the teeth (212) are configured to protrude axially towards the first core end (222); A resolver having a speed detection function according to claim 1.

3. The gear (210) has the teeth (212) on a first surface of the disk (211) and an auxiliary magnet (213) on a second surface of the disk (211). A resolver having a speed detection function according to claim 1.

4. The detection unit (220) is provided in plurality, The plurality of detection portions (220) are arranged to be in different phases with respect to the teeth (212). A resolver having a speed detection function according to claim 1.

5. a magnetic pole tip (223) having a cross section smaller than the cross section of the core (221) and determined according to the thickness of the tooth (212) is further provided at the first core end (222) so as to face the tooth (212); A resolver having a speed detection function according to claim 1.

6. The resolver unit (100) includes a rotor (130) rotatable together with the rotating shaft (110), and a cylindrical stator (140) fixedly provided around the rotor (130), the speed sensor portion (200) is configured so as not to exceed the outer diameter of the stator (140); The resolver unit (100) and the speed sensor unit (200) are housed in a cylindrical case (10). A resolver having a speed detection function according to any one of claims 1 to 5.

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