JP3755799B2 - Stepping motor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a stepping motor, and more specifically, accommodates in a case member having a case member having a mounting surface attached to a fixed member of a meter and a rotor serving as a power source for driving an output shaft. An excitation means for exciting the rotor; and a terminal penetrating the excitation means and conducting electric power from the outside to the excitation means, wherein the excitation means is provided on the mounting surface of the case member. The first inner surface located on the back side is disposed with a space between the second inner surface facing the first inner surface, and one end of the terminal protruding from the mounting surface of the case member, The present invention relates to a stepping motor attached through the fixing member.
[0002]
[Prior art]
Conventionally, stepping motors have been used as actuator parts in the fields of various office automation equipment, home appliances, automobiles, and the like. For example, a vehicle instrument device that displays measured values such as a vehicle speed and an engine speed is mounted on the vehicle. In this vehicle instrument device, an internal unit that drives a pointer disposed on the front face of a dial A stepping motor is used.
[0003]
Here, an example of a conventional stepping motor used in a vehicle instrument device will be described with reference to a sectional view of the conventional stepping motor of FIG.
[0004]
In FIG. 5, reference numeral 50 denotes a stepping motor, and the stepping motor 50 has a case member having an attachment surface 52c attached to a wiring board (corresponding to a fixed member) 40 of the vehicle instrument device. The case member includes an upper case 51 and a lower case 52, and the bottom surface of the lower case 52 corresponds to the mounting surface 52c. The case member also accommodates a rotor 56 serving as a power source for driving the pointer shaft (output shaft) 57 and a coil 55 (corresponding to an excitation means) that is fixed to the stator 54 and excites the rotor 56. ing.
[0005]
The coil 55 has a space between the first inner surface 52d located on the back side of the mounting surface 52c of the lower case 52 and the second inner surface 51d of the upper case 51 facing the first inner surface 52d. Are arranged. Then, the stepping motor 50 is attached to the wiring board 40 of the vehicle instrument device by passing one end of the terminals 55c and 55d protruding from the attachment surface 52c of the lower case 52 from the through hole 41 provided in the wiring board 40. ing.
[0006]
[Problems to be solved by the invention]
However, in the conventional stepping motor 50 described above, there is a space between the coil 55 and the second inner surface 51d of the upper case 51, and the terminals 55c and 55d are provided through the coil 55. When the terminals 55c and 55d protruding from the mounting surface 52c of the stepping motor 50 are passed through the through-hole 41, if the hooks occur, the terminals 55c and 55d are detached from the coil 55 or moved. As a result, the coil 55 is disconnected.
[0007]
Therefore, in view of the above-described problems, an object of the present invention is to provide a stepping motor that can prevent the coil from being disconnected at the time of attachment.
[0008]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, a stepping motor according to the present invention, which is made according to the present invention, accommodates a case member having a mounting surface attached to a fixed member of a meter and a rotor serving as a power source for driving an output shaft. The excitation means housed in the case member to excite the rotor, and a linear bar-shaped terminal provided through the excitation means and conducting electric power from the outside to the excitation means. The means is disposed on the first inner surface located on the back side of the mounting surface of the case member, with a space between the second inner surface facing the first inner surface, and the mounting of the case member. In a stepping motor that is attached by penetrating one end of the terminal protruding from the surface to the fixing member, when the one end of the terminal penetrates the fixing member, The urging direction and further comprising a movement restricting means for restricting the movement of the terminal in the opposite direction.
[0009]
According to the stepping motor of the present invention as set forth in the first aspect, one end of the terminal penetrating the excitation means is provided so as to protrude from the mounting surface of the case member. Then, when the one end is passed through the fixing member, even if a force in the direction opposite to the mounting direction with respect to the fixing member acts on the terminal due to occurrence of catching or the like, the movement of the terminal is restricted by the movement restricting means. . Therefore, when the terminal protruding from the mounting surface of the stepping motor is passed through the fixing member, even if a force in the direction opposite to the mounting direction with respect to the fixing member acts on the terminal due to occurrence of catching or the like, the terminal is moved by the movement regulating means Can be prevented from moving. Therefore, it is possible to prevent disconnection of the excitation means caused by a cause such as the terminal coming out of the excitation means or moving. Also, when the terminal is formed by automatic press-fitting to the exciting means, the terminal must be in the form of a straight bar, and therefore it is easy to come off due to heat applied when soldering the lead wire to the terminal. Since the movement of the terminal is restricted by the movement restricting means, the conventional exciting means and the terminal can be used as they are.
[0010]
In order to solve the above-mentioned problem, the invention according to claim 2 is the stepping motor according to claim 1, wherein the movement restricting means is opposed to the other end of the terminal provided on the second inner surface. It is characterized by comprising protrusions.
[0011]
According to the stepping motor of the present invention described in the second aspect, the protrusion facing the other end of the terminal is provided on the second inner surface of the case member. Therefore, when one end of the terminal protruding from the mounting surface of the stepping motor is passed through the fixing member, even if a force in the direction opposite to the mounting direction with respect to the fixing member is applied to the terminal due to occurrence of a catch or the like, The terminal can be prevented from moving by the end being in contact with the protrusion that is the movement restricting means. Therefore, it is possible to prevent disconnection of the excitation means caused by a cause such as the terminal coming out of the excitation means or moving with a simple configuration in which a protrusion is formed on the second inner surface of the case member.
[0012]
According to a third aspect of the present invention, there is provided the stepping motor according to the first aspect, wherein the movement restricting means extends to the second inner surface or the vicinity of the second inner surface. It is the other end of the terminal.
[0013]
In the stepping motor according to the third aspect of the present invention, the terminal is formed such that the other end extends to the second inner surface of the case member or near the inner surface, and is penetrated by the excitation means. Therefore, when one end of the terminal protruding from the mounting surface of the stepping motor is passed through the fixing member, even if a force in the direction opposite to the mounting direction with respect to the fixing member is applied to the terminal due to occurrence of a catch or the like, Since the end contacts the second inner surface of the case member, the terminal can be prevented from moving. Therefore, it is possible to prevent disconnection of the excitation means caused by a cause such as the terminal coming out of the excitation means or moving only by extending the other end of the terminal to the second inner surface of the case member or near the second inner surface. it can.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment in which a stepping motor according to the present invention is applied to a vehicle instrument device will be described with reference to the drawings of FIGS. In the present embodiment, the same or corresponding parts as those described in the prior art will be described with the same reference numerals.
[0015]
Here, FIG. 1 is a perspective view showing an external appearance of the stepping motor according to the present invention, FIG. 2 is an exploded perspective view of the stepping motor of FIG. 1, and FIG. 3 is an arrow direction passing through the line AA in FIG. FIG.
[0016]
As shown in FIGS. 1 to 3, the stepping motor 50 includes an upper case 51 and a lower case 52 formed of synthetic resin or the like. The upper case 51 and the lower case 52 are positioned by fitting the fitting protrusions 52a of the lower case 52 corresponding to the pair of fitting holes 51a of the upper case 51, respectively. The hole 51b is engaged with and fixed to an engagement protrusion 52b provided on the outer wall of the lower case 52.
[0017]
On the upper surface of the upper case 51, a convex portion 51c having a through hole through which a later-described pointer shaft (corresponding to an output shaft) 57 passes is provided. An arm-like hook 51e is provided on the side wall of the upper case 51, and an end of the hook 51e has an engaging portion that penetrates the wiring board 40 and engages the surface thereof. Further, the outer surface of the bottom plate constituting the lower case 52 is a mounting surface 52c fixed to a wiring board (corresponding to a fixing member) 40 of the vehicle instrument device, and the lower case is located behind the mounting surface 52c. The inner surface of 52 is the first inner surface 52d.
[0018]
The lower case 52 further includes a bearing 52e for rotatably fitting a later-described pointer shaft 57, a rotor bearing 52f to which one end of the rotor shaft 53a is fixed, and one end of the gear shaft 53b. And a gear bearing portion 52g. The portions fixed to the lower case 52 of the rotor shaft member 53a and the gear shaft member 53b are knurled to prevent the rotor shaft member 53a and the gear shaft member 53b from rotating.
[0019]
54 is a stator, and the stator 54 is formed by laminating metal plates such as silicon steel plates in a frame shape corresponding to the shape of the lower case 52. The stator 54 is provided with first and second extending portions 54a and 54b and a hole 54c through which the gear shaft member 53b passes.
[0020]
A coil 55 is attached to the elongated portion 54a of the stator 54 and corresponds to an excitation means. The coil 55 is a terminal press-fitted into the bobbin 55a by winding a copper wire 55b around a bobbin 55a formed of a synthetic resin such as plastic. Both ends of the copper wire 55b, that is, the winding start and the winding end are electrically connected to 55c and 55d by means of soldering or the like.
[0021]
One end of each of the terminals 55 c and 55 d passes through a terminal through hole 52 h provided in the lower case 52 and protrudes from the mounting surface 52 d of the lower case 52. The other ends of the terminals 55c and 55d are in contact with the protrusion 51f provided on the second inner surface 51d. As a result, even if the projections 51f cause one end of the terminals 55c and 55d protruding from the mounting surface 52c of the lower case 52 to penetrate from the lower case 52, the mounting direction with respect to the wiring board 40 is opposite. The movement of the terminals 55c and 55d in the direction is restricted. Therefore, as is apparent from the above description, the protrusion 51f functions as a movement restricting means described in the claims.
[0022]
A rotor 56 is a driving source of the stepping motor 50. The rotor 56 is formed of a plastic magnet and has a through hole (not shown) through which the rotor shaft member 53a passes. A rotor gear 56 a having a through hole connected to the through hole of the rotor 56 is mounted on the upper surface of the rotor 56.
[0023]
Reference numeral 57 denotes a pointer shaft to which the pointer 20 is attached at the tip. The pointer shaft 57 is formed of a metal member, and a pointer gear 57a made of, for example, plastic is fixed to the pointer shaft 20 by press-fitting. One end of the pointer shaft 57 protrudes from the convex portion 51 c of the upper case 51, and the other end is fitted to the bearing portion 52 c of the lower case 52.
[0024]
58 is a gear that transmits the rotation of the rotor 56 to the pointer shaft 57. The gear 58 is made of a synthetic resin such as plastic, for example, a large gear that meshes with the rotor gear 56a of the rotor 56, and meshes with the pointer gear 57a. A small gear with a small diameter is integrally formed.
[0025]
Next, attachment of the stepping motor to the wiring board (fixing member) 40 will be described.
First, the coil 55 is attached to each of the first and second extending portions 54a and 54b of the stator 54, and the rotor shaft member 53a and the gear are connected to the rotor bearing portion 52f and the gear bearing portion 52g of the lower case 52. One end of each shaft member 53b is mounted. In this state, the gear shaft member 53b is positioned through the hole 54a of the stator 54, and the terminals 55c and 55d of the coil 55 are passed through the terminal through holes 52h of the lower case 52 so that the stator 54 is placed in the lower case. Attach to 52.
[0026]
The rotor 56 is rotatably fitted to the rotor shaft member 53a, and the pointer shaft 57 to which the pointer gear 57a is fixed is rotatably fitted to the bearing portion 52c of the lower case 52. Then, the gear 58 is rotatably attached to the gear shaft member 53b so that the large gear of the gear 58 meshes with the rotor gear 56a of the rotor 56 and the small gear meshes with the pointer gear 57a.
[0027]
The tip of the pointer shaft 57 protrudes from the convex portion 51c of the upper case 51, and the other end of each of the rotor shaft member 53a and the gear shaft member 53b is provided on the second inner surface of the upper case 51 (not shown). ), The fitting projection 52a of the lower case 52 is fitted and positioned in the fitting hole 51a of the upper case 51, and the engagement hole 51b of the upper case 51 is engaged with the engagement projection 52b of the lower case 52. Thus, the upper case 51 and the lower case 52 are fixed.
[0028]
The stepping motor 50 formed in this way is attached to the wiring board 40 by attaching a hook 51e provided on the side wall of the upper case 51 to an attachment hole (not shown) of the wiring board 40 and from the attachment surface 52c of the lower case 51. One end of each of the protruding terminals 55c and 55d is passed through a through hole 41 provided in the wiring board 40, and the surface of the wiring board 40 and the mounting surface 52c of the stepping motor 50 are brought into contact with each other and fixed. The terminals 55c and 55d protruding from the back surface of the wiring board 40 are soldered to be electrically connected.
[0029]
The stepping motor 50 attached to the wiring board 40 can supply an electric signal to the terminals 55c and 55d through a wiring pattern provided on the wiring board 40, and supplies an electric signal corresponding to the measurement amount to the coil 55. Thus, the rotation of the rotor 56 according to the measured amount is transmitted to the pointer shaft 57 via the gear 58, and the pointer 20 attached to the tip of the pointer shaft 57 is driven according to the measured amount.
[0030]
In addition, when the terminals 55c and 55d protruding from the mounting surface 52c of the stepping motor 50 are passed through the through hole 41 of the wiring board 40, the attachment direction of the terminals 55c and 55d with respect to the wiring board 40 is caused by occurrence of catching or the like. Even if a force in the opposite direction is applied, the other ends of the terminals 55c and 55d are in contact with the second inner surface 51d of the upper case 51, so that the movement in the direction opposite to the mounting direction of the terminals 55c and 55d is restricted. Is done.
[0031]
As described above, according to the stepping motor 50 of the present invention, when the terminals 55c and 55d protruding from the mounting surface 52c of the stepping motor 50 are passed through the wiring board (fixing member) 40, the terminals are generated due to the occurrence of catching or the like. Even if a force in the direction opposite to the mounting direction with respect to the wiring board 40 acts on 55c and 55d, the second inner surface (movement restricting means) 51d of the upper case 51 moves the terminals 55c and 55d in the opposite direction. Can be prevented.
[0032]
Accordingly, disconnection of the coil 55 caused by causes such as the terminals 55c and 55d coming out of the coil (exciting means) 55 and moving can be prevented. In addition, when the terminals 55c and 55d are formed in the coil 55 by automatic press-fitting, the terminals 55c and 55d must have a straight bar shape. Although it is easy, since the movement of the terminals 55c and 55d in the opposite direction is restricted by the projection 51f which is the movement restricting means of the present invention, the conventional coil 55 and terminals 55c and 55d can be used as they are. .
[0033]
In the above-described embodiment, the case where the movement restricting means is realized by the protrusion 51f provided on the second inner surface 51d of the upper case 51 has been described. However, the present invention is not limited to this. It is possible to adopt another embodiment in which the movement restricting means is realized by the members and methods.
[0034]
Here, an example of another embodiment will be described with reference to an enlarged cross-sectional view showing another embodiment in the arrow direction passing through the line AA in FIG. 4 of FIG. Since the basic configuration of the stepping motor 50 is the same as that of the present embodiment described above, detailed description is omitted and only different members will be described.
[0035]
The upper case 51 shown in FIG. 4 is not provided with the protrusion 51f provided on the second inner surface 51d of the upper case 51 of the above-described embodiment, and the upper case 51 (FIG. 5)). Further, the terminals 55 c and 55 d are formed so that the other ends thereof extend to the second inner surface 51 d of the upper case 51 and penetrate the coil 55.
[0036]
Therefore, when one end of the terminals 55c and 55d protruding from the mounting surface 52c of the stepping motor 50 is passed through the wiring board 40, the terminals 55c and 55d are moved in the direction opposite to the mounting direction with respect to the wiring board 40 due to the occurrence of catching or the like. Even if this force is applied, the other ends of the terminals 55c and 55d come into contact with the second inner surface 51d of the upper case 51, so that the terminals 55c and 55d can be prevented from moving.
[0037]
Accordingly, the terminal 55c, 55d is simply extended to the second inner surface 51d of the upper case 51 to prevent disconnection of the excitation means caused by the terminal 55c, 55d coming out of the coil 55 or moving. be able to.
[0038]
In the present embodiment and the other embodiments described above, the case where the other ends of the terminals 55c and 55d are fixed in contact with the second inner surface 51d and the protrusion 51f of the upper case 51 has been described. The present invention is not limited to this, and even if the length of the terminals 55c and 55d is the length up to the vicinity of the second inner surface 51d and the protrusion 51f, the same effect as the above-described embodiment can be obtained. it can.
[0039]
In the above-described embodiment, the wiring board 40 to which the stepping motor 50 is attached has been described as a fixing member. However, the present invention is not limited to this, and the objects to which the stepping motor 50 is attached are the dial plate 10 and the light guide plate. In the case of 30, the case 60, or the like, the attachment target corresponds to the fixing member.
[0040]
Furthermore, although the case where the mounting surface 52c of the stepping motor 50 is provided in the lower case 52 has been described in the present embodiment described above, the present invention is not limited to this, and the upper case 51 from which the pointer shaft 57 protrudes. Can be provided.
[0041]
【The invention's effect】
As described above, according to the stepping motor of the present invention described in claim 1, when the terminal protruding from the mounting surface of the stepping motor is passed through the fixing member, the terminal is attached to the fixing member due to occurrence of catching or the like. Even when a force in the opposite direction is applied, the movement of the terminal can be prevented by the movement restricting means. Therefore, it is possible to prevent disconnection of the excitation means caused by a cause such as the terminal coming out of the excitation means or moving. Also, when the terminal is formed by automatic press-fitting to the exciting means, the terminal must be in the form of a straight bar, and therefore it is easy to come off due to heat applied when soldering the lead wire to the terminal. Since the movement of the terminal is restricted by the movement restricting means, the conventional exciting means and the terminal can be used as they are.
[0042]
According to the invention described in claim 2, in addition to the effect of the invention described in claim 1, when the one end of the terminal protruding from the mounting surface of the stepping motor is passed through the fixing member, the terminal is caused by occurrence of a catch or the like. Even if a force in the direction opposite to the mounting direction with respect to the fixing member acts, the terminal can be prevented from moving by the other end of the terminal coming into contact with the protrusion that is the movement restricting means. Therefore, it is possible to prevent disconnection of the excitation means caused by a cause such as the terminal being detached from the excitation means or moving with a simple configuration in which a protrusion is formed on the second inner surface of the case member.
[0043]
According to the invention described in claim 3, in addition to the effect of the invention described in claim 1, when one end of the terminal protruding from the mounting surface of the stepping motor is passed through the fixing member, the terminal is caused by occurrence of a catch or the like. Even if a force in the direction opposite to the mounting direction with respect to the fixing member is applied, the terminal can be prevented from moving by the other end of the terminal being in contact with the second inner surface of the case member. Therefore, it is possible to prevent disconnection of the excitation means caused by a cause such as the terminal coming out of the excitation means or moving only by extending the other end of the terminal to the second inner surface of the case member or near the second inner surface. There is an effect that can be done.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an external appearance of a stepping motor according to the present invention.
FIG. 2 is an exploded perspective view of the stepping motor of FIG.
3 is an enlarged cross-sectional view in the direction of the arrow passing through the line AA in FIG. 1. FIG.
4 is an enlarged cross-sectional view showing another embodiment in the direction of the arrow passing through the line AA in FIG. 1. FIG.
FIG. 5 is a cross-sectional view of a conventional stepping motor.
[Explanation of symbols]
40 Wiring board (fixing member)
50 Stepping motor 51 Upper case (case member)
51d Second inner surface 51f Protrusion 52 Lower case (case member)
52c Mounting surface 52d First inner surface 55c, d Terminal 56 Rotor 57 Pointer shaft (output shaft)
58 Gear

Claims (3)

A case member having a mounting surface to be attached to a fixed member of the instrument; an excitation means for energizing the rotor housed in the case member in which a rotor serving as a power source for driving the output shaft is housed; A linear rod-like terminal that is provided through the means and that conducts electric power from the outside to the excitation means, and the excitation means is on the first inner surface located on the back side of the mounting surface of the case member, A stepping step which is disposed with a space between the second inner surface facing the first inner surface and is attached by penetrating one end of the terminal protruding from the mounting surface of the case member into the fixing member. In the motor
A stepping motor further comprising movement restricting means for restricting movement of the terminal in a direction opposite to a mounting direction with respect to the fixing member when one end of the terminal is passed through the fixing member. The stepping motor according to claim 1, wherein the movement restricting unit is configured by a protrusion facing the other end of the terminal provided on the second inner surface. The stepping motor according to claim 1, wherein the movement restricting means is the other end of the terminal extending to the second inner surface or the vicinity of the second inner surface.

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