CN218335708U - Fixed shaft type screw rod stepping motor - Google Patents

Abstract

The utility model discloses a fixed axle formula lead screw step motor, include: the motor assembly comprises a rotor set and a stator set, wherein the rotor set is matched with the stator set; the stator set is provided with a containing cavity for containing the rotor set; the rotor set comprises a rotor shaft suitable for making rotary motion and a pair of bearings respectively arranged on two shaft ends of the rotor shaft; the rotor shaft is provided with a shaft hole formed with an internal thread; the screw rod is suitable for penetrating through the shaft hole so that the rotary motion of the rotor shaft is converted into the linear motion of the screw rod; the sliding rail assembly comprises a sliding rail shell which is suitable for being partially inserted and fixed in the containing cavity and is abutted with one bearing of the rotor set, and a spline shaft which penetrates through the sliding rail shell; one end of the screw rod is inserted into the slide rail shell and fixedly connected with the spline shaft.

Description

Fixed shaft type lead screw stepping motor

Technical Field

The utility model relates to the technical field of motors, especially, relate to a fixed axle formula lead screw step motor.

Background

The fixed shaft type screw rod stepping motor is a linear transmission mechanism, and the general structure of the fixed shaft type screw rod stepping motor comprises a rotor assembly, a stator assembly and a screw rod connected with the rotor assembly; wherein the rotor assembly is supported within the inner cavity of the stator assembly by bearings. In the prior art, a large number of fixed shaft type lead screw stepping motors with large models are used, for example, fixed shaft type lead screw stepping motors of 20-57 series models, wherein a slide rail and the motor are fixed by welding or glue. Under the condition of small use space, particularly when the outer diameter of the motor is required to be less than 20mm, the sliding rail of the fixed shaft type screw rod stepping motor of the conventional machine type is difficult to be fixed with the motor through welding due to the limitation of size, and if the sliding rail is fixed by glue, the requirement on the dosage precision of the glue is high, the glue is easy to overflow to a bearing in the motor, and the normal use of the motor is influenced. Therefore, in the case of a small-sized motor used in the fixed shaft type lead screw stepping motor, the welding and bonding methods conventionally used in the prior art have limitations, that is, the two conventional structures are not suitable for the application of the small-sized motor.

Further, for a stator assembly used in a fixed shaft type screw stepping motor, a structure is generally adopted in which bearing chambers for accommodating bearings are provided on a front end cover and a rear end cover of an outer housing of the stator assembly, respectively. On the basis of the structure, the bearing chambers of the front end cover and the rear end cover are respectively matched with the bearing excircle parts of the front side bearing and the rear side bearing of the rotor assembly, the excircle parts of the bearing chambers of the front end cover and the rear end cover are matched with the stator inner hole of the stator assembly, and the rotor assembly is ensured to be positioned in the middle of the stator inner hole. The existing assembly method needs a plurality of components for assembly positioning, and the assembly precision of the existing stepping motor is difficult to improve due to the influence of the machining precision of each component.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a fixed axle formula lead screw step motor to the solution improves the technical problem to the adaptability that adopts small-size motor element.

The utility model discloses a fixed axle formula lead screw step motor realizes like this:

a fixed shaft lead screw stepper motor comprising: the motor assembly comprises a rotor set and a stator set, wherein the rotor set is matched with the stator set; the stator set is provided with a containing cavity for containing the rotor set; the rotor set comprises a rotor shaft suitable for making rotary motion and a pair of bearings respectively arranged on two shaft ends of the rotor shaft; the rotor shaft has a shaft hole formed with an internal thread;

the screw rod is suitable for penetrating through the shaft hole so that the rotary motion of the rotor shaft is converted into the linear motion of the screw rod;

the sliding rail assembly comprises a sliding rail shell which is suitable for being partially inserted and fixed in the containing cavity and is abutted with one bearing of the rotor set, and a spline shaft which penetrates through the sliding rail shell; one end of the screw rod is inserted into the sliding rail shell and fixedly connected with the spline shaft.

In an optional embodiment of the present invention, the connecting portion of the screw rod for engaging with the spline shaft includes an external thread portion and an optical axis portion sequentially arranged along an axial direction of the screw rod; and

the spline shaft is internally provided with a connecting hole for matching with the connecting part; an internal thread structure matched with the external thread part and a light shaft hole matched with the light shaft part are formed in the connecting hole.

In an alternative embodiment of the present invention, the optical axis hole is in clearance fit with the optical axis portion.

In an alternative embodiment of the present invention, the external thread portion is formed on a circumferential side wall of the shaft end of the screw rod; or alternatively

The optical axis part is formed on the circumferential side wall of the shaft end of the screw rod.

In an optional embodiment of the present invention, the internal threads are uniformly distributed on the inner wall of the shaft hole along the axial direction of the shaft hole; or

The internal thread is formed on an inner wall of a partial region of the shaft hole.

In an alternative embodiment of the present invention, a position limiting structure adapted to abut against the bearing is further disposed in the accommodating cavity and at a side end of the bearing deviating from the slide rail housing in the rotor set.

The utility model discloses in the optional embodiment, limit structure including inlay establish on accepting the inner wall of chamber and with rotor group in deviate from the gasket of slide rail housing's bearing butt and with the gasket deviate from the jump ring of rotor group's side butt.

In an optional embodiment of the present invention, a spacing gasket adapted to abut against a shaft end of the spline shaft connecting lead screw is provided between the slide rail housing and the corresponding bearing.

In an optional embodiment of the present invention, the sliding rail housing is connected to the accommodating cavity by a screw thread; and

the outer side wall of the part of the slide rail shell inserted into the containing cavity is provided with a first external thread part.

In an alternative embodiment of the present invention, the first external thread portion is sunk in the accommodation cavity; and

a second external thread part with the outer diameter smaller than that of the first external thread part is formed on the outer side wall of the slide rail shell; the second external thread part is suitable for being in threaded connection with a tightening nut;

when the clamping nut is in locking fit with the second external thread part, the clamping nut is abutted to the shaft end of the stator set, which is used for connecting the sliding rail shell.

By adopting the technical scheme, the utility model discloses following beneficial effect has: the utility model discloses a fixed axle formula lead screw step motor has adopted integrative injection moulding's stator group for slide rail set can directly insert the mode of receiving the chamber through the part and realize and accept the relative fixation in chamber, and the fixed mode that can be the interference at this in-process also can be threaded connected mode, thereby makes fixed axle formula lead screw step motor under this kind of structure can be applicable to small-size motor element, has improved overall structure to the suitability of not unidimensional motor promptly.

Furthermore, the utility model discloses a connection structure between knurling axle and the lead screw not only can improve the joint strength between lead screw and the integral key shaft, can also compromise the concentricity of both cooperation in-processes.

Drawings

Fig. 1 is a schematic view of the overall structure of the fixed shaft type lead screw stepping motor of the present invention;

fig. 2 is a schematic structural diagram of a stator set of the fixed shaft type lead screw stepping motor of the present invention;

fig. 3 is a schematic structural diagram of a rotor set of the fixed shaft type lead screw stepping motor of the present invention;

fig. 4 is a schematic structural view of the stator set and the rotor set of the fixed shaft type lead screw stepping motor of the present invention in a matching state;

fig. 5 is a schematic structural view of a slide rail assembly of the fixed shaft type lead screw stepping motor of the present invention;

fig. 6 is a schematic view of a connection structure between a spline shaft and a screw rod of the fixed shaft type screw rod stepping motor of the present invention;

fig. 7 is a schematic view of the fitting structure of the slide rail housing and the spline shaft of the fixed shaft type lead screw stepping motor of the present invention;

fig. 8 is a schematic view of the fitting structure of the spline hole and the spline shaft of the fixed shaft type lead screw stepping motor of the present invention;

fig. 9 is a schematic structural view of the fastening nut of the fixed shaft type lead screw stepping motor of the present invention.

In the figure: the structure comprises a shell 11, an injection molded body 12, a spline hole 13, a spline shaft 14, a flat surface 211, an injection molded hole 15, a clamping nut 21, a second external thread part 22, a first external thread part 23, a limiting gasket 3, a screw rod 5, an external thread part 51, a smooth shaft part 52, a rotor shaft 6, a shaft hole 61, a bearing 7, a stator group 8, an accommodating cavity 82, an installation support 83, a gasket 91, a clamp spring 92 and a gap K.

Detailed Description

In order that the present invention may be more readily and clearly understood, the following detailed description of the present invention is provided in connection with the accompanying drawings.

Example 1:

referring to fig. 1 to 8, the present embodiment provides a fixed shaft type lead screw stepping motor, including: motor element, lead screw 5 and the slide rail set spare of cooperation use.

Roughly speaking, first is a motor assembly comprising a stator group 8 and a rotor group built into the stator group 8; the stator assembly 8 of this embodiment is an integrally injection-molded structure, and a receiving cavity 82 for receiving the rotor assembly is directly formed during the injection molding process, and a pair of mounting brackets 83 are directly and integrally injection-molded at two ends of the stator assembly 8, and the receiving cavity 82 extends into the pair of mounting brackets 83. Generally speaking, the two axial ends of the stator assembly 8 of the present embodiment are open to the receiving cavity 82, that is, the two axial ends of the stator assembly 8 of the present embodiment are not provided with end caps.

On the basis of the above structure, in the rotor set, the rotor set adopted in this embodiment includes a rotor shaft 6 adapted to make a rotation motion and a pair of bearings 7 respectively arranged on two shaft ends of the rotor shaft 6; during assembly of the rotor assembly with the receiving cavity 82, the integral rotor assembly is integrated into the receiving cavity 82. After the rotor set is received in the receiving chamber 82, a pair of bearings 7 are respectively located in the mounting brackets 83.

The rotor shaft 6 in the rotor set is used for forming the coupling with the screw rod 5 and is suitable for being converted into the linear motion of the screw rod 5 through the rotary motion of the rotor shaft 6. The rotor shaft 6 has a shaft hole 61 for receiving the lead screw 5. In view of the use requirement of the transformation of the motion trail, in an optional implementation condition, a nut is arranged in the shaft hole 61, and then the screw rod 5 is matched with the nut through threads, so that the screw rod 5 can do linear motion under the rotation action of the rotor shaft 6. In a further alternative embodiment, in order to simplify the structure of the integral motor assembly, an internal thread 62 is directly formed on the inner wall of the axial hole 61 to facilitate the screw-engagement with the lead screw 5. In this case, it should be noted that the internal threads 62 may be uniformly distributed on the inner wall of the shaft hole 61 along the axial direction of the shaft hole 61; or the female screw 62 may be formed only on the inner wall of a partial region of the shaft hole 61. That is, the specific design form of the internal thread 62 is not limited in this embodiment, that is, the use requirement of this embodiment is satisfied as long as the shaft hole 61 and the lead screw 5 are matched to enable the lead screw 5 to normally perform linear reciprocating motion.

Furthermore, the slide rail assembly: the slide rail housing is suitable for being partially inserted and fixed in the accommodating cavity 82 and abutted against one bearing 7 of the rotor set, namely the slide rail housing not only realizes the fixation of the slide rail housing in the process of being assembled and fixed with the accommodating cavity 82 of the stator set 8, but also realizes the abutment against one axial end face of the rotor set in the process of being fixed, so that the assembly and fixation structure of one axial end face of the rotor set can be omitted for the rotor set per se.

On the basis of the above structure, it should be noted that, for the integral rotor set, one shaft end of the integral rotor set is pressed by the sliding track housing, and for the shaft end of the rotor set departing from the sliding track housing, in this embodiment, referring to the attached drawings, an optional case is illustrated, and a limiting structure suitable for abutting against the bearing 7 is further disposed in the accommodating cavity 82 and at one side end of the bearing 7 of the rotor set, which is located away from the sliding track housing. That is to say, the limiting structure and the slide rail housing together form a clamping fixation for the rotor set, so that the rotor set is prevented from axial movement during use.

For the above limiting structure, for example, in a specific manner, the limiting structure includes a gasket 91 embedded on the inner wall of the accommodating cavity 82 and abutted against the bearing 7 of the rotor set, which is away from the slide rail housing, and a snap spring 92 abutted against a side end of the gasket 91, which is away from the rotor set. The mode that adopts jump ring 92 cooperation gasket 91 not only the installation is convenient, and overall cost is also lower moreover.

Furthermore, spline holes 13 are formed through the slide rail housing, the spline holes 13 extend to two different end surfaces of the slide rail housing facing the motor assembly and away from the motor assembly, the spline holes 13 are used for assembling a spline shaft 14, and one end of the screw rod 5 is inserted into the spline holes 13 to realize the fixed connection between the screw rod 5 and the spline shaft 14.

Regarding the manner of engagement between the screw 5 and the spline shaft 14, the following structure is adopted in the present embodiment for the purpose of achieving both concentricity and connection strength in the state of engagement between the two:

the connecting part of the screw rod 5 for matching with the spline shaft 14 comprises an external thread part 51 and an optical axis part 52 which are sequentially arranged along the axial direction of the screw rod 5; a connecting hole for matching and connecting the connecting part is arranged in the spline shaft 14; an internal thread structure adapted to the external thread portion 51 and an optical axis hole 61 adapted to the optical axis portion 52 are formed in the connection hole. The optical axis hole 61 is in clearance fit with the optical axis part 52. Here, for the external thread portion 51 and the optical axis portion 52 on the screw rod 5, the external thread portion 51 may be formed on the circumferential side wall of the shaft end of the screw rod 5, and in the process of inserting and fitting the connecting portion of the screw rod 5, the external thread portion 51 firstly enters the connecting hole of the spline shaft 14; the optical axis part 52 may be formed on a circumferential side wall of the shaft end of the screw 5, and the optical axis part 52 enters the connecting hole of the spline shaft 14 first in the process of inserting and matching the connecting part of the screw 5. Both of the above situations satisfy the use requirement of the present embodiment, and the present embodiment is not limited in any way.

Through the structural design, tight connection can be ensured through the matching of the external thread part 51 and the internal thread structure, the concentricity of the screw rod 5 and the spline shaft 14 can be controlled through the matching of the smooth shaft part 52 and the optical axis hole 61, the screw rod 5 or the spline shaft 14 is prevented from being clamped, a small gap K is inevitably formed between the screw rod 5 and the internal thread of the rotor shaft 6, a gap K is also inevitably formed between the spline shaft 14 and the spline hole 13, the influence of external vibration is received in the transportation process, the connection part of the screw rod 5 and the spline shaft 14 is subjected to radial force, under the condition that the external diameters of the screw rod 5 and the spline shaft 14 are small, the influence of the force transmitted by the vibration on the connection of the screw rod 5 and the spline shaft 14 is large, the connection between the screw rod 5 and the spline shaft 14 is easy to loose or deform, and through the connection structure of the embodiment, the connection strength between the screw rod 5 and the spline shaft 14 can be improved, the influence on the connection of the screw rod 5 and the spline shaft 14 is greatly reduced, and the stability and reliability between the spline shaft 14 and the screw rod 5 are ensured.

In an alternative embodiment, the slide rail housing includes an outer housing 11 and an injection molded body 12 injection molded into the outer housing 11, and the spline hole 13 is integrally molded into the injection molded body 12. The casing 11 body has one or more injection molding hole 15, and the surface of injection molding body 12 has the arch of fixing in injection molding hole 15, fixes injection molding body 12 through injection molding hole 15, not only can guarantee injection molding body 12's intensity, and injection molding body 12 is difficult for droing moreover. And meanwhile, the spline hole 13 formed after injection molding has a certain degree of lubrication, so that the friction between the spline hole and the spline shaft 14 is reduced.

Finally, regarding the fixing manner between the slide rail housing and the accommodating cavity 82 of the stator assembly 8 in this embodiment, since the stator assembly 8 is an integral injection molding structure, the slide rail housing can be fixed in the accommodating cavity 82 by an interference fit manner, and can also be relatively fixed between the slide rail housing and the accommodating cavity 82 by a threaded connection manner, which manner is specifically adopted to achieve the purpose of fixing the slide rail housing, which is not absolutely limited in this embodiment.

Example 2:

referring to fig. 1 to 8, on the basis of the fixed shaft type lead screw stepping motor of embodiment 1, a limiting gasket 3 adapted to abut against the spline shaft 14 to connect with the shaft end of the lead screw 5 is interposed between the slide rail housing of the fixed shaft type lead screw stepping motor and the corresponding bearing 7. When the limiting gasket 3 abuts against the spline shaft 14, the connecting part of the screw 5 for connecting the spline shaft 14 is located in the spline hole 13, that is, the spline shaft 14 cannot enter the rotor shaft 6 under the action of the limiting gasket 3 along with the linear reciprocating motion of the screw 5.

In conclusion, the screw rod 5 cannot run out of the spline hole 13 of the sliding rail shell in the process of linear motion through the arrangement of the limiting gasket 3, so that structural failure is avoided.

Example 3:

referring to fig. 1 to 9, on the basis of the fixed shaft type lead screw stepping motor of embodiment 1 or embodiment 2, the following structural design is further made on the basis of the fixed shaft type lead screw stepping motor provided in this embodiment:

first, the slide rail housing is engaged with the receiving cavity 82 of the stator assembly 8 by a screw connection, and on the basis of this, a first external screw thread portion 23 is formed on the outer side wall of the portion of the slide rail housing inserted into the receiving cavity 82.

When the first external thread portion 23 and the accommodating cavity 82 are locked in place by means of threaded connection, the first external thread portion 23 is recessed in the accommodating cavity 82, that is, for the shaft end of the stator pack 8 deviating from the limiting structure, relative to the shaft end of the first external thread portion 23 deviating from the limiting structure, a small axial gap K exists between the shaft end of the stator pack 8 deviating from the limiting structure and the shaft end of the first external thread portion 23 deviating from the limiting structure.

On the basis of the structure, a second external thread part 22 with the external diameter smaller than that of the first external thread part 23 is formed on the outer side wall of the slide rail shell; the second external thread portion 22 is adapted to be threadedly coupled to a jam nut 21; when the clamping nut 21 is in locking fit with the second external thread portion 22, the clamping nut 21 abuts against the shaft end of the stator set 8 for connecting the slide rail housing. Tightening of the nut 21 against the stator pack 8 is achieved. Here, the union nut 21 may be formed with a flat surface 211 at each of both side end surfaces thereof for easy installation. The sliding rail shell is tightly locked by the design of the clamping nut 21 so as to prevent the sliding rail shell from loosening.

It should also be noted that the design and use of the jam nut 21 in the present embodiment is also applicable to the configuration when the slide housing is in interference fit with the receiving cavity 82.

The above embodiments, further detailed description of the objects, technical solutions and advantages of the present invention, it should be understood that the above embodiments are only examples of the present invention, and are not intended to limit the present invention, and any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the scope of the present invention.

In the description of the present invention, it is to be understood that the terms indicating orientation or positional relationship are based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplification of description, and do not indicate or imply that the equipment or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," and "fixed" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate the directions or positional relationships based on the directions or positional relationships shown in the drawings, or the directions or positional relationships that the products of the present invention are usually placed when used, and are only for the convenience of describing the present invention and simplifying the description, but do not indicate or imply that the device or element indicated must have a specific direction, be constructed and operated in a specific direction, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used solely to distinguish one from another and are not to be construed as indicating or implying relative importance.

Furthermore, the terms "horizontal", "vertical", "overhang" and the like do not imply that the components are required to be absolutely horizontal or overhang, but may be slightly inclined. For example, "horizontal" merely means that the direction is more horizontal than "vertical" and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.

In the present disclosure, unless otherwise expressly stated or limited, the first feature may comprise both the first and second features directly contacting each other, and also may comprise the first and second features not being directly contacting each other but being in contact with each other by means of further features between them. Also, the first feature may be over, above or on the second feature including the first feature being directly above or obliquely above the second feature, or simply indicating that the first feature is at a higher level than the second feature. A first feature being below, beneath or beneath a second feature includes the first feature being directly below and obliquely below the second feature or simply indicating that the first feature is at a lesser level than the second feature.

Claims (10)

1. The utility model provides a fixed axle formula lead screw step motor which characterized in that includes:

the motor assembly comprises a rotor set and a stator set, wherein the rotor set is matched with the stator set; the stator set is provided with a containing cavity for containing the rotor set; the rotor set comprises a rotor shaft suitable for rotating and a pair of bearings respectively arranged on two shaft ends of the rotor shaft; the rotor shaft has a shaft hole formed with an internal thread;

the screw rod is suitable for penetrating the shaft hole so that the rotary motion of the rotor shaft is converted into the linear motion of the screw rod;

the sliding rail assembly comprises a sliding rail shell which is suitable for being partially inserted and fixed in the containing cavity and is abutted with one bearing of the rotor set, and a spline shaft which penetrates through the sliding rail shell; one end of the screw rod is inserted into the slide rail shell and fixedly connected with the spline shaft.

2. The fixed shaft type lead screw stepping motor according to claim 1, wherein the connection portion of the lead screw for engaging with the spline shaft comprises an external thread portion and an optical axis portion provided in this order in an axial direction of the lead screw; and

the spline shaft is internally provided with a connecting hole for matching and connecting the connecting part; an internal thread structure matched with the external thread part and a light shaft hole matched with the light shaft part are formed in the connecting hole.

3. The fixed axis lead screw stepper motor of claim 2, wherein the optical axis aperture is clearance fit with the optical axis portion.

4. The fixed shaft-type lead screw stepping motor according to claim 2 or 3, wherein the external thread part is formed on a circumferential side wall of a shaft end of the lead screw; or alternatively

The optical axis portion is formed on a circumferential side wall of a shaft end of the lead screw.

5. The fixed shaft screw stepping motor according to claim 1, wherein the internal threads are uniformly distributed on the inner wall of the shaft hole in the axial direction of the shaft hole; or alternatively

The internal thread is formed on an inner wall of a partial region of the shaft hole.

6. The fixed shaft lead screw stepping motor according to claim 1, wherein a limiting structure adapted to abut against the bearing is further disposed in the accommodating cavity and at a side end of the rotor set facing away from the bearing of the slide rail housing.

7. The fixed shaft type lead screw stepping motor according to claim 6, wherein the limiting structure comprises a gasket which is embedded on the inner wall of the accommodating cavity and abuts against a bearing in the rotor set, the bearing deviates from the slide rail shell, and a clamp spring which abuts against a side end of the gasket, the side end of the gasket deviates from the rotor set.

8. The fixed shaft type lead screw stepping motor according to claim 1, wherein a limit washer adapted to abut against a shaft end of the spline shaft connected lead screw is interposed between the slide rail housing and the corresponding bearing.

9. The fixed shaft lead screw stepper motor of claim 1, wherein the slide rail housing is in threaded engagement with the receiving cavity; and

the outer side wall of the part of the slide rail shell inserted into the containing cavity is provided with a first external thread part.

10. The fixed axis lead screw stepper motor as defined in claim 9, wherein the first externally threaded portion is recessed within a receiving cavity; and

a second external thread part with the outer diameter smaller than that of the first external thread part is formed on the outer side wall of the slide rail shell; the second external thread part is suitable for being in threaded connection with a clamping nut;

when the clamping nut is in locking fit with the second external thread part, the clamping nut is abutted to the shaft end of the stator set, which is used for connecting the sliding rail shell.

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