CN216472042U

CN216472042U - Nut and screw transmission device and car lifting jack

Info

Publication number: CN216472042U
Application number: CN202122954133.0U
Authority: CN
Inventors: 程远雄; 黎莎; 闫颖辉
Original assignee: Beijing Railway Institute of Mechanical and Electrical Engineering Group Co Ltd
Current assignee: Beijing Railway Institute of Mechanical and Electrical Engineering Group Co Ltd
Priority date: 2021-11-29
Filing date: 2021-11-29
Publication date: 2022-05-10
Anticipated expiration: 2031-11-29

Abstract

The utility model belongs to the technical field of lead screw transmission, and discloses a nut and screw transmission device and a car lifting jack. The nut and screw transmission device comprises a nut connecting seat, a screw rod and a working nut. The nut connecting seat is provided with connecting points, and each connecting point is connected with a bracket of the car lifting jack. The screw rod movably penetrates through the nut connecting seat. The working nut is connected with the nut connecting seat and forms a first joint and a second joint. The working nut and the nut connecting seat form a spherical pair or a cylindrical pair at a first joint. The nut attachment seat limits circumferential rotation of the work nut at the second interface. The working nut is in threaded connection with the lead screw. The resultant moment of the force of the bracket acting on each connection point is zero at a first point, which is the center of the sphere of the spherical pair or located on the axis of the cylindrical pair. The spherical pair or the cylindrical pair can eliminate the unbalance loading torque on the nut connecting seat, so that the eccentric loading torque cannot be applied to the working nut, the working nut cannot deflect relative to the screw rod, and the abrasion of the working nut is reduced.

Description

Nut and screw transmission device and car lifting jack

Technical Field

The utility model relates to the technical field of screw rod transmission, in particular to a nut and screw rod transmission device and a car lifting jack.

Background

When the transportation vehicle is maintained, the transportation vehicle needs to be supported by the vehicle lifting jack so as to overhaul the parts at the bottom of the vehicle, and after the overhaul is finished, the vehicle is lowered by the vehicle lifting jack. The lifting of the bracket is generally realized by adopting the screw nut transmission of the rail vehicle car lifting jack, but the adoption of the screw nut transmission can cause the prominent defect of large abrasion of the working nut, thereby bringing potential safety hazards to the car lifting jack.

At present, in order to reduce the abrasion of the nut, technical personnel mainly adopt methods of increasing driving power, monitoring and alarming the abrasion limit of the nut, improving the specification of a screw nut pair and the like. However, the above methods are generally implemented based on de-rated designs, and although the method can avoid the disadvantage of rapid wear of the nut to some extent, the method increases the material and manufacturing cost of the nut screw transmission device, and wastes resources.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide a nut and screw transmission device which can greatly reduce the abrasion of a working nut, and has simple structure and low cost.

In order to achieve the purpose, the utility model adopts the following technical scheme:

a nut and screw drive comprising:

the lifting nut connecting seat is provided with at least one connecting point, and each connecting point is configured to be connected with a bracket of the car lifting jack;

the rotatable screw rod is movably penetrated through the nut connecting seat;

the working nut is in threaded connection with the lead screw, is connected with the nut connecting seat and forms a first joint and a second joint, a spherical pair or a cylindrical pair is formed at the first joint of the working nut and the nut connecting seat to support the nut connecting seat, and the nut connecting seat can limit the circumferential rotation of the working nut at the second joint;

the resultant moment of the force of the bracket acting on each connecting point on a first point is zero, and the first point is the spherical center of the spherical pair or is positioned on the axis of the cylindrical pair.

Optionally, a first connection point and a second connection point are arranged on the nut connection seat, the first connection point and the second connection point are connected to form a line segment, and the spherical center of the spherical pair is located on the line segment, or the axis of the cylindrical pair is perpendicular to the line segment and intersects with the first point.

Optionally, the nut connecting seat includes barrel and roof, first tie point with the second tie point all sets up on the barrel, the roof sets up the upper end of barrel, the lead screw activity run through in the roof, work nut sets up in the barrel, and with the roof forms first junction.

Optionally, the nut connecting seat further comprises a first connecting rod and a second connecting rod, one end of the first connecting rod and one end of the second connecting rod are respectively arranged on the cylinder, and the other end of the first connecting rod and the other end of the second connecting rod are respectively the first connecting point and the second connecting point.

Optionally, the lead screw and the cylinder are coaxially arranged, the top plate is axisymmetrical along the axis of the cylinder, and the first connecting rod and the second connecting rod are symmetric about the axis of the cylinder;

the spherical center of the spherical pair is positioned on the axis of the lead screw, and the axis of the lead screw is vertical to the line segment, or the axis of the cylindrical pair, the axis of the lead screw and the line segment are vertical to each other in pairs and intersect at the first point.

Optionally, the screw driver further comprises a limiting member, the limiting member is disposed on the nut connecting seat and is connected with the working nut in a relatively slidable manner along a direction parallel to the axis of the screw rod, so as to form the second junction with the working nut.

Optionally, the locating part includes spacing portion and connecting portion that link to each other, connecting portion link firmly on the nut connecting seat, spacing portion with be equipped with first direction arch on one of the two of working nut, be equipped with first direction step on the other, first direction arch with first direction step is along the parallel the axis direction sliding fit of lead screw, and can not rotate relatively.

Optionally, the first guide protrusion is arranged on the limiting part, the first guide step is arranged on the working nut, the nut connecting seat is provided with a second guide step, the first guide step and the second guide step are oppositely arranged to form a limiting guide groove, and the first guide protrusion and the limiting guide groove are in sliding fit along the axis direction of the lead screw and cannot relatively rotate.

Optionally, the working nut comprises a nut cap and a nut body which are connected, the nut cap and the nut connecting seat are connected to form the first joint, and the outer diameter of the nut cap is larger than that of the nut body.

The utility model also aims to provide the car lifting jack, which can greatly reduce the abrasion of the working nut, reduce the material and manufacturing cost of the nut screw transmission device on the car lifting jack and save resources.

the utility model provides a car lifting jack, includes foretell nut screw transmission.

Has the advantages that:

according to the nut and screw transmission device provided by the utility model, the axial position of the screw rod is kept still, the nut connecting seat limits the circumferential rotation of the working nut at the second connecting position, the working nut supports the nut connecting seat at the first connecting position, the nut connecting seat can be driven by the working nut to move relative to the screw rod by rotating the screw rod, so that the position of the nut connecting seat is adjusted, the position of a bracket connected with the nut connecting seat is adjusted, and the loading function of the bracket of the car lifting jack is realized.

When the first connection part is a spherical pair, the resultant moment of force of the bracket acting on each connection point on the spherical center of the spherical pair is zero, when the bracket body shakes, the bracket body can generate unbalance loading torque on the nut connection seat, and because the connection between the nut connection seat and the working nut is the spherical pair, the spherical pair can eliminate the unbalance loading torque on the nut connection seat, so that the bracket body can not act on the working nut, and the working nut can not deflect relative to the screw rod, thereby greatly reducing the abrasion of the connection part of the working nut and the screw rod, prolonging the service life of the bracket body and saving resources.

When first department of meeting is the cylinder pair, the resultant moment of the first point of the power that the bracket acted on each tie point on the axis of cylinder pair is zero, when the bracket body took place to rock, it can produce the unbalance loading moment of torsion to the nut connecting seat, because the connection of nut connecting seat and work nut is the cylinder pair, the cylinder pair can eliminate on the nut connecting seat around the vice axis pivoted unbalance loading moment of torsion of cylinder, make it can not act on the work nut, the work nut can not take place to deflect for the lead screw, thereby the wearing and tearing of work nut and lead screw junction have been alleviateed greatly, the service life is prolonged, and resources are saved.

Drawings

Fig. 1 is a schematic structural view of a nut and screw transmission device provided in an embodiment of the present invention.

In the figure: 1. a nut connecting seat; 11. a barrel; 12. a top plate; 13. a first connecting rod; 14. a second connecting rod; 2. a lead screw; 3. a working nut; 31. a nut cap; 311. a first guide step; 32. a nut body; 4. a limiting member; 41. a limiting part; 411. a first guide projection; 42. a connecting portion.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the utility model and are not limiting of the utility model. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.

In the description of the present invention, unless expressly stated or limited otherwise, the terms "connected," "connected," and "fixed" are to be construed broadly, e.g., as meaning permanently connected, removably connected, or integral to one another; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

In the description of the present embodiment, the terms "upper", "lower", "right", "left", and the like are used based on the orientations and positional relationships shown in the drawings only for convenience of description and simplification of operation, and do not indicate or imply that the referred device or element must have a specific orientation, be configured and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used only for descriptive purposes and are not intended to have a special meaning.

Example one

The present embodiment provides a nut-screw transmission device, as shown in fig. 1, which includes a nut connecting seat 1, a lead screw 2, a working nut 3, and a limiting member 4.

Wherein, be equipped with at least one tie point on the nut connecting seat 1 of liftable, each tie point all is configured to link to each other with the bracket of car lifting jack to on transmitting nut connecting seat 1 with the load of bracket. The rotatable screw rod 2 is movably penetrated through the nut connecting seat 1. The working nut 3 is connected with the nut connecting seat 1, thereby forming a first junction and a second junction. The working nut 3 and the nut connecting seat 1 form a spherical pair at a first joint to support the nut connecting seat 1. The nut attachment seat 1 can restrict circumferential rotation of the working nut 3 at the second junction. The working nut 3 is connected to the screw rod 2 in a threaded manner. The axial position of the screw rod 2 is kept still, the screw rod 2 is rotated due to the limitation of the second junction, the working nut 3 cannot rotate along with the rotation of the screw rod 2, and the screw transmission still occurs between the screw rod 2 and the working nut 3. Therefore, the working nut 3 can drive the nut connecting seat 1 to move relative to the screw rod 2 at the first joint, so that the position of the nut connecting seat 1 is adjusted, the position of the bracket connected with the nut connecting seat 1 is adjusted, and the loading function of the bracket of the car lifting jack is realized.

The resultant moment of the forces acting on the connecting points by the bracket is zero at a first point, which is the center of the sphere of the spherical pair. When the bracket body shakes, the eccentric load torque is applied to the nut connecting seat 1. The connection of the nut connecting seat 1 and the working nut 3 is a spherical pair, and the center of the sphere coincides with the centroid of the eccentric load torque. Therefore, when the screw rod 2 is vertical, the spherical pair can eliminate the unbalance loading torque of the bracket applied on the nut connecting seat 1 around any axis in the horizontal direction, so that the working nut 3 can not deflect relative to the screw rod 2, thereby greatly reducing the abrasion of the joint of the working nut 3 and the screw rod 2, prolonging the service life of the working nut, and saving resources.

Optionally, there are two connection points, which are a first connection point and a second connection point, respectively, the first connection point and the second connection point are connected to form a line segment, and the spherical center of the spherical pair is located on the line segment. The bracket acts on the nut connecting seat 1 through two connecting points, and stress is not easy to concentrate on a single position. The centre of sphere of the spherical pair is located on the line segment, namely the balance point of the resultant moment is located on the line segment, when the bracket shakes, the two connecting points can rotate around the centre of sphere, and then the nut connecting seat 1 is driven to deflect around the centre of sphere relative to the working nut 3, so that the deflection torque is removed, and the working nut 3 is prevented from deflecting relative to the screw rod 2 to damage the threads.

As shown in fig. 1, the nut connecting seat 1 includes a cylinder 11 and a top plate 12, each connecting point is disposed on the cylinder 11, the top plate 12 is disposed at the upper end of the cylinder 11, the screw rod 2 movably penetrates through the top plate 12, and the working nut 3 is disposed in the cylinder 11 and forms a first connection with the top plate 12. Work nut 3 supports nut connecting seat 1 in nut connecting seat 1, has both protected work nut 3 not receive the outer interference of nut connecting seat 1, makes the cooperation stable between nut connecting seat 1 and the work nut 3 again, is difficult for falling the in-process at the carrier and breaking away from each other.

Optionally, the nut connecting seat 1 further includes a first connecting rod 13 and a second connecting rod 14, one end of the first connecting rod 13 and one end of the second connecting rod 14 are respectively disposed on the barrel 11, and the other end of the first connecting rod 13 and the other end of the second connecting rod 14 are respectively a first connecting point and a second connecting point. The first connecting rod 13 and the second connecting rod 14 are simple in structure, convenient to connect and easy to realize moment balance. The load of the bracket is transmitted to the barrel 11 through the first connecting rod 13 and the second connecting rod 14, the first connecting rod 13 and the second connecting rod 14 bear partial load of the bracket respectively, stress is not concentrated, and the structure is not easy to break.

In the present embodiment, the screw 2 and the cylinder 11 are coaxially disposed, the top plate 12 is axisymmetric along the axis of the cylinder 11, and the first connecting rod 13 and the second connecting rod 14 are symmetric about the axis of the cylinder 11. That is to say, nut connecting seat 1 uses lead screw 2 as the symmetrical structure of symmetry axle as one, and when lead screw 2 was vertical, the gravity of nut connecting seat 1 body can not exert the unbalance loading moment of torsion to work nut 3, has alleviateed the wearing and tearing of work nut 3. The sphere center of the spherical pair is positioned on the axis of the screw rod 2, and the axis of the screw rod 2 is vertical to the line segment. That is, the forces of the carriage acting on the two connection points achieve a moment balance on the axis of the spindle 2. When the bracket is at rest, its weight is exerted uniformly downwards on the working nut 3 by the nut connecting socket 1. The stress at each position of the working nut 3 is uniform, and the phenomenon of stress concentration cannot occur at local parts.

In order to limit the rotation of the working nut 3 in the circumferential direction, optionally, the nut-screw transmission device further includes a limiting member 4, and the limiting member 4 is disposed on the nut connecting seat 1 and is connected with the working nut 3 in a relatively slidable manner along the axis direction parallel to the lead screw 2 so as to form a second connection with the working nut 3. The sliding fit between the limiting piece 4 and the working nut 3 solves the problem of mutual motion interference of a first joint and a second joint, so that the nut connecting seat 1 can unload the deflection torque applied by the bracket. Moreover, the rotation of the working nut 3 in the circumferential direction is also limited, so that the height of the nut connecting seat 1 can be conveniently adjusted by rotating the lead screw 2 through the working nut 3.

Optionally, the limiting member 4 includes a limiting portion 41 and a connecting portion 42 connected to each other, the connecting portion 42 is fixedly connected to the nut connecting seat 1, one of the limiting portion 41 and the working nut 3 is provided with a first guiding protrusion 411, the other is provided with a first guiding step 311, and the first guiding protrusion 411 and the first guiding step 311 are in sliding fit along the axis direction of the parallel lead screw 2 and cannot rotate relatively. In this embodiment, the limiting portion 41 is fixed on the connecting portion 42, and the connecting portion 42 is fastened on the nut connecting seat 1 through a bolt, so that the connection is reliable and the disassembly and assembly are convenient.

Further, in this embodiment, the first guide protrusion 411 is disposed on the limiting portion 41, the first guide step 311 is disposed on the working nut 3, the second guide step is disposed on the nut connecting seat 1, the first guide step 311 and the second guide step are disposed oppositely to form a limiting guide groove, and the first guide protrusion 411 and the limiting guide groove are in sliding fit along the axis direction of the parallel lead screw 2 and cannot rotate relatively. The cooperation of increasing second direction step and first direction arch 411 can make nut connecting seat 1 play further limiting displacement to the rotation of working nut 3 in circumference. When the nut and screw driving device is assembled, the alignment condition between the working nut 3 and the nut connecting seat 1 can be accurately judged by observing the alignment of the first guide step 311 and the second guide step.

Alternatively, the working nut 3 comprises a nut cap 31 and a nut body 32 which are connected, the nut cap 31 and the nut connecting seat 1 are connected to form a first joint, and the outer diameter of the nut cap 31 is larger than that of the nut body 32. The outer diameter of the nut cap 31 is larger than that of the nut body 32, so that the contact area of the joint of the nut cap 31 and the nut connecting seat 1 can be increased, and stress concentration is avoided. The nut cap 31 and the nut body 32 are in contact with the screw 2 in the axial direction, and the contact area between the working nut 3 and the screw 2 is large, so that stress concentration can be avoided.

The embodiment also provides a car lifting jack, which comprises the nut and screw transmission device. The abrasion of the working nut 3 on the car lifting jack can be greatly reduced, the material and manufacturing cost of the nut screw transmission device on the car lifting jack is reduced, and resources are saved.

Example two

The present embodiment provides a nut-and-screw transmission device, which is substantially the same as the nut-and-screw transmission device of the first embodiment, and mainly differs therefrom in that the working nut and the nut connecting seat form a cylindrical pair at a first junction, and the first point is located on the axis of the cylindrical pair. When the bracket body shakes, the eccentric load torque can be applied to the nut connecting seat. The connection of the nut connecting seat and the working nut is a cylindrical pair, and the centroid of the unbalance loading torque is on the axis of the cylindrical pair. Therefore, the cylindrical pair can eliminate the unbalance loading torque applied to the nut connecting seat by the bracket around the axis of the cylindrical pair, so that the working nut can not deflect around the axis of the cylindrical pair relative to the lead screw, thereby greatly reducing the abrasion of the joint of the working nut and the lead screw, prolonging the service life of the working nut and saving resources.

Optionally, the axis of the cylindrical pair is perpendicular to the line segment and intersects the first point. When the bracket deflects, the two connecting points rotate around the axis, and then the nut connecting seat is driven to deflect around the axis, so that the deflection torque is removed, and the working nut is prevented from deflecting around the axis of the cylindrical pair in the plane vertical to the axis of the cylindrical pair relative to the screw rod.

Optionally, the axis of the cylindrical pair, the axis of the lead screw, and the line segment are perpendicular to each other two by two and intersect at the first point. When the bracket is static, the gravity of the bracket is uniformly applied to the working nut through the nut connecting seat, the stress at each position of the working nut is uniform, and the phenomenon of local stress concentration between the working nut and the nut connecting seat can not occur.

It should be understood that the above-described embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Numerous obvious variations, adaptations and substitutions will occur to those skilled in the art without departing from the scope of the utility model. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A nut and screw drive, comprising:

the lifting nut connecting seat (1) is provided with at least one connecting point, and each connecting point is configured to be connected with a bracket of the car lifting jack;

the rotatable lead screw (2) is movably penetrated through the nut connecting seat (1);

the working nut (3) is in threaded connection with the lead screw (2), the working nut (3) is connected with the nut connecting seat (1) and forms a first joint and a second joint, a spherical pair or a cylindrical pair is formed at the first joint of the working nut (3) and the nut connecting seat (1) to support the nut connecting seat (1), and the nut connecting seat (1) can limit circumferential rotation of the working nut (3) at the second joint;

2. A nut and screw transmission device according to claim 1, wherein the nut connecting base (1) is provided with a first connecting point and a second connecting point, the first connecting point and the second connecting point are connected to form a line segment, the spherical center of the spherical pair is located on the line segment, or the axis of the cylindrical pair is perpendicular to the line segment and intersects with the first point.

3. The nut and screw transmission device according to claim 2, characterized in that the nut connecting seat (1) comprises a cylinder (11) and a top plate (12), the first connecting point and the second connecting point are both arranged on the cylinder (11), the top plate (12) is arranged at the upper end of the cylinder (11), the screw rod (2) movably penetrates through the top plate (12), and the working nut (3) is arranged in the cylinder (11) and forms the first joint with the top plate (12).

4. A nut and screw transmission according to claim 3, wherein said nut connecting seat (1) further comprises a first connecting rod (13) and a second connecting rod (14), one end of said first connecting rod (13) and one end of said second connecting rod (14) being respectively provided on said cylinder (11), the other end of said first connecting rod (13) and the other end of said second connecting rod (14) being respectively said first connecting point and said second connecting point.

5. A nut-screw transmission according to claim 4, characterized in that the screw (2) and the cylinder (11) are coaxially arranged, the top plate (12) is axisymmetric along the axis of the cylinder (11), and the first connecting rod (13) and the second connecting rod (14) are symmetric about the axis of the cylinder (11);

the sphere center of the spherical pair is positioned on the axis of the lead screw (2), the axis of the lead screw (2) is vertical to the line segment, or the axis of the cylindrical pair, the axis of the lead screw (2) and the line segment are vertical to each other in pairs and intersect at the first point.

6. The nut and screw transmission device according to claim 1, further comprising a limiting member (4), wherein the limiting member (4) is disposed on the nut connecting seat (1) and is connected with the working nut (3) in a manner of being relatively slidable along a direction parallel to the axis of the lead screw (2) so as to form the second junction with the working nut (3).

7. The nut and screw transmission device according to claim 6, characterized in that the limiting member (4) comprises a limiting portion (41) and a connecting portion (42) which are connected, the connecting portion (42) is fixedly connected to the nut connecting seat (1), one of the limiting portion (41) and the working nut (3) is provided with a first guiding protrusion (411), the other one is provided with a first guiding step (311), and the first guiding protrusion (411) and the first guiding step (311) are in sliding fit along the direction parallel to the axis of the lead screw (2) and cannot rotate relatively.

8. The nut and screw transmission device according to claim 7, characterized in that the first guide protrusion (411) is disposed on the limiting portion (41), the first guide step (311) is disposed on the working nut (3), the nut connecting seat (1) is provided with a second guide step, the first guide step (311) and the second guide step are disposed opposite to each other to form a limiting guide groove, and the first guide protrusion (411) and the limiting guide groove are slidably fitted in a direction parallel to the axis of the lead screw (2) and cannot rotate relatively.

9. A nut and screw transmission according to any one of claims 1-8, characterized in that the working nut (3) comprises a nut cap (31) and a nut body (32) connected, the nut cap (31) and the nut coupling seat (1) meeting to form said first meeting point, the outer diameter of the nut cap (31) being larger than the outer diameter of the nut body (32).

10. A car lifting jack, comprising the nut and screw transmission device according to any one of claims 1 to 9.