A safety nut mechanism and a wheel dolly

Abstract

The present application belongs to the technical field of screw rod transmission, and discloses a safety nut mechanism and a wheel lifting jack. The safety nut mechanism comprises a nut connecting seat, a screw rod, a working nut and a safety assembly. The nut connecting seat is liftable and connected with a bracket of the wheel lifting jack. The rotatable screw rod is movably penetrated in the nut connecting seat. The working nut is arranged on one side of the nut connecting seat and cannot rotate relative to the nut connecting seat, and the working nut is threadedly connected with the screw rod. The safety assembly comprises a safety nut, a connecting assembly and a limiting piece. The safety nut is arranged on the other side of the nut connecting seat and threadedly connected with the screw rod. The limiting piece is used for limiting the rotation of the safety nut. The connecting assembly is used for pressing against the safety nut after the working nut fails. After the working nut fails, the nut connecting seat is pressed against the safety nut through the connecting assembly, and the load transmission is stable. Moreover, the safety nut can replace the working nut to continue the load operation of the wheel lifting jack.

Description

Technical Field

[0001] This invention relates to the field of lead screw transmission technology, and in particular to a safety nut mechanism and a car jacking machine. Background Technology

[0002] When transport vehicles undergo maintenance, they need to be lifted by a lifting machine to allow for the inspection and repair of components under the vehicle. After the inspection and repair are completed, the lifting machine lowers the vehicle back down. Rail vehicle lifting machines generally use a screw and nut drive to raise and lower the support frame. However, using a screw and nut drive has a significant drawback: the working nut wears out quickly, posing a safety hazard to the lifting operation.

[0003] Currently, to prevent the working nut from malfunctioning during the operation of the car-lifting machine, a safety nut is often installed on the lead screw. This safety nut is positioned below the working nut and is connected by a pin or other method to achieve synchronous lifting and lowering movement with the working nut. Over long-term use, the safety nut does not bear the load of the car-lifting machine's support frame. As the working nut wears down, the distance between the car-lifting machine's support frame and the safety nut gradually shortens. When this wear reaches a set limit, a photoelectric sensor is triggered, causing an alarm and stopping the car-lifting operation.

[0004] However, when the working nut unexpectedly collapses, the broken working nut becomes an obstacle between the bracket and the safety nut. Since the broken working nut varies in shape, the load on the bracket cannot be smoothly transferred to the safety nut. This causes the lifting machine to vibrate instantly, potentially severely impacting the vehicle body and posing a significant operational risk. Furthermore, once the bracket rests on the safety nut, the lifting machine can only temporarily maintain stability and loses its lifting or lowering function. If further lowering is required, other emergency measures besides the lifting machine must be taken, which severely impacts production efficiency and operational profitability. Summary of the Invention

[0005] One object of the present invention is to provide a safety nut mechanism in which, after the working nut fails, the load of the bracket can be smoothly transferred to the safety nut, and the safety nut realizes the function of lowering the bracket.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] A safety nut mechanism, comprising:

[0008] The liftable nut connector is configured to connect to the bracket of the car jacking machine;

[0009] A rotatable lead screw extends through the nut connector.

[0010] The working nut is disposed on one side of the nut connecting seat in a manner that prevents relative rotation between the nut connecting seat and the lead screw;

[0011] The safety component includes a safety nut, a connecting component, and a limiting member. The safety nut is disposed on the other side of the nut connecting seat and is threadedly connected to the lead screw. The connecting component and the limiting member are both disposed on the nut connecting seat. The limiting member is connected to the safety nut to restrict the rotation of the safety nut. The connecting component is used to press against the safety nut after the working nut fails.

[0012] Optionally, the connecting assembly includes a first connector, which is fixedly connected to the nut connecting seat. The safety nut is disposed between the first connector and the nut connecting seat along a first direction, which is parallel to the axial direction of the lead screw. The safety nut and the limiting member are slidably connected relative to each other along the first direction. After the working nut fails, the nut connecting seat can drive the first connector to press against the safety nut.

[0013] Optionally, one of the limiting member and the safety nut is provided with a first guide protrusion, and the other is provided with a first guide groove. The first guide protrusion and the first guide groove slide together along the first direction and cannot rotate relative to each other.

[0014] Optionally, one of the limiting member and the nut connecting seat is provided with a second guide protrusion, and the other is provided with a second guide groove. The second guide protrusion and the second guide groove slide in the first direction and cannot rotate relative to each other.

[0015] Optionally, one of the limiting member and the connecting component is provided with a third guide protrusion, and the other is provided with a third guide groove. The third guide protrusion and the third guide groove slide in the first direction and cannot rotate relative to each other.

[0016] Optionally, the limiting member is columnar and is vertically fixed to the nut connecting seat. The safety nut has a guide limiting groove, and the limiting member can be slidably inserted into the guide limiting groove.

[0017] Optionally, the connecting assembly further includes a second connector, which includes a first plate and a second plate. The first plate, the second plate, and the first connector are connected in sequence to form a Z-shaped cross-section, and the first plate is fixedly connected to the nut connector.

[0018] Optionally, the first plate is detachably mounted on the nut connector.

[0019] Optionally, the connecting assembly further includes a bolt, the first plate has a through hole, the nut connector has a threaded hole, and the bolt passes through the through hole and is threaded into the threaded hole.

[0020] Another objective of this invention is to provide a vehicle jacking machine in which, after the working nut fails, the load of the bracket can be smoothly transferred to the safety nut, and the safety nut can replace the working nut to realize the vehicle jacking machine's loading and unloading function.

[0021] To achieve this objective, the present invention adopts the following technical solution:

[0022] A vehicle jacking machine includes the aforementioned safety nut mechanism.

[0023] Beneficial effects:

[0024] The safety nut mechanism and car-lifting machine provided by this invention, before the working nut fails, the working nut is fixed to one side of the nut connecting seat and threadedly connected to the lead screw. The working nut can bear the load of the bracket acting on the nut connecting seat. At the same time, keeping the lead screw in an axial position, rotating the lead screw can also cause the working nut to drive the nut connecting seat to move relative to the lead screw, so as to adjust the position of the nut connecting seat, thereby adjusting the position of the bracket connected to the nut connecting seat, realizing the bracket lowering function of the car-lifting machine.

[0025] After the working nut fails, the nut connector presses against the safety nut via the connecting assembly. The safety nut, on the other side of the nut connector, bears the load exerted by the bracket on the nut connector. Without the obstruction of the working nut between the safety nut and the nut connector, the load transfer is stable, reducing the operational risks caused by the failure of the working nut during the lifting machine's operation. Furthermore, the limiting component restricts the rotation of the safety nut, allowing the nut connector to continue moving relative to the screw by rotating the screw. This enables the safety nut to replace the working nut in adjusting the position of the bracket connected to the nut connector, allowing the lifting machine to continue its lowering operation. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the safety nut mechanism provided in Embodiment 1 of the present invention;

[0027] Figure 2 This is a schematic diagram of the safety nut mechanism provided in Embodiment 2 of the present invention;

[0028] Figure 3 yes Figure 2 View of the middle limit component and safety nut along the AA direction.

[0029] In the diagram: 1. Nut connector; 2. Lead screw; 3. Working nut; 4. Safety component; 41. Safety nut; 411. First guide protrusion; 42. Connecting component; 421. First connector; 422. Second connector; 4221. First plate; 4222. Second plate; 423. Bolt; 43. Limiting component; 431. First guide groove; 432. Second guide protrusion. Detailed Implementation

[0030] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0031] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0032] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0033] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0034] Example 1

[0035] This embodiment provides a safety nut mechanism, such as Figure 1As shown, specifically, it includes a nut connecting seat 1, a lead screw 2, a working nut 3, and a safety component 4. The nut connecting seat 1 is liftable and is configured to connect to the bracket of the car jacking machine. The rotatable lead screw 2 moves through the nut connecting seat 1. The working nut 3 is located on one side of the nut connecting seat 1 and cannot rotate relative to it; the working nut 3 is also threadedly connected to the lead screw 2. Keeping the lead screw 2 stationary in its axial position, the working nut 3 can transfer the load acting on the nut connecting seat 1 by the bracket to the lead screw 2, which then bears the load. Simultaneously, rotating the lead screw 2 allows the working nut 3 to move the nut connecting seat 1 relative to the lead screw 2, thereby adjusting the position of the nut connecting seat 1 and thus adjusting the position of the bracket connected to the nut connecting seat 1, realizing the lowering function of the car jacking machine's bracket.

[0036] Safety component 4 includes a safety nut 41, a connecting component 42, and a limiting component 43. The safety nut 41 is located on the other side of the nut connecting seat 1 and is threadedly connected to the lead screw 2. Both the connecting component 42 and the limiting component 43 are located on the nut connecting seat 1. The limiting component 43 is connected to the safety nut 41 to restrict the rotation of the safety nut 41. The connecting component 42 is used to press against the safety nut 41 after the working nut 3 fails. That is, after the working nut 3 fails, the nut connecting seat 1 presses against the safety nut 41 through the connecting component 42. The safety nut 41, on the other side of the nut connecting seat 1, transfers the load of the bracket acting on the nut connecting seat 1 to the lead screw 2. There is no obstruction between the safety nut 41 and the nut connecting seat 1 by the working nut 3, ensuring stable load transmission and reducing the risk caused by the failure of the working nut 3 during the operation of the lifting machine. Furthermore, the limiting member 43 can restrict the rotation of the safety nut 41, so that the safety nut 41 can continue to move relative to the screw 2 by rotating the screw 2, so that the safety nut 41 can replace the working nut 3 to adjust the position of the bracket and continue the loading and unloading operation of the car lifting machine.

[0037] Optionally, the connecting assembly 42 includes a first connecting member 421, which is fixedly connected to the nut connecting seat 1. A safety nut 41 is disposed between the first connecting member 421 and the nut connecting seat 1 along a first direction parallel to the axial direction of the lead screw 2. The safety nut 41 and the limiting member 43 are slidably connected relative to each other along the first direction. After the working nut 3 fails, the nut connecting seat 1 can drive the first connecting member 421 to press against the safety nut 41. Figure 1As shown, the safety nut 41 is vertically positioned between the first connector 421 and the nut connecting seat 1. When the working nut 3 fails, the weight of the bracket will cause the nut connecting seat 1 to move downwards. The first connector 421 moves downwards with the nut connecting seat 1, thereby pressing against the safety nut 41 and transferring the weight of the bracket to the lead screw 2, reducing the operational risk caused by the failure of the working nut 3 during the operation of the jacking machine. The safety nut 41 and the limiting member 43 are slidably connected relative to each other along the first direction. After the working nut 3 fails, the limiting member 43 will not obstruct the movement of the first connector 421 and the nut connecting seat 1 relative to the working nut 3.

[0038] In this embodiment, the left and right sides of the nut connecting seat 1 are respectively connected to the bracket to support the bracket. The safety nut mechanism includes two connecting components 42, which are arranged on the left and right sides of the nut connecting seat 1 with the lead screw 2 as the axis of symmetry. When the working nut 3 fails, under the action of the bracket, both the left and right sides of the nut connecting seat 1 are subjected to force and move downward. The two connecting components 42 press against the left and right sides of the safety nut 41 respectively, and the left and right sides of the safety nut 41 support the nut connecting seat 1, which can partially balance the off-center torque of the bracket and reduce the wear of the safety nut 41.

[0039] like Figure 1 As shown, the connecting assembly 42 further includes a second connecting member 422, which includes a first plate 4221 and a second plate 4222. The first plate 4221, the second plate 4222, and the first connecting member 421 are connected in sequence to form a Z-shaped cross-section. The first plate 4221 is fixedly connected to the nut connecting seat 1. The Z-shaped structure can confine the safety nut 41 between the first connecting member 421 and the nut connecting seat 1, resulting in a simple structure. In this embodiment, the first connecting member 421, the first plate 4221, and the second plate 4222 are integrally formed steel structures with high structural strength and strong load-bearing capacity.

[0040] To facilitate the assembly of the safety nut 41 onto the safety nut mechanism, the first plate 4221 may optionally be detachably mounted on the nut connecting seat 1. Specifically, the connecting assembly 42 further includes a bolt 423. The first plate 4221 has a through hole, and the nut connecting seat 1 has a threaded hole. The bolt 423 passes through the through hole and is threaded into the threaded hole. The first plate 4221 is fixed to the nut connecting seat 1 by the bolt 423, which facilitates easy assembly and disassembly and ensures a reliable connection.

[0041] In this embodiment, the limiting member 43 is columnar and is vertically fixed to the nut connecting seat 1. A guide limiting groove is provided on the safety nut 41, and the limiting member 43 can be slidably inserted into the guide limiting groove. Figure 1As shown, the limiting member 43 and the guide limiting groove slide together vertically. The cooperation between the two not only avoids the problem of motion interference between the nut connecting seat 1 and the safety nut 41 after the working nut 3 fails, but also restricts the rotation of the safety nut 41 in the circumferential direction, so as to facilitate the height adjustment of the safety nut 41 on the nut connecting seat 1 by rotating the lead screw 2.

[0042] This embodiment also provides a vehicle lifting machine, including the aforementioned safety nut mechanism. In the event of a failure of the working nut 3, the load of the bracket can be smoothly transferred to the safety nut 41, which then replaces the working nut 3 to perform the vehicle lifting machine's lowering function.

[0043] Example 2

[0044] This embodiment provides a safety nut mechanism, which is basically the same as the safety nut mechanism in Embodiment 1. The main difference is that one of the limiting member 43 and the safety nut 41 is provided with a first guide protrusion 411, and the other is provided with a first guide groove 431. The first guide protrusion 411 and the first guide groove 431 slide in a first direction and cannot rotate relative to each other. Figure 2 and Figure 3 As shown, in this embodiment, the limiting member 43 is an annular spline with multiple first guide grooves 431 arranged circumferentially inside it. The safety nut 41 has multiple first guide protrusions 411 on its outer periphery, with each first guide groove 431 corresponding to one of each first guide protrusion 411. By keeping the annular spline fixed circumferentially, the safety nut 41 cannot rotate circumferentially. If the working nut 3 fails, the annular spline and the safety nut 41 can slide relative to each other along the axial direction of the lead screw 2, facilitating the first connecting member 421 to press against the safety nut 41. Compared to the columnar limiting member 43 in Embodiment 1, the annular spline has a limiting effect throughout the entire circumference of the safety nut 41, providing strong torque resistance. In other embodiments, the design positions of the first guide grooves 431 and the first guide protrusions 411 can be interchanged, achieving the same technical effect.

[0045] To restrict the aforementioned annular spline from moving circumferentially, in one embodiment, one of the limiting member 43 and the nut connecting seat 1 is provided with a second guide protrusion 432, and the other is provided with a second guide groove. The second guide protrusion 432 and the second guide groove slide in a first direction and cannot rotate relative to each other. Specifically, a plurality of second guide protrusions 432 are provided circumferentially on the outer periphery of the annular spline, and a groove for accommodating the annular spline is provided on the nut connecting seat 1. The groove wall is provided with a plurality of second guide grooves circumferentially that mate with each of the second guide protrusions 432. When the annular spline is installed in the groove, each second guide groove and each second guide protrusion 432 forms a limit in the circumferential direction of the annular spline, restricting the movement of the annular spline in the circumferential direction. Therefore, when the lead screw 2 rotates, the annular spline, which is circumferentially limited, can effectively restrict the rotation of the safety nut 41 in the circumferential direction. Compared to the columnar limiting member 43 in Embodiment 1, the annular spline is slidably disposed between the nut connecting seat 1 and the safety nut 41, making disassembly and assembly convenient and facilitating the installation and positioning of the safety nut 41 relative to the nut connecting seat 1. Of course, the design positions of the second guide groove and the second guide protrusion 432 can also be interchanged to achieve the same technical effect.

[0046] In another embodiment, one of the limiting member 43 and the connecting component 42 is provided with a third guide protrusion, and the other is provided with a third guide groove. The third guide protrusion and the third guide groove are slidably engaged along the first direction and cannot rotate relative to each other. When assembling the safety nut mechanism, the safety nut 41, the annular spline, and the connecting component 42 are installed in sequence, with the connecting component 42 replacing the nut connecting seat 1 to restrict the circumferential rotation of the annular spline. This facilitates the alignment of the aforementioned guide protrusions and guide grooves, simplifying the installation process. Specifically, the third guide protrusion is the aforementioned second guide protrusion 432, and the third guide groove is disposed on the second plate 4222 along the first direction. Of course, the design positions of the third guide groove and the third guide protrusion can also be interchanged, achieving the same technical effect.

[0047] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art will be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A safety nut mechanism, characterized in that, include: A liftable nut connector (1) is configured to connect to the bracket of the car-lifting machine; A rotatable lead screw (2) extends through the nut connecting seat (1); The working nut (3) is disposed on one side of the nut connecting seat (1) and is not rotatably disposed relative to the nut connecting seat (1), and is threadedly connected to the lead screw (2); Safety component (4) includes safety nut (41), connecting component (42) and limiting component (43). The safety nut (41) is disposed on the other side of the nut connecting seat (1) and threadedly connected to the lead screw (2). The connecting component (42) and the limiting component (43) are both disposed on the nut connecting seat (1). The limiting component (43) is connected to the safety nut (41) to limit the rotation of the safety nut (41). The connecting component (42) is used to press against the safety nut (41) after the working nut (3) fails. The connecting assembly (42) includes a first connector (421), which is fixedly connected to the nut connecting seat (1). The safety nut (41) is disposed between the first connector (421) and the nut connecting seat (1) along a first direction, which is parallel to the axial direction of the lead screw (2). The safety nut (41) and the limiting member (43) are slidably connected relative to each other along the first direction. After the working nut (3) fails, the nut connecting seat (1) can drive the first connector (421) to press against the safety nut (41). One of the limiting member (43) and the safety nut (41) is provided with a first guide protrusion (411), and the other is provided with a first guide groove (431). The first guide protrusion (411) and the first guide groove (431) are slidably engaged along the first direction and cannot rotate relative to each other. The limiting member (43) is columnar and is vertically fixed to the nut connecting seat (1). The safety nut (41) has a guide limiting groove, and the limiting member (43) can be slidably inserted into the guide limiting groove.

2. The safety nut mechanism according to claim 1, characterized in that, One of the limiting member (43) and the nut connecting seat (1) is provided with a second guide protrusion (432), and the other is provided with a second guide groove. The second guide protrusion (432) and the second guide groove slide in the first direction and cannot rotate relative to each other.

3. The safety nut mechanism according to claim 1, characterized in that, One of the limiting member (43) and the connecting component (42) is provided with a third guide protrusion, and the other is provided with a third guide groove. The third guide protrusion and the third guide groove slide together along the first direction and cannot rotate relative to each other.

4. The safety nut mechanism according to any one of claims 1-3, characterized in that, The connecting assembly (42) further includes a second connector (422), which includes a first plate (4221) and a second plate (4222). The first plate (4221), the second plate (4222) and the first connector (421) are connected in sequence to form a Z-shaped structure. The first plate (4221) is fixedly connected to the nut connecting seat (1).

5. The safety nut mechanism according to claim 4, characterized in that, The first plate (4221) is detachably mounted on the nut connector (1).

6. The safety nut mechanism according to claim 5, characterized in that, The connecting assembly (42) further includes a bolt (423), the first plate (4221) has a through hole, the nut connecting seat (1) has a threaded hole, and the bolt (423) passes through the through hole and is threaded into the threaded hole.

7. A vehicle jacking machine, characterized in that, Includes the safety nut mechanism as described in any one of claims 1-6.

Images