Actuator comprising a threaded shaft and a plastic element
The actuator design with a plastic and metal component ensures efficient, compact, and safe operation by integrating a plastic element with a threaded shaft for secure fitting and safety features, addressing efficiency and safety challenges in existing actuators.
Patent Information
- Application Number
- CN201910088792.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Priority Date
- 2018-02-27
- Filing Date
- 2019-01-30
- Publication Date
- 2024-12-31
- Estimated Expiration
- 2039-01-30
AI Technical Summary
Existing actuators face challenges in achieving high efficiency, compact design, ease of manufacturing, and maintaining positional stability during operation, particularly in medical applications where safety shut-off mechanisms are crucial.
An actuator design incorporating a component with a plastic element in contact with a threaded shaft, featuring a metal nut and plastic region, ensures secure fitting and positional stability, allowing for easy assembly and integration of safety features like switch activation or mechanical stop mechanisms.
The design achieves a compact, economical, and reliable actuator with precise positional control, enhancing safety by ensuring accurate shut-off and reducing the risk of accidents through integrated safety mechanisms.
Smart Images
Figure CN110195768B_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to an actuator. Background Art
[0002] An actuator is known which comprises a threaded shaft onto which a nut is screwed. The nut is attached to the threaded shaft using a locking screw. Alternatively, the nut can also be under-dimensioned for the thread of the threaded shaft and comprise a groove. An actuator design is known in which two nuts are screwed onto the threaded shaft such that they are in contact with each other. In addition, Nylstop fixing nuts are also known. Summary of the invention
[0003] The object of the present invention is in particular to achieve high efficiency. This object is creatively achieved by the present invention, while the advantageous designs and further developments of the present invention can be learned from the embodiments of the present invention.
[0004] The invention relates to an actuator comprising a threaded shaft and a component comprising an internal thread screwed onto the threaded shaft.
[0005] It is proposed that the component comprises at least one region which consists of plastic, in particular hard plastic, and which is in contact with the threaded shaft. According to the invention, a high efficiency is achieved. In particular, a very compact, very economical and easy to manufacture design can be achieved. Furthermore, it can be achieved in particular that the component can be screwed onto the threaded shaft in a simple manner and nevertheless maintains its position relative to the threaded shaft during operation of the actuator. In particular, the component can function as a safety end stop as defined in the IEC 60601-1 standard.
[0006] Further advantages are derived from the following description of the drawings. In the drawings, exemplary embodiments of the invention are depicted. The drawings, the description and the claims contain many combined features. A person skilled in the art will also advantageously consider these features individually and combine them into more meaningful combinations. BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Figure 1 A perspective view showing components of the present invention,
[0008] Figure 2 The cross section of the component is shown so that it is divided in half,
[0009] Figure 3 The metal components of the component are shown, and
[0010] Figure 4 The plastic elements of the component are shown. DETAILED DESCRIPTION
[0011] Figure 1 and 2 The component of the invention is shown, which in the mounted state is screwed onto a threaded shaft of an actuator, in particular a lifting actuator. The component comprises a metal element 16 configured as a nut 26 and a plastic element 18. In the mounted state, the internal thread of the nut 26 is screwed onto the threaded shaft. The plastic element 18 comprises a region 14 which is in contact with the threaded shaft in the mounted state. The region 14 is annular. In the state in which the component is removed from the threaded shaft, the region 14 is deformed compared to the state in which the component is screwed onto the threaded shaft. In cross section ( Figure 2 ), which area is configured in the shape of a lip. On its radially outer area, the metal element 16 comprises gear teeth extending over the entire circumference of the metal element 16. The metal element 16 is pressed into the base material element.
[0012] By screwing the component onto the threaded shaft, the nut is rotated about the central axis 28. The distance of the region 14 from the central axis is smaller than the outer diameter 30 of the internal thread 12 of the nut 26. The plastic element 18 is in contact with more than 10% of the total surface of the metal element with its surface.
[0013] On its radially outer surface, the plastic element comprises a flat area 32 which can be gripped by a wrench, so that by moving the wrench the component can be screwed onto the threaded shaft. Here, the plastic element 18 transfers the force in the circumferential direction 20 to the metal element 16. The axial side end surface 22 ( Figure 2 ) is further away from the center of gravity of the component than the axial side end surface 24 of the plastic element, wherein the two end surfaces are arranged on the same side of the component. This has the advantage that the plastic element is not pressed away from the metal element by pressing the corresponding side of the component onto the flat surface of the housing.
[0014] Area 14 ensures that the position of the component is fixed relative to the threaded shaft during operation of the actuator. Furthermore, the component is used to realize the switching off of the drive of the actuator, in particular by the component actuating a switch when the component reaches its specific position relative to the housing of the actuator; the switch deactivates the drive. If the switch fails, the component causes the threaded shaft to stop mechanically relative to the housing of the actuator, which is particularly important for medical actuators, since there are two shut-off mechanisms here. By tightening the component, the end position of both shut-off mechanisms is changed simultaneously, which reduces the risk of accidents at the operating table in particular.
[0015] Instead of the mentioned switch, the end position of the threaded shaft can also be marked by pressing a component of the housing of the actuator, thereby generating an overcurrent in the actuator which signals the actuator electronics that the end position has been reached, which end position is then stored in the actuator's memory.
[0016] Screw a component onto the first end of the threaded shaft. Screw another identical component onto the second end of the threaded shaft. By tightening the two components on the threaded shaft, the maximum and minimum positions of the actuator as well as the total stroke of the actuator can be adjusted very accurately, which is particularly useful for compensating tolerances.
[0017] In the present case, the nut 26 is relatively short, which saves installation space.
[0018] When the component is screwed onto the threaded shaft, the plastic component and the metal component are held in place relative to each other by the threads of the threaded shaft. When the component is screwed onto the threaded shaft, a special tool is used to ensure that the plastic component and the metal component are held in place relative to each other.
[0019] Since both metal and plastic components are very cost-effective, the entire component is also very cost-effective.
[0020] The plastic element may consist of hard plastic.
[0021] Reference numerals list
[0022] 10 parts
[0023] 12 Internal thread
[0024] 14 Area
[0025] 16Metal components
[0026] 18 Plastic components
[0027] 20 Circumferential direction
[0028] 22 end surface
[0029] 24 end surface
[0030] 26 Nut
[0031] 28Central axis
[0032] 30 outer diameter
[0033] 32 Flat Area
Claims
1. An actuator comprising a housing, a threaded shaft, a driver configured to move the threaded shaft relative to the housing during operation of the actuator, and a component (10) comprising an internal thread (12) and being screwed onto the threaded shaft, The component comprises at least one plastic element (18) and at least one metal element (16), wherein: - the plastic element (18) is in contact with the metal element (16) and comprises at least one region (14) which is made of plastic and is in contact with the threaded shaft, and - the metal element (16) is configured to transmit an interference fit and / or friction fit force to the plastic element (18) in the circumferential direction, Therein, the region (14) ensures that the position of the component is fixed relative to the threaded shaft during operation of the actuator.
2. The actuator according to claim 1, wherein: The plastic element is configured so as to be able to transmit force to the metal element in a circumferential direction (20) of the metal element in an interference fit manner.
3. The actuator according to any one of claims 1 or 2, wherein: The metal element is pressed into the plastic element, or the plastic element is produced by partial overmolding of the metal element.
4. The actuator according to claim 1, wherein: The axial side end surface (22) of the metal element is further away from the center of gravity of the component than the axial side end surface (24) of the plastic element, and the plastic element is arranged on the same side of the component as the axial side end surface of the metal element.
5. The actuator according to claim 1, wherein: The region is deformed compared to a state in which the component is removed from the threaded shaft.
6. The actuator according to claim 1, wherein: The area is configured in a lip shape.
7. The actuator according to claim 1, wherein: The components can be screwed onto the threaded shaft using a wrench.
8. The actuator according to claim 1, wherein: The plastic element contacts at least 10% of the total surface of the nut.
9. A component (10) for an actuator, the actuator comprising a housing, a threaded shaft, a driver configured to move the threaded shaft relative to the housing during operation of the actuator, the component (10) comprising an internal thread (12) for screwing the component (10) onto the threaded shaft, the component (10) comprising at least one plastic element (18) and at least one metal element (16), wherein: - the plastic element (18) is in contact with the metal element (16) and comprises at least one region (14) which is made of plastic and is in contact with the threaded shaft, - the metal element (16) is configured to transmit an interference fit and / or friction fit force to the plastic element (18) in the circumferential direction, and - This area (14) ensures that the position of the component (10) is fixed relative to the threaded shaft during operation of the actuator.