Driving device and clamp

Abstract

This invention provides a driving device and a clamp. The driving device includes a housing, within which a first chamber and a second chamber are stacked along a first direction. The driving device also includes a transmission mechanism, an output piston, and an elastic element. The transmission mechanism includes multiple wedges, all located in the first chamber and evenly distributed relative to the axis of the output piston. The transmission mechanism also includes a screw threadedly connected to the wedges, and the wedges are slidably connected to a slide rail. The output piston is slidably mounted on the side wall of the second chamber and extends out of the housing. The output piston has an inclined surface or a conical surface corresponding to the wedges, and the output piston is slidably connected to the wedges through the inclined surface or conical surface. The elastic element is located in the second chamber and abuts against the inner side walls of the output piston and the second chamber, respectively. The elastic element applies a force to the output piston close to the first chamber.

Description

Technical Field

[0001] This invention belongs to the field of mechanical clamping technology, and particularly relates to a driving device and clamp. Background Technology

[0002] There are three common types of clamping drive devices for machining: hydraulic drive, pneumatic drive, and manual drive. Hydraulic drive can achieve precise and controllable motion, but the hydraulic system has complex pipelines, is prone to oil leakage, and has high equipment purchase and maintenance costs. Pneumatic drive has a fast response speed and is easy to automate, but it requires an external air source, and the output clamping force is unstable and has a low upper limit. Therefore, the use of hydraulic and pneumatic drive devices is greatly limited in machining scenarios without external oil lines or air sources, as well as in single-piece and small-batch machining applications.

[0003] In existing technologies, although manually driven clamps do not require external power, are low in cost, simple to maintain, and suitable for the aforementioned limited scenarios, ordinary wedge drive structures generally use a single wedge to drive the output piston in order to save costs. When the wedge pushes the output piston, it generates a large lateral force, which can easily cause the wedge to deflect, jam, or wear unevenly, making it difficult to ensure that the output piston only transmits axial force.

[0004] Therefore, there is an urgent need for a driving device and clamp to overcome the above problems. Summary of the Invention

[0005] To address the technical problem mentioned in the background art that a single wedge block driving the output piston will generate a large lateral force, which can easily cause the output piston to deviate, jam, or wear unevenly, making it difficult to ensure that the output piston only transmits axial force, a driving device and fixture are provided.

[0006] To achieve the above objectives, the specific technical solution of the driving device and clamp of the present invention is as follows: A driving device includes a housing, within which a first chamber and a second chamber are arranged in a stacked manner. The driving device further includes: An output piston is slidably mounted on the side wall of the second chamber and extends out of the housing. The output piston is provided with an inclined surface or a conical surface corresponding to the wedge. The output piston is slidably connected to the wedge through the inclined surface or the conical surface. The transmission mechanism includes multiple wedges, all located in the first chamber and evenly distributed relative to the axis of the output piston. The transmission mechanism also includes a screw threadedly connected to the wedges. The wedges and the output piston, as well as the screw and the housing, are in floating fit. The bottom wall of the first chamber is provided with a slide rail corresponding to the number of wedges, and the wedges are slidably connected to the slide rail. An elastic element is located in the second chamber and abuts against the output piston and the inner wall of the second chamber, respectively. The elastic element is used to apply a force to the output piston near the first chamber.

[0007] Furthermore, the transmission mechanism also includes a limiting block, with one end of the screw near the center of the first chamber connected to the limiting block, and the output piston correspondingly provided with a clearance groove, the limiting block being able to extend into the clearance groove to prevent the output piston from contacting the screw.

[0008] Furthermore, there are two screws and two wedges, with the two screws having opposite thread directions and located on both sides of the limiting block, and the screws are connected to the limiting block.

[0009] Furthermore, the drive device also includes a driving gear and a driven gear that can mesh with each other. The driving gear is connected to a power source, and the driven gear is connected to the screw. Both the driving gear and the driven gear are provided with teeth. The driving gear is provided with a concave locking arc, and the driven gear is provided with a convex locking arc. The convex locking arc is adapted to the concave locking arc.

[0010] Furthermore, the concave locking arc is disposed at the tooth tip of the upper gear of the driving gear.

[0011] Furthermore, the screw includes a threaded portion and a smooth portion, the threaded portion being used for threaded connection with the wedge block, and the smooth portion being used for connection with the driven gear.

[0012] Furthermore, a stop block is provided at one end of the slide near the limiting block, the stop block being used to prevent the wedge block from moving excessively.

[0013] Furthermore, the housing is provided with an air supply channel that communicates with the second chamber.

[0014] Furthermore, multiple elastic elements are provided and are arranged circumferentially relative to the center of the output piston.

[0015] A clamp includes grippers and the aforementioned drive mechanism, the grippers being mounted on the end of the output piston, and the drive mechanisms being arranged in pairs to bring the grippers located on different drive mechanisms closer to or further apart from each other.

[0016] The driving device of this invention has the following advantages: By setting multiple sets of relatively centrally symmetrical wedges, these wedges synchronously push against the inclined surface of the output piston. The lateral forces generated by each wedge cancel each other out, solving the problem of large lateral forces in existing single-wedge structures leading to output piston misalignment, jamming, and uneven wear. This ensures the output piston only outputs axial force, resulting in higher motion stability. If any wedge experiences slight misalignment, the floating fit allows for slight adjustment of the screw and wedge, ensuring the output piston remains tightly fitted. Furthermore, the wedges slide along a track at the bottom of the housing, constraining their movement trajectory and ensuring smooth movement, preventing wedge displacement and guaranteeing reliable engagement between the wedges and the inclined surface of the output piston. An elastic element applies a reset force to the output piston. When the wedges retract and release their pushing action on the output piston, the elastic element drives the output piston to automatically return to its original position, achieving the reset function. The first and second chambers are stacked, resulting in a compact structure and reduced overall size of the driving device. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the drive device of the present invention.

[0018] Figure 2 This is a cross-sectional view of the drive device of the present invention.

[0019] Figure 3 This is a schematic diagram of the output piston of the present invention.

[0020] Figure 4 This is a schematic diagram of the housing, transmission mechanism, and driven gear of the present invention.

[0021] Figure 5 This is a schematic diagram of the structure when the driving gear and driven gear of the present invention are meshing.

[0022] Figure 6 This is a schematic diagram of the structure when the driving gear and driven gear of the present invention are locked.

[0023] Explanation of markings in the diagram: 1. Shell; 11. First chamber; 12. Second chamber; 13. Slide rail; 14. Stop block; 15. Gas delivery channel; 2. Transmission mechanism; 211. Screw; 2111. Threaded part; 2112. Smooth part; 212. Wedge block; 22. Limiting block; 3. Output piston; 31. Clearance groove; 32. Inclined surface; 4. Elastic components; 51. Driving gear; 52. Driven gear; 53. Gear teeth; 54. Concave locking arc; 55. Convex locking arc. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] Those skilled in the art will understand that although some embodiments herein include certain features included in other embodiments but not others, combinations of features from different embodiments are intended to be within the scope of the invention and form different embodiments. For example, in the claims, any of the claimed embodiments can be used in any combination.

[0026] 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.

[0027] 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.

[0028] The following is a reference to the appendix. Figure 1 To be continued Figure 6 This invention describes a driving device and a clamp.

[0029] This embodiment provides a driving device, such as... Figures 1-3As shown, the driving device includes a housing 1, within which a first chamber 11 and a second chamber 12 are arranged in a stacked manner. The driving device also includes a transmission mechanism 2, an output piston 3, and an elastic element 4. The output piston 3 is slidably mounted on the side wall of the second chamber 12 and extends out of the housing 1. The output piston 3 is provided with an inclined surface 32 corresponding to the wedge block 212, and the output piston 3 is slidably connected to the wedge block 212 through the inclined surface 32. The transmission mechanism 2 includes multiple wedge blocks 212, and multiple sets of wedge blocks 212 are located in the first chamber 11 and are relative to the output piston. The axes of 3 are evenly distributed. The transmission mechanism 2 also includes a screw 211, which is threadedly connected to a wedge 212. The wedge 212 and the output piston 3, as well as the screw 211 and the housing 1, are in floating fit. The bottom wall of the first chamber 11 is provided with a slide rail 13 corresponding to the number of wedges 212. The wedges 212 are slidably connected to the slide rail 13. The elastic element 4 is located in the second chamber 12 and abuts against the inner sidewalls of the output piston 3 and the second chamber 12 respectively. The elastic element 4 is used to apply a force close to the first chamber 11 to the output piston 3.

[0030] Specifically, the inclined plane 32 mentioned above can also be a conical surface.

[0031] Understandably, by setting multiple sets of relatively centrally symmetrical screws 211 and wedges 212, the multiple wedges 212 synchronously push the inclined surface 32 of the output piston 3, and the lateral component forces generated by each wedge 212 can cancel each other out, solving the problem of the large lateral component force of the existing single wedge 212 structure causing the output piston 3 to deflect, jam, and wear unevenly, ensuring that the output piston 3 only outputs axial force, and has higher motion stability. In use, if any wedge 212 is slightly misaligned, the floating fit setting can allow the screws 211 and wedges 212 to be slightly adjusted, ensuring that the output piston 3 can always be tightly fitted.

[0032] It should be noted that the wedge 212 slides along the slide rail 13 at the bottom of the housing 1, constraining the movement trajectory of the wedge 212 to ensure smooth movement and prevent it from shifting, thus ensuring reliable engagement between the wedge 212 and the inclined surface 32 of the output piston 3. The elastic element 4 applies a reset force to the output piston 3. When the wedge 212 retracts and releases its pushing force on the output piston 3, the elastic element 4 can drive the output piston 3 to automatically return to its original position, achieving the reset function. The first chamber 11 and the second chamber 12 are stacked, resulting in a compact structure and reducing the overall size of the drive device.

[0033] When in use, the screw 211 is connected to the power supply structure, which causes the screw 211 to rotate. The rotation of the screw 211 causes the wedge 212 to move laterally. During the lateral movement of the wedge 212, the output piston 3 moves along the first direction due to the close cooperation between the wedge 212 and the inclined surface 32 of the output piston 3.

[0034] Specifically, the output piston 3 is configured as a piston rod, and its rod and the central hole of the housing 1 have a precise fit of H7 / g6, which makes the center line of the piston rod and the housing 1 highly coincident and has a good central symmetry structure.

[0035] Furthermore, such as Figure 2 and Figure 4 As shown, the transmission mechanism 2 also includes a limiting block 22. One end of the screw 211 near the center of the first chamber 11 is connected to the limiting block 22. The output piston 3 is provided with a relief groove 31. The limiting block 22 can extend into the relief groove 31 to prevent the output piston 3 from contacting the screw 211.

[0036] It should be noted that, through the cooperation of the limiting block 22 and the clearance groove 31, the output piston 3 will not collide or scrape with the screw 211 when it reciprocates and extends, thus avoiding wear on the screw 211 thread by the piston, protecting the threaded transmission pair, and extending the service life of the screw 211 and wedge block 212 threaded pair. In addition, the limiting block 22 can provide support for the inner end of the screw 211, improve the installation stability of the screw 211, reduce radial sway during the rotation of the screw 211, and improve the transmission accuracy.

[0037] Furthermore, such as Figure 3 As shown, there are two screws 211 and two wedges 212. The two screws 211 have opposite thread directions and are located on both sides of the limiting block 22. The screws 211 are connected to the limiting block 22.

[0038] It should be noted that by symmetrically distributing the two sets of screws 211 and wedges 212 in a moderate number, the lateral force can be completely offset without causing structural bulkiness due to excessive components, thus balancing force balance and overall machine miniaturization. The limiting block 22 connects the screws 211 on both sides, providing unified limiting support for the inner ends of the two screws 211, ensuring the coaxiality and installation position accuracy of the two screws 211, and guaranteeing the synchronous movement of the two wedges 212.

[0039] Furthermore, such as Figure 5 and Figure 6 As shown, the drive device also includes a drive gear 51 and a driven gear 52 that can mesh with each other. The drive gear 51 is connected to the power source, and the driven gear 52 is connected to the screw 211. Both the drive gear 51 and the driven gear 52 are provided with gear teeth 53. The drive gear 51 is provided with a concave locking arc 54, and the driven gear 52 is provided with a convex locking arc 55. The convex locking arc 55 and the concave locking arc 54 are adapted to each other.

[0040] It should be noted that the power source transmits power to the screw 211 through a gear pair, realizing the rotational power input, driving the screw 211 to rotate, and in turn driving the wedge block 212 to translate, thus realizing the transmission and amplification of force. The concave locking arc 54 and the convex locking arc 55 cooperate with each other to achieve mechanical locking of the gears after clamping, preventing the gears from rotating under reverse load, realizing the self-locking of the mechanism, maintaining the clamping force without continuous power supply, avoiding the clamping force from loosening, and improving the clamping reliability of the fixture.

[0041] Specifically, the concave locking arc 54 is located at the tip of the tooth 53 on the drive gear 51. Positioning the locking arc at the tooth tip eliminates the need for additional space in the gear hub, simplifying the gear machining structure, facilitating integral machining, and reducing processing costs. The locking arc is integrated with the tooth 53, allowing for rapid engagement after meshing, resulting in timely locking response and precise locking position.

[0042] It should be noted that the driving gear 51 and driven gear 52 provided in this embodiment are a specially designed incomplete gear pair: the driving gear 51 has one or more complete teeth 53, and the space between adjacent teeth 53 is a cylindrical surface; the tip of each tooth 53 of the driven gear 52 has been rounded. In use, when the driving gear 51 rotates, its teeth 53 drive the driven gear 52 to rotate; when it rotates to the self-locking angle position, the cylindrical surface of the driving gear 51 and the rounded tooth surface of the driven gear 52 are in contact. If the driven gear 52 is loaded and has a tendency to rotate in the opposite direction, the cylindrical surface of the driving gear 51 will lock the driven gear 52, preventing it from reversing, thereby achieving reverse self-locking. When the drive device is in the tensioned state, the spring always applies a leftward preload to the piston rod. This preload acts on the driven gear 52 through the wedge block 212 and the lead screw transmission chain, which, together with the above-mentioned gear self-locking, constitutes a two-way self-locking, ensuring that the device will not loosen due to cutting vibration or external impact in the tensioned state.

[0043] Furthermore, such as Figure 4 , Figure 5 and Figure 6 As shown, the screw 211 includes a threaded portion 2111 and a smooth portion 2112. The threaded portion 2111 is used to be threadedly connected to the wedge block 212, and the smooth portion 2112 is used to be connected to the driven gear 52.

[0044] Understandably, the threaded portion 2111 is specifically designed to drive the wedge block 212 to move linearly, while the smooth portion 2112 is used for assembly with the driven gear 52. This prevents thread wear during gear rotation, protecting the threaded pair. The smooth portion 2112 reduces friction at the gear-screw 211 assembly point, resulting in smoother gear rotation and higher power transmission efficiency.

[0045] Furthermore, such as Figure 4As shown, a stop block 14 is provided at one end of the slide 13 near the limit block 22. The stop block 14 is used to prevent the wedge block 212 from moving excessively.

[0046] Understandably, the stop block 14 mechanically limits the inward stroke of the wedge block 212 to prevent it from overtraveling, avoid disengaging from the threaded engagement position, and prevent mechanism failure. By limiting the maximum displacement of the wedge block 212, the maximum extension stroke of the output piston 3 is indirectly limited, preventing the output piston 3 from overtraveling and damaging the elastic element 4 and other components, thus providing overload protection.

[0047] Furthermore, such as Figure 2 As shown, the housing 1 is provided with an air supply channel 15 that communicates with the second chamber 12.

[0048] It is understandable that when the output piston 3 reciprocates in the second chamber 12, the internal volume of the second chamber 12 changes. The air supply channel 15 can realize the flow of gas inside and outside the chamber, balance the air pressure inside the chamber, eliminate the resistance formed by the air pressure inside the chamber during the piston movement, ensure the smooth extension and retraction of the output piston 3, and prevent pressure buildup from causing movement jamming.

[0049] It should be noted that by using a spring as the basic tensioning force source, continuous tensioning can be achieved in the manual self-locking state. Under heavy cutting conditions, external compressed air can be used to pressurize the piston end face, resulting in a greater output tensioning force.

[0050] Furthermore, such as Figure 2 As shown, multiple elastic elements 4 are provided and are arranged circumferentially relative to the center of the output piston 3.

[0051] Understandably, with multiple sets of elastic elements evenly distributed circumferentially, the output piston experiences uniform force at all circumferential positions, preventing skewed torque during reset and further preventing piston jamming, ensuring smooth axial return of the piston. The multiple elastic elements share the load, resulting in a smaller load on a single elastic element and a longer fatigue life.

[0052] This embodiment also provides a clamp, including a gripper and the aforementioned driving device. The gripper is mounted on the end of the output piston 3, and the driving devices are arranged in pairs so that the grippers located on different driving devices move closer or further apart from each other.

[0053] Specifically, using the aforementioned drive device as the power source, it inherits all the advantages of the drive device, such as lateral force cancellation, smooth piston movement, resistance to jamming, and self-locking. The fixture has good clamping stability, stable clamping force, and is not easy to loosen. The drive devices are arranged in pairs, and the two sets of jaws can clamp towards each other or release each other to realize workpiece clamping and release, which is suitable for machining clamping scenarios; no external hydraulic or air source is required, making it suitable for single-piece and small-batch processing scenarios without external energy, and maintenance is simple.

[0054] In this application, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or device. Without further limitation, an element defined by the phrase "comprising..." does not exclude the presence of other identical elements in the article or device that includes said element.

[0055] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0056] 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 can make other variations or modifications based on the above description. 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 driving device, the driving device comprising a housing, wherein a first chamber and a second chamber are disposed therein in a stacked arrangement, characterized in that, The drive device further includes: An output piston is slidably mounted on the side wall of the second chamber and extends out of the housing. The output piston is provided with an inclined surface or a conical surface corresponding to the wedge. The output piston is slidably connected to the wedge through the inclined surface or the conical surface. The transmission mechanism includes multiple wedges, all located in the first chamber and evenly distributed relative to the axis of the output piston. The transmission mechanism also includes a screw threadedly connected to the wedges. The wedges and the output piston, as well as the screw and the housing, are in floating fit. The bottom wall of the first chamber is provided with a slide rail corresponding to the number of wedges, and the wedges are slidably connected to the slide rail. An elastic element is located in the second chamber and abuts against the output piston and the inner wall of the second chamber, respectively. The elastic element is used to apply a force to the output piston near the first chamber.

2. The driving device according to claim 1, characterized in that, The transmission mechanism also includes a limiting block. The end of the screw near the center of the first chamber is connected to the limiting block. The output piston is provided with a corresponding clearance groove. The limiting block can extend into the clearance groove to prevent the output piston from contacting the screw.

3. The driving device according to claim 2, characterized in that, Two screws and two wedges are provided. The two screws have opposite thread directions and are located on both sides of the limiting block. The screws are connected to the limiting block.

4. The driving device according to claim 3, characterized in that, The drive device also includes a drive gear and a driven gear that can mesh with each other. The drive gear is connected to a power source, and the driven gear is connected to the screw. Both the drive gear and the driven gear are provided with teeth. The drive gear is provided with a concave locking arc, and the driven gear is provided with a convex locking arc. The convex locking arc is adapted to the concave locking arc.

5. The driving device according to claim 4, characterized in that, The concave locking arc is located at the tooth tip of the upper gear of the drive gear.

6. The driving device according to claim 4, characterized in that, The screw includes a threaded portion and a smooth portion. The threaded portion is used to connect with the wedge block by a thread, and the smooth portion is used to connect with the driven gear.

7. The driving device according to claim 2, characterized in that, A stop block is provided at one end of the slide near the limiting block, and the stop block is used to prevent the wedge block from moving excessively.

8. The driving device according to claim 1, characterized in that, The housing is provided with a gas supply channel that communicates with the second chamber.

9. The driving device according to claim 1, characterized in that, Multiple elastic elements are provided and are arranged circumferentially relative to the center of the output piston.

10. A clamp, characterized in that, The device includes grippers and a drive mechanism as described in any one of claims 1-9, wherein the grippers are mounted on the end of the output piston, and the drive mechanisms are arranged in pairs such that the grippers located on different drive mechanisms are brought closer to or further away from each other.

Images