Reverse transmission locking and overload protection double-acting mechanism and electric cylinder

Abstract

The invention discloses a reverse transmission locking and overload protection double-acting mechanism and an electric cylinder. The double-acting mechanism comprises a first shaft sleeve, a second shaft sleeve and a third shaft sleeve, the transmission wheel is movably arranged on the first shaft sleeve in a sleeving manner; the groove plates are oppositely and fixedly mounted on the transmission wheel in the circumferential direction and are provided with grooves for placing the balls; the retainer is mounted on the first shaft sleeve in a torque transmission connection manner and is provided with a first mounting hole for accommodating the ball; the convex sleeve is installed on the first shaft sleeve in a torque transmission connection mode, the first end of the convex sleeve is in direct or indirect contact connection with the balls, and a convex structure is arranged at the second end of the convex sleeve; the taper sleeve is connected to the lead screw shaft through a key, the small end of the taper sleeve is provided with a groove structure matched with the protruding structure, and the taper sleeve is provided with an outer conical surface; the sleeve is relatively and fixedly connected with the shell of the electric cylinder and is provided with an inner conical surface matched with the outer conical surface of the conical sleeve; one end of the compression elastic piece is pressed on the limiting end face fixed relative to the lead screw shaft, and the other end of the compression elastic piece abuts against the large-head end face of the taper sleeve.

Description

Technical Field

[0001] The invention belongs to the technical field of electric cylinders and relates to a reverse transmission locking and overload protection double-acting mechanism and an electric cylinder. Background Art

[0002] The electric cylinder is a driving device that converts the rotational motion of the motor into linear motion. Its basic principle is to convert the motor drive through deceleration or directly drive the ball screw pair to perform motion conversion. In this process, the precise speed control and other characteristics of the motor are converted into precise speed and position control, thereby achieving high-precision linear motion. Due to its unique performance and advantages, it is widely used in many fields, including but not limited to industrial automation, medical equipment, testing equipment, etc.

[0003] In the application of electric cylinders, preventing reverse transmission caused by external forces is the key to ensuring system stability and safety. The reverse transmission locking mechanism can prevent the output components of the electric cylinder from moving in the opposite direction due to external forces when the power is off or the load changes suddenly, thereby protecting the safety of equipment and personnel. In addition, the electric cylinder may encounter a load that exceeds its design during operation, which may cause the motor to overheat, damage, or even cause a safety accident. The overload protection mechanism is an integral part of the design of the electric cylinder.

[0004] In addition to the basic transmission function, electric cylinders are also required to have higher precision, stronger stability and more complete safety protection mechanisms in various application scenarios. Therefore, integrating advanced technologies such as reverse transmission locking and overload protection into electric cylinders has become one of the important directions for the development of electric cylinder technology.

[0005] In the existing technical solutions, the reverse transmission lock and overload protection are each independent mechanisms, and can only be arranged in a structural manner by connecting two assemblies when used in the electric cylinder. The two functions cannot be directly and effectively integrated into one assembly, resulting in a larger installation space required, which is not suitable for the arrangement of electric cylinders in compact spaces. Summary of the invention

[0006] Purpose: In view of at least one of the above technical problems, the present invention provides a reverse transmission locking and overload protection double-acting mechanism and an electric cylinder. The reverse transmission locking and overload protection functions are integrated and applied to the electric cylinder, so as to realize the input end opening and output end locking and limit the torque of the transmission system, reduce the space required for the mechanism, further improve the integration of the electric cylinder, and be more conducive to the installation and use of the electric cylinder in a compact space.

[0007] Technical solution: To solve the above technical problems, the technical solution adopted by the present invention is: In a first aspect, a reverse transmission locking and overload protection dual-acting mechanism is provided, comprising: First bushing; A transmission wheel, which is transmission-connected to the power output end of the motor, and is movably sleeved on the first shaft sleeve; The groove plate is relatively fixedly mounted on the transmission wheel in the circumferential direction and is provided with grooves for accommodating the balls; A retainer, which is connected to the first sleeve for torque transmission, is provided with a first mounting hole for accommodating a ball, and the inner diameter of the first mounting hole is larger than the diameter of the ball; A convex sleeve is installed on the first sleeve in a torque transmission connection, and a first end of the convex sleeve is directly or indirectly in contact with the ball, and a second end of the convex sleeve is provided with a convex structure; A cone sleeve is connected to the screw shaft through a key, the small end of the cone sleeve is provided with a groove structure matching with the protrusion structure, and the cone sleeve is provided with an outer cone surface; A sleeve is relatively fixedly connected to the housing of the electric cylinder and is located outside the cone sleeve. It is provided with an inner cone surface that matches the outer cone surface of the cone sleeve. The minimum inner hole diameter of the sleeve is smaller than the maximum outer diameter of the cone sleeve, and the maximum inner hole diameter of the sleeve is larger than the maximum outer diameter of the cone sleeve. A compression elastic member, one end of which is pressed on a limiting end face fixed relatively to the screw shaft, and the other end of which is abutted against the large end face of the tapered sleeve; and under the thrust of the compression elastic member, the tapered sleeve moves axially toward the convex sleeve, so that the outer conical surface of the tapered sleeve contacts the inner conical surface of the sleeve to generate a locking friction torque, and pushes the convex sleeve to press the ball into the groove of the groove plate for transmitting torque.

[0008] In some embodiments, in the reverse transmission locking and overload protection dual-acting mechanism, in the reverse transmission state, the transmission wheel does not provide torque, and the convex sleeve passively follows the tapered sleeve and cannot provide thrust to push the tapered sleeve out of the sleeve. Therefore, the locking friction torque provided by the sleeve always exists, and the outer cone surface of the tapered sleeve and the inner cone surface of the sleeve are always in a locked state, resulting in the inability to reversely transmit the torque and rotation of the screw shaft, thereby realizing reverse transmission mechanical locking.

[0009] In some embodiments, the reverse transmission locking and overload protection double-acting mechanism, in the positive transmission state, the transmission wheel provides torque, which is transmitted to the convex sleeve through the groove plate, the ball, the retaining frame, and the first sleeve in sequence, and the convex structure of the convex sleeve is pressed into the groove structure of the tapered sleeve. The rotation of the convex sleeve squeezes the tapered sleeve through the convex structure, causing the tapered sleeve to separate from the sleeve. At this time, the locking friction torque provided by the sleeve disappears, and the torque can be transmitted to the screw shaft through the tapered sleeve and the key.

[0010] Furthermore, when the torque exceeds the set value, the compression elastic member continues to be compressed, the ball rolls out of the groove and slips, and separates from the groove plate. At this time, the first sleeve stops rotating, thereby achieving overload protection.

[0011] In some embodiments, a circumferential limit mounting structure is provided at one end of the transmission wheel near the groove plate, and a second mounting hole matching the circumferential limit mounting structure is provided at the center of the groove plate. The second mounting hole of the groove plate is connected to the circumferential limit mounting structure of the transmission wheel, so that the groove plate and the transmission wheel are fixed in the circumferential direction and can transmit torque.

[0012] In some embodiments, a first mounting structure is disposed on the first sleeve; A second mounting structure matching the first mounting structure is provided at the center of the retainer, and the second mounting structure of the retainer is connected to the first mounting structure of the first sleeve for transmitting torque; A third mounting structure matching with the first mounting structure is provided at the center of the convex sleeve, and the third mounting structure of the convex sleeve is connected to the first mounting structure of the first shaft sleeve for transmitting torque.

[0013] In some embodiments, the reverse transmission locking and overload protection dual-acting mechanism further includes a pressure plate, which is disposed between the convex sleeve and the ball located in the retaining frame to prevent the ball from wearing the convex sleeve.

[0014] In some embodiments, the reverse transmission locking and overload protection dual-acting mechanism further includes a gasket, which is disposed between the transmission wheel and the first sleeve to prevent direct wear between the transmission wheel and the first sleeve.

[0015] In some embodiments, the reverse transmission locking and overload protection dual-acting mechanism is characterized in that a limit member is also provided at the end of the first sleeve away from the cone sleeve to provide a reaction force to resist the pressure of the compression elastic member.

[0016] In some embodiments, the compression elastic member is a compression spring.

[0017] In some embodiments, the key connection is a flat key connection, a semicircular key connection, a wedge key connection or a tangential key connection.

[0018] In some embodiments, the protrusion structure is a V-shaped cone protrusion structure; and the groove structure is a V-shaped groove structure matched with the V-shaped cone protrusion structure.

[0019] In some embodiments, the convex sleeve and the conical sleeve are arranged coaxially.

[0020] In a second aspect, an electric cylinder is provided, comprising the reverse transmission locking and overload protection dual-acting mechanism.

[0021] In some embodiments, the electric cylinder also includes a motor, a transmission mechanism, a screw nut, and a piston rod; the power output end of the motor is connected to the transmission wheel through the transmission mechanism, the screw shaft spirally transmits the screw nut, and the screw nut is connected to the piston rod for converting rotational motion into linear motion of the piston rod.

[0022] Beneficial effects: The reverse transmission locking and overload protection double-acting mechanism and electric cylinder provided by the present invention have the following advantages: the reverse transmission locking and overload protection functions are integrated in the same mechanism and applied to the electric cylinder. A compression spring is used to compress the outer cone surface of the cone sleeve and the inner cone surface of the sleeve to generate a braking torque. The convex structure of the convex sleeve and the groove structure of the cone sleeve cooperate to counteract the compression force of the spring by rotating the convex sleeve to lock and open. The sleeve and the housing are fixedly connected; a compression spring is used to press the ball into the groove plate, and torque transmission and overload protection are performed through the installation structure between the transmission wheel, the groove plate, the retaining frame, and the shaft sleeve; the input end is opened, the output end is locked, and the torque of the transmission system is limited. The reverse transmission locking function and the overload protection function use the same elastic element, which reduces the required space of the mechanism, further improves the integration of the electric cylinder, and is more conducive to the installation and use of the electric cylinder in a compact space. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a structural schematic diagram of a reverse transmission locking and overload protection double-acting mechanism according to an embodiment of the present invention; Figure 2 Schematic diagram of the assembly relationship of the reverse transmission locking and overload protection double-acting mechanism according to one embodiment of the present invention; Figure 3 is a schematic structural diagram of a convex sleeve according to an embodiment of the present invention; Figure 4 is a schematic structural diagram of a convex sleeve according to an embodiment of the present invention; Figure 5 Schematic diagram of the working relationship between the convex sleeve and the conical sleeve according to one embodiment of the present invention; Figure 6 A schematic diagram of the structure of an electric cylinder having a reverse transmission locking and overload protection dual-acting mechanism according to an embodiment of the present invention; In the figure: screw shaft 1, compression elastic member 2, tapered sleeve 3, outer cone 3a, groove structure 3b, sleeve 5, inner cone 5a, convex sleeve 6, convex structure 6a, annular plate structure 6b, third mounting structure 6c, pressure plate 7, ball 8, retaining frame 9, first mounting hole 9a, second mounting structure 9b, groove plate 10, second mounting hole 10a, groove 10b, transmission wheel 11, circumferential limit mounting structure 11a, gasket 12, first sleeve 13, first mounting structure 13a, transmission wheel mounting portion 13b, limit nut 14, transmission mechanism 15, reverse transmission locking and overload protection double-acting mechanism 16, housing 17, second sleeve 18, bearing 19, screw nut 20, cylinder body 21, piston rod 22, motor 23. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values ​​of the parts and steps set forth in these embodiments do not limit the scope of the present invention. Meanwhile, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be considered as a part of the specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, and therefore, once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0026] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", etc. are used only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present application, unless otherwise specified, "multiple" means two or more.

[0027] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood by specific circumstances.

[0028] Example 1: Figure 1 , Figure 2 As shown, a reverse transmission locking and overload protection dual-acting mechanism comprises: A first sleeve 13; The transmission wheel 11 is transmission-connected to the power output end of the motor and is movably sleeved on the first shaft sleeve 13; The groove plate 10 is relatively fixedly mounted on the transmission wheel 11 in the circumferential direction and is provided with a groove 10b for accommodating the ball 8; A retainer 9 is connected and mounted on the first sleeve 13 in a torque transmission manner, and is provided with a first mounting hole 9a for accommodating the ball 8, and the inner diameter of the first mounting hole 9a is larger than the diameter of the ball 8; A convex sleeve 6 is connected and mounted on the first shaft sleeve 13 for torque transmission, and a first end of the convex sleeve is directly or indirectly in contact with the ball 8, and a convex structure is provided at a second end of the convex sleeve; A cone sleeve 3 is connected to the screw shaft 1 through a key, the small end of the cone sleeve is provided with a groove structure matching with the protrusion structure, and the cone sleeve is provided with an outer cone surface; The sleeve 5 is relatively fixedly connected to the housing of the electric cylinder and is located outside the cone sleeve. It is provided with an inner cone surface matching the outer cone surface of the cone sleeve. The minimum inner hole diameter of the sleeve is smaller than the maximum outer diameter of the cone sleeve, and the maximum inner hole diameter of the sleeve is larger than the maximum outer diameter of the cone sleeve. The compression elastic member 2 has one end pressed on a limiting end face fixed relatively to the screw shaft, and the other end abuts against the large end face of the tapered sleeve; and under the thrust of the compression elastic member, the tapered sleeve moves axially toward the convex sleeve, so that the outer conical surface of the tapered sleeve contacts the inner conical surface of the sleeve to generate a locking friction torque, and pushes the convex sleeve to press the ball 8 into the groove 10b of the groove plate 10 for transmitting torque.

[0029] The reverse transmission locking and overload protection dual-acting mechanism described in the embodiment of the present application, in the reverse transmission state (power is transmitted from the screw shaft to the motor shaft), the transmission wheel does not provide torque, the convex sleeve passively follows the tapered sleeve and cannot provide thrust to push the tapered sleeve out of the sleeve. Therefore, the locking friction torque provided by the sleeve always exists, and the outer cone surface of the tapered sleeve and the inner cone surface of the sleeve are always in a locked state, resulting in the inability to reversely transmit the torque and rotation of the screw shaft, thereby realizing reverse transmission mechanical locking.

[0030] The reverse transmission locking and overload protection double-acting mechanism described in the embodiment of the present application, in the positive transmission state (power is transmitted from the motor shaft to the screw shaft), the transmission wheel 11 provides torque, which is transmitted to the convex sleeve 6 through the groove plate 10, the ball 8, the retaining frame 9, and the first sleeve 13 in sequence. The convex structure of the convex sleeve is pressed into the groove structure of the tapered sleeve. The rotation of the convex sleeve squeezes the tapered sleeve through the convex structure, causing the tapered sleeve to separate from the sleeve. At this time, the locking friction torque provided by the sleeve disappears, and the torque can be transmitted to the screw shaft through the tapered sleeve and the key.

[0031] When the torque exceeds the set value, the compression elastic member 2 continues to be compressed, and the ball 8 rolls out of the groove 10b and slips, and separates from the groove plate 10. At this time, the first sleeve 13 stops rotating, achieving overload protection.

[0032] In some embodiments, a circumferential limiting mounting structure 11a is provided at one end of the transmission wheel 11 near the groove plate 10, and a second mounting hole 10a matching the circumferential limiting mounting structure 11a is provided at the center of the groove plate 10. The second mounting hole 10a of the groove plate 10 and the circumferential limiting mounting structure 11a of the transmission wheel 11 are connected, so that the groove plate 10 and the transmission wheel 11 are fixed in the circumferential direction and can transmit torque.

[0033] In some embodiments, a first mounting structure 13a is provided on the first sleeve 13; A second mounting structure 9b matching the first mounting structure 13a is provided at the center of the retainer 9, and the second mounting structure 9b of the retainer 9 is connected to the first mounting structure 13a of the first sleeve 13 for transmitting torque; A third mounting structure 6c matching with the first mounting structure 13a is provided at the center of the convex sleeve 6. The third mounting structure 6c of the convex sleeve 6 is connected to the first mounting structure 13a of the first shaft sleeve 13 for transmitting torque.

[0034] In this embodiment, Figure 2 As shown, the outer periphery of the first sleeve 13 is provided with a first mounting structure 13a and a transmission wheel mounting portion 13b, the first mounting structure 13a is used to cooperate with the mounting of the retainer 9 and the convex sleeve 6; the transmission wheel mounting portion 13b is used to support the transmission wheel 11 and to axially limit the transmission wheel 11. In this embodiment, the first mounting structure 13a of the first sleeve 13 is set as a flat key structure, and the step structure formed with the transmission wheel mounting portion 13b can realize the axial limiting function of the retainer 9.

[0035] In some embodiments, the reverse transmission locking and overload protection dual-acting mechanism further includes a pressure plate 7, which is arranged between the convex sleeve 6 and the ball 8 located in the retaining frame 9 to prevent the ball 8 from wearing the convex sleeve 6.

[0036] In some embodiments, Figure 2 , Figure 4 As shown, the first end of the convex sleeve 6 is set as an annular plate structure 6b, which is convenient for pressing the ball 8 into the groove 10b of the groove plate 10; or the annular plate structure 6b pushes the pressing plate 7 to press the ball 8 into the groove 10b of the groove plate 10. In this embodiment, the groove plate 10 has tapered grooves 10b uniformly distributed in the circumference, corresponding to the first mounting hole 9a of the retainer 9. The ball 8 is pressed into the tapered groove 10b at one end under the thrust of the left annular plate structure 6b. In addition, the tapered groove 10b is conducive to the ball 8 sliding out of the groove 10b during overload protection.

[0037] In some embodiments, the reverse transmission locking and overload protection dual-acting mechanism further includes a gasket 12 disposed between the transmission wheel 11 and the first shaft sleeve 13 to prevent direct wear of the transmission wheel 11 and the first shaft sleeve 13 .

[0038] In some embodiments, a limiting member is further provided at one end of the first sleeve 13 away from the cone sleeve 3 to provide a reaction force to resist the pressure of the compression elastic member 2. In this embodiment, the limiting member is a limiting nut 14.

[0039] In some embodiments, the compression elastic member 2 is a compression spring.

[0040] In some embodiments, the key connection adopts a flat key connection, a semicircular key connection, a wedge key connection or a tangential key connection. In this embodiment, the key connection adopts a flat key connection.

[0041] In some embodiments, Figure 3 , Figure 5 As shown, the protrusion structure is a V-shaped cone protrusion structure, and the groove structure is a V-shaped groove structure matched with the V-shaped cone protrusion structure.

[0042] In some embodiments, the convex sleeve and the tapered sleeve are coaxially arranged. More preferably, in this embodiment, the convex sleeve 6, the tapered sleeve 3 and the screw shaft 1 are coaxially arranged.

[0043] In some embodiments, Figures 1 to 5 As shown, a reverse transmission locking and overload protection double-acting mechanism 16 includes a compression elastic member 2, a cone sleeve 3, a sleeve 5, a convex sleeve 6, a pressure plate 7, a ball 8, a retainer 9, a groove plate 10, a transmission wheel 11, a gasket 12, a first shaft sleeve 13, and a limit nut 14; The screw shaft 1 of the electric cylinder is installed on the cylinder body 21 of the electric cylinder via the second sleeve 18 and the bearing 19; The first sleeve 13 is movably mounted on the screw shaft 1; The transmission wheel 11 is transmission-connected to the power output end of the motor and is movably sleeved on the first shaft sleeve 13; The groove plate 10 is relatively fixedly mounted on the transmission wheel 11 in the circumferential direction, and the second mounting hole 10a of the groove plate 10 is connected to the circumferential limit mounting structure 11a of the transmission wheel, so that the groove plate 10 and the transmission wheel 11 are fixed in the circumferential direction and can transmit torque; the groove plate 10 is provided with a groove 10b for accommodating the ball 8, the ball 8 is placed in the first mounting hole 9a of the retainer 9, and the ball 9 is pressed into the groove 10b of the groove plate 10 by the pressure plate 7 located at the first end of the convex sleeve 6; The retainer 9 is connected and mounted on the first sleeve 13 for torque transmission, and is provided with a first mounting hole 9a for accommodating the ball 8, and the inner diameter of the first mounting hole 9a is larger than the diameter of the ball 8; the second mounting structure 9b of the retainer 9 is connected to the first mounting structure 13a of the first sleeve 13 for torque transmission; The convex sleeve 6 is connected and mounted on the first sleeve 13 for torque transmission, and the first end of the convex sleeve is directly or indirectly in contact with the ball 8, and the second end of the convex sleeve is provided with a convex structure 6a; the third mounting structure 6c of the inner hole of the convex sleeve 6 is matched and connected with the first mounting structure 13a of the first sleeve 13 for transmitting torque; The tapered sleeve 3 is connected to the screw shaft 1 through a flat key 4, the small end of the tapered sleeve is provided with a groove structure 3b matched with the protruding structure 6a, and the tapered sleeve is provided with an outer tapered surface 3a; The sleeve 5 is relatively fixedly connected to the housing 17 of the electric cylinder and is located outside the cone sleeve 3. It is provided with an inner cone surface 5a matching the outer cone surface 3a of the cone sleeve. The minimum inner hole diameter of the sleeve is smaller than the maximum outer diameter of the cone sleeve, and the maximum inner hole diameter of the sleeve is larger than the maximum outer diameter of the cone sleeve. The compression elastic member 2 has one end pressed on the step end face of the screw shaft 1 and the end face of the second sleeve 18, and the other end abuts against the large end face of the tapered sleeve 3; and under the thrust of the compression elastic member 2, the tapered sleeve moves axially toward the convex sleeve, so that the outer conical surface of the tapered sleeve contacts the inner conical surface of the sleeve to generate a locking friction torque, and pushes the convex sleeve to press the ball 8 into the groove 10b of the groove plate 10 for transmitting torque; The limiting nut 14 is arranged at one end of the first sleeve 13 away from the tapered sleeve 3 , and is used to provide a reaction force to resist the pressure of the compression elastic member 2 .

[0044] The torque output by the motor 23 is transmitted to the convex sleeve 6 through the transmission mechanism 15, the transmission wheel 11, the groove plate 10, the ball 8, the retainer 9, and the first sleeve 13, and then transmitted to the screw shaft 1 through the taper sleeve 3 and the flat key 4, driving the screw nut 20 and the piston rod 22 connected to the screw nut 20 to complete the linear motion of the electric cylinder. When the torque exceeds the set value (limit torque), the compression elastic member 2 continues to be compressed, the ball 8 rolls out of the groove 10b and slips, and detaches from the groove plate 10, and the first sleeve 13 stops rotating.

[0045] In this application, the reverse transmission locking and overload protection double-acting mechanism integrates the reverse transmission locking and overload protection functions in the same mechanism and is applied to the electric cylinder. A compression spring is used to compress the outer cone surface of the cone sleeve and the inner cone surface of the sleeve to generate a braking torque. The convex structure of the convex sleeve and the groove structure of the cone sleeve cooperate to counteract the spring compression force through the rotation of the convex sleeve to lock and open, and the sleeve and the housing are fixedly connected; a compression spring is used to press the ball into the groove plate, and torque transmission and overload protection are performed through the installation structure between the transmission wheel, the groove plate, the retaining frame, and the shaft sleeve; the input end is opened, the output end is locked, and the torque of the transmission system is limited. The reverse transmission locking function and the overload protection function use the same elastic element, which reduces the required space of the mechanism, further improves the integration of the electric cylinder, and is more conducive to the installation and use of the electric cylinder in a compact space.

[0046] Example 2: Figure 6 As shown, an electric cylinder includes the reverse transmission locking and overload protection double-acting mechanism described in Example 1.

[0047] In some embodiments, the electric cylinder also includes a screw shaft 1, a motor 23, a transmission mechanism 15, a screw nut 20, and a piston rod 22; the power output end of the motor 23 is connected to the transmission wheel 11 through the transmission mechanism 15, and the screw shaft 1 spirally drives the screw nut 20, and the screw nut 20 is connected to the piston rod 22 for converting the rotational motion into the linear motion of the piston rod 22.

[0048] In some embodiments, the transmission mechanism 15 may be gear transmission or synchronous belt transmission. In this embodiment, the transmission mechanism is gear transmission.

[0049] Furthermore, in this embodiment, if Figure 6 As shown, the electric cylinder further includes a housing 17 , a second sleeve 18 , a bearing 19 , and a cylinder body 21 ; the cylinder body 21 is relatively fixedly connected to the housing 17 of the electric cylinder; and the screw shaft 1 is installed on the cylinder body 21 via the second sleeve 18 and the bearing 19 .

[0050] The reverse transmission locking and overload protection functions of the double-acting mechanism in this embodiment are respectively introduced below: Reverse transmission locking: The compression elastic member 2 is directly pressed on the second sleeve 18 fixedly connected to the screw shaft 1. The screw shaft 1 is installed on the cylinder body 21 via the second sleeve 18 and the bearing 19. No axial movement is generated during the movement, only rotational movement. Therefore, the screw shaft 1 and the second sleeve 18 will generate a reaction force in the right direction on the compression elastic member 2. The compression elastic member 2 presses the outer conical surface 3a of the tapered sleeve 3 against the inner conical surface 5a of the sleeve 5 to generate a friction torque. The sleeve 5 is fixedly connected to the housing 17 of the electric cylinder, and the screw shaft 1 is connected to the tapered sleeve 3 by a flat key 4. If the friction torque is sufficient, the screw shaft cannot rotate freely, thereby realizing the reverse transmission locking of the screw. When the motor 23 drives the convex sleeve 6 to rotate through the transmission mechanism 15 by the transmission wheel 11, the groove plate 10, the ball 8, the retaining frame 9, and the first sleeve 13, the convex structure 6a of the convex sleeve 6 will be lifted by the groove structure 3b of the cone sleeve 3, overcoming the pressure of the compression elastic member 2, so that a gap appears between the outer cone surface 3a of the cone sleeve 3 and the inner cone surface 5a of the sleeve 5, and the friction torque disappears, thereby realizing the opening of the input end and the locking of the output end.

[0051] Overload protection: The rotation of the output shaft of the motor 23 is transmitted to the transmission wheel 11 of the double-acting mechanism 16 through the transmission mechanism 15. The transmission wheel 11 and the first sleeve 13 can rotate freely, and the gasket 12 is arranged in the middle to prevent the transmission wheel 11 and the first sleeve 13 from direct wear. The groove plate 10 is installed on the transmission wheel 11, and the second mounting hole 10a of the groove plate 10 is connected with the circumferential limit mounting structure 11a of the transmission wheel 11, so that the groove plate 10 and the transmission wheel 11 are fixed in the circumferential direction, and torque can be transmitted. The groove 10b of the groove plate 10 is used to place the ball 8, and the ball 8 is placed in the first mounting hole 9a of the retainer 9. The second mounting structure 9b of the retainer 9 is connected with the first mounting structure 13a of the first sleeve 13 for torque transmission. The pressure plate 7 presses the ball 9 into the groove 10b of the groove plate 10. The third mounting structure 6c in the convex sleeve 6 for reverse transmission locking is connected with the first mounting structure 13a of the first sleeve 13 for torque transmission. A limit nut 14 is arranged on the right side of the first sleeve 13 to provide a reaction force to resist the pressure of the compression elastic member 2. Thus, the torque output by the motor 23 is transmitted to the convex sleeve 6 through the transmission mechanism 15, the transmission wheel 11, the groove plate 10, the ball 8, the retainer 9, and the first sleeve 13, and then transmitted to the screw shaft 1 through the taper sleeve 3 and the flat key 4, driving the screw nut 20 and the piston rod 22 fixed thereto to complete the linear motion of the electric cylinder. When the torque exceeds the set value (limit torque) due to load vibration, overload or mechanical failure, the compression elastic member 2 continues to be compressed, and the ball 8 rolls out of the groove 10b and slips, and detaches from the groove plate 10. At this time, the first sleeve 13 stops rotating. When the overload situation disappears, the connection is restored to prevent mechanical damage and achieve overload protection.

[0052] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A double-acting mechanism for reverse transmission locking and overload protection, characterized in that: include: First bushing; A transmission wheel, which is transmission-connected to the power output end of the motor, and is movably sleeved on the first shaft sleeve; The groove plate is relatively fixedly mounted on the transmission wheel in the circumferential direction and is provided with grooves for accommodating the balls; A retainer, which is connected and mounted on the first sleeve in a torque transmission manner, and is provided with a first mounting hole for accommodating a ball, and the inner diameter of the first mounting hole is larger than the diameter of the ball; A convex sleeve is installed on the first sleeve in a torque transmission connection, and a first end of the convex sleeve is directly or indirectly in contact with the ball, and a second end of the convex sleeve is provided with a convex structure; A cone sleeve is connected to the screw shaft through a key, the small end of the cone sleeve is provided with a groove structure matching with the protrusion structure, and the cone sleeve is provided with an outer cone surface; A sleeve is relatively fixedly connected to the housing of the electric cylinder and is located outside the cone sleeve. It is provided with an inner cone surface that matches the outer cone surface of the cone sleeve. The minimum inner hole diameter of the sleeve is smaller than the maximum outer diameter of the cone sleeve, and the maximum inner hole diameter of the sleeve is larger than the maximum outer diameter of the cone sleeve. A compression elastic member, one end of which is pressed on a limiting end face fixed relatively to the screw shaft, and the other end of which is abutted against the large end face of the tapered sleeve; and under the thrust of the compression elastic member, the tapered sleeve moves axially toward the convex sleeve, so that the outer conical surface of the tapered sleeve contacts the inner conical surface of the sleeve to generate a locking friction torque, and pushes the convex sleeve to press the ball into the groove of the groove plate for transmitting torque.

2. The reverse transmission locking and overload protection double-acting mechanism according to claim 1 is characterized in that: In the reverse transmission state, the transmission wheel does not provide torque, and the convex sleeve passively follows the tapered sleeve and cannot provide thrust to push the tapered sleeve out of the sleeve. Therefore, the locking friction torque provided by the sleeve always exists, and the outer cone surface of the tapered sleeve and the inner cone surface of the sleeve are always in a locked state, resulting in the inability to reversely transmit the torque and rotation of the screw shaft, thereby realizing reverse transmission mechanical locking.

3. The reverse transmission locking and overload protection dual-acting mechanism according to claim 1 is characterized in that: In the positive transmission state, the transmission wheel provides torque, which is transmitted to the convex sleeve through the groove plate, balls, retaining frame, and first sleeve in sequence. The convex structure of the convex sleeve is pressed into the groove structure of the tapered sleeve. The rotation of the convex sleeve squeezes the tapered sleeve through the convex structure, causing the tapered sleeve to separate from the sleeve. At this time, the locking friction torque provided by the sleeve disappears, and the torque can be transmitted to the screw shaft through the tapered sleeve and the key.

4. The reverse transmission locking and overload protection double-acting mechanism according to claim 3 is characterized in that: When the torque exceeds the set value, the compression elastic member continues to be compressed, the ball rolls out of the groove and slips, and separates from the groove plate. At this time, the first sleeve stops rotating, achieving overload protection.

5. The reverse transmission locking and overload protection dual-acting mechanism according to claim 1 is characterized in that: A circumferential limit mounting structure is provided at one end of the transmission wheel close to the groove plate, and a second mounting hole matching the circumferential limit mounting structure is provided at the center of the groove plate. The second mounting hole of the groove plate is connected to the circumferential limit mounting structure of the transmission wheel, so that the groove plate and the transmission wheel are fixed in the circumferential direction and can transmit torque.

6. The reverse transmission locking and overload protection dual-acting mechanism according to claim 1 is characterized in that: The first sleeve is provided with a first mounting structure; A second mounting structure matching the first mounting structure is provided at the center of the retainer, and the second mounting structure of the retainer is connected to the first mounting structure of the first sleeve for transmitting torque; A third mounting structure matching with the first mounting structure is provided at the center of the convex sleeve, and the third mounting structure of the convex sleeve is connected to the first mounting structure of the first shaft sleeve for transmitting torque.

7. The reverse transmission locking and overload protection dual-acting mechanism according to claim 1 is characterized in that: It also includes a pressure plate, which is arranged between the convex sleeve and the ball located in the retaining frame and is used to prevent the ball from wearing the convex sleeve.

8. The reverse transmission locking and overload protection dual-acting mechanism according to claim 1 is characterized in that: It also includes a gasket, which is arranged between the transmission wheel and the first shaft sleeve and is used to prevent the transmission wheel and the first shaft sleeve from direct wear.

9. The reverse transmission locking and overload protection dual-acting mechanism according to claim 1, characterized in that: A limiting member is also arranged at one end of the first sleeve away from the tapered sleeve, for providing a reaction force to resist the pressure of the compression elastic member.

10. The reverse transmission locking and overload protection double-acting mechanism according to claim 1, characterized in that: The compression elastic member is a compression spring.

11. The reverse transmission locking and overload protection dual-acting mechanism according to claim 1, characterized in that: The key connection adopts a flat key connection, a semicircular key connection, a wedge key connection or a tangential key connection.

12. The reverse transmission locking and overload protection double-acting mechanism according to claim 1, characterized in that: The protrusion structure is a V-shaped cone protrusion structure; and the groove structure is a V-shaped groove structure matched with the V-shaped cone protrusion structure.

13. The reverse transmission locking and overload protection dual-acting mechanism according to claim 1, characterized in that: The convex sleeve and the conical sleeve are coaxially arranged.

14. An electric cylinder, characterized in that: It comprises the reverse transmission locking and overload protection double-acting mechanism as described in any one of claims 1 to 13.

15. The electric cylinder according to claim 14, characterized in that: It also includes a motor, a transmission mechanism, a screw nut, and a piston rod; the power output end of the motor is connected to the transmission wheel through the transmission mechanism, the screw shaft spirally transmits the screw nut, and the screw nut is connected to the piston rod to convert the rotational motion into the linear motion of the piston rod.

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