Shift shaft

Abstract

The invention discloses a shift shaft, comprising a mounting shell, a sliding assembly and a plurality of gear assemblies arranged in a cavity of the mounting shell, wherein a driving motor is embedded in a sliding gear constituting the sliding assembly, a driving wheel is fixed on an output shaft of the driving motor, a guide rail is arranged on the sliding shaft to limit a sliding track of the driving wheel, the number of components is small, the overall structure is simple and compact, the driving motor is embedded and does not occupy additional space, and the volume of the assembled shift shaft is effectively reduced, after the driving motor is started, the sliding gear automatically slides on the sliding shaft under the drive of the driving wheel, and meshes with the inner gear rings of different gear assemblies, thereby realizing the switching of gears and achieving the purpose of speed change, and the shifting process does not require external force, and the operation is more convenient.

Description

Technical Field

[0001] The invention relates to the field of gear shift control equipment, in particular to a gear shift rotating shaft. Background Art

[0002] The existing shift shaft is mostly a double-row sliding gear transmission mechanism, including dozens of parts such as sliding fork, spline shaft, positioning steel ball group, pin, shaft, guide key, etc. The structure and assembly procedures are complicated and not suitable for installation on small mechanical equipment. At the same time, too many parts increase the weight of the shift shaft, which will be cumbersome to use on small mechanical equipment.

[0003] In addition, there is no anti-reverse device in the common sliding gear transmission mechanism. The gear can rotate clockwise or counterclockwise. If the gear reverses during use, the machine will not be able to operate normally, which poses a certain risk of use. Based on this, an anti-reverse device is generally set in its control device, but this will make the linkage between the control mechanism and the shift shaft more complicated. Similarly, the existing shift shaft parts are complex and bulky, and cannot meet the needs of smaller mechanical equipment such as power-assist mechanisms. Summary of the invention

[0004] The purpose of the present invention is to solve at least one of the technical problems existing in the prior art and to provide a shift shaft with a simple and compact structure and capable of achieving miniaturization.

[0005] According to an embodiment of the present invention, the shift shaft includes a mounting shell, the interior of which forms a cavity; a sliding assembly is arranged in the cavity, and has a sliding shaft connected to the mounting shell and a sliding gear sleeved on the sliding shaft, a driving motor is embedded in the interior of the sliding gear, a driving wheel is fixed on the output shaft of the driving motor, a guide rail for limiting the sliding trajectory of the driving wheel is provided on the sliding shaft, and the guide rail extends along the axial direction of the sliding shaft; a plurality of gear assemblies are all arranged in the cavity and are respectively sleeved outside the sliding shaft, and each of the gear assemblies has an inner gear ring meshing with the sliding gear.

[0006] The shift shaft according to the embodiment of the present invention has at least the following beneficial effects: the shift shaft comprises a mounting shell, a sliding assembly and a plurality of gear assemblies arranged in a cavity of the mounting shell, a driving motor is embedded in the sliding gear constituting the sliding assembly, a driving wheel is fixed on the output shaft of the driving motor, a guide rail is arranged on the sliding shaft to limit the sliding trajectory of the driving wheel, the number of components is small, the overall structure is simple and compact, and the driving motor is embedded and does not occupy additional space, which effectively reduces the volume of the assembled shift shaft, after starting the driving motor, the sliding gear is driven by the driving wheel, and automatically slides on the sliding shaft to achieve meshing with the inner gear rings of different gear assemblies, thereby achieving gear switching and achieving the purpose of speed change, and the shifting process does not require external force, and the operation is more convenient.

[0007] According to some embodiments of the present invention, the spacing between adjacent gear assemblies is smaller than the tooth width of the sliding gear, and each of the gear assemblies is a forward rotation mechanism, a reverse rotation mechanism and a deceleration mechanism.

[0008] According to some embodiments of the present invention, the forward rotation mechanism, reverse rotation mechanism and deceleration mechanism are arranged in sequence along the axial direction of the sliding shaft, the deceleration mechanism is flush with one end of the guide rail, and the distance from the forward rotation mechanism to the other end of the guide rail is not less than the tooth width of the sliding gear.

[0009] According to some embodiments of the present invention, the forward rotation mechanism and the reverse rotation mechanism are both ratchet mechanisms, respectively comprising a ratchet and a braking rod with one end inserted into the tooth groove of the ratchet, each of the ratchet wheels is respectively provided with an inner gear ring meshing with the sliding gear, and the ends of the two braking rods connected to the ratchet wheels respectively form an inclined surface, and the inclination directions of the two inclined surfaces are opposite.

[0010] According to some embodiments of the present invention, each of the braking rods is respectively connected to at least one elastic element.

[0011] According to some embodiments of the present invention, an elastic element is sleeved on the outer circumference of each of the braking rods, and the elastic element is a spring.

[0012] According to some embodiments of the present invention, the deceleration mechanism includes a friction wheel and a friction ring sleeved on the outside of the friction wheel, and the friction ring is fixedly connected to the mounting shell.

[0013] According to some embodiments of the present invention, the friction ring is made of rubber.

[0014] According to some embodiments of the present invention, the driving wheel is a gear, and the guide rail is a rack meshing with the driving wheel.

[0015] According to some embodiments of the present invention, the driving motor is a micro stepping motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention will be further described below in conjunction with the accompanying drawings:

[0017] Figure 1 is an overall structural diagram of a shift shaft according to an embodiment of the present invention;

[0018] Figure 2 is an assembly diagram of a sliding assembly and a shift assembly of a shift shaft according to an embodiment of the present invention;

[0019] Figure 3 is an exploded view of a sliding assembly and a shift assembly of a shift shaft according to an embodiment of the present invention;

[0020] Figure 4 is an assembly diagram of a sliding assembly according to an embodiment of the present invention;

[0021] Figure 5 is a gear position distribution diagram of a gear shift shaft according to an embodiment of the present invention;

[0022] Figure 6 2 is a structural diagram of a pawl according to an embodiment of the present invention. DETAILED DESCRIPTION

[0023] This section will describe in detail the specific embodiments of the present invention. The preferred embodiments of the present invention are shown in the accompanying drawings. The purpose of the accompanying drawings is to supplement the description of the text part of the specification with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of the present invention, but it cannot be understood as a limitation on the scope of protection of the present invention.

[0024] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., and orientations or positional relationships indicated are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0025] In the description of the present invention, "several" means one or more, "more" means more than two, "greater than", "less than", "exceed" etc. are understood as not including the number itself, and "above", "below", "within" etc. are understood as including the number itself. If there is a description of "first" or "second", it is only used for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0026] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0027] Reference Figures 1 to 5 The shift shaft of the embodiment of the present invention includes a mounting shell 1, a sliding assembly 2 and a plurality of gear assemblies.

[0028] Specifically, a cavity is formed inside the mounting shell 1; the sliding assembly 2 is arranged in the cavity, and comprises a sliding shaft 21 connected to the mounting shell 1 and a sliding gear 22 sleeved on the sliding shaft 21, a driving motor 23 is embedded in the sliding gear 22, a driving wheel is fixed on the output shaft of the driving motor 23, a guide rail 211 for limiting the sliding trajectory of the driving wheel is arranged on the sliding shaft 21, and the guide rail 211 extends along the axial direction of the sliding shaft 21; each gear assembly is arranged in the cavity and is respectively sleeved outside the sliding shaft 21, and each gear assembly has an inner gear ring meshing with the sliding gear 22.

[0029] The shift shaft according to the embodiment of the present invention comprises a mounting shell 1, a sliding assembly 2 and a plurality of gear assemblies arranged in a cavity of the mounting shell 1, a driving motor 23 is embedded in a sliding gear 22 constituting the sliding assembly 2, a driving wheel is fixed on the output shaft of the driving motor 23, a guide rail 211 is arranged on the sliding shaft 21 to limit the sliding track of the driving wheel, the number of components is small, the overall structure is simple and compact, and the driving motor 23 is embedded and does not occupy additional space, thereby effectively reducing the volume of the assembled shift shaft, after starting the driving motor 23, driven by the driving wheel, the sliding gear 22 automatically slides on the sliding shaft 21, realizes the position change, and meshes with the inner gear rings of different gear assemblies, thereby realizing the switching of gears and achieving the purpose of speed change, and the shifting process does not require external force, and the operation is more convenient.

[0030] In some embodiments of the present invention, each gear assembly is a forward mechanism 31, a reverse mechanism 32 and a retarding mechanism 33, respectively, forming three gears of a forward steering gear, a reverse steering gear and a retarding gear; it should be noted that, in this embodiment, the forward direction is clockwise rotation, and the reverse direction is counterclockwise rotation. Furthermore, the forward mechanism 31, the reverse mechanism 32 and the retarding mechanism 33 are arranged in sequence along the axial direction of the sliding shaft 21, and it is necessary to ensure that the spacing between the reverse mechanism 32 and the forward mechanism 31 and the retarding mechanism 33 is smaller than the tooth width of the sliding gear 22, so as to avoid an unexpected neutral gear when the gear is switched, which may cause a jam in the gear shifting process and affect the user experience. Furthermore, the deceleration mechanism 33 of the present embodiment is flush with one end of the guide rail 211, and the distance from the forward rotation mechanism 31 to the other end of the guide rail 211 is not less than the tooth width of the sliding gear 22. When the sliding gear 22 moves to the end of the guide rail 211 on the side where the forward rotation mechanism 31 is located, the sliding gear 22 can rotate freely without being restricted by other mechanisms. At this time, the gear position of the shift shaft will be in a neutral state.

[0031] Specifically, the forward rotation mechanism 31 and the reverse rotation mechanism 32 of this embodiment are both ratchet mechanisms, each comprising a ratchet 34 and a pawl 35 with one end inserted into the tooth groove of the ratchet 34, and an inner gear ring meshing with the sliding gear 22 is provided at the middle through hole of each ratchet 34. Figure 6 As shown, in order to prevent the ratchet wheels 34 from reversing and achieve reverse braking of the ratchet wheels 34, the ends of the brake rods 35 connected to the ratchet wheels 34 form an inclined surface 351 respectively; and since the rotation directions of the ratchet wheels 34 of the forward rotation mechanism 31 and the reverse rotation mechanism 32 are opposite, the inclined directions of the inclined surfaces 351 of the two brake rods 35 are opposite after assembly. Taking the forward rotation mechanism 31 as an example, when the ratchet wheel 34 rotates clockwise, the outer teeth of the ratchet wheel 34 rotate along the inclined surface 351 and push the brake rod 35 upward until it enters the tooth groove again, and the brake rod 35 performs linear reciprocating motion at this time; and when the ratchet wheel 34 rotates counterclockwise, the side surface of the brake rod 35 on the opposite side of the inclined surface 351 will directly fit with the teeth of the ratchet wheel 34, thereby preventing the gear from rotating counterclockwise. In order to improve the braking effect, a platform 352 can be cut along the axial direction of the braking rod 35 at one end where the braking rod 35 and the ratchet 34 are connected, and the surface of the platform 352 is opposite to the inclined surface 351. In this way, when the ratchet 34 performs a reverse motion, its teeth will fit with the surface of the platform 352, the contact area between the two will be larger, and the anti-reversal effect will be better.

[0032] In order to make the reciprocating motion of each pawl 35 smoother and improve the reset speed of the pawl 35, each pawl 35 is connected to at least one elastic element 353, and each elastic element 353 is arranged around the outer circumference of the pawl 35, or connected to the end of the pawl 35 away from the ratchet 34. Figure 6 In this embodiment, an elastic element 353 is sleeved on the outer circumference of each pawl 35, and the elastic element 353 is a spring. When the ratchet 34 constituting the reversing mechanism 32 rotates counterclockwise, the outer teeth of the ratchet 34 rotate along the inclined surface 351 of the pawl 35 and push the pawl 35 away. At this time, the spring is compressed until the pawl 35 reaches the next tooth groove of the ratchet 34. At this time, the external force acting on the pawl 35 is reduced, and the spring recovers its deformation and drives the end of the pawl 35 into the tooth groove.

[0033] In an embodiment of the present invention, the deceleration mechanism 33 includes a friction wheel 331 and a friction ring 332 sleeved on the outer side of the friction wheel. The friction ring 332 is fixedly connected to the mounting shell 1, so as to ensure that the position of the friction ring 332 is fixed during the rotation of the friction wheel, so as to avoid the reduction of the deceleration buffering effect due to the friction ring 332 rotating with the friction wheel. After the sliding gear 22 enters the friction wheel and meshes with it to generate rotation, the friction wheel and the friction ring 332 generate friction resistance due to relative movement, thereby achieving the effect of slowing down. Specifically, the friction ring 332 is made of rubber. In order to further increase the friction between the friction wheel and the friction ring 332, in some embodiments, a plurality of protrusions are provided on the inner surface of the friction ring 332. More preferably, each protrusion is integrally formed with the friction ring 332 to improve the connection firmness of the protrusion on the friction ring 332.

[0034] In some embodiments of the present invention, the drive motor 23 adopts a micro stepping motor. At the same time, the driving wheel fixed on the output shaft of the drive motor 23 is a gear, and the guide rail 211 is a rack meshing with the driving wheel, and the rack extends from one end of the sliding shaft 21 to the other end.

[0035] The shift shaft of the embodiment of the present invention has an overall shape of a nested cylinder after assembly, and has four gears: neutral, forward, reverse and slow. By starting the drive motor 23 and driving the sliding gear 22 to slide on the guide rail 211, the adjustment and transformation of different gears can be realized to achieve the purpose of speed change without the need for additional driving force by the user, and the operation is more convenient.

[0036] The shift shaft of the embodiment of the present invention can be used in an elbow joint assist device. Specifically, the elbow joint assist device also includes a forearm protector and an upper arm protector, and the mounting shell of the shift shaft includes an upper arm shaft housing 11 and an lower arm shaft housing 12 respectively connected to the upper arm protector and the lower arm protector.

[0037] The elbow joint assist device, by configuring the shift shaft of the embodiment of the present invention, enables the user to use his or her arm to exert force during the shifting process without the need for the user to do so, making it more convenient for patients and the elderly to use. When the shift shaft is in the forward gear or reverse gear, it can assist the user's arm to slowly raise or lower the arm and complete operations such as grabbing objects; when the shift shaft is in the slow gear, it can help slow down the movement speed of the user's arm and provide support for the arm when it is retracted, so as to complete the slow lowering of the arm; when the shift shaft is in the neutral gear, the elbow joint assist device only serves as a protection, and the user's arm can move freely without being interfered by external forces.

[0038] Of course, the design and creation of the present invention is not limited to the above-mentioned implementation modes. Those skilled in the art may make equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. A gear shift shaft, characterized in that: include: Install the shell to form a cavity inside; A sliding assembly is arranged in the cavity, and comprises a sliding shaft connected to the mounting shell and a sliding gear sleeved on the sliding shaft, a driving motor is embedded in the sliding gear, a driving wheel is fixed on the output shaft of the driving motor, a guide rail for limiting the sliding track of the driving wheel is arranged on the sliding shaft, and the guide rail extends along the axial direction of the sliding shaft; A plurality of gear assemblies are arranged in the cavity, each of the gear assemblies is sleeved outside the sliding shaft, and each of the gear assemblies has an inner gear ring meshing with the sliding gear; Wherein, the spacing between adjacent gear assemblies is smaller than the tooth width of the sliding gear, and each of the gear assemblies is a forward rotation mechanism, a reverse rotation mechanism and a deceleration mechanism; The driving wheel is a gear, and the guide rail is a rack meshed with the driving wheel.

2. The shift shaft according to claim 1, characterized in that: The forward rotation mechanism, reverse rotation mechanism and deceleration mechanism are arranged in sequence along the axial direction of the sliding shaft, the deceleration mechanism is flush with one end of the guide rail, and the distance from the forward rotation mechanism to the other end of the guide rail is not less than the tooth width of the sliding gear.

3. The shift shaft according to claim 1, characterized in that: The forward rotation mechanism and the reverse rotation mechanism are both ratchet mechanisms, respectively including a ratchet and a braking rod with one end inserted into the tooth groove of the ratchet. Each ratchet is provided with an internal gear ring meshing with the sliding gear. The ends of the two braking rods connected to the ratchet form an inclined surface respectively, and the inclination directions of the two inclined surfaces are opposite.

4. The shift shaft according to claim 3, characterized in that: Each of the braking rods is connected to at least one elastic element.

5. The shift shaft according to claim 4, characterized in that: An elastic element is sleeved on the outer circumference of each of the braking rods, and the elastic element is a spring.

6. The shift shaft according to claim 1, characterized in that: The deceleration mechanism comprises a friction wheel and a friction ring sleeved on the outer side of the friction wheel, and the friction ring is fixedly connected to the mounting shell.

7. The shift shaft according to claim 6, characterized in that: The friction ring is made of rubber.

8. The shift shaft according to claim 1, characterized in that: The driving motor is a micro stepping motor.

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