A multi-stage telescopic arm without relative rotation

Abstract

The present invention discloses a multi-stage telescopic arm without relative rotation, comprising: a housing; a power assembly; a first telescopic assembly, including a first lead screw, a first slider, and a first telescopic arm; the first lead screw is located inside the housing and connected to the power assembly; the first telescopic arm is connected to the first slider and sleeved outside the first lead screw; a torque rod, capable of linearly moving relative to the first lead screw and not capable of rotating relative to the first lead screw; a second telescopic assembly, including a second lead screw, a second slider, and a second telescopic arm; the second lead screw is rotatably connected to the first telescopic arm and fixedly connected to the torque rod; the second slider is sleeved on the first telescopic arm and is keyed to the first telescopic arm; the second telescopic arm is connected to the second slider, and an internal thread matching with the second lead screw is arranged inside the second telescopic arm and the second telescopic arm is sleeved on the second lead screw. One technical effect of the present invention is that the present invention adopts a threaded structure transmission, which can realize multi-stage telescopic without relative rotation.

Description

Technical Field

[0001] The present invention belongs to the field of mechanical structures, and more specifically, relates to a multi-stage telescopic arm without relative rotation. Background Art

[0002] The common transmission forms of existing telescopic arms are hydraulic and rope (chain) transmissions. For example, a crane boom is mainly applied in occasions with large loads and unrestricted use spaces. When using a telescopic arm in a limited space, the aforementioned transmission forms are not suitable. When a screw transmission is used to achieve telescoping, a certain rotational deviation will occur due to the helix angle at the thread contact, making it difficult for the last-stage telescopic arm (near the load side) to achieve smooth linear motion without rotation during telescoping. As a result, the last-stage telescopic arm cannot be directly used as an actuator or directly connected to an actuator for applications where the load only requires translational motion (the load itself does not allow attitude or pitch changes but allows position changes).

[0003] Therefore, it is necessary to provide a multi-stage telescopic arm without relative rotation. Summary of the Invention

[0004] An object of the present invention is to provide a technical solution for a multi-stage telescopic arm without relative rotation.

[0005] According to one aspect of the present invention, there is provided a multi-stage telescopic arm without relative rotation, comprising:

[0006] A housing having a hollow cavity;

[0007] A power assembly disposed in the hollow cavity, at the rear end of the housing, capable of providing a rotational force;

[0008] A first telescopic assembly including a first lead screw, a first slider, and a first telescopic arm; the first lead screw is located in the housing and connected to the power assembly, and the power assembly can drive the first lead screw to rotate; the first slider is threadedly connected to the first lead screw and key-fitted with the housing, and when the first lead screw rotates, the first slider can linearly slide along the hollow cavity in the front or rear direction of the housing; the first telescopic arm is connected to the first slider and sleeved outside the first lead screw;

[0009] A torque rod, one end of the first lead screw has a hole and is sleeved on the torque rod, and the torque rod is configured to be able to linearly move relative to the first lead screw and not be able to rotate relative to the first lead screw;

[0010] The second telescopic assembly includes a second screw rod, a second slider, and a second telescopic arm; the second screw rod is rotationally connected to the first telescopic arm and fixedly connected to the torque rod; the second slider is sleeved on the first telescopic arm and cooperates with the first telescopic arm key; the second telescopic arm is connected to the second slider, and the second telescopic arm is provided with an internal thread that cooperates with the second screw rod and is sleeved on the second screw rod.

[0011] Optionally, the power assembly includes a motor and a coupling, and the motor is connected to the first screw rod through the coupling.

[0012] Optionally, the channel is a cylindrical channel, and the torque rod is a semi-cylindrical structure with the same diameter as the channel; a guide block is also provided in the first screw rod, and the guide block is fixed in the channel and against the torque rod, limiting the torque rod from moving in a straight line and not rotating relative to the first screw rod.

[0013] Optionally, the guide block is a semi-cylindrical structure having the same diameter as the channel.

[0014] Optionally, the guide block is fixedly connected in the channel by screws.

[0015] Optionally, the hole has a non-circular cross-section, and the cross-section of the torque rod matches the non-circular cross-section.

[0016] Optionally, the first telescopic arm is connected to the second screw rod via a self-locking pin structure, which includes a cylindrical pin, a spring, a pin ball, and an annular groove arranged on the inner wall of the first telescopic arm; the spring is arranged in the cylindrical pin, and the two pin balls are respectively arranged at both ends of the spring and both partially extend beyond the end of the cylindrical pin; the length of the cylindrical pin is smaller than the diameter of the annular groove, and the pin ball cooperates with the annular groove.

[0017] Optionally, the end of the torque rod facing away from the first screw rod has a through hole for the cylindrical pin to pass through, and is connected to the second screw rod by cooperating with the cylindrical pin.

[0018] Optionally, the second screw rod is rotatably connected to the first telescopic arm via a bearing structure.

[0019] A technical effect of the present invention is that the present invention adopts a threaded structure transmission, which can achieve multi-stage telescoping without relative rotation. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0021] Figure 1 is a schematic diagram of the overall structure of some embodiments of the present invention;

[0022] Figure 2 is a schematic diagram of a partial structure in some embodiments of the present invention;

[0023] Figure 3 is a schematic diagram of a partial structure of a torque rod in some embodiments of the present invention;

[0024] Figure 4 is a schematic diagram of the structure of a self-locking pin in some embodiments of the present invention.

[0025] In the figure: 1 housing, 11 hollow cavity, 2 power assembly, 21 motor, 22 coupling, 3 first telescopic assembly, 31 first lead screw, 32 first slider, 33 first telescopic arm, 34 hole, 4 torque rod, 41 guide block, 5 second telescopic assembly, 51 second lead screw, 52 second slider, 53 second telescopic arm, 61 cylindrical pin, 62 spring, 63 pin ball. Detailed implementation manners

[0026] The following will describe in detail the implementation manners of the present invention in conjunction with the drawings and embodiments, so as to fully understand how the present invention uses technical means to solve technical problems and achieve the realization process of technical effects and implement accordingly.

[0027] According to one aspect of the present invention, the present invention provides a multi-stage telescopic arm without relative rotation. In some embodiments, refer to Figures 1 to 4 , including a housing 1, a power assembly 2, a first telescopic assembly 3, a torque rod 4 and a second telescopic assembly 5.

[0028] The housing 1 is usually cylindrical, and can also be square columnar, multi-sided columnar, and the present invention does not limit this. The housing 1 has a hollow cavity 11. The hollow cavity 11 can be used to accommodate some or all of the other components. The front end of the housing 1 has an opening, which communicates the hollow cavity 11 with the outside of the housing, so that other components in the hollow cavity 11 can extend or retract.

[0029] The power assembly 2 is arranged in the hollow cavity 11 and is located at the rear end of the housing 1. The power assembly 2 is used to provide rotational power. Refer to Figure 1 , the power assembly 2 can include a motor 21 and a coupling 22, and the motor 21 is connected to the first telescopic assembly 3 through the coupling 22.

[0030] The first telescopic assembly 3 includes a first lead screw 31, a first slider 32 and a first telescopic arm 33. The first lead screw 31 is located in the hollow cavity 11 of the housing 1 and is connected to the power assembly 2. As Figure 1As shown, the first lead screw 31 can be connected to the coupling 22. The power assembly 2 can drive the first lead screw 31 to rotate. The first slider 32 is threadedly connected to the first lead screw 31 and is keyed to the housing 1. When the first lead screw 31 rotates, the first slider 32 can linearly slide along the hollow cavity 11 in the front-end direction or the rear-end direction of the housing 1. For example, when the first lead screw 31 rotates clockwise, the first slider 32 linearly moves along the hollow cavity 11 in the front-end direction of the housing 1, and when the first lead screw 31 rotates counterclockwise, the first slider 32 linearly moves along the hollow cavity 11 in the rear-end direction of the housing 1. Those skilled in the art can understand that the key fit refers to a fit method in which a mating keyway and a protrusion capable of sliding in the keyway are provided to limit it to linearly move only along the keyway, which is a conventional technical means in the art and will not be elaborated herein. The first telescopic arm 33 is connected to the first slider 32 and is sleeved outside the first lead screw 31. When the first slider 32 moves by the rotation of the first lead screw 31, the first telescopic arm 33 moves synchronously with the first slider 32 to extend or retract.

[0031] One end of the first lead screw 31 has a hole 34, and the first lead screw 31 is sleeved on the torque rod 4 through the hole 34. In some embodiments, referring to Figure 1 and Figure 3 , the hole 34 is a cylindrical hole 34, the torque rod 4 is a semi-cylindrical structure with the same diameter as the hole 34, and a guide block 41 is further provided in the first lead screw 31. The guide block 41 is fixed in the hole 34 and abuts against the torque rod 4 to limit the linear movement of the torque rod 4 and prevent it from rotating relative to the first lead screw 31. Further, the guide block 41 is a semi-cylindrical structure with the same diameter as the hole 34. Further, the guide block 41 is fixedly connected to the hole 34 by screws 42. It can enable the torque rod 4 to linearly move relative to the first lead screw 31 and not be able to rotate relative to the first lead screw 31. In some other embodiments, it can also be that the hole 34 has a non-circular cross-section, and the cross-section of the torque rod 4 fits the non-circular cross-section, such as a square channel, as long as it can achieve the purpose of restricting the rotation of the torque rod 4 relative to the first lead screw 31 and not restricting its linear movement relative to the first lead screw 31.

[0032] The second telescopic assembly 5 includes a second lead screw 51, a second slider 52, and a second telescopic arm 53. The second lead screw 51 is rotatably connected to the first telescopic arm 33 and fixedly connected to the torque rod 4, so that the first lead screw 31 can drive the second lead screw 51 to rotate, and the first telescopic arm 33 can drive the second lead screw 51 to linearly move relative to the first lead screw 31. In some embodiments, referring to Figure 1 and Figure 4 , the first telescopic arm 33 and the second lead screw 51 are connected by a self-locking pin structure. The self-locking pin structure includes a cylindrical pin 61, a spring 62, a pin ball 63, and a ring groove (not shown) provided on the inner wall of the first telescopic arm 33; the spring 62 is disposed inside the cylindrical pin 61, and the two pin balls 63 are respectively disposed at both ends of the spring 62 and both partially extend beyond the end of the cylindrical pin 61. The length of the cylindrical pin 61 is less than the diameter of the ring groove (not shown), and the pin ball 63 cooperates with the ring groove (not shown). The cylindrical pin 61 passes through the second lead screw 51, so that the second lead screw 51 is rotatably connected to the first telescopic arm 33 and can drive the second lead screw 51 to linearly move. Further, the cross-section of the ring groove is a semi-circle with the same diameter as the cut ball, achieving a better self-locking effect. Further, referring to Figure 4 , one end of the torque rod 4 facing away from the first lead screw 31 has a through hole for the cylindrical pin 61 to pass through, and is connected to the second lead screw 51 by cooperating with the cylindrical pin 61. In some other embodiments, the second lead screw 51 can also be rotatably connected to the first telescopic arm 33 through a bearing structure, as long as its rotational connection can be achieved and the first telescopic arm 33 can drive the second lead screw 51 to linearly move. In some other embodiments, the torque rod 4 can also be made by an integral molding process with the second lead screw 51, and the present invention does not limit this.

[0033] The second slider 52 is sleeved on the first telescopic arm 33 and is keyed to the first telescopic arm 33, so that the second slider 52 can only linearly move relative to the first telescopic arm 33. An internal thread that cooperates with the second lead screw 51 is provided inside the second telescopic arm 53, and the second telescopic arm 53 is sleeved on the second lead screw 51. The second telescopic arm 53 is connected to the second slider 52, so that when the second lead screw 51 rotates, the second telescopic arm 53 can only linearly move.

[0034] When the present invention is in use, the power component 2 drives the first lead screw 31 to rotate. The first lead screw 31 drives the first telescopic arm 33 to move linearly and drives the second lead screw 51 to rotate synchronously through the torque rod 4. The first telescopic arm 33 drives the second lead screw 51 to move linearly synchronously. The rotation of the second lead screw 51 also drives the second telescopic arm 53 to move linearly, thereby realizing a multi-stage telescopic arm without relative rotation. On the other hand, under the condition that other factors are the same, the present invention can achieve the required telescopic length faster than a single-stage lead screw, saving 1 / 2 of the time.

[0035] As used in the specification and claims, certain terms are used to refer to specific components or methods. Those skilled in the art should understand that different regions may use different terms to refer to the same component. The specification and claims do not use the difference in names as a way to distinguish components. As mentioned throughout the specification and claims, "comprising" is an open-ended term and should be interpreted as "including but not limited to". "Substantially" means within an acceptable error range. Those skilled in the art can solve the technical problem within a certain error range and basically achieve the technical effect. The subsequent description in the specification is the preferred embodiment for implementing the present invention, but the description is for the purpose of explaining the general principle of the present invention and is not used to limit the scope of the present invention. The protection scope of the present invention shall be subject to what is defined by the appended claims.

[0036] It should also be noted that the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a commodity or system including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such commodity or system. Without further limitation, an element defined by the statement "including one..." does not exclude the existence of another identical element in the commodity or system including the said element.

[0037] The above description shows and describes several preferred embodiments of the invention. However, as mentioned above, it should be understood that the invention is not limited to the form disclosed herein, should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be changed within the scope of the inventive concept described herein through the above teachings or the technology or knowledge in the relevant field. And the changes and modifications made by those skilled in the art without departing from the spirit and scope of the invention should all be within the protection scope of the appended claims of the invention.

Claims

1. A multi-stage telescopic arm without relative rotation, characterized in that, include: a housing having a hollow cavity; A power assembly is disposed in the hollow cavity and at the rear end of the shell, and is capable of providing rotational force; The first telescopic assembly comprises a first screw rod, a first slider, and a first telescopic arm; the first screw rod is located in the housing and connected to the power assembly, and the power assembly can drive the first screw rod to rotate; the first slider is threadedly connected to the first screw rod and cooperates with the housing key, and when the first screw rod rotates, the first slider can slide linearly along the hollow cavity toward the front end direction or the rear end direction of the housing; the first telescopic arm is connected to the first slider and is sleeved outside the first screw rod; A torque rod, wherein one end of the first screw rod has a hole and is sleeved on the torque rod, and the torque rod is configured to be able to move linearly relative to the first screw rod and cannot rotate relative to the first screw rod; The second telescopic assembly includes a second screw rod, a second slider, and a second telescopic arm; the second screw rod is rotationally connected to the first telescopic arm and fixedly connected to the torque rod; the second slider is sleeved on the first telescopic arm and cooperates with the first telescopic arm key; the second telescopic arm is connected to the second slider, and the second telescopic arm is provided with an internal thread that cooperates with the second screw rod and is sleeved on the second screw rod.

2. The multi-stage telescopic arm without relative rotation according to claim 1, characterized in that, The power assembly includes a motor and a coupling, and the motor is connected to the first screw rod through the coupling.

3. The multi-stage telescopic arm without relative rotation according to claim 1, characterized in that, The channel is a cylindrical channel, and the torque rod is a semi-cylindrical structure with the same diameter as the channel; a guide block is also arranged in the first screw rod, and the guide block is fixed in the channel and abuts against the torque rod, so as to limit the torque rod from moving in a straight line and not rotating relative to the first screw rod.

4. The multi-stage telescopic arm without relative rotation according to claim 3, wherein, The guide block is a semi-cylindrical structure having the same diameter as the hole.

5. The multi-stage telescopic arm without relative rotation according to claim 3, wherein The guide block is fixedly connected in the hole by screws.

6. The multi-stage telescopic arm without relative rotation according to claim 1, wherein The hole has a non-circular cross section, and the cross section of the torque rod matches the non-circular cross section.

7. The multi-stage telescopic arm without relative rotation according to claim 1, wherein The first telescopic arm and the second screw rod are connected by a self-locking pin structure, which includes a cylindrical pin, a spring, a pin ball and an annular groove arranged on the inner wall of the first telescopic arm; the spring is arranged in the cylindrical pin, and the two pin balls are respectively arranged at both ends of the spring and both partially extend beyond the end of the cylindrical pin, the length of the cylindrical pin is smaller than the diameter of the annular groove, and the pin ball cooperates with the annular groove.

8. The multi-stage telescopic arm without relative rotation according to claim 7, wherein, The end of the torque rod facing away from the first screw rod has a through hole for the cylindrical pin to pass through, and is connected to the second screw rod by cooperating with the cylindrical pin.

9. The multi-stage telescopic arm without relative rotation according to claim 1, wherein, The second screw rod is rotatably connected to the first telescopic arm via a bearing structure.

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