Pneumatic pre-screwing wrench

Abstract

The utility model discloses a pneumatic pre-screwing wrench, and aims to solve the technical problem that an existing wrench cannot realize efficient bolt disassembly in a limited space environment. The spanner head is arranged at the corresponding end of the spanner body, the inner edge contour of the spanner head is larger than the excircle contour of a bolt to be screwed, and the air channels are correspondingly linearly arrayed in the spanner head and used for outputting air flow pushing the bolt to be screwed to rotate. The plurality of air valves are arranged in the wrench body in one-to-one correspondence with the air passages, are used for communicating with the air passages and correspondingly switch a positive pressure air source or a negative pressure air source, and the microcontroller is arranged in the wrench body and is used for controlling the air valves to be correspondingly conducted at corresponding moments; the radian of an end fitting curve of each air channel in the wrench head is matched with the radian of an externally tangent arc of a bolt to be screwed. According to the pneumatic pre-screwing wrench, rapid pre-screwing of a bolt can be achieved without a run movement space, and the pneumatic pre-screwing wrench can adapt to narrow and limited working environments.

Description

Technical Field

[0001] This application relates to the field of mechanical tools, and particularly to a pneumatic pre-rotation wrench. Background Art

[0002] A pneumatic wrench is an efficient, environmentally friendly and energy-saving fastening tool, which has wide applications in the field of industrial machinery. The pneumatic wrench mainly uses compressed air as the power source, and utilizes a high-speed rotating pneumatic motor to drive a torque multiplier to achieve large torque output.

[0003] However, under different working conditions, there are huge differences in the installation positions of bolts. For an installation environment with a compact installation and limited space, due to the interference and limitation of the rotation space of the working stroke of an electric or pneumatic wrench by other components of the equipment, and the electric or pneumatic wrench requires an operating space adapted to the wrench body when in use, it is difficult for the existing large-stroke wrenches to disassemble and assemble bolts in a limited space environment; in some special occasions, even a ratchet wrench with a very small stroke is not applicable; when using a traditional manual wrench to disassemble bolts, due to the narrow and limited operating space, only a little rotation can be carried out bit by bit, resulting in low bolt disassembly efficiency, high labor intensity, and even affecting the construction period.

[0004] The information disclosed in this background art section is only used to deepen the understanding of the background art of the present disclosure, and should not be regarded as an admission or any form of implication that this information constitutes the prior art known to those skilled in the art. Summary of the Invention

[0005] In view of at least one of the above technical problems, the present disclosure provides a pneumatic pre-rotation wrench, aiming to solve the technical problem that the existing wrenches cannot achieve efficient bolt disassembly in a limited space environment.

[0006] According to one aspect of the present disclosure, there is provided a pneumatic pre-rotation wrench, which includes a wrench body, a wrench head provided at the corresponding end of the wrench body and having an inner edge contour larger than the circumscribed circle contour of the bolt to be rotated, a plurality of air channels linearly arrayed in the wrench head for outputting air flow to push the bolt to be rotated, a plurality of air valves provided in the wrench body corresponding to each of the air channels for communicating each of the air channels and correspondingly switching between a positive pressure air source and a negative pressure air source, and a microcontroller provided in the wrench body for controlling the air valves to be correspondingly conducted at corresponding moments; the fitting curve radian of the end of each of the air channels in the wrench head matches the circumscribed arc radian of the bolt to be rotated.

[0007] In some embodiments of the present disclosure, the wrench head includes two arm plates fixedly provided with the wrench body and oppositely arranged, and the distance between the two arm plates is larger than the circumscribed circle diameter of the bolt to be rotated.

[0008] In some embodiments of the present disclosure, each of the air passages is linearly arrayed between the two arm plates along a perpendicular line perpendicular to the two arm plates.

[0009] In some embodiments of the present disclosure, the airflow output by at least two of the air passages acts on a single prism surface corresponding to the bolt to be screwed.

[0010] In some embodiments of the present disclosure, the airflow outlet of the air passage is a rectangle with a side length not less than the height of the bolt to be screwed.

[0011] In some embodiments of the present disclosure, the air valve is a high-speed air valve.

[0012] In some embodiments of the present disclosure, a positive pressure air source interface and a negative pressure air source interface corresponding to and communicating with a positive pressure air source and a negative pressure air source are provided on the wrench body, and each of the air valves is respectively communicated with the positive pressure air source interface and the negative pressure air source interface.

[0013] In some embodiments of the present disclosure, a key and a display screen for inputting control information and displaying control parameters are embedded in the wrench body and are correspondingly communicatively connected to the microcontroller.

[0014] One or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages:

[0015] By controlling the high-speed air valves corresponding to each air passage through the microcontroller, a positive pressure airflow or a negative pressure airflow is formed to act on the surface of the bolt to be screwed without moving the wrench body, so as to promote the rotation of the bolt to achieve the purpose of pre-tightening the bolt. Therefore, the automatic pre-screwing of the bolt can be realized without a stroke movement space, so as to adapt to the rapid pre-screwing operation of the bolt in a narrow and limited space. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic structural diagram of a pneumatic pre-screwing wrench in an embodiment of the present application.

[0017] Figure 2 It is a partial process schematic diagram of a bolt being rotated by a pneumatic pre-screwing wrench in an embodiment of the present application.

[0018] In the above figures, 1 is the wrench body, 2 is the wrench head, 21 is the arm plate, 3 is the air passage, 41 is the positive pressure air source interface, 42 is the negative pressure air source interface, 51 is the display screen, 52 is the key, and 6 is the bolt to be screwed. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0019] In the description of the present application, it should be understood that the orientation or positional relationships indicated by the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", "vertical", "horizontal", "clockwise", "counterclockwise", etc. are based on the orientation or positional relationships shown in the drawings. These are only for the convenience of describing the present application 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 thus should not be construed as a limitation on the present application. For the "connection" and "coupling" involved in the present application, unless otherwise specified, both direct and indirect connections (couplings) are included.

[0020] To better understand the technical solution of the present application, the above technical solution will be described in detail below in conjunction with the drawings of the specification and specific embodiments.

[0021] To solve the problems that existing wrenches are difficult to adapt to restricted working spaces and require a certain working stroke during operation, this example discloses a pneumatic pre-rotating wrench. See Figure 1 , which includes a wrench body 1 and a wrench head 2 provided at one end of the wrench body 1.

[0022] The wrench body 1 is the main body of the wrench, which plays the role of facilitating personnel to hold, enhancing the structural strength of the wrench, and protecting the internal structural components. A wrench head 2 is provided on the end side of the wrench body 1. The inner edge contour of the wrench head 2 is larger than the circumscribed circle contour of the bolt to be rotated. In this way, during use, the bolt to be rotated is located inside the wrench head 2. On the one hand, it is convenient for the operator to accurately align the wrench with the bolt to be rotated when the vision is not clear, and the wrench head 2 plays a guiding and limiting role; on the other hand, it is convenient to limit the air flow path during work, so that the air flow is concentrated within the range of the wrench head, thereby avoiding the problem that the air flow is blocked by the bolt edge surface and the flow path diverges. Specifically, in this embodiment, the wrench head 2 includes two oppositely arranged arm plates 21, and the spacing width between the two arm plates 21 is larger than the circumscribed circle diameter of the bolt to be rotated, so as to avoid the position interference of the arm plates 21 on the rotation of the bolt.

[0023] To achieve the force-driven rotation of the bolt located between the two arm plates 21 of the wrench head 2, see Figure 1, between the two arm plates 21 of the wrench head 2, a number of air channels 3 are linearly arrayed along a perpendicular line perpendicular to the two arm plates 21, and high-speed airflows with relatively large pressures are output through the air channels. By directly contacting the prism surface of the bolt to be screwed with the high-speed airflows, the rotation of the bolt is promoted. In this embodiment, each air channel 3 is a hollow prism structure with a rectangular end air output port. The air channels 3 are independent of each other and are correspondingly clamped and fixed in the wrench body 1, which facilitates subsequent maintenance and replacement of the air channels. In addition, in this example, the length of the rectangular side of the air output port of the air channel 2 parallel to the edge angle of the bolt to be screwed is not less than the edge angle height of the bolt to be screwed, that is, the height of the bolt, so as to ensure that there is sufficient airflow in contact with the bolt prism surface, and there is a large enough contact force area between the two, improving the force reliability of the bolt. In addition, in this embodiment, in order to further ensure that the airflow output by the air channel 3 can effectively push the bolt to be screwed, the number of air channels 3 is set to satisfy that at least the airflow output by the air channels acts on the corresponding prism surface of the bolt to be screwed, thereby improving the force intensity of a single prism surface of the bolt and further improving the force reliability of the bolt.

[0024] Considering that the prism surfaces of the bolt are located on different planes, and the airflow intensity will continuously decrease with its flow path. To ensure that the airflow output by the air channel can act on the corresponding prism surface of the bolt to be screwed to the greatest extent, in this embodiment, see Figure 1 , the radian of the fitting curve of the end of each air channel for outputting airflow is matched with the circumscribed arc radian of the bolt to be screwed, that is, the fitting curve of the air channel end is a circular arc concentric with the circumscribed circle of the bolt. Thus, the distance from the air output port of each air channel to the circumscribed circle of the bolt to be screwed is the same, avoiding the problem that when the end faces of the air channels are coplanar, there is a large loss when the airflows output from the two side air channels reach the corresponding prism surface of the bolt to be screwed, resulting in a significant reduction in the driving force on the bolt.

[0025] Since there are differences in the forces on different prism surfaces of the bolt during the screwing process, in this embodiment, each air channel is respectively connected to a positive pressure air source and a negative pressure air source. The positive pressure air source ejects positive pressure airflow through the corresponding air channel to act on the corresponding bolt prism surface, thereby promoting the rotation of the bolt; the negative pressure air source sucks to form negative pressure airflow through the corresponding air channel to act on the corresponding bolt prism surface, thereby attracting the rotation of the bolt.

[0026] Specifically, in this example, in order to achieve the purpose of the air channels outputting different airflows at different times to rotate the bolt, each air channel 3 is connected with an air valve one by one. In this example, the air valve adopts a high-speed air valve. The high-pressure air valve can withstand the required air pressure requirements, ensuring that it can work normally in a high-pressure environment. Moreover, the high-speed air valve has a high air channel on-off frequency and a large number of frequencies, and can be quickly opened and closed to meet the requirements of rapid on-off; furthermore, each air channel is respectively connected to the positive pressure air source and the negative pressure air source through the corresponding high-speed air valve, and the on-demand switching of the air source connected to the air channel at a certain moment is realized through the high-speed air valve. Among them, seeFigure 1 At the bottom of the wrench body 1, there are a positive pressure air source interface 41 and a negative pressure air source interface 42, which are respectively used to connect to the positive pressure air source and the negative pressure air source; inside the wrench body, each high-speed air valve is respectively connected to the positive pressure air source interface 41 and the negative pressure air source interface 42 through corresponding positive pressure branches and negative pressure branches to obtain the positive pressure and negative pressure air flow sources required for the operation of each air passage.

[0027] In order to achieve on-demand control of the working timing and output air flow of each air passage, in this embodiment, a microcontroller for controlling each high-speed air valve is provided inside the wrench body 1 to control the on / off of each high-speed air valve and the switching of the positive and negative pressure air sources. In addition, a key 51 and a display screen 51 that are communicatively connected to the microcontroller are also embedded in the wrench body 1. The number of bolt edges, rotation speed, opening and closing control parameters are input through the keys, and the control parameters currently obtained by the wrench are displayed through the display screen.

[0028] Specifically, referring to Figure 2 , taking the screwing of a hexagonal bolt as an example in this example, a total of 8 air passages 3 are provided in this example, and each air passage is respectively connected to the positive pressure air source and the negative pressure air source through the corresponding high-speed air valve. At the initial moment, all the high-speed air valves are closed. After the pneumatic wrench is started, the number of edges of the bolt to be rotated, the contour information of the circumscribed circle diameter of the bolt, and the required rotation direction, i.e., loosening or tightening, are input to the microcontroller through the keys. Thus, the microcontroller calculates the vertical distance from each bolt facet to each air passage according to the bolt contour information. In this embodiment, with the bolt facets symmetrically located in the middle of the wrench head as the initial state, before use, the operator adjusts the position of the bolt so that one facet faces the operator, and then the wrench head of this pneumatic pre-screwing wrench is correspondingly surrounded outside the bolt to be screwed. After the pneumatic wrench is started, the high-speed air valves corresponding to each air passage respectively respond to the control sequence of the microcontroller and output air flow as needed. After the pneumatic wrench is started, for the convenience of description, Figure 2 the air passages of the wrench in Figure 2 are respectively named the first to the eighth air passages from left to right. After starting, referring to Figure 2 Fig. (a), the first and second air passages are connected to the negative pressure air source, and the seventh and eighth air passages are connected to the positive pressure air source. Since the air passages facing the bolt facets cannot form a rotational torque, the third, fourth, fifth, and sixth air passages are controlled to be closed. Thus, a negative pressure is formed on the left side of the bolt central axis, and a positive pressure air flow impact is formed on the right side of the bolt central axis, and the bolt rotates under the force; after the bolt rotates 15°, since the force-bearing surface of the bolt changes, referring to Figure 2(c) The force on the bolt gradually decreases. At this time, the first, second, third, and fourth airways are connected to the negative pressure air source, and the fifth, sixth, seventh, and eighth airways are connected to the positive pressure air source. The bolt force continues to move about 15° to Figure 2 (d) After the state shown, the first, second, third and fourth airways are connected to the negative pressure air source, the fifth and sixth airways are closed, and the seventh and eighth airways are connected to the positive pressure air source. The bolt is impacted by the airflow and continues to rotate until Figure 2 (e) shows the state, at this time, the bolt rotates a total of 60°, and the outer edge profile of the bolt in this state is consistent with the profile of the initial state. Therefore, the microcontroller uses the airway control sequence corresponding to the 60-degree rotation of the hexagonal bolt as the basic control sequence, and repeatedly outputs the control sequence to achieve continuous rotation of the bolt. In some other embodiments, for other angular numbers N of the bolt, the microcontroller uses the rotation of the bolt at an angle of M degrees as the basic control sequence, where M=360° / N. In addition, in this embodiment, the screwing speed of the wrench can be controlled by a button. After the microcontroller obtains the speed control parameter, the sequence timing of the basic control sequence and the output frequency of the basic control sequence are increased or decreased in a corresponding proportion, thereby achieving the adjustment of the wrench speed. In some occasions where the bolt tightness is required to be high, after the pneumatic wrench can no longer drive the bolt to rotate, a manual wrench is used for the final tightening operation. Since most of the screwing operations are completed by the pneumatic wrench, the manual wrench only needs a small stroke to complete the bolt tightening, and the overall operation efficiency is significantly improved compared to the manual wrench alone.

[0029] In addition, in the present embodiment, the outer cover of the wrench body is provided with a detachable soft rubber cover, and the soft rubber cover can be replaced according to different needs. If there are requirements for gripping force and anti-slip performance, the soft rubber cover with a harder texture and deeper patterns can be replaced accordingly. If there is a need for shock absorption, the soft rubber cover with a softer texture and better shock absorption performance can be replaced accordingly to reduce the discomfort caused by vibration or impact during use.

[0030] Although some preferred embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present application.

[0031] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the inventive concept. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A pneumatic pre-rotating wrench, characterized in that, It includes a wrench body, a wrench head provided at the corresponding end of the wrench body and having an inner edge contour larger than the circumscribed circle contour of the bolt to be screwed, a number of air channels correspondingly arranged linearly in the wrench head for outputting airflows to push the bolt to be screwed to rotate, a number of air valves provided in the wrench body corresponding to each of the air channels for communicating each of the air channels and correspondingly switching a positive pressure air source or a negative pressure air source, and a microcontroller provided in the wrench body for controlling the air valves to be correspondingly conducted at corresponding moments; the fitting curve radian of the end of each of the air channels in the wrench head matches the circumscribed circle radian of the bolt to be screwed.

2. The pneumatic pre-rotation wrench according to claim 1, characterized in that, The wrench head includes two arm plates fixedly provided with and oppositely arranged to the wrench body, and the distance between the two arm plates is larger than the circumscribed circle diameter of the bolt to be screwed.

3. The pneumatic pre-rotation wrench according to claim 2, characterized in that, Each of the air channels is correspondingly arranged linearly between the two arm plates along a perpendicular line perpendicular to the two arm plates.

4. The pneumatic pre-rotating wrench according to claim 1, characterized in that, The airflows output by at least two of the air channels act on a single prism surface corresponding to the bolt to be screwed.

5. The pneumatic pre-rotating wrench according to claim 1, characterized in that, The airflow output port of the air channel is a rectangle with a corresponding side length not less than the height of the bolt to be screwed.

6. The pneumatic pre-rotation wrench according to claim 1, characterized in that, The air valve is a high-speed air valve.

7. The pneumatic pre-rotation wrench according to claim 1, characterized in that, A positive pressure air source interface and a negative pressure air source interface respectively corresponding to and communicating with a positive pressure air source and a negative pressure air source are provided at the wrench body, and each of the air valves is respectively communicated with the positive pressure air source interface and the negative pressure air source interface.

8. The pneumatic pre-rotating wrench according to claim 1, wherein A key and a display screen for correspondingly inputting control information and displaying control parameters are embedded at the wrench body and are correspondingly communicatively connected to the microcontroller.

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