Limiting controller

Abstract

The utility model relates to the field of limiters, in particular to a limit controller. Comprising a hollow shell, and a piston rod and a limiting assembly are arranged in the shell. The piston rod moves along the axis of the piston rod under the action of the driving device. The limiting assembly is used for stopping movement of the piston rod when the piston rod moves beyond a preset stroke in the first axial direction or the second axial direction opposite to the first direction. The first limiting mechanism and the second limiting mechanism are used for limiting a piston rod to move in the first direction and the second direction respectively; the first limiting mechanism comprises a first limiting switch and a first trigger matched with the first limiting switch; the second limiting mechanism comprises a second limiting switch and a second trigger matched with the second limiting switch; the first limit switch and the second limit switch are electrically connected with the driving device, and one of the first limit switch and the second limit switch is a b-type contact switch.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of limit stopper, especially relates to a limit controller. BACKGROUND

[0002] The driving device of the electric lifting table adopts a motor to drive a transmission rod to rotate, so as to drive the lifting table leg to lift, and the motor, the transmission rod and the limiting mechanism for limiting the stroke are embedded in the inside of the supporting structure such as the table leg.

[0003] The existing limiting mechanism often has limiting pieces such as pins and buckles which are perpendicular to the movement direction of the table leg, but in order to make the appearance fashionable, some existing electric lifting tables are designed to be relatively thin, and the internal space is also more narrow, so the width size of the table leg cannot accommodate the limiting mechanism in the prior art. Therefore, it is necessary to provide a new type of limiting mechanism to meet the design requirements of the current electric lifting table. SUMMARY

[0004] The utility model aims at providing a limit controller to solve the problem of large size of the limiting mechanism in the prior art.

[0005] The technical scheme of the utility model is as follows: a limit controller comprises a hollow shell, and the shell is provided with:

[0006] A piston rod moves along its own axis under the action of a driving device;

[0007] A limiting assembly is used to stop the movement of the piston rod when the piston rod runs in a first direction or a second direction opposite to the first direction beyond a preset stroke, and comprises a first limiting mechanism and a second limiting mechanism for limiting the movement of the piston rod in the first direction and the second direction respectively;

[0008] The first limiting mechanism comprises a first limit switch and a first trigger matched with the first limit switch;

[0009] The second limiting mechanism comprises a second limit switch and a second trigger matched with the second limit switch;

[0010] The first limit switch and the second limit switch are electrically connected with the driving device, and the first limit switch and the second limit switch are arranged on the same horizontal plane.

[0011] Preferably, the first trigger comprises a pull ring and a pull rod, the pull ring is fixed on the piston rod and moves synchronously with the piston rod, the pull rod has a locking part at one end in the first direction, and the other end abuts against the first limit switch; the pull ring abuts against the locking part after running in the first direction for a preset stroke, drives the pull rod to run in the first direction, and triggers the first limit switch;

[0012] The press mechanism is arranged at one end of the pull rod in the second direction, and the press mechanism gives the pull rod a tendency to move in the second direction, thereby controlling the pull rod to abut against the first limit switch before the pull rod abuts against the locking part.

[0013] Preferably, the pull ring is eccentrically provided with a through hole along the self-axis direction, the pull rod is arranged through the through hole, and the locking part is configured as a step structure at one end of the pull rod in the first direction.

[0014] Preferably, the press mechanism comprises a press head at one end of the pull rod in the second direction, and an elastic member abutting against the press head and coaxially sleeved on the pull rod, one end of the elastic member away from the press head abutting against the shell, and the elastic member giving the pull rod a tendency to move in the second direction.

[0015] Preferably, the second trigger is fixed with the piston rod, and the piston rod abuts against the second limit switch after running a preset stroke in the second direction.

[0016] Preferably, the driving device comprises a servo motor coaxially arranged with the piston rod, a screw rod connected to a driving end of the servo motor, and the piston rod being hollow and threadedly matched with the screw rod.

[0017] Compared with the prior art, the application has the following advantages: in the application, the first limit switch is a b-type contact switch, and the second limit switch is an a-type contact switch, so that when the first trigger and the second trigger connected with the piston rod simultaneously abut against or are separated from the corresponding first limit switch and second limit switch, only one limit switch is triggered, thereby achieving the limit control of the highest stroke and the lowest stroke of the piston rod. BRIEF DESCRIPTION OF DRAWINGS

[0018] The application will be further described below in combination with the drawings and embodiments:

[0019] Figure 1 FIG. 1 is a first perspective view of a limit controller according to the application;

[0020] Figure 2 FIG. 2 is a second perspective view of the limit controller according to the application; Figure 1 FIG. 3 is an enlarged view of A in FIG. 2;

[0021] Figure 3 FIG. 4 is an enlarged view of B in FIG. 2; Figure 1 FIG. 5 is a third perspective view of the limit controller according to the application;

[0022] Figure 4 FIG. 6 is a fourth perspective view of the limit controller according to the application; and

[0023] Wherein: 1, drive device, 11, servo motor, 12, screw rod, 2, piston rod, 3, first limit mechanism, 31, first limit switch, 32, first trigger, 321, pull ring, 322, pull rod, 323, locking part, 324, pressure head, 325, elastic element, 4, second limit mechanism, 41, second limit switch, 42, second trigger. DETAILED DESCRIPTION

[0024] The content of the utility model will be further described in detail in combination with specific embodiments:

[0025] As shown in Figure 1 A limit controller for an electric lifting table, comprising a hollow shell (not shown), a drive device 1, a piston rod 2 and a limit assembly arranged in the shell.

[0026] The drive device 1 comprises a servo motor 11, and the output end of the servo motor 11 is connected with a screw rod 12. The piston rod 2 is hollow and is provided with an internal thread capable of threadedly cooperating with the screw rod 12. The outer wall of the piston rod 2 is provided with a guide block in sliding abutment with the inner wall of the shell, so that the piston rod 2 is driven by the servo motor 11 to perform lifting movement. The tabletop and the supporting leg of the electric lifting table are respectively connected with the piston rod 2 or the drive device 1 at the end away from the screw rod 12, so that the height of the electric lifting table can be adjusted.

[0027] The limit assembly is used to limit the stroke of the piston rod 2. That is, when the piston rod 2 exceeds the preset stroke at any time during the lifting or lowering process, the movement of the piston rod 2 is stopped.

[0028] As shown in Figures 1-4 The limit assembly comprises a first limit mechanism 3 and a second limit mechanism 4. The first limit mechanism 3 is used to limit the highest point of the stroke of the piston rod 2, and comprises a first limit switch 31 and a first trigger 32 arranged in cooperation with the first limit switch 31.

[0029] The first limit switch 31 is a b-type contact switch and is electrically connected with the servo motor 11. The first trigger 32 is arranged directly above the first limit switch 31 and comprises a pull ring 321 and a pull rod 322. The end of the pull rod 322 close to the first limit switch 31 is provided with a pressing mechanism, which comprises a pressing head 324 fixed vertically on the end of the pull rod 322 close to the first limit switch 31 and an elastic member 325 coaxially sleeved on the outer side of the pull rod 322. The elastic member 325 is a spring, and one end of the elastic member 325 abuts against the upper surface of the pressing head 324, and the other end abuts against a stepped structure on the shell. The elastic force of the elastic member 325 acts on the pressing head 324, so that the pull rod 322 has a tendency to run in the second direction, thereby pressing down the first limit switch 31. Since the first limit switch 31 is a b-type contact switch, the first limit switch 31 is not triggered in the current state.

[0030] The pull ring 321 is coaxially fixed on the piston rod 2 and moves up and down with the piston rod 2. The guide block is arranged on the pull ring 321, and the pull ring 321 is eccentrically provided with a through hole in the direction of its own axis, which is used for the pull rod 322 to penetrate. The end of the pull rod 322 in the first direction has a locking portion 323, which is a stepped structure arranged at the end of the pull rod 322 in this embodiment. When the pull ring 321 runs with the piston rod 2 in the first direction to a preset stroke, the pull ring 321 abuts against the locking portion 323, thereby driving the pull rod 322 to move in the first direction against the elastic force of the elastic member 325, and further making the pressing head 324 disengage from the first limit switch 31, triggering the released first limit switch 31, stopping the movement of the servo motor 11, and realizing the limiting of the piston rod 2 in the first direction.

[0031] The second limit mechanism 4 is used for limiting the lowest point of the stroke of the piston rod 2 and comprises a second limit switch 41 and a second trigger 42 matched with the second limit switch 41. The second limit switch 41 is an a-type contact switch and is electrically connected with the servo motor 11.

[0032] The second trigger 42 is fixed with the piston rod 2 and is arranged directly above the second limit switch 41 and moves up and down under the driving of the piston rod 2. When the piston rod 2 runs in the second direction to a preset stroke, the second trigger 42 abuts against the second limit switch 41, triggering the second limit switch 41, stopping the movement of the servo motor 11, and realizing the limiting of the piston rod 2 in the second direction.

[0033] The above examples are only for illustrating the technical concept and characteristics of the present application, and the purpose is to enable those skilled in the art to understand the content of the present application and to implement it, and cannot limit the protection scope of the present application. For those skilled in the art, it is obvious that the present application is not limited to the details of the above exemplary embodiments, and the present application can be implemented in other specific forms without departing from the spirit or basic characteristics of the present application, therefore, from any point of view, the examples should be regarded as exemplary and non-limiting, the scope of the present application is defined by the appended claims rather than the above description, therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present application.

Claims

1. A limit controller, characterized in that, Includes a hollow shell, wherein the shell contains: The piston rod (2) moves along its own axis under the action of the drive device (1); The limiting component is used to stop the movement of the piston rod (2) when the movement of the piston rod (2) in the first axial direction or the second direction opposite to the first direction exceeds the preset stroke. It includes a first limiting mechanism (3) and a second limiting mechanism (4) that restrict the piston rod (2) from moving along a first direction and a second direction respectively; The first limiting mechanism (3) includes a first limiting switch (31) and a first trigger (32) configured in conjunction with the first limiting switch (31); The second limiting mechanism (4) includes a second limiting switch (41) and a second trigger (42) configured in conjunction with the second limiting switch (41); The first limit switch (31) and the second limit switch (41) are electrically connected to the drive device (1), and one of the first limit switch (31) or the second limit switch (41) is a type B contact switch.

2. A limit controller according to claim 1, characterized in that, The first trigger (32) includes a pull ring (321) and a pull rod (322). The pull ring (321) is fixed to the piston rod (2) and moves synchronously with the piston rod (2). The pull rod (322) has a locking part (323) at one end in the first direction and abuts against the first limit switch (31) at the other end. After the pull ring (321) travels a preset distance in the first direction, it abuts against the locking part (323), which drives the pull rod (322) to move in the first direction and triggers the first limit switch (31). The pull rod (322) is provided with a pressing mechanism at one end in the second direction. The pressing mechanism gives the pull rod (322) a tendency to move in the second direction, thereby controlling the pull rod (322) to abut against the first limit switch (31) before the pull rod (322) abuts against the locking part (323).

3. A limit controller according to claim 2, characterized in that, The pull ring (321) has an eccentric perforation along its own axis, the pull rod (322) passes through the perforation, and the locking part (323) is constructed as a stepped structure at one end of the pull rod (322) in the first direction.

4. A limit controller according to claim 3, characterized in that, The pressing mechanism includes a pressure head (324) at one end of the pull rod (322) in the second direction, and an elastic element (325) that abuts against the pressure head (324) and is coaxially sleeved on the pull rod (322). The end of the elastic element (325) away from the pressure head (324) abuts against the housing, and the elastic element (325) gives the pull rod (322) a tendency to move in the second direction.

5. A limit controller according to claim 1, characterized in that, The second trigger (42) is fixed to the piston rod (2). When the piston rod (2) travels a preset stroke in the second direction, it abuts against the second limit switch (41).

6. A limit controller according to claim 1, characterized in that, The drive device (1) includes a servo motor (11) coaxially arranged with the piston rod (2). The drive end of the servo motor (11) is connected to a lead screw (12). The piston rod (2) is hollow inside and threadedly engaged with the lead screw (12).

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