Original point positioning and stroke protecting device of metering pump of filling machine

Abstract

The utility model relates to an original point positioning and stroke protecting device for a metering pump of a filling machine. The original point positioning and stroke protecting device comprises a servo motor, a screw rod, a metering pump base and a pump ejector rod, a vertically-arranged pore plate is fixed to one side of the lead screw, an original point position proximity switch is fixed to the middle position of the pore plate, and an original point position sensing head is fixed to the side, facing the pore plate, of the metering pump base. The original point positioning and stroke protecting device further comprises an upper limiting mechanism and a lower limiting mechanism, and when the metering pump base moves upwards to trigger the upper limiting mechanism or the metering pump base moves downwards to trigger the lower limiting mechanism, the filling machine gives an alarm and stops. By the adoption of the structure, when the metering pump base exceeds the safety stroke, the filling machine can be triggered to give an alarm and stop, and the metering pump base and the lead screw are prevented from being clamped, and a servo motor is prevented from being overloaded; in addition, an original point proximity switch is arranged at the starting point of the metering pump base and used for sensing that the metering pump base returns to the original point position after the filling action is completed, and it is guaranteed that the original point is not lost in the filling process.

Description

Technical Field

[0001] The utility model relates to the technical field of filling equipment, and particularly relates to an origin positioning and stroke protection device for a metering pump of a filling machine. Background Art

[0002] At present, the filling machine in use drives a lead screw through a servo motor. The forward and reverse rotation of the servo motor drives the forward and reverse rotation of the lead screw. The metering pump base is connected to the lead screw through a thread. When the lead screw rotates forward and backward, the metering pump base also moves up and down accordingly to complete the suction and discharge actions of the liquid medicine. The above-mentioned existing technology mainly has the following defects:

[0003] 1. During the operation of the filling machine, the metering pump base moves up and down on the lead screw. After the coupling between the servo motor and the lead screw becomes loose, the filling servo motor still rotates forward and backward according to a fixed program, but it cannot drive the lead screw to move, and the metering pump base does not move either. Without a filling action and without stopping the machine, a large number of empty bottles without filled liquid medicine will be transferred to the conveyor belt.

[0004] 2. When adjusting the filling volume of the filling machine, the metering pump base will move upward to a suitable stroke. The upper limit position is the vertex of the lead screw. After the metering pump base reaches the vertex of the lead screw, it will not be able to move, and continuing to move upward will damage the lead screw or the metering pump.

[0005] 3. During the equipment maintenance process, when maintaining, repairing, or replacing the lead screw and the metering pump base, it is inevitable to disassemble the above components. When installing, it takes a lot of time to debug to accurately determine the origin position again. Summary of the Invention

[0006] The purpose of the utility model is to overcome the deficiencies of the prior art and provide an origin positioning and stroke protection device for a metering pump of a filling machine.

[0007] To achieve the above purpose, the utility model adopts the following technical solutions:

[0008] An origin positioning and stroke protection device for a metering pump of a filling machine includes a servo motor, a lead screw, a metering pump base, and a pump top rod. The metering pump base is in transmission connection with the lead screw through an internal thread, and the pump top rod is fixed vertically on the metering pump base; the servo motor drives the lead screw to rotate forward and backward to drive the metering pump base to move up and down to complete the filling action; a hole plate arranged vertically is fixed on one side of the lead screw, and an origin position proximity switch is fixed at the middle position of the hole plate. An origin position induction head is fixed on the side of the metering pump base facing the hole plate. After the filling action is completed, when the metering pump base moves to a position where the origin position induction head corresponds to the origin position proximity switch, the metering pump base returns to the origin position; the origin positioning and stroke protection device further includes an upper limit mechanism and a lower limit mechanism. When the metering pump base moves upward to trigger the upper limit mechanism or the metering pump base moves downward to trigger the lower limit mechanism, the filling machine alarms and stops.

[0009] Furthermore, the upper limit mechanism includes an upper limit baffle and an upper travel switch. The upper limit baffle is fixed to the upper end of one side of the screw, and the upper travel switch is fixed to the top of the metering pump base. When the metering pump base moves upward beyond the stroke so that the upper travel switch touches the upper limit baffle and is triggered, the filling machine alarms and stops.

[0010] The lower limit mechanism includes a lower limit baffle and a lower stroke switch. The lower limit baffle is fixed to one side of the lower end of the screw rod, and the lower stroke switch is fixed to the bottom of the metering pump base. When the metering pump base moves down beyond the stroke and the lower stroke switch touches the lower limit baffle and is triggered, the filling machine alarms and stops.

[0011] Furthermore, the upper limit mechanism includes an upper limit proximity switch and an upper limit sensing head. The upper limit proximity switch is fixed to the upper end of one side of the orifice plate. The upper limit sensing head is fixed to the side of the metering pump base facing the orifice plate and is located above the origin position sensing head. When the metering pump base moves upward beyond the stroke so that the upper limit sensing head corresponds to the upper limit proximity switch, the filling machine alarms and stops.

[0012] The lower limit mechanism includes a lower limit proximity switch and a lower limit sensing head. The lower limit proximity switch is fixed at the lower end of one side of the orifice plate. The lower limit sensing head is fixed on the side of the metering pump base facing the orifice plate and is located below the origin position sensing head. When the metering pump base moves downward beyond the stroke so that the lower limit sensing head corresponds to the lower limit proximity switch, the filling machine alarms and stops.

[0013] Furthermore, the servo motor is connected to the screw through a coupling.

[0014] The utility model adopts the above technical solution, which has the following beneficial effects:

[0015] 1. In the present invention, the metering pump base moving on the screw is equipped with upper and lower limit mechanisms. When the upper limit mechanism or the lower limit mechanism is triggered, the filling machine alarm stops to prevent the metering pump base and the screw from getting stuck and the servo motor from overloading.

[0016] 2. In the present invention, an origin proximity switch is provided at the starting point of the metering pump base, which is used to sense that the metering pump base returns to the origin position after the filling action is completed, thereby ensuring that the origin is not lost during the filling process. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0018] Figure 1 This is a schematic diagram of Example 1 of the present utility model;

[0019] Figure 2Schematic diagram of Embodiment 2 of the present utility model. Specific embodiments

[0020] As Figure 1-2 shown, an origin positioning and stroke protection device for a metering pump of a filling machine according to the present utility model includes a servo motor 1, a lead screw 2, a metering pump base 3, and a pump ejector rod 4. The metering pump base 3 is in transmission connection with the lead screw 2 through an internal thread, and the pump ejector rod 4 is vertically fixed on the metering pump base 3. The servo motor 1 drives the lead screw 2 to rotate forward and backward through a coupling 5, thereby driving the metering pump base 3 to move up and down to complete the filling operation. A hole plate 6 arranged vertically is fixed on one side of the lead screw 2, and an origin position proximity switch 7 is fixed at the middle position of the hole plate 6. An origin position induction head 8 is fixed on the side of the metering pump base 3 facing the hole plate 6. After the filling operation is completed, when the metering pump base 3 moves to a position where the origin position induction head 8 corresponds to the origin position proximity switch 7, the metering pump base 3 returns to the origin position. The origin positioning and stroke protection device further includes an upper limit mechanism and a lower limit mechanism for preventing the metering pump base 3 from operating beyond the safe stroke. When the metering pump base 3 moves upward to trigger the upper limit mechanism or the metering pump base 3 moves downward to trigger the lower limit mechanism, the filling machine alarms and stops.

[0021] An origin position proximity switch 7 is set corresponding to the origin position of the metering pump base 3 to determine the origin of the metering pump base 3. When the metering pump base 3 moves up and down during the filling process and returns to the origin position each time and is sensed by the origin position proximity switch 7, the controller (PLC) receives the signal sensed by the origin position proximity switch 7, indicating that the origin of the metering pump base 3 is in place and the next round of filling operation can start.

[0022] Embodiment 1, as Figure 1 shown, in this embodiment, the upper and lower limit mechanisms adopt a structure of limit baffles and travel switches. Specifically, the upper limit mechanism includes an upper limit baffle 9 and an upper travel switch 10. The upper limit baffle 9 is fixed at the upper end of one side of the lead screw 2, and the upper travel switch 10 is fixed on the top of the metering pump base 3. When the metering pump base 3 moves upward beyond the stroke and the upper travel switch 10 touches the upper limit baffle 9 and is triggered, the filling machine alarms and stops.

[0023] The lower limit mechanism includes a lower limit baffle 11 and a lower travel switch 12. The lower limit baffle 11 is fixed at one side of the lower end of the lead screw 2, and the lower travel switch 12 is fixed at the bottom of the metering pump base 3. When the metering pump base 3 moves downward beyond the stroke and the lower travel switch 12 touches the lower limit baffle 11 and is triggered, the filling machine alarms and stops.

[0024] Embodiment 2, as Figure 2As shown in the figure, in this embodiment, a proximity switch and a limit induction head are adopted for the upper and lower limit mechanisms. Specifically, the upper limit mechanism includes an upper limit proximity switch 13 and an upper limit induction head 14. The upper limit proximity switch 13 is fixed to the upper end of one side of the orifice plate 6, and the upper limit induction head 14 is fixed to the side of the metering pump base 3 facing the orifice plate 6 and above the origin position induction head 8. When the metering pump base 3 moves upward beyond the stroke so that the upper limit induction head 14 corresponds to the upper limit proximity switch 13, the filling machine will alarm and stop.

[0025] The lower limit mechanism includes a lower limit proximity switch 15 and a lower limit induction head 16. The lower limit proximity switch 15 is fixed to the lower end of one side of the orifice plate 6, and the lower limit induction head 16 is fixed to the side of the metering pump base 3 facing the orifice plate 6 and below the origin position induction head 8. When the metering pump base 3 moves downward beyond the stroke so that the lower limit induction head 16 corresponds to the lower limit proximity switch 15, the filling machine will alarm and stop.

[0026] Compared with Embodiment 1, in Embodiment 2, the upper travel switch 10 is replaced with the upper limit proximity switch 13, and the lower travel switch 12 is replaced with the lower limit proximity switch 15. The upper limit proximity switch 13, the lower limit proximity switch 15, and the origin position proximity switch 7 are all installed on the orifice plate 6, and the original upper limit baffle 9 and lower limit baffle 11 are cancelled. The upper limit induction head 14, the lower limit induction head 16, and the origin position induction head are installed on the same side of the metering pump base 3, corresponding one by one to the upper limit proximity switch 13, the lower limit proximity switch 15, and the origin position proximity switch 7 installed on the orifice plate 6.

[0027] In contrast, the structure of Embodiment 2 is simpler than that using a travel switch to trigger the limit. There is no wire structure on the upper limit induction head 14 and the lower limit induction head 16, and the phenomenon that the wire of the travel switch is wound around the lead screw 2 will not occur.

[0028] The specific implementation manners of the present utility model have been described above. However, those skilled in the art should understand that this is only an example. Without departing from the principle and essence of the present utility model, those skilled in the art can make various changes or modifications to this implementation manner, but these changes and modifications all fall within the protection scope of the present utility model.

Claims

1. An origin positioning and stroke protection device for a metering pump of a filling machine, comprising a servo motor, a lead screw, a metering pump base and a pump top rod. The metering pump base is in transmission connection with the lead screw through an internal thread, and the pump top rod is vertically fixed on the metering pump base; the servo motor drives the lead screw to rotate forward and backward to drive the metering pump base to move up and down to complete the filling action; it is characterized in that: A vertically arranged orifice plate is fixed on one side of the screw rod, an origin position proximity switch is fixed in the middle position of the orifice plate, and an origin position sensing head is fixed on the side of the metering pump base facing the orifice plate. After the filling action is completed, the metering pump base moves to the origin position. When the sensing head corresponds to the origin position proximity switch, the metering pump base returns to the origin position; the origin positioning and stroke protection device also includes an upper limit mechanism and a lower limit mechanism. When the metering pump base moves up to trigger the upper limit mechanism or the metering pump base moves down to trigger the lower limit mechanism, the filling machine alarms and stops.

2. The origin positioning and stroke protection device of a metering pump for a filling machine according to claim 1, characterized in that: The upper limit mechanism includes an upper limit baffle and an upper travel switch. The upper limit baffle is fixed to the upper end of one side of the screw, and the upper travel switch is fixed to the top of the metering pump base. When the metering pump base moves up beyond the stroke so that the upper travel switch touches the upper limit baffle and is triggered, the filling machine alarms and stops. The lower limit mechanism includes a lower limit baffle and a lower stroke switch. The lower limit baffle is fixed to one side of the lower end of the screw rod, and the lower stroke switch is fixed to the bottom of the metering pump base. When the metering pump base moves down beyond the stroke and the lower stroke switch touches the lower limit baffle and is triggered, the filling machine alarms and stops.

3. The origin positioning and stroke protection device of a metering pump for a filling machine according to claim 1, characterized in that: The upper limit mechanism includes an upper limit proximity switch and an upper limit sensing head. The upper limit proximity switch is fixed to the upper end of one side of the orifice plate. The upper limit sensing head is fixed to the side of the metering pump base facing the orifice plate and is located above the origin position sensing head. When the metering pump base moves upward beyond the stroke so that the upper limit sensing head corresponds to the upper limit proximity switch, the filling machine alarms and stops. The lower limit mechanism includes a lower limit proximity switch and a lower limit sensing head. The lower limit proximity switch is fixed at the lower end of one side of the orifice plate. The lower limit sensing head is fixed on the side of the metering pump base facing the orifice plate and is located below the origin position sensing head. When the metering pump base moves downward beyond the stroke so that the lower limit sensing head corresponds to the lower limit proximity switch, the filling machine alarms and stops.

4. The origin positioning and stroke protection device of a metering pump for a filling machine according to claim 1, characterized in that: The servo motor is connected to the screw through a coupling.

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