High-precision micro plunger pump

Abstract

The utility model relates to a high-precision micro plunger pump which comprises a driving mechanism, a pump head arranged at the upper end of the driving mechanism and a power source arranged on the side edge of the driving mechanism. The driving mechanism comprises a shell, a movable part and a gear which are meshed with each other are arranged on the inner side of the shell, the gear is fixedly arranged on an output shaft of the power source, a plunger is fixedly arranged on the inner side of the upper end of the movable part, and when the output shaft of the power source works, the gear drives the movable part meshed with the gear to move up and down. A plunger at the upper end of the movable part moves up and down along with the movable part and stretches in the pump head to realize discharge and suction; an elastic piece is further arranged between the side wall of the shell and the movable piece so as to eliminate the meshing gap between the movable piece and the gear. According to the plunger pump, the gear and the rack are meshed and matched with the tension spring body, and the tension spring body can eliminate the meshing gap of the gear and the rack, so that the back gap problem of liquid suction and drainage of the pump is eliminated, the precision of the plunger pump is improved, and the situation that the gear and the rack are stuck due to the gap problem is avoided.

Description

Technical Field

[0001] The utility model belongs to the technical field of plunger pumps, and in particular relates to a high-precision micro plunger pump. Background Art

[0002] In the prior art, plunger pumps are generally driven by axial movement of a trapezoidal screw + nut slider, axial movement of a ball screw + nut slider, or axial movement of a screw motor + nut slider. Regardless of whether the transmission is a trapezoidal screw or a ball screw, a certain fitting clearance is required between the sliding screw and the slider, and this fitting clearance includes a mid-diameter clearance and a fitting top clearance. When the thread and the slider thread slide, there is an uncontrollable clearance, resulting in a large backlash of the plunger pump product. In actual use, after pumping the liquid, a certain amount of liquid needs to be reversely discharged with a certain displacement to eliminate the backlash in order to make the discharge accuracy close to the required accuracy. This is time-consuming and increases the action. Moreover, as the number of uses increases, the clearance becomes more unpredictable and the accuracy cannot be guaranteed. Utility Model Content

[0003] Based on this, it is necessary to provide a micro plunger pump that can meet high-precision usage scenarios.

[0004] A high-precision micro-plunger pump comprises a driving mechanism, a pump head arranged at the upper end of the driving mechanism, and a power source arranged at the side of the driving mechanism;

[0005] The driving mechanism comprises a housing, and a movable part and a gear meshing with each other are arranged inside the housing, the gear is fixedly arranged on the output shaft of the power source, and a plunger is fixedly arranged inside the upper end of the movable part. When the output shaft of the power source is working, the movable part meshing with it is driven by the gear to move up and down, and the plunger at the upper end of the movable part moves up and down accordingly, and expands and contracts in the pump head to realize suction and discharge;

[0006] An elastic member is also arranged between the side wall of the shell and the movable member to eliminate the meshing clearance between the movable member and the gear.

[0007] Furthermore, the power source is a stepper motor.

[0008] Furthermore, a Hall sensor is installed on the side of the stepper motor to control the rotation angle of the output shaft of the stepper motor.

[0009] Furthermore, the housing includes a protective cover and a mounting plate which are connected to each other, the pump head is fixed along the outer wall of the upper end of the mounting plate, and the stepper motor is fixed along the side of the mounting plate.

[0010] Furthermore, the inner side wall of the mounting plate and the movable member are also fixedly mounted with slide rails corresponding to each other, and the movable member can move up and down along the slide rails.

[0011] Furthermore, the movable part includes a rack and a sliding connection block which are fixedly connected to each other, and tooth grooves are formed on the side of the rack corresponding to the gear.

[0012] Furthermore, the elastic member includes a first tension spring fixing screw fixedly arranged on the inner side wall of the mounting plate, a second tension spring fixing screw arranged at the front end of the sliding connection block, and a tension spring body is also arranged between the first tension spring fixing screw and the second tension spring fixing screw.

[0013] Furthermore, a water guide groove b is provided on the outer wall of the upper end of the sliding connection block, and a water guide groove a is also connected along the end of the water guide groove b to drain the leaked liquid.

[0014] Furthermore, a connecting end is integrally formed at the lower end of the plunger, and a connecting hole is provided on the inner side of the upper end of the sliding connecting block corresponding to the connecting end. The plunger is inserted along the connecting hole. A pin hole is also provided on the inner side of the sliding connecting block, and a fixing pin is provided on the inner side of the pin hole. A groove is provided along the peripheral side of the connecting end, and the fixing pin abuts against the groove, so that the plunger is fixed to the upper end of the sliding connecting block.

[0015] Technical effects and advantages of the utility model:

[0016] 1. The utility model is provided with a gear rack meshing, and is matched with a tension spring body. The tension spring body can eliminate the gap of the gear rack meshing, thereby eliminating the backlash problem of pump suction and discharge of liquid, improving the accuracy of the plunger pump, and the gear rack will not get stuck due to the gap problem.

[0017] 2. The utility model is designed with a water guide groove. After the plunger leaks, the liquid flows downward along the water guide groove without contacting the motor and the transmission parts, thereby effectively preventing corrosion of electrical components and transmission structures. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 Schematic diagram of the overall structure of a high-precision micro-plunger pump according to an embodiment.

[0019] Figure 2 Schematic diagram of the internal structure of a high-precision micro-plunger pump according to an embodiment.

[0020] Figure 3 It is a schematic diagram of the gear rack meshing transmission structure.

[0021] Figure 4 It is a schematic diagram of the cross-sectional structure of an embodiment.

[0022] Figure 5 It is a schematic diagram of the overall structure of the sliding connection block.

[0023] In the figure: 10, protective cover; 11, sliding connection block; 111, fixing pin; 112, water guide groove a; 113, water guide groove b; 12, rack; 121, tooth groove; 13, slide rail; 14, mounting plate; 15, first tension spring fixing screw; 16, second tension spring fixing screw; 17, tension spring body; 20, stepping motor; 21, gear; 22, Hall sensor; 30, pump head; 31, plunger; 32, connecting end. DETAILED DESCRIPTION

[0024] In order to facilitate the understanding of the present invention, the present invention will be described more comprehensively with reference to the relevant drawings. The drawings provide preferred embodiments of the present invention. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thoroughly and comprehensively understood.

[0025] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementation method.

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0027] Embodiment, the utility model relates to a high-precision micro plunger pump, including a driving mechanism, the upper end of the driving mechanism is connected to a pump head 30, and the side is connected to a stepping motor 20, wherein, Figure 1-2 As shown, the driving mechanism includes an outer protective cover 10, a mounting plate 14 is fixedly arranged on the side of the protective cover 10, the mounting plate 14 is L-shaped, and the pump head 30 and the stepper motor 20 are respectively fixedly arranged on the upper end and the side of the mounting plate 14;

[0028] like Figure 2As shown, a slide rail 13 is fixedly provided on the inner side wall of the mounting plate 14, and a movable part is movably connected along the slide rail 13, and the movable part includes a rack 12, and a gear 21 is provided at the output shaft end of the stepper motor 20, and a tooth groove 121 structure is provided on the side of the rack 12 corresponding to the gear 21. Through the operation of the stepper motor 20, the gear 21 at the output shaft position rotates, and the rack 12 meshing with the gear 21 by the tooth groove 121 moves up and down, and the side wall of the rack 12 away from the mounting plate 14 is also fixedly connected with a sliding connection block 11, as shown in FIG. Figure 3 As shown, a plunger 31 is installed along the upper end of the sliding connection block 11, and the plunger 31 moves as a piston along the inner side of the pump head 30 to play a suction and discharge role;

[0029] like Figure 4 A fixing pin 111 is provided between the plunger 31 and the sliding connection block 11 shown in the figure. A connecting hole is provided at the inner side of the top of the sliding connection block 11 and at the lower end of the plunger 31. The plunger 31 is inserted along the connecting hole. A connecting end 32 is integrally provided at the lower end of the plunger 31. A groove is provided around the connecting end 32. A pin hole is provided on the inner side of the sliding connection block 11 corresponding to the fixing pin 111 for inserting the fixing pin 111. After the fixing pin 111 is inserted, it abuts against the groove of the connecting end 32 to fix the connecting end 32, so that the plunger 31 is fixed to the inner side of the upper end of the sliding connection block 11.

[0030] In addition, in order to eliminate the meshing clearance between the rack 12 and the gear 21, as shown in FIG. Figure 2 As shown, a first tension spring fixing screw 15 is threadedly connected to the inner side wall of the mounting plate 14, and a second tension spring fixing screw 16 is correspondingly fixedly connected to the front end of the sliding connection block 11, and a tension spring body 17 is arranged between the first tension spring fixing screw 15 and the second tension spring fixing screw 16, and the tension spring body 17 is used to eliminate the meshing clearance between the rack 12 and the gear 21;

[0031] Therefore, the rack and pinion transmission structure is compared with the trapezoidal screw or ball screw transmission in the prior art. Since the sliding screw requires a certain matching clearance, this matching clearance includes the middle diameter clearance and the matching top clearance, and the transmission structure in the present application is matched with a tension spring to eliminate the clearance and backlash, and there is no deviation in the forward and reverse reciprocating motion distance, thus meeting the scene of high precision requirements;

[0032] The problem of the plunger pump in the prior art is that the general screw transmission structure has a driving mechanism located at the lower end of the plunger 31. After the plunger 31 leaks, the liquid leaks along the lower end of the plunger 31 to the driving mechanism, thereby causing corrosion. For this purpose, a corrosion-resistant structure is designed, as shown in FIG. Figure 5As shown, a water guide groove b113 is provided along the longitudinal direction of the sliding connection block 11, and a water guide groove a112 is also connected to the end thereof. When the plunger 31 leaks, the leaked liquid flows downward along the water guide groove without contacting the motor and other transmission parts. Only the seal needs to be replaced, which does not affect the product accuracy and life.

[0033] In addition, in order to ensure accuracy, a Hall sensor 22 is provided on one side of the stepper motor 20 , and the rotation angle and displacement of the stepper motor 20 are controlled by the Hall sensor 22 , so as to achieve more accurate positioning.

[0034] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0035] The above-mentioned embodiments only express several embodiments of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. A high-precision micro plunger pump, characterized in that: It comprises a driving mechanism, a pump head (30) arranged at the upper end of the driving mechanism, and a power source arranged at the side of the driving mechanism; The driving mechanism comprises a housing, wherein a movable member and a gear (21) meshing with each other are arranged inside the housing, wherein the gear (21) is fixedly arranged on the output shaft of the power source, and a plunger (31) is fixedly arranged inside the upper end of the movable member. When the output shaft of the power source is working, the movable member meshing with the gear (21) is driven to move up and down, and the plunger (31) at the upper end of the movable member moves up and down accordingly, and expands and contracts in the pump head (30) to realize suction and discharge. An elastic member is also provided between the side wall of the housing and the movable member to eliminate the meshing clearance between the movable member and the gear (21).

2. The high-precision micro-plunger pump according to claim 1, characterized in that: The power source is a stepping motor (20).

3. The high-precision micro-plunger pump according to claim 2, characterized in that: A Hall sensor (22) is installed on the side of the stepper motor (20) for controlling the rotation angle of the output shaft of the stepper motor (20).

4. The high-precision micro-plunger pump according to claim 3, characterized in that: The housing comprises a protective cover (10) and a mounting plate (14) which are connected to each other, the pump head (30) is fixed along the outer wall of the upper end of the mounting plate (14), and the stepping motor (20) is fixed along the side of the mounting plate (14).

5. The high-precision micro-plunger pump according to claim 4, characterized in that: The inner side wall of the mounting plate (14) and the movable part are also fixedly mounted with a slide rail (13) corresponding to the movable part, and the movable part can move up and down along the slide rail (13).

6. The high-precision micro-plunger pump according to claim 5, characterized in that: The movable part comprises a rack (12) and a sliding connection block (11) which are fixedly connected to each other, and tooth grooves (121) are provided on the sides of the rack (12) corresponding to the gear (21).

7. The high-precision micro-plunger pump according to claim 6, characterized in that: The elastic member comprises a first tension spring fixing screw (15) fixedly arranged on the inner side wall of the mounting plate (14), a second tension spring fixing screw (16) arranged at the front end of the sliding connection block (11), and a tension spring body (17) is also arranged between the first tension spring fixing screw (15) and the second tension spring fixing screw (16).

8. The high-precision micro-plunger pump according to claim 7, characterized in that: The outer wall of the upper end of the sliding connection block (11) is provided with a water guide groove b (113), and a water guide groove a (112) is connected along the end of the water guide groove b (113) for draining the leaked liquid.

9. The high-precision micro-plunger pump according to claim 8, characterized in that: The lower end of the plunger (31) is integrally formed with a connecting end (32); a connecting hole is provided on the inner side of the upper end of the sliding connection block (11) corresponding to the connecting end (32); the plunger (31) is inserted along the connecting hole; a pin hole is also provided on the inner side of the sliding connection block (11); a fixing pin (111) is provided on the inner side of the pin hole; a groove is provided along the peripheral side of the connecting end (32); the fixing pin (111) abuts against the groove, so that the plunger (31) is fixed to the upper end of the sliding connection block (11).

Images