CN216044253U

CN216044253U - Diaphragm vacuum pump

Info

Publication number: CN216044253U
Application number: CN202120421782.1U
Authority: CN
Inventors: 张成祥
Original assignee: Shinetek Instruments Research Institute
Current assignee: Shinetek Instruments Research Institute
Priority date: 2021-02-25
Filing date: 2021-02-25
Publication date: 2022-03-15
Anticipated expiration: 2031-02-25

Abstract

The present disclosure describes a diaphragm vacuum pump comprising: a main shaft for connecting to an output shaft of a drive motor; one or more pump head groups; wherein each said pump head set comprises four pump heads evenly spaced about a longitudinal central axis of said main shaft in a plane perpendicular to said central axis, each said pump head being equidistant from said central axis; a pump chamber is provided in each pump head, a diaphragm membrane is provided in the pump chamber, the diaphragm membrane is connected to the main shaft via an eccentric crank, and the rotary motion of the main shaft drives the diaphragm membrane to reciprocate.

Description

Diaphragm vacuum pump

Technical Field

The present disclosure relates to a diaphragm vacuum pump.

Background

The basic principle of the diaphragm vacuum pump is that a motor drives a diaphragm to reciprocate in a pump cavity through a mechanical mechanism, and the one-way valves on the air inlet side and the air outlet side of the pump cavity are utilized to realize the conveying process of air under low pressure, so that the aim of forming vacuum is fulfilled.

The simplest diaphragm vacuum pump uses a motor to drive a diaphragm pump head unit. The motor main shaft drives the crank installed on the cam through the rotation of an eccentric cam to carry out reciprocating motion, the tail end of the crank is generally installed at the center of a diaphragm, the periphery of the diaphragm forms a pump cavity through a compression sealing mode and a pump head above the diaphragm, the air inlet cavity and the air outlet cavity are respectively connected with pipelines of an air inlet and an air outlet, one-way valves in opposite directions are respectively arranged between the air inlet cavity and the air outlet cavity and between the air outlet cavity and the diaphragm cavity, and therefore in the process that the diaphragm continuously compresses and expands air in the diaphragm cavity, and the transportation of air from the air inlet cavity to the air outlet cavity is achieved. The strong torque of the motor can make the movement of the diaphragm be carried out under the vacuum low pressure, thereby achieving the purpose of forming vacuum. When the diaphragm pump needs to increase the flow, also further reduce the vacuum simultaneously, people begin to use the series connection between the pump head to improve vacuum, use parallelly connected speed that increases to bleed between the pump head. On the premise that the sizes of the pump heads and the diaphragms are not changed, increasing the number of the pump heads is obviously a direct method for realizing a large flow or obtaining a higher vacuum degree pump.

For this purpose, some diaphragm vacuum pumps use a motor with two output shafts, two pump heads are mounted on the same side of the two ends of the motor, or two opposite pump heads can be mounted on the two sides of the shaft of the motor with a single output shaft.

For example, CN105003426A relates to a diaphragm vacuum pump, which discloses a pump having an output shaft at both ends of a motor, and two pump heads distributed on one side of a motor shaft. The structure of the pump disclosed in CN203742958U and CN104976105A is that two pump heads are installed on two opposite sides of a main shaft. The two structures must take the problem of centrifugal force generated in the operation process into consideration, so a balance block is usually arranged on a shaft to ensure the moment balance of the pump in the operation process, thereby realizing the smooth start of the pump and eliminating the phenomenon of shaking. Such a configuration occupies relatively more space, increasing the overall weight and volume of the pump, as well as increasing the power required to operate the pump.

SUMMERY OF THE UTILITY MODEL

To at least partially overcome the above-mentioned problems of the prior art, the present disclosure provides a diaphragm vacuum pump that can reduce the vibration of the pump and does not require a balance weight to be mounted on a main shaft.

According to an aspect of an embodiment of the present disclosure, there is provided a diaphragm vacuum pump including: a main shaft for connecting to an output shaft of the driving motor; one or more pump head groups; wherein each pump head set comprises four pump heads evenly spaced around a longitudinal central axis of the main shaft in a plane perpendicular to the longitudinal central axis, each pump head being equidistant from the longitudinal central axis of the main shaft; a pump chamber is provided in each pump head, a diaphragm membrane is provided in the pump chamber, the diaphragm membrane is connected to the main shaft via an eccentric crank, and the rotary motion of the main shaft drives the diaphragm membrane to reciprocate. The reciprocating movement of the diaphragm membrane in the pump chamber performs the function of delivering an air flow, creating a vacuum.

In some embodiments according to the present disclosure, the two pump heads of each pump head set that are oppositely disposed are disposed in a plane perpendicular to the longitudinal central axis of the main shaft to counteract a centrifugal force when the two pump heads that are oppositely disposed are operated. And possible displacement of the pump due to vibration during operation can be prevented.

In some embodiments according to the present disclosure, a plurality of eccentrics are arranged side by side on the main shaft. The main shaft is driven by the driving motor to rotate and drive the eccentric wheel to eccentrically rotate.

In some embodiments according to the present disclosure, two eccentrics corresponding to two oppositely disposed pump heads are arranged adjacent to each other.

In some embodiments according to the present disclosure, the eccentric crank is rotatably mounted via a bearing on an eccentric of the main shaft, the rotational motion of the main shaft driving the diaphragm membrane to reciprocate via the eccentric crank.

In some embodiments according to the present disclosure, an end of the eccentric crank is connected to a center of the diaphragm membrane.

In some embodiments according to the present disclosure, the outlet lines of the plurality of pump head groups are convergently connected to the outlet air homogenizer, and the inlet lines are convergently connected to the inlet air homogenizer.

In some embodiments according to the present disclosure, a plurality of pump head groups are connected to each other in series and/or in parallel.

In some embodiments according to the present disclosure, the individual pump heads of each pump head group are connected to each other in series and/or in parallel.

In some embodiments according to the present disclosure, the pipes of the air inlets of some of the plurality of pump head groups are convergently connected to the air inlet homogenizing distributor, and the air outlets are connected to the flow dividing air outlets; and the air inlets of other pump head groups in the plurality of pump head groups are connected to the flow dividing air outlet, the flow dividing air outlet is connected with the air outlet uniform distributor through a one-way valve, and the air outlet pipelines of the other pump head groups are converged with the outlets of the air outlet uniform distributor.

The disclosed diaphragm vacuum pump reduces the vibration of the pump by providing four pump heads evenly spaced about a longitudinal central axis in a plane perpendicular to the longitudinal central axis of the main shaft, and the moments of force between the pump heads can be balanced during operation without the need for a counterweight to be mounted on the main shaft.

Drawings

FIG. 1 is a cross-sectional view of a diaphragm vacuum pump according to the present disclosure in a direction parallel to a main shaft;

FIG. 2 is a cross-sectional view of the diaphragm vacuum pump of FIG. 1 taken along line C-C;

FIG. 3 is a perspective view of a spindle according to the present disclosure;

FIG. 4 is a plan view of the spindle of FIG. 3;

FIG. 5 is a cross-sectional view through the longitudinal central axis of the spindle taken perpendicular to the direction A-A in FIG. 4;

fig. 6 illustrates one embodiment of a pump head connection according to the present disclosure.

Detailed Description

The diaphragm vacuum pump disclosed in the present invention will be described in further detail with reference to the accompanying drawings and specific embodiments. Advantages and features of the present invention will become apparent from the following detailed description and claims. It is noted that the drawings are in greatly simplified form and that non-precision ratios are used for convenience and clarity only to aid in the description of the embodiments of the utility model.

Referring to the drawings, figures 1 and 2 show a diaphragm vacuum pump according to the present disclosure, comprising a drive motor 1, a main shaft 2 connected to an output shaft of the drive motor 1, and one or more pump head groups 3. For example, the diaphragm vacuum pump may comprise two pump head groups 3.

The driving motor 1 may be an ac single-phase asynchronous motor, a variable frequency motor, or a high-power dc brushless motor. The drive motor 1 may be built into the diaphragm vacuum pump arrangement or external to the diaphragm vacuum pump. The external design of the driving motor 1 can have higher flexibility, and the adoption of the motor with explosion prevention or high protection level can enable the pump to be integrally adapted to various severe working environments, such as underground mine environments and the like.

The main shaft 2 may be mounted on an output shaft of the drive motor 1 by a coupling device (e.g., a shaft coupling) and rotate integrally with the output shaft.

Each pump head set 3 comprises four pump heads 4 evenly spaced around the main shaft 2, i.e. each pump head 4 is evenly arranged at 90 degree angular intervals around the longitudinal centre axis X-X of the main shaft 2, and each pump head 4 is at an equal distance from the longitudinal centre axis of the main shaft 2. As shown in fig. 2, each pump head 4 is spaced from each other by an angle of 90 degrees in a projection of a plane perpendicular to the longitudinal center axis of the main shaft 2 and passing through the line C-C.

A pump chamber is provided in each pump head 4, the pump heads 4 defining the size of the pump chamber, and a diaphragm membrane 7 is provided in the pump chamber. The membrane 7 is pressure-tight sealed against the pump chamber inner wall, the membrane 7 being connected to the main shaft 2 via an eccentric crank 5, e.g. the eccentric crank 5 is preferably connected to the membrane 5 at its center. The connection of the main shaft 2 to the eccentric crank 5 is configured such that a rotational movement of the main shaft 2 drives a reciprocating movement of the eccentric crank 5, and thus of the diaphragm membrane 7. The pump cavity where the diaphragm membrane 7 is located is provided with a double-chamber pump cavity with a one-way valve, and the functions of conveying airflow and forming vacuum are realized in the reciprocating motion of the diaphragm membrane 7.

An eccentric crank 5 is mounted to the main shaft 2 via a bearing 6. The main shaft 2 drives the eccentric crank 5 to reciprocate when being driven by the driving motor 1 to rotate, and the reciprocating operation of the eccentric crank 5 drives the diaphragm membrane 7 to reciprocate in the pump cavity in the direction vertical to the longitudinal central axis of the main shaft 2, so that the volume of an air cavity formed by the diaphragm membrane 7 and the pump head 4 is changed. The eccentric cranks 5 associated with the oppositely disposed pump heads 4 are preferably arranged symmetrically in places, so that the centrifugal forces generated by the moving eccentric cranks 5 during operation of the two pump heads arranged opposite one another can be counteracted and a possible displacement of the pump due to vibrations during operation can be prevented.

Referring to fig. 3-5, perspective, plan, and cross-sectional views of a spindle 2 according to the present disclosure are shown. The main shaft 2 is provided with a plurality of eccentric wheels 8 arranged in parallel. The main shaft 2 is driven by the driving motor 1 to rotate and drive the eccentric wheel 8 to rotate eccentrically. The bearing 6 is rotatably mounted on an eccentric 8 and the eccentric crank 5 is rotatably mounted on the eccentric 8 of the main shaft 2 via the bearing 6, such that the rotary motion of the main shaft 2 drives the diaphragm membrane 7 to reciprocate via the eccentric crank 5. The eccentrics 8 corresponding to a single pump head group 3 are preferably spaced apart from each other by an equal distance along the longitudinal centre axis. And preferably also two eccentric wheels 8 arranged opposite each other are adjacent to each other, respectively two eccentric cranks 5 corresponding to the pump heads 4 arranged opposite each other are mounted on the two adjacent eccentric wheels 8, respectively. The eccentric rotational movement of the eccentric 8 drives the eccentric crank 5 to reciprocate in a plane perpendicular to the longitudinal central axis.

Each pump head 4 is arranged evenly at 90-degree angular intervals around the main shaft 2, so that each pump head set 3 comprises two pairs of pump heads 4 oppositely arranged at 180-degree angles around the main shaft 2, i.e. symmetrically arranged with respect to the longitudinal central axis of the main shaft 2 in a plane perpendicular to this central axis. Correspondingly, the eccentric cranks 5 and the diaphragm membranes 7 are also arranged evenly at intervals of 90 degrees around the main shaft 2, the eccentric cranks 5 and the diaphragm membranes 7 also being arranged symmetrically relative to the longitudinal center axis of the main shaft 2 in a plane perpendicular to this center axis. In this way, the pump heads 4, the eccentric cranks 5 and the diaphragm diaphragms 7 are arranged in a pairwise symmetrical manner, so that when each pump head 4 operates, the acting moments acting on the main shaft 2 are balanced with each other, and therefore, an eccentric balancing weight does not need to be additionally installed, thereby reducing the vibration in the operation process of the pump, improving the operation efficiency of the pump, and reducing the overall weight of the pump.

Specifically, for example, four eccentric cranks 5 are compactly mounted on the main shaft 2 for each pump head group 3, two pump heads 4 are respectively mounted on

planes

11, 12 perpendicular to the longitudinal central axis, and the four pump heads 4 are equidistant from the longitudinal central axis; likewise, for the second pump head set 3, two pump heads 4 are mounted on

planes

13, 14 perpendicular to the longitudinal central axis, respectively, and the four pump heads 4 are equidistant from the longitudinal central axis. Each pump head 4 can play the effect of air extraction, can be connected to each other through the combination mode of establishing ties and parallelly connected between each pump head 4 to reach the requirement of required air extraction speed and vacuum.

The connection between the pump heads will be briefly described below with reference to fig. 1 and 6. The outlet lines of the plurality of pump head groups 3 may be convergingly connected to the outlet air homogenizer, and the inlet lines may be convergingly connected to the inlet air homogenizer. Specifically, as an example, the pipelines of the air inlets of the

pump head groups

31, 32, 33 are convergently connected to the air inlet homogenizing distributor 61, the air outlets of the

pump head groups

31, 32, 33 are connected to the divided air outlets 62, the air inlet of the pump head group 34 is connected to the divided air outlets 62, the divided air outlets 62 are connected through the check valve 63 and the air outlet homogenizing distributor 64, and the pipelines of the air outlet of the pump head group 34 are convergently connected with the outlet of the air outlet homogenizing distributor 64. The connection mode is to achieve the purposes of balancing air flow and maximally playing the air suction function of each pump head. Meanwhile, the condition that the load of individual pump heads is overlarge is avoided, and the balanced application of the pump head efficiency is realized. The modular design is beneficial to the mass production of products.

In particular embodiments, the pump head groups may be connected to each other in series and/or in parallel, e.g. the

pump head groups

31, 32, 33, 34 are connected in series. It will be appreciated that the connections between the pump heads and between the pump head sets may be modified accordingly, depending on the required pumping speed and vacuum requirements, and are not limited to the particular connections shown in the drawings.

The disclosed diaphragm vacuum pump, due to the uniform design of the pump heads 4, allows the moments of force between the pump heads 4 to be balanced during operation without the need for a balancing block structure as is necessary with prior art single pump heads or 180 degree oppositely mounted pump heads. The problem of shaking and deviation of the pump body in the running process is solved because of the balance of the moment, and the pump body with the pump heads on the whole periphery can be installed in a supporting mode. A pump body of compact construction can be obtained, for example, the size of a pump body with eight pump heads is greatly reduced compared to a 180 degree pump head mounting with two end spigots. Most of the pump body is of a metal structure, so that the weight of the whole pump is greatly reduced, and the pump which is compact and light and has high performance index can be formed.

In the description of the present disclosure, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of describing the present invention and simplifying the description, but 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 limiting the present invention.

In addition, the technical features involved in the different embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

As used in this disclosure and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term "and/or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

The terms "plurality" and "a plurality" in the present disclosure and appended claims refer to two or more than two unless otherwise specified.

It will be apparent to those skilled in the art that various changes and modifications can be made in the diaphragm vacuum pump disclosed in the present invention without departing from the spirit and scope of the utility model. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

Claims

1. A diaphragm vacuum pump, comprising:

a main shaft for connecting to an output shaft of a drive motor;

one or more pump head groups;

wherein each said pump head set comprises four pump heads, said four pump heads being evenly spaced about said central longitudinal axis in a plane perpendicular to said central longitudinal axis of said main shaft, each said pump head being equidistant from said central longitudinal axis of said main shaft;

a pump chamber is provided in each pump head, a diaphragm membrane is provided in the pump chamber, the diaphragm membrane is connected to the main shaft via an eccentric crank, and the rotary motion of the main shaft drives the diaphragm membrane to reciprocate.

2. A diaphragm vacuum pump according to claim 1, wherein the two oppositely disposed pump heads in each pump head set are disposed in a plane perpendicular to the central longitudinal axis of the main shaft to counteract centrifugal forces when the two oppositely disposed pump heads are in operation.

3. A diaphragm vacuum pump according to claim 1, wherein the main shaft is provided with a plurality of eccentrics arranged in parallel.

4. A diaphragm vacuum pump according to claim 3, wherein the eccentric crank is rotatably mounted via a bearing on an eccentric of the main shaft, the rotary motion of the main shaft driving the diaphragm membrane to reciprocate via the eccentric crank.

5. A diaphragm vacuum pump according to claim 4, wherein two eccentrics corresponding to two oppositely disposed pump heads are arranged adjacent to each other.

6. A diaphragm vacuum pump according to claim 1, wherein the end of the eccentric crank is connected to the centre of the diaphragm membrane.

7. A diaphragm vacuum pump according to claim 1, wherein the outlet gas lines of the plurality of groups of pump heads are convergingly connected to an outlet gas distributor and the inlet gas lines are convergingly connected to an inlet gas distributor.

8. A diaphragm vacuum pump according to claim 7, wherein the plurality of groups of pump heads are connected to each other in series and/or in parallel.

9. A diaphragm vacuum pump according to claim 7, wherein the individual pump heads of each pump head group are connected to each other in series and/or in parallel.

10. A diaphragm vacuum pump according to claim 8 or 9, wherein:

pipelines of air inlets of some pump head groups in the plurality of pump head groups are connected to the air inlet uniform distributor in a gathering mode, and air outlets are connected to the flow dividing air outlets;

the air inlets of other pump head groups in the plurality of pump head groups are connected to the flow dividing air outlet, the flow dividing air outlet is connected with the air outlet uniform distributor through a one-way valve, and the air outlet pipelines of the other pump head groups are converged with the outlets of the air outlet uniform distributor.