Patent Description:
In general, a vacuum ejector pump that is a device used in a vacuum transfer system includes an ejector main body including multi-stage nozzles arranged in series, a through-hole defined in a sidewall of the main body, and a flexible valve installed inside the through-hole. Particularly, a small-sized vacuum ejector pump is directly mounted to the inside of a housing that requires exhaustion. Here, a vacuum chamber in the housing communicates with the through-hole. Also, a separate suction device, e.g., a suction cup or pad, is connected to the vacuum chamber to constitute the vacuum system.

When the compressed air supplied while the system operates is discharged by passing through the ejector main body at a high speed, the air in the vacuum chamber is introduced into the main body through the through-hole and discharged together with the compressed air. Thus, a vacuum and a negative pressure are generated in the vacuum chamber and the suction device, and when the generated negative pressure is equal to or less than a predetermined level, the through-hole is closed by a valve, and the vacuum chamber maintains the predetermined level. The negative pressure in the suction device generated in this process is used for gripping and transferring a product.

Each of <CIT> (<CIT>) and <CIT>discloses a typical vacuum ejector pump. The former discloses a vacuum ejector pump in which a plurality of nozzles are assembled in a state of being arranged parallel in one direction, and a valve component is installed between the nozzles, and the latter discloses a vacuum ejector pump in which nozzles are assembled by using a separate cylindrical member. <CIT> discloses a vacuum pump wherein the surrounding space communicates differently with the nozzles as claimed in claim <NUM>. Further, the nozzles are assembled differently.

Currently, the above-disclosed devices are substantially used in a working site of vacuum transferring. However, all of the devices have.

Furthermore, in case of the latter,
production and assembly are complex and uneconomical due to a lot of components.

The present invention is suggested to solve the above-described problems of the typical vacuum ejector pumps. The present invention provides a vacuum ejector pump that is easily assembled and manufactured, maintains a rigid and stable state, and minimizes vacuum leakage.

The present invention provides a vacuum ejector pump including a plurality of nozzles, which are assembled, and activated by compressed air passing through the nozzles at a high speed to generate a negative pressure in an outer surrounding space,
the vacuum ejector pump including:.

Here, the compressed air is introduced to the first nozzle, passes the intermediate nozzle, and then discharged to the outside through the second nozzle.

Preferably, the through-hole may pass through each of the cover parts.

Also, the intermediate nozzle may include a ring-shaped stopper flange formed on an outer circumference of a central portion of the intermediate nozzle, and ends of the front-cover part and the rear-cover part may be in contact with both side surfaces of the flange to face each other, respectively.

The ejector main body may include a mutual hook structure disposed between the intermediate nozzle and each of the cover parts to prevent each of the nozzles that are assembled from arbitrarily rotating. Specifically, the hook structure may be a 'key-key groove' corresponding structure, and the key groove and the key are disposed on ends of the flange and the cover parts, respectively, so that the key groove and the key correspond to each other.

The vacuum ejector pump of the present invention may further include a flexible valve member installed in the ejector main body and configured to open and close the through-hole. Preferably, the valve member may be installed in a space between each of the cover parts of the first and second nozzles and the intermediate nozzle disposed between the first and second nozzles.

Specifically, the valve member may include: an O-ring inserted and fixed to an outer circumference of the intermediate nozzle; and a check valve flap extending from the O-ring to cover the through-hole. Preferably, the valve flap may include a sealing circle protruding a surface of the valve flap in the form of surrounding the through-hole.

The vacuum ejector pump according to the present invention basically has the structure in which the cover parts of the first nozzle and the second nozzle are symmetrically inserted to both side ends of the intermediate nozzle, and this structure is easily assembled, simple, and rigid in comparison with other pump devices.

Preferably, the valve member is integrated with the O-ring and inserted to the intermediate nozzle. In this case, the valves may be easily configured and assembled and effectively block the unnecessary flow of the air to minimize the vacuum leakage of the device.

Characteristics and effects of the 'vacuum ejector pump' of the present invention, which are described or not described above, will be clarified through embodiments described below with reference to the accompanying drawings. In <FIG>, a reference numeral '<NUM>' indicates the vacuum ejector pump according to an embodiment of the present invention.

Referring to <FIG>, a vacuum ejector pump <NUM> of the present invention is a device including a plurality of nozzles <NUM>, <NUM>, and <NUM> arranged in series and activated by compressed air passing through the nozzles <NUM>, <NUM>, and <NUM> at a high speed to exhaust an outer surrounding space (refer to 'S' of <FIG>), thereby generating a negative pressure therein, like a typical vacuum ejector pump. Specifically, the vacuum ejector pump <NUM> includes an ejector main body <NUM> including a pipe-type intermediate nozzle <NUM> having a channel in a longitudinal direction (a horizontal direction in the drawing) and first and second nozzles <NUM> and <NUM> that are respectively assembled to both sides of the intermediate nozzle <NUM>.

Reference numeral <NUM> indicates a compressed air inlet defined in the first nozzle <NUM>, and reference numeral <NUM> indicates an outlet defined in the second nozzle <NUM>. The compressed air is supplied to the first nozzle <NUM>, passes through the intermediate nozzle <NUM>, and then discharged to the outside through the second nozzle <NUM>.

Specifically, the first nozzle <NUM> is integrated with a front-cover part <NUM> inserted to an outer circumference of one end 16a of the intermediate nozzle <NUM>, and the second nozzle <NUM> is integrated with a rear-cover part <NUM> inserted to an outer circumference of the other end 16b of the intermediate nozzle <NUM>. That is, the front-cover part <NUM> and the rear-cover part <NUM> are inserted and assembled in opposite directions (refer to arrows ① and (<NUM>) of <FIG>) while respectively accommodating the both ends 16a and 16b of the intermediate nozzle <NUM>, thereby constituting the ejector main body <NUM> including the three nozzles <NUM>, <NUM>, and <NUM>.

The above-described structure of the ejector main body <NUM> is easily assembled, simple, rigid, and stable in comparison with a typical other nozzle structures.

Here, the surrounding space S communicates with each of the nozzles <NUM>, <NUM>, and <NUM> a through-hole <NUM> defined in a sidewall of the ejector main body <NUM> and a slot <NUM> formed between channels of the nozzles <NUM>, <NUM>, and <NUM>. The slot <NUM> serves as a passage that allows the through-hole <NUM> to communicate with each of the nozzles <NUM>, <NUM>, and <NUM>. However, the embodiment of the present invention is not limited to the specific name or shape thereof. The through-hole <NUM> passes through each of the cover parts <NUM> and <NUM> for convenience of processing.

The intermediate nozzle <NUM> includes a ring-shaped stopper flange <NUM> formed on an outer circumference of a central portion thereof for convenience of assembly of the ejector main body <NUM>, and thus the front-cover part <NUM> and the rear-cover part <NUM> are inserted such that ends thereof respectively contact both opposite side surfaces of the flange <NUM>.

The ejector main body <NUM> further includes a mutual hook structure <NUM> formed between the intermediate nozzle <NUM> and each of the cover parts <NUM> and <NUM> to prevent an arbitrary rotation of each of the assembled nozzles <NUM>, <NUM>, and <NUM>. Specifically, the mutual hook structure <NUM> has a 'key <NUM> - key groove <NUM>' structure, and preferably corresponds to the flange <NUM> and the end of each of the cover parts <NUM> and <NUM>.

The vacuum ejector pump <NUM> of the present invention further includes a flexible valve member <NUM> installed in the ejector main body <NUM> to open and close the through-hole <NUM>. Preferably, the valve member <NUM> is installed in a space between each of the cover parts <NUM> and <NUM> of the first and second nozzles <NUM> and <NUM> and each of the ends 16a and 16b of the intermediate nozzle <NUM> disposed therebetween.

Specifically, the valve member <NUM> includes an O-ring <NUM> inserted to the outer circumference of the intermediate nozzle <NUM> and a check valve flap <NUM> extending from the O-ring <NUM> to cover the through-hole <NUM>. Preferably, the valve flap <NUM> includes a sealing circle <NUM> protruding from a surface thereof in the form of surrounding the through-hole <NUM>.

When the vacuum ejector pump <NUM> of the present invention is assembled, the valve member <NUM> is firstly installed at the end 16a and 16b of the intermediate nozzle <NUM>, and then the groove <NUM> and the key <NUM> are aligned while inserting the cover parts <NUM> and <NUM> of the first and second nozzles <NUM> and <NUM> to both sides of the intermediate nozzle <NUM> in opposite directions (refer to arrows ① and (<NUM>) of <FIG>), so that the valve flap <NUM> naturally covers the through-hole <NUM>.

Referring to <FIG>, the vacuum ejector pump <NUM> of the present invention is mounted to the inside of a separately provided housing H and exhaust the surrounding space S, i.e., a vacuum chamber in the housing H. For example, a suction device communicating with the surrounding space S such as a suction cup or pad may be connected to the housing H. Firstly, a high speed compressed air is supplied to the inlet <NUM> of the first nozzle <NUM>, passes through the intermediate nozzle <NUM>, and discharged to the outside through the outlet of the third nozzle (refer to an arrow (<NUM>)).

In this process, pressure drop is generated in the slot <NUM> between the nozzles <NUM>, <NUM>, and <NUM>, and the valve flap <NUM> operates to open the through-hole <NUM>. In this state, the surrounding space S is exhausted. That is, the air in the surrounding space S is introduced into the ejector main body <NUM> through the through-hole <NUM> and the slot and discharged to the outside together with the compressed air (refer to an arrow ④). This exhausting process generates a vacuum and a negative pressure in the surrounding space S and the suction device.

Thus, when an inner pressure level of the surrounding space S is equal to an inner pressure level of the ejector main body <NUM>, the valve flap <NUM> operates reversely to close the through-hole <NUM>. Thus, the vacuum and the negative pressure are generated and maintained in the inside of the surrounding space S and the suction device, and the vacuum transfer system may grip and transfer a product by using the generated negative pressure.

Here, when sealing between the through-hole <NUM> and the valve member <NUM> is weak, the air may be introduced into the surrounding space S through the through-hole <NUM> to instantly break the generated vacuum and negative pressure, and thus a transferring product may be dropped. In order to prevent this limitation, in a case, the compressed air may be continuously supplied. However, in this case, a huge energy loss may be generated. In another case, various kinds of sealing components may be used. However, this case may cause inconvenience and complexity, and an effect thereof is insignificant.

Claim 1:
A vacuum ejector pump comprising a plurality of nozzles, which are assembled, and activated by compressed air passing through the nozzles at a high speed to generate a negative pressure in an outer surrounding space (S), the vacuum ejector pump comprising:
a pipe-type intermediate nozzle (<NUM>) having a longitudinal-direction channel;
a first nozzle (<NUM>) on which a front-cover part (<NUM>) inserted to an outer circumference of one end (16a) of the intermediate nozzle (<NUM>) is formed; and
a second nozzle (<NUM>) on which a rear-cover part (<NUM>) inserted to an outer circumference of the other end (16b) of the intermediate nozzle (<NUM>) to face the front-cover part (<NUM>) is formed;
wherein the intermediate nozzle (<NUM>) is disposed between the first nozzle (<NUM>) and the second nozzle (<NUM>),
the intermediate nozzle (<NUM>), the first nozzle (<NUM>) and the second nozzle (<NUM>) constitute an ejector main body (<NUM>), and
the surrounding space (S) communicates with each of the nozzles (<NUM>, <NUM>, <NUM>) through a through-hole (<NUM>) defined in a sidewall of the ejector main body (<NUM>) and a slot (<NUM>) defined between the nozzles (<NUM>, <NUM>, <NUM>).