GB2032830A

GB2032830A - A suction pick up tool

Info

Publication number: GB2032830A
Application number: GB7922595A
Authority: GB
Original assignee: SECR DEFENCE; UK Secretary of State for Defence
Current assignee: SECR DEFENCE; UK Secretary of State for Defence
Priority date: 1978-08-05
Filing date: 1979-06-28
Publication date: 1980-05-14

Abstract

A venturi 8a, 9, 8b, connects an inlet duct 7 and a closable outlet duct 2 in the vicinity of a first end of a working duct 5 such that, in use, a reduction or increase in fluid pressure occurs at the second end of the working duct when the outlet duct is correspondingly open or closed to enable the tool to pick up or deposit an article. The suction tool is particularly applicable to the manipulation of electronic components or to biomedical applications. <IMAGE>

Description

SPECIFICATION Improvements in suction tools This invention relates to suction tools.

Suction tools including a working duct for connection to a source of suction are known. Such tools are used in the electronics industry for the manipulation of delicate components by drawing up the component to one end of the working duct.

However these tools suffer from the disadvantage that additional means must be provided to eject components that adhere or are electrbstatically retained to the end of the working duct.

The present invention seeks to overcome this disadvantage by providing a suction tool which operates from a source of fluid pressure whereby, in use, the source of fluid pressure can be used to effect ejection of the components.

Accordingly this invention provides a suction tool comprising: an inlet duct for connection to a source of fluid pressure, a closable outlet duct, a working duct and a venturi connecting the inlet duct to the outlet duct in the vicinity of a first end of the working duct such that, in use, a reduction or increase in fluid pressure occurs at the second end of the working duct when the outlet duct is correspondingly open or closed.

The outlet duct may conveniently be closed by external means, such as an aperator's thumb, or preferably includes an outlet valve. Conveniently, the venturi comprises a first tubular portion of substantially constant cross-section interjacent a second and third tubular portion having mutually opposed frusto-conical internal surfaces, each of the second and third portions being joined coaxially at its narrower end to the first portion.

The inlet duct may be integral with the venturi thereby comprising a venturi member wherein the inlet duct may be formed by a bore coaxial with the venturi.

A main member housing the outlet duct and the working duct may be provided with a socket for receiving the venturi member such that the venturi will abut one end of the outlet duct. It is necessary that the venturi should communicate with a first end of the working duct and this may be conveniently achieved by forming the venturi member with a substantially cylindrical external surface and by providing an annular groove communicating with the first tubular portion of the venturi by means of at least one fluid transfer port.

An embodiment of the invention will now be described by way of example only and with reference to the accompanying drawing.

The drawing shows a main member 1 of suitable shape for being hand-held and housing an outlet duct 2 and a socket 3 for receiving a venturi member indicated generally by the numeral 4. The main member 1 also houses a working duct 5 which is provided at its end remote from the main member 1 with a nozzle 6 of rubber-like material.

The support member 4 has a substantially cylindrical external surface and encompasses a bore forming an inlet duct 7. Located coaxially with the inlet duct 7 is a venturi comprising two opposed frusto-conical tubular portions 8a and 8b and a substantially cylindrical tubular portion 9 joining the narrow ends of the portions 8a and 8b.

The support member 4 is provided with an annular groove 10 communicating with the cylindrical tubular portion 9 by means of fluid transfer ports 11. The portion 8a abuts one end of the outlet duct 2. The support member 4 is retained in the main member 1 by screws 12.

The main member 1 has a planar surface 13 through which emerges the outlet duct 2. An 'outlet valve 1 4 of conventional platen type is provided consisting of a sealing plate 1 5 having an aperture 1 6 and being held in sliding contact with the surface 1 3 by a bridge member 1 7. The outlet valve 14 is opened by positioning the aperture 1 6 over the outlet duct 2 (as shown in the figure) and progressively closed by sliding the sealing plate 15 in the direction of the arrow. The sealing plate 1 5 has a thumb grip 18 whereby the outlet valve 14 may conveniently be controlled by movement of an operator's thumb.

In use, the inlet duct 7 is connected to a source of pressurised gas (not shown). With the outlet valve 14 open, the gas flows through the inlet duct 7, venturi portions 8a and 8b and outlet duct 2 thereby creating a reduction in gas pressure about the nozzle 6. If the outlet valve 14 is closed, the gas flows into the working duct 5 thereby creating an increase in gas pressure at the nozzle 6.

It will be apparent to those skilled in the art that various other arrangements of this invention are possible. The valve may for example be omitted and the outlet duct closed by means of an operator's thumb being placed over the open end of the outlet duct.

For those applicati'ons in which liquids are likely to be sucked up through the working duct, for example in bio-medical applications, a non-return valve may advantageously be connected in line with the working duct to prevent the ejection of liquid when the outlet valve is closed. In addition, it may be advantageous for the outlet duct to be extended by means of a flexible hose for remote disposal of the working fluid and of any extraneous liquid sucked up by the tool.

A suction tool according to the present invention may alternatively include a venturi member wherein the venturi is integral with the outlet duct instead of the inlet duct.

This invention may also be employed in systems wherein the tool functions as a servo for a device attached to the nozzle and in systems where the working fluid is a liquid.

1. A suction tool comprising an inlet duct connected to a source of pressurised working fluid, a closable outlet duct, a working duct and a venturi connecting the inlet duct to the outlet duct in the vicinity of a first end of the working duct

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Improvements in suction tools This invention relates to suction tools. Suction tools including a working duct for connection to a source of suction are known. Such tools are used in the electronics industry for the manipulation of delicate components by drawing up the component to one end of the working duct. However these tools suffer from the disadvantage that additional means must be provided to eject components that adhere or are electrbstatically retained to the end of the working duct. The present invention seeks to overcome this disadvantage by providing a suction tool which operates from a source of fluid pressure whereby, in use, the source of fluid pressure can be used to effect ejection of the components. Accordingly this invention provides a suction tool comprising: an inlet duct for connection to a source of fluid pressure, a closable outlet duct, a working duct and a venturi connecting the inlet duct to the outlet duct in the vicinity of a first end of the working duct such that, in use, a reduction or increase in fluid pressure occurs at the second end of the working duct when the outlet duct is correspondingly open or closed. The outlet duct may conveniently be closed by external means, such as an aperator's thumb, or preferably includes an outlet valve. Conveniently, the venturi comprises a first tubular portion of substantially constant cross-section interjacent a second and third tubular portion having mutually opposed frusto-conical internal surfaces, each of the second and third portions being joined coaxially at its narrower end to the first portion. The inlet duct may be integral with the venturi thereby comprising a venturi member wherein the inlet duct may be formed by a bore coaxial with the venturi. A main member housing the outlet duct and the working duct may be provided with a socket for receiving the venturi member such that the venturi will abut one end of the outlet duct. It is necessary that the venturi should communicate with a first end of the working duct and this may be conveniently achieved by forming the venturi member with a substantially cylindrical external surface and by providing an annular groove communicating with the first tubular portion of the venturi by means of at least one fluid transfer port. An embodiment of the invention will now be described by way of example only and with reference to the accompanying drawing. The drawing shows a main member 1 of suitable shape for being hand-held and housing an outlet duct 2 and a socket 3 for receiving a venturi member indicated generally by the numeral 4. The main member 1 also houses a working duct 5 which is provided at its end remote from the main member 1 with a nozzle 6 of rubber-like material. The support member 4 has a substantially cylindrical external surface and encompasses a bore forming an inlet duct 7. Located coaxially with the inlet duct 7 is a venturi comprising two opposed frusto-conical tubular portions 8a and 8b and a substantially cylindrical tubular portion 9 joining the narrow ends of the portions 8a and 8b. The support member 4 is provided with an annular groove 10 communicating with the cylindrical tubular portion 9 by means of fluid transfer ports 11. The portion 8a abuts one end of the outlet duct 2. The support member 4 is retained in the main member 1 by screws 12. The main member 1 has a planar surface 13 through which emerges the outlet duct 2. An 'outlet valve 1 4 of conventional platen type is provided consisting of a sealing plate 1 5 having an aperture 1 6 and being held in sliding contact with the surface 1 3 by a bridge member 1 7. The outlet valve 14 is opened by positioning the aperture 1 6 over the outlet duct 2 (as shown in the figure) and progressively closed by sliding the sealing plate 15 in the direction of the arrow. The sealing plate 1 5 has a thumb grip 18 whereby the outlet valve 14 may conveniently be controlled by movement of an operator's thumb. In use, the inlet duct 7 is connected to a source of pressurised gas (not shown). With the outlet valve 14 open, the gas flows through the inlet duct 7, venturi portions 8a and 8b and outlet duct 2 thereby creating a reduction in gas pressure about the nozzle 6. If the outlet valve 14 is closed, the gas flows into the working duct 5 thereby creating an increase in gas pressure at the nozzle 6. It will be apparent to those skilled in the art that various other arrangements of this invention are possible. The valve may for example be omitted and the outlet duct closed by means of an operator's thumb being placed over the open end of the outlet duct. For those applicati'ons in which liquids are likely to be sucked up through the working duct, for example in bio-medical applications, a non-return valve may advantageously be connected in line with the working duct to prevent the ejection of liquid when the outlet valve is closed. In addition, it may be advantageous for the outlet duct to be extended by means of a flexible hose for remote disposal of the working fluid and of any extraneous liquid sucked up by the tool. A suction tool according to the present invention may alternatively include a venturi member wherein the venturi is integral with the outlet duct instead of the inlet duct. This invention may also be employed in systems wherein the tool functions as a servo for a device attached to the nozzle and in systems where the working fluid is a liquid. CLAIMS

1. A suction tool comprising an inlet duct connected to a source of pressurised working fluid, a closable outlet duct, a working duct and a venturi connecting the inlet duct to the outlet duct in the vicinity of a first end of the working duct such that, in use, a reduction or increase in fluid pressure occurs at a second end of the working duct when the outlet duct is correspondingly open or closed.

2. A suction tool as claimed in-claim 1 wherein the closable outlet duct includes an outlet valve for opening and closing the duct.

3. A suction tool as claimed in either of claims 1 or 2, wherein the venturi comprises a first tubular portion of substantially constant crosssection interjacent a second and third tubular portion having opposed frusto-conical internal surfaces and each being joined coaxially at its narrowest end to the first portion.

4. A suction tool as claimed in any of the preceding claims wherein the inlet duct and the venturi are substantially coaxial and together comprise a venturi member.

5. A suction tool as claimed in claim 4 wherein the outlet duct and the working duct are both housed in a main member having an exterior socket communicating with both ducts into which the venturi member can be inserted.

6. A suction tool as claimed in claim 5 wherein the venturi member has a substantially cylindrical external surface, having an annular groove communicating with the first tubular portion of the venturi via at least one fluid transfer port, and disposed so as to communicate with the first end of the working duct when inserted into the socket.

7. A suction tool as claimed in either of claims 5 or 6 wherein the main member has a planar surface through which emerges the outlet duct and wherein the outlet valve comprises a sealing plate held in sliding contact with the planar surface by a bridge member, which plate has an aperture alignable with the outlet duct.

8. A suction tool substantially as hereinbefore described with reference to the accompanying figure.