GB2056022A

GB2056022A - Pressure Regulator

Info

Publication number: GB2056022A
Application number: GB7926800A
Authority: GB
Original assignee: BOC Ltd
Current assignee: BOC Ltd
Priority date: 1979-08-01
Filing date: 1979-08-01
Publication date: 1981-03-11

Abstract

A pressure regulator for attachment to a pressure cylinder or pipeline includes a pressure adjusting assembly comprising a pressure setting screw 5, a knob 6 and a generally cylindrical keying member 7 for transmitting rotary movement of the knob 6 to the pressure setting screw 5. The keying member 7 includes tongues and grooves 25 which cooperate with tongues and grooves 20 in a counterbore of the knob 6 and a through hole 26 which receives a tongue 12 on the pressure setting screw 5. <IMAGE>

Description

SPECIFICATION Improvements In Pressure Regulators The present invention relates to pressure regulators for attachment to cylinders and pipelines containing fluid under pressure and more particularly, to pressure adjusting assemblies which form part of such pressure regulators.

It is known for a pressure adjusting assembly forming part of a pressure regulator to include a pressure setting screw and a knob threadable onto the pressure setting screw. Rotary movement of the knob is normally transmitted to the pressure setting screw by means of grub screws.

A disadvantage of the known pressure adjusting assembly is that the grub screws are difficult to manipulate and from time to time, fail to impart rotary movement of the knob to the pressure setting screw.

According to the present invention, a pressure regulator for attachment to a cylinder or pipeline containing fluid under pressure includes a pressure adjusting assembly which comprises a pressure setting screw threadable into a body part of the regulator for setting the maximum pressure at which the fluid can flow from the cylinder through the regulator, a knob threadable onto the pressure setting screw and a keying member having means for positively engaging complementary means on the pressure setting screw and the cap respectively for transmitting rotary movement of the cap to the pressure setting screw.

Preferably, the keying member is received in a counterbore of the knob, tongues and grooves on the outer periphery of the keying member cooperating with tongues and grooves formed on the surface of the counter-bore to prevent independent rotary movement of the cap relative to the keying member, the counterbore communicating with a threaded hole in the cap which receives the pressure setting screw, and a tongue at one end of the pressure setting screw entering through a hole formed in the keying member to prevent independent rotary movement of the keying member relative to the pressure setting screw.

An embodiment of the invention will now be described, by way of example, reference being made to the Figures of the accompanying diagrammatic drawings in which: Figure 1 is a perspective view of a pressure regulator for attachment to a cylinder containing fluid under pressure; Figure 2 is an exploded perspective view of a pressure adjusting assembly forming part of the pressure regulator of Figure 1; and Figure 3 is a view in longitudinal cross-section of a knob forming part of the pressure adjusting assembly of Figure 2.

As shown in Figure 1, a pressure regulator 1 for attachment to a cylinder (not shown) containing fluid under pressure, for example acetylene, includes a body part 2, pressure gauges 3 and a pressure adjusting assembly 4.

Referring also to Figures 2 and 3, the pressure adjusting assembly 4 comprises a pressure setting screw 5, a knob 6 and a keying member 7.

The pressure setting screw 5 is threaded along substantially its whole length and at a first, or inner end 9, has a counterbore (not shown) which retains a rotatable ball 10. At the opposite end 11 of the pressure setting screw diametrically opposed segments of the screw are removed leaving a tongue 1 2.

The knob 6 has a central boss 1 3 having at one end 1 6 a hole with internal threads 1 7 which hole communicates with a counterbore 1 8 formed around its periphery with a plurality of axially extending tongues and grooves 20. The knob 6 has a skirt 14 formed on its outer surface with flutes 1 5. Extending radially outwardly from the boss 13 to the skirt 14 are a plurality of equispaced ribs 21.

The internal threads 17 are dimensioned to receive the threads on the pressure setting screw 5.

The keying member 7 is generally cylindrical in cross-section and has a plurality of axially extending tongues and grooves 25 formed around its circumference which are dimensioned and located to fit with the tongues and grooves 20 in the counterbore 1 8. A central hole 26 extends axially through the keying member 7 and is dimensioned to receive the tongue 1 2 of the pressure setting screw 5.

In use, with the pressure regulator 1 attached to a cylinder containing a gas such as acetylene under pressure, the pressure setting screw 5 is threaded into a hole on a surface 30 of the body part 2 of the regulator until the ball 10 engages a spring diaphragm system which operates a valve and gas is permitted to flow from the cylinder and through the regulator 1. The pressure setting screw 5 is threaded into the body part 2 until the maximum permitted pressure is reached on the gauges 3.

Next, the knob 6 is screwed down on top of the pressure setting screw 5 until the end 1 6 engages the surface 30 on the body part 2 at which time the tongue 1 2 of the pressure setting screw will protrude through the threaded hole into the counterbore 1 8. Finally, the keying member 7 is inserted into the counterbore 1 8 so that the tongue 12 extends into the hole 26.

It will be evident that when the knob 6 is rotated with a view to reducing the pressure of the gas passing through the regulator 1 then the rotary movement of the knob 6 will be transmitted via the keying member 7 to the pressure setting screw 5. There is no danger that the maximum pressure setting originally set by means of the pressure setting screw 5 can be exceeded since the end 1 6 of the knob 6 will encounter the surface 30 of the body part 2.

An advantage of the embodiment described above is that the keying member 7 is readily positioned within the counterbore 1 8 so that the tongue 12 can be accommodated by the hole 26.

Once the keying member 7 is in position in the counterbore 18, then a cover 32 can be placed in a shallow indentation at the end of the cap to prevent accidental or unofficial removal of the keying member 7.

Claims

1. A pressure regulator for attachment to a cylinder or pipeline containing fluid under pressure, the pressure regulator including a pressure adjusting assembly comprising a pressure setting screw threadable into a body part of the regulator for setting the maximum pressure at which the fluid can flow from the cylinder through the regulator, a knob threadable onto the pressure setting screw and a keying member having means for positively engaging complementary means on the pressure setting screw and the knob respectively for transmitting rotary movement of the knob to the pressure setting screw.

2. A pressure regulator as claimed in claim 1, in which the keying member is received in a counterbore of the cap, tongues and grooves on the outer periphery of the keying member cooperating with tongues and grooves formed on the surface of the counterbore to prevent independent rotary movement of the cap relative to the keying member, the counterbore communicating with a threaded hole in the knob which receives the pressure setting screw, and a tongue at one end of the pressure setting screw entering through a hole formed in the keying member to prevent independent rotary movement of the keying member relative to the pressure setting screw.

3. A pressure regulator for attachment to a cylinder or pipeline containing fluid under pressure constructed and arranged substantially as hereinbefore described with reference to and as illustrated in the Figures of the accompanying drawings.