FI88206C - Volume flow meter for streaming medium - Google Patents

Description

1 88206

Volume flow meter for the flowing medium

The invention relates to a volumetric flow meter for a flowing medium, the meter having a substantially straight measuring channel 5 narrower in length, having the same cross-sectional shape and area along its entire length, an outlet channel connected to the measuring channel for most of its length, or a corresponding flow barrier having a cross-sectional shape and area corresponding to the cross-sectional shape and area of the measuring channel, a flow positioning valve located on the inlet or outlet of the meter, the position of the float indicating the value of the fluid flow through the meter.

DE 3906085 A1, GB 2189648 A and US Pat. U.S. Pat. No. 4,459,859 describes typical flowmeters operating on such a principle, but they do not have the possibility of setting the measuring range.

In previous implementations, it has been possible to set the flow-measuring range of the flowmeter only by setting the float counterforce, weight, flow resistance or spring load: '25 or by setting the flow opening between the measuring tube and the float, making it difficult to control a wide operating range with the same meter.

There are implementations in which the measuring range can be adjusted with a cone set inside the float in the measuring tube, but it does not achieve a very wide range of measuring ranges.

‘The volume flow meter according to the present invention is characterized in that the flow measuring range of the meter can be defined in relation to its length by adjusting the width of the flow gap between the narrow measuring channel 35 and the outlet channel by means of a setting piece.

The meter according to the invention also achieves good linearity simply by making a flow gap of the same width over the entire distance of the measuring tube or it can be easily modified by changing the shape of the gap.

With the meter according to the invention, good viscosity independence is achieved because the flow-forming gap has a clear one-time resistance due to the sharp angles of the gap.

In the following, the invention will be explained in more detail by means of an embodiment of the invention with reference to the accompanying drawing, in which Fig. 1 shows a longitudinal section of a volume flow meter according to the invention, and Fig. 2 a section A-A of Fig. 1.

The volume flow meter shown in the drawing has a float 4 placed directly in a measuring channel 1 of circular cross-section, on the side of which a curved recess 8 is made for the space required by the setting piece 5 of the flow gap 2. Otherwise, the cross-section of the float corresponds to the cross-section of the measuring channel. The outlet channel 3 is also circular in cross-section and is located parallel to the measuring channel so that the circles of the cross-sections of the measuring channel and the outlet channel partially overlap. Inside the outlet channel there is a positioning piece 5 with a slot 2 in the form of a tube 25 of circular cross-section along its entire length, which can be rotated about its longitudinal axis during positioning. The cross section of the layout corresponds to the cross section of the removal channel.

A flow setting valve 6 for adjusting the flow of the flowing medium 30 is located on the outlet side of the meter. Its position and at the same time the amount of medium flowing through the meter is adjusted by rotating it around the axis of rotation 9.

As the medium flows through the meter from the measuring channel 1 35 below the float 4 through the gap 2 of the setting piece 5 to the outlet channel 3, it causes a pressure difference in the flow gap 2 over the float 4, which together with the counterforce 4 88206 determines the flow rate. The amount of flow can be read by monitoring the position of the float on a scale through the wall of the transparent housing. When the flow gap 5 of the meter is narrow, the movement of the float can be made large even with a small flow value of the medium, correspondingly, when the flow gap is enlarged, larger flow rates can be measured with the same meter. In this way, the amount of flow can be read from the height position of the float when the width of the set flow gap is known. Thus, with the same product, 10 different measuring ranges can be achieved over a wide range by adjusting the width of the flow gap.

The advantage of the product is the advantageous manufacturability, when a very wide need for measuring equipment can be realized with the same components. The manufacturing accuracy of the product components does not affect the accuracy of the product, as the finished product can be calibrated under laboratory conditions after completion to display correctly with high accuracy.

The drawing and the related explanation are only intended to illustrate the invention. The details of the meter according to the invention can be modified within the scope of the appended claims.

The flow gap setting piece 5 can be located other than in the outlet channel 3 and can be other than tubular. For example, a gap 2 '"' 25 on the side of the gap may be used to partially cover the protruding lip-like strip. If the strip is wedge-shaped so as to widen towards its other end, the displacement of the strip in the axial direction adjusts the gap.

The measuring and discharge channels 1, 3 can also have the shape of ____30. Instead of the steplessly adjustable cylindrical setting piece 5, it is possible to use, for example, an outlet pipe with a polygonal cross-section and a setting piece, whereby the position of the setting piece can be changed step by step.

• '35 Any known valve design can be used as the control valve 6.

Claims (8)

A volumetric flow meter for a flowing medium, the meter having a substantially straight measuring channel (1) narrower than its length, having the same cross-sectional shape and surface area along its entire length, - an outlet channel connected to the measuring channel for most of its length (2) 3), 10. a float (4) placed in the measuring channel or a similar flow barrier with a cross-sectional shape and area corresponding to the cross-sectional shape and area of the measuring channel, - a flow setting valve (6) located on the inlet or outlet of the meter, 4) the position indicates the value of the flow of fluid flowing through the meter, characterized in that the measuring range of the meter flow can be determined by adjusting the width of the flow gap (2) between the narrow measuring channel (1) and the outlet channel (3) by means of a setting piece (5). Volume flow meter according to Claim 1, characterized in that it has a tubular flow gap width setting piece (5) arranged in the outlet channel (3), which has a longitudinal slot (2) and whose position with respect to its longitudinal axis can be changed. Volume flow meter according to Claim 2, characterized in that the outlet duct (3) and the setting piece (5) are both circular in cross section. Volume flow meter according to Claim 3, characterized in that the side of the float (4) has a concave longitudinal recess (8) against which the side of the setting piece (5) can be fitted. 4 S 8 2 C o Volume-flow meter according to one of Claims 1 to 4, characterized in that the linearity of the scale of the flow meter can be influenced by changing the shape of the flow gap (2). 5 8820ό Volumetric flow meter according to one of Claims 1 to 5, characterized in that the counterforce of the float (4) can be a spring, pressure or other counter force in addition to the traction caused by the ground. Volume flow meter according to one of Claims 1 to 6, characterized in that the float (4) is replaced by a spring-loaded plate. Volume flow meter according to one of Claims 1 to 7, characterized in that the flow gap (2) can be divided into several parts in order to achieve better strength. 6 88206