RU2704328C1 - Device for monitoring and measuring linear dimensions - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: invention can be used in assembly and installation of machine units containing parts with specified axial (end) clearance, in particular for determination of thickness of remote ring of water ring vacuum pumps and compressors. Device comprises a prism-shaped housing with one prismatic recess and two base surfaces, one of which is the prism end face contacting the shaft collars, and second, formed by working faces of prism, contacting with shaft surface for bearing. A through hole is made concentric to the working faces of the prism, in which a hollow post of the indicator is installed on the thread. On the post there is an indicator of a clock type, and the measuring rod of the indicator is in the through hole of the prism and when measuring it contacts the end surface of the hole for bearing of the bearing housing. Prism spring is secured at prism back side.

EFFECT: expansion of technological capabilities due to use of the device for various standard sizes of pumps, direct determination of thickness of a remote ring, reduction of time of control and increase of accuracy of measurements.

3 cl, 2 dwg

Description

The invention relates to measuring equipment and is intended to control linear dimensions in conditions of limited access.

The device can be used in various fields of technology when assembling and installing machine components containing parts with a given axial (end) clearance.

In particular, the device is relevant in the manufacture and repair of liquid ring vacuum pumps and compressors type BBH and VK. The most critical moment of assembly is the establishment of a given uniform clearance between the end surfaces of the wheel and the foreheads. (Water ring vacuum pumps and compressors. Technical description. Instruction manual). These gaps, which determine the losses in the machine from the flow of air from the discharge side to the suction side, are established by means of gaskets between the body and the sides, are controlled by a probe and must be within 0.1-0.5 mm for various pump sizes.

However, when the impeller is displaced on the shaft, fixing the shaft in the axial direction by the bearing assembly can lead to one-sided displacement of the wheel, i.e. to the unevenness of the gaps between the ends of the wheel and the foreheads.

To eliminate such cases, axial adjustment of the bearing assembly of the free shaft end is provided by means of a distance ring mounted under the outer ring of the bearing.

The determination of the thickness of the distance ring is carried out in the following sequence:

After assembling the pump and setting the end clearances "S" between the ends of the wheel and the front sides with bearings not installed, the shaft is fed towards the free end of the shaft until the end of the impeller contacts the front end. Depth "E" is measured (see Fig. 2) of the bearing housing bore under the bearing, the distance "F" is measured from the end surface of the bearing housing to the shoulders on the shaft, against which the bearing inner ring abuts. From the difference of the measured values “E” and “F”, the value of the end gap “S” set during assembly is subtracted, and thus, the thickness “C” of the distance ring is determined, which ensures the same gap between the ends of the wheel and the foreheads.

C = (E-F) -S = T-S

A well-known depth gauge according to GOST 162-90, comprising a housing with one base surface, a frame with a vernier and a movable rod with a scale that moves when measuring the depth of the hole relative to the frame. The value of the depth of the hole is read in nonius after the rod touches the end of the hole. When measuring, the probability of the rod falling onto the curved portion of the fillet is not excluded, especially when measuring the distance from the end of the bearing housing to the shaft shoulders, which will lead to measurement errors. After measuring the values of "E" and "F", the thickness of the distance ring "C" is determined by calculation, as described above; which also introduces errors and increases control time.

Known indicator depth gauge according to GOST 7661-67, containing a stationary case with one base surface, a dial gauge with a movable measuring rod in contact with the measured surface in contact and mounted in a holder (stand) mounted on the case. Strictly speaking, the indicator depth gauge is not a measuring, but a calibration tool. Therefore, when monitoring the depth of the hole, the indicator depth gauge is set to zero counting according to installation patterns or end measures. When determining the depth of the hole, the indicator head is added or taken to the installation length.

After measuring “E” and “F”, the thickness of the distance ring “C”, as in the first case, is determined by calculation.

Also known is a device (description of the invention to patent RU 2418263, G01B 5/24, publ. 05/10/2011), designed to control the axial clearance in the assembly units (prototype). The device comprises a housing with base surfaces, an indicator mounted on a housing on a stand, a lever pivotally mounted on an axis, having the ability to adjust the position of the axis relative to the base surface and interacting on one side with a part whose position is to be controlled and, on the other, with an indicator, slider and a pen. However, this device is being developed for specific brands of machines, since its base surfaces must correspond to these machines, and calibration requires the development of special devices. The device allows you to control the magnitude of the axial clearance (axial displacement) with the installed adjusting gasket. If the axial clearance deviates from the nominal value, you need to select another adjustment gasket and re-measure, i.e. the device does not allow for a single measurement to determine the thickness of the shim.

The objective of the proposed technical solution is to expand technological capabilities, directly determine the thickness of the adjusting distance ring, reduce the monitoring time and increase the accuracy of measurements.

The problem is solved in that the housing of the device for monitoring and measuring linear dimensions is made in the form of a prism with one prismatic recess and two base surfaces, one of which is the end face of the prism in contact with the shoulders of the shaft, and the second - formed by the working faces of the prism in contact with the surface shaft under the bearing, through hole is concentric to the working faces of the prism, in which a hollow indicator stand is installed on the thread. A watch-type indicator is fixed on the rack, a measuring rod with an extension is located in the through hole of the prism and, when measuring, is in contact with the end surface of the opening of the bearing housing. To ensure complete fit of the end surface of the prism to the shoulders of the shaft, symmetrical chamfers are made on the edges of intersection of the end surface and the working faces of the prism, the legs of which must be not less than the radius of the mounting chamfer of the inner ring of the bearing. To hold the prism against the shaft during measurements, a spacer spring is installed on the back of the prism in contact with the bore surface of the bearing housing.

The invention is illustrated by drawings (see. Fig. 1, 2) on the example of determining the thickness of the adjusting distance ring of the vacuum liquid ring pumps type BBH.

FIG. 1 - device, general view. FIG. 2 - use of the device.

A device for monitoring and measuring linear dimensions (Fig. 1) contains a housing 1 made in the form of a prism with one prismatic recess, base surfaces, one of which is the end face of the prism in contact with the shoulders of the shaft, and the second is formed by the working faces of the prism in contact with shaft surface under the bearing. In prism 1, a through hole 2 is made concentrically to the working faces of the prism, in which a hollow column 4 of indicator 5 is mounted and fixed with a nut 3 and fastened to the column 4 by a screw 6. The measuring rod 7 of indicator 5 is located in the axial channel of the column 4 and the through hole 2 prism 1 and when measuring is in contact with the end surface of the hole for the bearing of the bearing housing. On the back surface of the prism 1 is fixed spacer spring 8, mainly of the leaf type. At the edges of intersection of the end surface with the working faces of the prism, symmetrical chamfers 9 are made, legs “a” of which must be not less than the radius of the mounting chamfer of the inner ring of the bearing.

The device setup sequence and measurement order.

Install indicator 5 in the rack 4 so that the head of the rod 7 of indicator 5 protrudes above the end surface of the prism 1 and screw 6 fix the indicator 5 in the rack 4. To set the “zero”, the prism 1 with the end surface (in contact with the shaft shoulder) is installed on a clean smooth metal surface. In this case, the measuring rod 7 is mixed upward and mounted in the same plane with the end surface of the prism 1. Turn the bezel of the indicator 5, combine the “zero” bar of the scale with the arrow. Without removing the device from the surface, turning the indicator bezel 5 counterclockwise, set the end gap “S” specified during assembly between the ends of the impeller and the front sides, which means: when measuring the distance between the shaft shoulder and the end surface of the bearing housing hole, the value will be subtracted from this distance specified end clearance "S".

The device is ready for measurements.

Wipe the end surface of the bore of the bearing housing at the measurement site and the seat on the shaft under the bearing with a clean soft cloth.

Prism 1 is mounted on the shaft (Fig. 2) and is moved forward to the end face of the prism 1 against the shaft shoulder. The spacer spring 8, interacting with the wall of the housing opening, tightly presses the prism 1 to the shaft surface, eliminating distortions during installation. The measuring rod 7 with the tip is in contact with the end surface of the bore of the bearing housing and, when the prism moves along the shaft, activates the recording mechanism of the indicator 5. Chamfers 9 of the prism 1 overlap the radius r of the fillet of the shaft shoulder, which allows the prism end to fit snugly against the shaft shoulder. When the end face of the prism rests on the shaft shoulder, indicator 5 will show the desired value - the thickness of the distance ring “C”.

The dial indicator is used not only as a measuring tool, but also as a decisive device.

C = T-S

The proposed device allows you to directly determine the thickness of the remote ring, eliminate mathematical calculations, reduce the monitoring time and increase the accuracy of measurements, expand technological capabilities through the use of the device for various pump sizes.

Claims (3)

 1. A device for monitoring and measuring linear dimensions, comprising a housing with base surfaces, a rack with an indicator mounted on the housing, a measuring rod which interacts with the surface of the part to be controlled, characterized in that the housing is made in the form of a prism with a one-side notch and two base surfaces , one of which is the end face of the prism in contact with the shoulders of the shaft, and the second, formed by the working faces of the prism in contact with the surface of the shaft under the bearing, concentrically working they have a through hole in the faces of the prism, in which a hollow stand with an indicator fixed to it is mounted on the thread, the measuring rod of the indicator is located in the cavity of the stand and the through hole of the prism, and the rim of the indicator head is turned clockwise from the “zero” setting of the device by the amount specified axial clearance. 2. The device according to p. 1, characterized in that on the ribs of the intersection of the end surface of the prism in contact with the shoulders of the shaft, symmetrical chamfers are made with the working faces of the prism, the legs of which should be at least the radius of the mounting chamfer of the inner ring of the bearing. 3. The device according to p. 1, characterized in that on the rear side of the prism fixed spacer spring predominantly leaf type.

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