GB1560156A

GB1560156A - Apparatus for dispensing mortar

Info

Publication number: GB1560156A
Application number: GB20248/77A
Authority: GB
Original assignee: Charlesworth M J
Current assignee: Charlesworth M J
Priority date: 1978-04-24
Filing date: 1978-04-24
Publication date: 1980-01-30

Description

(54) APPARATUS FOR DISPENSING MORTAR (71) I, MICHAEL JOHN CHARLES WORTH, a British subject, of 2 Chalfont Road, Oxford OX2 6TH, do hereby declare the invention, for which I pray that a patent may be granted to me and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to apparatus for dispensing mortar particularly for use in the re-pointing of brickwork and in the laying of brickwork, but also for the laying of floor screeds and for rendering.

The repointing of brickwork is generally carried out manually and is an extremely labour-intensive operation. Most of the labour is necessary for the operation of placing the mortar in the joints of the brickwork rather than in the mixing of the mortar and the raking of old mortar out of the joints before re-pointing can take place.

To reduce the labour required, various forms of pumping apparatus have been used for supplying the mortar to a nozzle from which it is discharged in the joints.

One form of apparatus for this purpose is disclosed in British Specification No.

744,021, but this is quite complex and calls for a supply of compressed air to force the mortar from a pressure vessel to the nozzle.

Somewhat similar considerations apply to the laying of brickwork where a layer of mortar has to be applied to the top of a previously laid course of bricks.

The aim of the present invention is to provide an improved apparatus for dispensing mortar, particularly in the re-pointing or laying of brickwork, with which the rate of supply of the mortar can be closely controlled.

According to this invention, apparatus for this purpose comprises a power-operated variable-speed peristaltic pump including a flexible pump tube, a hopper or other container for the mortar mounted above the pump tube and with an outlet connected to an inlet end of the pump tube, a device for vibrating the hopper or other container to cause mortar in the hopper or other container to flow through the outlet, and a mortar dispensing nozzle, which has a handle to enable it to be held and directed by an operator and which has a hose connecting the nozzle to an outlet end of the pump tube.

I have found that by using a peristaltic pump in such apparatus, the dispensing of the mortar can be effected at a very satisfactory and steady rate and, with a suitably shaped nozzle, brickwork can be re-pointed very much more rapidly than is possible with the usual entirely manual operation. What is more, a much lower degree of skill is required.

The variable-speed drive of the pump enables the rate at which the mortar is dispensed to be controlled and varied as necessary in dependence on the height of the joints which are to be re-pointed and the depth to which the joints are to be refilled with mortar.

Somewhat similarly, when laying brickwork, a bed of mortar can be dispensed using the apparatus in accordance with the invention very much more quickly than the bed can be formed manually using a trowel. Less skill is required to form a bed of uniform thickness and again therefore less skilled and therefore somewhat less expensive labour can be used. For laying brickwork, a greater mortar output is required than for repointing brickwork and this may be achieved by increasing the speed of the pump and optionally also by exchanging the flexible pump tube of the pump for a tube of greater diameter. Most peristaltic pumps are adjustable to enable them to operate with tubes of different diameters.

Generally speaking about 70 percent of the total labour involved in re-pointing brickwork, when this is done entirely manually, is necessary for applying the new mortar into the joints and Î have found that the labour for this purpose can be reduced by at least 50 percent by the use of the apparatus in accordance with the invention.

Different speeds of movement of the nozzle will be achieved by different operators and by the same operator in dependence upon circumstances, particularly when repointing brickwork. For this reason it is essential for the pump to have a variablespeed drive as has already been mentioned.

Peristaltic pumps are self-priming, but particularly for re-pointing brickwork, comparatively stiff mortar is necessary and this will not flow of its own accord. It is for this reason that it is necessary to provide the hopper or other container above the flexible pump tube and also to vibrate the hopper or other container to cause the mortar to flow through the outlet to the tube.

Re-pointing of brickwork generally takes place on inhabited buildings which therefore generally have an electric power supply. The pump is therefore preferably driven by an electric motor and this may be of the variable-speed variety, but since the motor generally needs to operate through a speedreduction gear, preferably an infinitely variable speed gear is provided between the motor and the pump.

Alternatively, on building sites where an electrical supply is not available, the pump may be driven by an air motor supplied by a compressor, or it may be driven by a small internal combustion engine both of which preferably operate, as with the electric motor, through an infinitely variable speed gear.

To control the output from the nozzle, the nozzle is preferably provided with a trigger or other control member which controls a switch in the circuit of the motor, when the pump is electrically driven, to start and stop the pump. Immediately the motor of the pump is stopped, flow from the pump ceases and in this way starting and stopping of the flow of mortar from the nozzle as is necessary can very easily be achieved by the operator.

To achieve full control of the rate at which the mortar is dispensed without pausing in re-pointing of brickwork, the nozzle may also be provided with a speed control member for adjusting the speed of the motor. However, this involves rather more complicated circuitry and is not therefore commonly necessary.

Preferably, when the pump is driven by an electric motor, the motor is reversible and this enables the pump to be reversed to pump mortar from the nozzle and from the connecting hose back into the hopper or other container at the end of an operation. In the absence of this facility, cleaning out of the nozzle, hose and flexible pump tube before the mortar hardens is a rather timeconsuming operation.

If an interval in the use of the apparatus becomes necessary when the whole apparatus is charged with mortar, the nozzle is preferably directed back into the hopper and the pump is left in operation so that the mortar is circulated by the pump from the hopper to the nozzle and back into the hopper to keep the mortar in a pumpable condition and prevent premature setting.

An example of apparatus in accordance with the invention and of its use is illustrated in the accompanying somewhat diagrammatic drawings, in which: Figure 1 is a perspective view of the apparatus with parts broken away to show internal details; and, Figure 2 is a perspective view to a much smaller scale showing the apparatus in use in the re-pointing of brickwork.

As shown in Figure 1, the apparatus comprises a box-like frame 1 of steel sections which are welded to each other at the corners of the frame. Some of these sections are shown broken away. The frame 1 includes a bottom bearer member 2 and supports at its top a rectangular mortar hopper 3, which has a bottom plate 4. The bottom plate 4 slopes downwards to one corner at which there is an outlet opening 5. The box frame 1 is enclosed at its sides by detachable cover plates, which are not shown, to form a housing.

A variable-speed electric motor 6 has a base plate 7 which is bolted to the bearer 2 and an output shaft of the motor 6 drives a peristaltic pump, which is generally indicated at 8. The peristaltic pump 8 comprises a flexible pumping tube 9 which is made of neoprene and is held in position by clamps 10 and 11 on a part-circular bed 12. The bed 12 is supported on a base plate 13 which is bolted to the bearer 2. An inlet end of the pumping tube 9 is connected by a coupling 14 to an upright pipe 15 which in turn is connected by a further coupling 16 to the outlet 5.

The outlet end of the pumping tube 9 is continuous with a hose 17 which leads to a mortar dispensing gun 18.

The peristaltic pump 8 comprises a rotor 19 which is fixed on the end of an output shaft 20 of the motor 6 and carries three cantilevered rollers 21.

The rotor 19 is normally rotated by the motor 6 in the direction an arrow 22 and this causes the rollers 21 to move in succession into contact with the pumping tube 9 and to squeeze the tube flat as they move along the part of the tube supported on the bed 12 as is conventional in peristaltic pumps.

The shaft 20 is additionally supported by a journal bearing in a pedestal 23 which is supported by a base plate 24 which is bolted to the bearer 2 in between the base plates 7 and 13 of the motor 6 and the pump 8 respectively.

As has already been mentioned, in this example the electric motor 6 is of the variable-speed type and it is controlled by controls in a control box 25. These controls consist of an on-off switch, a forward and reverse control and a speed control. The controls in the control box 25 are connected-to the motor 6 through a cable 26.

The motor 6 can also be controlled by a trigger 27 which is mounted on a handle 28 of the gun 18 and which also forms an on-off switch for the motor. The gun 18 also carries a control knob 29 which is rotatable between an off position, a forward position in which the motor 6 rotates the rotor 19 in the direction of the arrow 22 and a reverse position in which the motor 6 rotates the rotor 19 in a direction counter to the arrow 22. The switch of the trigger 27 and the control controlled by the control knob 29 are connected to the motor 6 by a cable 36 which extends along and is clipped at intervals to the hose 17. The control knob 29 may also vary the speed of the motor 6 in dependence upon the distance through which the knob 29 is turned from the off position towards either the forward or the reverse position.

The gun 18 has a barrel 31 through which a stainless steel tube 32, which forms the nozzle, extends. The forward end of the tube 32 is of a somewhat smaller diameter than the rear end, there being a tapering step in the tube near the forward end of the barrel 31.

The rear end of the tube 32 is connected by a coupling 33 to the hose 17.

An exchangeable nozzle outlet 34 is fitted over the front end of the tube 32 and is preferably screwed into position. The nozzle outlet 34 shown in the drawings has a fish-tail ending 35 which is suitable for discharging mortar for re-pointing brickwork, but nozzle outlets of various other shapes may be used such as a nozzle with a wider and thicker fish-tail for depositing mortar in laying new brickwork. Alternatively for re-pointing brickwork, a nozzle outlet of rectangular cross-section with a width somewhat less than its height may be used. This nozzle outlet may be provided with a projecting nib immediately above it for guiding the nozzle along the joint being re-pointed.The nib is in the form of a thin plate or tab which is inserted into the top of the joint and the face of the nozzle outlet surrounding its orifice is held in contact with the brickwork as the nozzle is moved along the joint in order to prevent mortar from escaping from the joint onto the face of the brickwork. In another modification of the nozzle outlet, there is a projecting stop below the orifice and the side walls of the nozzle at the sides of the orifice slope so that as the nozzle outlet is moved along the joint, the joint is filled with mortar and the nozzle outlet shapes this mortar at a slight outward and downward slope to provide a weatherstruck shape.

In place of the variable-speed electric motor 6, the pump may be driven by an air motor or by a small internal combustion engine. In either of these cases, or if a constant speed electric motor is used, the rotor 19 is not fixed directly on the end of the motor output shaft 20, but instead the journal bearing and the pedestal 23 are substituted by an infinitely variable speed gear with the rotor 19 mounted on an output shaft of the gear.

To ensure that mortar placed in the hopper 3 flows to the outlet 5 and thence to the pump 8, the bottom plate of the hopper 3 is fitted with a vibrating device 36 which is indicated very diagrammatically in Figure 1 of the drawings. This device comprises a small electric motor driving an out-of-balance rotor at high speed as is common in concrete vibrators.

In operation, to re-point brickwork as shown in Figure 2, an operator of the apparatus mixes mortar and places it in the hopper 3. He then sets the speed control of the motor 6 by means of the control box 25 to an appropriate speed according to his skill and the nature of the joints to be re-pointed and the motor 6 is switched on by closing a main switch in the control box 25. The motor does not however at this stage start operating because its circuit is broken by the switch controlled by the trigger 27 and also by the control knob 29 which at this stage is in an "off" position. The operator then takes up the gun 18 fitted with an appropriate nozzle outlet and holds the outlet at the beginning of the first joint to be re-pointed. He then turns the control knob 29 to a forward position and presses the trigger 27.Pressing of the trigger 27 sets the motor 6 and the pump 8 in operation and mortar is pumped to the nozzle outlet 34 and into the joint. The operator moves the nozzle outlet 34 steadily along the joint stopping and starting the motor 6 as necessary by releasing and pressing the trigger 27 to supply mortar as required, he also varies the speed of movement of the nozzle outlet 34 along the joint so that the joint is uniformly filled with mortar.

As shown in Figure 2, for ease of mobility, the box frame 1 is fitted with a pair of wheels 37 and a handle 38.

WHAT I CLAIM IS: 1. Apparatus for dispensing mortar comprising a power-operated variable-speed peristaltic pump including a flexible pump tube, a hopper or other container for the mortar mounted above the pump tube and with an outlet connected to an inlet end of the pump tube, a device for vibrating the hopper or other container to cause mortar in the hopper or other container to flow through the outlet, and a mortar dispensing nozzle which has a handle to enable it to be held and directed by an operator and which

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

Claims

**WARNING** start of CLMS field may overlap end of DESC **. example the electric motor 6 is of the variable-speed type and it is controlled by controls in a control box 25. These controls consist of an on-off switch, a forward and reverse control and a speed control. The controls in the control box 25 are connected-to the motor 6 through a cable 26. The motor 6 can also be controlled by a trigger 27 which is mounted on a handle 28 of the gun 18 and which also forms an on-off switch for the motor. The gun 18 also carries a control knob 29 which is rotatable between an off position, a forward position in which the motor 6 rotates the rotor 19 in the direction of the arrow 22 and a reverse position in which the motor 6 rotates the rotor 19 in a direction counter to the arrow 22. The switch of the trigger 27 and the control controlled by the control knob 29 are connected to the motor 6 by a cable 36 which extends along and is clipped at intervals to the hose 17. The control knob 29 may also vary the speed of the motor 6 in dependence upon the distance through which the knob 29 is turned from the off position towards either the forward or the reverse position. The gun 18 has a barrel 31 through which a stainless steel tube 32, which forms the nozzle, extends. The forward end of the tube 32 is of a somewhat smaller diameter than the rear end, there being a tapering step in the tube near the forward end of the barrel 31. The rear end of the tube 32 is connected by a coupling 33 to the hose 17. An exchangeable nozzle outlet 34 is fitted over the front end of the tube 32 and is preferably screwed into position. The nozzle outlet 34 shown in the drawings has a fish-tail ending 35 which is suitable for discharging mortar for re-pointing brickwork, but nozzle outlets of various other shapes may be used such as a nozzle with a wider and thicker fish-tail for depositing mortar in laying new brickwork. Alternatively for re-pointing brickwork, a nozzle outlet of rectangular cross-section with a width somewhat less than its height may be used. This nozzle outlet may be provided with a projecting nib immediately above it for guiding the nozzle along the joint being re-pointed.The nib is in the form of a thin plate or tab which is inserted into the top of the joint and the face of the nozzle outlet surrounding its orifice is held in contact with the brickwork as the nozzle is moved along the joint in order to prevent mortar from escaping from the joint onto the face of the brickwork. In another modification of the nozzle outlet, there is a projecting stop below the orifice and the side walls of the nozzle at the sides of the orifice slope so that as the nozzle outlet is moved along the joint, the joint is filled with mortar and the nozzle outlet shapes this mortar at a slight outward and downward slope to provide a weatherstruck shape. In place of the variable-speed electric motor 6, the pump may be driven by an air motor or by a small internal combustion engine. In either of these cases, or if a constant speed electric motor is used, the rotor 19 is not fixed directly on the end of the motor output shaft 20, but instead the journal bearing and the pedestal 23 are substituted by an infinitely variable speed gear with the rotor 19 mounted on an output shaft of the gear. To ensure that mortar placed in the hopper 3 flows to the outlet 5 and thence to the pump 8, the bottom plate of the hopper 3 is fitted with a vibrating device 36 which is indicated very diagrammatically in Figure 1 of the drawings. This device comprises a small electric motor driving an out-of-balance rotor at high speed as is common in concrete vibrators. In operation, to re-point brickwork as shown in Figure 2, an operator of the apparatus mixes mortar and places it in the hopper 3. He then sets the speed control of the motor 6 by means of the control box 25 to an appropriate speed according to his skill and the nature of the joints to be re-pointed and the motor 6 is switched on by closing a main switch in the control box 25. The motor does not however at this stage start operating because its circuit is broken by the switch controlled by the trigger 27 and also by the control knob 29 which at this stage is in an "off" position. The operator then takes up the gun 18 fitted with an appropriate nozzle outlet and holds the outlet at the beginning of the first joint to be re-pointed. He then turns the control knob 29 to a forward position and presses the trigger 27.Pressing of the trigger 27 sets the motor 6 and the pump 8 in operation and mortar is pumped to the nozzle outlet 34 and into the joint. The operator moves the nozzle outlet 34 steadily along the joint stopping and starting the motor 6 as necessary by releasing and pressing the trigger 27 to supply mortar as required, he also varies the speed of movement of the nozzle outlet 34 along the joint so that the joint is uniformly filled with mortar. As shown in Figure 2, for ease of mobility, the box frame 1 is fitted with a pair of wheels 37 and a handle 38. WHAT I CLAIM IS:

1. Apparatus for dispensing mortar comprising a power-operated variable-speed peristaltic pump including a flexible pump tube, a hopper or other container for the mortar mounted above the pump tube and with an outlet connected to an inlet end of the pump tube, a device for vibrating the hopper or other container to cause mortar in the hopper or other container to flow through the outlet, and a mortar dispensing nozzle which has a handle to enable it to be held and directed by an operator and which

has a hose connecting the nozzle to an outlet end of the pump tube.

2. Apparatus according to claim 1, in which the pump is driven by an electric motor.

3. Apparatus according to claim 2, in which the motor is a variable speed motor.

4. Apparatus according to claim 2 or claim 3, in which the nozzle is provided with a trigger or other control member which controls a switch in the circuit of the motor to start and stop the pump.

5. Apparatus according to claim 2, in which there is an infinitely variable speed gear between the motor and the pump.

6. Apparatus according to any one of claims 2 to 5, in which the motor is reversible.

7. Apparatus according to any one of claims 2 to 6, in which the nozzle and the handle are in the form of a gun having a trigger which controls a switch which is connected to the motor by a cable so that operation of the trigger starts and stops the motor.

8. Apparatus according to claim 7 when dependent upon claim 6, in which the gun also has a control operated by a control knob and connected to the pump through the cable, operation of the control knob causing the motor to be run in either a forward or a reverse direction.

9. Apparatus according to any one of the preceding claims, in which the pump is mounted within a surrounding frame and the hopper is fixed to and forms a top of the frame.

10. Apparatus according to claim 9, in which the frame is provided with two wheels and a handle to enable the apparatus to be pushed or pulled by an operator running on the wheels.

11. Apparatus according to claim 1, substantially as described with reference to the accompanying drawings.