Description:FIELD OF INVENTION

The invention relates to the development of a machine for the qualitative assessment of the parameters of the printable concrete.

OBJECT OF INVENTION

There is no instrument is currently available to perform a qualitative assessment of printable concrete. Therefore, the concrete mix produced for the printable application can only be evaluated in a full-size 3D printer, which is not intended for the stated purpose. It is inefficient for evaluating printable concrete due to its overcapacity. Material, time, energy is wasted and with-it money. Also, it needs more space. Considering all these disadvantages of using a full-size 3D printer, there is clearly an increasing need and scope for simple and fastest way to qualitatively assess printable concrete and thereby increase the number of trial mix designs in more efficient manner.

SUMMARY OF INVENTION

The application of 3D printing of concrete structures is growing rapidly in the construction industry. There are exponential advances in the development of 3D printed concrete worldwide, both in printable concrete mixes and in concrete 3D printing machines. For the development of printable concrete for use in 3D printing applications, certain properties need to be ascertained when it is being printed, such as extrudability, buildability, shape retentivity, etc. Currently it is being evaluated by printing it in the full-scale 3D printer, which is an overcapacity and not meant for the said purpose. Because of the overcapacity, it is inefficient for the purpose of evaluation of printable concrete, which leads to waste of material, time, energy and in turn money. Clearly, there is a need for a machine for assessing the parameters of the concrete in a fastest and most efficient way so that a larger number of trial mixes can be assessed in short time and the concrete mix performance can be verified and standardised.

DRAWINGS

Fig. 1 - Conceptual illustration of portable assessment equipment for assessing printable concrete
Part no. Part names
11 Drive Unit
12 Augor Unit
13 Mix Feeding Passage
14 45SQ Orifice
15 Ø20 Orifice
16 Rotary Table
17 Belt/Chain Drive

Fig. 2 - Side view of portable assessment equipment for printable concrete

Fig. 3 - Front view of portable assessment equipment for printable concrete

Fig. 4 - Scehmatic view of an qualitative assessment equipment for printable concrete. As shown in Fig 4, the equipment consists of following five major units

Unit A – Height adjustable stand
Unit B – Concrete material extrusion system
Unit C – Rotating table
Unit D – Controller
Unit E – Human machine interface (HMI) docking station

Part no. Part names
Unit A
1 Column
2 Carriage
3 Hand wheel
4 Motor
5 Base
Unit B
6 Motor
7 Auger bit
8 Conical Hopper
Unit C
9 Rotating Tabletop
10 Motor
11 Gear
Unit D
12 Control panel
14 Control Cable
Unit E
13 HMI
15 Interface cable

Fig. 5 - Picture of Unit D control panel 12 in door open condition.

Fig. 6 - Illustration of major sections in the control panel 12
Part no. Part names
16 PLC
17 Motor Drives
18 Power supply
19 Terminal Connector

Fig. 7 - Block diagram of mechanical and electrical interconnection of printable concrete assessment machine

Fig. 8 - Side view of fully assembled printable concrete assessment machine

Fig. 9 - Front view of fully assembled printable concrete assessment machine

V. Description of Invention

In order to assess the performance of the printable concrete qualitatively, the assessment equipment shown in fig 4 must print the concrete in a single standard shape to a certain height. As previously stated, there are five major units involved in this operation. Each unit collaborates synchronously and sequentially to print the concrete on the rotating table. A circular layer will form as the material is dispensed from the Conical hopper to the rotating table. The auger mechanism rotates at a constant speed to help the concrete flow out of the Conical hopper. After completing one full circular layer, the Conical hopper moves to the next height and material dispensing continues for a subsequent layer over the previous layer. The layer printing process will be terminated once the user-defined numbers have been laid. Various qualitative assessments can be performed while the material is being printed, the layer is being formed, and after the entire cylindrical shape has been completed.

The function of Unit A in Fig 4 is to carry the unit B, move the unit B up and down at user-defined heights, and hold the unit B stably at any position along the height of the column 1. Column1 in unit A must be stiff enough to support the Conical hopper and other mechanisms in unit B. while unit B travel along the height of the column 1, it should be smooth, steady, and without vibration. During the operation, non-operation, and stop states of Unit A and Unit B, Unit B must be held firmly in place without sagging due to weight and gravity. Magnetic sensors mounted on the top and bottom of the column1 are used for equipment safety and to prevent movement beyond the limits of travel range. The magnetic sensors are positioned in such a way that when the carriage 2 approaches the sensor, it sends a high signal to Unit E, which sends a stop signal to Unit D, which stops the power to the motor.

Unit A shown in Fig 4 consists of column 1 which is to carry the load and hold the carriage 2 at desired height. Column 1 is attached to the base 5, which keeps the whole Unit A stand stable on floor. Base 5 can be freely placed on floor or fixed to the ground. Carriage 2 is mounted on the column 1 rack and pinion mechanism, which allows the smooth carriage movement along the column 1. Carriage 2 consists of a Hand wheel 3 to manually move up and down the carriage 2 to the desired height along the column 1in case of any failure of the automation system. Motor 4 is for moving the carriage 2 to the desired height along the column 1 for the control signals received from the unit 4. The function of Unit B shown in Fig 4 is to extrude the concrete material filled in the Conical hopper 8. The concrete material is filled manually in the conical Conical hopper. In order to ease and achieve the constant rate of extrusion of the material filled in conical hopper, the auger bit stirred at a constant speed with the help of the motor 6. The auger bit is fixed to the motor 6. Motor 6 speed is variable and maintained at set constant speed by controlling the power supply fed to it. The power supply fed to the motor 6 is controlled by unit D based on the commands received from the Unit E. the auger bit 7 is stirred at constant speed in single direction by the motor 6. The speed of the motor determines the rate at which the material is being extruded. When the motor is stopped, material extrusion will also be stopped. The conical hopper is made of metal and conical shape to take advantage of the the natural gravitational falling tendency of the material towards the outlet of the Conical hopper 8.

Unit B shown in Fig 4 consists of motor 6, Auger conveyor 7, and Conical hopper 8. The function of the Unit B is to extrude the material loaded on the conical hopper 8. Conical hopper 8 has the larger opening on the top and smaller opening at the bottom. The material is loaded on the top and material is extruded at the bottom. Motor 6 is mechanically fixed on the top of conical hopper 8 and connected to the Auger bit 7. Motor 6 rotates the Auger bit 7 at desired speed and in single direction set by the user in the unit E. Motor 6 direction is momentarily reversed if auger bit 7 struck or resists the motor rotation beyond its operating range and continues the normal operation in forward direction. Auger bit 7 rotates at the speed and direction at which motor rotates. Auger bit 7 blade formed with reduced diameter at each subsequent helical level while maintaining uniform spacing between the conical hopper wall 8. Conical hopper 8 in which the material to be extruded is filled manually And regularly as the material in the conical hopper 8 empties.
The function of the Unit C shown in Fig 4 is to rotate the tabletop 9 in a user set direction and at constant speed. The rotating tabletop 9 will be positioned below the conical hopper 8, So that the material extruded from the conical hopper 8 will be received by the rotating tabletop 9. While receiving the material, rotating tabletop 9 will be in constant rotational motion, So that a received material will be laid in a circular form. After forming one full circle, the rotating table stops and waits for next signal to rotate. The completion of one full circle is sensed by the magnetic sensor.

Unit C shown in Fig 4 Consists of Tabletop 9, Motor 10, and Gear 11. Tabletop 9 is fixed to the gear 11 can rotate clockwise or anti-clockwise at the speed and direction at which gear 11 rotates. On Tabletop 9, concrete filament extruded from the unit B is laid on the rotating tabletop 9. the function of the Gear 11 is to rotate the tabletop 9. Gear 11 is attached to the motor and rotates at reduced ratio of the motor speed. Motor 10 rotates at the speed based on the control signal received from the unit D. Magnetic sensor is fixed on unit D senses rotating tabletop 9 position. When the metal strip fixed on the rotating tabletop 9 passes by magnetic sensor, magnetic sensor senses and sends the signal to the unit D for next sequence of action.

The function of the Unit D shown in Fig4 is to generate control signals, control power supply and process the commands received from Unit E. It has got four major sections inside the control panel 12. PLC 16, motor Drives 17, power supply 18, and terminal connectors 19.
A. PLC 16 which runs the control logic programmed using ladder logic. As per the program loaded in the PLC, it scans the status of the Analog and digital signals, produces Analog, and digital signals. Also, it interrupts the routine operation based on the commands received from the Unit E.
B. Drive section 17 controls power supply to the motor based on the signals received from the PLC.
C. Power supply section 18 steps down the raw 230 VAC power to the suitable level required for the motor typical 80VAC, 6 amperes
D. Terminal connector 9 section joins outgoing wire and incoming wires.

Unit D shown in Fig 6 consists of PLC 16, drive section 17, Power supply section 18, and terminal connector section 19. Electrical power, control signal and digital signals are interconnected between the sections suitably.

The function of the Unit E shown in Fig4 is to display the status of the process and receive the human input through the touch screen. It has a touch screen display to show the status of the process graphically to the operator. The Unit E connected to PLC through the interface cable 15

Unit E shown in Fig4 consists of human machine interface (HMI) 13, and interface cable 15 connecting to Unit D.

Fig 7 shows the how each unit is interconnected with each other and performs a desired operation. The dashed line between Unit A and Unit B indicates that they are mechanically connected.

Unit E which consists of HMI 13, a human machine interface displays the process status graphically, sends, and receives commands and response over the interface cable 15 connected to the Unit D controller. Unit D process the commands received from Unit E and sends to the respective motor drive section 17 and PLC 16 to vary the signal and in turn the power output of the drives to control the speed and operation of the motor.

Unit D interfaced to Unit A, Unit B, and Unit C to send the power and signal output to the motor fixed on Unit A, B and C.

Unit B and Unit C are not physically or electrically interfaced, however the material extruded out of the Conical hopper 8 is laid on the rotating table in the Unit C.

As detailed above in one aspect the invention is for a system for assessing the performance of a printable concrete qualitatively comprising of five portions, first portion unit A – Height adjustable stand, second portion unit B – Concrete material extrusion system, third portion unit C – Rotating table, fourth portion unit D – Controller, and fifth portion unit E – Human machine interface (HMI) docking station wherein unit A is having a column (1), a base (5) onto which column (1) is fixed to ground. A carriage (2) mounted movably along the column (1) with a rack and pinion arrangement. A handwheel (3) adapted to manually move the carriage (2) along the column (1). A motor (4) adapted to move the carriage (2) along the column (1), magnetic sensors mounted on top and bottom of column (1) for limiting the motion of carriage (2) along the column (1).

Also the unit B is mounted on the moveable carriage (2) of unit A and the unit B is having a conical hopper (8) for receiving the concrete material for extrusion and printing with larger opening on top and smaller operating at bottom and an auger bit conveyer (7) operable with motor (6) for stirring the concrete material in single direction and rate of extrusion is based on motor speed and allowing the material downwardly to fall under gravitation out of the bottom outlet of the conical hopper (8), the said auger conveyer (7) adapted to rotate at constant speed and after completion of each full circular motion, the conical hopper is moved upward to the next height and material dispensing continued for a subsequent layer over the previous layer. Further the unit C is disposed beneath the unit B and unit C will have a rotating table top (9) in a selective desired direction and at a constant speed is disposed beneath the conical hopper (8) of unit B, so that material extruded from conical hopper (8) is dropped onto rotating table top (9) is received and laid in a circular form on the rotating table top (9), the rotating table top (9) is adapted to stop after every single rotation, which full circle rotation is sensed by magnetic sensor associated with table top (9), the said rotating table top (9) also has a metal strip indicator fixed on its surface, a gear (11) is associated with table top (9) to adapt the direction and speed rotation of table top (9) and also a motor (10) is associated with gear (11) thereby gear (11) rotates at reduced ratio of the motor speed.

The unit D is a control panel will have a control panel (12) with magnetic sensor adapted to sense the rotating table top (9) position through the metal strip indicator fixed on the rotating table top (9), and a control cable (14) associated with control panel (12).

The unit E is a control panel associated with unit A and unit E having HMI(13) with sensors to receive signal when carriage (2) of unit A is proximate to magnetic sensors of unit A, and generate corresponding power supply cut off signal to be transmitted to motor (10) of unit C, via interface cable (15).

The said arrangement is novel in that plurality of qualitative assessment can be performed layer by layer while the material is being printed, also assessed after the completion of entire cylindrical shape of the material to a certain selected desired height.

The invention displays following advantages :

1. The qualitative assessment equipment for printable concrete, the equipment comprising:
Unit A – Height adjustable stand comprising: Column 1, Carriage 2, Hand wheel 3, Motor 4, and Base 5
Unit B – Concrete material extrusion system comprising: Motor 6, Auger bit 7, and Conical hopper 8.
Unit C – Rotating table system: Rotating tabletop 9, Motor 10, and Gear 11.
Unit D – Controller comprising: Control panel 12, HMI 13, and control cable 14.
2. The Unit A, B C, and D as claimed in Claim 1 is modular. Modifications in unit is possible.
3. Unit B as claimed in Claim 1, extrude the material in round, Square or rectangle and any other form depending on the nozzle profile that was attached to the Conical hopper 8.
4. Unit C as claimed in claim 1, diameter of the rotating tabletop 9 may be varied to assess the quality of printable concrete material in the pattern at various diameter.
5. Unit C as Claimed in claim 1, can be replaced with the linear motion table to assess the quality of printable concrete material in the linear patterns and square patterns.
6. Unit C as claimed in claim 1 is modular. So, the table of different motion system can be used to assess the quality of the printable concrete in various complex patterns.
6. Unit B as Claimed in claim 1 has auger bit 7 with reduced blade diameter at each next helical levels and maintaining the uniform spacing between the wall of the conical hopper 8.

The invention thus as details has the following features and structural arrangement.

The examples and embodiments are provided only for the purpose of understanding and none of them shall limit the scope of the invention. All variants and modifications as will be envisaged by skilled person are within the spirit and scope of the invention.
, Claims:WE CLAIM :

1. A system for assessing the performance of a printable concrete qualitatively comprising of five portions :
- first portion unit A – Height adjustable stand,
- second portion unit B – Concrete material extrusion system,
- third portion unit C – Rotating table,
- fourth portion unit D – Controller, and
- fifth portion unit E – Human machine interface (HMI) docking station

wherein unit A is having

- a column (1),
- a base (5) onto which column (1) is fixed to ground,
- a carriage (2) mounted movably along the column (1) with a rack and pinion arrangement,
- a handwheel (3) adapted to manually move the carriage (2) along the column (1),
- a motor (4) adapted to move the carriage (2) along the column (1),
- magnetic sensors mounted on top and bottom of column (1) for limiting the motion of carriage (2) along the column (1).

wherein unit B is mounted on the moveable carriage (2) of unit A and unit B is having

- a conical hopper (8) for receiving the concrete material for extrusion and printing with larger opening on top and smaller operating at bottom,
- an auger bit conveyer (7) operable with motor (6) for stirring the concrete material in single direction and rate of extrusion is based on motor speed and allowing the material downwardly to fall under gravitation out of the bottom outlet of the conical hopper (8), the said auger conveyer (7) adapted to rotate at constant speed and after completion of each full circular motion, the conical hopper is moved upward to the next height and material dispensing continued for a subsequent layer over the previous layer.

wherein unit C is disposed beneath the unit B and unit C is having

- a rotating table top (9) in a selective desired direction and at a constant speed is disposed beneath the conical hopper (8) of unit B, so that material extruded from conical hopper (8) is dropped onto rotating table top (9) is received and laid in a circular form on the rotating table top (9),
- the rotating table top (9) is adapted to stop after every single rotation, which full circle rotation is sensed by magnetic sensor associated with table top (9), the said rotating table top (9) also has a metal strip indicator fixed on its surface,
- a gear (11) is associated with table top (9) to adapt the direction and speed rotation of table top (9),
- a motor (10) is associated with gear (11) thereby gear (11) rotates at reduced ratio of the motor speed.

wherein unit D is a control panel is having

- a control panel (12) with magnetic sensor adapted to sense the rotating table top (9) position through the metal strip indicator fixed on the rotating table top (9), and
- a control cable (14) associated with control panel (12)

wherein unit E is a control panel associated with unit A and unit E having HMI(13) with sensors to receive signal when carriage (2) of unit A is proximate to magnetic sensors of unit A, and generate corresponding power supply cut off signal to be transmitted to motor (10) of unit C, via interface cable (15).

the said arrangement characterized in that plurality of qualitative assessment can be performed layer by layer while the material is being printed, also assessed after the completion of entire cylindrical shape of the material to a certain selected desired height.