A portable backpack-borne power unit used for concrete vibration and consolidation, that is switchable between left-handed and right-handed applications. The power unit can transmit motor-generated power to a variety of tools with various power cables known in the art. For concrete vibration, power is transmitted to a vibrator that is immersed within green concrete. The instant design enables the power connection at the power unit to be secured on either side of the backpack, effectively facilitating either left-handed or right-handed operation.

A system, method, and apparatus for leveling concrete and similar materials. The automated, remotely controllable screed for leveling concrete can be used on any kind of sub-grade, it is lightweight and can be moved quickly to any location or floor level. It is highly accurate, and less labor intensive compared with the lightweight devices. It is all electrical mechanical. It is low noise. It is remotely controlled.

A concrete vibrator includes a frame, a strap coupled to the frame, a main housing supported upon the frame, and an electric motor coupled to the main housing. The concrete vibrator further comprises a flexible shaft having a first end coupled to the motor and an opposite, second end. The concrete vibrator further comprises a vibrator head coupled to the second end of the shaft, the vibrator head configured to receive torque from the motor and the shaft to cause the vibrator head to vibrate. The concrete vibrator is operable in a backpack configuration in which the strap is used to carry the concrete vibrator with the frame in a vertical orientation, and in a briefcase configuration in which the frame is supportable in a horizontal orientation.

A concrete vibrator can automatically change the rotational speed of a motor depending on the state of a vibrating tube. Under control by a controller, the concrete vibrator is operated in a normal mode in which the motor is supplied with driving power having a frequency to make the motor rotate at a rotational speed suitable for air bubble removal, or in an idling mode in which the motor is supplied with driving power having a frequency to make the motor rotate at a lower rotational speed than in the normal mode. The controller measures, per unit of time, a value of a current that is input to the controller or motor, compares a latest current value to a reference value calculated based on a past measurement value, and compares an absolute value of the comparison value to a threshold to grasp the state of the vibrating tube.

Provided is a concrete vibrator capable of automatically changing the rotational speed of a motor depending on the state of a vibrating tube and suitably avoiding overheating of the motor and a failure due to the motor overheating.

Under control of control means 8, the concrete vibrator is operated in a normal mode in which a motor 2 is supplied with driving power having a frequency that can make the motor 2 rotate at a rotational speed suitable for an air bubble removing process, or in an idling mode in which the motor 2 is supplied with driving power having a frequency that can make the motor 2 rotate at a rotational speed lower than the rotational speed in the normal mode. The control means 8 measures, per unit of time, a value of a current that is input to the control means 8 or the motor 2 to record the value in a memory, compares a latest current value to a reference value calculated on the basis of a past measurement value, and further compares an absolute value of the comparison value to a threshold to grasp the state of the vibrating tube so that an operation mode is suitably switched.

The invention comprises a concrete form. The form comprises a first concrete forming panel having a first primary surface adapted for forming and contacting plastic concrete and a second primary surface opposite the first primary surface; a layer of insulating material contacting and substantially covering the second primary surface of the first concrete forming panel; and an insulating blanket adjacent the first concrete forming panel. A method of using the concrete form is also disclosed.

The invention comprises a concrete form. The form comprises a first concrete forming panel having a first primary surface adapted for forming and contacting plastic concrete and a second primary surface opposite the first primary surface; a layer of insulating material contacting and substantially covering the second primary surface of the first concrete forming panel; and an insulating blanket adjacent the first concrete forming panel. A method of using the concrete form is also disclosed.

A vibration assembly for supporting a base pallet of a concrete pipe manufacturing machine, and a method for adjusting the assembly. The assembly includes an assembly frame, at least two pallet driving blocks supported for position adjustment relative to one another on the frame, and a vibrator connected to at least one of the pallet driving blocks. The pallet driving blocks transmit force to the base pallet of the concrete pipe manufacturing machine.

The invention comprises a concrete form. The form comprises a first concrete forming panel having a first primary surface adapted for forming and contacting plastic concrete and a second primary surface opposite the first primary surface; a layer of insulating material contacting and substantially covering the second primary surface of the first concrete forming panel; and an insulating blanket adjacent the first concrete forming panel. A method of using the concrete form is also disclosed.

The invention comprises a concrete form. The form comprises a first concrete forming panel having a first primary surface adapted for forming and contacting plastic concrete and a second primary surface opposite the first primary surface; a layer of insulating material contacting and substantially covering the second primary surface of the first concrete forming panel; and an insulating blanket adjacent the first concrete forming panel. A method of using the concrete form is also disclosed.