This invention relates to an elevator or lift. Lifts are used to move men and/or materials up and down of different floors of a building. Lifts consists of a carriage in which passengers are carried. A cable connected to the carriage and a prime mover moves the lift up and down of different floors of the building. Guide rails are provided to ensure smooth movement of the carriage. Suitable electric controls are provided inside the carriage to control the movement of the carriage. Normally electric motors are used as prime movers. Mechanical prime movers are used where there is no electricity. The entire system is housed in a lift chamber.

The above said lift system is open to the objection that cables used in the system get weaker day by day and gets damaged. Periodic replacement of cables is expensive.

Another objection is that more space and investment is required by the entire system besides a separate lift chamber. All the above said arrangements are more space consuming and escalate the cost factor if a lift has to be provided in a small residential building to move just one person at a time and if the lift is sparingly used. Especially aged and weak persons who can not climb the staircase need some alternative lift technology economically viable and less space consuming, and having less maintenance cost, to move up and down of different floors of a small building. The object of the present invention is to overcome the above said drawbacks.

I have found that:

Lifts or elevators can be built by using the existing principle of bolt and nut system, wherein a threaded nut if not allowed to rotate when a threaded bolt is rotated through it, and if the threaded bolt is fixed at both ends and just allowed to rotate only, then the nut gets a linear motion and the direction of motion of the nut is along the axis of the bolt, whether it is left or right handed threading system and the speed of the linear motion of the nut is directly proportional to the speed of rotation of the bolt and the pitch of the threading.

The invention will now be explained. It is a know fact that if a threaded bolt is rotated through a suitably threaded nut, and if the nut is held so that it does not rotate, then the nut gets a linear motion in a direction depending upon the nature of the thread whether it is a left handed or right handed thread. Vice versa, if the threaded nut is held so that it does not rotate and if a suitably threaded bolt is rotated, the bolt gets the linear motion.

The same principle can be used to build lifts or elevators to move men and/or materials. The movement will be along the axis of the bolt-nut system. If the threaded bolt is vertical, then the corresponding nut moves vertically if the bolt is fixed at both ends and allowed only to rotate using suitable bearings. This threaded bolt is called threaded shaft.

Now a lift carriage of any convenient dimension if attached to this nut, lift carriage also moves along with the nut. The dimension of the bolt-nut system can be technically designed to carry the required weight of the lift carriage connected to the nut. The speed and direction at which the carriage moves depends on the type and pitch of the thread used and the revolution per minute (rpm) at which the bolt is rotated. The bolt can be rotated using either an electrical or mechanical prime mover. Usually in small buildings suitable electric motors can be used to rotate the bolt. The lift carriage may be designed so small just to carry only one person either is standing or sitting position. It can also be used to carry some material also if needed at times.

Threaded shaft can be hollow or solid. Any number of hollow threaded shafts can be joined by internal threading at the ends similar to bore well digging shafts which can be extended to any required length. Counterweight is rendered unnecessary. That means elevators can be built for any required height in this technology also if required. This type of lift or elevator system needs very little space. The space can be provided at any required place of the building. This system can be used in small buildings especially by the weak and aged persons to move from one floor to another vertically. Horizontal movement is also possible if the shaft is placed horizontally. This system can also be designed to carry just one person at a time. Such a system requires very little space. For more weight carrying capacity of the carriage, more than one threaded shaft may be provided depending on the weight carrying capacity of the threaded shaft or the bolt-nut system. Also the thickness of the nut can be increased so that more number of its threading embraces the threading of the bolt. But all these shafts are to be synchronized
to rotate at equal speed. And the type of thread and pitch should be the same for all threaded shafts. Protective cover may be provided wherever necessary.

Split support system to the threaded bolt can be provided at regular places as required. That is whenever the nut reaches the support, it is opened and it closes soon after the nut moves away from the support. The split support system consists of custom built bearings, wherein the threaded bolt rotates inside the two halves of a circular bearing attached to two arms, held together by a spring, so that each arm is provided with a half bearing, forming a full circular bearing through which the threaded bolt rotates smoothly.

Whenever the nut firmly connected to the elevator carriage moving over the rotating threaded shaft, passes through the specially tapered portion made on both sides of the split supported bearing, the arms are opened up to allow the nut to pass through and when the nut leaves the split support system, the arms are closed by spring action so that the rotating threaded bolt is firmly held. More than one such split support system as required may be provided.

The split support system can also be provided to a parallel dummy shaft without thread to which the lift carriage with nut fixed to it, is connected, and the threaded shaft can be made just a driver shaft. One or more such dummy shafts as required housed in a casing may be provided which casing is/are firmly supported by the building or the structure where the elevator system is installed.

I claim:

1. Lifts or elevators can be built by using the existing principle of bolt and nut system, wherein a threaded nut if not allowed to rotate when a threaded bolt is rotated through it, and if the threaded bolt is fixed at both ends and just allowed to rotate only, then the nut gets a linear motion and the direction of motion of the nut is along the axis of the bolt, whether it is left or right handed threading system and the speed of the linear motion of the nut is directly proportional to the speed of rotation of the bolt and the pitch of the threading.

2. Lifts or elevators as claimed in claim 1, wherein split support system is provided either to the threaded shaft/s that is the driver shaft/s or to dummy shaft/s wherein the threaded or dummy shaft/s rotates smoothly inside the two halves of a circular bearing attached to two arms held together by a spring, so that each arm is provided with a half bearing, forming a full circular bearing,

3. Lifts or elevators as claimed in claim 1 &2, wherein any hard material such as metals, non metals, plastics or fiberglass is used to build the same.

4. Lifts or elevators as claimed in claim 1,2,&3 where in it is operated by using conventional or non conventional energy system/s or manually.