Title of Invention

A DEVICE FOR LOADING AND UNLOADING LPG CYLINDERS

Abstract

A device for loading and unloading LPG cylinders on to and from a vehicle comprising a movable boom assembly, the fore end of said boom being provided with gripper means, plurality of drive means for driving said boom in the desired direction sensor and control means for sensing and controlling boom position and movements and alignment means for providing desired alignment of said vehicle with the loading/unloading device.

Full Text

This invention relates to a device for loading and unloading LPG cylinders and is particularly useful in unloading empty cylinders from and loading filled cylinders on to vehicles such as trucks. Loading and unloading of LPG cylinders from LPG filling and bottling plants of various oil companies for transhipment to various consumer outlets are potentially hazardous. As a domestic fuel, LPG is very popular, rated very high and is in great demand. To satisfy the ever increasing consumer requirements, higher production output is being constantly aimed at by the industry. Greater emphasis is now attributed to human welfare and safety, particularly with respect to handling of potentially hazardous materials like LPG. Automation in various fields of any industry would result in higher production rate and ensures human welfare and safety. Cylinders of 14.2 kg capacity and 19kg capacity are used to fill liquified petroleum gas. By far, a large proportion is meant for the domestic consumers and as such the bulk filling is for cylinders of 14.2 kg capacity. However, both the types of cylinders are required to be transported to meet random consumer demands. Presently, trucks are loaded and unloaded manually with the help of a telescopic conveyor. LPG cylinders are manually picked up from the conveyor and loaded on to the truck in the desired nesting pattern. Apart from the risk factors involved in the handling of hazardous material, this method is time consuming and labour intensive, further escalating the cost of the product. This further emphasises the need for automation in the particular field. The main object of this invention is to develop a device for automatic handling of LP6 cylinders and arranging the loaded cylinders in a desired pattern. A robotically controlled moving cantilever arrangement is the main feature of the device. The arm of the cantilever is movable in the desired direction with the help of drive means. Grippers are positioned at one end of the cantilever arm which consists of two booms. The fore-end of the boom carries the gripper assembly mounted on a cross-beam. Drive means and control means are provided to controllably drive the boom as .' ■ *■• desired. The grippers will grip the cylinders to be loaded/unloaded and the boom arm will move to the desired direction as commanded by the control means. Aligning means such as a sensor connected to the control system which aligns the truck where loading or unloading is to be effected. The device for loading and unloading LPG cylinders on to and from a vehicle according to this invention comprises a movable boom assembly, the fore end of said boom being provided with gripper means, plurality of drive means for driving said boom in the desired direction, sensor means and control means * for sensing and controlling boom position and movements and alignment means for providing desired alignment of said vehicle with the loading/unloading device. This invention will now be described with reference to the figures in the accompanying drawings: Fig. 1 shows the right hand longitudinal elevation view of the device in alignment with the platform of the truck. Fig. 2 is a sectional view of the hoist drive and Fig. 3 is a plan view showing the grouper unit for grouping the desired number of LPG cylinders and gripper means for gripping each cylinder thus grouped. The device and its operation will now be described with reference to the above drawings. Reference number 1 stands for an LPG cylinder moving on a existing plant conveyor and numeral 2 shows an LPG cylinder on a grouper held by the gripper means 3. 5 indicates the floor of the truck on which the cylinders are to be loaded. The hoist drive means and the boom drive means are indicated by reference numerals 8, 8', 11, 11' and 10. Numerals 7 and 7' represent the gantry stand for supporting and fixing the drive means on to platform 4. Aligning means is indicated by numeral 12 which senses and positions the truck platform with the base platform of the device. In fig. 2 showing the sectional view of the hoisting mechanism, reference numeral 6 indicates the top pulley, 7 the gantry stand, and numeral 13 the bottom flange for fixing it on to the platform. Numeral 8 represents the booms which is provided with bearing housing. Numerals 16 indicates bearings preferably nylon or polyurethane bearings. Reference numeral 11 is the bottom drive pulley and reference numeral 15 shows the drive rack tooth for the boom 8 while 18 is a vertical slide plate for hoisting the boom. Reference numeral 19 indicates means such as a counter weight for regulating the boom movement. Fig. 3 shows a sectional view showing the grouper means (4) the boom (8) with a cross beam having gripper means attached to LPG cylinders. Reference numer 2 shows the LPG cylinder in the plant conveyor. Numerals 9 and 15 are bearing housing and a sectional view of the side runner respectively. Numerals 12, 18 and 19 are parts already discussed with reference to figs 1 and 2. Control system and power source are not shown in the drawings. The boom assembly may consist of twin booms with a cross beam joint at the fore end thereof. This cross beam carries the gripper assembly. The boom assembly is supported on two side runners welded on each of the boom. This enables continous transfer of load to the bearing surfaces through out the processes of forward movement with the loaded LP6 cylinders and devoid of load during reversal and forward movement during truck unloading and reversal of load with empty cylinders. The booms are provied with gear teeth attached to the underside which mesh with driving gear. The booms are preferably light with a reqtangular cross section, the fore end being the smallest side of the rectangle. The size of the rectangle progressively increases only towards the top towards the rear end which is the biggest side of the rectangle. Thus the bottom of the boom is uniformly level while the top and sides form a uniform taper. Supporting stands are provied for the boom assembly and transfers the load on the beams to the platform ground. The bearing housing consists of two sets of oppositely N * - Xi facing sections housing bearing material. These elements have provision for entry of compressed air and is provided with sealing arrangement to prevent rapid escape of the injected air which enables gliding movement of the boom. Grippers are shaped to fit the contour of the LPG cylinder * so as to wrap the cylinder around the top and bottom curvatures. A clamping means is provided on each gripper to ensure firm grip on the cylinder during movement. The drive means consist of boom drive, hoist drive and cross drive. Boom drive consists of gear that meshes with a rack on the underside of the boom. This gear is housed in a gear box provided with a shaft that extends to one side. This shaft is supported by hermitically sealed ball bearings on the extended portion of the shaft. The shaft has splines which carry a worm wheel driven by a worm shaft. A flange coupler one end of the worm shaft with an electrical servo motor. Hoist drive consists of pulleys and counter balance arrangement or by ball guide lead screws. Idler pulleys and bearings are provided for the hoist drive assembly. These pulleys are driven by a worm wheel and shaft arrangement which is coupled to an electrical servo motor. Four such hoist drive assemblies are preferably provided. Each drive assembly is mounted on a stand and is synchronised by a control unit. Cross drive assembly may be a sliding mechanism provided with conventional lever linkage. This assembly is mounted on the cross beam of the boom assembly. Sensors are provided for advising the control unit with regard to the position velocity and sense of direction of the various elements in motion. Servo motors are provided with digital readouts encoders. The control unit consists of a computer system provided with control functions and programs for a variety of nesting patterns. Computer has facility to control the operation in accordance with the sensor feed back. Various outputs are actuated and commanded by the computer system. It is also possible to interface with human operation by way of membrane key board or voice command and communication. The grouper unit consists of of frame work, capable of receiving at" l-e^ast six LPG cylinders from the chain conveyors of the plant. The grouper arrays the LPG cylinders and enables the gripper assembly on the end of the boom to pick up a group of at least 8 LPG cylinders or to place them during loading and unloading. The grouper assembly is positioned across the longitudinal axes of the conveyor and is driven pneumatioally to be parallel with the conveyor when receiving or discharging LPG cylinders. Aligner unit consists of a set of sensors for receiving signals from a truck aligned with it. The sensors feed back signals to the control unit which drives the motors or pneumatic cylinders to align the truck with respect to the conveyor axes and arm of the boom assembly. Though this invention has been described hereinbove with respect to specific embodiment, modifications and alterations known to persons skilled in the art are not excluded from the scope and ambit of the appended claims. WE CLAIM: 1. A device for loading and unloading LPG oylindders on to and from a vehicle comprising a movable boom assembly, the fore end of said boom being provided with gripper means, plurality of drive means for driving said boom in the desired direction, sensor means and control means for sensing and controlling boom position and movements and alignment means for providing desired alignment of said vehicle with the loading/unloading device. 2. The device as claimed in claim 1 wherein a grouper means are provided for grouping and arranging LPG oylindders for loading and unloading. 3. The device as claimed in claim 2 wherein the grouper means consists of frame members. 4. The device as claimed in any of the preceding claim wherein said boom assembly oonsists of twin beams with a cross ■•, beam Joint at the forends. ■■ -^ 5. The device as clailned in any of the claims 1-4 wherein the grippers are provided on the cross beam of the boom assembly. 6. The device as claimed in claim 8 wherein the grippers are shaped to fit the contour of an LPG cylinder and are provided with clamp means. 7. The device as claimed in claim 1 wherein the drive means are hoist drive, boom drive and cross drive means. 8. The device as claimed in claim 7 wherein the hoist and boom drive means consist of conventional gear, shaft, pulleys, worm wheel and worm shaft assemblies drivable pneumatically or electrically by servomotors coupled to ball guide screws. 9. The device as claimed in claim 1 wherein the cross drive assembly is mounted on the cross beam of said boom and consists of conventional sliding and lever arrangement. 10. The device as claimed in any of the preceding claims wherein the drive assemblies are provided with appropriate bearings. 11. The device as claimed in claim 1 wherein the control means consists of a computer, programmed to receive signals from said sensing means and/or to control the operation. 12. The device as claimed in claim 1, wherein the alignment *> means consists of sensors for receiving signals from the vehicle and transmitting signals to said control means, 13. The device as claimed in claim 1 wherein the booms have a rectangular cross section, the fore end being the smallest side of the rectangle, the size of the rectangle progressively increasing at the top towards the rear which is the biggest side of the rectangle. 14. A device for loading and unloading LP6 cylinders substantially as herein described with reference to the figures in the accompanying drawings.

Documents:

143-mas-1999-abstract.pdf

143-mas-1999-claims filed.pdf

143-mas-1999-claims granted.pdf

143-mas-1999-correspondnece-others.pdf

143-mas-1999-correspondnece-po.pdf

143-mas-1999-decription(complete)granted.pdf

143-mas-1999-description(complete)filed.pdf

143-mas-1999-drawings.pdf

143-mas-1999-form 1.pdf

143-mas-1999-form 19.pdf

143-mas-1999-form 26.pdf

143-mas-1999-form 3.pdf