阅读说明：本技术 一种智能充电设备及其使用方法 (Intelligent charging equipment and use method thereof ) 是由 张健华 符子娟 于 2021-09-03 设计创作，主要内容包括：本发明公开了一种智能充电设备,包括大壳体,所述大壳体内设有充电机模块、充电机构；所述充电机模块通过固定支架固定安装在大壳体内；所述充电机构沿水平第一方向可移动设置在大壳体内,其部分伸出大壳体用于与待充电的AGV车辆连接以供电；所述充电机构上安装有接近开关。当AGV车辆到达充电位置后,充电机构中的充电铜块伸出大壳体,通过接近开关辅助判断充电铜块到位与否,充电机模块发出到位信号,充电机构开始给AGV车辆充电。该接近开关确保了铜块与AGV车体充电接触面的接触可靠性,减小接触电阻从而避免大电流充电中的热损耗风险,可有效延长设备的使用寿命。(The invention discloses intelligent charging equipment which comprises a large shell, wherein a charger module and a charging mechanism are arranged in the large shell; the charger module is fixedly arranged in the large shell through a fixed support; the charging mechanism is movably arranged in the large shell along a horizontal first direction, and part of the charging mechanism extends out of the large shell and is used for being connected with an AGV to be charged so as to supply power; and the charging mechanism is provided with a proximity switch. When the AGV vehicle reaches the charging position, the charging copper block in the charging mechanism extends out of the large shell, whether the charging copper block is in place or not is judged by the aid of the proximity switch, the charger module sends a place signal, and the charging mechanism starts to charge the AGV vehicle. The proximity switch ensures the contact reliability of the contact surface of the copper block and the AGV body, reduces the contact resistance, avoids the heat loss risk in large-current charging, and can effectively prolong the service life of the equipment.)

1. The utility model provides an intelligent charging equipment, includes big casing (1), its characterized in that: a charger module (2) and a charging mechanism are arranged in the large shell (1); the charger module (2) is fixedly arranged in the large shell (1) through a fixed support; the charging mechanism is movably arranged in the large shell (1) along a horizontal first direction, and part of the charging mechanism extends out of the large shell (1) and is used for being connected with an AGV to be charged so as to supply power; a proximity switch (3) is arranged on the charging mechanism;

the charging mechanism further comprises an electric driving system mounting supporting plate (4), a translational electric driving device (5), a copper head telescopic L-shaped support metal plate (6), an insulating plate (7) and a charging copper block (8); the electric drive system mounting support plate (4) is detachably and fixedly mounted in the large shell (1), and the translational electric drive device (5) is mounted on the electric drive system mounting support plate (4); the copper head telescopic L-shaped bracket metal plate (6) is fixedly connected with the translational electric driving device (5); the charging copper block (8) is fixedly connected to the insulating plate (7) through a copper block sleeve casting (9), and the insulating plate (7) and the copper head telescopic L-shaped support metal plate (6) are arranged on the insulating plate; the translational electric driving device (5) is used for controlling the copper head to stretch out and draw back the L-shaped support metal plate (6) to extend out or retract into the large shell (1) through controlling the copper head to translate in the horizontal first direction.

2. The intelligent charging device of claim 1, wherein: the insulation board (7) is fixedly connected with the copper head telescopic L-shaped support metal plate (6) through an L-shaped support front protection frame metal plate (6-1), and a proximity switch fixing support (6-2) is fixedly connected to the side of the L-shaped support front protection frame metal plate (6-1) and used for installing the proximity switch (3).

3. The intelligent charging device of claim 1, wherein: the translational electric driving device (5) comprises a motor (51), a motor driving box (52), a sliding block (53), a module sliding rail (54) and a travel switch; the lower part of the module sliding rail (54) is fixedly connected to an electric drive system mounting supporting plate (4) through a plurality of sliding rail feet (55), the sliding block (53) is connected to the module sliding rail (54) in a sliding mode along a horizontal first direction, and the motor (51) operates to drive the sliding block (53) to move; the motor driving box (52) is used for controlling the operation of the motor, and the travel switch is used for limiting the moving travel of the sliding block (53).

4. The intelligent charging device of claim 3, wherein: the tail end of the module sliding rail (54) is fixedly connected with a sliding rail corner connecting piece (56) and a sliding rail corner fitting (57) and used for limiting the moving initial position of the sliding block (53).

5. The intelligent charging device of claim 4, wherein: a temperature sensor is arranged on the charging copper block (8), and a temperature control plate (10) is arranged on the electric drive system mounting supporting plate (4); when the temperature sensor detects that the temperature of the charging copper block (8) exceeds a limit value, a signal is sent to the temperature control board (10), the temperature control board (10) sends an over-temperature signal to the charger module (2), the CPU controls the stopping of charging and drives the translational electric driving device (5) to withdraw the charging copper block (8), and the charging is started again after the temperature of the charging copper block (8) is recovered.

6. The intelligent charging device of claim 1, wherein: a large shell door (1-1) and a bakelite door plate (1-2) are arranged on the side of the large shell (1); the large shell door (1-1) is positioned at the rear side of the horizontal first direction; the bakelite door plate (1-2) is positioned on the front side in the horizontal first direction and is made of an insulating material; the bakelite door panel (1-2) is opened when the charging copper block (8) extends out of the large shell (1), and the bakelite door panel (1-2) is closed when the charging copper block (8) retracts into the large shell (1).

7. The intelligent charging device of claim 1, wherein: the large shell (1) is also provided with a power supply connector (1-4) and a locking waterproof connector (1-5) which are used for being connected with an external power line.

8. The intelligent charging device of claim 1, wherein: the top of the large shell (1) is also provided with a wireless box (12).

9. A method of using the intelligent charging apparatus of claim 1, wherein:

the method comprises the following steps:

step 100, charging the AGV vehicle;

200, enabling the AGV to reach a charging position of the intelligent charging device;

300, the AGV vehicle sends a vehicle in-place signal to the intelligent charging device;

step 400, extending out a charging copper block (8) of a charging mechanism on the intelligent charging device;

500, the charging copper block (8) stretches out to be in place, and the charging mechanism sends out a charging copper block (8) in-place signal;

step 600, the AGV sends a charging permission signal, and a charging brush plate of the AGV attracts a charging copper block (8);

step 700, the intelligent charging device detects the battery voltage of the AGV, receives the charging requirement of the AGV and outputs corresponding requirement data according to the instruction requirement of the AGV;

step 800, the intelligent charging device starts to charge the AGV;

step 900, the AGV vehicle reports an error and sends a charging stopping instruction or the battery is fully charged;

step 1000, stopping charging by the intelligent charging device, and withdrawing the charging copper block (8);

step 1100, the AGV vehicle intelligent charging device starts to work.

10. The use method of the intelligent charging device according to claim 9, wherein: the AGV vehicle error reporting in the step 900 comprises that the surface temperature of the charging copper block (8) exceeds a limit value, the battery voltage of the AGV vehicle is abnormal, and the charging copper block (8) is not in contact with a charging brush plate of the AGV vehicle or is not in place.

11. The use method of the intelligent charging device according to claim 10, wherein: after the AGV vehicle reports errors because the surface temperature of the charging copper block (8) exceeds the limit value and sends a charging stopping instruction, the intelligent charging device stops charging and withdraws the charging copper block, and the step 300 is started again after the surface temperature of the charging copper block (8) is recovered.

Technical Field

The invention relates to intelligent charging equipment of a mobile robot and a using method thereof, belonging to the technical field of robot charging.

Background

Now, storage unmanned transportation is becoming a development trend, so that the application of a transport type AGV (i.e. an automatic guided vehicle) in storage transportation is becoming more and more extensive. The AGV uses a storage battery as running power, and mostly adopts an automatic charging working mode; through installing the brush board that charges on the automatic guide car promptly, the last charging electrode of electric pile is filled in the contact, carries out the operation of charging.

The charging methods currently adopted by AGV vehicles generally include three types: firstly, the charging is carried out from the bottom of the AGV vehicle, the charging pile of the charging mode is very inconvenient to install, and the ground needs to be excavated for wiring and charging equipment needs to be installed; secondly, the charging mode from the side of the AGV vehicle often causes the damage of the robot body and the charging device due to the overlarge running position deviation of the mobile robot and the hard collision of the mobile robot with the charging pile, and influences the normal work of the robot; thirdly, carry out the mode of charging from AGV vehicle top, the AGV vehicle drives into the charging area when its top brush that charges and fills the electric brush piece friction on the electric pile and begins to charge to the car is stationary, this kind of mode butt joint pressure is uncontrollable, and because the brush piece that charges often rubs and causes the damage easily, long-time use charges the electric brush piece and leads to its conducting surface wearing and tearing, the plane can slowly wear into the cambered surface, lead to charging area of contact little, the overcurrent is not enough, the heavy current charges for a long time and generates heat and arouses the potential safety hazard, and the brush piece that charges sets up outside charging device alone, the integration level is relatively poor, unnecessary circuit heat loss can be leaded to extra circuit, thereby certain potential safety hazard and construction wiring are loaded down with trivial details, metallic conductor exposes also has the potential safety hazard in the air.

Accordingly, an intelligent charging device and a method for using the same are provided to solve the above problems.

Disclosure of Invention

The invention aims to: the utility model provides an intelligent charging equipment and application method thereof, collect multiple functions in an organic whole and small simple to operate, be applicable to most warehouse AGV vehicle and charge, solved present AGV vehicle intelligent charging problem.

The technical scheme of the invention is as follows: an intelligent charging device comprises a large shell, wherein a charger module and a charging mechanism are arranged in the large shell; the charger module is fixedly arranged in the large shell through a fixed support; the charging mechanism is movably arranged in the large shell along a horizontal first direction, and part of the charging mechanism extends out of the large shell and is used for being connected with an AGV to be charged so as to supply power; a proximity switch is arranged on the charging mechanism; the charging mechanism further comprises an electric driving system mounting supporting plate, a translational electric driving device, a copper head telescopic L-shaped support metal plate, an insulating plate and a charging copper block; the electric drive system mounting support plate is detachably and fixedly mounted in the large shell, and the translation electric drive device is mounted on the electric drive system mounting support plate; the copper head telescopic L-shaped support metal plate is fixedly connected to the translational electric driving device; the charging copper block is fixedly connected to the insulating plate through a copper block sleeve casting, and the insulating plate and the copper head telescopic L-shaped support metal plate are connected with the insulating plate; the translational electric driving device controls the copper head to stretch out or retract into the large shell through controlling the copper head to stretch out and retract into the large shell through the horizontal first direction translation of the L-shaped support metal plate.

Preferably, the insulation board pass through L shape support front fender frame panel beating with the flexible L shape support panel beating fixed connection of copper head, L shape support front fender frame panel beating side fixedly connected with proximity switch fixed bolster for install proximity switch.

Preferably, the translational electric driving device comprises a motor, a motor driving box, a sliding block, a module sliding rail and a travel switch; the lower part of the module sliding rail is fixedly connected to an electric drive system mounting supporting plate through a plurality of sliding rail feet, the sliding block is connected to the module sliding rail in a sliding mode along a horizontal first direction, and the sliding block is driven to move by the operation of the motor; the motor driving box is used for controlling the motor to operate, and the travel switch is used for limiting the moving travel of the sliding block.

Preferably, the tail end of the module slide rail is fixedly connected with a slide rail corner connecting piece and a slide rail corner fitting for limiting the initial moving position of the slide block.

Preferably, the charging copper block is provided with a temperature sensor, and the electric drive system mounting supporting plate is provided with a temperature control plate; when the temperature sensor detects that the temperature of the charging copper block exceeds a limit value, a signal is sent to the temperature control board, the temperature control board sends an over-temperature signal to the charger module, the CPU controls the charging to be stopped, the translational electric driving device is driven to withdraw the charging copper block, and the charging is started again after the temperature of the charging copper block is recovered.

Preferably, a large shell door and a bakelite door plate are arranged on the side of the large shell; the large shell door is positioned at the rear side of the horizontal first direction; the bakelite door plate is positioned on the front side in the horizontal first direction and is made of an insulating material; the bakelite door plate is opened when the charging copper block extends out of the large shell, and is closed when the charging copper block retracts into the large shell.

Preferably, the large shell is further provided with a power connector and a locking waterproof connector for connecting with an external power line.

Preferably, a wireless box is further installed on the top of the large shell.

A use method of the intelligent charging device comprises the following steps:

step 100, charging the AGV vehicle;

200, enabling the AGV to reach a charging position of the intelligent charging device;

300, the AGV vehicle sends a vehicle in-place signal to the intelligent charging device;

step 400, extending out a charging copper block of a charging mechanism on the intelligent charging device;

500, the charging copper block is stretched out in place, and the charging mechanism sends out a charging copper block in-place signal;

step 600, the AGV sends a charging permission signal, and a charging brush plate of the AGV attracts a charging copper block;

step 700, the intelligent charging device detects the battery voltage of the AGV, receives the charging requirement of the AGV and outputs corresponding requirement data according to the instruction requirement of the AGV;

step 800, the intelligent charging device starts to charge the AGV;

step 900, the AGV vehicle reports an error and sends a charging stopping instruction or the battery is fully charged;

step 1000, stopping charging by the intelligent charging device, and recovering the charging copper block;

step 1100, the AGV vehicle intelligent charging device starts to work.

Preferably, the AGV vehicle error report includes the surface temperature of the charging copper block exceeding a limit value, the voltage of the battery of the AGV vehicle being abnormal, the charging copper block not contacting the charging brush of the AGV vehicle or the contact not being in place.

Preferably, after the AGV reports an error when the surface temperature of the charging copper block exceeds the limit value and sends a command to stop charging, the intelligent charging device stops charging, and withdraws the charging copper block, and step 300 is restarted after the surface temperature of the charging copper block is recovered.

The invention has the advantages that:

1. the charging mechanism is integrated in the large shell of the charging equipment, so that the charging copper block can be protected.

2. When the AGV reaches the charging position, a charging copper block in the charging mechanism extends out of the large shell, whether the charging copper block is in place or not is judged by the aid of the proximity switch, the charger module sends a place signal, and the charging mechanism starts to charge the AGV; proximity switch has ensured the contact reliability of copper billet and AGV automobile body contact surface that charges, thereby reduces contact resistance and avoids the heat loss risk in the heavy current charges, can effectively prolong the life of equipment.

3. The temperature sensor is arranged to monitor the surface temperature of the charging copper block when the large current runs, when the temperature sensor detects that the temperature of the charging copper block exceeds a limit value, a signal is sent to the temperature control board, the temperature control board sends an over-temperature signal to the charger module, the CPU controls the stopping of charging, the translation electric driving device is driven to withdraw the charging copper block, the charging is started again after the temperature of the charging copper block is recovered, and potential safety hazards can be effectively avoided.

4. Because the electric drive system mounting support plate is detachably and fixedly mounted in the large shell, the whole charging mechanism can be detached from the equipment. If the power supply system is suddenly powered off during the operation of the AGV vehicle, the AGV vehicle cannot drive the intelligent charging equipment to be charged, the large shell door can be opened, the charging mechanism can be detached from the equipment, and the AGV vehicle can be carried to the position to be manually intervened to be charged, so that special manual charging equipment does not need to be equipped on the site.

5. The use method of the intelligent charging device is simple to operate, and the AGV can be safely and effectively charged.

Drawings

The invention is further described with reference to the following figures and examples:

FIG. 1 is an exploded view of the structure of the present invention;

FIG. 2 is an exploded view of the charging mechanism of the present invention;

FIG. 3 is a schematic diagram of a charging state structure of a charging mechanism of the intelligent charging apparatus according to an embodiment;

FIG. 4 is an enlarged view taken at A in FIG. 3;

FIG. 5 is a flowchart illustrating operation of the intelligent charging apparatus according to an exemplary embodiment;

wherein: 1. a large housing; 1-1, a large shell door; 1-2, a bakelite door plate; 1-3, a hinge; 1-4, a power connector; 1-5, locking a waterproof joint; 2. a charger module; 3. a proximity switch; 4. mounting a supporting plate of an electric drive system; 5. a translational electric drive; 51. a motor; 52. a motor drive box; 53. a slider; 54. a module slide rail; 55. a slide rail foot; 56. a slide rail corner connector; 57. a slide rail corner fitting; 6. a copper head telescopic L-shaped bracket metal plate; 6-1, forming a metal plate of the front protection frame of the L-shaped bracket; 6-2, a proximity switch fixing support; 7. An insulating plate; 8. charging the copper block; 9. casting a copper block sleeve; 10. a temperature control plate; 11. an air switch; 12. a wireless box.

Detailed Description

The invention will now be further elucidated with reference to the drawing. (hereinafter, with respect to the orientation, it is based on the direction in which the charging copper block is stretched, wherein "front" refers to the direction in which the charging copper block is stretched out, and "rear" refers to the direction in which the charging copper block is retracted).

The invention discloses intelligent charging equipment, which is shown in the attached figures 1-4 and comprises a large shell 1, wherein a charger module 2 and a charging mechanism are arranged in the large shell 1; the charger module 2 is fixedly arranged in the large shell 1 through a fixed support; the charging mechanism is movably arranged in the large shell 1 along a horizontal first direction, and part of the charging mechanism extends out of the large shell 1 and is used for being connected with an AGV to be charged so as to supply power; and the charging mechanism is provided with a proximity switch 3. The charging mechanism further comprises an electric driving system mounting supporting plate 4, a translational electric driving device 5, a copper head telescopic L-shaped support metal plate 6, an insulating plate 7 and a charging copper block 8; the electric driving system mounting support plate 4 is detachably and fixedly mounted in the large shell 1, and the translational electric driving device 5 is mounted on the electric driving system mounting support plate 4; the copper head telescopic L-shaped bracket metal plate 6 is fixedly connected with the translational electric driving device 5; the charging copper block 8 is fixedly connected to the insulating plate 7 through a copper block sleeve casting 9, and the insulating plate 7 and the copper head telescopic L-shaped support metal plate 6 are arranged on the insulating plate; the translational electric driving device 5 is used for controlling the copper head to stretch out and draw back the charging copper block 8 to the large shell 1 by controlling the copper head to stretch out and draw back the L-shaped support metal plate 6 in the horizontal first direction. The insulation board 7 is fixedly connected with the copper head telescopic L-shaped support metal plate 6 through an L-shaped support front protection frame metal plate 6-1, and a proximity switch fixing support 6-2 is fixedly connected to the side of the L-shaped support front protection frame metal plate 6-1 and used for installing the proximity switch 3. According to the device, a charging mechanism is integrated in a large shell of the charging device, a charging copper block can be protected, when an AGV reaches a charging position, a charging copper block 8 in the charging mechanism extends out of the large shell 1, whether the charging copper block 8 is in place or not is judged by the aid of a proximity switch 3, a charger module sends an in-place signal, and the charging mechanism starts to charge the AGV; the proximity switch ensures the contact reliability of the charging contact surface of the charging copper block and the AGV body, reduces contact resistance, avoids heat loss risks in large-current charging, and can effectively prolong the service life of equipment. Because the electric drive system mounting support plate is detachably and fixedly mounted in the large shell, the whole charging mechanism can be detached from the equipment. If the power supply system is suddenly powered off during the operation of the AGV vehicle, the AGV vehicle cannot drive the intelligent charging equipment to be charged, the large shell door can be opened, the charging mechanism can be detached from the equipment, and the AGV vehicle can be carried to the position to be manually intervened to be charged, so that special manual charging equipment does not need to be equipped on the site.

For further explanation of the above technical solution, the translational electric driving device 5 includes a motor 51, a motor driving box 52, a sliding block 53, a module sliding rail 54 and a travel switch; the lower part of the module slide rail 54 is fixedly connected to the electric drive system mounting plate 4 through a plurality of slide rail feet 55, the slide block 53 is connected to the module slide rail 54 in a sliding manner along a horizontal first direction, and the motor 51 operates to drive the slide block 53 to move; the motor driving box 52 is used for controlling the operation of the motor, and the travel switch is used for limiting the moving travel of the slider 53. The rear end of the module slide rail 54 is fixedly connected with a slide corner connector 56 and a slide corner fitting 57 for limiting the initial moving position of the slide block 53. The structural design of travel switch, slide rail corner connecting piece 56 and slide rail corner accessory 57 in this translation electricity drives the device, has ensured the invariable flexible stroke of copper billet 8 that charges, and then has guaranteed that the contact force of copper billet 8 and AGV vehicle charging end is invariable, can effectively prolong battery charging outfit's life.

To the further explanation of above-mentioned technical scheme, be equipped with temperature sensor on the copper billet 8 charges, install the control by temperature change board 10 on the system mounting supporting plate 4 of electricity drives, when temperature sensor detects that the copper billet 8 temperature that charges surpasss the limit value, give control by temperature change board 10 with signal transmission, control by temperature change board 10 sends the overtemperature signal to the machine module 2 that charges, CPU control stops charging to drive translation electricity and drive device 5 and withdraw the copper billet 8 that charges, wait to charge and start again after the copper billet 8 temperature resumes and charge, can effectively avoid the potential safety hazard.

Further explaining the technical scheme, a large shell door 1-1 and a bakelite door plate 1-2 are arranged on the side of the large shell 1; the large shell door 1-1 is positioned at the rear side of the horizontal first direction; the bakelite door plate 1-2 is positioned on the front side in the horizontal first direction and is made of an insulating material; the bakelite door plate 1-2 is hinged on the large shell 1 through a hinge 1-3. When the charging copper block 8 extends out of the large shell 1, the bakelite door panel 1-2 is pushed away passively, and when the charging copper block 8 retracts into the large shell 1, the bakelite door panel 1-2 is closed automatically under the effect of the resilience force of the hinge 1-3. This structure can effectively protect copper billet 8 that charges, avoids the dust to get into the inside of copper billet 8 that charges when not charging to contact failure's probability when charging AGV vehicle after reducing long-time the use.

Further, the large housing 1 is further provided with a power connector 1-4 and a locking waterproof connector 1-5 for connecting with an external power line, so that the installation and wiring are convenient.

To explain further, a wireless box 12 is further installed on the top of the large housing 1 for receiving and transmitting wireless signals.

Further, the electric drive system mounting support plate 4 is provided with the air switch 11, the air switch 11 is powered off when being used for equipment maintenance, the design is very humanized, and the later maintenance of the equipment is convenient.

The intelligent charging device is mainly used for intelligent charging of transport type AGV vehicles in unmanned storage. This AGV intelligence battery charging outfit, when the AGV vehicle was close to and charges, motor 51 drove slider 53 and drives copper billet 8 that charges along module slide rail 54 horizontal migration and stretch out from bakelite door plant 1-2, with the AGV vehicle connection that waits to charge with the power supply, waits that the AGV vehicle finishes charging, and motor 51 reversal drives copper billet 8 that charges and retracts to initial position, bakelite door plant 1-2 self-closing.

The method for using the intelligent charging device according to the above embodiment includes the following steps:

step 100), the AGV vehicle needs to be charged;

step 200), enabling the AGV to reach the charging position of the intelligent charging device;

step 300), the AGV vehicle sends a vehicle in-place signal to the intelligent charging device;

step 400), extending out a charging copper block 8 of a charging mechanism on the intelligent charging device;

step 500), the charging copper block 8 extends to the right position, and the charging mechanism sends out a signal that the charging copper block 8 is in the right position;

step 600, a BMS system of a battery in the AGV sends a charging permission signal, and a charging brush plate of the AGV attracts a charging copper block 8 on the intelligent charging device;

step 700, the intelligent charging device detects the battery voltage of the AGV, receives the charging requirement of a BMS system of the battery in the AGV, and outputs corresponding requirement data according to the instruction requirement of the AGV;

step 800), the intelligent charging device starts to charge the AGV;

step 900), the AGV vehicle reports an error and sends a charging stopping instruction or the battery is fully charged; the AGV vehicle error reporting comprises the steps that the surface temperature of the charging copper block (8) exceeds a limit value, the battery voltage of the AGV vehicle is abnormal, the charging copper block (8) is not in contact with a charging brush plate of the AGV vehicle or the contact is not in place, and the like. If the AGV vehicle reports errors because the surface temperature of the charging copper block exceeds the limit value and sends a charging stopping instruction, the charging copper block retracts, the step 300 is started again after the surface temperature of the charging copper block is recovered, and charging is continued until the battery is fully charged. If the other charging instructions are reported in error and sent out, manual intervention and maintenance are carried out in time, the step 300 is started again after the problem is corrected, and charging is continued until the battery is fully charged.

Step 1000), stopping charging by the intelligent charging device, and recovering the charging copper block 8;

step 1100), the AGV vehicle intelligent charging device starts to work.

The use method of the intelligent charging device is simple to operate, and the AGV can be safely and effectively charged.

The foregoing embodiments are merely illustrative of the principles and utilities of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Accordingly, it is intended that all equivalent modifications or changes which can be made by those skilled in the art without departing from the spirit and technical concepts disclosed herein be covered by the appended claims.