RU2108272C1 - Vacuum packing machine - Google Patents

Abstract

FIELD: packing of small-size articles in hermetically sealed film bags under special conditions of air or gas atmosphere by welding under vacuum in chamber or in chamber filled with shielding medium. SUBSTANCE: vacuum packing machine has two working chambers made en-bloc in one housing. Valve units and welding units of working chambers are coupled with common control unit through switching device connected with cover closed position converter of each chamber. EFFECT: increased efficiency owing to combining preparatory operations with main operation of machine. 3 dwg

Description

 The invention relates to devices for packaging products in sealed film bags under special conditions of air or gas environment and can be used to protect products during long-term storage from mechanical damage, exposure to atmospheric moisture, dust and gases by sealing by welding or filling, followed by sealing the bags in chambers under vacuum or containing an inert medium.

 A variety of vacuum packaging machines are widely mastered in industrial production, containing a working chamber communicating with a vacuum system, closed by a hinged lid, a movable beam of a welding unit with heating elements, and a mating support [1].

 In the said invention, the hinged lid of the working chamber is equipped with an autonomous vertical displacement drive and is mounted on guide columns, which ensures uniform pressing of the film material during welding with the required effort. The feed drive of the spring-loaded welding beam to the support with electric heating elements is made in the form of a cylinder fixed to the bottom of the chamber, communicating through a valve block with a vacuum system.

 The disadvantage of this machine is the cumbersome design, the complexity of setting up a sequential-action cycle control system for actuators and assemblies, in particular, feeding the lid, closing welding jaws, evacuation, and limited productivity, which narrows the area of use due to unsatisfactory functional reliability.

 The noted drawbacks are eliminated in the device for vacuum packaging of products into a film [2], containing a working chamber with a hinged lid, the plane of the connector of which is made inclined to ensure parallel closure and tightness while welding unit, control units and valves of the vacuum system. A support frame is fixed on the hinged lid, mating in the working position with a movable plate carrying heating elements of the welding unit. The plate is mounted on an elastic diaphragm of the working chamber, communicating through a valve block with a vacuum pump.

 A disadvantage of the known device is the limitation of productivity with a relatively large auxiliary time of manual operations for packing a package with products, switching modes and removal of finished packaging, which is 30.. . 35% of the cycle time or half of the main welding time.

 In addition, the kinematic relationship of the lid with the working chamber does not provide satisfactory quality for vacuum welding of critical packages due to uneven closure of the elements of the weld assembly, which depends on the elasticity of the diaphragm with a limited specific load limit.

 The technical problem to which the present invention is directed is to increase productivity with guaranteed quality of work and automate the management of the sequence of operations of the machine’s working cycle while reducing its consumer value.

 The required technical result is achieved in that in a known vacuum-packing machine containing a working chamber, the welding unit and valve block of which are connected to the control unit and closed by a hinged lid supporting the bearing, mating with the electric heating elements of the beam of the welding unit, freely mounted on the current-carrying supply rods cylinders, and a vacuum pump, according to the invention, the control unit is in parallel connected with valve blocks and welding units of two working chambers interlocked in a common housing through a commutator The present device, which is connected to transducers closed position covers the working chambers.

 Distinctive features made it possible to obtain a two-chamber unit of parallel-sequential action, in which auxiliary-prepared time was cross-combined with machines, and subjectivity of operators in process control was eliminated by installing transducers under each cover that generate control signals for switching the sequence of operation of the machine’s vacuum chambers and the sequence of operations of their executive units and mechanisms.

 The housing common for both working chambers of the machine, the instrument control unit, vacuum and power supply systems simplified the design, which increased the overall reliability of the unit.

 The invention as a stable set of essential features is a new machine, which is a quarter cheaper than two of the prototype, but with a productivity one third higher. The service area of the machine by one operator during aggregation was reduced by about half.

 In FIG. 1 shows a view of the proposed machine; in FIG. 2 is a view along arrow A in FIG. one; in FIG. 3 is a block diagram of a machine.

 Two working chambers 2 (Fig. 2 and 3) of a similar design and structural composition with a common control unit 3, a power supply unit 4 and a vacuum pump 5 (Fig. 1) are fixed in a common housing 1. An end cap 6 is supported on the housing 1 by an end face above each chamber 2, which are connected by means of brackets 7 to the springs 8, which are adjustable by means of cruelty nuts 9 mounted on the housing 1. On the covers 6 are fixed elastic support strips 10 of the welding units.

 The vacuum pump 5 communicates through valve blocks 11 with working chambers 2 (Fig. 3) and with feed cylinders 12 installed in each of them.

 On the rods 13 of the supply cylinders 12, made current-carrying and connected with the power supply unit 4, a beam 14 of the welding unit 15 is freely mounted, on the contact surface of which are fixed heating elements 16 (nichrome strip and wire), electrically connected to the rods 13, loaded with springs 17.

 The cavity of the cylinders 12 is covered by a membrane 18, which is pinched on the rod 13, dividing it into two parts: the upper one, connected with the valve block 11 of the pump 5, and the lower one, which communicates with the atmosphere. In the chamber 2, replaceable shelves 19 are laid under the processed product bag, opposite which rotary nozzles 20 for gas inlet of a protective or neutral atmosphere are installed behind the beam 14.

 Converters 21 (limit switches) are mounted on the connector line of the housing 1 with the cover 6 of each chamber 2 (Fig. 3), connected to the switching unit 22, which is connected to the welding unit and valve block 11 of each chamber 2 through a common control unit 3.

 In the initial position, the rod 13 of the cylinders 12 is de-energized and pressed downwards by the action of the springs 17, and the chambers 2 are opened, that is, the covers 6 are turned by the rocker to the highest position (Fig. 1 and 2, the right half according to the drawing).

 Rotation of the nuts 9 in different directions controls the stiffness of the springs 8, ensuring uniform pressure on the cover 6 with the end face (pivot axis) to the surface of the housing 1, which creates a clearance-free closing in the closed operating position.

 The machine operates as follows. When you press the "Start" button on the remote control unit 3, the pump 5 and the power supply unit 4, which connects the heaters 16 through the rod 13.

 The product in a bag of multilayer polyethylene is stacked on shelves 19, the maximum number of which is selected to reduce the free volume of the chamber 2. The neck of the bag is put on the nozzles 20 by spacing due to their rotation, after which the cover 6 is manually lowered until it closes with the housing 1, stretching the springs 8 (Fig. 2, left half), the elastic deformation of which is a temporary accumulation of energy. In this case, the cover 6 interacts with the converter 21, the signal from which passes through the switching unit 22 to the control unit 3, which generates an identified channel start command that commutes the corresponding welding unit 15 and valve block 11, and a random signal from the converter 21 of the second chamber 2 is blocked in switch 22, that is, two channels simultaneously cannot work.

 Pump 5 through the valve block 11 creates a vacuum in the working chamber 2, while atmospheric pressure covers 6 tightly pressed against the housing 1 and, if necessary, a portion of the protective or neutral gas is injected into the bag.

 Then, by switching the valves of the block 11 to the pump 5, the upper part of the cavity of the cylinder 12 above the membrane 18 is connected, where a vacuum is created. Atmospheric pressure of the lower cavity of the cylinder 12, the rod 13, compressing the spring 17, feeds the beam 14 to the stop by the elements 16 into the strip 10 of the cover 6, where they self-tightly self-install by hinging the beam 14 with the rod 13.

 With the heated elements 16, the package with the product is sealed with a double weld: the film is welded flat, and the wire of larger diameter is cut with the material being melted.

 Then, the switch 22 by means of a control signal from the block 3 switches the valves of the block 11, as a result of which the pressure in the cavities of the cylinder 12 and in the chamber 2 is aligned with atmospheric. Under the action of the energy of the spring 17, the rod 13 returns the beam 14 to the lower position, and the springs 8 - the cover 6 is rotated, allowing access to the chamber 2. In this case, the signal from the converter 21 will reconnect the communication line 3 with the block 22 to its original position.

 Next, close the lid 6 of the second chamber 2, where the next package with the product has been previously laid, and the cycle is mirrored.

 The finished sealed bag is removed from the first chamber 2 and in its place during welding in the adjacent chamber 2 the next packet is laid, the neck of which is put on the nozzles 20.

 Thus, in time, the auxiliary operations are combined with the main ones, the duration of which (30 s) is twice the duration of the first (14 s), therefore, the productivity of the unit is determined by machine time, that is, practically the technological time of welding.

 The work cycle, duration and sequence of operations allow serving the proposed machine to one operator.

 The structural autonomy of the working chambers and electric channels for controlling the cycle of work allows expanding the technological capabilities of the machine, in which bags of various shapes and materials can be sealed at the same time, packaging different products under vacuum and with filling, using combinations of welding seams by changing heating elements.

Claims (1)

 A vacuum-packing machine containing a working chamber, the welding unit and valve block of which are connected to the control unit and closed by a hinged lid, bearing support, mating with the electric heating elements of the beam of the welding unit, freely mounted on the current-carrying rods of the supply cylinders, and a vacuum pump, characterized in that the control unit is in parallel connected with valve blocks and welding units of two working chambers interlocked in the common housing through a switching device that is connected to the converters of the closed provisions of covers of working chambers.

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