SK279983B6 - Perching machine with multiple beating plates for processing industrial hides - Google Patents

Abstract

A perching machine (1) with multiple beating plates (6', 6'') for softening and stretching industrial hides and the like including conveyor belts (3, 4) for advancing the hides between a plurality of upper beating plates (6, 6'') which face an equal number of lower beating plates (7', 7'') adapted to form adjacent pairs in the hide advancement direction. Each pair of facing plates includes a movable plate and a fixed plate. Motors (M', M'') alternatively move each movable plate toward and away from the respective fixed plate. Synchronization pulleys (21', 21'') are provided which act on the motors in order to equalize the oscillation frequencies of the adjacent movable plates.

Description

Technical field

BACKGROUND OF THE INVENTION The present invention relates to a drawing machine with a plurality of softening plates and the drawing of industrial skins and the like, comprising a support frame on which a skin carrier is mounted, a plurality of upper plates and lower plates, facing each other and arranged opposite each other. a pair of milling plates distributed along the skin conveyor track, each of the milling plates being provided with projections adapted to cooperate with complementary recesses formed on the respective opposing rolling plate, each pair of mutually opposed plates being formed by a movable plate and a fixed plate and the movable plates being coupled with a motor drive for controlling the movement of the movable plates alternately towards and away from the fixed plate, the motor drive comprising at least one electric motor coupled to a crank mechanism for transforming a rotor Joint motion motor into an oscillating motion of the movable plates, formed in each movable plate main shaft connecting the rods and crank.

BACKGROUND OF THE INVENTION

Machines of this type serve to stretch the skin fibers during the stretch process, which is used to restore the softness and flexibility of the skins after drying.

IT-PS 883 012 discloses a drawing machine comprising a pair of fulling plates. In order to increase the capacity and productivity of this known drawing machine, a machine with a plurality of tiling plates arranged one behind the other in the direction of travel of the skins was later used. Each of the kick plates was controlled by a separate electric motor to reduce the power and weight of the installed electric motors.

Broaching machines of this type are particularly advantageous in that they have substantially improved function and productivity, but also have some disadvantages and are associated with some problems. Although the electric motors used to control the operation of each caliper plate are identical, their rotational speed varies as much as the maximum power delivered and it is therefore not possible to ensure exactly the same frequency of movement of the individual plates. In addition, due to the oscillating movement of the plates, the machine support frame as a whole is exposed to significant vibrations, which are only partially compensated by eccentric values and weights and damping the bearing of the moving parts. As there are differences in the frequency of the oscillating movements, the plates tend to gradually lose the synchronization of their movements until they gradually enter the same phase, even though they are initially set to phase opposition. The drawing machine is thus repeatedly exposed to resonant highs, accompanied by high shocks and noise.

These resonances can lead to damage to the supporting and supporting structure of the machine, especially in welded joints, over a period of time, which substantially shortens the average life of such machines and makes it necessary to repair and interrupt the operation of the machine.

Another disadvantageous consequence of these resonance phenomena is to limit the maximum oscillation frequency of the kick plates to values of about 550 to 570 kick movements per minute in order to avoid dangerous vibrations in the drawing machine design.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to overcome the problems and drawbacks described and to provide a drawing machine structure with a plurality of milling plates which is sufficiently reliable and ensures high productivity while maintaining quiet operation and uniform operation.

It is a further object of the invention to provide such a drawing machine structure which is provided with a plurality of milling plates, wherein their operation prevents the occurrence of resonance phenomena caused by the oscillating movement of the milling plates.

It is another object of the present invention to provide a drawing machine structure which comprises a plurality of tufting plates arranged so that the machine can operate at a higher frequency of these oscillating movements than in the prior art machines without causing resonance phenomena.

SUMMARY OF THE INVENTION

These objects are solved by a drawing machine according to the invention, provided with a group of cushions for processing industrial leathers and comprising a support frame on which a leather transporting device is mounted, a group of upper cushions and lower cushions facing each other and arranged in mutually opposite pairs cushioning plates disposed along the skin conveyor path, each of the cushioning plates being provided with projections adapted to cooperate with complementary recesses formed on the respective opposing cushioning plate, each pair of mutually opposing plates being formed by a movable plate and a fixed plate and the movable plates being coupled with a motor drive for controlling the movement of the movable plates alternately towards and away from the fixed plate, the motor drive comprising at least one electric motor coupled to a crank mechanism for converting rotationally motor for oscillating movement of the movable plates, formed for each movable plate by a main shaft, connecting rods and a crank. SUMMARY OF THE INVENTION The motor drive is provided with a synchronization device for equalizing the oscillation frequency of the movable plates comprising transmission elements interposed between the main shaft of each pair of full plates and the main shaft of an adjacent pair of full plates and adapted to maintain alternating movement of each movable plate. the opposite phase.

In a preferred embodiment of the invention, the transmission element has a 1: 1 ratio and all transmission elements are adjusted to maintain a 180 ° angular rotation of the keys of all adjacent main shafts. In a particular preferred embodiment of the invention, the transmission elements comprise a pair of toothed pulleys which are wedged on adjacent main shafts and which are interconnected by a toothed belt. Alternatively, the motion transmission elements are selected from the group of transmission devices including rigid gear shafts with pairs of end gears, cardan or similar gear shafts, electronic speed controllers and the like. Each movable cushion plate is coupled to a respective separate electric motor, or all movable cushion plates are coupled to a single common motor.

In practical use, it has been observed that the drawing machine according to the invention fully achieves the intended effects and fulfills the intended task, and in particular eliminates the resonance phenomena which have been typical of previously known and used drawing machines with a number of full plates. It has also been observed that the broaching machine of the present invention is capable of operating at a higher speed, at a frequency of about 650 beats per minute, which increases production productivity by about 20% so that no resonance phenomena occur.

Further features and advantages of the broaching machine according to the invention are illustrated in more detail in specific embodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be elucidated in more detail by means of the exemplary embodiments shown in the drawings, in which:

Fig. 1 shows a longitudinal section through a drawing machine according to a first exemplary embodiment of the invention, FIG. 2 is a side view of a detail of the synchronizing device of the drawing machine shown in FIG. 1 shows a dotted line, and FIG. 3 is a side view of another exemplary embodiment of the detail of FIG. Second

DETAILED DESCRIPTION OF THE INVENTION

The drawing machine 1 according to the invention shown in the exemplary embodiment of FIG. 1, it comprises a support frame 2, which is made of solid steel beams and supports a skin shifting device P formed by a pair of conveyor belts 3, 4 having abutting parts placed in contact with each other to ensure that the skin P having be processed.

On the opposing sides of the conveyor belts 3, 4 facing away from the abutting surfaces of these conveyor belts 3, 4, pairs of punching plates 5 are disposed; In the illustrated exemplary embodiment, two pairs of cushion plates 5 ', 5' are shown, but their number can be increased according to specific requirements in order to increase the productivity of the drawing machine 1 according to the invention. Each pair of cushions 5 ', 5' is formed by an upper plate 6 and a lower plate 7, which are located on mutually opposite sides of the treated leather P. The first pair of cushions 5 'is formed by a first upper plate 6' against which The first lower plate 7 'is positioned on the skin P, while the second pair of cushions 5 "is formed by a second upper plate 6", against which the second lower plate 7 "is placed down.

Similar to the known drawing machines of this type, the upper plates 6 ', 6 "are suspended by means of suspension arms 8', 8" on the supports 9 ', 9 ", which are mounted on the support frame 2. The upper plates 6', 6" are further provided with protrusions 10 ', 10 "which cooperate with complementary recesses 11', 11" formed in the bottom plates 7 ', 7 ".

The movable upper plates 6 ', 6 "are coupled to a motor drive which sets them in oscillatory motion at a selected amplitude and frequency around the center 9', 9" of rotation to induce their alternate approaching and moving away from the fixed lower plates 7 ', 7 ". ”To provide alternate engagement and disengagement between the protrusions 10 ', 10” and the recesses 11', 11 ”. The motor drive may be formed by connecting rods 12 ', 12' which connect the pivot pins 13 ', 13' with the cranks 14 ', 14'. The pivot pins 13 ', 13' are fixed to the movable top plates 6 ', 6' and the cranks 14 ', 14' are fixed to the respective main shafts 15 ', 15'. The main shafts 15 ', 15' are rotatably mounted in the support frame 2 and are rotated by respective electric motors M ', M' by means of modified transmission drive belts 16 ', 16'.

In order to achieve a uniform effect of the drawing machine 1 according to the invention during the working operation, its flywheels 17 ', 17 "are fixed to each main shaft 15", 15 "and are provided with an eccentric weight 18", 18 ". The flywheels 17 ', 17' may advantageously be provided with lightening holes 19 ', 19' which are designed to perfectly balance the movement of the upper plates 6 ', 6' and at least partially reduce the vibrations of the drawing machine 1.

In a preferred embodiment of the invention, the broaching machine 1 is provided with a synchronizing device 20 which acts on the motor drive to equalize the oscillating frequency of the two adjacent upper plates 6 ', 6'.

In FIG. 2 shows a first exemplary embodiment of this synchronization device 20, comprising pairs of toothed rollers 21 ', 21 ", which are keyed on the main shafts 15', 15" and connected to each other by an adapted toothed belt 22. The synchronizing device 20 is preferably supplemented with a tensioner pulley. 23 so that the toothed belt 22 is always tensioned. The toothed pulleys 21 ', 21 ”have the same diameter and the same number of teeth, so that the transmission ratio between the two main shafts 15', 15” is 1: 1. Again, it is recalled that the toothed pulleys 21 ', 21 ”are angled on the main 15 ', 15 ”shafts to keep the 14', 14” cranks in phase opposition.

In the second exemplary embodiment of the synchronizing device 20 shown in FIG. 3, the transmission element is a transmission shaft 24 on which the end gear wheels 25 ', 25' are keyed. These end gears 25 ', 25' are engaged with bevel gears 26 ', 26', which are firmly attached to the main shafts 15 ', 15'. Also, in this case, the gear ratio 1: 1 and the cranks 14 ', 14' are positioned exactly in phase opposition.

It is of course also possible to use other synchronization devices 20 ', indicated by the dotted lines in the left part of FIG. 1, which are also intended to equalize the rotational speed at the third top plate 6 '' shown in FIG. 1 with dashed lines.

In operation of the broaching machine 1 according to the invention, the rotational speed of the main shafts 15 ', 15 "and possibly of each other main shaft is kept at exactly the same values, the cranks 14', 14" being oriented to maintain oscillations of the upper plates 6 ', 6 ”In phase opposition during the entire operation of the broaching machine 1.

The drawing machine 1 thus formed can be further varied by a number of modifications and variations of the construction which fall within the scope of the claims. Thus, for example, the transmission elements in the synchronization device 20 may be replaced by technical equivalents, for example by universal joints and universal clutches, or by a hydraulic or electrical transmission system having the features of any of the claims. Instead of a plurality of drive motors M ', M' coupled to the respective main shafts 15 ', 15', a single engine can be used, coupled to all the main shafts by means of suitable transmission and transmission devices.

If the technical features of the broaching machine 1 referred to in the claims are supplemented by reference numerals, these reference numerals are merely intended to increase the clarity of the claims and at the same time have no restrictive effect on the scope of each claim,

The markings only relate to exemplary embodiments of broaching machine components 1.

Claims (7)

PATENT CLAIMS 1. Broaching machine with a group of fulling plates for the processing of industrial leathers and similar materials, comprising a support frame on which a leather transporting device is mounted, a group of upper fulling plates and lower fulling plates facing each other and arranged in mutually opposite pairs of fulling plates spaced along the skin conveyor path, each of the tiling plates being provided with projections adapted to cooperate with complementary recesses formed on the respective counter-tiling plate, each pair of opposing plates being formed by a movable plate and a fixed plate, the movable plates being coupled to the motor a drive for controlling the movement of the movable plates alternately towards and away from the fixed plate, the motor drive comprising at least one electric motor coupled to a crank mechanism for converting the rotary motion of the motor to the melting movement of the movable plates formed by the main shaft, the coupling rods and the crank for each movable plate, characterized in that the motor drive is provided with a synchronization device (20) for equalizing the oscillation frequency of the movable plates (6 ', 6 ") comprising transmission elements; interposed between the main shaft (15 ') of each pair of fulling plates (6', 7 ') and the main shaft (15 ") of an adjacent pair of fulling plates (6', 7 ') and adapted to maintain the alternating movement of each movable plate (6', 6 ”) constant in the opposite phase. Broaching machine according to claim 1, characterized in that the transmission element has a transmission ratio of 1: 1. Broaching machine according to claim 1, characterized in that the transmission elements are adjusted to maintain the angular rotation of the keys (14 '', 14 ") of all adjacent main shafts (15 '', 15") by 180 ° Broaching machine according to claim 1, characterized in that the transmission elements comprise pairs of toothed rollers (21 ', 21 ") which are keyed on adjacent main shafts (15', 15") and which are interconnected by a toothed belt (22). . Broaching machine according to Claim 4, characterized in that the transmission elements for the movement transmission are selected from the group of transmission devices, comprising in particular rigid gear shafts (24) with pairs of end gears, cardan or similar gear shafts, electronic speed controllers. Broaching machine according to claim 1, characterized in that each movable cushioning plate (6 ', 6 ") is coupled with a respective separate electric motor (M', M '). Broaching machine according to claim 1, characterized in that each movable cushioning plate (6 ', 6 ") is coupled to a single common motor.