FR2648367A1 - Improved grinding machine (crusher) which automatically adapts to variable resistive loads - Google Patents

Abstract

Grinding machine 11 driven by a motor 12 and provided with a device adapting the speed to the force necessary for grinding. According to the invention, the machine includes one or two spindles 16 carrying grinding knives 17, the said spindles driven by a connecting rod/crank system 32-50 with interposition of a device 40 allowing the transmission ratio between the said motor and the said knife-carrying spindles to be varied automatically depending on the force necessary for grinding. Depending on the variants, the device 40 modifies either the radius r of gyration of the journal 39 driving the connecting rods, or the active diameter of the driving pulley 26.

Description

IMPROVED AUTOMATIC GRINDING MACHINE
VARIABLE RESISTANT EFFORTS.

This patent relates to a grinding machine
specially adapted to variable resistant forces
which allows with a motor of limited power to obtain
results close to those of much more machines
powerful. We have noticed that in the case of
crushing or shredding including waste
most of the time, the effort required remains
weak until a bone, a crate angle, a
metallic bot presents itself. Classic machines are
designed to be able to continuously exert effort
necessary. In the advanced machines object of
present patent, one makes so that 1 maximum effort does not
be developed only when necessary at the cost of a
correlative reduction in speed. This patent
describes in particular the mechanical devices which
allow the automatic adaptation of the engine torque to the
resistant couple.

The things produced according to the invention include
of; grinding knives carried by one or two axes in
generally al horizontal, the said knives are inserted between ies
fixed counter knives. The respective profiles of the said
knives and di t; counter knives are such that it
push materials to sew on to force them to
present in the sharp part. The-. d: ts carrier axes.
knives are I i és each to a manual par
1 intermediate of a unidirectional mechanical coupler
of the freewheel or anti-reverse type imposes on the said axes
one direction of rotation. The so-called manual are
each actuated by a link pushed by a pin
which is carried by a drive wheel. In the case of two
axes, so that one turns for half a turn
of the drive wheel while the other is stationary and
reciprocally
In a first device perfects, the teurillon
associated with the crank-twin system is carried by a
combination of two articulated links whose movement
relative is guided by a cam system allowing
to impose the law of uariation of the trunnion-axis distance
depending on the force, the spring can also
be replaced by a stack of so-called washers
"Belleville" whose choice allows to obtain a law not
linear stiffness as a function of compression.

In a second device, the pin associated with the
crank-rod system is guided so that it can be
move radially relative to the axis of the drive wheel,
the displacement is obtained by a screw-nut system associated with
a corner gear. A torque limiter is interposed between
the e motor and the said wheel motr i what rlor tells you
journal, the d: t motor cheerfully drives a wheel
secondary carried by the same axis as the driving wheel. The
said secondary wheel is linked to the screw of said system
screw-nut by a detachable device at the end of the race. The
transmission ratios are chosen so that in the absence
slip of said torque limiter, the secondary wheel
turns slightly faster than the drive wheel and the
vis moves the pin to the maximum radius.

In a third device, the pin is fixed on
the driving wheel but the motor carries an illey pulley
mobile which allows the traperoidal drive belt
of the said driving wheel to carry along a variable radius
of the said pulley as a function of the effort to be provided. A
neighboring device is well known for its use as
speed variator for. moped.

The invention will be better understood using the
following description of a grinder produced according to
the invention and three variants of the adapter device
of effort given as examples and attached drawings
that represent :
FIG. 1, a perspective view of a grinder.

Figure 2-, an elevational view of a first mode of
realization of the effort adapter
The figure ! an elevational view and Figure 4 a
side view in section, of a second embodiment ce
the effort adapter.

Figure 5, an elevational view of a third mode
of the effort adapter.

Figure 6, a side view in section of a pulley
expandable.

Referring to the drawings, a broxeur has been represented.
11 mainly consisting of an electric motor 12, a
hopper 14, of two receiving arcs l @@, 16b,
horizontal, carrying knives 17 and a mechanical
transmission 18, arranged between the shaft 19 of the motor 12 and the
two receiving trees l @. The hopper 14 is open to its
upper part and those trees are installed
also i have an a @ other to work this one, being
supported by bearings 20 fixed on those opposite walls
21 of the hopper 14. The knives 17 are conventionally in the form of double hooks @ lie overlap next to the
counter-knife edge 22 fixed on a support 24
defining a succession of channels. This support is
mounted at the bottom of the hopper, between the shafts 16,
parallel to these; the said support is fixed to the two
walls 21, between the bearings 20.

The transmission mechanism 18 includes: a pulley 23
of betit diemeter fixed to the end of the shaft 19 of the
motor '2. a belt 2 driving a driving wheel ci
a pin 39 linked to said drive wheel, and two connecting rods
32 connected to the receptor shafts the via
two cranks 50 and two drive mechanisms
unidirectional in rotation 24. The so-called mechanisms
of unidirectional rotation drive are
commercial products known as "liter-wheel"
or "anti-cévireur", they do not need to be described
as for their mode of realization. We also have
each of the trees has an elementary backstop
70 constitutes for example a spring wound on the said
shaft and one end of which is flexed to the bearing
correspondent 20.

Thus, each connecting rod 32 has a first end
@ é connected to the drive wheel @@ by the pin 35 and a
second e @ hopper 38 connected to a crank 50 by a
articulation 51. According to a characteristic of the invention.
the pin 39 on which the rods 33 are articulated.
linked to the driving wheel 30 per a dierce tif adapter
firmer drive variator this race 40 including two exemsies
of executives will be described more clearly. this device is arranged in such a way that the distance r between the axis of the pin 39 and the axis of the drive wheel 30 decreases when the reaction force exerted by a connecting rod 32 increases.

The operation of the mill thus described is as follows:
The motor 12 drives the driving wheel 30 in the direction of the arrow 100 by means of the belt 27; the pin 39 describes a circle of radius r around the axis 30a of the wheel 30s the connecting rods 32a and 32b are therefore alternately pulled then pushed; by their articulations 51, they drive the cranks 50a and 50b respectively, in an oscillation movement around the axes 16. the amplitude of said oscillation movement can be defined by the distance (approximately 2 @) which separates the extreme positions occupied by the joints 51. Said positions also define for each axis lo, an angle of rotation. It should be noted if the two cranks 50a and 50b have not
at the same length, the said angles of rotation will be
different for axes 16a and 16b. When a bee is pushed. the direction of assembly of the associated drive @ rectional in rotation 34, is such that 1 axis @@@@ es @ oncant if is driven: the knives 17 ground, da res c @ c @@ axis are active and push the materials to brew between the counter knives 22, when a bie'le. and consequently the associated crank, begins its movement of @ etr @@, ie mecan @ eme d @ entrainement unidirect onne @ en @@@ ation 3 @ ass @@@ e, ceati @ carise 'a maniue @ e 51 ze @ are @@ On eventue 'return trcvcdue by these tr@cu.te to trt / er d @ t presentent a certain elastic @ té suitable for retcuss ccuteaux 17, is prohibited tar the devices tife ant -dédireurs 70. The fixed point of the cites cispositife @ 0 is real @ easy to dismantle to allow cleaning of the machine by manual drive of the axes in reverse.

 It is necessary that the axes léa and 16b are successively active then immobile, allowing all the power drawn to concentrate on a single axis: this characteristic is also favorable to the stitching since it causes a movement of the materials which present themselves in front of the knives.

 In the event of an increase in effort, this will be explained later. the adapter device 40 brings the pin 39 closer to the axis 30a of the drive wheel 30. the amplitude of the movement of the rods 2 @, and consequently the amplitude of oscillation of the axes 16 decreases, proportionally increasing the force applied to the knives . When the force decreases, the adapter device 40 moves the pin 3c away from the axis 30a, the amplitude of movement of the rods 2 @ aucmente and the force available on the knives decreases until a further increase in the grinding effort.

2 shows an elevation of a first embodiment of the effort adapter device 40: there is shown at 30 the driving wheel carry 1 set of the mechanism, said wheel is driven in rotation in the sene arrow 100: at 41, a pi @ pt secured to the wheel 30: at 42, a pivotart tiellette around pivot 41: at 45, a taper supported by
1 end 101 of a guide pipe 102. free to wander
author of a pivot 103 solida @ re of the wheel 30.

Said spring 48 acts on the rod 42 by an anticulation 45 which the rod 102 crosses. A cam 104 is free to rotate about an axis 105 fixed to the rod 42
A stop 46. integral with the wheel 30, limits the movements of the link 42 and of the cam 104. Said cam 104 carries an il Ion turn 39 where the two connecting rods 32 of the mill 11 described in the first part are articulated of this patent.

Two rollers 106 and 107 fixed on the wheel 30 cooperate with the cam 104 to impose a path 108 on the pin 39 when the resistant force transmitted by the connecting rods 32 varies. The path 108 is understood by reference to the wheel 30
In the absence of a resistant force, the spring 48. pushes the link 42 upward, in the direction. the mechanism is represented on the figu @ e. Pressed on the roller 106, the cam pivots around the axis 105 and the pin 3? is located at the end 108a of its trajectory 108.

The distance r between the pin 39 and the axis 30a of the wheel 30 is maximum.

 When a sufficient force is present on the rod 32b, the cam 104 bears on the roller 106 and drives down the figure the rod 42 which compresses the spring 48. The pin 39 follows its path 108 and the distance r decreases, which increases the force transmitted to the connecting rod 32b.

 The wheel 30 being in rotation. the angle of incidence of the connecting rod 32b varies and, to respect the trajectory 108 in all angles of incidence. the cam 104 comes to rest on the pallet set 107. which allows reaching the end 108 t of the path @ e 108 of the pin 32.

 When the resisting force decreases, the spring 48 relaxes, pushes the link 42, causing the cam 104 to rotate, the pin 3 @ pushes the link 32b and the distance @ increases.

 We can use the same exollcation with the bielde 32a when the wheel 30 has turned half a turn by contribution to the position shown in FIG. 2.

The cama's profile is determined from the chosen path 108 by graphic sketching using a traditional method or by computer assisted calculation.

In an embodiment which has proved effective in practice, a cam profile has been chosen which produces a trajectory 108 in the form of a spiral where the energy received by the wheel 'O is shared equally between that stored by the spring 48 and that transmitted to the connecting rod 32b. Ceti is facilitated by using a spring with nonlinear characteristic consisting of a stack of washers - springs called "Belleville 'assembled according to the directives provided by the manufacturers of the said washers - springs.

 When the connecting rods 32a and 32b are very short, there are limit conditions of force and angle of incidence where the cam 104 can leave the support of the gays eta 106 or 107. It is then advisable to have on the cam 104, near the pin 39, a finger which cooperates with a cam follower secured to the wheel 30 to prevent the loss of contact between the cama 104 and at least one of the rollers 10 @ or 107. four more clear, said finger and said cam follower have not been shown in the figure.

The position of said finger and the profile of said countermeasure are determined in this way in a graobic way or by computer-assisted calculation.

 To limit the cantilever as much as possible, the link 42 can be doubled with an identical link located at the ring of the wheel disc 30 by extending the pivot 41, the articulation 45, and the axis 105 and by sparing lights for the movement of these elements.

 In a simplified embodiment, reserved for low powers, the cam 104 is reduced to a connecting rod which pivots around the axis 105 and which carries at its other end the pin 39. The guidance is obtained by a finger extending the pin 39, the said finger moves in a groove made in the wheel 30 along the path 108.

 This mechanism, even produced with reduced play, is relatively noisy when the spring 48 relaxes following an abrupt reduction in the resistance force. This is remedied by adding a single acting shock absorber which allows free compression of the spring but which slows down its relaxation.

Said shock absorber is for example of the telescopic hydraulic type and is fixed parallel to the spring 48. It is even possible to combine the spring and the shock absorber in a hydro-pneumatic assembly similar to certain shock absorbers used in automobile construction.

 This device has the advantage of permanent adaptation to the nearest half-turn, from speed to available power at the cost of a certain complexity of construction.

It makes it possible to exceed a ratio 5 between the extreme speeds.

FIG. 3 represents an elevation view and FIG. 4 a sectional profile view of a second embodiment of the force adapter device 40:
The drive motor of the machine is shown at 12, the axis 19 of which carries two pulleys: the main pulley 26 lite to the axis 19 by a torque limiter 72 drives by a belt 27, the drive wheel 30 in the direction of sheet 100; the secondary pulley 12o linked directly to the axis 19 of the motor 12 driven by a belt 127 a secondary wheel 130 linked to the bevel torque 131 composed of the pinion 131a secured to the secondary wheel 130 and the pinion 131b 1 tee by a disengageable cutter 132 to a screw 133 disposed radially on the wheel 30. The disengageable coupler 132 is for example of the well-known type which equips the so-called "ratchet" screwdrivers, so there is no need to be described. In the present case, the cursor which makes it possible to choose the blocking or a determined direction of drive is replaced by a ring 132a returned to the blocking position by a spring.

The screw 133 is immobilized in translation by its bearings 134 and 135 secured to the wheel 30. On the screw 133 is a nut 144 which moves in a slide 140 secured to the wheel 30, the said nut is immobilized in rotation by guide shoes 145. A sliding rod 146 connects the ring 132a to the nut 144 when the said nut 144 approaches its position 144a furthest from the axis of your wheel 30. The nut 144 also carries the pin 39 whose l 'axis is parallel to the axis of the wheel 30. On the pin 39 are articulated the two connecting rods 32 of the crusher mechanism described in the first part of this patent. The distance r between the axis of the wheel 30 and the axis of the pin 39 represents, as before, the crank reason for the device for driving the connecting rods.

The tensioned arm 127a of the belt 127 optionally comprises a tensioner 128 which acts on an automatic stop contact of 1 machine in the event of blockage.

The explanation of the operation assumes five cases:
1- The nut 144 is assumed at the start at an intermediate point of the screw 133 and a resistive torque lower than that which causes the sliding of the torque limiter 72.

The transmission ratios between the pulley 27 and the wheel 30 on the one hand and between the pulley 127 and the secondary wheel 130 on the other hand, are such that the secondary wheel 130 rotates less quickly than the wheel 30. By reference to said wheel 30, the secondary wheel 130 therefore rotates in the direction opposite to the arrow 100. The screw 133 rotates slowly in the direction which moves the nut 144 away from the axis of the wheel 30; the distance r increases, the stroke of the connecting rods 32 increases and the available force decreases proportionally. When the nut 144 approaches its position 144a, it pulls the rod 146 which acts on the ring 132a of the declutching coupler 132 and the screw 133 comes to a standstill as does the nut 144.

 2- The distance @ being maximum, the grinding speed is maximum and, with constant resistant force, the amount required from the motor is maximum.

 3- When the torque requested from the engine increases beyond the regie of the limiter 72, the route 30 slows down. As the secondary wheel 130 remains driven at the same speed, with reference to the cited wheel 30. the secondary wheel 130 rotates in the direction of the arrow 100. The coupler 132 detracts in the opposite direction to the previous case, causes the screw 133 in the direction which brings back the er @ or 144 from the center of the wheel 20. the diatance @ decreases and. to effort resist @onetant. the torque p @ stant tr @@@ put by the courrc e 27 decreases proportionally jus @@ at the moment when 11 becomes less than the re-clutch torque of the torque limiter 72. The system is found al @ r @ in case 1.

4- In the case @@ treme where the resistant couple is such
or @ i @ blocks the wheel 30. the operation is the same due in case 3. but the screw 135 turns faster and the distance @ decreases more rapidly until the moment when the resistant torque transmitted by the belt 27 allows re-engagement of the torque limiter 72.

 5- If the nut 144 reaches the stop position 144b where the distance @ is minimum without the resistive torque transmitted by the belt 27 having become below the re-clutch torque of the torque limiter 72, the belt 127 is solilcitated more strongly this which reacts on the tensioner 129.

Said tensioner 128 is adjusted to stop the machine in this circumstance where the cabacity of the crusher has been exceeded.

A manual cleaning operation will restart
This device, less efficient than that described previously with regard to the adaptation of the speed to the available power, since it takes several turns of the drive wheel to reach the optimum, has the advantage of a quieter operation. Like the previous one, this device makes it possible to exceed a ratio 5 between the speeds e @ tremes @ the limit is imposed by the games @, in part @@ ulie @ that of the drive mechanisms ur @@ @ sectionnel 34.

 FIG. 5 represents an elevation view of a third embodiment of the effort adapter device and FIG. 6, an expandable pulley with movable flanges, the upper half represents the pulley in tight flanged section, and the lower half, a side view + lasques removed.

12 shows the electric motor for driving the machine. The shaft 19 of said motor 12 carries a pulley for V-belt 26a, the flanges 74 and 75 of which can deviate from one another. A spring 76 pushes the said flanges in the direction of their approximation. Such pulleys are products
common industrialists whose detailed description is useless. A trapezoidal belt 27 ensures the transmission of the driving torque to the driving wheel 30 in the direction of the arrow 100. A spring tensioning device oS of known industrial type is placed on the return strand 2-b of the belt 27, it ensures permanently at the belt di 2 a maximum winding angle. The drive wheel 30 carries a fixed pin 39 where the two connecting rods 32 of the breaker 11 described in the first part of this patent are articulated.

Operation is expressed as follows:
As long as the resistive torque transmitted by the connecting rods 32 to the driving wheel 30 and then by the belt 27 to the pulley 26 @ remains lower than a uaieur cui cepend of the adjustment of the spring 76, the flanges 74 and 75 remain tightened to the maximum.

The belt 27 carries, as a function of its width over the smallest diameter, that the pulley @oa: the size of the wheel 30 is maximum.

 When the resistive torque increases, the tension of the stretched trin 27a of the belt 27 increases correspondingly and forces the flanges 74 and 75 to spread the belt 27 then has a smaller diameter than the pulley 20a, which increases the ratio this reduction of the transmission between the motor, 12 and the wheel 30. The speed of said wheel 30 decreases and the available cut increases proportionally.

When the resistant torque decreases. the tension of the stretched strand 27a of the belt @ 27 decreases which allows the flanges 74 and 75 to reboot and the system is found in the initial case.

 Such a device has the advantage of simplicity but it is limited to a ratio of approx @ ron 3 between the maximum and minimum speeds and to reduced p @@ ssances.

It also requires a slow motor, therefore expensive and bulky, or a speed reducer with two stages in order to obtain the speed range of the wheel 30.

Claims (17)

 1. Improved grinding machine characterized by the use of rotary knives (17) cooperating with fixed counter knives (22), said knives driven by a crank-rod system with the interposition of a unidirectional coupler (34? Imposing the rotation of the shaft (16) carrying the said knives in one direction and a device (40) automatically adapting the stroke or the speed of the said rod to the force supported by the said knives.  2. Machine according to claim I comprising two parallel axes carrying knives and two opposite connecting rods causing an alternating rotation of said axes carrying knives.  3. Machine according to claims i or 2 in which the transmission ratio between the engine and the drive wheel of the crank-connecting rod system varies automatically as a function of the force transmitted by said connecting rods.  4. Machine according to claim 3 wherein the var i at i or of the transmission ratio is obtained by an expandable pulley with motile flanges (26a) cooperating with a trapezoidal belt so that said belt carries a variable ravon of said pulley .  5. Machine according to claims 1 or 2 wherein the pin connected to the connecting rods is carried by a drive wheel with the interposition of a force adapter device (4 @) varying the ravon this rotation of said pin according to the force transmitted by said connecting rods.  6. Machine according to claim 5 comprising a force adapter device characterized by a driving hoe (30) carrying an anticulated link (42) and a pivoting cam (104) which carries the pin (39) for driving the connecting rods and a spring return device, all cooperating so that the crank radius (@) automatically adapts to the resistant force transmitted by the connecting rods.  7. Machine according to claim in which the pivoting cam (104) is supported successively on several guide rollers (106-107).  8. Machine according to; Claims 6 or 7 in which the profile of the cam (104) is determined so that the motive energy is shared by + a substantially equal amount between that ut 1 located to compress the spring (48) of the return device and that transmitted to the acti connecting rod (32t)  9. Machine according to claims 6 to 9 further comprising a finger carried by the cam (104) and a cam follower secured to the drive wheel (30) imposing on the d; cam (104) a permanent support on at least one of the associated rollers (106-107).  10. Machine according to claims 6 to 9 wherein the articulated link (42) consists of two identical elements located on either side of the mechanism for ensuring a better rigidity t of the axes and p i vot s  11. Machine according to claims 6 or 8 wherein the @uidage by cam is replaced by a finger moving in a groove formed in the drive wheel.  12. Machine according to claims 6 to 11 wherein the return spring (48) consists of a stack of spring washers called "Belleville".  13. Machine according to claims 6 to 12 further comprising a damper limiting the speed of relaxation of the spring.  14. Machine according to claim 5 wherein the drive wheel carries a screw-nut system (133 - 144) arranged radially, the said nut (144) carrying the pin (39) for driving the connecting rods (32), and a wheel secondary (130) driven in the same direction as the driving wheel, said secondary wheel (130) linked to said screw (133) by a bevel gear (131). The motor driving said driving wheel (30) by means of a torque limiter (72) and the transmission ratios being such that said nut (144) is driven slowly towards the outside of the driving wheel (30 ) if the torque limiter (72) does not slip.  15. Machine according to claim 14 wherein the radial guide of the nut (144) is a groove formed in the drive wheel (30).  16. Machine according to claims 14 to 15 wherein the connection between the secondary wheel (130) and the screw (133) comprises a blidirectional coupler (132) disengageable in only one direction of rotation by the thrust of the nut C144 > at the end of the race.  17. Machine according to claims 14 to 16 wherein the connection between the motor and the secondary wheel comprises a force limiter (128) causing the automatic stop of the machine in the event of excessive overload.