Method For Counting Sheets Of Paper And Apparatus

Abstract

A method and an apparatus for counting the numbers of piled up sheets of paper by means of a sensing device including a probe, wherein said probe runs, for scanning thereof, along a slanted slope defined by the side edge portions of piled up sheets of paper, each of which sheets is shifted a little aside from the lower one in succession for arrangement of their side edges in tiers, and oscillation of said probe, during scanning, is converted into an electric signal to achieve counting of numbers of sheets of paper thereby.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method for counting in a simplified way the numbers of piled up sheets of paper and an apparatus therefor.

2. Description of the Prior Art

To count the numbers of piled up sheets of paper, there has hitherto been used such a means either that the sheets of paper are taken out one by one from the piled stack for transport to a suitable counting device, or that the sheets of paper are turned over one by one by the human's hand for counting thereof.

In either instance, however, there has been a remarkable difficulty in counting the numbers of piled up sheets of paper with desired effectiveness. And this has been the noticeable disadvantage of the prior art.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a method for counting the numbers of piled up sheets of paper and an apparatus therefor, which are capable of counting the numbers of piled up sheets of paper with a good efficiency and which are free from such a disadvantage of inefficiency as possessed by the conventional method as well as the apparatus therefor.

Another object of the present invention is to provide a method for counting the numbers of piled up sheets of paper and an apparatus therefor, wherein the numbers of sheets of paper is counted in a simplified way but with exactness by means of a counting apparatus comprising a sensing device having a probe said probe is to be kept in contact with the sheets of paper in order to scan along a slanted slope defined by the side edge portions of sheets of paper. Each of the sheets is shifted a little aside from the lower one in succession for arrangement of the sheet side edge portions in tiers. Said probe is adapted to initiate oscillation every time it drops from one side edge portion of a sheet to that of the next lower one during scanning thereof. Every oscillation is converted into an electric signal, whereby the numbers of the sheets of paper is counted.

A further object of the present invention is to provide an apparatus, for counting the numbers of piled up sheets of paper, having a sensing device comprising a piezo electric element and a probe possessed of a spring effect. The piezo electric element and probe are disposed within the sensing device in such a manner that the piezo electric element is positioned in parallel with the probe with a predetermined interval therebetween and the top end the piezo electric element is connected with a portion of the probe through the intermediate of a cushion rubber. The base end portions of both the probe and the piezo electric element are fixedly connected to each other. A set of said probe and piezo electric element are supported by a supporting member at the fixing point where said base end portions connect and at a point on the probe just extended toward the top end thereof from the fixing point between a middle portion of the probe and the top end portion of the piezo electric element, through the intermediate of the supporting rubbers. The apparatus is capable of counting the numbers of piled up sheets of paper very exactly, the probe being adapted to make an accurate response to the arrangement in tiers of sheets of paper of very little thickness. Moreover, the apparatus is capable of manufacture at very low cost.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view showing a way of counting the numbers of piled up sheets of paper by means of an apparatus of the present invention, wherein a first preferred embodiment of sensing device is provided.

FIG. 2 is an enlarged front view of a sensing device included in the apparatus shown in FIG. 1.

FIG. 3 is a partially cross-sectional side view of the sensing device shown in FIG. 2.

FIG. 4 is a block diagram of an electronic counter of the counting apparatus shown in FIG. 1.

FIG. 5 is a view illustrating an electric circuit of the sensing device provided within the counting apparatus.

FIG. 6 is a view illustrating a waveform of the output from a piezo electric element.

FIG. 7 is a view for illustration of a waveform mode within a wave shaping circuit of the sensing device shown in FIG. 1.

FIG. 8A, 8B, and 8C are the views illustrating varied waveforms initiated in a wave shaping circuit of the sensing device shown in FIG. 1.

FIG. 9 is a partially sectional front view illustrating a second preferred embodiment of sensing device provided in a counting apparatus according to the present invention.

FIG. 10 is a fragmentary, partially cross-sectional front view on an enlarged scale of the sensing device shown in FIG. 9.

FIG. 11 is a left-end view of the portion of the sensing device shown in FIG. 10.

FIG. 12 is a cross-sectional front view of a piezo electric element portion of the sensing device shown in FIG. 10.

DETAILED DESCRIPTION OF THE INVENTION

In FIG. 1, reference character a denotes the sheets of paper piled up on a table c in such a manner that each sheet is shifted a little aside from the lower one in succession toward the foremost top of the stack, whereby all the side edge portions of the shifted-a-little-aside sheets of paper are arranged in tiers b and cooperate to form a slanted slope.

A first embodiment of a sensing device 1 of the present invention usable in counting the number of sheets of paper piled up as above-described.

Said sensing device 1 comprises a case 2 made of aluminium. A probe 3 of phosphor bronze is inserted into a small hole 5 defined in the foremost end portion of said case 2 and is held therein by an intermediate cushion rubber 4. The probe has an end portion thereof projected outwardly from said small hole 5. A crystal piezo electric element which is disposed within the expanded hole 6 of the case and is supported by supporting rubbers 7, 8. The piezo element is pressed toward said probe to result in contact between one end portion thereof and the rear end of said probe. A wave shaping circuit 10 is arranged within the cavity 11 of the case and has an electrical connection to the other end of said piezo electric element, a counting switch 13, and a clear switch 14.

The above-described sensing device 1 is connected to an electronic counter 25 through a lead line 12 connected with said wave shaping circuit at one end thereof.

Said electronic counter 25 is provided with a power switch 26, an one-round-count indicating window 27, a total-count indicating window 28, a clear switch 29, a foot switch 30, and a gate switch 31. Said foot switch can be used in place of said clear switch 29, since the foot switch is to function just the same as the clear switch does.

The electric circuit arranged within the electronic counter 25 is shown in FIG. 4, wherein the numerical references 15, 15' and 15" denote single place counters for the one-round counting. For instance the first counter counts the figure in the first place, a second one the figure in the second place, and a third one the figure in the third place, respectively.

The numerical references 16, 16', and 16" denote the respective decoders connected with said counters 15, 15' or 15". Each above-mentioned decoder is connected to an indicator tube 17, 17' and 17", respectively.

The numerical references 18, 18', 18" denote respective single place counters for the total count. For instance, the first counter is allotted to figures only in the first place, the second one to figures only in the second place, and the third one to figures only in the third place.

The numerical references 19, 19', 19", . . . denote respective a decoders connected to said counters 18, 18', 18" . . . individually. Each of said decoders is connected with an indicator tube, 20, 20', 20", . . . provided in the indicating window 28.

A numerical reference 21 denotes a timer, 22 denotes a gate circuit, 23 denotes a pulse generator, and 24 denotes AND gate circuit.

FIGS. 9 through 12 illustrate a second preferred embodiment of sensing device of the counting apparatus according to the present invention.

With provision of a second preferred embodiment of sensing device in place of the first one, the counting apparatus of the present invention can perform counting work in the same way as with the first preferred embodiment. Therefore, the following description is directed specifically to the second preferred embodiment of sensing device. Without repeating the above description of other parts of the counting apparatus.

The case 33 of the sensing device 32 is of bakelite, and in the outer, or sensing, end portion thereof, there is defined a contact plate 34 that is slanted to an imaginary, horizontal plane by 45.degree.-50.degree. and is provided with a slit 35 through which a probe 36 projects outwardly. The rear end of said probe is attached to a sensing member 37 as described later on.

The outer end portion of the probe 36 is bent downwardly and projects outwardly from said slit 35 sufficiently to scan along the tiers b of the slanted slope defined by side edge portions of sheets of paper a.

In addition, the outer, or foremost, end portion of the probe 36 is here of stainless material. When too narrow in its width and too pointed, it may not only harm the sheets of paper but may also be hampered in its effectiveness in scanning. Accordingly, it is desirable for the probe 36 to have thickness of 100 .mu. and width of 1 m/m in the outer end portion thereof. All other portions of the probe, except the outer end portion, are here of phosphor-bronze plate material, possessed of a spring effect (i.e. which is resilient) with thickness of 0.2 m/m and width of 2 m/m.

Said sensing member 37 includes a pipe 38 held within and fixedly attached to the case 33. Supporting rubbers 39, 40 are inserted into each end portion of the pipe 38. That is, said supporting rubber 40 supports the middle portion of the probe 36, while said supporting rubber 39 supports the base end portion thereof.

The positive side of the sensing member 37 is connected to a wave shaping circuit 51 and a preamplifier 42 through the intermediate of a contact member 41 disposed within the case 33, while the negative side thereof is connected directly to the case 33. The preamplifier 42 is connected with the line 12.

A numerical reference 43 denotes a piezo electric element disposed within said pipe 38 in parallel with the probe 36 at a predetermined interval. The base end portion of the piezo element 43 is fixedly connected to the base end portion of the probe 36 by means of soldering or bonding so that both base end portions are supported in turn by the pipe 38 through the intermediate of the supporting rubber 39.

Further, the outer end portion of said piezo electric element 43 is, within the pipe 38, fixed to a portion of the probe 36 through a cushion rubber 44, here of silicon rubber. The piezo electric element is here a ceramic bimorph.

As seen in FIG. 12, said piezo electric element 43 comprises a pair of ceramic plates 48, 49 coated with a damp-proofing paint 47 on the outer surface thereof, a reinforcement metal plate 50 held between said pair of ceramic plates, and output lines 45, 46 consisting of silver ribbon soldered to said ceramic plates.

OPERATION

To count the number of piled up sheets of paper with the aid of the first preferred embodiment of the present invention, at first the power switch 26, gate switch 31 and either the clear switch 29 or the foot switch 30 are turned on and all the indication tubes 17, 17', 17" as well as 20, 20', 20", are turned back to indicate a figure of 0.

Subsequently, as seen in FIG. 1, the outer, or foremost, end of the sensing device 1 is put onto the slanted slope defined by the side edge portions of the sheets of paper a piled up on the table c. The paper is so piled that each sheet is shifted a little aside from the lower one in succession for arrangement of said side edge portions in tiers c, so that the probe 36 of said sensing device comes in contact with the slanted slope to scan therealong at the scanning rate of 30 sheets per second.

Then the probe 3 initiates oscillation every time it drops from one side end portion of the sheet onto that of the next lower one. This oscillation of the probe effects a pressure toward the piezo electric element 9, whereby said piezo electric element generates an electric signal with such a A.C. waveform as shown in FIG. 6.

With regard to this waveform, it can be said that the period of oscillation in the initial phase remarkably differs from that in the final phase. This is because the period of oscillation in the initial phase is influenced mainly by the natural oscillation of piezo electric element itself. However, due to a rapid decrement thereof, the period of oscillation in the later phase depends only the oscillation of the probe itself, whereby there occurs a noticeable change with regard to the period of oscillation.

The thus resulted output is fed, without any modification, into a wave shaping circuit 10 (FIG. 5) as an input thereof. That is, the input is applied to the base of preamplifier transistor Q.sub.1, an emitter follower. Accordingly, the output waveform from the emitter follower Q.sub.1 has no negative values, as seen in FIG. 7. And then this output is transmitted to the base of transistor Q.sub.2 through resistance R.sub.3 and condenser C.sub.2.

Whenever no input is fed thereto, the collector potential of transistor Q.sub.2 stays always positive, as seen in FIG. 8A, but swings toward the negative when an input is applied thereto.

Upon this change of potential the base potential of transistor Q.sub.3 becomes biased toward the negative to so remarkable an extent that the collector voltage of transistor Q.sub.3 is changed into the negative values. Accordingly, the input is converted to a positive pulse, as seen in FIG. 8B, by passing through an integration circuit comprising resistance R.sub.11 and condenser C.sub.4. The latter pulse is fed into a monostable multivibrator comprising transistors Q.sub.4, Q.sub.5, and Q.sub.6, wherein is generated a positive output pulse with a width determined by the time constant of resistance R.sub.16 and condenser C.sub.5, as shown in FIG. 8C. Said positive output pulse is to have a sufficient width, or "on" time, to cover and thus invalidiate all the other oscillations initiated by any other causes in the system. The width of such positive output pulse, i.e. its on time should not be large enough to overlap the next output pulse to be generated as the probe drops down to the next tier of the sheet pile. The width of the positive output pulse should be determined, for instance, as to be 2 - 3 milli seconds.

Passing through the lead line 12, as shown in FIG. 1, the resulting output pulse is fed into the electronic counter 25, wherein digital counting is performed by the count circuit shown in FIG. 4.

When an one-round-count is required, indicator tubes 17, 17', 17" indicate figures on the one-round-count through the one-round-count indicating window. When the multi-rounds counts are required, a switch for the total count (not shown) should be turned on and then the indicator tubes for the total count will indicate figures for the total sum up of each one-round-count, along with the indication of the one-round-count.

A further description will be given hereinunder with regard to a way to count the numbers of piled up sheets of paper by means of a second preferred embodiment.

A disadvantage of the first preferred embodiment of the sensing device is that a piezo electric element thereof is not capable of generating electricity with a high enough efficiency, whereby provision of an amplification circuit is required to increase the applied voltage therein, with no regard for a higher cost thereof, since the probe 3 is adapted to effect an up-and-down movement to inflict only a lengthwise pressure upon the piezo electric element along the axis thereof. The second preferred embodiment is however improved to eliminate the above-mentioned disadvantage therefrom.

The thus improved sensing device 32 is placed onto the slanted slope defined by the side edge portions of piled up sheets of paper in the same manner as in the case of the first preferred embodiment, in order that the probe 36 scans therealong with its foremost end portion to be brought into contact with said slanted slope.

When the foremost end of the probe 36 moves along the slope arranged in tiers b, that is, from the side edge portion of one sheet a to that of the lower sheet, as shown in FIG. 10 from a position illustrated by a broken line to that by a solid line, the probe 36 is inflicted a shock which initiates an oscillation of the probe 36. This oscillation is applied to the piezo electric element 43 through the intermediate of the fixing point f within the supporting rubber 39 and the fixing points e, d of the cushion rubber 44.

It is through the cushion rubber portion 44 that the oscillation of the probe is largely applied to the piezo electric element 43. At its end adjacent the fixing point f to the supporting rubber 39, a strain occurs in the piezo electric element in proportion with the magnitude of oscillation of the probe 36 initiated by the shock, producing the voltage seen in FIG. 6.

On this occasion, the supporting rubbers 39, 40 absorb the natural oscillation of the probe 36, but do not intercept transmission of oscillation initiated by the shock of the probe.

Provision of the cushion rubber 44 leads the movement of the piezo electric element 43 as well as the probe to be centered around the fixing point f, in the same direction with the same phase; accordingly a slow and gentle movement of the probe 36 effects a slow and gentle movement of the piezo electric element that results in a very small output therefrom.

Thus, it can be said that provision of the cushion rubber 44 is very advantageous in that it can serve to magnify the difference between the output due to the oscillation initiated by the shock of the probe and any output resulting from other causes except said shock.

The aforementioned shock initiates an up-and-down oscillation of the probe 36. Meanwhile, the fixing points d, e, f defined between the probe and cushion rubber 44, between the piezo electric element 43 and cushion rubber 44, and between the supporting rubber 39 and the probe, together with the piezo electric element, are induced to oscillate by said shock. As a rule, however, a mode of oscillation is to be determined by the distance between the fulcrums; in this regard, the oscillation between each fulcrums d, e, f cooperate to form an integrated oscillation to be applied to the piezo electric element 43.

With reference to FIG. 10, it can be understood that it is the natural oscillation of a closed loop of e - 44 - d - 36 - f - 43 - e that determines the waveform of the electric output.

Application of the thus effected oscillation to the piezo electric element 43 induces the latter to generate an output with such a waveform as seen in FIG. 6, in a similar manner to the piezo electric element 9 of the first embodiment. The thus generated output is fed into the electronic counter 25 by line 12 through the intermediate of the wave-shaping circuit 51 and preamplifier 42, for achievement of the digital counting and indication of the result therefrom.

The practical utilization of this preferred embodiment of the present invention proves that an output of 2 - 5 V is obtainable from piled up sheets of paper with thickness of 0.15 m/m, and an output of 3 - 7 V from the sheets with thickness of 0.24 m/m.

Even from counting the numbers of sheets of paper as thin as 0.1 - 0.25 mm, there may be obtained a result as accurate as nearly 100 percent.

Although particular preferred embodiment of the invention have been disclosed hereinabove for the purpose of illustration, it will be understood that variations or modifications thereof which lie within the scope of the invention as defined by the appended claims are fully contemplated.

For example, provision of a rotary switch to the electronic counter may suitably change resistance within the wave shaping circuit, as required, so as to accord with the counting of the sheets with varying thickness, for instance, such as thin, mediumly thin, mediumly thick, and thick sheets. Further, the lead line 12 of the sensing device can be preferably connected with a control box of electronic counter through the intermediate of a connector.

Claims

What is claimed is:

1. An apparatus for counting a number of piled up sheets of paper comprising:

a sensing device having a case, a probe disposed oscillatably within said case and with the foremost end of said probe projecting outwardly from the case, and a piezo electric element disposed in said case, said piezo electric element being connected to said probe so as to generate an electric signal due to oscillation of said probe, said probe being resilient, said piezo electric element being positioned parallel with the probe with a predetermined space therebetween, an intervening cushion rubber connecting the foremost end of said piezo electric element to an intermediate portion of said probe, said probe and piezo electric element both having base end portions, said base end portions being fixedly attached to each other at a fixing point, spaced supporting members in said case, said base end portions being elastically supported by one said supporting member at said fixing point, said probe including a portion slightly offset from said intermediate probe portion toward said foremost probe end and elastically supported by the other said supporting member; and

an electronic counter connected with said sensing device to count signals transmitted from said piezo electric element in order to indicate figures for the counted number of sheets.

2. The apparatus of claim 1 in which the foremost end of the case defines a slanted, plate-like wall having a slit, the foremost end of said probe being bent downwardly and extending through said slit sufficiently to scan along the side edge portions of the piled up sheets adjacent said plate-like case wall, said other supporting member being spaced inboard in said case from said slanted foremost end wall, said probe extending freely from said other supporting member through said slit.

3. The apparatus of claim 2 in which the foremost end of said probe is about 100.mu. thick and about one mm wide, the remainder of said probe being about 0.2 mm thick and about 2 mm wide.

4. The apparatus of claim 3 in which said foremost end portion of said probe is of stainless material, the remainder of said probe being of phosphor bronze plate.

5. The apparatus of claim 2 including hollow pipe-like means fixedly attached within said case, said supporting members being fixed at each end of said pipe-like means, said piezo electric element and the adjacent portion of said probe and said cushion rubber all being disposed within said pipe-like means, said pipe-like means being spaced from the foremost end of said case, wave shaping circuit means disposed in said case rearwardly of said pipe-like means for applying the output of said piezo electric element remotely to said electric counter.

6. The apparatus of claim 1 including a wave shaping circuit connecting the output of said piezo electric element to the input of said electronic counter, said wave shaping circuit being adapted to be disposed within said case, said wave shaping circuit including means for removing half cycles of one polarity from the piezo electric element output waveform and further means for converting the resultant waveform to an array of one or more pulses and still further including a monostable multi-vibrator timed for producing, from said last mentioned pulses, a single output pulse for each sheet edge struck by said probe, said output pulse being sufficiently long to mask the later phases of piezo electric element output oscillation, but not overlapping the next output pulse to be generated from striking of a new sheet edge portion by the probe, said supporting members permitting transmission of the oscillation initiated by the shock of probe contact with a new sheet edge portion but thereafter absorbing part of the continued probe oscillations, whereby to damp the natural oscillation of the probe.