CA2089216C - Vibratory bowl - Google Patents

Abstract

An improvement in a feeding and orientation system for components having a stem and head such as rivets which utilizes a trough having at least one step formed therein and whereby, through vibration, the rivets are oriented in their correct longitudinal direction for delivery to an outlet. The system is particularly suitable for components wherein the head diameter approximates the stem length.

Description

2~~~~1~
The present invention relates to feeding and orientation systems and more particularly, relates to improvements in feeding and orientation systems for small articles characterized by having a stem portion and a head portion, examples of which are rivets, nails, screws, etc.
The automated feeding of relatively small components such as rivets, electronic components, nails, screws, is well known in the art and many machines exist for the feeding of such components (which normally are packaged in bulk) to a machine which will then be able to take the individual component and utilize it in the manner for which it is intended. Thus, for example, in the electronic industry, automated feeders are utilized to feed the components to pick and place machines which take an individual component and place it on the circuit board in the desired position. Similarly, systems are know~~for taking articles such as rivets and feeding them to an automated riveting apparatus.
Generally, such systems for feeding individual components function well and in one common arrangement, the components are fed to a vibratory bowl system which consists of a bowl and associated vibrator. The bowl is vibrated by suitable means and components then advance along a track at the periphery of the bowl to an output location.
Components which are not properly oriented are usually automatically rejected by a mechanical sorting means as they proceed along the track.
In the case of objects which have a stem and associated head such as rivets and screws, the systems have a high degree of reliability as long as the stem has a length which is sufficiently greater than the diameter of the head portion. However, when the length of the stem approximates or is less than the diameter of the head, problems occur in properly aligning the components. This problem is compounded when a machine is obligated to select from a number of different sources of like components. A particular example is in the case of rivets wherein the riveting of an article may require different size rivets at different locations. In such an instance, usually a different vibratory bowl is required for each size rivet and one then has a problem of feeding the different rivets to a common point where the riveting apparatus may take the desired rivet.
It is an object of the present invention to provide an automated feed and orientation system which overcomes the above disadvantages and which can feed components having a stem and a head portion wherein the stem length approximates the head diameter.
In one aspect of the present invention, in a system for feeding components having a stem and a head at one end thereof, there is provided the improvement of an orientation section, the orientation section comprising a base member having a trough formed therein, the trough having a cross sectional configuration defined by a pair of opposed side walls, the distance between said side walls being larger than the diameter of the head of the component to be fed, means for vibrating the base member, the trough having at least one step formed therein.

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In greater detail, the present improvement can be incorporated into many different component feed arrangements.
It can be used as a dedicated system for one size of component or alternatively, may be utilized in conjunction with the feeding of many different types of components.
As previously mentioned, the improvement of the present invention can be utilized with different types of components, all of which are characterized as having a head and stem arrangement. For ease of explanation, the description will refer to rivets, although as will be appreciated in the art, adaptation of the system to such other components may easily be accomplished.
The improvement may form a portion of an overall system which can be placed in line in such a system.
Alternatively, with the provision of a suitable inlet feed to the present invention, it may be utilized as a stand alone feeding and orientation arrangement. For present purposes, it will be described as having suitable means for heating to the inlet or entry of the orientation portion.
As mentioned, the inlet to the orientation section can be any desired, although in one conventional type of arrangement, a plurality of vibratory bowls are provided from which the desired size rivet or other component may be selected. This component will then be delivered to the feed system of the present invention. The means of delivering the same may vary from a simple slide to the use of compressed air or the like.
The orientation section will include a base member having a longitudinally extending trough into which the rivet

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is placed. The trough may have several different cross sectional configurations. Thus, it may have a somewhat V-shaped configuration or alternatively, may be in curved arcuate configuration. For ease of explanation, the present description will refer to the trough as being defined by a pair of opposed side walls. As aforementioned, a the trough may have a V-shaped configuration or some arcuate form. It will be understood that the side walls will merge at the bottom of the trough and wherein reference is made to the distance between the side walls, this will refer to the spacing at the upper portion of the trough. Normally, the distance between the side walls is adapted to be slightly greater than the diameter of the head portion of the rivet.
The trough thus forms the path or track which the rivet will follow and as such, may be slightly inclined downwardly although this is not required. Formed within the trough is at least one "step" wherein the trough has a sharply downwardly extending step formed therein.
Preferably, at least a pair of such steps are provided.
Means are also provided for vibrating the base member containing the trough and to this end, many suitable means may be employed. Linear vibrators are well known in the art and there are many suitable devices commercially available. The vibration may either be accomplished directly or transferred indirectly from other systems which also undergo a vibratory operation.
The purpose of the step or steps formed in the trough is to align the rivet in the correct direction either with the head leading or trailing. It does not matter which

- 5 -of the foregoing orientations is achieved; one of them will suffice for delivery at the output of the trough.
The above arrangement prevents the rivet from being in a sidewards orientation and allows proper delivery of the rivet at the output.
At the output of the trough, the rivet is delivered to a transfer arrangement to a system which can then utilize the rivet. This transfer will be dependant on the particular requirement, but a typical system would use a pair of guide rails such that the rivet will fall and be oriented such that the main body portion extends downwardly and the head portion rests on a pair of guide rails.
Having thus generally described the invention, reference will be made to the accompanying drawings illustrating an embodiment thereof, in which;
Figure 1 is a top elevational view of a rivet feeding and orientation system;
Figure 2 is a side sectional view taken along the lines 2-2 of Figure 1;
Figure 3 is a cross sectional view taken along the lines 3-3 of Figure 2;
Figure 3a is a view similar to Figure 3 illustrating a modified version thereof;
Figure 4 is a sectional view taken along the lines 4-4 of Figure 2;
Figure 4a is a view similar to Figure 4 illustrating operation of a rejection sub-system;
Figure 5 is a detailed view of the step portion of

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the trough; and Figure 5a is a view similar to Figure 5 showing alignment of the rivets.
Referring to the drawings in greater detail and by reference characters thereto, there is shown in Figure 1 an automated rivet delivery system which comprises a component selection and feed system generally designated by reference numeral 10; a transfer duct 12, a vibratory orientation device 14, and a slide section 16.
Component selection and feed system 10 may be selected from any number of known types of systems and arrangements. Thus, system 10 may include, for example, a single feed system typically formed of a vibratory bowl or alternatively, may include a plurality of vibratory bowls having discharge means associated therewith, and which discharge means feed to transfer duct 12.
From transfer duct 12 the individual rivets are fed to vibratory orientation device 14. Vibratory orientation device 14 includes, as best seen in Figures 2, 3 and 5, a base member 18 having a trough 20 formed therein. A
housing 22 surrounds base 18 and adjacent the portion where rivets 30 are transferred to the vibratory orientation device 14 there is provided a deflector member 24.
Typically, transfer is accomplished by means of compressed air and there are provided a plurality of outlets 29 in deflector 24 and side wall of housing 22 to permit exit of the air.

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As will be seen in Figure 3, groove or trough 20 has a semi cylindrical configuration with a pair of side walls 26 and 28. In the embodiment of Figure 3a, side walls 26 and 28 have a greater height and are spaced apart such that the width of trough 20 is substantially greater.
Also, in Figure 3a, the walls form a more or less V-shaped configuration. It suffices to say that any number of different configurations may be utilized in the practice of the present invention.
Each rivet, as may be seen from, has a stem portion 32 and a head portion 34. As shown in Figures 2, 3, 3a, 5 and 5a, the rivet when it originally enters groove or trough 20 can assume any orientation which is merely a product of chance.
As shown in Figures 2, 5 and 5a, base portion 18 and trough 20 which is formed therein have three sections;
a first section being designated by reference numeral 36, a second section 38 and a third section 40. Separating first and second sections 36 and 38 respectively, is a first step 42 while separating second section 38 and third section 40 is a second step 44. Thus, as may be seen in detail in Figures 5 and 5a, the steps comprise an area wherein the general plane of the trough 20 drops to a lower plane which is substantially parallel to the previous plane. Although two such steps are shown in the illustrated embodiment, it will be understood that one may utilize a single step and/or a multitude of such steps.
Vibratory means are used to apply or impart a vibration to base 18. Any number of such linear vibrators _ g _ are well known in the art and are used such as in the vibratory bowl itself.
It has surprisingly been found that by forming steps in trough 20, in conjunction with the use of vibration, the rivets will tend to orient themselves in a longitudinal direction. With a member wherein the stem is substantially longer than the diameter of the head, the longitudinal orientation is very easy to achieve. However, with those rivets which have a stem length which approximates the diameter of the head (in other words, a substantially square configuration), it has traditionally been a problem since they will often go down a groove sideways and stay in that orientation. However, with the practice of the present invention, it has been found that the step configuration formed within the groove provides the proper longitudinal orientation to the rivets.
Thus, referring to Figure 5, it will be seen that the rivets in the proper longitudinal orientation will, as shown in dotted line, continue in such orientation after passing by the step. Referring to Figure 5a, a rivet 30 which is oriented in a general transverse direction to the longitudinal length of drop 20 will, after passing over the step, tend to reorient itself in the proper longitudinal direction.
Following orientation of the rivets, they then enter a slide section which consists of a pair of rails 46 and 48. Rails 46 and 48 may be adjustable (or alternatively only one may be adjustable) in order to provide for different size rivets. Following placement on rails 46 and 48 which 2~~92~
define a track, the rivets slide down to the end thereof where they are presented to a conventional riveting apparatus.
As shown in Figures 4 and 4a, rivets 30, when delivered to slide section 16, align themselves such that stem 32 fits between rails 46 and 48 while head 34 rides on the top. To assist in the movement of rivets 30 along rails 46 and 48, vibration may also be utilized.
Rails 46 and 48, as above mentioned, may be adjustable and suitable means may be provided for adjusting the same. Thus, one or both of rails 46 and 48 may be mounted on a suitable shaft which is rotatably driven as shown in outline by a gear arrangement 50 and 52 for rails 46 and 48 respectively.
As shown in Figures 4 and 4a, a rejection system for improperly oriented rivets may be provided. This rejection system may comprise a tube 54 connected to a source of pressurized air. As shown in Figure 4, when a rivet is properly aligned, the pressurized air will not act on the rivet. As shown in Figure 4a, an improperly aligned rivet will be sent to a rejection outlet 54 which, as shown in Figure 1, may be connected back to the feeding system. The air may or may not operate all the time; in one embodiment, there may be a sensor to detect when a rivet is not properly aligned and the air is only operative at that point in time.
It will be understood that the above described embodiment is for purposes of illustration only and that changes and modifications may be made thereto without departing from the spirit and scope of the invention.

Claims (7)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. In a system for treating components which have a stem and a head at one end thereof, the improvement comprising an orientation section, said orientation section comprising a base member having a trough formed therein, said trough having a cross sectional configuration defined by a pair of opposed side walls, the distance between said side walls being larger than the diameter of the head of the component to be fed, means for vibrating said base member, said trough having at least one step formed therein.

2. The improvement of Claim 1 wherein said trough has a plurality of steps formed therein.

3. The improvement of Claim 2 wherein said trough has a semi spherical cross sectional configuration.

4. The improvement of Claim 2 wherein said trough has a generally V-shaped configuration.

5. The improvement of Claim 1 or 2, wherein said trough has an inlet and an outlet, said outlet being adapted to feed said components to a track member defined by a pair of spaced apart rails, wherein said head portion will ride on top of said rails and said stem portion fit between said rails.

6. The improvement of Claim 1 or 2 wherein said vibratory means comprises a linear vibrator.

7. The improvement of Claim 1 or 2 further including means for rejecting components at the outlet of said trough when said components are not longitudinally oriented.