DEVICE FOR PREVENTING FALL OF BUTTON PARTS FROM A CHUTE

Abstract: A button attaching machine (10) has a chute assembly (15) for conveying button parts (B) and a blocking device (29) for preventing button parts from falling from a detachable intermediate chute (18) of the chute assembly when the intermediate chute is detached. The blocking device com­ prises a spring-loaded plunger (34) supported by the inter­ mediate chute adjacent to a lower end (18b) thereof and reciprocally movable in a plane perpendicular to the longitu­ dinal axis of the intermediate chute. The plunger is normally held in engagement with a lower chute (18) to retract away from a button-parts guide channel (19) of the chute assem­ bly, and upon detachment of the intermediate chute, it is movable into a blocking position where it is disposed below the channel and spaced from the lower end of the intermedi­ ate chute by a distance (L₁) which is small enough to block the passage of the button parts.

Description: The present invention relates to a button attaching machine comprising: a support; a reservoir mounted on an upper portion of said support for containing a multiplicity of button parts; a terminal guide mounted on a lower portion of said support; and a chute assembly for conveying the button parts successively from said reservoir to said terminal guide, said chute assembly including an upper chute connected to said reservoir, a lower chute connected to said terminal guide, an intermediate chute detachebly mounted on said support and extending between said upper and lower chutes so as to define jointly therewith a combined, uninterrupted channel for receiving and transporting the button parts in succession, a chute holder provided at the lower end of said intermediate chutes having each of said upper, lower and intermediate chutes having through its entire length a pair of confronting flanges defining therebetween a longitudinal aperture communicating with said channel, and a blocking device adapted to be supported by said intermediate chute adjacent to a lower end thereof for preventing the button parts from falling from said intermediate chute when the latter is detached, said blocking device including a blocking member reciprocally movable in a plane perpendicular to the longitudinal axis of said intermediate chute, and an operating member integral with said blocking member and being normally held in engagement with a stationary part of the machine to retract said blocking member away from said channel and, upon detachment of said intermediate chute, movable into a blocking position where said blocking member is disposed below said channel and spaced from said lower end of said intermediate chute by a distance which is small enough to block the passage of the button parts; and resilient means acting on said operating member for urging the latter toward said blocking position. A button attaching machine of the type mentioned above is disclosed in FR-A-483 903. This prior art button-attaching machine comprises a chute assembly including a stationary lower section and a detachable upper section. The detachable upper chute section is provided with a blocking device. This blocking device consists of a two-armed lever swingably mounted in the chute. The lower arm of this lever forms a blocking portion, and its upper arm forms an actuation portion. If stalled, the upper arm of the two-armed lever rests against a fixed portion of the machine, and the lower arm, i.e. the blocking portion, is thereby kept outside the chute against the force of a spring, so that the feed of the buttons is not blocked. If, however, the upper chute section is detached from the machine, the two-armed lever is swung by the spring, so that the blocking portion closes the lower end of this chute section and prevents the buttons contained therein from falling out. One drawback of this known blocking means resides in that the engagement or disengagement, respectively, of the lower arm of the two-armed lever forming the blocking portion depends on whether the upper arm comes into engagement with the corresponding fixed portion of the machine. This circumstance may cause wrong actuation of the blocking portion when stalling or removing the movable chute section into or from the machine, respectively. Therfore it is possible that buttons fall out when this chute section is installed or removed. One further drawback is that the stroke of the blocking portion is determined by the pivoting angle of the two-armed lever which itself, however, is dependent on the relative position between the movable chute portion and the fixed portion of the machine. If that relative position is not strictly adhered to - if, for example, the fixed portion does not project far enough towards the upper arm of the lever - there is the risk of its lower arm, i.e. the blocking portion, projecting into the chute and impeding the feed of the buttons. It is an object of the present invention to provide an improved button-attaching machine comprising a blocking device of great operational reliability. A button-attaching machine satisfying this requirement is characterized in that said chute holder includes a recess having an open end normally facing said lower chute, the opposite end of said recess being closed, said blocking member and said operating member being formed by a plunger reciprocably disposed in said recess and projectable therefrom through said open end for engagement with said lower chute, said resilient means comprising a compression coil spring disposed in said recess and acting between said closed other end of said recess and said plunger. In the button-attaching machine according to the present invention the blocking portion and actuation portion of the blocking device are integrated into one single component part, namely a plunger. This plunger is controlled by the upper end of the lower chute. This practically excludes any maloperation of the blocking device. If the intermediate chute is inserted into the chute assembly, the plunger compulsorily comes with its front face into contact with the upper end of the lower chute, and is shifted against the force of a pressure spring to the ineffective position where it does not impede feed of the buttons. However, if the intermediate chute portion is removed, the plunger is automatically shifted by the pressure spring to its effective blocking position, so that it closes more and more the channel of the intermediate chute if the lower end of the intermediate chute is moved perpendicularly to the upper end of the lower chute. Therefore it is not possible that buttons fall out when removing the intermediate chute. A preferred embodiment of the invention is described in detail below, reference being made to the accompanying drawings, wherein: Figure 1 is a fragmentary side elevational view of a button attaching machine having a blocking device embodying the present invention; Figure 2 is an enlarged fragmentary front elevational view of Figure 1, showing a chute assembly of the button attaching machine; Figure 3 is an enlarged cross-sectional view taken along line III-III of Figure 1; showing the details of the blocking device; Figure 4 is a view similar to Figure 3 but showing the blocking device in working position; and Figure 5, appearing with Figure 2, is an enlarged schematic view, partly in cross section, of a modified blocking device. As shown in Figure 1, a button attaching machine 10 has a support 11, a reservoir 12 mounted on an upper portion of the support 11 and containing a multiplicity of button parts B, a terminal guide 13 disposed at a lower portion of the support 11 and leading to a lower unit (not shown) of a button attaching station 14, and a chute assembly 15 for conveying the button parts B successively from the reservoir 12 to the terminal guide 13. The chute assembly 15 includes an upper chute 16 connected to the reservoir 12, a lower chute 17 connected to the terminal guide 13, and an intermediate chute 18 extending between the upper and lower chutes 16, 17 so as to define jointly therewith a combined uninterrupted channel 19 for receiving and transporting the button parts B in a row. Each of the chutes 16, 17 and 18 has through its entire length a pair of confronting flanges 20, 20 defining therebetween a longitudinal aperture 21 communicating with the channel 19. As shown in Figures 1 and 2, the intermediate chute 18 is detachably mounted on the support 11 by means of a pair of spaced retainers 22, 22, each including a first plate 23 secured to the support 11, a second plate 24 for clamping the intermediate chute 18 in cooperation with the first plate 23, and a screw 25 for fastening the second plate 24 to the first plate 23. The upper end 18a of the intermediate chute 18 is releasably connected to the lower end of the upper chute 16 by means of a rectangular first chute holder 26 secured to the upper chute 16, and the lower end 18b of the intermediate chute 18 is releasably connected to the upper end of the lower chute 17 by means of a rectangular second chute holder 27 secured to the intermediate chute 18. Each chute holder 26, 27 has through its entire width a groove 28 (Figure 2) for receiving the confronting ends of adjacent chutes 16, 18 and 17, 18. For detaching or removing the intermediate chute 18 from the machine 10, this may be done by loosening the screws 25 and the rotating the second plates 24 through an angle of 90 o , or alternatively simply removing the second plates 24. As shown in Figure 3, the machine 10 includes a blocking device 29 mounted in the second chute holder 27 for preventing the button parts B from falling from the intermediate chute 18 when the latter is removed. The chute holder 27 that carries the blocking device 29 is secured by a screw 30 to the bottom wall 31 of the intermediate chute 18 opposite to the confronting flanges 20, 20 and near the lower end 18b of the chute 18. The second chute holder 27 has an elongate cave or recess 32 extending in a plane perpendicular to the longitudinal axis of the intermediate chute 18 for retaining therein the blocking device 29. The recess 32 is open at one end through a reduced diameter portion 32a and closed at the other end 32b by an externally threaded bush 33. The blocking device 29 includes a blocking member in the form of a plunger 34 movably received in the recess 32. The plunger 34 has a cylindrical body 34a of a diameter slightly smaller than that of the reduced diameter portion 32a so that the plunger body 34a can move therethrough, and an enlarged spring retainer head 34b joined with an inner end of the plunger body 34a. The blocking device 29 further includes a compression coil spring 35 interposed between the retainer head 34b and the bush 33 threaded into the the opposite end 32b of recess 32. The plunger 34 is normally urged by the spring 35 toward and rests against the bottom wall 17a of the lower chute 17 adjacent the upper end thereof abutting against the lower end 18b of the intermediate chute 18. The upper pheripheral edge of the plunger body 34a is positioned slightly below and spaced apart from the lower end 18b of the intermediate chute 18 by a distance L₁ which is small enough to block the passage of the individual button parts B. In the illustrated embodiment, the button parts B have a circular shape of a maximum diameter L₂, the distance L₁ is smaller than the diameter L₂ of the button parts B so that when the intermediate chute 18 is released from the lower chute 17, the plunger 34 is forced by the spring 35 to move into a blocking position disposed blow the channel 19 and traps the latter from falling from the intermediate chute 18, as shown in Figure 4. Upon completion of the machine operation or when otherwise desired to remove the intermediate chute 18, this can be done simply by disconnecting this chute 18 by hand from the lower chute 17 without the fear of letting the buttons B drop from the intermediate chute 18 on to the floor. When reassembling the intermediate chute 18, this can be done simply by holding the plunger 34 against the wall 17a of the lower chute 17 until it is retracted to normal position of Figure 3 against the force of the spring 35. Figure 5 shows a second embodiment of the invention in which the mounting position of a second chute holder 36 is reversed; that is, a blocking device 37 is mounted in the chute holder 36 such that it is positioned to face the channel 19 of the chute assembly 15. The second chute holder 36 is secured by a pair of screws 38, 38 to opposite sides of the intermediate chute 18 adjacent the lower end 18b thereof. The blocking device 37 is substantially the same in construction and operation as that of the first embodiment already advanced, except that a spring-loaded blocking member or plunger 39 has a cylindrical plunger body 39a having a diameter D₁ which is larger than the distance L₃ between the confronting flanges 20, 20, so that it can normally rest against these flanges 20, 20 of the lower chute 17 under the force of the spring (not shown) without slipping into the channel 19 through the aperture 21 to block the passage of button parts B.

Claims: Button attaching machine (10) comprising: a support (11); a reservoir (12) mounted on an upper portion of said support for containing a multiplicity of button parts (B); a terminal guide (13) mounted on a lower portion of said support; and a chute assembly (15) for conveying the button parts successively from said reservoir to said terminal guide, said chute assembly including an upper chute (16) connected to said reservoir, a lower chute (17) connected to said terminal guide, an intermediate chute (18) detachably mounted on said support and extending between said upper and lower chutes so as to define jointly therewith a combined, uninterrupted channel (19) for receiving and transporting the button parts in succession, a chute holder (27) provided at the lower end (18b) of said intermediate chute (18) for connection thereof with an upper end of said lower chute (17), each of said upper, lower and intermediate chutes having through its entire length a pair of confronting flanges (20, 20) defining therebetween a longitudinal aperture (21) communicating with said channel, and a blocking device (29; 37) adapted to be supported by said intermediate chute (18) adjacent to a lower end (18b) thereof for preventing the button parts from falling from said intermediate chute when the latter is detached, said blocking device (29;37) including a blocking member reciprocally movable in a plane perpendicular to the longitudinal axis of said intermediate chute (18), and an operating member integral with said blocking member and being normally held in engagement with a stationary part of the machine to retract said blocking member away from said channel (19) and, upon detachment of said intermediate chute (18), movable into a blocking position where said blocking member is disposed below said channel (19) and spaced from said lower end (18b) of said intermediate chute (18) by a distance (L₁) which is small enough to block the passage of the button parts (B); and resilient means (35) acting on said operating member for urging the latter toward said blocking position, characterized in that said chute holder (27) includes a recess (32) having an open end (32a) normally facing said lower chute (17), the opposite end (32b) of said recess (32) being closed, said blocking member and said operating member being formed by a plunger (34; 39) reciprocably disposed in said recess (32) and projectable therefrom through said open end (32a) for engagement with said lower chute (17), said resilient means comprising a compression coil spring (35) disposed in said recess (32) and acting between said closed other end (32b) of said recess (32) and said plunger (34; 39). A blocking device according to claim 1, said open end (32a) of said recess (32) normally facing a side of said lower chute (17) which is opposite to said flanges (20,20) so that said plunger (34) rests against said side of said lower chute (17). A blocking device according to claim 1, said open end (32a) of said recess (32) communicating with said channel (19) through said aperture (21), said plunger (39) having a diameter (D₁) larger than the distance (D₃) between said confronting flanges (20,20).

Inventors: TAGA, YUKIO
Applicants: YOSHIDA KOGYO K.K.
Application year: 1986
Main classification: D05B3
IPC codes: D05B3, A41H37, B65G11