US2689737A

US2689737A - Needle holding means for pickup

Info

Publication number: US2689737A
Application number: US97809A
Authority: US
Inventors: David J Munroe
Original assignee: Webster Electric Co Inc
Current assignee: Webster Electric Co Inc
Priority date: 1949-06-08
Filing date: 1949-06-08
Publication date: 1954-09-21
Anticipated expiration: 1971-09-21

Description

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Sept. 21, 1954 Filed June 8, 1949 D. J. MUNROE 2,689,737

NEEDLE HOLDING MEANS FOR PICKUP 2 Sheets-Sheet 1 m his IN V EN TOR.

flag/id J M 22/727126, M, Muzak Sept. 21, 1954 D. J. MUNROE 2,689,737

NEEDLE HOLDING MEANS FOR PICKUP Filed June 8, 1949 2 Sheets-Sheet 2 154 20 62 n 7 7 Z E 7 "u" 32 film-"1 Q. L 15 7g 93 INVENTOR.

Patented Sept. 21, 1954 NEEDLE HOLDING MEANS FOR PICKUP David J. Munroe, Racine, Wis., assignor to Webster Electric Company, Racine, Wis., a corporation of Delaware Application June 8, 1949, Serial No. 97,809

12 Claims. (01. 27437) The present invention relates to a pickup and has for one of its primary objects the provision of a new and improved reproducer or pickup adapted especially for the reproduction of sound.

Another object of the present invention is the provision of a new and improved pickup charac terized by novel stylus or needle holding means.

A further object of the present invention is the provision of a new and improved multiple needle pickup in which the needles are selectively usable for the reproduction of sound from difierent types of records, such as conventional and long playing records.

In brief, the pickup of the present invention includes a housin surrounding a transducer of suitable construction e. g., of the crystal type, and from the interior of which there projects a plurality of needles for playing different types of records. The needles are detachably secured to a needle chuck also mounted within the housing and operatively connected to the transducer, the chuck being constructed so as to permit easy and certain insertion of the needles into proper positions in the chuck as well as holding them in position. For this, the chuck is provided with an aperture into which is placed a needle positioning and holding element structurally correlated with the needles so that the latter are readily insertable only into their proper places. The arrangement is also such that a single needle securing screw can be used for holding the needles.

Other objects and advantages of the present invention will become apparent from the ensuing description of an illustrative embodiment thereof, in the course of which reference is had to the accompanying drawings, in which:

Fig. l is an enlarged top plan view of a pickup constructed in accordance with the invention;

Fig. 2 is a longitudinal vertical cross sectional view taken along the line 2-2 of Fig. 1;

Fig. 3 is a fragmentary enlarged vertical cross sectional view, partly in section, better illustrating the details of construction of the needle hold ing means;

Fig. 4 is a longitudinal horizontal cross sectional view taken along the line 44 of Fig. 2;

Fig. 4-A is a fragmentary further enlarged view similar to Fig. 4;

Fig. 5 is an end elevational view;

Fig. 6 is a transverse cross sectional view of the shank of the conventional playing needle;

Fig. 7 is a transverse cross sectional view of the shank of the long playing needle;

Fig. 8 is a side elevational view of a needle locating and holding element forming part of the needle holding means of the present invention. The view illustrates the element in an intermediate stage obtaining before it is securedto the chuck;

Fig. 9 is across sectional view illustrating a resilient positionin and holding tongue, the view being taken along the line 99 of Fig. 8; and

Fig. 10 is an enlarged fragmentary plan view of the chuck illustrating it prior to insertion of the needle holding element therein.

Referring now to the drawings, it may be noted that the pickup, which is indicated generally by the reference character if) comprises a housing I2 includin like opposed portions l4 and It secured together in suitable manner as by rivets IS. The housing portions can be stamped from metal or molded from some suitable plastic material.

The pickup illustrated is of the multiple needle type for playing records of different types such as conventional and long playing records. It includes a needleZl'l for playing conventional records and a needle 22 for playing the long playing records. These needles may be any desired construction, as illustrated, needle 20 includes a shank 24 and needle 22 includes a shank 26, the shanks being secured to the remainder of the needle structure in a desired manner, as by soldering, welding or swaging. The shanks however are of novel construction to facilitate location, as will be pointed out in detail hereinafter.

The needles project beyond the housing through apertures 21 therein so that they may be selectively positioned to engage a record. According to one arrangement the pickup can be supported for rotation in a tone arm (not shown) along its longitudinal axis so that one or the other of the needles extends downwardly for engagement with a record placed on a turntable. The means for rotatably securing the pickup includes the forwardly extending structure 28 having a bifurcated end 32 secured to the housing by the rivets H3. The rear end of the cartridge is adapted rotatably to be supported by means not shown, but which may be like that disclosed in the co-pending application of Clarence F. Jensen, Serial No. 82,315, filed March 19, 1949, now abandoned.

A suitable electro-mechanical transducer 32, which is illustrated as being of the twister crystal type, but which may be of other types, is mounted within the housing for actuation by one or the other of the needles through a needle; holding chuck 34 provided with spaced clamping jaws 36 at one end adapted to embrace and to be secured to the transducer. A dampingstrip 38 can be placed between jaws and crystal.

The chuck is movably supported within the housing for limited torsional movement about its longitudinal axis. It is so supported by spaced

trunnions

39 and 30 in rubber bearings 4i and 42 which are held, in compression by restricted portions 44 and 33, respectively, of the housing sections.

The electrical connection to the crystal is mad-e through the terminals 50 secured to the rear end of the housing and connected by conductors 52 to the crystal. The conductors are insulated from the casing by insulating strips 54.

In accordance with the present invention, the needles are detachably secured in the chuck in a novel manner so that they can be readily replaced and by a structure and arrangement that is simple and inexpensive and also light.

Referring now more particularly to Figs. 3, 4, 8 and 9, the needle holding means .of the present invention includes, in the main, a needle locating and holding element 60 adapted to be inserted into an aperture 62 in the portion of the chuck between the trunnions and substantially aligned with the openings 27 in the housing through which the needles project. The element is constructed and arranged relative to the chuck so as to provide spaced openings for reception of the needles, to provide stops for needle location, to provide means resiliently holding at least one needle, and to enable a single securing screw to hold two needles in the chuck.

The locating and holding element 60 is readily stamped from some suitable material, preferably resilient, such as beryllium copper .012 inch thick. In the manufacturing of this element, thereis formed a longitudinally extending tongue 66 which is generally V-s'haped in cros section, as illustrated in Fig. 9. One end of the element is bent at right angles to the main part to provide a transversely extending flange 68 adapted to project over the flat surface 10 at one side of the chuck. The aperture 62 is provided with opposed slots 12 to facilitate insertion of the element in the aperture so that the flange 68 will abut against the surface l0 and to permit some movement of the element lengthwise of the aperture. After insertion the opposite end of the element is bent over as indicated by the reference character 14 to abut against the opposite flat surface on the chuck. The element is inserted so that the tongue projects rearwardly of the pickup housing.

The element 60 acts as a locating and holding means for the needles. The flange portions 68 and M act as stops limiting the movement of the needle shanks when the needles are inserted into the chuck. The tongue 66 is convex in back in order to cooperate with a generally V-shaped groove 78 in the shank 24 of the conventional needle 20, thereby to indicate to the user that this needle is properly located when it is placed into the chuck in cooperative relationship with the tongue. The tongue also resiliently holds the shank and needle 20 when the needle is inserted into place so that it need not be held while the other needle is being inserted. The other shank 26 is provided with a flat surface 80 to cooperate with the fiat end surface 32 of the opening 62 in the needle chuck. The back side of the shank is circular and rests in the concave front of the tongue 66 and the back of shank 2'4 abuts against the vertical slot 83 for better positioning and holding of the needles when a securing screw 84,

having threaded engagement with an internal opening 86 at the forward end of the chuck, is turned positively to hold both needles in the chuck.

Damage to the needles by the application of excess pressure to the tone arm is prevented by the opposed arms 96 which are of generally U configuration, as best illustrated in'Fig. 5. The bights are reversely bent slightly, as indicated by reference character 92, in line with the needles. The protecting structures are secured to the housing by the rivets 94.

From the foregoing detailed description of the invention it is apparent that the pickup of the present invention is simple and inexpensive to construct and that it provides a light and otherwise very satisfactory means for detachably and yet securely fastening needles to the chuck. In construction, the chuck is constructed with aperture E2, the needle locating and holding element is 60 stamped with the tongue 66 and flange 68. The element is then inserted into the opening '62 and in alignment with the slots 12 and the flange 14 bent over to secure the element to the chuck. The cartridge is then assembled in the usualmanher and made ready for reception of the needles 2D and 22. The former is first inserted because it can be inserted readily into its place with its groove 1'8 abutting against the tongue 66, whereby it is held in place. Needle 22 is then inserted so that its flat side abuts against flat side 82 of the aperture and screw 86 is. turned until both needles are secured positively in the chuck. The slots 12 are somewhat wider than the thickness of the holding element in order that the latter may have some longitudinal movement, whereby the securing screw .84 is effective to hold both needles, it acting on the rear needle shank 24 through the tongue 66 and the front needle shank 25,.

While the present invention has been described in connection with specific detail of an illustrative embodiment it should be understood that these details are not intended to be limitative of the invention except insofar as set forth in the accompanying claims.

Having thus described my invention what I claim as new and desire to secure .by United States Letters Patent is: v

1. A pickup chuck including needle holdin structure defining needle shank receiving openings spaced longitudinally of the chuck and including a resilient portion between said openings normally projecting into one of said openings to hold a needle inserted into said one opening, said. resilient portion having a convex back side, and a needle with a shank having a concave groove adapted to receive said resilient portion.

2. A pickup including a chuck having a generally rectangular aperture therethrough, the front wall of .said aperture being flat and the rear wall having a central vertical slot, needle holding structure including a central portion extending through the aperture and cooperating with the aperture walls to define needle shank receiving openings spaced longitudinally of the chuck, said central portion including a resilient tongue disposed between said openings and normally projecting into one of them, needles insertable into said openings, one of said needles having a circular shank with a fiat surface engageable with the fiat front wall of the aperture and the other having a circular shank witha V-shaped groove, and said resilient tongue having a V-shaped cross section whereby it fits into the groove in the other needle shank, and a screw movably mounted in the chuck and engageable with the flat side of said one shank forholding both needles in the chuck.

3. A pickup including a chuck having a generally rectangular aperture therethrough, the front wall of said aperture being flat and the rear wall of which has a central vertical slot, needle holding structure including a central portion extending through the aperture and cooperating with the aperture walls to define needle shank receiving openings spaced longitudinally of the chuck, said central portion including a resilient tongue disposed between said openings and normally projecting into one of them, said resilient tongue having a -shaped cross section with the apex of the v aligned with said slot, and a screw movably mounted in the chuck for movement into one of said openings through the front wall of the aperture.

4. A pickup including an apertured chuck, a needle holding and locating element including a central longitudinally extending portion extending through the aperture and spaced from the aperture walls to provide a pair of needle receiving openings, and transversely extending flanges at its ends engaging opposite sides of the exterior of the chuck for securing said element to the chuck and constituting stops for needles inserted into the needle receiving openings.

5. A pickup including an apertured chuck, a needle holding element including a central longitudinally extending portion extending through the aperture and spaced from the aperture walls to define spaced needle receiving openings, said element having transversely extending flanges at its ends engaging opposite sides of the exterior of the chuck for securing said element to the chuck, and said flanges extending in opposite directions across the ends of the aperture thereby to define stops for needles inserted into the aperture from opposite sides of the chuck.

6. A pick-up including a chuck having a generally rectangular aperture therethrough, the front wall of said aperture being flat, needle holding structure including a central portion extending through the aperture and cooperating with the aperture Walls to define needle shank receiving openings spaced longitudinally of the chuck, said central portion including a resilient tongue disposed between said openings and normally projecting into one of them, needles insertable into said openings, said resilient tongue and one of said needles having corresponding complementary shapes to position the needle within one of the openings, the other of said needles having a substantially circular shank including a flat tongue secured to said longitudinally extending "portion and extending longitudinally of the surface engageable with the front wall of the aperture to position it in the other of said openings, and a screw movably mounted in the chuck for movement into engagement with the fiat surface of the shank for holding the needles in the chuck.

7. A pick-up including an apertured chuck and a needle locating and holding element mounted in the aperture of said chuck, said element including a longitudinally extending portion in and spaced from a wall of said aperture, a needle insertable into said chuck, flanges extending transversely in opposite directions at the respective ends of said longitudinally extending portion for engaging the chuck so as to secure the element within the aperture, at least one of said flanges engaging the end of the needle inserted into the chuck in the space between the aperture wall and the longitudinally extending portion so as to constitute a stop for the needle, and a resilient needle inserted into the chuck so as to hold the needle therein.

8. A pick-up including an apertured chuck and a needle locating and holding element mounted in the aperture of said chuck, said element including a longitudinally extending portion in and spaced from a wall of said aperture, a needle insertable into said chuck, flanges extending in opposite directions at the respective ends of the longitudinally extending portion for engaging the chuck so as to secure the element within the aperture, at least one of said flanges engaging the end of the needle inserted into the chuck in the space between the aperture wall and the longitudinally extending portion so as to constitute a stop for the needle, the shank of said needle having a substantially V-shaped groove therein, a resilient tongue secured to said longitudinally extending portion and extending longitudinally of the needle inserted into the chuck so as to hold the needle therein, said tongue being provided with a substantially v-shaped surface for cooperation with the groove in the needle to properly position the needle in the chuck.

9. A pick-up including an apertured chuck, a needle holding and locating element including a central longitudinally extending portion extending through the aperture and spaced from the aperture walls to provide a pair of needle receiving openings, transversely extending flanges at opposite ends of the longitudinally extending portion for engaging opposite sides of the exterior of the chuck to secure said element to the chuck, each of said flanges extending over a different one of said openings in order to engage needles inserted into the needle receiving openings and to constitute stops for the needles, and a resilient member secured to said central longitudinally extending portion and extending longitudinally of a needle inserted into one of the openings in the chuck so as to hold the needle therein.

10. A pick-up including an apertured chuck and a needle holding and locating element mounted in the aperture of the chuck, a needle insertable into said aperture having a shank with a deformed longitudinally extending surface portion, said element including a resilient tongue having a free end extending into said aperture and longitudinally of the needle shank in order to engage the deformed surface portion of the shank, and said tongue and said deformed surface portion having complementary shapes in order to position the needle within the aperture.

11. A pick-up including a chuck having a generally rectangular aperture therethrou gh, the front wall of said aperture being flat, needle holding structure including a central portion extending through the aperture and cooperating with the aperture walls to define needle shankreceiving openings spaced longitudinally of the chuck, said central portion including a resilient tongue disposed between said openings and normally projecting into one of them, needles insertable into said openings, said resilient tongue and one of said needles having corresponding complementary shapes to position the needle within one of the openings, and the other of said needles having a circular shank with a hat surface engageable with the front Wall of the aperture to position it in the other of said openings.

12. A pick-up including a chuck with an aperture extending therethrough, a needle insertable into the chuck, a needle locating element spaced I from a wall of said aperture and slidably mounted therein and including a resilient tongue-like portion having one end formed integral with said element, having a free end remote from said one end extending into the aperture and engageable with the side of the shank of the needle, and said needle locating element having a stop defining portion at one end thereof extending transversely of the element and across one end of said aperture in order to engage the outside of the chuck and provide a stop for the end of the needle inserted into the chuck.

References Cited in the file of this patent UNITED STATES PATENTS Number Number Name Date Paul Dec. 3, 1918 Muller Jan. 7',- 1919 Capps Dec. 15, 1931 Miller Apr. 14, 1936 Kornei June 9, 1942 Hasbrouck Aug. 10, 1943 Andrews Aug. 23, 1949 Ketchum Dec. 18, 1951 FOREIGN PATENTS Country Date Great Britain Oct. 7,, 1929 Germany Sept. 21, 1933 Great Britain Jan. 1, 1947 Great Britain July 10, 1947