Push-Pull Latch Assembly for a Detachable Media Pick Mechanism

• US 20160177989A1
• Filed: 12/17/2014
• Published: 06/23/2016
• Est. Priority Date: 12/17/2014
• Status: Active Grant

• Current Assignee: Lexmark International Incorporated (Ninestar Corporation)
• Original Assignee: Lexmark International Incorporated (Ninestar Corporation)
• Inventors: Alagos, Angel Macuha, De La Cerna, Generoso Tebordo
• Granted Patent: US 9,446,919 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B65H 2402/51 Joints, e.g. riveted or magnetic joints
• CPC Class Codes: B65H 2402/60 Coupling, adapter or locking means
• CPC Class Codes: B65H 2403/40 Toothed gearings
• CPC Class Codes: B65H 2404/1521 rotating, pivoting or oscillating around an axis, e.g. parallel to the roller axis
• CPC Class Codes: B65H 2601/324 Removability or inter-changeability of machine parts, e.g. for maintenance
• CPC Class Codes: B65H 3/06 Rollers or like rotary separators B65H3/42 takes precedence
• CPC Class Codes: B65H 3/0669 Driving devices therefor
• CPC Class Codes: B65H 3/0684 on moving support, e.g. pivoting, for bringing the roller or like rotary separator into contact with the pile
• CPC Class Codes: F16B 21/071 the socket being integrally formed with a component to be fasted, e.g. a sheet, plate or strip
• CPC Class Codes: F16B 21/073 the socket having a resilient part on its inside
• CPC Class Codes: F16B 7/042 with a locking element, e.g. pin, ball or pushbutton, engaging in a hole in the wall of at least one tube
• CPC Class Codes: Y10T 403/591 having operating mechanism
• CPC Class Codes: Y10T 403/60 Biased catch or latch

Abstract

A push-pull latch assembly for a detachable media pick mechanism. The latch assembly comprises a handle that is slidably and axially insertable into a handle base which is mounted to the pick mechanism housing. The handle base includes a pair of cantilevered, opposed latched arms having opposed catches for engagement with a groove positioned adjacent to a free end of a cantilevered drive shaft for the pick mechanism. The handle includes triangular rails having inner and outer ramps used to separate the opposed latch arms. The outer ramp separates the latch arms when the handle is inserted into the handle base. The inner ramp separates the latch arms during removal of the pick mechanism from the drive shaft. An axial pushing force engages the latch assembly to the groove and an axial pulling force disengages the latch assembly from the groove allowing for pick assembly removal.

Claims

1. A detachable pick mechanism slidably engageable onto a cantilevered drive shaft having a groove, the detachable pick mechanism comprising:

a transmission housing having a top, a bottom, a first and a second side defining a cavity therein for containing a drive transmission, an opening in a rear portion of the transmission housing through which the cantilevered drive shaft passes, and a latch assembly mounted to one of the first side and the second side for rotatably engaging the cantilevered drive shaft to axially position the pick mechanism on the drive shaft, the latch assembly comprising;

a handle base mounted to a side of the transmission housing having an opening therethrough for receiving the drive shaft, the handle base including;

a guide arm; and

a first resilient latch arm and a second resilient latch arm forming a pair of opposed latch arms, each latch arm being in a deflected position having a catch at a free end thereof engaging the groove of the drive shaft when the pick mechanism is mounted thereon, the first and second latch arms and the guide arm depending from a same side of the handle base and being axially aligned with the opening in the handle base; and

,

a handle slidably retained in the handle base and axially movable therein, wherein, with the catches engaged with the groove, axial movement of the handle away from handle base flexes and separates the first and second latch arms disengaging the catches thereof from the groove allowing the pick mechanism to be removed from the cantilevered drive shaft.

2. The detachable pick mechanism of claim 1, wherein a length of the guide arm is greater than a length of the opposed pair of latch arms.

3. The detachable pick mechanism of claim 1, wherein the handle further comprises:

a support body having a first end and a second end and having an axial opening extending between the first and second ends and a channel axially extending along the support body from the first end and aligned with the guide arm and sized to receive the guide arm therein;

an end wall radially extending from the support body and positioned adjacent to the second end thereof; and

two opposed rails axially positioned between the first and second ends of the support body and aligned with a respective latch arm of the opposed pair of latch arms, each rail having a substantially triangular side profile, a first and a second end, and extending along the outer surface of the support body from adjacent the first end of the support body and having the second end spaced apart from the end wall forming a respective dwell gap therebetween sized to receive therethrough the catches of the opposed pair of latch arms.

4. The pick mechanism of claim 3, wherein the catch of each latch arm of the pair of opposed latch arms extends through the dwell gap and into the axial opening of the support body when the pair of opposed latch arms are in respective undeflected positions.

5. The pick mechanism of claim 3, wherein each rail of the two opposed rails includes:

an inner ramp having a bottom beginning adjacent to the second end of the rail and raising at a predetermined first acute angle; and

,

an outer ramp having a bottom beginning adjacent to first end of the rail and raising at a predetermined second acute angle, the first and second catches being moveable along respective inner and outer ramps,

wherein, during mounting pick mechanism onto the drive shaft using an axial pushing force applied to the handle, the free end of the drive shaft initially separates the catches and deflects the pair of opposed latch arms with the catches subsequently engaging the groove on the drive shaft and the latch arms returning to a less deflected position thereby latching the pick mechanism to drive shaft, and, during dismounting the pick mechanism from the drive shaft using an axial pulling force applied to the handle, the catches slide up the inner ramps of the two opposed rails and disengage from the groove in the drive shaft allowing the pick mechanism to axially slide off the free end of drive shaft.

6. A detachable pick mechanism, comprising:

a drive transmission having a drive shaft gear operatively connected to a pick axle gear, the drive shaft gear slidably engageable onto a cantilevered drive shaft extending from a housing;

a pick axle having a pick wheel mounted at each end, the pick axle operatively connected to the pick axle gear for rotating the pick wheels; and

a transmission housing having;

a top, a bottom, and a first side defining a cavity therein for containing the drive transmission and a side plate mounted over the cavity opposite the first side for enclosing the drive transmission; and

an opening in a front portion and in a rear portion of the transmission housing through which the pick axle and drive shaft, respectively, pass, the front portion dimensioned so that the surface of the at least one pick wheel extends beyond the top and the bottom of the front portion; and

,

a latch assembly mounted on one of the first side and the side plate for rotatably engaging a groove in the cantilevered drive shaft to axially position the pick mechanism on the drive shaft, the latch assembly comprising;

a handle base mounted on one of the first side and the side plate of the transmission housing having an opening therethrough for receiving the free end of the drive shaft therein, the handle base including;

a pair of opposed guide arms; and

a pair of opposed resilient latch arms, the pairs of opposed resilient latch arms and opposed guide arms depending from a same side of the handle base and being axially aligned with the opening in the handle base with each latch arm having a catch at a free end thereof; and

,

a handle slidably retained in the handle base and axially movable within the handle base, the handle including;

a support body having a first end and a second end, the support body having an axial opening extending between the first and second ends and a pair of opposed channels axially extending along an outer surface of the support body from the first end and aligned with the pair of opposed guide arms and receiving therein a corresponding guide arm;

a grip axially depending from a second end of the support body;

an end wall radially extending from the support body and positioned adjacent to the second end thereof; and

at least two opposed rails axially positioned between the first and second ends of the support body and aligned with a respective catch, each rail having;

a first and a second end and extending along the outer surface of the support body from the first end of the support body toward the second end of the support body, the second ends of the at least two opposed rails being spaced apart from the end wall and forming a respective dwell gap therebetween sized to receive therethrough the respective catches of the pair of opposed resilient latch arms;

an inner ramp having a bottom beginning adjacent to the second end of the rail and raising at a predetermined first acute angle; and

an outer ramp having a bottom beginning adjacent to first end of the rail and raising at a predetermined second acute angle with the first and second catches being moveable along respective outer and inner ramps,

wherein, during mounting of the pick mechanism onto the drive shaft using an axial pushing force applied to the handle, the free end of the drive shaft initially separates the catches and deflects the pair of opposed resilient latch arms with the catches subsequently engaging the groove on the drive shaft with the pair of opposed resilient latch arms returning to a less deflected position thereby rotatably latching the pick mechanism to the drive shaft, and, during dismounting of the pick mechanism from the drive shaft using an axial pulling force applied to the handle, the catches slide up the respective inner ramps of the at least two opposed rails and disengage from the groove in the drive shaft allowing the pick mechanism to axially slide off of the free end of drive shaft.

7. The detachable pick mechanism of claim 6, wherein the drive shaft gear has a center opening having a plurality of axial grooves engageable with a at least one radial spline on the drive shaft.

8. The detachable pick mechanism of claim 6, wherein, for each rail, a step is formed between respective upper ends of the inner and outer ramps, the step limiting axial movement of the pair of opposed resilient latch arms within the handle base when an axial pulling force is applied to the handle.

9. The detachable pick mechanism of claim 8, wherein the first acute angle is less than the second acute angle.

10. The detachable pick mechanism of claim 6, wherein, with the pair of opposed resilient latch arms being in an undeflected position, the respective catches extend through respective dwell gaps into the opening in the handle base.

11. The detachable pick mechanism of claim 10, wherein the catches are separated by a distance that is less than or equal to a distance of an inner diameter of the groove.

12. The detachable pick mechanism of claim 6, wherein during installation of the handle into the handle base, the catches initially engage respective outer ramps of the at least two opposed rails and the pair of opposed resilient latch arms are increasingly separated as they travel therealong, and, as installation of the handle continues, the catches transfer to the respective inner ramps of the at least two opposed rails with the pair of opposed resilient latch arms being decreasingly separated until the catches enter the respective dwell gaps and the pair of opposed resilient latch arms return to a substantially undeflected position.

13. The detachable pick mechanism of claim 6, wherein an aligned end of each catch has an axial notch therein forming a pair of opposed notches aligned with the respective first ends of the at least two opposed rails.

14. The detachable pick mechanism of claim 6, wherein, the at least two opposed rails further comprise two pairs of opposed rails with each end of each catch having an axial notch therein forming two pairs of opposed notches between the respective catches with one pair of opposed rails axially aligned with a corresponding pair of opposed notches in the catches.

15. A latch assembly comprising:

a post having a first end mountable to a first member in a cantilever manner, the post having a free end having a circumferential groove inboard thereof;

a handle base mountable to a second member, the second member and handle base each having respective aligned openings for receiving the free end of the post therethrough, the handle base including;

a pair of opposed guide arms; and

a pair of opposed resilient latch arms, the pairs of opposed resilient latch arms and guide arms depending from a same side of the handle base and being axially aligned with the opening in the handle base with each latch arm having a catch at a free end thereof; and

,

a handle slidably coupleable to the handle base and axially movable within the handle base, the handle including;

a support body having a first end and a second end, the support body having an axial opening extending between the first and second ends and a pair of opposed channels axially extending along an outer surface of the support body from the first end and aligned with the pair of opposed guide arms and sized for receiving therein a corresponding guide arm;

a grip axially depending from a second end of the support body having an opening therein aligned with the opening in the handle base and sized for receiving the free end of the post;

an end wall radially extending from the support body and positioned adjacent to the second end thereof;

at least two opposed rails axially positioned between the first and second ends of the support body, each rail having;

a first and a second end and extending along the outer surface of the support body from the first end of the support body toward the second end of the support body, the second ends of the at least two opposed rails being spaced apart from the end wall forming a respective dwell gap therebetween sized to receive therethrough the respective catches of the pair of opposed resilient latch arms;

an inner ramp having a bottom beginning adjacent to the second end of the rail and raising at a predetermined first acute angle; and

an outer ramp having a bottom beginning adjacent to the first end of the rail and raising at a predetermined second acute angle, the first and second catches moveable along respective outer and inner ramps,

wherein, with the post mounted in the first member, the handle base mounted on the second member and the handle installed in the handle base, during mounting of the second member onto the post using an axial pushing force applied to the handle, the end of the post initially separates the catches and deflects the pair of opposed resilient latch arms with the catches subsequently engaging the groove on the post and the pair of opposed resilient latch arms returning to a less deflected position thereby latching the second member to the post, and, during dismounting the second member from the post using an axial pulling force applied to the handle, the catches slide up the inner ramps of the at least two opposed rails and disengage from the groove in the post separating the catches a distance sufficient to allow the second member to slide off of the free end of the post.

16. The latch assembly of claim 15, wherein for each rail a step is formed between respective upper ends of the inner and outer ramps, the step limiting axial movement of the pair of opposed resilient latch arms within the handle base when an axial pulling force is applied to the handle.

17. The latch assembly of claim 16, wherein the first acute angle is less than the second acute angle.

18. The latch assembly of claim 15, wherein, with the pair of opposed resilient latch arms being in an undeflected position, the respective catches extend through respective dwell gaps into the opening in the handle base.

19. The latch assembly of claim 18, wherein the catches are separated by a distance that is less than or equal to a distance of an inner diameter of the groove.

20. The latch assembly of claim 15, wherein, during installation of the handle into the handle base, the catches initially engage respective outer ramps of the at least two opposed rails and the pair of opposed resilient latch arms are increasingly separated as they travel therealong, and, as installation of the handle continues, the catches transfer to the respective inner ramps of the at least two opposed rail with the pair of opposed resilient latch arms being decreasing separated until the respective catches enter the respective dwell gaps and the pair of opposed resilient latch arms return to a substantially undeflected position.

21. The latch assembly of claim 15, wherein an aligned end of each catch has an axial notch therein forming a pair of opposed notches aligned with the respective first ends of the at least two opposed rails.

22. The latch assembly of claim 15, wherein the at least two opposed rails further comprise two pairs of opposed rails with each end of each catch having an axial notch therein forming two pairs of opposed notches between the respective catches with one pair of opposed rails axially aligned with a corresponding pair of opposed notches in the catches.

23. The latch assembly of claim 15, wherein the free end of the post is a semi-hemispherical camming surface.

24. The latch assembly of claim 15, wherein the free end of the post is a polygonal planar camming surface.