首页
产品
黄页
商标
征信
会员服务
注册
登录
全部
|
企业名
|
法人/股东/高管
|
品牌/产品
|
地址
|
经营范围
发明名称
Sound reproducing device
摘要
申请公布号
US1907723(A)
申请公布日期
1933.05.09
申请号
US19290395802
申请日期
1929.09.28
申请人
BELL TELEPHONE LABORATORIES, INCORPORATED
发明人
BOSTWICK LEE G.
分类号
H04R1/24
主分类号
H04R1/24
代理机构
代理人
主权项
地址
您可能感兴趣的专利
Apparatus for making tubing continuously by electrodeposition
Heat recovery and temperature control system for bed of high temperature fluidized solids
Apparatus for stretching webs
Rectifier cell mounting
Magnetometer probe
Protective circuit
High-speed tandem arc working
Relay with time delay action
Snap-action device
Radio cover switch
Reforming cycle gas by thermocompressor
Individual freezing of eggs
Reduction of dye stain in processed photographic papers containing dyes
Adjustable work stop for lathe spindles
Method and apparatus for projecting pipes through ground
Shock isolator
Package collector for coin package machine
Apparatus for checking and replacing oil in engine sumps
Pistol grip tape applicator
Anti-tampering device for bottles
